Use of the extensor retinaculum as a donor site for bone-ligament-bone grafts

The recent introduction of bone-ligament-bone grafts for ligament reconstruction in hand surgery has led to a search for suitable graft donor sites. The extensor retinaculum had been suggested, but harvesting details were still lacking. We therefore studied the anatomy of the extensor retinaculum, with radiography and morphometric measurements. Ten cadaver wrists were dissected; the thick portion of the retinaculum and its insertions on the radius in the different extensor compartments were studied. The compartments were wire-marked, and AP radiographs taken of each specimen. The retinaculum spanning the first three compartments was removed with the bony ridges it inserted on, and the inter-ridge retinaculum length was measured. A comparison of our dissections with the radiographs showed that only the radial compartments 1, 2 and 3 had constant bony insertions on both ridges, making them suitable for bone-ligament-bone grafting. The mean compartment length was 11.7 mm (compartment 1), 17 mm (compartment 2) and 7.3 mm (compartment 3) respectively. Thus, the extensor retinaculum can be relied upon to provide bone-ligament-bone grafts from the first three compartments, for possible use in ligament reconstructions in the hand and wrist.