SLR - April 2011 - Vikram Thakar
Reference: Hee Jin Park, MD, Seung Doh Cha, MD,* Hyung Soo Kim, MD,* Soo Tae Chung, MD,* Noh Hyuck Park, MD, Jeong Hyun Yoo, MD,* Jai Hyung Park, MD,* Joo Hak Kim, MD,* Tae Woo Lee, MD,* Chang Hyun Lee, MD,* and Se Man Oh, MD* Reliability of MRI Findings of Peroneal Tendinopathy in Patients with Lateral Chronic Ankle Instability, Clin Orthop Surg. 2010 December; 2(4): 237–243.
Scientific Literature Review
Reviewed by: Vikram Thakar, DPM
Residency Program: Massachusetts General Hospital, Boston MA
Podiatric Relevance:
The peroneus longus and peroneus brevis tendons are responsible for inversion and plantarflexion of the ankle. Acute tears and dislocation of these tendons are often observed in young athletes, where as tenosynovitis and partial tears are caused mostly by repetitive mechanical stress rather than isolated injury. Most patients with chronic lateral ankle instability and a partial longitudinal tear of the peroneus brevis tendon have a history of repetitive ankle sprains or inversion trauma.
Methods:
Patients included in this study had visited a hospital due to ankle sprains and discomfort of more than 6 months duration, between March 2006 and November 2009. Eight-two (82) patients underwent lateral ankle surgical reconstruction under the diagnosis of chronic lateral ankle instability based on the preoperative MRI findings. The study group included 47 males and 35 females, with an average age of 36.4 years. A total of eight-two (82) ankles were examined (50 right and 32 left). Patients with rheumatic diseases were excluded.
Results:
Based on the surgical findings of the total 82 cases, the MRI findings were true positive, false positive, true negative, and false negative in 26, 13, 38, and 5 cases, respectively. The MRI sensitivity and specificity were 83.9%, and 74.5%, with positive predictive value, negative predictive value, and accuracy rate of 66.7%, 88.4%, and 78.0%, respectively. Of the 39 MRI-identified peroneal lesions, 14 were partial peroneal tendon tears, 15 were peroneal tenosynovitis, 3 were peroneal tendon dislocations, 17 were low-lying muscle belly, and 6 were peroneus quartus. Of the 31 peroneal lesions identified during surgery, partial peroneal tendon tear, peroneal tenosynovitis, peroneal tendon dislocation, low-lying muscle belly, and peroneus quartus were noted in 11, 4, 5, 12, and 1 cases, respectively. The MRI sensitivity, specificity, positive predictive value, negative predictive value, and accuracy rate for detection of a partial tear were 54.5%, 88.7%, 42.9%, 92.6%, and 84.1%, and for detection of peroneal tenosynovitis were 25%, 95.5%, 6.7%, 82.1%, and 79.3%, respectively.
Conclusions:
In conclusion, MRI is a useful diagnostic modality for detecting peroneal tendinopathy in patients with chronic lateral ankle instability. However, the positive predictive value, accuracy rate, and inter-observer reliability of MRI findings were found to be relatively low in this study. Therefore, thorough physical examinations and careful observation should also be performed in combination with MRI scanning to ascertain a definitive diagnosis of peroneal tendinopathy.