Distal radius fractures raises considerable interest and

Transcription

1 Original Article Two peg spade plate for distal radius fractures A novel technique Sharad M Hardikar, Sreenivas Prakash, Madan S Hardikar, Rohit Kumar Abstract Background: The management of distal radius fractures raises considerable debate among orthopedic surgeons. The amount of axial shortening of the radius correlates with the functional disability after the fracture. Furthermore, articular incongruity has been correlated with the development of arthritis at the radiocarpal joint. We used two peg volar spade plate to provide a fixed angle subchondral support in comminuted distal radius fractures with early mobilization of the joint. Materials and Methods: Forty patients (26 males and 14 females) from a period between January 2009 and December 2011 were treated with two peg volar spade plate fixation for distal radius fracture after obtaining reduction using a mini external fixator. Patients were evaluated using the demerit point system of Gartland and Werley and Sarmiento modification of Lindstrom criteria at final followup of 24 months. Results: The average age was years (range years). Excellent to good results were seen in 85% (n = 34) and in all patients when rated according to the demerit point system of Gartland and Werley and Sarmiento modification of Lindstrom criteria, respectively. Complications observed were wrist stiffness in 5% (n = 2) and reflex sympathetic dystrophy in 2.5% (n = 1). Conclusions: The two peg volar spade plate provides a stable subchondral support in comminuted intraarticular fractures and maintains reduction in osteoporotic fractures of the distal radius. Early mobilization with this implant helps in restoring wrist motion and to prevent development of wrist stiffness. Key words: Colles fractures, distal radius fractures, external fixators, volar plates MeSH terms: Fracture fixation, bone plates, radius fractures Introduction Distal radius fractures raises considerable interest and debate amongst orthopedic surgeons. It is an injury seen with high frequency, representing approximately one in six cases seen in the emergency department. 1 For years, distal radius fractures were injuries assumed to be colles fracture and warrant no more than a cast. 1 Various treatment modalities have been devised ranging from cast immobilization, percutaneous fixation, external fixation, open reduction and internal fixation to arthroscopic Department of Orthopaedics, Hardikar Hospital, Pune, Maharashtra, India Address for correspondence: Dr. Rohit Kumar, 1160/61, Hardikar Hospital, University Road, Shivaji Nagar, Pune , Maharashtra, India. E mail: rohit @yahoo.co.in Quick Response Code: Access this article online Website: DOI: / internal fixation. The amount of axial shortening of the radius correlates with the functional disability after the fracture. 2 Furthermore, articular incongruity has been correlated with the development of arthritis at the radiocarpal joint. 3 Malunion of the fracture distal radius has been associated with pain, stiffness, weak grip strength and carpal instability. Long term consequences include degenerative arthritis in up to 50% of patient with even minimal displacement of fracture fragments. 4 Conventional T plates and locking plate system rely on distal screws for stability. They can result in loss of reduction that is, axial shortening or dorsal or volar angulations when wrist mobilization is started. This is due to an unstable interface between the plate and screw head referred to as toggling. In order to address this problem of loss of reduction on early mobilization, many new plates have been designed, which provide a fixed angle subchondral support under the scaphoid and lunate fossae which are the areas of maximal axial stress. Hence, we designed a two peg volar spade plate wherein two volar pegs are fused to the plate to provide an angular stable support to the distal articular surface. Also, being broad on their distal aspect, these plates provide more contact Indian Journal of Orthopaedics September 2015 Vol. 49 Issue 5 536

