Shepherds Fracture Causes, Symptoms and Treatment

Shepherds Fracture Overview

 

Shepherds fracture is the fracture of the lateral tubercle of posterior process of the talus and is sometime mistaken for symptomatic Os Trigonum.

 

Possible Causes of Shepherds Fracture

  • Inversion ankle injury / sprain may avulse tubercle leaving posterior talofibular ligament intact
  • Extreme ankle plantarflexion / equinus

 

Symptoms of Shepherds Fracture

  • Patients may present with ankle sprain history or symptoms
  • Patient may have posterolateral ankle tenderness on palpation
  • Pain with range of motion of ankle joint, especially with plantar flexion of the ankle
  • Motion of the great toe may cause pain to the back of the ankle as flexor hallucis longus rubs over the fracture site (between medial and lateral tubercle)

 

Imaging

    – lateral x-ray view of the foot:

  • postero-lateral tubercle is seen on the lateral view 

    – MRI:

  • look for marrow edema in the back of the talus
  • with fluid surrounding the Os and associated marrow edema (absence of talar marrow edema), then consider os trigonum as the cause of symptoms

 

Shepherd’s Fracture Treatment

  • minimally displaced fractures are treated with short leg cast for 4 to 6 weeks
  • non-unions are common and surgical excision of the ununited fragment thru a posterolateral ankle arthrotomy is recommended