History, Physical Examination, Radiographic Anatomy, and Biomechanics and Physiological Function of the Rotator Cuff Maxwell C. Park, MD,* James E. Tibone, MD, †,‡ and Thay Q. Lee, PhD § Management of symptomatic rotator cuff tears involves obtaining a careful history and performing a thorough physical examination. Imaging studies can confirm the working diagnosis, and supplement treatment decision making. Understanding the biomechanics and function of the rotator cuff is important when considering the surgical options during repair to optimize the outcomes for a given individual. Oper Tech Sports Med 20:201-206 © 2012 Elsevier Inc. All rights reserved. KEYWORDS biomechanics, rotator cuff, shoulder History O btaining a meaningful history involves accounting for the patient’s occupation and handedness. Considering the chronicity of the symptomatic tear involves considering an acute event versus an overuse environment, and the pos- sibility of a combination of scenarios. An acute tear may lead to a more predictable outcome in the context of truly chronic tears being associated with muscle atrophy and fatty infiltra- tion that may be irreversible. Each patient may present dif- ferent functional goals after surgery, and this will frame the reasonable expectations that can be achieved after repair. Beyond occupation, therefore, the patient’s recreational ac- tivities and sport activities, if any, must be taken into account. Physical Examination A careful physical examination begins with inspection. The affected extremity may manifest atrophy; gross atrophy within the scapular fossae could be diagnostic for a rotator cuff tear, although a spinoglenoid notch cyst would be in the differential diagnoses, however. Passive range of motion is critical to assess to eliminate a concurrent frozen shoulder, a condition that precludes immediate repair. Excessive exter- nal rotation relative to the normal shoulder may signify a torn subscapularis tendon. Active range of motion generally will gauge the functional limitations the patient may have. Motor testing can isolate the muscles involved. Resisted forward elevation in the scapular plane can help assess su- praspinatus involvement, although a negative test does not mean a tear is not present, especially when the tear is only partial, leaving a tear that is functional on examination. In addition to elevation, the supraspinatus rotates the humerus internally and externally. Weakness to external rotation at the side generally means the patient has supra- and infraspi- natus involvement—this test, in our experience, is the most specific way to rule-in a supraspinatus tear. However, a neg- ative test does not preclude a supraspinatus tear, although the tear may be full thickness, as it may be only partially torn in the anterior–posterior dimension. The belly-press, lift-off, and bear-hug tests can help measure subscapularis pathol- ogy. The belly-press test is performed with the hand pressing maximally into the abdomen and the elbow in line with the trunk in the sagittal plane—a positive test is manifested by a relative weakness compared with the normal side or the el- bow dropping posteriorly in the sagittal plane. The lift-off test is performed by placing the dorsum of the hand against the midlumbar spine (L2–L4)—a positive test is apparent when the patient is unable to internally rotate and lift the hand away from the back. The bear-hug test is performed with hand placed on the contralateral shoulder over the acromio- clavicular joint—a positive test results when the examiner can externally rotate the hand away from the initial position. *Southern California Permanente Medical Group, Woodland Hills, CA. †Department of Orthopaedic Surgery, University of Southern California, Los Angeles, CA. ‡Kerlan-Jobe Orthopaedic Clinic, Los Angeles, CA. §VA Long Beach Healthcare System, University of California, Irvine, CA. Address reprint requests to Maxwell C. Park, MD, Department of Orthopae- dic Surgery, Kaiser Foundation Hospital, Woodland Hills Medical Center, 5601 De Soto Ave, Woodland Hills, CA 91365. E-mail: maxwellpark1@yahoo.com 201 1060-1872/12/$-see front matter © 2012 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1053/j.otsm.2012.09.008