Injury to the densely compacted structures of the hand often

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1 Principles of Metacarpal and Phalangeal Fracture Management: A Review of Rehabilitation Concepts Maureen A. Hardy, PT, MS, CHT 1 Journal of Orthopaedic & Sports Physical Therapy Patients with common hand fractures are likely to present in a wide variety of outpatient orthopedic practices. Successful rehabilitation of hand fractures addresses the need to (1) maintain fracture stability for bone healing, (2) introduce soft tissue mobilization for soft tissue integrity, and (3) remodel any restrictive scar from injury or surgery. It is important to recognize the intimate relationship of these 3 tissues (bone, soft tissue, and scar) when treating hand fractures. Fracture terminology precisely defines fracture type, location, and management strategy for hand fractures. These terms are reviewed, with emphasis on their operational definitions, as they relate to the course of therapy. The progression of motion protocols is dependent on the type of fracture healing, either primary or secondary, which in turn is determined by the method of fracture fixation. Current closed- and open-fixation methods for metacarpal and phalangeal fractures are addressed for each fracture location. The potential soft tissue problems that are often associated with each type of fracture are explained, with preventative methods of splinting and treatment. A comprehensive literature review is provided to compare evidence for practice in managing the variety of fracture patterns associated with metacarpal and phalangeal fractures, following closedand open-fixation techniques. Emphasis is placed on initial hand positioning to protect the fracture reduction, exercise to maintain or regain joint range of motion, and specific tendon-gliding exercises to prevent restrictive adhesions, all of which are necessary to assure return of function post fracture. J Orthop Sports Phys Ther 2004;34: Key Words: bone healing, hand, fingers Injury to the densely compacted structures of the hand often involves damage to multiple tissues. In this confined area, all neighboring tissues share trauma and its consequence. It is a mistake to consider fracture healing apart from soft tissue healing, because successful outcomes require the return of functional integrity to both tissues. Soft tissues commonly involved with fractures include cartilage (with intra-articular fractures), joint capsule, ligaments, fascia, and the enveloping dorsal hood fibers. Occasionally, in severe polytrauma cases, tendons and nerves adjacent to the fracture are also injured. Following open fractures or open reduction procedures, a wound is created that must heal with scar tissue another tissue to be remodeled and considered during rehabilitation. It is well recognized that soft tissue scarring affects hand function more than fracture healing, and joint stiffness is the most frequent complication of fractures Director, Hand Management Center, St Dominic Jackson Memorial Hospital, Jackson, MS; Clinical Assistant Professor, School of Health Related Professions, University of Mississippi Medical Center, Jackson, MS. Address correspondence to Maureen A. Hardy, Hand Management Center, St Dominic Jackson Memorial Hospital, 969 Lakeland Dr, Jackson, MS mhardy@stdom.com The optimal therapy program addresses these 3 components (bone, soft tissue, and scar healing) in combination. In the 1970s, therapy for hand fractures was delayed 6 to 8 weeks while the hand was immobilized. Stiff joints, adherent tendons, muscle atrophy, scar, and pain were the focus of our interventions. Results of corrective surgical procedures, such as capsulectomies for joint release and tenolysis to restore tendon gliding, were poor for patients with fractures. 16,43,101,113 Joints with stiffness and abnormal articular surfaces, due to limited reduction techniques in small bones, faced the choice of fusion (arthrodesis) or joint replacement (arthroplasty). Recent studies on fractures requiring combined capsulectomy and tenolysis show that outcomes are still poor, especially for return of active tendon function. 25,64,74,86 Add to this dilemma that 24% of digits that require these release procedures are noninjured, border digits that were included in the immobilization, and we lament along with Lanz, 64 who states that Damage of the gliding ability of tissues (around a fractured digit) is almost irreparable. Enhanced understanding of the biology of fracture healing, better decision making in initial fracture management, technical advances in implant design, improved surgical Journal of Orthopaedic & Sports Physical Therapy 781

2 skills with respect for gliding structures, and early controlled mobilization have contributed to reducing the incidence of complications that we once faced. The purpose of this manuscript is to review current concepts of management for metacarpal and phalangeal fractures, with special emphasis on potential problems that need to be addressed in the course of rehabilitation. The challenge for the health care team is to design intervention protocols that recognize the need to maintain fracture stability for maximal bone healing, while also introducing early, controlled-motion protocols to preserve soft tissue integrity and facilitate scar remodeling. This paper is based on a thorough review of the literature and current practice principles. The information is presented within the context of an overview of fracture healing, followed by guidelines for managing specific types of fractures common in the hand. PRINCIPLES FOR FRACTURE MANAGEMENT Is the Fracture Stable? The quest in fracture management is to achieve fracture stability. Fractures that are stable will heal; fractures that are not stable can result in malunions, infections, pseudoarthrosis, or nonunion. Stability of a fracture is achieved when the fracture maintains its reduction and does not displace either spontaneously or with motion. 39 If the fracture has not distorted the bone s normal contour and the fracture ends are approximated, it is termed nondisplaced. A bone that has lost its normal anatomical contour due to separation of the fracture ends is called displaced. The displaced fracture ends must be reunited for healing to occur and to prevent deformities. The methods used to bring anatomic order and realignment back to the fractured bone is called reduction. Reduction can be achieved by either closed manual techniques, by percutaneous fixation, or by open surgical methods. Stable fractures will maintain their position at rest and will not lose the proper approximation of fracture ends with inherent muscle tension or when controlled-motion protocols are initiated. Some fracture types are known to have intrinsic stability, such as nondisplaced transverse, and short oblique configurations. These fractures require no further intervention other than protective immobilization to allow healing to commence. Intrinsically stable fractures are usually treated with conservative, closed methods of support for 2 to 3 weeks, then supported with removable splints for initiation of controlled motion. Fractures that are aligned but subject to misalignment with certain postures or tensions are termed potentially unstable. Potentially unstable fractures include oblique, avulsion, and comminuted fractures. These fractures can often be managed with protective immobilization that maintains the reduction or restricts motion in the direction of instability. As fracture coalescence occurs, the immobilization can be modified to allow incremental increases in range of motion (ROM). Alternately, potentially unstable fractures can be supported with the introduction of coaptive hardware such as K-wires, pins, or wiring techniques that protect against displacement. These devices can be inserted either percutaneously (closed reduction) or via surgical exposure (open reduction). Coaptive forms of hardware bring about alignment, but they do not control for rotation stresses, nor do they impart any internal strength to the fracture. Coaptive devices therefore require further external support to eliminate unwanted deforming stresses as the fracture heals. Unstable fractures will not maintain reduction, as displacement reoccurs despite immobilization. Examples of unstable fractures include long oblique, spiral, condylar and any irreducible fractures, and fractures with articular fragments greater than 30% or incongruity greater than 2 mm. 39 Stability of these fractures can only be assured with the support provided by fixation devices. All fixation implants promote reduction, but some provide added internal strength across the fracture line. The more rigid implants, such as screws, plates, dorsal band, and wiring techniques, permit immediate motion and only require modest external support for wound care. The coaptive implants, however, such as pins, K-wires, intramedullary rods, staples, and interosseous wiring, do require more rigid external support as previously noted. 4,65 Is the Fracture Healing? Primary Bone Healing Implant choice drives the course of fracture healing. Implants introduced via open reduction internal fixation (ORIF) that provide absolute stability and compression of the fracture permit primary bone healing to occur. Primary bone healing is direct bone-to-bone healing without any external callus. Compression across the fracture line eliminates the space-occupying hematoma, thus reducing the fracture gap. Compression combined with rigid fixation, that eliminates all but micromotion, provides an environment suitable for osteoclast cutting cones to form and cross the fracture line. These cutting cones have osteoclasts that forage forward, by osteoblastic action, leaving an empty trail behind (haversian canal) that is filled with osteons (a single basic unit of bone). 75 For an in-depth review of fracture healing see LaStayo et al. 64 One advantage of primary healing via rigid internal fixation is precise anatomic reduction. This is especially important in articular fractures where joint incongruities can lead to degenerative joint problems. As the need for peripheral callus to support the bone ends is avoided (the metallic implant substitutes 782 J Orthop Sports Phys Ther Volume 34 Number 12 December 2004

