Searching for hidden, painful osteochondral lesions of the ankle in patients with chronic lower limb pain - two case reports -.

It is easy to overlook osteochondral lesions (OCLs) of the ankle in patients with chronic lower limb pain, such as complex regional pain syndrome (CRPS) or thromboangiitis obliterans (TAO, Buerger's disease). A 57-year-old woman diagnosed with type 1 CRPS, and a 58-year-old man, diagnosed with TAO, complained of tactile and cold allodynia in their lower legs. After neurolytic lumbar sympathethic ganglion block and titration of medications for neuropathic pain, each subject could walk without the aid of crutches. However, they both complained of constant pain on the left ankle during walking. Focal tenderness was noted; subsequent imaging studies revealed OCLs of her talus and his distal tibia, respectively. Immediately after percutaneous osteoplasties, the patients could walk without ankle pain. It is important to consider the presence of a hidden OCL in chronic pain patients that develop weight-bearing pain and complain of localized tenderness on the ankle.