On-line version ISSN 2309-8309
Print version ISSN 1681-150X
SA orthop. j. vol.8 n.3 Pretoria Jan. 2009
J de BeerI; MG Pritchard II; CP RobertsII; DF du ToitIII
IMMed (Orthop); Orthopaedic Surgeon. Cape Shoulder Institute, Panorama, South Africa
IIFRCS (Tr & Orth); Shoulder Fellow. Cape Shoulder Institute, Panorama, South Africa
IIIDepartment of Anatomy and Histology, University of Stellenbosch, South Africa
The measurement of external rotation of the shoulder is commonly performed in two ways: with the arm adducted or with the arm abducted to 90°. This measurement forms an important part of the assessment of shoulder function.
It has been shown that the observer reliability of external rotation measurement is poor.1-4 Following the observation that the range of external rotation of the shoulder with the arm adducted altered depending on the exact position of the arm in the sagittal plane, we conducted a study to quantify the effect of a small increment of forward flexion (15°) on the range of external rotation.
External rotation of the shoulder was measured in 40 asymptomatic shoulders and 20 'frozen' shoulders with the arm in a vertical position and in 15° of forward flexion. The range of external rotation decreased significantly in forward flexion in both groups. External rotation decreased by an average of 16.9° in the asymptomatic group and 13.5° in the frozen shoulder group.
This study has shown that the sagittal position of the arm has an effect on the range of external rotation of the adducted shoulder. This may account for some of the observer variation in its measurement and affect the scores of certain outcome measures.
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1. Croft P, Pope D, Boswell R, Rigby A, Silman A. Observer variability in measuring elevation and external rotation of the shoulder. Br J Rheum 1994;33(10):942-6. [ Links ]
2. Hayes K, Walton JR, Szomor ZR, Murrell GA. Reliability of five methods for assessing shoulder range of motion. Aust J Physiotherapy 2001;47(4):289-94. [ Links ]
3. Hoving JL, Buchbinder R, Green S et al. How reliably do Rheumatologists measure shoulder movements? Ann Rheum Dis 2002;61(7):612-6. [ Links ]
4. Trifft PD, Wildin C, Hajioff D. The reproducibility of measurement of the shoulder. Acta Orthop Scand 1999;70(4):322-4. [ Links ]
5. Barnes CJ, Van Steyn SJ, Fisher RA. The effects of age, sex and shoulder dominance on range of motion of the shoulder. J Shoulder Elbow Surg 2001;10(3):242-6. [ Links ]
6. Notovny JE, Beynnon BD, Nichols CE 3rd. A numerical solution to calculate internal-external rotation at the glenohumeral joint. Clin Biomech 2001;16(5):395-400. [ Links ]
7. Pearl ML, Harris SL, Lippitt SB, Sidles JA, Harryman DT, Matsen FA. A system for describing positions of the humerus relative to the thorax and its use in the presentation of several functionally important arm positions. J Shoulder Elbow Surg 1992;1(2):113-8. [ Links ]
8. Constant CR, Murley AHG. A clinical method of functional assessment of the shoulder. Clin Orth 1987;214:160-4. [ Links ]
9. Browne AO, Hoffmeyer P, Tanaka S, An KN, Morrey BF. Glenohumeral elevation studied in three dimensions. J Bone Joint Surg [Am] 1990;72(5):843-5.
Dr J de Beer
Cape Shoulder Institute
PO Box 15741
Tel: +27 21 911-1017; Fax: + 27 21 911-1019
The content of this article is the sole work of the author. No benefits of any form have been derived from any commercial party related directly or indirectly to the subject of this article.