Surgical management of Osteochondral Lesions of the Talus

Abstract

Osteochondral lesions of the talar dome (OLTs) are being recognized with increasing frequency, in part because of heightened understanding and awareness, and in part because of improved MRI and arthroscopic technology. Considerable controversy surrounds the etiology and natural history of OLTs. OLTs are not similar, they are variable in dimensions , location (medial or lateral) , containment and the type of lesion (chondral, subchondral, cystic). OLT clinical features are not specific and surgeon need high index of suspicion to diagnose it. Patients most commonly present with persistent ankle pain after an ankle sprain . While some patients present with intermittent deep ankle pain during or after activity without history of trauma OLT is a radiologic diagnosis. However, there is no evidence to support a gold standard for imaging with respect to the diagnosis of OLT .Radiography remains the first choice as it is easy and inexpensive. Then, CT and/or MRI are always necessary. CT is superior in showing the subchondral character of the lesions and the integrity of subchondral cortical plate. MRI is superior in assessing articular cartilage non-invasively and the stability of oseochondral fragment, besides, it is the only imaging to detect BME. Evaluation using a combination of CT and MRI is the best in giving all details about the lesion. A nonoperative approach is used to treat all lesions initially; unless there is displaced fragment. Surgical treatment of OLTs present a challenge and remains controversial. There are many surgical techniques reported in the management of OLTs, the most reported are marrow stimulation, OATS and ACI. Practically, not all techniques are available for every surgeon. Moreover, there is a lack of sufficient evidence to support the surgeon `s choice for the best technique for each lesion. The purpose of this study was to assess the short term results of drilling and autologous cancellous bone graft sealed with periosteal patch in management of all types and sizes of osteochondral lesion talus and to analyze the results to investigate the significant prognostic factors. Twenty ankles in twenty patients were enrolled in this prospective case series study between 2012-2014 . The patients were 12 males and 8 females with mean age of 34 , all of them had a documented focal OLT on MRI and failure of conservative treatment. The Outcomes were measured using the American Orthopedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale, Berndt and Harty scale, and Saxena criteria. Fifteen patients were treated with arthroscopic drilling, one of which underwent Brostorm repair for ankle instability, while the other five patients were treated with bone graft sealed with periosteal patch. The AOFAS score significantly improved from a mean of 71.78 ± 11.38 (range, 51-87) preoperatively to 89.17 ± 9.66 (range, 67-100) postoperatively (P value < 0.01). According to the Saxena criteria ,this study results were excellent in 9 (44.4%), good in 7 (33.3%) , fair in 3 (16.7%) , and poor in1 (5.6% ) .The Berndt and Harty scale results were good in 14 (70% ), fair in 4 (20% ), and poor in 2 patients (10%) Statistical analyses showed a prognostic significance for lesion containment ; uncontained lesions had a significantly higher incidence of poor outcomes than contained lesions (P < .05). In older patients (>37 years), there was a statistically insignficant trend toward inferior clinical outcomes .There was no association between clinical outcome and gender, history of trauma or lesion location. There was no complications In conclusion , drilling and autologous cancellous bone graft sealed with periosteal patch are effective and safe in surgical management of OLTs. Lesion containment is an important prognostic factor.