Motec® total wrist arthroplasty surgical procedure: personal pearls and pitfalls

Personal pearls and pitfalls are described, as well as an enhanced surgical procedure for performing Motec® prosthesis surgery on the wrist. While the objective of the procedure is to correctly position the implants, a standardized and meticulous surgical technique is crucial for achieving favourable results and avoiding complications, given the significant learning curve associated with this prosthesis. The most important tip for the carpo-metacarpal side is to ensure that the capitate is sufficiently freed through a 'shoe box' osteotomy, so that it is aligned with the third metacarpal in all planes. It is also important to ensure that the definitive metacarpal screw extends beyond the endomedullary isthmus of the third metacarpal. On the radial side, the radial screw must be positioned correctly, aligned with the radius medullary canal, and not tilted. The short neck must never be used. A new test has been proposed to prevent the joint from being overly constrained. This test is positive (pathological) when wrist flexion and hand supination occur during radial deviation. Finally, one of the most important steps is to check for a cam effect in every extreme position. Failure to eliminate cam effects can cause persistent pain and contribute to implant loosening over time. Cadaver lab practice is advised prior to the first implementation, or an experienced surgeon should be present, to minimize potential complications. LEVEL OF EVIDENCE: Therapeutic Level 5.