Original Research

Unstable Dorsal Proximal Interphalangeal Joint Fracture-Dislocations Treated With Extension-Block Pinning

Am J Orthop. 2015 March;44(3):122-126

Unstable proximal interphalangeal (PIP) joint fracture-dislocations, which can cause significant disability, can be treated with multiple techniques. Extension-block pinning (EBP) allows for early motion and is less technically demanding than alternative surgical treatments.

In the study reported here, 12 patients with unstable dorsal PIP fracture-dislocations were treated with closed reduction of the PIP joint followed by percutaneous insertion of a Kirschner wire (K-wire) into the distal aspect of the proximal phalanx.

For these patients, extent of articular surface involvement averaged 43% (range, 25%-75%). Active motion was initiated early after surgery, and the K-wire was removed a mean of 25 days after pinning. Radiographic reduction of joint dislocation was achieved and maintained for 11 of the 12 patients at a mean follow-up of 35.5 months. At follow-up, mean visual analog scale (VAS) score was 0.64 (scale, 0-10). Mean score on the Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) questionnaire was 5.7, suggesting minimal functional impairment. Mean PIP active motion was 84° (range, 50°-110°). Grip strength was equal between operative and contralateral hands. Patient satisfaction most closely correlated with low VAS and QuickDASH scores. One patient developed a malunion, which was treated with corrective osteotomy.

EBP is a simple, safe, and reproducible technique for unstable PIP fracture-dislocations. This technique yields outcomes similar to those reported for more complex surgical procedures.

PDF Download

References

1. Leibovic SJ, Bowers WH. Anatomy of the proximal interphalangeal joint. Hand Clin. 1994;10(2):169-178.

2. Kiefhaber TR, Stern PJ. Fracture dislocations of the proximal interphalangeal joint. J Hand Surg Am. 1998;23(3):368-380.

3. Ng CY, Oliver CW. Fractures of the proximal interphalangeal joints of the fingers. J Bone Joint Surg Br. 2009;91(6):705-712.

4. Isani A. Small joint injuries requiring surgical treatment. Orthop Clin North Am. 1986;17(3):407-419.

5. McElfresh EC, Dobyns JH, O’Brien ET. Management of fracture-dislocation of the proximal interphalangeal joints by extension-block splinting. J Bone Joint Surg Am. 1972;54(8):1705-1711.

6. Hastings H 2nd, Carroll C 4th. Treatment of closed articular fractures of the metacarpophalangeal and proximal interphalangeal joints. Hand Clin. 1988;4(3):503-527.

7. O’Rourke SK, Gaur S, Barton NJ. Long-term outcome of articular fractures of the phalanges: an eleven year follow up. J Hand Surg Br. 1989;14(2):183-193.

8. Grant I, Berger AC, Tham SK. Internal fixation of unstable fracture dislocations of the proximal interphalangeal joint. J Hand Surg Br. 2005;30(5):492-498.

9. Hamilton SC, Stern PJ, Fassler PR, Kiefhaber TR. Mini-screw fixation for the treatment of proximal interphalangeal joint dorsal fracture-dislocations. J Hand Surg Am. 2006;31(8):1349-1354.

10. Lee JY, Teoh LC. Dorsal fracture dislocations of the proximal interphalangeal joint treated by open reduction and interfragmentary screw fixation: indications, approaches and results. J Hand Surg Br. 2006;31(2):138-146.

11. Inoue G, Tamura Y. Treatment of fracture-dislocation of the proximal interphalangeal joint using extension-block Kirschner wire. Ann Chir Main Memb Super. 1991;10(6):564-568.

12. Sugawa I, Otani K, Kobayashi A. Treatment of fracture dislocation PIP-joint by Kirschner wire extension block method. Cent Jpn J Orthop Traumat. 1979;22:1409-1412.

13. Vitale MA, White NJ, Strauch RJ. A percutaneous technique to treat unstable dorsal fracture-dislocations of the proximal interphalangeal joint. J Hand Surg Am. 2011;36(9):1453-1459.

14. Badia A, Riano F, Ravikoff J, Khouri R, Gonzalez-Hernandez E, Orbay JL. Dynamic intradigital external fixation for proximal interphalangeal joint fracture dislocations. J Hand Surg Am. 2005;30(1):154-160.

15. Ellis SJ, Cheng R, Prokopis P, et al. Treatment of proximal interphalangeal dorsal fracture-dislocation injuries with dynamic external fixation: a pins and rubber band system. J Hand Surg Am. 2007;32(8):1242-1250.

