Treatment of Distal Radial Fractures

Transcription

1 Treatment of Distal Radial Fractures Philippe Kopylov, Antonio Abramo, Ante Mrkonjic, and Magnus T agil Contents Introduction Aetiology and Classification History Definition Epidemiology Costs of DRF Classification of DRF Applied Anatomy, Pathology and Biomechanics Normal Anatomy and Fracture Patterns Bony and Ligamentous Anatomy Biomechanical Considerations DRF and Osteoporosis Results-Evaluation Goal of Treatment Objective Parameters Radiographs Subjective Parameters Diagnosis and Treatment Programme Surgery and Indications Pre-Operative Planning Surgical Techniques Closed Reduction Open Reduction Surgical Approach Dorsal Approach Volar Approach Post-Operative Care and Rehabilitation Complications Mal-Union Reflex Sympathic Dystrophy Carpal Tunnel Syndrome Extensor Pollicis Longus Tendon Rupture Other Tendon Ruptures Summary References P. Kopylov (*) A. Abramo A. Mrkonjic M. T agil Hand and Upper Extremity Unit, Department of Orthopedics, Lund University Hospital, Lund, Sweden philippe.kopylov@med.lu.se G. Bentley (ed.), European Surgical Orthopaedics and Traumatology, DOI / _91, # EFORT

2 1676 P. Kopylov et al. Abstract The distal radius fracture (DRF) is the most common fracture in the upper extremity, affecting not only osteoporotic women but also young adults with high energy trauma. A previously rather conservative treatment attitude has nowadays been replaced by more aggressive surgical treatment protocols with open reduction and internal fixation. To treat these fractures optimally, we have to carefully evaluate both the patient and the fracture. Besides the type of injury and fracture, patient age and activity level as well as the functional demands are important to consider in order applying the appropriate treatment in each case. The use of a treatment protocol as the guideline for the choice of treatment is beneficial. Well-conducted conservative treatment with full attention to potential problems still gives good results in selected cases. The main indications to treat the fracture surgically are based on the measured radiographic displacement of the fracture and, in dorsal dislocated fractures, we hesitate to accept a dorsal angulation of more than 10 and/or an ulna plus of more than 2 mm and/or an articular step more than 1 mm In volarly-dislocated fractures only minor displacement is accepted and rarely more than 25 from the neutral plane. The goal of the surgery is to reduce the fracture by a closed method or openly but immediately afterwards to maintain the position during the healing time. Today, the attitude of the Orthopedic world appears to be in favour of open reduction and fixation most often using the increasingly popular volar locking-plate. The indication for surgery is rapidly changing with the volar locking-plate but we must bear in mind that this aggressive surgical method has not been shown to be superior to the older techniques. Treatment using close reduction and external fixation still is a good alternative. In difficult cases it is beneficial to have several methods at hand but most important still is to pre-operatively fully analyze the fracture pattern and the patient needs. Keywords Analysis of results Anatomy pathology and biomechanics Classification Closed treatment Complications Diagnosis Distal Radial fractures Epidemiology Osteoporosis Results Surgical indications and techniques Treatment goals Introduction The Distal Radius Fracture (DRF) represents the fracture of the lower end of the radius and is the most common fracture of the upper extremity. From a relative conservative policy of treatment according to the expected good results of these injuries as reported by Colles and many authors we are facing now a very aggressive treatment with open reduction and internal fixation [1, 2]. There is often confusion between the different fractures types, the character of the injury and not least the patient groups, their age and activity level or expected activity level. We have to be careful and not treat all patients in the same way using the latest implant presented on the market. The best way of treating a distal radial fracture still remains a matter of debate and we are missing evidencebased research arguing for one or the other method. So, where are we today and in what direction are we going? All we know is that the solution to the problem as we know it today will not be definitive and the standard of care will continue to change over the years- hopefully through evidence-based changes. In order to present information to the less experienced surgeons, we will review the history of the distal radial fracture, both the traditional concept of classification and treatment, and the newer treatment algorithms. We will also present our preferred method of treatment. We base our concept on the fact that the primary goal of treatment is the restoration of complete wrist function and for this purpose an anatomic reduction of the fractured distal radius, which has to be maintained during the healing time. But, in all cases the morbidity of the chosen

3 Treatment of Distal Radial Fractures 1677 Fig. 1 Different aspects of DRF. On the left side a two- part fracture without involvement of the articular surface and no volar comminution. On the right side the fracture is intra-articular and comminuted both dorsally and volarly treatment has to be balanced to the magnitude of the improvement and correlated to the patient needs and demand. Primum non nocere (Fig. 1). Aetiology and Classification History Already Hippocrates recognized and described wrist trauma, mainly with a focus on the direction of the dislocations. Initially there was confusion between carpal dislocation and fracture and the first author to recognize a fracture at the end of the radius, and also suggest treating it in a splint, was Jean Louis Petit in the second part of the eighteenth century. Another surgeon, Claude Pouteau, described this injury as a proper distal end radius fracture(drf). Unfortunately his work was not recognized and we have to wait until 1814 for the article by Abraham Colles with his precise description of this injury. In this article, Colles makes the well known statement about the expected good results of such an injury. This first era of describing the DRF was followed by an era of multiple publications and advices about treatment. There were a number of authors who described the different injury mechanisms as well as various reposition manoeuvres and splint designs (Jupiter and Fernandez). These publications have strongly influenced the treatment until today [3]. Only in the last decades other treatment methods like external fixation or open surgery have been suggested in order to improve the results of this common fracture. We do not accept the result as Colles described them and the goal of treatment is now higher. Definition The Distal Radius fracture can be defined as a fracture involving the distal third of the radius. By definition the DRF is a metaphyseal fracture and involves the cortical and the cancellous bone as well as the subchondral cartilage-bearing bone. The different mechanical properties of these types of bone have to be kept in mind when judging the fracture stability and/or the possibility of fixation and stabilization. The definition above excludes the concomitant fracture of the ulna which would make us consider the fracture to be a forearm fracture with other instability problems and special requirement. In practice, we do include an injury of the ulna styloid and/or the stabilizing structure of the Distal Radio-Ulnar Joint (DRUJ), the Triangular Fibro-Cartilage Complex (TFCC).

