CLINICAL AND ELECTROPHYSIOLOGICAL FINDINGS AND FOLLOW-UP IN TARSAL TUNNEL-SYNDROME

The authors report clinical and electrophysiological findings in 59 pa tients with tarsal tunnel syndrome FS) and follow-up in 23 of them. Th e entrapment was prevalent in females; was bilateral in 6 patients and involved medial planter in 7 and lateral plantar nerves in two cases. Eleven presented with other nerve entrapment syndromes or focal monon europathies, due to hereditary neuropathy with liability to pressure p alsy or systemic diseases. The other 48 subjects had TTS without any o ther related entrapment syndromes: 23 were idiopathic cases, 13 had a history of local trauma, 3 had systemic diseases and the others had ex ternal or intrinsic compressions. The most frequent symptoms were para esthesia or dysaesthesia (86% of feet) and pain (55%). Hypoaesthesia o f the sole and weakness of toe flexion were evident in 74% and 22% of feet, respectively. Absence of sensory action potential or slowing of sensory conduction velocity (SCV) of the plantar nerves were present i n 77% of feet; significant differences of SCV between affected and una ffected plantar nerves and/or between distal sural and plantar nerves were evident in 14%. Abnormalities of plantar SCV were therefore absen t in only 9% of feet. Distal motor latency was delayed in 55% and elec tromyography showed neurogenic changes in 45% of sole muscles. Five ca ses (6 feet) underwent surgery with excellent or good results in 5, 4 of them also showing improvement in distal conduction of the plantar n erves. Nine were treated with local steroid injections, with good resu lts shown in 6 patients. Nine other patients who did not receive any t herapy showed a disappearance of symptoms or good outcome in 6 cases. The subjects with poor therapeutic results had SI radiculopathy or sys temic diseases. The authors underline that patients with connective ti ssue diseases should not be treated by surgical decompression because they may have subclinical neuropathy. Some subjects with idiopathic or trauma-induced TTS recover spontaneously. Surgical release should be limited to cases with space-occupying lesions and when conservative tr eatments fail. (C) 1998 Elsevier Science ireland Ltd. All rights reser ved.