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Cranial transposition of the fibular head stabilizes the stifle joint by displacing the distal attachment of the lateral collateral ligament (LCL). The forces applied to the LCL after displacement may cause ligamentous elongation. This investigation evaluated the morphological, histological, and biomechanical changes of the LCL after fibular head transposition (FHT) in dogs. Unilateral cranial cruciate ligament (CCL) excision and FHT were performed on 25 dogs. Cross-sectional area, length, histological, and structural properties of the LCL were evaluated 3 weeks, 4 months, and 10 months after surgery. Ligament length means were significantly increased at week 3, month 4, and month 10 compared with intraoperative length means. No significant changes in elongation were observed after week 3. Fibrovascular proliferation within the LCL increased the cross-sectional area and associated structural properties.

The suspensory apparatus of one forelimb was surgically disrupted in six adult horses by transecting the distal sesamoidean ligaments. A double-braided prosthetic ligament made of aramid yarn was installed to support the flexor surface of the metacarpophalangeal joint. The prosthesis was routed through tunnels in the third metacarpal bone and proximal phalanx, and secured to bone with screws. Evaluation by radiography, synovial fluid analysis, cinematography, and dynamography was performed before surgery and at weeks 16 and 30. Supracondylar cortical lysis and periosteal proliferation were observed on postoperative radiographs. Synovitis and fragmentation of the prosthesis were apparent from synovial fluid evaluation. Weight bearing and metacarpophalangeal joint motion were decreased and loading was transferred in part to the opposite forelimb. Clinical lameness improved and weight bearing increased during the second half of the 30-week period. At necropsy, there was abrasion of the prosthesis and the articular surfaces in contact with the prosthesis. Diffuse granulomatous synovitis developed in response to aramid fiber fragments within the synovium.

Four cases of canine granular cell tumour (myoblastoma) were diagnosed at the Washington Animal Disease Diagnostic Laboratory between 1977 and 1981. Two of the tumours occurred in the tongue, one in the lip and one in the larynx. Three cell types were found in the tumours. Granular cells, with abundant periodic acid-Schiff (PAS)-positive cytoplasmic granules, were most numerous. Interstitial cells resembled fibroblasts and were often adjacent to collagen fibrils. Angulate body cells contained PAS-positive, ovoid cytoplasmic inclusions composed of microtubular subunits. Review of these and reported cases indicates no breed or sex predisposition for this rare tumour. The tongue is the most common site and all but one tumour have occurred in or adjacent to the oral cavity. There have been no reports of recurrence or metastasis of granular cell tumours except the recurrence of a disputed case in the subcutis of a dog.

The Cloward technique for intervertebral fusion was utilized on 12 horses ranging from 3 months to 2 years of age. Of the 12 horses, 9 had been diagnosed as having equine cervical vertebral malformation (CVM) or “wobbles,” and 3 were normal controls. A large hole was drilled from the ventral border of the vertebral bodies spanning the intervertebral disc and the vertebral end plates of the 2 articulating vertebrae. Frozen homologous bone dowels of slightly larger diameter from equine cadaver ilia were inserted in the holes. No adverse postoperative complication arose. Clinical improvement was seen in all horses with CVM. Three months postoperatively, partial or complete fusion was evident radiographically in 11 of the 12 horses. Necropsies were performed 3–6 months postoperatively to evaluate the quality of the fusion. Cadaver manipulation demonstrated reduced intervertebral movement at the operative site in all cases. The articulations of the equine cervical spine can be operatively fused by the Cloward technique, and surgically induced trauma is minimal. This technique can be used for stabilizing subluxations and may be applicable for treating fractures and osteolytic processes that have weakened vertebrae.