FOOT &ANKLE INTERNATIONAL Copyright  2006 by the American Orthopaedic Foot & Ankle Society, Inc. Commentary on the Clinical Diagnosis of Achilles Tendon Rupture James F.S. Ritchie, F.R.C.S. (Orth.); Dishan S. Singh, F.R.C.S. (Orth.) Stanmore, Middlesex, U.K. INTRODUCTION For more than 40 years, the calf-squeeze test has played an important role in the assessment of Achilles tendon injuries. The first account was published by Simmonds in 1957. 4 Five years later, in 1962, Thomson 6 made a retrospective and unsubstantiated claim to have discovered the test in 1955. In terms of the detail of how the calf squeeze test should be performed, and what it showed, Simmonds’ and Thompson’s descriptions are practically indistinguish- able. There was, however, a great difference between the contexts in which they placed and understood the tech- nique. Thompson’s papers 5.6 focused very specifically on the test and its supporting anatomical dissections, with only a brief account of the other clinical features of the condition. Simmonds’ paper, 4 on the other hand, gave a detailed account of all of the clinical features of Achilles tendon rupture and how they might be used to distinguish it from tears of the muscle bellies. Although the calf squeeze test formed an important part of his diagnostic examination, it was just one part of a complex picture; the history, the resting posture of the foot (Figure 1), and the presence of a palpable gap also were important. Although Simmonds 4 himself did not use the phrase, it is this clinical triad of a palpable gap, an abnormal resting posture or “angle of dangle” of the foot, and the calf squeeze test that form his version of this test. If applied properly, it gives a comprehensive assessment of the Achilles tendon and can be used to identify both acute and late-presenting or neglected ruptures. With chronic ruptures, the “angle of dangle” often remains abnormal even though the calf- squeeze test may be equivocal or apparently normal. All three elements should be considered rather than the isolated results of the calf-squeeze test in the evaluation of a patient with a suspected Achilles tendon injury. Corresponding Author: James F.S. Ritchie, F.R.C.S. (Orth.) 1 Fairmount Briar, Croft Road Crowborough, East Sussex England TN61NQ E-mail: james.Ritchie@doctors.org.uk For information on prices and availability of reprints, call 410-494-4994 X226 A B Fig. 1: The “angle of dangle.” Decreased plantarflexion of the right foot at rest due to rupture of the tendon of Achilles. Unfortuantely, Simmonds’ work has largely been over- looked outside the United Kingdom, with the result that his clinical triad remains relatively unknown to the wider orthopaedic community. Even today the observation of an 1161