4 1678 P. Kopylov et al. Most commonly the DRF is a closed fracture involving only the radius but the fracture can be open and associated with tendon, nerve or vascular injuries. The DRF can also be associated with carpal injuries such as ligament tears or carpal bone fractures and the use of CT or MRI has shown a high frequency of these associated injuries. It is important to emphasize the necessity to recognize the associated injuries. The deformation of the wrist after injury gives the diagnosis but only a radiographic examination gives us the opportunity for a proper analysis of fracture type and stability during treatment. Epidemiology DRF are common fractures accounting for about one-sixth of the fractures treated at emergency rooms or one-tenth of the total number of fractures in adults over 35 years. The incidence of DRF is approximately per 10,000 inhabitants annually with females outnumbering males in overall distribution by 4:1. For DRF in younger patients the proportions of men and women are equal. These fractures are often the result of a high energy trauma and should therefore be treated differently from the osteoporotic fractures [4]. The fractures in younger patients are often intra-articular and associated with a high incidence of ligamentous injuries with the scapholunate ligament being the most commonly injured. With increasing age DRF, as well as fractures in general, tend to be more common. The DRF is most common among older women with an incidence of per 10,000 inhabitants annually. Costs of DRF As the fracture is common, it imposes large costs to society. With an increasing proportion of elderlypeople,notonlyinthewesterncommunities but also in the developing countries, the DRF remains an important and increasing economical problem. However, not only the costs of the fracture are of importance, but also the outcome and disability from the patients perspective. Reliable objective measurements are of importance and better outcome instruments need to be developed. Classification of DRF A classification system should be able to recognize and define the injury, suggest a method of treatment and describe the expected outcome. In recent decades, growing knowledge of fracture pathophysiology and new technology have made new classifications necessary [5]. Most DRF s are diagnosed using conventional radiographs. 3-D computed tomography (CT) and magnetic resonance imaging (MRI) are increasingly used especially for more complex injuries but the commonly used classifications are still based only on conventional radiographs. The five most widely used classifications are: 1. Frykman s classification is used frequently in the medical literature. The eight groups are defined by the individual involvement of the radio-carpal and radio-ulnar joints and the presence or absence of a fracture of the ulnar styloid process (Fig. 2). 2. The AO classification emphasizes three basic types, depending on fracture localization. Type A is extra-articular, type B-partial articular and type C accounts for more complex fractures with intra-articular involvement. The main groups (A, B, C) in combination with sub-groups define precisely the fracture. This classification is adaptable for computerized documentation and uses the same principles for all fractures of the long bones (Fig. 3). 3. The Mayo classification deals exclusively with intra-articular fractures and describes four types, classified according to the involvement of the specific articular surfaces of the distal radius. 4. The Melone classification highlights the so-called medial complex which appearance predicts both classification type and gives a prognostic view.

5 Treatment of Distal Radial Fractures The Fernandez classification is based on the mechanism of injury and developed to be practical, to identify children s equivalent injuries, to include associated lesions, take into account the stable versus unstable patterns and to be memorable to provide general recommendations for treatment. In the Bending type (1) of fracture one cortex of the metaphysis fails due to tensile stress and the opposite cortex undergoes comminution, in the Shearing type (2) there is a simple articular fracture, in the Compression type (3) the fracture of the articulation shows impaction of the subchondral and metaphyseal bone. In the Avulsion type (4) the fracture involves the ligaments attachments and there is a radiocarpal fracture dislocation. The Combination type (5) is an association of the other types and in relation with high-energy injuries (Fig. 4). Fig. 2 Frykman Classification Authors Preferred Classification. As the classifications have been shown to correlate poorly with final clinical outcome and the inter-observer reliability and intraobserver reproducibility of different radiographic classifications are low, we use classifications only for research and publications. In our daily clinical work we analyze the fracturedislocation grade before and after re-position, A1 B1 C1 A1.1. A1.2. A1.3. B1.1. B1.2. B1.3. C1.1. C1.2. C1.3. A2 B2 C2 A2.1. A2.2. A2.3. B2.1. B2.2. B2.3. C2.1. C2.2. C2.3. A3 B3 C3 Fig. 3 AO classification A3.1. A3.2. A3.3. B3.1. B3.2. B3.3. C3.1. C3.2. C3.3.

