Scaphoid Dislocation: A Rare Pattern of Wrist Instability - A Case Report

Introduction

Scaphoid dislocations are rare injuries, usually resulting from high-energy trauma and therefore associated to other lesions which may obscure the diagnosis.

Case Presentation

The authors present a case of a 59-year-old man with a partial complex dislocation of the scaphoid, diagnosed 6 days after the initial injury. Closed reduction was unsuccessfully attempted, so the patient was submitted to open reduction and internal fixation. The functional and radiological results were good.

Conclusion

Physicians should be aware of this rare lesion, because a delayed diagnosis may rend the treatment more difficult and compromise the results. The threshold for an open treatment should be low because rotatory subluxations of the scaphoid may not be detectable in simple radiographs and be responsible for the appearance of degenerative changes in the long term.

Reduction and Association of the Lunotriquetral Ligament for Reverse Perilunate Dislocation

Background  Reverse perilunate injuries are rare. Contrary to perilunate injuries, the violent force would start from the lunotriquetral ligament, go reversely toward the radial side, and cause the reverse or ulnar-sided perilunate dislocation. Case Description  We describe a 31-year-old man with a reverse perilunate dislocation, who presented to our institution 3 weeks after a motorcycle accident. The patient was successfully treated with the reduction and association of the lunate and triquetrum (RALT) procedure by using closed maneuver and percutaneous headless compression screw fixation. The patient can obtain a good radiographic result and satisfactory function at the 30-month follow-up. Literature Review  Many case series were reported concerning the perilunate injuries. However, few cases of reverse perilunate dislocation have been reported in the literature. No cases of reverse perilunate dislocation treated 3 weeks after the injury with the RALT procedure have been reported. Clinical Relevance  In this case, we found that the dislocation could still be reduced with the closed maneuver. With the RALT procedure, the carpal alignment can be maintained and the stability can be regained. Also, the functional outcomes are good.

Comparison of outcomes between axial radial and axial ulnar carpal injuries

Axial carpal injuries are rare entities where a traumatic force transmits through the intermetacarpal space, dissociating the carpometacarpal joint and disrupting the distal carpal row in an axial radial or axial ulnar pattern via true axial force or compressive crush mechanism. Differences in outcomes remain unclear with regard to the specific type of axial carpal injury pattern. A retrospective case series identified 37 wrists (in 37 patients) over 25 years who presented to a Level 1 trauma centre, with 20 wrists experiencing an axial radial injury and 17 wrists experiencing an axial ulnar injury. Of all the variables evaluated, only axial radial injuries were identified as predictors of poor outcome as defined by Mayo Wrist scores with univariate analysis demonstrating 6 times increased risk and multivariate analysis demonstrating 15 times increased risk of a poor outcome compared with axial ulnar injuries. This knowledge will provide prognostic information to surgeons managing patients with these severe injuries.

LEVEL OF EVIDENCE

IV.

Perilunate dislocations treated with external fixation and percutaneous pinning

Background The purpose of this study was to review clinical and radiographic outcomes of perilunate dislocations (PLDs) and fracture-dislocations (PLFDs) treated with external fixation and Kirschner wires (K-wires). Materials and Methods Twenty patients (18 males and 2 females) with a mean age of 38 years (range 18-59) with an acute PLD or PLFD were treated with external fixator and K-wires. There were 12 PLDs and seven transscaphoid and one transstyloid PLFDs. The median time from trauma to operation was 8 hours (range 2-12 hours). Indirect reduction via ligamentotaxis was achieved in 17 patients with a mean age of 38years (range 18-59). There were 12 PLDs and 5 trans-scaphoid PLFDs; however, in three cases (two transscaphoid and one transstyloid PLFDs), indirect reduction failed and an open reduction was required. The intercarpal ligaments were not repaired even after open reduction. Results The mean follow-up was 39 months (range 18-68 months). The flexion-extension range of motion (ROM) and grip strength of the injured wrist averaged 80% and 88%, respectively, of the corresponding values for the contralateral wrists. According to Cooney's scoring system, overall functional outcomes of the 17 patients were rated as excellent in 4 patients, good in 8, fair in 4, and poor in 1. Fifteen patients returned to their former occupations. Two patients with a trans-scaphoid perilunate injury developed nonunion of the scaphoid, and two developed posttraumatic arthritis. Conclusion External fixation plus percutaneous K-wires for the treatment of acute PLDs has satisfactory midterm functional and radiographic outcomes. When successful, this minimally invasive technique is simple and provides restoration of the carpal alignment. It may especially be useful in the polytrauma patient, thanks to its decreased operative time and diminished blood loss, when other emergent surgical procedures may be necessary. An open reduction with possible fixation may be necessary for PLDs and PLFDs, especially in the presence of polytrauma and scaphoid comminution.

LEVEL OF EVIDENCE

IV.