Ultrasound Case Study
Tibialis anterior rupture
Rob Mast, Extended Scope Physiotherapist and MSK Sonographer
This patient in their 60’s presented to me in clinic with an approximate 3 month history of a sudden onset of dorsal foot pain. The patient was limping but had not taken much notice of this. In the past month the dorsal foot pain had subsided and instead they had noticed a cramping sensation in the peroneal muscle region.
Examination showed that the foot was kept in a position of eversion, see images. This was also seen during gait where it appeared hard to clear the floor with the medial foot. Clinical observation demonstrated a significant compensatory gait pattern with excessive recruitment of the peroneal musculature. Local palpation over the peroneal muscles demonstrated tightness and discomfort consistent with pain due to chronic muscle spasm. Palpation revealed pain over the insertion of tibialis anterior.
The peroneal tendons and musculotendinous junction appeared intact on ultrasound. Ultrasound of the tibialis anterior tendon showed a retracted rupture of this tendon with the defect overlying the anterior recess of the talocrural joint. The tendon was absent in a transverse view. The ultrasound findings correlated well with the appearance of a tibialis anterior rupture.as described by Varghese & Bianchi in their excellent review article; “Ultrasound of tibialis anterior muscle and tendon: anatomy, technique of examination, normal and pathologic appearance” (2013).
Due to the functional impairment I referred this patient to orthopaedics for a potential surgical repair. There is support in literature for surgical repair. Sammarco et al. (2009) concluded in their study that surgical repair can be beneficial regardless of age, sex, medical comorbidity, or delay in diagnosis. They noted however that early repair is less complex.
Main learning points:
1. Patients with chronic tibialis anterior rupture can present mostly with pain in the peroneal musculature due compensatory overuse/muscle spasm.
2. Surgical repair can be a good option regardless of age, sex, medical comorbidity, or delay in diagnosis.