Knee Joint Distraction in a Dog as Treatment for Severe Osteoarthritis

Osteoarthritis (OA) is the most common joint disease diagnosed in veterinary practice. There is no cure; where conservative treatment fails, a joint prosthesis is the last resort. In human OA patients, temporary distraction is a joint-preserving treatment which provides clinical and structural benefits, and postpones the need for total knee replacement for up to 9 years. In this single case, feasibility of knee joint distraction (KJD) was assessed in a 9-year-old female Dobermann with severe OA. Osteoarthritis of the left stifle joint was diagnosed clinically and radiographically. Knee joint distraction was applied for 7 weeks using a custom-made, hinged, external fixator. Follow-up of 1 year included owner questionnaires, orthopaedic examination, radiography, and force plate analysis. Additionally, synovial fluid biomarkers were assessed. Application and removal of the KJD frame were successfully accomplished without surgical complications. During KJD, the dog tolerated the frame well and maintained the use of the left hindlimb. Mild pin tract infection developed during the distraction period, which responded well to oral antibiotic medications. Owners reported clinical improvement during KJD and the follow-up period. This was confirmed by force plate analysis, demonstrating improvement from 3 months and onward. KJD proved to be a feasible strategy to treat end-stage OA in this single case; clinical efficacy remains to be determined in a larger cohort.