Distance mapping in three-dimensional virtual surgical planning in hand, wrist and forearm surgery: a tool to avoid mistakes.

PURPOSE Three-dimensional planning in corrective surgeries in the hand and wrist has become popular throughout the last 20 years. Imaging technologies and software have improved since their first description in the late 1980s. New imaging technologies, such as distance mapping (DM), improve the safety of virtual surgical planning (VSP) and help to avoid mistakes. We describe the effective use of DM in two representative and frequently performed surgical interventions (radius malunion and scaphoid pseudoarthrosis). METHODS We simulated surgical intervention in both cases using DM. Joint spaces were quantitatively and qualitatively displayed in a colour-coded fashion, which allowed the estimation of cartilage thickness and joint space congruency. These parameters are presented in the virtual surgical planning pre- and postoperatively as well as in the actual situation in our cases. RESULTS DM had a high impact on the VSP, especially in radius corrective osteotomy, where we changed the surgical plan due to the visualization of the planned postoperative situation. The actual postoperative situation was also documented using DM, which allowed for comparison of the VSP and the achieved postoperative situation. Both patients were successfully treated, and bone healing and clinical improvement were achieved. CONCLUSION The use of colour-coded static or dynamic distance mapping is useful for virtual surgical planning of corrective osteotomies of the hand, wrist and forearm. It also allows confirmation of the correct patient treatment and assessment of the follow-up radiological documentation

Extension osteotomy of the metacarpal I and ligamentoplasty of the trapeziometacarpal joint for the treatment of early-stage osteoarthritis and instability of the trapeziometacarpal joint.

Osteoarthritis (OA) is a common disease of the first carpo-metacarpal (CMC I) joint. Biomechanical factors promoting OA are the shape of the CMC I-joint, being a biconcave-convex saddle joint with high mobility and the increased instability caused by joint space narrowing, ligamentous laxity, and direction of force transmission of the abductor pollicis longus (APL) tendon during adduction. The closing wedge osteotomy of the base of the first metacarpal is joint preserving treatment option. We combine this closing wedge osteotomy with a ligamentoplasty to stabilize the joint. In this manuscript, we provide a detailed description of the indication, discuss biomechanical aspects and the surgical technique in detail