6 1680 P. Kopylov et al. Fig. 4 Fernandez Classification I II III IV V we carefully define the fracture lines and their localizations. All these elements are correlated to patient age and bone quality and in order to evaluate the potential instability of the DRF. This stability index helps us to better define the treatment proposed to each patient. Applied Anatomy, Pathology and Biomechanics Normal Anatomy and Fracture Patterns The distal radius contains three important concave surfaces. Two of them articulate with the carpus, the lunate and scaphoid fossae, and one, the sigmoid notch with the ulna. All three joints are stabilized by common or individual ligaments, which will tighten in motion and load, preventing motion of the bones in the joints outside their natural range. With osseous incongruence or ligamentous rupture the load transfer from the carpus to the radius or from the radius to the ulna will be disturbed and unphysiological stresses can cause degeneration of the cartilage and, in time, to development of osteoarthritis. The scaphoid fossa is triangular in shape with its apex pointing to the radial styloid and a small ridge separates it from the smaller lunate fossa. The tolerance for mal-alignment is limited and the function of an intact scapho-lunate ligament is important. The sigmoid notch articulates with the convex ulnar head and the DRUJ can be seen as a separate

7 Treatment of Distal Radial Fractures 1681 Fig. 5 Drawing of the Distal End of the Radius. (a) Dorsal view with the Lister tubercle. (b) Volar view. Note the watershed line which is the distal limit where a volar plate can be inserted. (c) Ulnar view which shows mainly the articular surface with the ulna. (d) Articular view with the articulated surface to the scaphoide and lunate and the ridge between the two fossae a b c d joint in relation to the radiocarpal joint. Also in the DRUJ joint, the ligamentous function of the TFCC and the ulnotriquetral ligaments are important but the joint is less constrained than the radioscaphoid and the radiolunate joints. In unloaded motion the surfaces translate relative to each other but the TFCC tightens up when a load is resisted. The tolerance for partial ligamentous insufficiency appears to be higher since ligament injuries are common in radial fractures and the symptoms most often subside in time but total ruptures lead to painful instability and osteoarthritis. An interindividual variation regarding the osseous joint congruity seems to matter in developing a symptomatic instability or not (Fig. 5). Bony and Ligamentous Anatomy The metaphyseal flare starts approximately 2 cm proximal to the wrist joint with the water shed line and the distal part accommodates the origin of the stabilizing volar ligaments, mainly the radial collateral, radio-capitate and radio-triquetral ligaments. At the ridge between the two fossae, the important radioscapholunate ligament originates at the Testut tubercle, which can be seen at the lateral radiogram as the volar teardrop. Proximal to the watershed line, the volar radial surface flattens and accommodates the pronator quadratus muscle. Although metaphyseal bone, the cortex is thicker on the volar side than on the dorsal

8 1682 P. Kopylov et al. Fig. 6 CT of the distal radius of a 49 years-old man showing the thickness of the cortical bone. Note the thin cortical bone on the dorsal and radial border making a more stabile construct for a plate possible. The dorsal side, with the prominent Lister tubercle, is convex and acts as a fulcrum for the extensor tendons, which lie close to the bone, thereby at risk for penetrating screws from the volar side. The radial styloid has an impression for the APL and EPB tendons immediately radial to the Lister tubercle. A restored anatomy is considered to be of importance for the return of function but the anatomical position rarely has been shown to be a good predictor of the final result. For minor anatomical deviations there seem to be a quite substantial tolerance and a good final result can be achieved even with dorsal compression and intra-articular step-offs. Major deviations from the normal anatomy after fracture healing, from experience, mean larger problems for the patient including cosmetic suffering even if evidence is missing in the literature. Biomechanical Considerations In humans the metaphyseal bone is found at the ends of a long bone where compressive forces are transmitted from the articular cartilage to the condensation of thicker bone subchondrally out in the metaphyseal bone to the cortical bone at the diaphysis. The subchondral bone supports the articular cartilage and retains its strength also in the osteoporotic and elderly patient. The subchondral bone is used in some of the surgical techniques as pins, pegs and screws are placed immediately under the subchondral bone to secure the position. In a die punch fracture the proximal carpal bones are pressed into the distal radius and fracture the subchondral bone. Manipulation alone cannot reduce these fractures, which have to be opened. The depressed subchondral bone is elevated and the void beneath is filled with bone graft or bone substitute. Also shearing fractures like a Chauffeur s fracture involve the subchondral bone but these fractures are most often non-comminuted and simpler to reduce. Although we are aware of the fact that cartilage does not heal ad integrum, minor step-offs do not seem to cause residual symptoms. In the long term they can lead to a radiographical osteoarthritis and therefore are preferably avoided. Incongruence, due to an osseous mal-alignment can also lead to osteoarthritis (Fig. 6). DRF and Osteoporosis Over the last decades there has been an increase in DRF incidence, especially in the age group greater than 60 years. The higher incidence among older women could be explained by

