The subacromial space is the anatomical region limited superiorly by the acromion and the coracoacromial ligament and inferiorly by the glenoid fossa and the humeral head. In humans, the main tissues that form it and that can be affected by subacromial impingement syndrome are the subacromial bursa and the supraspinatus tendon. The syndrome is the most common degenerative pathology affecting the human shoulder, and it is characterized by an uncertain etiopathogenesis. We compared different anatomical parameters of the scapula related to the subacromial impingement syndrome in humans, between modern humans and 2 species of African apes (Pan troglodytes and Gorilla gorilla). The 3 species we studied are orthograde primates and they present a similar structural pattern of the scapula and subacromial space, but anatomical differences exist owing to different types of locomotion used. The main differences indicate that African apes present a more curved and tilted acromion than humans, which does not, however, imply a difference in the relative size of the subacromial space among the 3 species studied. Humans also have a lower value of the relative size of the supraspinatus fossa than African great apes, and in human females have a relative lower value than males. We studied the anatomical structures of the shoulder in African apes that researchers have related to subacromial syndrome in humans to achieve a better understanding of the etiopathogenesis of the syndrome.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Price excludes VAT (USA)
Tax calculation will be finalised during checkout.
Aiello, L., & Dean, C. (1990). An Introduction to human evolutionary anatomy. London: Academic Press.
Anetzberger, H., Maier, M., Zysk, S., Schulz, C., & Putz, R. (2004). The architecture of the subacromial space after full thickness supraspinatus tears. Zeitschrift für Orthopadie und Ihre Grenzgebiete, 142, 221–227.
Aoki, M., Ishii, S., & Usui, M. (1986). The slope of the acromion and rotator cuff impingement. Orthopaeidic Transactions 10, 228.
Banas, M. P., Miller, R. J., & Totterman, S. (1995). Relationship between the lateral acromion angle and rotator cuff disease. Journal of Shoulder and Elbow Surgery, 4, 454–461.
Bartolozzi, A. R., Andreychik, D., & Ahmad, S. (1994). Determinants of outcome in the treatment of rotator cuff disease. Clinical Orthopaedics and Related Research, 308, 90–97.
Bigliani, L. U., Morrison, D. S., & April, E. W. (1986). The morphology of the acromion and its relationship to rotator cuff tears. Orthopaedic Transactions, 10, 228.
Brox, J. I., Staff, P. H., Ljunggren, A. E., & Brevik, J. I. (1993). Arthroscopic surgery compared with supervised exercises in patients with rotator cuff disease (stage II impingement syndrome). British Medical Journal, 307, 899–903.
Chard, M. D., Hazleman, R., and Hazleman, B. L. (1991). Shoulder disorders in the elderly: A community survey. Arthritis and Rheumatism, 34, 766–769.
Chen, S. K., Simonian, P. T., Wickiewicz, T. L., Otis, J. C., & Warren, R. F. (1999). Radiographic evaluation of glenohumeral kinematics: A muscle fatigue model. Journal of Shoulder and Elbow Surgery, 8, 49–52.
Ciochon, R. L., & Corruccini, R. S. (1977). The coracoacromial ligament and projection index in man and other anthropoid primates. Journal of Anatony, 124, 627–632.
Corruccini, R. S., & Ciochon, R. L. (1976). Morphometric affinities of the human shoulder. American Journal of Physical Anthropology, 45, 19–38.
Edelson, J. G., & Taitz, C. (1992). Anatomy of the coraco-acromial arch. Relation to degeneration of the acromion. Journal of Bone and Joint Surgery, 74, 589–594.
Farley, T. E., Neumann, C. H., Steinbach, L. S., & Petersen, S. A. (1994). The coracoacromial arch: MR evaluation and correlation with rotator cuff pathology. Skeletal Radiology, 23, 641–645.
Freese, A. (1998). Anatomische Untersuchungen zur ossären Morphologie und Stellung des Akromions und deren Bedeutung für die Ätiologie des Impingement-Syndroms. Ph.D. Dissertation. University of Aachen.
Gohlke, F., Barthel, T., & Gandorfer, A. (1993). The influence of variations of the coracoacromial arch on the development of rotator cuff tears. Archives of Orthopaedic and Trauma Surgery, 113, 28–32.
Hashimoto, T., Nobuhara, K., & Hamada, T. (2003). Pathologic evidence of degeneration as a primary cause of rotator cuff tear. Clinical Orthopaedics and Related Research, 415, 111–120.