2 support to the comminuted distal radius, corresponding to its anatomical shape. The plate allows two 2.5 mm screws to be inserted on either side of the pegs to provide a total of 10 mm subchondral support. The plates are not side specific, and the same plate can be used on either left or right radii, thus being universal. The plate is comparatively thinner (1.5 mm) than locked plates (3.5 mm) to suit the Indian population. The modification of the design prevented the above complications of locked and other buttress plates. This study evaluated that two peg volar spade plate for the fixation of comminuted osteoporotic and malunited fractures of the distal radius in terms of functional and anatomical outcomes. Materials and Methods Forty five patients were enrolled in the study who fulfilled the inclusion criteria, out of which five patients were lost to followup of 24 months, hence excluded. This retrospective study included 40 patients of distal radius fractures operated with two peg volar spade plate between January 2009 and December Both males and females, aged between 20 and 75 years and fractures with articular/metaphyseal comminution or impaction that is, AO/ASIF classification types A2, A3, C1, C2 and C3, osteoporotic fractures, malunited colles with manus valgus were included. Type B fractures, patient who did not complete the followup criteria or who did not give consent, were excluded. Patients were regularly followed up at 2, 4, 6 and 8 weeks and thereafter 6, 12 and 24 months. Anteroposterior and lateral X rays were taken to determine union and if any residual deformity was present. Patients were evaluated using the demerit point system of Gartland and Werley 5 and Sarmiento modification of Lindstrom criteria. 6 The range of motion used for comparison are standardized. 7 An informed consent was taken from all the patients and approval of Ethics and Scientific Committee of Department of Orthopedics. medial fragments. Hence, a total of 10 mm of subchondral support is achieved with the help of two pegs and two screws [Figure 1]. Operative procedure The patients were operated under supraclavicular brachial plexus block, intra venous regional anesthesia or general anesthesia. First an external fixator was used to mark its placement with skin impression and then applied with one 2.5 mm Schanz pin in the radius about 10 cm proximal to the fracture and another Schanz pin in the base of the second metacarpal laterally with forearm in supination. The external fixator was distracted to achieve radial length and attain preliminary reduction/distraction of the fracture. A volar approach was used with an incision over the tendon of flexor carpi radialis. The fracture site was opened through tendon sheath. The pronator quadratus, was erased from the radius beginning laterally and retracted ulnar wards. Fracture reduction was achieved. Distraction/ compression was adjusted according to the requirement. Metaphyseal comminution in some cases necessitated bone grafting. Cancellous bone graft was harvested from the upper end of the tibia. The jig was placed over the distal radius and two drill holes with 2.7 mm drill bit were Implant description The implant used was the volar spade plate with two volar pegs [A.K Surgicals, Pune, India]. The plate is 1.5 mm thick made of stainless steel 316 L. Length of the plate is 50 mm and it is 28 mm broad distally. There are two square pegs fused to the plate distally in an inert atmosphere of argon. Each peg is 2.5 mm broad, 2.5 mm thick and 16 mm in length. These pegs provide support under the scaphoid and lunate fossae. The pegs do not penetrate the opposite cortex to prevent extensor tendon irritation or rupture. Additional holes are present at either corner of the plate in line with the pegs, 2.5 mm screws can be placed through these holes to hold the lateral and Figure 1: Photograph of two peg volar spade plate with its measurements 537 Indian Journal of Orthopaedics September 2015 Vol. 49 Issue 5