9 Treatment of Distal Radial Fractures 1683 the increasing incidence of osteoporosis. A screening of patients with wrist fractures between the ages of years revealed that only 19 % had normal bone mineral density (BMD) in the hip and vertebrae. The occurrence of a DRF can be used as a predictor for a later hip fracture. In a Swedish study an overall relative risk to sustain a hip fracture after a previous DRF was 1.54 for women and 2.27 for men and in an American study the relative risk for a hip fracture was 1.4 for women and 2.7 for men. Also men have osteoporosis according to these studies with increasing incidence with increasing age. Medical treatment of osteoporosis is successful to reduce the risk of future osteoporotic fractures [6, 7]. Results-Evaluation Goal of Treatment The goal of treatment of DRF is to restore the function of the wrist, not only the radiographic appearance. The surgical treatment aims to anatomically reduce the fracture and maintain the reduction during the healing time. But what exactly is an anatomical reduction and what exactly is a restoration of the function? Can we accept some residual mal-position in the fracture during healing? Can we expect a total restoration of the wrist function? What are the results of DRF and how can we measure them? The final result of a fracture can be difficult to define and measure. The type of the injury, the expectation of the patient and/or the medical team may have an impact on the perceived end result [8]. Various modalities have to be considered, such as subjective, objective and economical outcome. To fully evaluate any diagnosis or treatment option, we believe both subjective parameters out of the patient s perspective as well as objective clinical assessment and radiographic examination are of interest and should be used. In our practice, but also for research purposes we use the following tools assessing the results. Objective Parameters These parameters should be analyzed in comparison with the non-injured contra-lateral side. The range of motion is measured in the three axes of rotation around the wrist joint. Extension and flexion as well as radial and ulnar deviation take place in the radio-carpal joint and forearm rotation in the distal and proximal radio-ulnar joints. Grip strength is measured with a dynamometer, expressed in kilogram and related to the strength of the contra-lateral hand. Radiographs Radiographs have been shown to correlate poorly with final clinical outcome and the inter-observer reliability and intra-observer reproducibility of different radiographic classifications is low. In some studies an association has been shown between the initial radiographs and the final radiographic outcome. Lafontaine et al. created an instability index incorporating an increased number of instability factors on the initial radiograph, i.e., dorsal angulation more than 20, dorsal comminution, intra-articular radio-carpal fracture and associated ulnar fracture and an age over 60 years were all correlated with worse radiographic outcome. Mackenney demonstrated that ulnar variance, metaphyseal comminution and patient age were predictors for the radiographic outcome, as was the dorsal angulation as a predictor in primary displaced fractures. In a recent study, the radiographic appearance in the initial radiograph, radial shortening > 2 mm, dorsal angulation >15, and radial angulation >10 were each significantly associated with a poorer DASH score (Fig. 7). Subjective Parameters In order to try to catch smaller but clinically more important changes, we use a region-specific outcome scoring system, the DASH which is one of the most commonly used region specific scoring

10 1684 P. Kopylov et al. Fig. 7 Drawing showing the cut-off limits for radiographic mal-position qualifying for surgery: in dorsally dislocated fractures dorsal angulation >10 and/or Ulna+ > 2mm and/or articular step >1 mm; in volar dislocated fractures Volar dislocation >25.(a) Measurement of the ulna + which is the difference in length of radius and ulna in DRUJ. (b) Measurement of the volar/dorsal inclination of the articular surface of the radius a b systems for the upper extremity. The shorter Quick DASH, nowadays is more commonly used and consists of eleven questions. For the wrist specifically, a joint-specific outcome instrument exists the Patient Rated Wrist Evaluation (PRWE), which has a somewhat higher specificity than the DASH [9 12]. Diagnosis and Treatment Programme A standardized treatment programme, based on the radiographic appearance, but taking in account the age and the demands of the patients was developed by The consensus group for distal radius fracture in southern Sweden in The group consisted of dedicated surgeons from the Orthopaedic and hand surgery departments in south of Sweden with special interests in the treatment of DRF. The treatment protocol is meant to be used as a guideline for treatment but a strict compliance to it is not expected. In a prospective follow up of a large number of patients collected from the previously mentioned DASH registry, the treatment protocol was found to be of value to select the optimal treatment for each patient (Fig. 8). DRF Author s Treatment Programme (1) Diagnosis: In most cases the diagnosis of DRF is easy. The classical patient history, deformation patterns of the wrist and the localization of pain leave no doubt. But a full examination of the elbow, forearm, hand and wrist has to be conducted in all cases in order to search after and recognize associated lesions (tendon, vascular, nerves injuries, concomitant joint dislocation, carpal injuries). The radiographic examination (frontal and side views without rotation of the forearms) confirms the diagnosis and gives a strong indication regarding the possibilities to reduce and stabilize the fracture. After diagnosis all displaced fractures have to be reduced. Displacement: Displacement in dorsal dislocated fractures means dorsal angulation > 10 and/or Ulna+ > 2 mm and/or articular step >1 mm. Displacement in volar dislocated fractures means volar angulation >25.

11 Treatment of Distal Radial Fractures 1685 Fig. 8 The southern Sweden treatment protocol for DRF. When selecting different treatments the patient s age and demands also have to be accounted for Fracture type Minimally or non-displaced Distal radius fracture treatment protocol Displaced a High energy trauma \highly comminuted Volar Barton Primary treatment Closed Reduction Reduced Still displaced Short arm splint Follow up Clinical\ray control after 7-10 days Always internal fixation Final treatment Displaced Operation internal or external fixation Still in place Conservative treatment Short arm splint for another four weeks a Displaced=dorsal angulation >10 and/or Ulna + > 2mm and/or articular step >1mm or volar angulation >25 Re-position: The reposition is performed using gentle traction after local anaesthesia into the haematoma or even better intravenous local anaesthesia (Bier Block). The traction by itself can provide pain relief to the patient but has to be maintained for at least 10 min. Only after that time further reposition and manipulation should be done, if necessary. If excessive volar flexion is needed to reduce the fracture, immobilization of the wrist in this position should be avoided. In flexion and ulnar deviation the lunate maintains the fracture in place, after blocking the lunate in place, an extention of the wrist in the mid-carpal joint can be done in order to put the wrist in a safer immobilization position. If the closed reduction fails an open technique can be necessary. Immobilisation: Even if the reposition most often is easy, the immobilization remains more problematic, knowing that the position of fracture system has to be kept during healing time. In dorsally dislocated fractures a dorsal cast and in volarly dislocated fractures a volar cast is applied and new radiographs confirm the fracture re-position. If the fracture is reduced according to the displacement

