#### What you need to know A 41 year old man complains of longstanding pain at the back of his left heel and stiffness when he gets up. The pain is worse when he plays tennis. He asks for advice on what it is and what can be done. Pain at the back of the heel arises from a limited number of anatomical structures: the Achilles tendon, the calcaneal bursa, or the surrounding soft tissues (fig 1⇓). This limits the likely differential diagnoses. Achilles tendinopathy is the most common cause of posterior heel pain.1 Its incidence is estimated at 1.85 per 1000.2 It is also important to note that Achilles tendinopathy may underlie other pathologies, particularly partial tears of the Achilles tendon.3 Fig 1 Anatomy of the heel ### Take a history Begin by understanding the pain: see table 1⇓ and figure 1⇑ …