Hawkins, R. J., & Dunlop, R. (1995). Nonoperative treatment of rotator cuff tears. Clinical Orthopaedics and Related Research, 321, 178–188.
Howell, S. M., Imobersteg, A. M., Seger, D. H., & Marone, P. J. (1986). Clarification of the role of the supraspinatus muscle in shoulder function. Journal of Bone and Joint Surgery of America, 68, 398–404.
Hyvonen, P., Paivansalo, M., Lehtiniemi, H., Leppilahti, J., & Jalovaara, P. (2001). Supraspinatus outlet view in the diagnosis of stages II and III impngement syndrome. Acta Radiologica, 42, 441–446.
Inmann, V. T., Saunders, J. B., & Abbott, L. C. (1944). Observations on the function of the shoulder joint. Journal of Bone and Joint Surgery, 26, 1–30.
Jacobson, S. R., Speer, K. P., Moor, J. T., Janda, D. H., Saddemi, S. R., & MacDonald, P. B. (1995). Reliability of radiographic assessment of acromial morphology. Journal of Shoulder and Elbow Surgery, 4, 449–453.
Jerosch, J., Castro, W. H., Sons, H. U., & Moesler, M. (1989). Zur Atiologie des subacromialen Impingement-Syndroms- eine biomechanische Untersuchung. Beitrage zür Orthopadie und Traumatologie, 36, 411–418.
Jurmain, R. (1989). Trauma, degenerative disease, and other pathologies among the Gombe chimpanzees. American Journal of Physical Anthropology, 80, 229–237.
Jurmain, R. (2000). Degenerative joint disease in african great apes: An evolutionary perspective. Journal of Human Evolution, 39, 185–203.
Kronberg, M., Nemeth, G., & Brostrom, L. A. (1990). Muscle activity and coordination in the normal shoulder. An electromyographic study. Clinical Orthopaedics and Related Research, 257, 76–85.
Larson, S. G., & Stern, J. T. (1986). EMG of scapulohumeral muscles in the chimpanzee during reaching and “arboreal” locomotion. American Journal of Anatomy, 176, 171–190.
Larson, S. G., & Stern, J. V. (1987). EMG of chimpanzee shoulder muscles during knuckle-walking: Problems of terrestrial locomotion in a suspensory adapted primate. Journal of Zoology London, 212, 629–655.
Lehman, C., Cuomo, F., Kummer, F. J., & Zuckerman, J. D. (1995). The incidence of full thickness rotator cuff tears in a large cadaveric population. Bulletin of the Hospital for Joint Diseases, 54, 30–31.
Leroux, J. L., Codine, P., Thomas, E., Pocholle, M., Mailhe, D., & Blotman, F. (1994). Isokinetic evaluation of rotational strength in normal shoulders and shoulders with impingement syndrome. Clinical Orthopaedics, 304, 108–115.
Lindblom, K. (1939). On pathogenesis of ruptures of the tendon aponeurosis of the shoulder joint. Acta Radiologica, 20, 563–577.
Liotard, J. P., Cochard, P., & Walch, G. (1998). Critical analysis of the supraspinatus outlet view: Rationale for a standard scapular Y-view. Journal of Shoulder and Elbow Surgery, 7, 134–139.
Lisy, M., Hreusik, P., & Steno, B. (2004). The shape of the acromion and its effect on the subacromial space. Acta Chirurgiae Orthopaedicae et Traumatologiae Cechoslovaka (Praha), 71, 110–114.
Lohr, J. F., & Uhthoff, H. K. (1990). The microvascular pattern of the supraspinatus tendon. Clinical Orthopaedics and Related Research, 254, 35–38.
Lovell, N. (1990). Skeletal and dental pathology of free-ranging mountain gorillas. American Journal of Physical Anthropology, 81, 399–412.
Ludewig, P. M., & Cook, T. M. (2002). Translations of the humerus in persons with shoulder impingement symptoms. Journal of Orthopaedic and Sports Physical Therapy, 32, 248–259.
MacGillivray, J. D., Fealy, S., Potter, H. G., & O’Brien, S. J. (1998). Multiplanar analysis of acromion morphology. American Journal of Sports Medicine, 26, 836–840.
Mayerhofer, M. E., & Breitenseher, M. J. (2004). Impingement syndrome of the shoulder. Radiologe, 44, 569–577.
