Paper #14 - The distal biceps deficient arm, “the short arc syndrome”

Abstract

Introduction: Long term functional loss following a distal biceps rupture is difficult to quantify. Despite the 40% supination strength loss, some patients can successfully adjust to their weakness. 2 Freeman C.R. McCormick K.R. Mahoney D. Baratz M. Lubahn J.D. J Bone Joint Surg Am. 2009; 91: 2329-2334 Crossref PubMed Scopus (119) Google Scholar , 3 Morrey B.F. Askew L.J. An K.N. Dobyns J.H. J Bone Joint Surg Am. 1985; 67: 418-421 Crossref PubMed Scopus (431) Google Scholar , 5 Schmidt C.C. Brown B.T. Sawardeker P.J. DeGravelle Jr, M. Miller M.C. J Shoulder Elbow Surg. 2014; 23: 68-75 Abstract Full Text Full Text PDF PubMed Scopus (21) Google Scholar Their adaptation may occur by changing their supination movement. 5 Schmidt C.C. Brown B.T. Sawardeker P.J. DeGravelle Jr, M. Miller M.C. J Shoulder Elbow Surg. 2014; 23: 68-75 Abstract Full Text Full Text PDF PubMed Scopus (21) Google Scholar The purpose of this study is to measure the kinematic adaptation following a distal biceps rupture by using a novel timed isotonic supination test. We hypothesize that biceps deficient arms will compensate by shortening the forearm arc of supination, shifting the center of supination to a pronated position, and increasing the shoulder contribution. This kinematic adjustment could result in less supination power.