Trapezo-metacarpal arthroplasty by rotation transfer of the trapezo-metacarpal joint. Anatomical study and operative technique

Abstract

To correct trapezium dysplasia we propose a new surgical technique. The operation consists of a double osteotomy of the trapezium and of the first metacarpal base, thereby harvesting the trapezo-metacarpal joint en-bloc. Vascularization is via the radial artery pedicle divided at the first web level. The articular block is then rotated 180 degrees on the longitudinal axis of the thumb. An anatomic study was performed on six fresh cadaveric upper limbs. The radial artery was injected with colored latex, 5 cm above the wrist. The peri-articular vascular network was studied. The feasibility of harvesting and rotating the articular bloc after double osteotomy of the first metacarpal basis and the trapezium was also studied. In all the cases, the radial artery was present with branches supplying the peri-articular vascular network. After double osteotomy of the metacarpal base and of the trapezium, the articular bloc was harvested and rotated by 180 degrees. We describe the surgical technique. The surgical technique has been confirmed with the first clinical cases. The double oblique osteotomy with rotation of the articular bloc corrects trapezium dysplasia and preserves first metacarpal abduction. This procedure appears to be a solution in cases of trapezium dysplasia associated with instability and early stage osteoarthritis.