16. Morgan JP, Gordon DA, Klug MS, Perry PE, Barre PS. Dynamic digital traction for unstable comminuted intra-articular fracture-dislocations of the proximal interphalangeal joint. J Hand Surg Am. 1995;20(4):565-573.

17. Ruland RT, Hogan CJ, Cannon DL, Slade JF. Use of dynamic distraction external fixation for unstable fracture-dislocations of the proximal interphalangeal joint. J Hand Surg Am. 2008;33(1):19-25.

18. Dionysian E, Eaton RG. The long-term outcome of volar plate arthroplasty of the proximal interphalangeal joint. J Hand Surg Am. 2000;25(3):429-437.

19. Durham-Smith G, McCarten GM. Volar plate arthroplasty for closed proximal interphalangeal joint injuries. J Hand Surg Br. 1992;17(4):422-428.

20. Calfee RP, Kiefhaber TR, Sommerkamp TG, Stern PJ. Hemi-hamate arthroplasty provides functional reconstruction of acute and chronic proximal interphalangeal fracture-dislocations. J Hand Surg Am. 2009;34(7):1232-1241.

21. Williams RM, Kiefhaber TR, Sommerkamp TG, Stern PJ. Treatment of unstable dorsal proximal interphalangeal fracture/dislocations using a hemi-hamate autograft. J Hand Surg Am. 2003;28(5):856-865.

22. Viegas SF. Extension block pinning for proximal interphalangeal joint fracture dislocations: preliminary report of a new technique. J Hand Surg Am. 1992;17(5):896-901.

23. Hume MC, Gellman H, McKellop H, Brumfield RH Jr. Functional range of motion of the joints of the hand. J Hand Surg Am. 1990;15(2):240-243.

24. Salter RB. The physiologic basis of continuous passive motion for articular cartilage healing and regeneration. Hand Clin. 1994;10(2):211-220.

25. Newington DP, Davis TR, Barton NJ. The treatment of dorsal fracture-dislocation of the proximal interphalangeal joint by closed reduction and Kirschner wire fixation: a 16-year follow up. J Hand Surg Br. 2001;26(6):537-540.

26. Aladin A, Davis TR. Dorsal fracture-dislocation of the proximal interphalangeal joint: a comparative study of percutaneous Kirschner wire fixation versus open reduction and internal fixation. J Hand Surg Br. 2005;30(2):120-128.

27. Waris E, Alanen V. Percutaneous, intramedullary fracture reduction and extension block pinning for dorsal proximal interphalangeal fracture-dislocations. J Hand Surg Am. 2010;35(12):2046-2052.

28. Bain GI, Mehta JA, Heptinstall RJ, Bria M. Dynamic external fixation for injuries of the proximal interphalangeal joint. J Bone Joint Surg Br. 1998;80(6):1014-1019.

29. Eaton RG, Malerich MM. Volar plate arthroplasty of the proximal interphalangeal joint: a review of ten years’ experience. J Hand Surg Am. 1980;5(3):260-268.

30. Green A, Smith J, Redding M, Akelman E. Acute open reduction and rigid internal fixation of proximal interphalangeal joint fracture dislocation. J Hand Surg Am. 1992;17(3):512-517.

31. Inanami H, Ninomiya S, Okutsu I, Tarui T. Dynamic external finger fixator for fracture dislocation of the proximal interphalangeal joint. J Hand Surg Am. 1993;18(1):160-164.

32. Suzuki Y, Matsunaga T, Sato S, Yokoi T. The pins and rubbers traction system for treatment of comminuted intraarticular fractures and fracture-dislocations in the hand. J Hand Surg Br. 1994;19(1):98-107.

33. Weiss AP. Cerclage fixation for fracture dislocation of the proximal interphalangeal joint. Clin Orthop. 1996;(327):21-28.

34. Agee JM. Unstable fracture dislocations of the proximal interphalangeal joint. Treatment with the force couple splint. Clin Orthop. 1987;(214):101-112.