3 for the callus), so also is avoided the potential problem of tissue adherence to the callus during immobilization. Once the surgical dressing is removed, usually in 3 to 5 days, there is full access to the hand for wound or edema control measures. Early initiation of motion is permitted as these implants provide sufficient internal support to allow motion without endangering the fracture alignment. 65 In polytrauma cases, soft tissue mobilization programs for repaired tendons can begin immediately without fear of displacing the fracture. A disadvantage of primary healing is that it can only occur with mechanical stabilization provided via surgery; consequently, there are 2 wounds to heal: the fracture and the soft tissue incision. Without the initiation of early motion post-orif, there is a greater potential for soft tissue adherence. Although new bone is formed more quickly in primary healing, it is not strong bone. 75 This newly formed woven bone (weak) will gain tensile strength as it is remodeled based on its environmental stresses and strains to become lamellar bone (strong). Bones healing by closed conservative management and those treated by open reduction methods achieve the same level of tensile strength by 12 weeks. This implies that primary healing is not faster healing, so strengthening programs must be delayed until the remodeling phase has begun at 6 to 8 weeks. Secondary Bone Healing Fractures treated by external support or coaptive implants, that reduce the fracture but do not provide compression, must rely on callus formation to bridge the fracture gap. Because bone formation will not occur in an environment of motion, callus is a temporary, biological fixation that forms in an area with motion and functions to reduce this motion as it matures and hardens (soft callus to hard callus). 7 Callus then resembles a natural glue that holds the fracture ends together. As the callus gains stiffness, the fracture fragments are rendered more stable. 42 Excessive, unrestricted motion can overwhelm the fragile support offered by early soft callus, leading to loss of reduction and possibly nonunion. 104 With secondary healing, ROM exercises are delayed or limited during the first 3 weeks, or until the callus has achieved enough tensile strength to tolerate controlled movement. Callus that is sufficiently clinically stiff at 3 weeks to permit motion is not strong enough yet to bear functional loads. 53 After 3 weeks, soft callus transitions into a harder fibrocartilage callus, then through a process of mineralization true bone is formed. Goodship 42 summarized this cascade of connective tissue differentiation as one in which, The entire spectrum of connective tissue is seen from blood to bone through hematoma, granulation tissue, fibrous tissue, fibrocartilage, hyaline cartilage, woven and ultimately lamellary bone. The primary advantage of secondary bone healing is that there is minimal soft tissue disruption. This equates to less scar remodeling. The periosteal sleeve, when intact, envelops the bone adding another internal layer of fracture support and is an important blood supply source for the bone. Noninvasive fracture management does not violate this tissue, as do open fixation methods that may require periosteal stripping for implant application. One disadvantage of secondary healing is the relatively long period of protected immobilization that is required, during which soft tissues can become contracted or adherent to the callus. Often, initiation of motion at 3 to 4 weeks is still limited to a safe range dictated by the fracture s potential instability. Prolonged immobilization results in atrophy of soft tissues, osteoporosis, thinning of articular cartilage, severe joint stiffness, and at times pain. 52 Is Closed or Open Reduction Required? The vast majority of metacarpal and phalangeal fractures can be treated without surgery, using closed methods that emphasize alignment and early protected motion (Figure 1). 69 Fracture immobilization should provide for adequate healing, relief of pain, protection from displacement or reinjury, and restoration of hand function. 45 All splinting programs recognize the need to position the metacarpophalangeal (MP) joints in flexion to avoid extension contracture. The thumb MP joint is not exempt from this rule and many stiff thumbs result from hyperextended thumb spica immobilization. The interphalangeal (IP) joints are routinely rested in full extension, with the exception of volar plate fractures. Unpublished data by Greer 45 states that the following principles (REDUCE) for effective plaster cast or thermoplastic splinting should be incorporated in all designs: (1) reduction of the fracture is maintained, (2) eliminate contractures through positioning, (3) don t immobilize fractures more than 3 weeks, (4) uninvolved joints should not be splinted in stable fractures, (5) creases of the skin should not be obstructed by the splint, and (6) early active tendon gliding is encouraged. Fractures that cannot be reduced with closed manipulation (or those that fail to maintain their reduction), open fractures, and displaced articular fractures are candidates for operative fixation procedures. Insertion of the fixation device does not always require a surgical incision. Closed reduction with external fixation or closed reduction with internal fixation includes percutaneous application of pins, K-wires, and external fixators under radiologic C-arm guidance. Limited open reduction and internal fixation uses small incisions to insert screws or intermedullary fixation. Open methods of internal fixation (ORIF) do require surgical exposure of the fracture for insertion of K-wires, plates, screws, and J Orthop Sports Phys Ther Volume 34 Number 12 December

