Fig. 1. (A) Photograph of a disarticulated and skinned mouse hindlimb secured to cork for fixation and architectural analysis. Bones are pinned with 30 gauge needles and the foot is secured to a cork footplate that aligns the tarsal and metatarsal bones. In this example, we attempted to fix the limb in 90° of knee flexion and 90° of ankle flexion. TA, tibialis anterior. (B) Lateral radiograph of hindlimb shown in A. Ankle and knee joint angles were as defined as in Materials and methods (shown as dotted lines) and were measured as 89.4° (knee) and 92.4° (ankle).