12 1686 P. Kopylov et al. criteria, no major volar or dorsal comminution are noted and no associated injury diagnosed or suspected, the patient can be treated conservatively with planned immobilisation time of 5 weeks. Patient information and training with cast: The patient has to be informed about hand and finger oedema and given an exercise programme to prevent it. Also exercises for the elbow and shoulder are given to prevent reflex dystrophy. Clinical and Radiographic follow-up: Inall cases the patient is reviewed after 7 10 days in order to be able to diagnose and treat extensive swelling and reflex dystrophy risk. A new radiographic examination reveals any loss of reduction. If the displacement criteria are not met another method of treatment than cast treatment is proposed and discussed with the patient. A new re-position and new cast treatment is rarely successful. Remember, we treat patients not X-rays and the position of the fracture on radiographs is not by itself an operation indication. The needs and demands of the patient, patient age and bone quality all have to be taken into account. Surgery and Indications Surgery can be necessary if the closed reduction failed and/or if the cast immobilization failed [13]. The Orthopedic treatment with immobilisation in cast only cannot be continued in the following situations: The re-position does not meet the criteria: dorsal angulation <10 and/or Ulna+ <2mmand/ or articular step <1mm, and in volarly dislocated fractures- volar dislocation <25 The initial position is lost at follow-up A volar and/or dorsal comminution exists The DRF is associated with carpal bone or carpal ligaments injuries The DRF is associated with an ulnar fracture more than only the styloid Special needs and demands of the patient Bilateral DRF (eventual) Multi-trauma patients with many fractures In these cases a surgical treatment has to be chosen. A re-reposition with new cast immobilisation never gives adequate results. Pre-Operative Planning When surgery is indicated according to treatment protocol and has been discussed with the patient careful planning should be done. The operation can be done as day-care surgery in young patients provided the post-operative pain is well controlled and a regional anaesthesia is then recommended. The surgery is not an emergency operation and should not to be performed late in the night without a complete and qualified team. A good position of the patient on the table, exsanguination and C-arm are mandatory. In special cases and if the surgeon is trained, arthroscopy can be used to optimize the intra-articular fracture reduction. Things to consider during the pre-operative planning: The possibility to reach an anatomical reposition and provide adequate fixation, which permits an early mobilization without risk of secondary displacement The type of anaesthesia and post-op. pain relief To reduce open or closed The type of osteosynthesis, depending on the fracture pattern The incision and approach to be used. Surgical Techniques Closed Reduction External Fixation External fixation of DRF has been in use for more than three decades. It is still used today by many and considered to be the standard method for operative treatment of the fracture and for this reason it can be chosen as the method of reference to which newer methods can be compared. External fixation uses ligamentotaxis to both reduce as well as to hold the fracture in position

13 Treatment of Distal Radial Fractures 1687 Fig. 9 External fixation. In this much-comminuted distal radius fracture associated with an ulna shaft fracture the external fixator gives a very good stabilization. The ulna is fixed with a plate. A secondary bone graft with plate fixation has to be done after removal of the external fixator during healing. Better results have been presented with the external fixation than with a below- elbow cast evaluated at 2.5 years post-fracture, but the external fixation was noted as having more complications. The external fixator can be used also for complex and intraarticular fractures. The recommended time for immobilization varies, ranging from 4 weeks to 7 8 weeks. In general, long immobilization time increases the risk of reflex sympathetic dystrophy (RSD). At the author s department we aim at a 5 weeks immobilization period. The traction of the wrist ligaments may cause stiffness and therefore dynamic fixation with an articulated device or non-bridging fixation has been proposed [14 18]. External Fixation Surgical Technique Determine the position of the external fixator to achieve the optimal length. The fixator should not be fully distracted or fully compressed when determining pin positions. When inserting the pins care has to be taken not to injured nerves, especially radial nerve proximally or tendons. To avoid injuring the radial nerve an incision could be used carefully dissecting and protecting the nerve while introducing the pins. Aim for an angle of approximately 45 in aspect of the dorsal cortex of respective metacarpal and radius. Use pin guides to insert the pins both distally and proximally. Apply the fixator with the clamps and screws loose. Reduce the fracture and lightly tighten the screws and clamps. Check the fracture position under fluroscopy and appreciate the traction applied by the distance in-between the carpal bones. After-tighten the screws (Fig. 9). Pinning Other closed reduction techniques includes fixation of the fracture by pinning. Various techniques have been described such as intrafocal pinning, intrafocal intramedullary pinning, or pinning in combination with external fixation. It has been reported to result in large number of mal-unions, but also satisfying results have been reported with the technique. In the Cochrane meta-analysis of all randomized studies in DEF, percutaneus pinning of DRF is considered to have a high rate of complications. Compared to volar locking plates, intrafocal pinning in one comparative study was shown to be inferior. In another study in extra-articular fractures in patients over 60 years, pinning was found to provide only a marginal improvement in the radiological parameters compared with immobilisation in a cast alone. In all cases of pinning an additional cast immobilisation for a period of 5 weeks is mandatory.

