Figure 1. Anteroposterior radiograph of the right ankle.
Figure 2. Lateral radiograph of the right ankle.
A 21-year-old man presents to the office with posterior ankle pain that has persisted for a few months. The pain intensifies when he pushes off the foot during athletic activities. On physical examination, posterior ankle pain with hyperplantarflexion is noted. No tenderness over the Achilles tendon or the posterior subtalar joint is present, and the patient does not experience pain with passive flexion or extension of the great toe. Anteroposterior and lateral radiographs (Figures 1 and 2) are normal.
Can you diagnose this condition?
Submit your diagnosis to see full explanation.
Although pathology of the Achilles is the most common cause of posterior ankle pain, it can be challenging to diagnose because there are many possible etiologies. If the pain is located deep to the Achilles, retrocalcaneal bursitis, posterior impingement, and bony deformities should be suspected. Posterior impingement is a common source of posterior ankle pain and can affect bone or soft tissue. Bony impingement can occur between the posterior tibia and the calcaneus, which may be caused by an os trigonum, Stieda process, or osteophytes. Posterior pain and impingement of soft tissue can be caused by flexor hallucis longus (FHL) tendinitis and impingement of the joint capsule or surrounding muscles.
Posterior ankle impingement syndrome (PAIS) is a common condition found in athletes who engage in sports involving repetitive plantarflexion such as dance and soccer. Pain deep into the posterior ankle with forced hyperflexion is the most common finding of PAIS. It is crucial to rule out other causes of pain with a thorough physical examination. Pain with passive flexion and extension of the great toe may indicate FHL tendinitis. Pain with subtalar motion may indicate subtalar arthritis. Radiographs are often unremarkable with PAIS. Magnetic resonance imaging may show bone edema involving the lateral tubercle of the posterior talar process and is helpful in ruling out other pathology. PAIS often resolves with a period of rest and activity restriction.1,2
Dagan Cloutier, MPAS, PA-C, practices in a multispecialty orthopedic group in the southern New Hampshire region and is editor-in-chief of the Journal of Orthopedics for Physician Assistants (JOPA).
1. Maquirriain J. Posterior ankle impingement syndrome. J Am Acad Orthop Surg. 2005;13(6):365-371.
2. Yasui Y, Hannon CP, Hurley E, Kennedy JG. Posterior ankle impingement syndrome: A systematic four-stage approach. World J Orthop. 2016;7(10):657-663.