3 made only in the volar cortex to receive the two pegs. These holes should be as distally as possible to provide optimal subchondral support. Jig was then removed, and plate was hammered in and checked under image. Out of the two distal screws, one was directed in the radial styloid and another in the postero medial cortex of the radius. The other proximal screws were placed simultaneously. On confirming adequate stability after fixation of the plate, the fixator was removed. Postoperative protocol 0 2 weeks Movements of the fingers, elbow and shoulder were encouraged in the first 2 weeks. Elevation of the forearm was maintained during the first 2 days to avoid edema. 2 4 weeks In extraarticular fractures, wrist (dorsiflexion and palmarflexion), finger (flexion and extension) and forearm (pronation and supination) mobilization were started. In type C fractures (intraarticular), where the comminution was significant, a below elbow splint was used for 2 3 weeks. Results The average age was years (range years). Twenty six were males and 14 females. They were all closed fracture and were classified according to AO/ASIF system, including type A2 (n = 4), type A3 (n = 10), type C1 (n = 8), type C2 (n = 8) and type C3 (n = 10) [Figure 2A]. Right side was fractures in 18 cases and left side in 22 cases. Postoperative average movements [Table 1] [Figure 2B] and radiological outcome in terms of loss of palmar tilt, radial shortening and loss of radial deviation was measured according to Sarmiento modification of Lindstrom criteria at final followup [Tables 2 and 3]. According to the Gartland and Werley demerit point system excellent results were seen in 25% (n = 10), good results in 60% (n = 24), fair in 15% (n = 6) and poor in none (n = 0). We also found out that type A fractures showed excellent to good results and 15% of fair results were seen in type C fractures [Tables 4 and 5]. Two patients presented with wrist stiffness (5%) with a fair outcome and one with reflex sympathetic dystrophy (2.5%). After 4 weeks Range of motion exercises was continued with gradually progressive use of the wrist being permitted. Followup record was maintained at 2, 4, 6 and 8 weeks and thereafter 6, 12 and 24 months. Discussion In our study, 50% of the cases were of OTA type C that is, complete articular fractures. According to Knirk and Jupiter, 3 these fractures must always be separated from extra articular Statistical analysis The descriptive analysis consisted of frequency and percentage for discrete data and meant for continuous data. In cases where pre and postoperative assessment was not available P value was not calculated but descriptive statistics has been provided for comparison with other studies in the literature. a b Figure 2A: (a) X-ray distal forearm with wrist joint anteroposterior and lateral views showing AO type C3 fracture distal end radius (b) Postoperative x-rays anteroposterior and lateral views showing peg spade plate in situ Figure 2B: Clinical photograph of same patient with complete range of motion of wrist at final followup Indian Journal of Orthopaedics September 2015 Vol. 49 Issue 5 538

4 Table 1: Mean average range of motion at last followup Values Dorsiflexion Palmarflexion Radial deviation Ulnar deviation Pronation Supination Average Normal fractures as their response to treatment and the functional outcomes are always quite distinct. Thielke et al. [8] used fixed angle plates and von Recum et al. [9] used 2.4 and 3.5 mm LCP for fixation of these fractures. Extra articular comminuted fractures (type A2 and A3) are inherently prone to re displacement after closed reduction. Hence, they have been included in the study. Other indications were osteoporosis, comminution where maintenance of radial length was required, fractures with late presentation as well as malunited extra articular fractures. The volar approach has been used for fixation of the distal radius fracture in our series. In a series of study by Herron et al. found that dorsal plate placement can lead to extensor tendon irritation, tenosynovitis or tendon rupture and limitation of wrist movements. 10 Hence plate removals are required more often. 10 Advantage of dorsal plate position is that it gives access to the place of the main lesion since the displacement is usually dorsal. However, volar plate position has the advantages of better soft tissue cover, flat surface for easy plate fixation, better tension band effect, leaving dorsal soft tissue intact and avoiding bone graft leakage. 11 Furthermore, removal of the volar plate is not absolutely essential. 12 This has been documented and supported by the studies done by Drobetz and Kutscha Lissberg. 13 Ligamentotaxis with an external fixator has been used. However, the fixator has to be retained for 6 8 weeks. Hence, there is a risk of developing wrist and finger stiffness. Also, ligamentotaxis is not a reliable method to restore radio palmar tilt. We used external fixator in all the patients for ligamentotaxis and fracture reduction, which was removed immediately after plate fixation for early mobilization. This helps in restoring the radial length whereas the tilt is controlled by the internal fixation. Hence, external fixation is combined with internal fixation. 