14 1688 P. Kopylov et al. Fig. 10 The Kapandji pinning technique. The pins are introduced in the fracture site on the radial (a) and dorsal (b) border. The fracture is reduced with the help of the pins and fixed both radially and dorsally (c and d) a 2 b c d Kapandji Pinning Surgical Technique Under fluoroscopy, pins are driven into the fracture site in a proximal to distal direction [20, 21]. Pins are introduced in the desired direction to correct the dislocation of the fracture. To correct loss of dorsal angulation, drive pins into the dorsal cortex and to correct the loss of radial inclination, drive pins along the radial cortex. Make sure the incisions are long enough so the pins will not be driven across the extensor tendons (Fig. 10). Open Reduction The primary goal of open reduction is to reach an anatomical reposition. The reduction has to be associated with a proper fixation whose goal is to stabilize the fractures during the whole healing and permit early, if possible immediate, mobilization. Plates For volarly-dislocated fractures a volar plate is used preferably. For other types of DRF, other techniques have been considered. Standard AO-plates and screws can be used with good results. To get good stability, usually two or more columns of the radial cortex have to be fixed to achieve good results. With the introduction of implants designed specifically for the distal radius, the open technique has become increasingly popular. The Pi plate, named after its shape like the Greek symbol p, is designed to fit on the dorsal side of the radial metaphysis. Good results have been reported but interference with the extensor tendons and high complication rates have been noted. This has made a change in design of the plate necessary [22 26]. Fragment-Specific Fixation A fragment-specific system addresses the radial and ulnar columns separately as well as single

15 Treatment of Distal Radial Fractures 1689 Fig. 11 Pre- and post-operative radiographs of a DRF surgically treated with open re-position fixation with Fragmentspecific device fracture fragments both dorsally and at the volar rim by a combination of plates, pins and screws. It is primarily based on pinning of the fracture, but since additional stability is needed to prevent the pins from bending or the fragments from sliding on the pins, a stabilizing plate to secure the pins has been added. In addition, wire forms to support the subchondral bone or small fragments can be used. The system is low profile and offers good stability. The fracture is approached through a radial incision between the first and second dorsal compartment for placement of the pins and fixation with a radial pin-plate and secondly through a second incision through the fourth compartment for fixation with wire forms, buttress pins and ulnar pin-plate. A volar approach can also be performed to secure the fracture with a volar buttress pin. The surgical approach is determined by the type of fracture and the type of fixation needed to address the fragments (Fig. 11) [27, 28]. Volar-Locking Plates The newest and most widely used concept, the volar-locking plates with angle stable screws or pegs offers stability and a safe approach to the fracture. The volar-locking plate has, in biomechanical testing, been shown to be sufficiently stable for fixation of the dorsally comminuted fracture and has been shown to offer equivalent stability when compared to the fragment specific fixation [29 33]. The best stability is provided by a combination of a volar-locking plate with the fragment-specific system. Good clinical results have been reported in a few case series but complications such as tendon ruptures of both flexor and extensor tendons have been reported. Great attention is needed to place the plate correctly underneath pronator quadratus and absolutely avoid perforation of the dorsal cortex by the screws (Fig. 12). Bone Grafts and Bone Cements After open reduction, a void is commonly seen in the metaphysis and the fixation needs to be

16 1690 P. Kopylov et al. Fig. 12 Fracture treated with a volar plate combined with a bone graft or bone substitute to fill the gap caused by the impacted osteoporotic bone [34, 35]. Bone Grafts The most commonly used bone graft is an autograft, often harvested from the iliac crest. An autograft has the advantage of being both osteoconductive (allows bone to grow into it) as well as osteoinductive (induces formation of new bone). The major disadvantage is the limited amount of bone available and post-operative morbidity from the donor site. Complications can occur such as minor infections or seromas in 10 % and even major complications requiring hospitalization in 6 % of patients. Therefore there is a need for an alternative to autograft. The risk of transmitting viral or today unknown diseases has made the use of human and even animal grafts less attractive. Bone Substitutes Synthetic bone substitutes have the advantage of comparable mechanical properties while diminishing the risk for transmittal of diseases. Calcium sulphate (plaster of Paris) was commonly used since the late nineteenth century but has the disadvantage of having poor mechanical resistance and fast resorption rate. Slowly resorbing and stronger substitutes have been developed. To mimic bone various bone substitutes using calcium phosphate, the major mineral component of bone, have been developed. It is used as hydroxyapatite Ca 10 (PO 4 ) 6 (OH) 2, which is poorly soluble and as tricalcium phosphate Ca 3 (PO 4 ) 2, which is relatively soluble, or a combination of both. These substitutes can be obtained in granules or monoblocks but to facilitate minimal invasive surgery injectable substitutes have been developed. All the above mentioned types of bone substitutes are highly biocompatible but have no osteoinductive properties in contrast to bone graft. This can, however, be dealt with when designing composite grafts, combining bone substitute either with substances increasing in-growth such as osteogenic proteins (BMP) or bone marrow aspirate or substances reducing resorption such as bisphosphonates. Surgical Approach The choice of the approach to be used depends on two factors, the analysis of the fracture pattern and the special need of the used instrument itself.

