SLR - November 2015 - Adam Nowland

Comparison of Arthroscopic Microfracture for Osteochondral Lesions of the Talus With and Without Subchondral Cyst

Reference: Lee KB, Park HW, Cho HJ, Seon JK. Comparison of Arthroscopic Microfracture for Osteochondral Lesions of the Talus With and Without Subchondral Cyst. Am J Sports Med. 2015 Aug;43(8):1951-6

Scientific Literature Review

Reviewed By:
Adam Nowland, DPM
Residency: Hoboken University Medical Center

Podiatric Relevance:  As arthroscopy becomes more prevalent and a more sought after form of treatment by both doctors and patients alike, many treatment options become available. With larger osteochondral lesions of the talus (OLT) having a more defined manner of treatment, this paper seeks to explore the option of microfracture as a primary treatment of lesions with an underlying subchondral cyst. As of today, only few articles have reported good outcomes with only microfracture treatment, but many are limited in the fact they were implemented in a retrospective manner. The authors of this paper seek to compare the clinical outcomes of patients treated only via microfracture drilling with subchondral cysts vs. without subchondral cysts.

This prospective cohort study identified 130 ankles with an osteochondral lesion of the talus between 2005 and 2010. The inclusion criteria was having unilateral symptomatic OLT, a single focal lesion, a lesion smaller than 2.0 cm, age ranging from 18-60 years old, failed nonoperative treatment, and maintaining a minimum two year follow up. Twenty-five patients did not meet the inclusion criteria and were excluded from the authors study and three patients did not meet the two year follow up rate. Of the remaining 102 patients, two groups were formed dividing cystic lesions (n = 45) and non-cystic lesions (n = 57).  The authors used the AOFAS ankle-hindfoot scale, visual analog scale (VAS), and Ankle Activity Score (AAS) to evaluate pain preoperatively and postoperatively. Pre-operatively the lesions were identified using x-ray and MRI. Surgically microfracture awls were used to place holes in a systematic spiral pattern roughly 3-4 mm apart, 4-5 mm deep, and peripheral to the center of the lesion. Postoperatively patients were splinted in neutral position for one week and transitioned to weight bearing as tolerated in walking boot for second week. Full weight bearing was allowed after the two week period.

Results: No significant difference in pain outcomes were shown between the two groups showing that microfracture can be utilized to treat cystic lesions in the same capacity as it is used without cystic lesions. AOFAS scores in both groups were noted to improve significantly at the two year mark, rising from 64.8 in cystic group and 66.2 in non-cystic group to 91.8 and 91.3 respectively. The mean VAS score was 7.5 in cyst group and 7.3 in non-cyst group and improved to 2.3 and 2.2 respectively. The mean AAS score was noted to improve from 2.7 in cyst and 2.6 in non-cyst group to 6.7 and 6.5 respectively. Radiologic improvement was shown in both x-ray and MRI findings by comparing pre-op vs post-op lesions using Berndt-Hardy (x-ray) and Anderson (MRI) classifications.

Arthroscopic microfracture is a low cost, minimally invasive treatment used for lesions that are symptomatic to the patient and are found to be smaller than 1.5cm. The results of this study show that microfracture provides adequate pain relief in patients that have a small osteochondral lesion of the talus. The authors of this paper concluded that arthroscopic microfracture could be a primary treatment for small to midsized OLT regardless of the presence of an underlying cyst. My conclusion, after reading this article, is that using an arthroscopic microfracture approach to treating small OLT may provide my future patients with an outcome that has been shown to provide adequate pain relief in the long term. This information proves useful to myself and to my peers in guiding treatment decisions as well as being able to have explored a treatment that may have been looked over in the past.

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