14 In order to provide angular stability and to avoid loss of reduction or collapse Drobetz and Kutscha Lissberg introduced the locked screw plates into use. 13 These plates have matching threads on the screw head and the hole to provide angular stability. However, the plates developed had three 3.5 mm locking screws in the distal row for fixation. These screws and plates are very bulky for the structurally smaller bones. At the same time, plates with four or five fixed angle tines have been developed. These plates function like a blade plate, lessening the role of metaphyseal screws and provide Table 2: Sarmiento modification of Lindstrom criteria Grades Loss of palmar tilt ( ) Radial shortening (mm) Loss of radial deviation ( ) Excellent 0 <3 5 Good Fair Poor At least 15 At least 12 >14 Table 3: Result based on Sarmiento modification of Lindstrom criteria Grades Loss of palmar tilt ( ) Radial shortening (mm) Loss of radial deviation ( ) Excellent (%) 2 (5) 35 (87.5) 37 (92.5) Good (%) 38 (95) 5 (12.5) 3 (7.5) Fair Poor Values are the number of patients in each criteria with percentage in brackets Table 4: Demerit point system of Gartland and Werley Residual deformity Range 0-3 points Prominent ulnar styloid 1 Residual dorsal tilt 2 Radial deviation of hand 2-3 Subjective evaluation Range 0-6 points Excellent - No pain, disability or limitation of 0 movements Good - Occasional pain, limitation of motion, 2 no disability Fair- Occasional pain, some limitation of 4 motion, weakness in wrist, no disability if careful, activities slightly restricted Poor - Pain, limitation of motion, disability, 6 activities more or less markedly restricted Objective evaluation Range 0-5 points Loss of dorsiflexion 5 Loss of ulnar deviation 3 Loss of supination 2 Loss of palmar flexion 1 Loss of radial deviation 1 Loss of circumduction 1 Pain in DRUJ 1 Grip strength 60% or less than opposite side 1 DRUJ=Distal radioulnar joint rigid fixation allowing early motion. 15 But putting in four or five tined plate was technically more difficult and hence the plates are out of favour. 16 The two peg volar spade plate which we developed is based on the same principle of angular stability. The two pegs are inserted under the sub chondral bone of the distal radius and support the articular fragments. It is technically easier to place two fixed pegs than to place four tines. Additional 539 Indian Journal of Orthopaedics September 2015 Vol. 49 Issue 5

5 Table 5: Results based on demerit point system of Gartland and Werley Patient number/ Grade Points Type A/C (n) Present series Thielke et al. fixed angle von Recum et al. 2.4 mm/3.5 mm LCP Number of patients Excellent /04 25% 35% 62% 43% Good /16 60% 50% 34% 41% Fair /06 15% 15% 4% 16% Poor >21 0/0 0% 0% LCP=Locked compression plates sub chondral support is achieved by placing two screws, one on either side of the pegs one in the radial styloid and another in the postero medial cortex of radius. Thus, we achieved a total of 10 mm of sub chondral support (using 2.5 mm two screws and two pegs). Moreover, the 2.5 mm construct of the plate is structurally homologous to the Indian radius morphology. Drobetz and Kutscha Lissberg 13 used a forearm splint for 2 weeks postoperatively in type C fractures after fixation with a locked screw plate. In type C fractures with osteoporosis or type C3 fractures with pronounced articular involvement and small fragments, they used the immobilization for 4 weeks. Orbay and Fernandez 15 also used a wrist splint for 3 weeks post operatively after fixation with a volar fixed angled plate. In our study, we used a forearm and wrist brace post operatively for 1 week for extra articular fractures and 2 weeks for intraarticular fractures followed by intermittent usage for the same period later to allow physiotherapy. Thielke et al. 8 used a volar fixed angle plate. Wrist motion was restored to 80% of normal. Orbay and Fernandez 15 on reviewing retrospectively their results of treatment with a volar fixed angle plate reported achieving 58 dorsiflexion, 55 volarflexion, 80 pronation and 76 