4 FIGURE 1. Fracture stability achieved with closed reduction methods (cast, splint, brace, external fixator) or with coaptive forms of fixation (pins, K-wires, intramedullary rods) require a form of external support to promote callus formation during the inflammatory and repair stages of healing. As healing progresses, therapy intervention proceeds from edema prevention, to protected mobilization with tendon gliding of nonimmobilized joints, and to acceleration of controlled soft tissue mobilization for full active tendon gliding. Passive range of motion to regain full joint mobility, and strengthening programs, are delayed to the early and late remodeling phase, respectively, when the hard callus is converting to bone. Fracture stability achieved with open reduction methods (screws, wiring, plates) still require protective, postoperative splint support initially; however, full active motion can and should be emphasized early. Because the implant serves as a substitute for hard callus, passive motion can be initiated during the repair phase. Strengthening programs are delayed until the remodeling phase to assure fracture union, under the implant, has occurred. Reprinted from LaStayo 64 with permission from Elsevier. osseous wiring. The hardware used in fracture fixation falls into 2 categories: (1) coaptive devices that hold the fracture ends together without compression (secondary callus healing); and (2) rigid forms of fixation that immobilize and compress the fracture (primary healing). Freeland 39 stated that,...the choice of the implant is less important than achieving a threshold of stabilization that will allow fracture healing in concert with early rehabilitation. Coaptive Fixation: External Fixators, Intramedullary Rods, K-wires, Pins, Interosseous Wiring Jabaley 57 stated that fixation must be good enough to permit movement, but need not be excessive, given that the small bones in the hand do not bear weight. It is cautioned that well-placed coaptive implants that allow ROM exercises without load may be insufficient to protect the fracture against resistance (motion with load). One week after surgery a removable splint is applied in a functional, rehabilitation ready position, which the patient removes for suture/pin site cleaning, and to perform protected active ROM (AROM) exercises. 39 Full motion may not be possible at all joints due to constraints from the hardware. Controversy does exist regarding the initiation of motion with coaptive fixation. Incidence of infection, fracture displacement, nonunion, and pain have been cited as reasons to delay motion until the fixators are removed. 9,54 Advances in osteosynthesis materials is believed to provide sufficient stability to permit controlled, protected ROM exercises with this type of fixation in place. 8,32,44,78 Weiss 109 investigated initiation of motion at 1, 2, 3, and 4 weeks for individuals with proximal phalanx (P1) fractures with K-wire fixation. Results showed no difference in ROM when motion was initiated between 1 to 21 days. However, when motion was delayed more than 21 days, there was a significant loss of mobility. At 4 to 6 weeks, the K-wires and pins are removed, the splint is adjusted for proper fit and worn for continued fracture protection for another 2 weeks. AROM exercises (out of the splint) are performed hourly to regain full mobility. The callus is considered clinically stiff enough for free active motion but is not stable enough to bear a functional load, which occurs after 6 to 8 weeks. 53 Dynamic or serial static splints may be initiated after 6 to 8 weeks time to overcome any soft tissue contractures. Early strengthening exercises with light resistance can be initiated at 8 weeks, but unrestricted return to sports and heavy work is delayed until after 10 weeks, as callus remodeling to lamellar bone with increased fracture strength does not occur until this later stage of bone healing. 21 Rigid Fixation: Plates, Screws, Tension Band Wiring, Wiring Open reduction with rigid forms of fixation provide definitive fixation, assure compression for stability, and permit early motion for good restoration of function. 69 Full AROM is the early goal as edema diminishes. Dynamic splints may be used at 2 weeks for soft tissue stretching, because of the stability provided by the rigid fixation. An exception is forced extension with tension band wiring techniques, because the dorsal surface wiring on the metacarpal compresses the fracture with flexion but will cause gapping of the fracture with forced extension. Early strengthening exercises with light resistance can be initiated at 6 weeks, but unrestricted return to sports and heavy work is delayed until after 10 weeks, similar to secondary healing, to assure adequate fracture strength has occurred. It is important that therapists managing hand fractures understand the role and intent of the 784 J Orthop Sports Phys Ther Volume 34 Number 12 December 2004

5 various forms of fixation of fractures as they dictate the course of rehabilitation. Ideally the therapist would have access to both the radiographs and an operative/emergency department report on the medical management of the fracture. In the absence of this ideal environment, a minimum of 2 facts must be provided with the therapy referral: date of fracture and method of fixation. The fracture date starts the bone-healing timetable, and the method of fixation (dictating the type of healing) influences the rate at which motion can be reintroduced. The goals of hand therapy then are to reintroduce safe early mobilization while maintaining fracture stability. 91 Is the Edema Under Control? Edema after injury is common to all fractures. Patient education for edema control is an essential component of the initial therapy visit. Rest, ice, compression, and elevation ( RICE ) are emphasized for edema control. Edema is poorly tolerated in the digits due to the confining space. Distended joints predictably move into positions that permit the greatest expansion of the joint capsule and collateral ligaments. 35 Edema postures the hand into wrist flexion, MP joint extension, IP joint flexion, and thumb adduction: a dropped claw hand. Functional splinting seeks to place the hand in a resting position that will avoid this deformed posturing. Ice can be easily performed with the use of large bags of frozen peas (1 bag applied volarly and 1 dorsally) and is effective even over a splint or cast. Coban (sized 1 inch [2.5 cm] for fingers and 2 inches [5 cm] for the hand) is an elastic self-adhering bandage that provides effective compression. Eccles 33 showed that the greatest reduction in swelling was obtained with the hand supported in elevation overnight. Early mobilization to promote venous return via muscle contraction is advocated in stable fractures. Having the patient adduct the fingers tightly and maintain this tension while flexing at the MP joint can enhance both intrinsic muscle pumping and achieve the desired joint positions of full MP flexion and IP extension. Double buddy straps, applied proximal and distal to the proximal IP joint (PIP), serve to protect fracture alignment and encourage mobility of the injured digit. Patients are also instructed in shoulder and elbow ROM exercise in elevation to facilitate proximal muscle pumping. Are the Tendons Gliding? digitorum communis and central slip to prevent tendon adherence to fracture callus. 15 To assure the extensor tendon glide over fractured metacarpal bones, MP extension is performed in the hook fist posture (Figure 2A). To gain extensor hood glide over proximal phalanx (P1) fractures, the intrinsic plus position is performed, facilitated by manually blocking the MP joint into flexion (Figure 2B). Micks 71 showed that the central slip is responsible for initiating extension from a fully flexed PIP joint position, while the lateral bands (interossei and lumbricals) achieve full terminal PIP extension. If full PIP extension is lacking, flexing the wrist may assist by the addition of passive tenodesis action (stretch of the extensor mechanism). Selective gliding of flexor tendons is achieved by choosing positions that differentiate movement between the FDP and FDS to achieve maximal glide of each. Wehbe 106,107 used metal tags on the tendons to demonstrate that the FDP must glide 60 mm, compared to 49 mm of FDS glide, to achieve full fisting. This research suggests that for P1 and middle phalanx (P2) fractures, flexor tendons need to achieve maximal differential glide to prevent restrictive adhesions with loss of motion. FDP tendon gliding is performed by manually blocking the PIP joint to allow full flexor power to be directed to the distal joint (Figure 2C). To promote selective FDP flexor tendon glide past the superficialis tendon, the claw fist posture of MP extension with PIP and distal interphalangeal joint (DIP) maximal flexion is achieved (Figure 2D). FDS tendon blocking exercise requires inhibition of the FDP tendon of the same finger, which also contributes to PIP joint flexion. This inhibition of the profundus is achieved by manually restricting DIP motion in the unaffected digits with attempted PIP flexion in the involved digit (Figure 2E). Because the FDP tendons blend into 1 multistrand tendon inserting into the muscle belly, blocking 1 tendon s excursion effectively blocks all others. 14 The only motor that is now free to glide and flex the PIP joint is the FDS tendon. The sublimis fist (Figure 2F) maximally glides the FDS tendon past the FDP tendon with full MP and PIP flexion and an extended DIP joint. Full fisting, flexion of all 3 joints simultaneously, promotes full gliding of all flexor tendons with the FDP tendon gliding past the FDS tendon. 105 PRINCIPLES FOR MANAGING METACARPAL FRACTURES AROM is initiated as soon as possible, based on the method of fixation, to prevent osseous adhesions to tendons, ligaments, capsules, or skin. 82 The most important tendon-gliding exercises to initiate early are those for the flexor digitorum profundus (FDP), flexor digitorum superficialis (FDS), extensor The metacarpal bones have intrinsic stability provided proximally by strong interosseous ligaments binding them to the carpal bones, and distally by the transverse metacarpal ligament linking all metacarpal heads. These ligaments serve to tether and anchor both ends of the metacarpal, preventing excessive J Orthop Sports Phys Ther Volume 34 Number 12 December

