Impingement Sign

Purpose: To assess for impingement of the talocrural joint.

Test Position: Sitting.

Performing the Test: Grasp the patient's calcaneus with one hand and the forefoot of the patient with a second hand to bring the patient's foot into a position of plantarflexion. The examiner then places his/her thumb over the anterolateral aspect of the ankle and brings the foot into dorsiflexion and eversion. A positive test results when the patient experiences pain with pressure over the anterolateral ankle and when the pain response is greater with the ankle in dorsiflexion and eversion than in plantar flexion. 

Diagnostic Accuracy: Sensitivity: .95; Specificity: .88; -LR: .06; +LR: 7.9 .

Importance of Test: The closed packed position of the talocrural joint is full dorsiflexion. During the impingement sign test, the patient is brought into the closed packed position, placing several connective tissues and muscles on passive tension. Additionally, the trochlear surface of the talus is wider anteriorly than posteriorly. When the patient is brought into dorsiflexion, the concave tibiofibular segment of the ankle mortise is brought into increased contact with the talus, creating a wedging (impinging) effect.

Note: these tests should only be performed by a properly trained health care practitioner.

References:   Flynn , Timothy. Users' Guide to Musculoskeletal Examination. USA: Evidence in Motion, 2008. Print.              
  Neumann, Donald. Kinesiology of the Musculoskeletal System. 2nd Edition. Mosby Printing Inc. Print.