17 Treatment of Distal Radial Fractures 1691 Classically, a dorsal approach with dorsal fixation was used for the dorsally-displaced fractures and a volar approach was used for volarly-displaced fractures. The volar locking devices or the fragment specific system give better possibility and variety of approach choices. We also have to consider that on the dorsal aspect of the radius the tendons lies direct on the bone and there is neither room for bulky plates and instruments nor perforating screws coming from volar side. On the contrary the flexor tendons are not in contact with the bone except at the most distal volar lip of the radius. The pronator quadratus muscle can also be seen as a good protection of the tendons. Dorsal Approach Several fracture patterns indicate a need for a dorsal approach to the radius. These includes comminuted intra-articular fractures involving the dorsal and radial cortex. To approach the radial side of the distal radius an approach between the first and second dorsal compartment is used. Care should be taken not to injure the dorsal branches of the radial nerve. The incision can be extended into the first compartment and through the brachioradialis tendon to reach the volar cortex. To reach the ulnar part of the radius an approach between the third and the fourth compartment can be used. The extensor retinaculum can be opened in a stepwise manner making it possible to elongate the retinaculum at the end of the operation if needed and also making it possible to reconstruct the pulley for the EPL (Fig. 13). Volar Approach The fracture is approached from the volar side using the modified Henry approach through the flexor carpi radials (FCR) tendon sheath. This offers an easy access to the volar part of the radius [36]. An incision is made over the FCR-tendon and if necessary prolonged distally radially. The FCR tendon sheath is opened and the tendon is retracted ulnarly. The bottom of the sheath is opened with care taken not to injure the cutaneous branch of the median nerve which in most cases if found on the ulnar side of the tendon sheath. The flexor tendons and muscles of the forearm are retracted ulnarly and the pronator quadrates muscle (PQ) is transected on its radial side lifted from the radius and held ulnarly throughout the operation. The fracture is reduced and fixed with the volar-locking plate. Before final fixation the position of the distal screws should be carefully checked under fluoroscopy. They should be placed in close relation to the subchondral bone of the radius but not penetrating into the joint. To check the position of the joint line the arm should lifted from the operating table. In order to reduce and fix the fracture two options are available. Either a primary placement of the distal screws first and with the plate in place distally reduce the fracture and finally insert the proximal screws. The other option is to first reduce the fracture. Place the plate and insert the screws starting proximally (Fig. 14). In both cases be careful while tightening the proximal screws not to displace the fracture. A common problem is the ad latus mal-position of the radius shaft which dislocates ulnarly because of the traction of the PQ. This can be reduced by radial traction with a hook while tightening the screws (Fig. 15). Post-Operative Care and Rehabilitation Active mobilization of the fingers is started immediately after surgery. The DRF surgery is usually day surgery. However the post-operative pain control is mandatory to avoid complications such as swelling and reflex sympathic dystrophy (RSD). For this reason a regional plexus block is a good alternative for surgery giving a good pain relief post-operatively. Sometimes opiate medications are needed and the patient has to stay overnight at the hospital. The patient has to be informed about swelling problems and instruction given for mobilization of fingers elbow and shoulder. The patient is treated with a short-arm cast for 2 weeks after open surgery. Five weeks of immobilisation are needed when treating the patient with external

18 1692 P. Kopylov et al. a b c d e f Fig. 13 Dorsal and radial approach. On a right wrist the radial (a) and dorsal incision (b) are designed in order to dissected free the tendons Abductor pollicis longus and Extensor Pollicis Brevis on the radial border (c), Extensor Digitis Communis and Extensor Pollicis Longus on the dorsum of the wrist (d). The fracture can be reduced and the osteosynthesis placed radially under the tendons (e) and dorsally close to the bone bridging the dorsal comminution (f) fixator or pins and cast. After cast removal the patient only uses a removable soft splint and active mobilization of the wrist is started with the goal of reaching full motion including pronation and supination within the first 3 months. Usually the physiotherapist only needs to inform the patient and control the progress of function recovery. In some case more intensive physiotherapy is needed. Pain should be monitored for RSD and other complications such nerve compression or tendon irritation avoided. Progressive loading with the injured wrist can be started quite early with new fixations devices, however full loading should not be allowed before 8 weeks. DRF Author s Treatment Programme (2) Surgically indications: Surgery can be necessary if the closed reduction failed and/or if the cast immobilization failed. For this reason we recommend to keep in mind the treatment protocol and the acceptable mal-position on radiographs dorsal angulation >10 and/or Ulna+ >2 mm and/or articular step >1 mm,involar dislocated fractures Volar dislocation >25.In all cases of volar and/or dorsal comminution surgery has to be considered. Associate carpal bone injury, finger or metacarpal fractures or DRF combined with an ulna fracture other than only styloid fractures are strong indications for

19 Treatment of Distal Radial Fractures 1693 a b c d e f Fig. 14 Volar approach. On a right wrist the incision is longitudinal over Flexor Carpi Radialis tendon (a and b). Underneath FCR the flexor finger tendons and the medianus nerve can be recognized (c) and pushed ulnarly in order to see the Pronator Quadratus muscle (d) which is detached most radially eventually with a piece of Brachio radialis tendon in order to make the resutur more easy. The fracture is now free (e) andcan be reduced the radius be prepared and the osteosyntheses put in place (f) surgery. The decision for surgery is never made with radiographic evaluation only. The patient has to take part in the decision after information and appreciation of the morbidity of the proposed treatment. Surgical methods: In our department closed reduction with following pin fixation associate with cast are almost never used. The external fixation, nowadays more seldom used, still has indications in very comminuted open metaphysis fractures with a bone defect or in old patients when the radius fracture is associated with a distal ulna fracture. When decision for surgery is made we recommend an open procedure with open re-position and osteosynthesis in order to reach an anatomical reduction and a stable fixation which allows early mobilization. Choice of osteosynthesis: Volar-locking plates can be used in almost all DRF which need surgery. In very distal fractures a plate with a variable angle for the locking screw can

