Pancarpal / Pantarsal Arthrodesis

Arthrodesis is a salvage procedure — it is recommended when the joint cannot be preserved and function cannot be restored by other means. Common indications include:

• Severe hyperextension injury (e.g., falling from a height — a common cat injury) where ligaments are ruptured and the joint collapses
• End-stage arthritis with bone-on-bone contact that is no longer responsive to medical management
• Pancarpal or pantarsal fractures that are not amenable to conventional repair
• Chronic instability from nerve damage or severe soft-tissue loss

Fusion eliminates the range of motion at that joint, but dogs and cats compensate remarkably well — the limb remains functional and load-bearing, and many patients return to comfortable trotting and playing.

Arthrodesis is performed under general anesthesia. Key steps include:

• The joint cartilage is completely removed from all opposing bone surfaces within the joint to expose raw, vascular cancellous bone — a necessary step for fusion to occur
• The joint is positioned at a functional angle (typically 10–15 degrees of extension for the carpus, matched to the patient's normal standing posture)
• A contoured bone plate and screws rigidly fix the bones in this position; cancellous bone graft (taken from within the same bone or a nearby site) is packed into the joint space to accelerate fusion
• In some configurations, additional screws or intramedullary pins supplement the plate

Over the following weeks, new bone bridges the former joint space. Once fusion is complete, the construct is essentially as strong as solid bone.

Pre-operative X-rays, and in some cases CT imaging, characterize the extent of joint damage, the quality of the surrounding bone, and any concurrent injuries in the limb. Bloodwork is performed to assess anesthetic risk. If an infection is present (such as a septic joint), it is managed before elective fusion. For hyperextension injuries with open wounds, contamination must be controlled prior to implant placement. Owners should fast the pet from food the evening before surgery and prepare a quiet, confined recovery space at home. The team will review any medications — anti-inflammatories are typically paused before surgery.

Bone fusion takes time, and protecting the repair during that period is critical to a successful outcome. The recovery typically proceeds as follows:

• Weeks 1–4: a supportive bandage or splint is maintained over the repair; strict rest and leash-only activity; pain management; bandage changes at the hospital
• Weeks 4–8: bandage may be discontinued as soft tissue swelling resolves; continued leash restriction; follow-up X-rays to assess early bone bridging
• Weeks 8–12: repeat X-rays confirm progressive fusion; controlled activity increases; implants are intentionally left in place until fusion is complete
• 3–4 months: for most patients, fusion is radiographically confirmed and full activity can gradually resume

Weight management significantly reduces plate stress and speeds bony union — keeping the pet lean during recovery is strongly encouraged.

Arthrodesis is a major orthopedic procedure, and the main risks include delayed or failed fusion (non-union), implant failure before fusion occurs, infection, and wound complications — particularly in cases involving traumatic injury or poor initial tissue quality. Failure to follow activity restrictions is a significant risk factor for implant failure. The permanent loss of motion at the fused joint is expected and does not generally impair walking, light trotting, or normal daily activity, though very high-speed running or jumping may show a subtle gait change. Most owners report dramatic improvement in their pet's comfort after complete fusion — the elimination of instability and bone-on-bone pain is transformative.