Distal Tendinosis of the Tibialis Anterior Tendon

Abstract

Disorders of the tibialis anterior (TA) tendon have infrequently been reported but spontaneous rupture of this tendon is well recognized. The clinical presentation of tendinosis without rupture of the distal TA has not previously been reported and is the basis of this paper. A study of 29 patients diagnosed with distal TA tendinosis was undertaken. Data collected included, patient demographics, weight, height, pain profile and examination findings. All patients underwent MRI of the symptomatic foot. Operative findings of those patients undergoing surgery for this condition were collected. Twenty-nine patients (32 feet) were included in the study group. Their mean age was 62 years and 27 patients were female. Twenty-one patients were overweight. The usual presenting symptom was burning medial midfoot pain that was often reported to be worst at night. Swelling over the TA tendon was frequently observed. On MRI the TA was thickened in all patients. Longitudinal split tears were observed in 19 feet. Chondral thinning and/or osteophyte formation at the first tarsometatarsal or medial naviculocuneiform joints was observed in 11 feet. Eleven feet underwent surgery. Universally the TA tendon was macroscopically thickened and had lost its normal fibrillary appearance. Longitudinal split tears were observed in eight tendons. Pathology was typical of a degenerative tendinosis. Distal TA tendinosis is a condition that seems to predominantly affect overweight elderly women. It often presents with nocturnal burning medial midfoot pain.