Will OAT work for a severe ankle injury for a post-menopausal woman?

Q: After suffering a severe ankle injury, I discovered that I have a hole in the ankle bone that extends through the cartilage to the bone itself. My surgeon has recommended something called an OAT procedure. At 55 years old and being a post-menopausal woman, will this work for me? I don’t heal as quickly as I once did.

A: The holes, also known as “defects” in the cartilage that extend down to the bone, can be addressed with a procedure called osteochondral autograft transfer (OAT). This technique involves taking a plug of healthy cartilage and bone from a non-weight-bearing area (usually from the knee) and transplanting it into the damaged area of the joint. The term “autograft” indicates that the tissue used in the procedure comes from the patient’s own body.

A recent study conducted in Korea explored the outcomes of this procedure on the talus, the ankle bone, by conducting a second arthroscopic examination a year later. Such second-look arthroscopic exams are rare, making the findings of this study particularly valuable. Instead of relying on MRI, the researchers used arthroscopy to get a detailed view of the quality of the bone and cartilage graft.

By analyzing a range of patient variables, the researchers identified the key factors influencing the success of the procedure. They examined the impact of age, gender, body mass index (BMI), duration of symptoms, severity (including depth and size) and location of the lesion, as well as the presence of bone cysts, as predictors of outcomes. They also assessed the results based on patient satisfaction, pain, function, and activity level.

The study found that 95% of the participants reported good to excellent outcomes. Interestingly, age was not a statistically significant factor in the success of the procedure. The most critical factor was related to the surgical technique itself. For the OAT procedure to be successful, the surgeon must restore the joint surface smoothly, evenly, and with anatomical precision.

It is crucial to avoid impingement (pinching) of the surrounding soft tissues. The graft’s shape and size should closely match the defect, and the graft must be carefully covered with a patch to prevent any areas from being left exposed. If gaps or uncovered spots are present, they tend to fill in with fibrous cartilage, which can result in an unstable defect area.

The authors of this study recommend conducting longer-term studies (beyond one year) to assess any changes and identify factors that might not be apparent within the first 12 months. They also noted that the study had a relatively small sample size (52 ankles), suggesting that the results should be confirmed with a larger group before being considered definitive.

However, this study does provide some evidence that your age and postmenopausal status may not significantly impact the success of the procedure. It’s important to discuss these concerns with your surgeon before proceeding with the surgery. Reparative surgery is crucial in such cases to prevent the development of premature arthritis, which can lead to a chronically painful and unstable ankle.

Reference: Yong Sang Kim, MD, et al. Factors Associated with the Clinical Outcomes of the Osteochondral Autograft Transfer System in Osteochondral Lesions of the Talus. Second-Look Arthroscopic Evaluation. In The American Journal of Sports Medicine. December 2012. Vol. 40. No. 12. Pp. 2709-2719.