SLR - November 2012 - N. Jake Summers(2)
Reference: Kim Y.S., Park E.H., Lee H.J., Koh Y.G., Lee J.W. Clinical Comparison of the Osteochondral Autograft Transfer System and Subchondral Drilling in Osteochondral Defects of the First Metatarsal Head. The American Journal of Sports Medicine. 2012; 40: 1824
Scientific Literature Review
Reviewed by: N. Jake Summers, DPM
Residency Program: Mount Auburn Hospital, Harvard Medical School, Cambridge, MA
Podiatric Relevance:
Osteochondral defects (OCDs) can be seen on many articular surfaces in the foot and ankle and are common on the first metatarsal head. These lesions can be painful and can progress to severe osteoarthritis of the first MTPJ. As with other OCDs, lesions on the first metatarsal head can be challenging and can be treated in a variety of ways. Two common methods of treatment are subchondral drilling or microfracture and the Osteochondaral Autograft Transfer system (OATS).
Methods:
A retrospective comparison of 22 consecutive patients (24 feet) treated surgically for osteochondral defects of the first metatarsal head was performed. Group A (14 feet) was treated via subchondral drilling and Group B (10 feet) was treated with the OATS method. Mean follow-up was 25.1 months. A Visual Analog Scale (VAS) and American Orthopaedic Foot and Ankle Society (AOFAS) hallux metatarsophalangeal-interphalangeal scale were utilized. The Roles and Maudsley score was used to evaluate patient satisfaction. The Tegner Activity Scale and Activity Rating Scale (ARS) were both utilized to determine activity levels. MRI films were evaluated in a blinded manner by an independent radiologist to evaluate lesions and lesion size, which were then compared with intraoperative measurements and findings.
Results:
Subchondral drilling was performed using a 0.9 mm Kirschner wire, and donor plugs for the OATS procedure were harvested from the lateral edge of the lateral trochlea. Both groups showed improvement of the VAS score without significant difference between the two. Both groups had improvement in the AOFAS score with Group B having significantly greater improvement. Good to excellent results were obtained in 35 percent of Group A and in 90 percent Group B. Activity levels improved for both groups, with Group B showing a higher statistically significant improvement in activity level. Also of significance was the data shown for larger lesions greater than 50 sware mm, the outcomes were significantly worse than for smaller lesions in group A, but no significant difference was found in the outcomes of group B based on lesion size.
Conclusions:
The results of this study suggest that the OATS procedure is a viable treatment option for OCD lesions of the first metatarsal head when compared to subchondral drilling. Limitations of this study include its retrospective nature, the small sample size, concern for bias especially with procedure and patient selection and comparability of the two study groups, variation in follow-up duration and poorly defined secondary outcome measures. Both procedures may improve function and decrease pain associated with OCDs of the first metatarsal head. And size of the OCD defect appears to be an important clinical factor, especially for lesions larger than 50 square mm. Further studies would be more revealing about the advantages and disadvantages of each procedure and their long-term outcomes and well-conducted randomized trials are needed to further account for both measured and unmeasured confounders.