34th Annual Scientific Meeting proceedings

Objectives:

Autologous mosaicplasty technique is a surgical procedure which has the advantage of restoring the injured weight-bearing articular surface and the adjacent subchondral bone by implantation of multiple cylindrical osteochondral grafts. The purpose of this study was to summarise and evaluate the outcome of horses treated using this technique.

Methods:

Thirty-three horses were admitted for mosaic arthroplasty. Age of the animals ranged from 1 to 15 years and all of them were lame with a median grade of 3 out of 5. Twenty-three horses had a lesion in the medial or lateral femoral condyle and 10 had a subchondral cystic lesion in the distal third metacarpal or metatarsal bone. Osteochondral autografts harvested from the contralateral or ipsilateral medial femoral trochlea were implanted in 31 cases and allografts were applied in 2 horses. The follow-up period was a minimum of 12 months.

Results:

Sixty-four percent of horses became sound and were able to compete at previous or higher level than before surgery. Twenty-four percent improved and 12% showed lack of improvement or deterioration of lameness postoperatively. Postoperative complications occurred in 6 horses. No significant association was found between outcome and preoperative lameness score, age, or number of implanted grafts. An association was found between coexistent joint pathology and outcome (p=0.026).

Conclusions:

Mosaic arthroplasty resulted in improvement in 88% of the operated horses with 64% competing at higher level than before the surgery. This surgical procedure can be safely and effectively used to treat subchondral bone cysts and focal full-thickness articular cartilage defects, however careful case selection is essential.