The proximal interphalangeal (PIP) joint plays a crucial role in hand function, accounting for an estimated 85% of the motion required to grasp an object.¹ The anatomy and biomechanics of the PIP joint, however, make it particularly prone to injury.^2,3 Dorsal PIP fracture-dislocations represent a subset of PIP injuries that often require surgical intervention.² The stability of these fracture-dislocations largely depends on the extent of articular involvement of the base of the middle phalanx. Fractures that involve less than 30% of the joint surface typically remain stable after reduction.^2,4,5 In cases in which involvement ranges from 30% to 50%, PIP joint stability is more tenuous, and more joint flexion is required to maintain concentric reduction. Fractures that involve more than 50% of the articular surface are unstable and require operative intervention.^2,5,6 Fractures that require more than 30° of flexion for reduction maintenance are generally considered unstable and may benefit from surgical intervention.²

The goals of treatment for this injury are to restore a stable, concentrically reduced joint and initiate early joint mobilization to prevent stiffness, pain, recurrent instability, and posttraumatic arthritis.^3,7 Numerous surgical interventions for unstable PIP fracture-dislocations have been proposed, including open reduction and internal fixation (ORIF),^8-10 extension-block pinning (EBP),^11-13 dynamic external fixation,^14-17 volar plate arthroplasty,^18,19and hemi-hamate resurfacing arthroplasty.^20,21 Many of these techniques can be technically demanding and may require prolonged immobilization. EBP can be performed easily and efficiently and allows for early joint motion.

Extension-block pinning—placing a Kirschner wire (K-wire) into the head of the proximal phalanx at an angle that blocks PIP extension and prevents joint subluxation—was first described by Sugawa and colleagues¹² in 1979. In a study by Inoue and Tamura,¹¹ patients treated with EBP had a mean PIP range of motion (ROM) of 94° at a mean follow-up of 14 months. In a series of 3 case reports, Viegas²² noted an inverse relationship between extent of articular surface involvement and postoperative ROM in patients treated with EBP.

We conducted a study to expand on previous research on pain, function, and satisfaction outcomes in addition to ROM. We hypothesized that percutaneous EBP is an effective treatment for unstable dorsal PIP fracture-dislocations and has efficacy similar to that of more complex and technically demanding methods of treatment.

Materials and Methods

We retrospectively reviewed patient charts to identify candidates for this study. Inclusion criteria were unstable dorsal PIP fracture-dislocations treated with EBP and minimum 4-month follow-up. (Fracture-dislocations were deemed unstable if they involved at least 30% of the articular surface or required more than 30° of flexion for reduction maintenance.) Exclusion criteria were open injury, neurovascular or tendon injury, or any prior injury to the PIP joint.

Twelve patients (5 females, 7 males) treated over a 4-year period (2002–2006) met the inclusion criteria. Mean age was 30 years (range, 15-64 years). Each surgery was performed by Dr. Hagberg or Dr. Balk. Half the cases involved the dominant hand. Two small fingers, 4 ring fingers, 2 long fingers, and 4 index fingers were injured. The injuries were sustained in an all-terrain vehicle accident (n = 1), in falls (n = 2), while swimming (n = 1), or while playing softball (n = 3), football (n = 4), or soccer (n = 1). Mean time from injury to surgery was 7.5 days (range, 4-27 days). Extent of articular surface involvement of the base of the fractured middle phalanx was calculated using preoperatively obtained lateral radiographs.

Surgical intervention was performed in a reproducible fashion. All patients were treated with closed reduction of the PIP joint under fluoroscopic guidance. Before pinning, joint stability was assessed fluoroscopically both at rest and through an arc of motion. A single smooth 0.045-in K-wire was then inserted percutaneously into the distal and dorsal aspects of the proximal phalanx in retrograde fashion (Figure 1). During wire insertion, the distal interphalangeal joint was flexed to relax the intrinsic mechanism, and the central slip tendon was pierced just proximal to its insertion. We have not noted significant adhesion formation about the central slip with this technique, likely because of limited tendon excursion in this location. Stable joint reduction was confirmed with fluoroscopy. No attempt was made to reduce the intra-articular fracture at the base of the middle phalanx.

A therapy program was initiated 2 to 9 days after surgery. At the first postoperative visit, patients were allowed to perform active ROM (AROM) with the pin in place (Figure 1). K-wires were removed a mean of 25 days (range, 17-31 days) after surgery. A static dorsal block splint was then applied, and patients were encouraged to remove it several times per day for AROM between 20° and full flexion until 6 weeks after surgery. At that time, formal occupational therapy was commenced for another 6 weeks. If there was residual flexion contracture of the PIP joint, dynamic extension splinting was initiated after fracture consolidation.