6 A B C D Journal of Orthopaedic & Sports Physical Therapy E F FIGURE 2. Tendon glide exercises: (A) claw posture to achieve extensor digitorum communis (EDC) tendon glide over metacarpal bone; (B) intrinsic plus posture to achieve central slip/lateral bands glide over proximal phalanx (P1); (C) flexor digitorum profundus (FDP) blocking exercises to glide FDP tendon over P1; (D) hook fist posture to promote selective FDP tendon glide; (E) flexor digitorum sublimis (FDS) blocking exercise to glide FDS tendon over middle phalanx; (F) sublimis fist posture to promote selective FDS tendon glide. 786 J Orthop Sports Phys Ther Volume 34 Number 12 December 2004

7 displacement with injury. This is especially true for middle and ring metacarpal fractures as they have the additional support of intact adjacent metacarpals. Fractures in the border digits, index and small, tend to be more unstable due to loss of surrounding intact metacarpal pillars. The thumb metacarpal, sitting at 47 rotation away from the other digits, is the most mobile and most unstable if fractured. 100 Metacarpal fractures represent 35% of hand fractures. Due to their good blood supply, these fractures heal rapidly with osseous restoration in 6 weeks. Fractures of this bone are described at 4 distinct locations: base, shaft, neck, and head. The most important soft tissue concerns with metacarpal fractures are preserving MP joint flexion and maintaining EDC glide. Table 1 lists the potential problems that can occur and strategies for therapeutic intervention. Metacarpal Base Fracture Base fractures are an intra-articular fracture resulting from high force that disrupts the rigid carpal ligaments (index and middle), or overwhelms the normal flexibility of the ulnar metacarpals (ring and small). 41 The insertions of the wrist flexors and extensors on the metacarpal base can be a deforming force. These are uncommon injuries associated with violent accidents resulting in a fracture-dislocation pattern. The most common occurrence is at the fifth metacarpal-hamate articulation, which is often unstable due to the pull of the extensor carpi ulnaris, flexor carpi ulnaris, and abductor digiti minimi that insert on the metacarpal base. 12 Fractures at this location limit the normal descent of the ulnar metacarpals, causing weakness of grip. The deep motor branch of the ulnar nerve, passing beneath the hook of the hamate, is also vulnerable to injury in this fracture. 76 The index and middle metacarpal base fractures are also unstable due to the insertion of the extensor carpi radialis longus and flexor carpi radialis on the second metacarpal and extensor carpi radialis brevis on the third. Closed reduction with casting of the wrist for 4 to 6 weeks is indicated for nondisplaced or minimally displaced fractures. Bora 12 reported satisfactory return of grip strength and activities in 18 patients treated with this method. Displaced fractures represent an associated carpometacarpal joint dislocation that can lead to joint incongruity, degenerative joint disease and ultimately further carpal collapse. 41 ORIF is necessary to restore joint approximation, prevent pain, and assure return of grip strength. Postoperatively, a cast is worn for 4 to 6 weeks to protect this injury at the wrist. This prolonged immobilization is necessary to protect the healing fracture from the deforming forces of the wrist tendon insertions. 70 During this time the fingers are free and encouraged to move. Once clinical signs of healing are present, a protective wrist splint is used for 3 to 4 weeks while wrist rehabilitation is initiated. TABLE 1. Potential problems with metacarpal fractures and strategies for therapeutic intervention. Potential Problems Dorsal hand edema Dorsal skin scar contracture that prevents full fist MP joint contracted in extension Adherence of EDC tendon to fracture with limited MP joint flexion Intrinsic muscle contracture secondary to swelling and immobilization Dorsal sensory radial/ulnar nerve irritation Attrition and potential rupture of extensor tendon over prominent dorsal boss or large plate Scissoring/overlapping of digits with flexion Absence of MP head Absence of MP head and MP joint extension lag Absence of MP head with volar prominence and pain with grip Prevention and Treatment Coban wrap compression, ice, elevation, high-voltage stimulation Silicone TopiGel, simultaneous heat and stretch with hand wrapped in a fisted position; friction massage Initially: position MP joint at 70 flexion in protective splint Late: dynamic or static progressive MP joint flexion splint Initially: teach EDC glide exercises to prevent adherence; splint IP joint in extension during exercise to concentrate flexion power at MP joint Late: dynamic MP flexion splint; NMES of EDC with on off cycle Initially: teach instrinsic stretch (instrinsic minus position) Late: static progressive splint in intrinsic minus position Desensitization program; iontophoresis with lidocaine Rest involved tendon; contact physician if painful symptoms with AROM persist Slight: buddy tape to adjacent digit Severe: malrotation deformity requiring ORIF Shortening of metacarpal; may not be functional problem Shortening of metacarpal with redundancy in extensor length; splint in extension at night; strengthen intrinsics abduction/adduction; NMES of intrinsics with off on cycle Neck fracture angulated volarly; minor: padded work glove; major: reduction of angulation required Abbreviations: AROM, active range of motion; EDC, extensor digitorum communis; MP, metacarpophalangeal; IP, interphalangeal; NMES, neuromuscular electrical stimulation. 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8 Metacarpal Shaft Fracture Shaft fractures are extra-articular fractures caused by fall, blow, or crushing force that usually angulate dorsally and may have components of shortening and/or rotation. They are described by the fracture configuration as transverse, oblique, or spiral. Intrinsic muscle tension, arising from its origin on the volar proximal metacarpal through its bony insertion on the proximal phalanx, will cause both ends of the metacarpal bone to flex towards each other, pushing the fracture ends dorsally (known as apex dorsal presentation). Resting tension of the long extrinsic finger flexors contributes to the deformity. Metacarpal fractures with apex dorsal angulation cause the metacarpal bone to be shortened, causing a deleterious effect on the extensor mechanism by altering the muscle s normal length-tension relationship. For each 2-mm increment of bone shortening there is a corresponding 7 extensor lag at the MP joint. 97 The natural ability to hyperextend the MP joint will overcome this extensor loss for minimal bone shortening; but this deformity leaves a prominent dorsal boss that has been implicated in attrition rupture of extensor tendons. 96 Stable, nondisplaced transverse metacarpal shaft fractures with apex dorsal angulation can be treated closed with glove support, 68 buddy taping, 112 short hand casts, 29 long ulnar/radial gutter splints, or hand-based fabricated splints that incorporate 3 points of reduction pressure (1 dorsal point over the fracture site and 2 volar points, proximal and distal to the fracture, that provide counterpressure). 70,102,103 C-arm visualization of the fracture with the splint on will assure improvement in the angulation after 1 week. 58 Sorenson 92 found poor compliance and skin breakdown with prefabricated splints as compared to ulnar gutter casts. Konradsen, 61 using fiberglass casting, and Jones, 58 using thermoplastic material, fabricated custom-made, hand-based fracture braces with the 3-point reduction technique. Both studies compared this functional brace, which allowed wrist and digital motion, with plaster ulnar gutter casting. Together, these 2 studies support the advantages of the functional brace with improved motion, decreased pain, ability to deliver corrective reduction force, less extensor lag, and decreased need for postfracture therapy. Current best-practice fracture support for managing nondisplaced, angulated metacarpal shaft fractures is provided by custommade casts or splints that incorporate the 3-point pressure fixation built within the splint and allows free active joint motion (Figure 3). Fractures that are potentially unstable require additional support. Ulnar or radial gutter splints that immobilize both the injured metacarpal and its adjacent stable metacarpal, including wrist, MP, and PIP joints have been the norm (Figure 4A-B). Feehan 36 A B FIGURE 3. (A) metacarpal shaft fracture treated with 3-point pressure fixation built inside splint; (B) straps secured to apply corrective pressure to dorsal apex angulation of fracture. proposed the concept of serial splint reduction, in which the splint is gradually cut down as fracture healing proceeds, permiting controlled-motion exercises (Figure 4C-D). Multiple metacarpal fractures may require that all fingers be included in the cast (Figure 5A). Ashkenaze 6 described a splint that includes the wrist and metacarpal shafts with dorsal support extending out to the PIP joint, with the volar support ending at the distal palmar crease to allow free MP and IP joint motion. Seventy degrees of MP joint flexion reduces the intrinsic and extrinsic flexors influence on dorsal angulation. 90 The IP joints are free to move during the day but strapped into extension at night to prevent flexion contractures (Figure 5B). Buddy strapping of the injured digit to a noninjured adjacent finger, especially in oblique fractures, is protective against malrotation and facilitates early motion. Hall 47 reported using this type of clam digger immobilization in over 1000 fractures, modified to plaster in noncompliant patients. This best-practice management technique assures protection of fracture stability, maintains proper hand posture, and respects the 788 J Orthop Sports Phys Ther Volume 34 Number 12 December 2004

