CASE:A 77-year-old woman who sustained a distal radius and ulna fracture underwent open reduction internal fixation through a standard flexor carpi radialis (FCR) approach. On dissection, a proximal division of the median nerve was identified, with an aberrant motor branch crossing radial to ulnar deep to FCR and superficial to flexor pollicis longus. CONCLUSION:Although many anatomic variants of the median nerve have been described, the current case demonstrates a particularly important median motor branch variant, imposing a substantial risk of iatrogenic injury during a standard FCR approach.

Objective:To compare the exposure of the coronoid process, anteromedial facet, and anterior band of the medial collateral ligament using the flexor carpi ulnaris (FCU)-splitting approach with the Taylor-Scham approach modified with an ulnar nerve transposition.Methods:Thirty approaches were performed on 15 fresh cadavers using a randomized cross-over design and standardized incision. Access to key anatomic landmarks was assessed, and a calibrated digital image was taken from the surgeon's best perspective of each approach. Images were analyzed using ImageJ (National Institutes of Health) software to calculate the area of osseous exposure.Results:All key anatomic landmarks were visualized using both approaches. The average area of exposure for the Taylor-Scham was 19.5 cm(2) compared with 13.6 cm(2) for the FCU-splitting (P < 0.0001). The distal extent of the FCU-splitting approach is limited by the ulnar nerve and its branches to the humeral head of the FCU.Conclusion:The Taylor-Scham approach provides a more extensile exposure of the anteromedial coronoid and proximal ulna than the FCU-splitting approach while avoiding cross-tensioning of the ulnar nerve.

BACKGROUND:Intramedullary implants are an increasingly common method for fixation of metacarpal fractures. Numerous techniques for instrumentation have been described with varied consideration for the risk of extensor tendon injury. The current cadaveric study evaluates the prevalence and degree of extensor tendon injury and compares percutaneous approaches with different drilling techniques. METHODS:Ninety-six metacarpals (thumbs excluded) from 24 fresh-frozen cadaveric upper extremities were used to compare 2 percutaneous approaches and 2 drilling techniques. This resulted in 4 subgroups available for comparison: oscillate to bone (OB), forward to bone (FB), oscillating through the skin (OS), and forward through the skin (FS). After instrumentation, the extensor tendons were dissected and disruption was characterized. The main outcome measures were tendon "hit rate" and relative extensor tendon defect width. RESULTS:Tendon hit rate was significantly higher in the long finger (LF), that is, 79.2%, compared with other metacarpals: index finger, 20.8%; ring finger, 12.5%; and small finger 25%. The mean relative tendon disruption was significantly less in the OB group (16.05%) compared with the other groups: FB (31.84%), FS (31.50%), and OS (29.85%). CONCLUSION:Retrograde intramedullary screw fixation of metacarpal fractures can be performed using percutaneous approaches without a significant disruption of the extensor mechanism. Instrumentation through a longitudinal stab incision down to the metacarpal head and the use of drill oscillation minimize injury to the extensor tendons. The LF extensor tendon is most at risk with retrograde intramedullary implant placement.