20 1694 P. Kopylov et al. Fig. 15 The ulnar dislocation of radius shaft has to be reduced by traction in the radial direction of the shaft, not by pulling the distal radius ulnarly be necessary. In our department we have good experience of the fragment- specific fixation and strongly recommend its use in DRF with volar distal comminution, tear drop fractures or fractures of the dorso-ulnar border with involvement of the DRUJ. We also consider a good indication to use this device and a radial pin plate is in chauffeur s fractures and when an ulnar dislocation of the proximal radius shaft fracture occurs. The osteosynthesis of ulna styloid is absolutely not mandatory. The fixation with canulated compression screws or wire band technique is only necessary in fracture of the base of the styloid with instability of the DRUJ. Radius Osteotomy: We consider radius osteotomy as a part of the surgical treatment of DRF and proposed particularly in early or late mal-unions using in combination Bone substitute and osteosynthesis. Complications Mal-Union Malunion is a major cause for residual symptoms and appears in about 5 % of fractures. The patient suffers from decreased range of motion and pain, especially at the ulnar side of the wrist. The cause for the symptoms is the malunion resulting in an incongruence of the distal radio-ulnar joint. Apart from the symptoms above these patients suffer from decreased grip strength and also a poor cosmetic appearance. The common treatment option for malunions is an osteotomy of the distal radius. A volar approach for the dorsally mal-united distal radius fracture is today an increasingly popular choice since the increase in volarlocking plate popularity as the fixation of choice for DRF. The healed fracture is cut at the fracture site using an oscillating saw and a correction of the length and/or angle is done using an opening-wedge technique. In some cases when there is an operation performed at the ulna, such as a Darrach (Ulnar head resection) or a Kapandji-Sauvee (arthrodesis of the DRU-joint and osteotomy of the ulnar neck), a closing-wedge can be used. An iliac crest bone graft is often used to fill the gap, either as a single block of cortico-cancellous bone or as a non-structural cancellous graft. The donor site problems with pain, infection risk and nerves injury are drawbacks. A few reports have been written on the use of bone substitute for distal radius osteotomies but mainly in small series. Our personal experience of bone substitutes in

21 Treatment of Distal Radial Fractures 1695 these cases has been good and we rarely use bone graft when performing a distal radius osteotomy [37 41]. Therefore to prevent the patient from developing CTS the wrist should be immobilized in neutral position. Reflex Sympathic Dystrophy Reflex sympathic dystrophy (RSD) appears after a distal radius fracture in about 2 3 % of the cases. In the literature there are reports on as high incidence as 24 % but also as low as 1 %. An active prevention programme is perhaps the most important way to decrease the number of patients with RSD. All patients should be instructed to active motion of the fingers, elbow and shoulders directly after admission. Early follow-up is needed to find early cases with RSD and to start an early prevention programme with intensified physiotherapy. Extensor Pollicis Longus Tendon Rupture The extensor pollicis longus (EPL) rupture after distal radius fracture is a known complication, however not very common. It often occurs in non-displaced fractures and an increased pressure caused by bleeding into the third extensor compartment is thought to be the cause. The patient often notices the inability to extend the thumb 1 2 months after the fracture. The treatment of choice is a transfer of the extensor indicis proprius tendon to the extensor pollicis longus tendon. Carpal Tunnel Syndrome Carpal tunnel syndrome (CTS) is one of the most common complications from distal radius fracture and occurs in about 5 6 % in surgically treated cases. Careful monitoring in the postoperative period will reveal cases in need of surgery but most cases with initial CTS symptoms heal spontaneously. In cases with no improvement within the first days or worsening of the symptoms a carpal tunnel release is performed. The need for prophylactic release of the median nerve when performing surgery on the fracture is debated. However as the cases of CTS are relatively few after surgery and the condition is rather benign and easily treated we recommend that prophylactic release is not performed. Another aspect in avoiding carpal tunnel syndrome is the position of the hand when the fracture is treated in a cast or external fixator. With the wrist in neutral position the pressure in the carpal tunnel in patients with a distal radius fracture is 18 mmhg, while it increases with flexion and extension of the wrist. In 20 of flexion the pressure is 27 mmhg and in 40 of flexion it is 47 mmhg. In extension of 20 it is 35 mmhg. Other Tendon Ruptures With the increasing use of hardware in the treatment of distal radius fracture there has been reports on other tendon ruptures. Patients treated with external fixators have been reported to occasionally suffer from ruptures of extensor tendons. The PIplate and other bulky plates on the dorsum of the wrist on occasion cause extensor tendon ruptures. The volar-locking plates are also known to cause tendon ruptures both on the volar and the dorsal side of the wrist. Care should therefore be taken when placing the screws and the plate. The distal screws should not penetrate the cortex on the dorsal side and even 1 mm of penetration could cause tendon ruptures due to the tendons close relation to the radius on the dorsal side. On the volar side the plate should not be placed to distally as the radius curvature will cause the plate to protrude distally and is a potential cause of tendon injuries. Summary DRF, defined as a fracture affecting the end of the radius, is a common fracture; however the Orthopedic surgeon has in practice to face