9 A B Journal of Orthopaedic & Sports Physical Therapy C FIGURE 4. (A) Radial gutter splint for fractures of index or middle metacarpals; (B) ulnar gutter splint for fractures of ring or small metacarpals; (C) serial reduction of splint to permit motion as fracture healing occurs; (D) passive range of motion in splint. importance of motion in the early rehabilitation of fracture. Oblique and spiral metacarpal fractures can shorten and rotate. The ill effects of this telescoping and malrotation will be evident when the patient attempts to make a fist. The rotated position of the metacarpal will cause digital overlapping and the telescoping will cause loss of the normal metacarpal D head prominence of the involved bone. Following ORIF, a circumferential, hand-based splint is worn to protect the metacarpal area from direct trauma; no joint motion is restricted with this splint. Kuntscher 63 reported that 105 fractures postoperatively provided with this type of functional fracture brace resulted in decreasing the number of hand therapy visits with early, pain-free return of hand function. J Orthop Sports Phys Ther Volume 34 Number 12 December

10 A B FIGURE 5. (A) Cast for multiple metacarpal fractures permitting early active finger flexion; (B) resting volar component added to maintain interphalangeal joints in full extension. Metacarpal Neck Fracture Neck fractures are the most common metacarpal fracture, also known as fighter s or boxer s fracture. The impact of a closed fist hitting an object can fracture the metacarpal at its weakest point, the extra-articular neck. With fight/bite injury, the fist contact with the mouth of another can result in tooth penetration into the MP joint. Any skin laceration at the MP joint level with fight/bite fractures should be suspect for infection. Trauma causes the fractured metacarpal head to displace with volar angulation. Debate continues over the necessity to reduce and immobilize these fractures. 3,14,56 However, angulated neck fractures that heal with volar displacement over 30 place the intrinsic muscle in a shortened position, which reduces the muscle s excursion capacity. This loss of full muscle length results in limited ability to initiate flexion at the MP joint. 3 Other complications of poorly reduced neck fractures include a metacarpal head prominence in the palm that is painful with grip, and compensatory hyperextension of the proximal phalanx at the MP joint to clear the fingers for grasp. Acceptable angulation is less than 15 in the index and middle metacarpals, while the ring and small metacarpals can function with less than 30 due to their compensatory mobility. If these acceptable reduction angles cannot be maintained with external support alone, then operative treatment is recommended. 93 Once the volarly flexed metacarpal head is reduced back in proper alignment with the shaft, it is important to hold the MP joint in over 70 flexion, as the taught collateral ligaments will aid in securing the metacarpal head in place. A traditional clam digger or intrinsic plus splint can be used that includes: (1) keeping the wrist in slight extension; (2) holding the MP joint in flexion by a dorsal block component that extends out to the PIP joint; (3) stopping the volar side of the splint at the MP web area, permitting limited MP and full PIP flexion. 5,24 Neck fractures have also been treated with a hand-based splint that incorporates the 3 points of pressure and must extend volarly over the palmar aspect of the metacarpal head to apply the correct dorsal force. 48,61 Jones 58 instructed patients to gradually tighten the straps as edema subsided, and found that this gradual application of stress reduced the fracture as effectively as manipulation with anesthesia. It is recommended that reduced fractures use the hand-based splint that maintains the MP flexed with a dorsal block. 24 If reduction is inadequate or potentially unstable, the 3-point splint should be used. Closed reduction percutaneous pinning with K-wires is recommended to maintain reduction in unstable neck fractures. 88 One week postoperatively, the surgical dressing is removed and an immobilization splint is applied to protect this coaptive fixation at that time. The patient is instructed in protected ROM exercises out of the splint. At 4 to 6 weeks the K-wires are removed and the patient should then regain full AROM. Metacarpal Head Fracture Head fractures are intra-articular fractures caused by high axial loads that can involve avulsion of the collateral ligaments, including a fracture fragment, fracture of 1 or both condyles, or shattering of the joint surface into many small-comminuted pieces. Collateral ligament avulsion fractures if undetected can lead to chronic pain and joint instability. If the fracture fragment is nondisplaced, the injury can be treated with protective splints that hold the MP joint flexed at 50 to 70 for 4 to 6 weeks. 38 Displaced fractures require ORIF with fixation that allows early protected motion. 93 Fracture displacement of 1 to 2 mm at the articular surface is more easily tolerated in the upper extremity than in the lower extremity weight-bearing joints; however, ORIF is indicated for fractures that involve more than 20% of the articular surface to prevent erosive joint changes and to allow AROM by the third week postfracture. 6, J Orthop Sports Phys Ther Volume 34 Number 12 December 2004

