Carpometacarpal subluxation and dislocation following first metacarpal distraction osteogenesis

A 4-year-old boy (Case 1) with history of amniotic band syndrome and a 50-year-old man with history of traumatic amputation to right thumb (Case 2) both underwent thumb lengthening procedures with metacarpal osteotomy with distraction osteogenesis. Post operatively, both were noted to have CMC joint instability with volar dislocation in Case 1 and dorsal subluxation in Case 2, which were treated with observation and CMC arthroplasty, respectively. Complications after thumb metacarpal lengthening have been well described throughout literature. Here we present the only reports of CMC subluxation or dislocation following first metacarpal distraction osteogenesis. Clinicians should be aware of this rare but associated complication in patients undergoing this procedure.