Hemipelvic and proximal femoral limb salvage endoprosthesis with tendon ongrowth in a dog

Vet Surg. 2018 Sep 21. [Epub ahead of print]

OBJECTIVE: To report the clinical application of a hemipelvic and proximal femoral endoprosthesis for limb salvage.

STUDY DESIGN: Retrospective case report.

ANIMAL: One 5-year-old, neutered female, flat coated retriever with a malignant neoplasia of the left coxofemoral joint.

METHODS: An invasive soft tissue mass (histiocytic sarcoma) with bone lysis of the femoral head and acetabulum was noted on radiographs, computed tomography (CT), and MRI. Custom-designed hemipelvic and proximal femoral endoprostheses were produced from CT images and manufactured with hydroxyapatite coated surfaces to allow tissue integration. The proximal femoral implant allowed tendon ongrowth and muscle attachment. The pelvic implant was anchored to the ilium and ischium with screws, and the femoral implant was cemented. Chemotherapy consisted of lomustine (CCNU).

RESULTS: No evidence of implant loosening or local/thoracic metastases was noted on radiographs or CT at 6 weeks and at 3, 6, 9, and 12 months after surgery. A neurapraxia resolved 14 weeks postoperatively. Intensive rehabilitation was performed. At 12 months, activity was unrestricted with minimal residual lameness. The dog was euthanized at 14 months for metastatic disease.

CONCLUSION: Limb salvage with a hemipelvic and proximal femoral endoprosthesis resulted in limb function and survival for 14 months.

CLINICAL SIGNIFICANCE: Neoplasia involving the bones of the coxofemoral joint traditionally requires hemipelvic resection and pelvic limb amputation. This report provides evidence that limb salvage can result in satisfactory levels of activity.