11 Comminuted fractures that do not lend themselves well to operative fixation, due to the many small fragments involved, can be treated with closed immobilization in a radial/ulnar gutter splint with the MP joints flexed to 70. However, comminuted fractures with substantial loss of bone length are better treated with external fixators or bridging plates that maintain bone length. 23 Immobilization is shortened to 2 to 3 weeks, because early motion benefits articular cartilage repair. Salter 80 cautions that excellent reduction of the fracture may still lead to a poor result due to the concomitant cartilage injury with its limited regenerative capacity. His definitive work on intraarticular fractures showed that continuous passive motion begun in the first postoperative week stimulates both bone and cartilage healing. 81 PRINCIPLES FOR MANAGING PHALANGEAL FRACTURES Phalangeal fractures are more unstable than metacarpal fractures as they lack intrinsic muscle support and are adversely affected by tension in the long finger tendons. 112 Phalangeal fractures respond more unfavorably to immobilization than metacarpal fractures, with a predicted 84% return of motion, compared to 96% return in metacarpal fractures. 88 If immobilization is continued longer than 4 weeks, the motion return drops to 66%. 98 In 19% of digital fractures, nonfractured neighboring fingers also lose motion. 55 Functional outcome in these fractures is not so dependent on fracture site; rather, unsatisfactory results are more related to open fractures, comminuted fractures, and associated soft tissue injuries. 78 Table 2 lists potential problems that can occur with phalangeal fractures and strategies for therapeutic intervention. Proximal Phalanx (P1) Base Fracture Intra-articular base fractures are due to an abduction force from sports injuries or a fall on an outstretched hand. These articular fractures require accurate reduction to restore normal joint kinematics. After reduction, stability of the fracture position can be maintained with conservative treatment due to tension in the surrounding intact joint capsule, collateral ligament complex, interossei tendons, and volar plate for fractures in the proximal 6- to 9-mm range from the joint. 111 Positioning the MP joint in 70 flexion results in balanced tension of these capsular structures. The PIP and DIP joints, buddy taped to an adjacent digit, are allowed early active motion. The intrinsic plus position of the splint design also causes the extensor aponeurosis to be tightened and drawn distally over the base of P1, providing compression of the fracture. After 2 to 3 weeks, 79 or 3 to 4 weeks, 32 depending on callus formation, the splint can be removed for protected ROM at the MP joint. TABLE 2. Potential problems with phalangeal fractures and strategies for therapeutic intervention. Potential Problems Loss of MP flexion Loss of PIP extension Loss of PIP flexion Loss of DIP extension Loss of DIP flexion Lateral instability any joint Impending Boutonniere deformity Impending swan neck deformity Pseudo claw deformity Pain Prevention and Treatment Circumferential PIP and DIP extension splint to concentrate flexor power at MP joint; NMES to interossei Central slip blocking exercises; during the day MP extension block splint to concentrate extensor power at PIP joint; at night PIP extension gutter splint; NMES to EDC and interossei with dual channel setup Isolated FDP tendon glide exercises; during the day MP flexion blocking splint to concentrate flexor power at PIP joint; at night flexion glove; NMES to FDS Resume night extension splinting; NMES to interossei Isolated FDP tendon glide exercises; PIP flexion blocking splint to concentrate flexor power at DIP joint; stretch ORL tightness; NMES to FDP Buddy strap or finger hinged splint that prevents lateral stress Early DIP active flexion to maintain length of lateral bands FDS tendon glide at PIP joint and terminal extensor tendon glide at the DIP joint Splint to hold MP joint in flexion with PIP joint full extensor glide Resume protective splinting until healing is ascertained; address edema, desensitization program Abbreviations: DIP, distal interphalangeal; EDC, extensor digitorum communis; FDP, flexor digitorum profundus; FDS, flexor digitorum superficialis; MP, metacarpophalangeal; NMES, neuromuscular electrical stimulation; ORL, oblique retinacular ligament; PIP, proximal interphalangeal. Displaced base fractures can not be reduced with MP joint positioning alone as often the collateral ligament, attached to the fracture fragment, is avulsed. Shewring s review 89 of 33 displaced base fractures found a high rate of nonunion with conservative management due to displacement of the fracture as the collateral ligament tightens with flexion of the MP joint. These avulsion fractures occur most often at the ulnar collateral ligament of the thumb or J Orthop Sports Phys Ther Volume 34 Number 12 December

12 A B FIGURE 6. (A) Wrist and distal joint immobilizer splint used during exercise sessions to promote flexion at the metacarpophalangeal joint (MP); (B) MP joint flexion isolated during exercise with use of dual blocking splints. index and radial collateral ligament of the ring and small fingers. 8,79 Techniques used for fixation of displaced fractures include tension band wiring using a figure-of-eight weave, 62 intraosseous wiring with additional K-wire support, 110 or screw fixation. 2,50 As MP joint stiffness with loss of flexion is the most common postoperative soft tissue complication of P1 base fractures, protective splinting must rest the MP joint in flexion. When active exercises are initiated to regain full MP flexion, the use of splints holding the wrist, PIP, and DIP joints immobilized during exercise, will facilitate all flexor strength directed towards the MP joint (Figure 6A-B). Continuous passive motion (CPM) following ORIF with rigid fixation is indicated to maintain joint mobility, decrease edema, and stimulate the healing of articular cartilage. 81 P1 Shaft Fracture Fractures occurring in digital flexor zone II, called no man s fractures, 17 are renown for the worst prognosis in regaining full mobility. 31 Ninety percent of the bone s surface is covered by gliding structures the central tendon dorsally, lateral bands bilaterally, and the FDP tendon volarly that can easily become adherent to fracture callus. Fractures of the shaft require accurate reduction to allow these soft tissues to glide normally. 110 Nondisplaced fractures require protection, but not total immobilization. Inclusion of a neighboring noninjured digit in the splint and buddy strapping permit early AROM. Oxford 73 recommends a singledigit circumferential splint for stable fractures, which provides extended lateral support at the PIP joint for distal shaft fractures or volar and dorsal immobilization of the MP joint for proximal shaft fractures. This design allows for free active PIP joint motion. Displaced P1 fractures present with apex palmar angulation. This angulation is due to a volar force at the base of P1 by the interossei insertion, while the extensor expansion pulls the distal fragment dorsally. 11 Freeland 39 recommends that the least intrusive technique be used to provide a threshold of strength that reliably holds the fracture securely...and would allow simultaneous early rehabilitation. Methods of fixation for displaced, unstable fractures include closed transcutaneous insertion of K-wires or intramedullary rods, percutaneous miniscrews, open internal fixation with miniscrews, miniplates, and mini external fixators. 40 The most common problem at this level begins with an extensor lag at the PIP joint, which develops into a fixed joint flexion contracture. 74 The worst case scenario results when minimal motion at the PIP joint results in a fixed flexed position of the joint, which is compensated at the MP joint with hyperextension to remove the flexed finger from the palm. A pseudo-claw hand posture is created. Prevention of this deformity relies on emphasizing PIP joint extension at rest and early tendon glide along all bone surfaces. Initially, a splint is made that maintains flexion at the MP joint, with a dorsal hood expansion to securely strap the PIP joint into full extension at rest (Figure 5). 24 The volar part of the splint stops at the distal palmar crease. Hourly the distal straps are removed to permit early tendon gliding, emphasizing central slip, lateral bands, FDS, and FDP tendons, respectively. Full PIP joint flexion is not promoted until the patient is able to actively extend the PIP joint to Burkhalter 17 reminds us that it is far easier to gain flexion than extension at this joint. Later, a functional blocking splint can be used to counter the pseudo-boutonniere posturing that occurs with less than optimal tendon gliding (Figure 7A-B). The splint immobilizes the MP joint in flexion, protecting against MP hyperextension, while also directing all flexor and extensor tendon power to the PIP joint. Light-resistance exercises for PIP joint flexion and PIP joint extension are facilitated when performed in the splint. P1 Condylar Fracture The 2 condyles at the head of the proximal phalanx, with their intimate convex-concave fit on the middle phalanx base, provide stability to a joint 792 J Orthop Sports Phys Ther Volume 34 Number 12 December 2004

