Talocalcaneal luxation in dogs was studied by anatomic dissection of the talocalcaneal joint in cadavers and review of five clinical cases. The integrity of the talocalcaneal joint was maintained by two strong ligaments traversing the tarsal sinus between the two bones. The joint was found to be a low motion joint. Luxation in clinical cases was not always apparent on standard radiographic views. Three dogs were treated surgically with a screw inserted in lag fashion from talus to calcaneus. One luxation was treated surgically with figure-of-eight orthopedic wires and one was treated with external coaptation. Four dogs returned to their previous levels of function without clinically detectable lameness.

Forty canine hock joints were used to study the anatomy and function of the medial and lateral tarsocrural collateral ligament complexes. Dissection of the ligaments was used to describe the anatomic arrangement, and location and tenseness in various positions. The component parts of the ligament complexes were evaluated for their contribution to stability of the tarsocrural joint. The medial and lateral tarsocrural collateral ligament complexes were composed of several components. The medial tibiotalar and lateral calcaneofibular short component parts were important static joint stabilizers in both flexion and extension. The long medial and lateral ligaments and the medial tibiocentral short component were less important in maintaining joint stability in flexion but were important in extension. The stability of the joint as a whole did not depend on any individual ligament component, but rather all components of the ligament complex, including the joint capsule and malleoli, acted together to stabilize the joint.

A technique for replacement of the medial and lateral collateral ligaments of the tarsocrural joint in dogs was developed based on studies of normal anatomy and function. The medial or lateral tarsocrural joint was made unstable by removal of the respective malleolus, ligaments, and joint capsule; the component parts of the collateral ligaments were replaced using suture material to function as ligament prostheses. The technique was found to be effective in maintaining near normal joint motion and adequate joint stability in cadavers immediately following surgery, and in dogs observed for up to 39 months postoperatively. No degenerative joint disease was noted upon gross or radiographic examination.

An anatomic analysis of retrograde and normograde intramedullary (IM) pinning of proximal, midshaft, and distal femoral fractures was performed in 28 canine cadavers. For all fracture locations, normograde pins were significantly more cranial in the middle gluteal muscle than retrograde pins (p less than 0.01). There was no significant difference between pinning techniques in craniocaudal position of the IM pin in the superficial gluteal muscle. In distal fractures, normograde pins were placed significantly more lateral than retrograde pins in the superficial gluteal muscle (p less than 0.01). One of 15 normograde pins and 9 of 13 retrograde pins were located in the medial half of the trochanteric fossa. Normograde pins were significantly more lateral in the trochanteric fossa than were retrograde pins in midshaft fractures (p less than 0.01). Normograde pins were significantly (p less than 0.01) farther from the sciatic nerve than retrograde pins when the hip was positioned at coxofemoral flexion angles of 85 degrees in midshaft and 110 degrees in distal fractures. Seven of 13 retrograde pins, but none of 15 normograde pins, contacted the sciatic nerve. Normograde pinning of the femur may be less likely to induce sciatic nerve injury, particularly in midshaft and distal fractures.