Use of dorsal buttress plate fixation for ulnar carpometacarpal joint fracture dislocations for early mobilization: outcomes of 11 cases.

<bold>Aim: </bold>This study reviews the surgical outcomes of using dorsal buttress plate for open reduction and internal fixation of ulnar (5th, or 4th and 5th) CMCJ fracture subluxation or dislocations.<bold>Methods: </bold>A retrospective review of 11 patients at our center who underwent operative fixation with dorsal buttress plating technique was performed. The surgery was performed between February 2012 and March 2017. Outcome measurements include radiographic evaluation of time to union, grip strength, and range of motion of the wrist.<bold>Results: </bold>Of 11 patients in our case series, eight had injuries involving both 4th and 5th CMCJs, while three had isolated involvement of 5th CMCJ. Mean time to union on radiographs was 48 days (IQR 17.0; range 30-88). The median palmar flexion and dorsiflexion of the wrist were 56° (IQR 11.3; range 50°-80°) and 65° (IQR 10.0; range 60°-80°) respectively. Patients regained a median of 79% of grip strength (IQR: 36.0, range 43-100). All fingers achieved full range of motion, and no patient had scissoring of the fingers. Two patients had temporary mild numbness over the dorsoulnar aspect of the hand in the region of the 4th webspace. Five patients underwent removal of implants due to plate breakage (n = 2), or mild pain or pain with cold (n = 3). All patients were well after plate removal, and all the patients with pain had resolution of pain after implant removal.<bold>Conclusion: </bold>The dorsal buttress plate is a viable option for fixation of ulnar CMCJ fracture dislocations to allow early mobilization. [ABSTRACT FROM AUTHOR]