13 A B FIGURE 7. (A) Pseudo-boutonniere deformity of ring digit following proximal phalanx fracture; (B) the blocking splint facilitates flexor and extensor tendon gliding at the proximal interphalangeal joint (PIP). deprived of much soft tissue support. The type of tissue injury caused with a lateral deviation force is dependent on the rate of loading: stress applied with low loading rate causes collateral ligament injury, while a high loading rate can result in a collateral avulsion fracture, or a unicondylar (1 side) or bicondylar (2 sides) fracture configuration at the head of P1. 60 A ball forcing the digit away from the center line of the hand most often fractures the condyle towards the middle of the hand. 109 Thisisa common sports injury that is often misdiagnosed as a jammed finger as the athlete can move the finger well. 82 Continued unsupported use of the hand can change a simple nondisplaced fracture into an angulated fracture with painful joint incongruity. 93 These potentially unstable fractures are best treated with ORIF to assure good joint alignment is achieved. The problem with ORIF at this level is access to the P1 head directly under the central extensor slip. Authors have advocated various incision locations: splitting the extensor tendon longitudinally, 77 incising between the lateral band and the central tendon, 72 excising the insertion of the central tendon creating a flap, 20 or a lateral midaxial incision. 54 As the most significant complication following P1 fracture is loss of full PIP joint extension, the lateral approaches that spare direct trauma to the central tendon are more appealing. However, Horton 48 found that despite the lateral incision used for screw placement, the ORIF group in his study had 3 times greater PIP joint extension lag (27 ), as compared to the group that received closed reduction treatment (8 ). This may be partly explained by the mutually dependent role played by the central slip and lateral bands in achieving full PIP joint extension. It may be that adhesions in either system will affect PIP joint extension. Pain and swelling at the PIP joint postoperatively are a great barrier to rehabilitation. Swelling will draw the joint into a flexed posture that over time will become a contracture. Splinting must rest the PIP joint in full extension, with hourly short-arc AROM performed. It is crucial that the patient work to achieve proximal gliding of the extensor mechanism, and thus 0 extension to prevent an extensor lag. The use of continuous passive motion (CPM) following rigid internal fixation of these fractures results in regeneration of hyaline articular cartilage, reduction of edema, prevention of adhesions and joint stiffness, and is painless. 80 Incised and repaired central slip tendons can also be treated with the short-arc-motion protocol, as there is continuity of the extensor tendon longitudinally. Full PIP joint flexion is limited for 3 weeks to prevent splitting the sutured tendon approximation. Middle Phalanx (P2) Base Fracture This intra-articular fracture is caused by a hyperextension, hyperflexion, or lateral deviation force on an outstretched finger, as occurs in basketball and volleyball injuries, or from a fall onto the outstretched hand. 87 Hyperextension or hyperflexion injuries are often severe enough to cause the PIP joint to dislocate with associated soft tissue damage to the volar plate or central slip respectively, commonly called avulsion fractures. With severe compressive trauma, comminuted fractures of the articular surface occur, causing depression of the fragments into the bone shaft, called a pilon fracture. Pilon is derived from the Latin word pounder, indicating the force required to create this deformity. 95 Palmar Plate Avulsion Fracture Also known as dorsal fracture dislocation, this fracture results from a hyperextension injury in which the distal attachment of the volar plate, at the base of P2, is ruptured along with a variable portion of the articular surface of the volar middle phalanx. Without the normal restrains provided by an intact volar plate, tension from the finger extensors on their distal attachment causes the base fracture to dislocate dorsally. The percent of articular surface involved and the percent of joint dislocation determine severity of this fracture. 83 Buddy taping and immediate active motion are used to manage less severe fractures. Fractures of moderate severity (20% to 40% of the articular surface involved) are treated with extension block splinting J Orthop Sports Phys Ther Volume 34 Number 12 December

14 for greater than 6 weeks. This fracture is at risk for displacement with full extension. A dorsal block splint prevents the joint from extending by 30 to 40, yet allows full joint flexion (Figure 8). This protocol allows fracture compression with flexion, while avoiding fracture separation with extension. As fracture healing ensues, the splint angle is subsequently remolded at less extension block weekly, permitting gain in extension range. Usually there is a slight flexion contracture at the end of the 6- to 8-week splinting regime, which can be treated with dynamic extension splinting. 30 Fractures with greater than 40% of joint surface involvement usually do not remain congruent in any limited arc of motion and are therefore managed with ORIF. Central Slip Avulsion Fracture This fracture, also known as dorsal fracture dislocation or boutonniere fracture, includes a fracture fragment from the dorsal base of P2 that is attached to the central extensor tendon. Fortunately it is a rare injury and treatment depends on the ability to restore the volar subluxed P2 back to approximate the avulsed fragment. Reduced fractures are immobilized in full PIP joint extension for 4 to 6 weeks, and the patient is instructed in active DIP joint flexion exercises to maintain gliding and length of the lateral bands and oblique retinacular ligament (Figure 9). Flexion at the DIP joint will prevent the appearance of a boutonniere deformity post immobilization. 22 Closed reduction, however, is often difficult due to soft tissue constraints, necessitating ORIF with pin, screw, or tension band wiring. 8 A removable protective fingerbased splint is worn that maintains the PIP joint in FIGURE 8. Volar plate avulsion fracture treated with extension block splint that limits full extension at the proximal interphalangeal joint (PIP); the degree of blocking is determined by fracture displacement with extension. The distal strap (not shown) is removed to allow active PIP and distal interphalangeal joint (DIP) flexion and extension. FIGURE 9. Cast for central slip avulsion fracture that maintains full proximal interphalangeal joint extension while allowing active distal interphalangeal joint flexion to maintain the length of oblique lateral ligaments and lateral bands. FIGURE 10. Dynamic traction splint for comminuted pilon fractures. The finger is moved passively along the arc several times per day to stimulate regeneration of articular cartilage and remodel the joint surface. Rubber band tension is measured to assure 300 g of ligamentotaxis distractive force throughout the range. full extension and is removed for passive ROM exercises. Pins are removed at 2 to 3 weeks, at which time, active ROM can begin to further glide soft tissues. With screw fixation, active motion can begin immediately with the use of the same splint to prevent flexed posturing at the PIP joint. Pilon Fracture Severe compressive trauma can cause the head of the proximal phalanx to impact into the base of P2, creating many small, crushed fracture fragments. The distal articular surface of the PIP joint is essentially destroyed. ORIF seeks to elevate the central depressed articular fragments and maintain their length with bone grafts or external fixators. 51 Another option is to use a combination of traction and motion to model a new joint through the use of dynamic traction splinting (Figure 10). This latter method uses a radial or ulnar gutter splint that blocks the MP joint in flexion. Rubber band 794 J Orthop Sports Phys Ther Volume 34 Number 12 December 2004

