Abstract
Aims
The primary aim of this study was to determine the long-term survival of OATS (Osteochondral Autograft Transfer System) (Arthrex, Florida, USA) grafting in our centre and evaluate the reasons for failure, the secondary aim was to ascertain if age, gender, BMI, site or size of OATS graft had any influence on outcome.
Methods
Details of patients undergoing an OATS procedure from 1999 to 2008 were collected. Loosening, graft degeneration or subsequent surgery in the form of arthroplasty, revision OATS¯ or any other osteochondral procedure was considered as failure. Oxford knee score and UCLA activity score evaluated outcome.
Results
57 patients were included in our study with a mean follow up of 5.9 years (range 0.5 to 10.5). Kaplan Meier analysis demonstrated 92% survival at 8 years (95% CI 0.79 to 0.96). Two of the four failures occurred in patients with varus mal-alignment. Using linear regression analysis we found the size and site of the graft had no influence but noted an improved outcome in patients with a younger age and lower BMI for both UCLA activity score and Oxford knee score.
Conclusion
We consider OATS¯ to be a reliable method of treatment in the long-term for contained articular cartilage lesions up to 4 cm□. Nevertheless, careful attention should be paid to the mechanical axis prior to grafting.