supination. Our results were comparable. Radiologically Thielke et al. 8 reported a loss of 1 volar tilt, 1 ulnar tilt and radial shortening of 1 mm. Orbay and Fernandez 15 achieved a final volar tilt of 6, ulnar tilt 20 and had a final radial shortening of <1 mm. Our radiological results according to Sarmiento modification of Lindstrom criteria were as mentioned in Table 3. Thielke et al. 8 treated 49 displaced articular fractures with the overall outcome on Gartland and Werley scales being 85% excellent to good scores. Similarly, Recum et al. 9 showed 96% and 86% excellent to good in 2.4 mm and 3.5 mm LCP respectively. We had comparable results of 85% in excellent to good category [Table 5]. We also noticed that patients presented with significant osteoporosis at an early age, which is common in Indian population 17 and also a study by Meiners et al. 18 discussed a newer concept of using an angular stable plates with good results in 90% osteoporotic fractures. 18 The limitations of this study include the absence of a control group and also that it is a retrospective study. To conclude the two peg volar spade plate provides a stable sub chondral support and maintenance of corrective length in osteoporotic, metaphyseal comminuted, comminuted intraarticular and malunited fractures of the distal radius. Early mobilization with this implant helps in restoring wrist motion and prevents development of wrist stiffness. References 1. Colles A. On the fracture of the carpal extremity of the radius. Clin Orthop Relat Res 2006;445: Aro HT, Koivunen T. Minor axial shortening of the radius affects outcome of Colles fracture treatment. J Hand Surg Am 1991;16: Knirk JL, Jupiter JB. Intraarticular fractures of the distal end of the radius in young adults. J Bone Joint Surg Am 1986;68: Taleisnik J, Watson HK. Midcarpal instability caused by malunited fractures of the distal radius. J Hand Surg Am 1984;9: Gartland JJ Jr, Werley CW. Evaluation of healed Colles fractures. J Bone Joint Surg Am 1951;33 A: Sarmiento A, Pratt GW, Berry NC, Sinclair WF. Colles fractures. Functional bracing in supination. J Bone Joint Surg Am 1975;57: Hoppenfeld, S. Physical Examination of the Spine and Extremities. Appleton Century Crofts, a publishing division of Prentice Hall, New York, NY; Thielke KH, Wagner T, Bartsch S, Echtermeyer V. Angularly stable radius plate: Progress in treatment of problematic distal radius fracture? Chirurg 2003;74: Von Recum J, Matschke S, Jupiter JB, Ring D, Souer JS, Huber M, et al. Characteristics of two different locking compression plates in the volar fixation of complex articular distal radius fractures. Bone Joint Res 2012;1: Herron M, Faraj A, Craigen MA. Dorsal plating for displaced intraarticular fractures of the distal radius. Injury 2003;34: Arora R, Lutz M, Hennerbichler A, Krappinger D, Espen D, Gabl M. Complications following internal fixation of unstable distal radius fracture with a palmar locking plate. J Orthop Trauma 2007;21: Woon CYL, Lee JYL, Ng SW, Teoh LC. Late rupture of flexor pollicis longus tendon after volar distal radius plating: a case report and review of the literature. Injury (Extra) 2007;38: Drobetz H, Kutscha Lissberg E. Osteosynthesis of distal radial fractures with a volar locking screw plate system. Int Orthop 2003;27: Anderson JT, Lucas GL, Buhr BR. Complications of treating Indian Journal of Orthopaedics September 2015 Vol. 49 Issue 5 540

6 distal radius fractures with external fixation: A community experience. Iowa Orthop J 2004;24: Orbay JL, Fernandez DL. Volar fixed angle plate fixation for unstable distal radius fractures in the elderly patient. J Hand Surg Am 2004;29: Sobky K, Baldini T, Thomas K, Bach J, Williams A, Wolf JM. Biomechanical comparison of different volar fracture fixation plates for distal radius fractures. Hand (N Y) 2008;3: Acharya S, Srivastava A, Sen IB. Osteoporosis in Indian women aged years. Arch Osteoporos 2010;5: Meiners J, Jürgens C, Mägerlein S, Wallstabe S, Kienast B, Faschingbauer M. Osteoporotic fractures of the distal radius. What is new?. Chirurg 2012;83: How to cite this article: Hardikar SM, Prakash S, Hardikar MS, Kumar R. Two peg spade plate for distal radius fractures A novel technique. Indian J Orthop 2015;49: Source of Support: Nil, Conflict of Interest: None. 541 Indian Journal of Orthopaedics September 2015 Vol. 49 Issue 5