15 traction from a circular outrigger is attached to exposed K-wires passed through the middle phalanx distal to the fracture. Tension is measured with a Halston gauge to assure that adequate distractive force of 300 gm is exerted. The distractive force uses a concept called ligamentotaxis, in which the soft tissue envelope that encircles the fracture (intact periosteum, collateral ligaments, joint capsule) is placed under longitudinal tension, causing these soft tissues to narrow and compress the fracture. 58 During the day the dynamic-traction component is moved along the circular outrigger hoop to achieve passive PIP joint motion, which is beneficial to articular cartilage healing. The splint is worn continuously for 6 to 8 weeks (removed briefly for dressing purposes) to prevent displacement of the fracture. 46 Kearney 59 reported on a 9-year follow-up of patients treated with dynamic traction and found that all joints were pain-free and asymptomatic, they maintained their 87 arc of PIP joint motion, and the joint space had been maintained, indicating good cartilage thickness. The use of dynamic traction for pilon fractures was compared with ORIF and found to produce the same results with fewer complications. 95 P2 Shaft Fracture Fractures at this location are rare, due in part to the short, broad shaft that is stronger here than in proximal bones. The path of the lateral bands, spiraling from their lateral position at the PIP joint to become conjoined dorsally over the distal part of this phalanx, place them in jeopardy of adhering to fracture callus with closed methods, or of becoming impaled with pins and screws with open methods. Longitudinally placed pins down the medullary canal try to avoid this soft tissue problem. 8 Limitation of lateral band gliding will result in loss of DIP joint terminal extension. Midshaft fractures can angulate either dorsally or volarly, resulting in shortening of the middle phalanx shaft. This skeletal shortening will cause an imbalance in extensor tendon-bone length ratio, resulting in loss of terminal DIP joint extension. Loss of full DIP joint extension, due to either lateral band adherence or redundance, leads to the classic swan neck deformity of DIP flexion with excessive extensor force directed at hyperextending the PIP joint. 1 Cannon 19 recommended 3 weeks immobilization with closed methods or K-wire fixation, as FDS tendon action can displace this fracture due to its insertion on the P2 shaft. The digit is splinted in the functional position of MP joint flexion with PIP and DIP joints in full extension. For long oblique or spiral fractures, ORIF or percutaneous use of screws provides enough stability to allow AROM within 1 week. Emphasis is placed on FDS tendon glide at the PIP joint and terminal extension glide at the DIP joint, countering the swan neck deformity. P2 Neck Fracture Neck or subcapital fractures are more common in young children whose fingers have been trapped in closed doors or electric windows. These fractures are usually markedly displaced and unstable, requiring ORIF. Stern s review 93 of complications suggests that K-wires should remain in for a longer duration of 4 to 6 weeks. Postoperative therapy is based on the stability of the fixation. DIP joint stiffness, with loss of active flexion, and an extensor lag are the chief complications. Protective splinting of the DIP joint in full extension, with frequent removal for FDP tendon gliding is recommended. Distal Phalanx (P3) Fractures The distal exposed portion of the finger is most vulnerable to injury, with fractures at the P3 level accounting for 50% of hand fractures. 18 Causes of fracture include crush to the distal tuft, as when fingers are caught in closed doors or machines, blows to an extended finger, and sports-related volar and dorsal articular avulsion fractures. 84 P3 Base Fracture Articular avulsion fractures are closed injuries that result when an actively contracting tendon is forcefully pushed into the opposite direction. Tendon rupture alone can occur, or an articular fragment of variable size can be avulsed along with the tendon. Two common types of avulsion fractures at this level are jersey fracture and baseball fracture. Volar Jersey Avulsion Fracture This fracture is named after the football injury in which one player grabs the shirt of an opponent who pulls away forcefully, causing the FDP tendon, with a bone chip, to be avulsed from the volar base of P3. Loss of terminal joint active flexion requires early and judicious care, as FDP tendon muscle shortening can occur if undetected. With small fragments, the tendon (with the fracture fragment attached) is surgically reattached through P3 using wire pull-out sutures over a dorsal button. A dorsal blocking splint is fabricated and the postoperative Durand tendon motion protocol is followed. 19 Large fracture fragments require the additional support of K-wires to assure good joint surface congruence is achieved. 84 A modified Durand program is performed, omitting DIP joint flexion until the wire is removed. Dorsal Avulsion Fracture This fracture, known as mallet fracture or baseball fracture, is common to all sports and hobbies in which an extended finger is forced into either flexion or hyperextension. 65 The extensor terminal tendon is avulsed off the dorsal base of P3, with a chip of variable-sized bone attached. If the fracture piece represents less that one third of the articular surface, it may be managed with J Orthop Sports Phys Ther Volume 34 Number 12 December

16 FIGURE 11. Tip protector splint bivalved to maintain distal interphalangeal joint (DIP) extension and accommodate swelling for mallet fractures. closed splinting of the DIP joint in extension for 6 weeks (Figure 11). Bivalving the splint, which is secured with coban wrap, allows accommodation for any swelling. Splinting is continued at night and during vigorous activities for another 2 to 4 weeks. If extensor lag at the DIP joint is noted, then splinting is resumed during the day also. Fracture fragments that are greater than one third of the articular surface can be surgically reattached using various wiring techniques. 10,27,28,99,108 Damron s 27 analysis of these common fixation methods noted that none of the fixation methods provide enough stability to permit early motion. All joints must be immobilized for a minimum of 6 weeks, as with conservative methods. Surgical treatment for mallet fractures have been reported to have a 53% complication rate due to infection, joint incongruity, nail deformity, and extensor lag; as opposed to a 45% complication rate for closed treatment. 94 Wehbe 106 suggests that due to these findings most mallet fractures should be treated with conservative closed methods. Following the 6 weeks of continuous immobilization in extension, composite flexion and extension of the PIP and DIP joints is taught. Blocked DIP joint flexion exercises are not performed, as this would stretch out the oblique retinacular ligament (ORL). Because the greatest complication of mallet fractures is a DIP joint extensor lag, an intact ORL will serve to passively assist DIP joint extension as PIP joint active extension occurs. 19 P3 Shaft Fracture Trauma at this level, proximal to the nail bed, usually causes an open wound that needs to be supported with external splinting or K-wire and splinting for 3 weeks. Wound care, edema measures, and motion at the MP and PIP joints is encouraged after the first week. Active ROM at the DIP joint can be initiated after 3 weeks if callus consolidation permits. Loss of full DIP joint flexion is usually due to soft tissue contracture of joint structures and dorsal skin scar. Wrapping the digit with coban into an intrinsic minus position and then dipping into paraffin provides simultaneous heat and stretch, which has been shown to have the best effect on soft tissue lengthening. 49 This is followed by blocking exercises for FDP tendon glide. P3 Tuft Fracture Treatment of the tuft fracture, even when comminuted, is relatively simple. Compression around the tip facilitates fragment approximation and diminishes the very painful effect of bleeding and swelling at this level. A thin, protective splint extending to, but not including, the PIP joint is worn for 2 to 3 weeks. Fibrous union is slow to ossify at this level, requiring several months 26 ; however, motion can and should be reintroduced at the DIP level by reducing the length of the protective splint and encouraging joint motion. The more difficult aspect of managing these fractures is the extent of nail bed injury that may be present and require suturing. Dressing changes that do not disturb the repaired nail bed are performed after soaking the tip of the finger in a sterile container filled with saline and part hydrogen peroxide. 19 The finger pulp region is densely innervated with sensory end organs that painfully respond to the initial crush, nail bed damage, and swelling with the development of hypersensitivity to touch. Use of a TopiGel sleeve, once nail bed healing is complete, assists in scar management as well as dampening painful sensory input. Desensitization programs that include vibration, putty press, and texture tolerance are beneficial to accommodate to normal fingertip use. Occasionally, the fracture pattern shows significant displacement of the 2 fracture fragments, requiring ORIF with K-wire fixation for 3 weeks. 2 Protective, supportive splinting, including DIP and PIP joints, initially allows the inflammatory period to resolve. Care must be taken that the splint does not rub against the exposed pin, as excessive irritation can result in a pin tract infection. CONCLUSION Unique to hand anatomy, soft tissues glide in multidirections mere millimeters away from skeletal structures. It is impossible, then, to consider skeletal injury as isolated trauma to bone tissue only. Trauma and fracture displacement can harm surrounding soft tissue structures as well as encase both together in 796 J Orthop Sports Phys Ther Volume 34 Number 12 December 2004