Morrison, D. S., & Bigliani, L. U. (1987). The clinical significance of variations in acromial morphology. Orthopaedic Transactions, 11, 234.
Neer, C. S. (1972). Anterior acromioplasty for the chronic impingement syndrome in the shoulder: A preliminary report. Journal of Bone and Joint Surgery, 54, 41–50.
Nirschl, R. P. (1989). Rotator cuff tendinitis: Basic concepts of pathoetiology. In Instructional Course Lectures, vol. 38 (pp. 439–445). Park Ridge, Illinois: The American Academy of Orthopaedic Surgeons.
Ogata, S., & Uhthoff, H. K. (1990). Acromial enthesopathy and rotator cuff tear. A radiologic and histologic postmortem investigation of the coracoacromial arch. Clinical Orthopaedics, 254, 39–48.
Poppen, N. K., & Walker, P. S. (1976). Normal and abnormal motion of the shoulder. Journal of Bone and Joint Surgery of America, 58, 195–201.
Prato, N., Peloso, D., Franconeri, A., Tegaldo, G., Ravera, G. B., Silvestri, E., et al. (1998). The anterior tilt of the acromion: Radiographic evaluation and correlation with shoulder diseases. European Journal of Radiology, 8, 1639–1646.
Prescher, A. (2000). Anatomical basics, variations, and degenerative changes of the shoulder joint and shoulder girdle. European Journal of Radiology, 35, 88–102.
Putz, R., Liebermann, J., & Reichelt, A. (1988). Funktion des Ligamentum coraco-acromiale. Acta Anatomica, 131, 140–145.
Rathburn, J. B., & Macnab, I. (1970). The microvascular pattern of the rotator cuff. Journal of Bone and Joint Surgery, 52, 540–553.
Reddy, A. S., Mohr, K. J., Pink, M. M., & Jobe, F. W. (2000). Electromyographic analysis of the deltoid and rotator cuff muscles in persons with subacromial impingement. Journal of Shoulder and Elbow Surgery, 9, 519–523.
Roberts, D. (1974). Structure and function of the primate scapula. In F. A. Jenkins (Ed.), Primate locomotion (171–200). New York: Academic Press.
Seok-Beom, L., Eiji, I., Shawn, W., & Kai-nan, A. (2001). Contact geometry at the undersurface of the acromion with and without a rotator cuff tear. Arthroscopy, 17, 365–372.
Tasu, J. P., Miquel, A., Rocher, L., Molina, V., Gagey, O., & Blery, M. (2001). MR evaluation of factors predicting the development of rotator cuff tears. Journal of Computer Assisted Tomography, 25, 159–163.
Thompson, W. O., Debski, R. E., Boardman, N. D., Taskiran, E., Warner, J. J., and Fu, F. H. (1996). A biomechanical analysis of rotator cuff deficiency in a cadaveric model. American Journal of Sports Medicine, 24, 286–292.
Toivonen, D. A., Tuite, M. J., & Orwin, J. F. (1995). Acromial structure and tears of the rotator cuff. Journal of Shoulder and Elbow Surgery, 4, 376–383.
Tuttle, R. H., & Basmajian, J. V. (1978). Electromyography of pongid shoulder muscles. Part II, deltoid, rhomboid, and “rotator cuff.” American Journal of Physical Anthropology, 49, 47–56.
Van der Windt, D. A., Koes, B. W., de Jong, B. A., & Bouter, L. M. (1995). Shoulder disorders in general practice: Incidence, patient characteristics, and management. Annals of the Rheumatic Diseases, 54, 959–964.
Vaz, S., Soyer, J., Pries, P., & Clarac, J. P. (2000). Subacromial impingement: Influence of coracoacromial arch geometry on shoulder function. Joint Bone Spine, 67, 305–309.
Wang, J. C., Horner, G., Brown, E. D., & Shapiro, M. S. (2000). The relationship between acromial morphology and conservative treatment of patients with impingement syndrome. Orthopedics, 23, 557–559.
Warner, J. J., Micheli, L. J., Arslanian, L. E., Kennedy, J., & Kennedy, R. (1990). Patterns of flexibility, laxity and strength in normal shoulders and shoulders with instability and impingement. American Journal of Sports Medicine, 18, 366–375.
Wickiewicz, T. L. (1994). Glenohumeral kinematics in a muscle fatigue model: A radiographic study. Orthopaedic Transactions, 18, 178–179.
We thank Dr. Juan Francisco Pastor (Department of Human Anatomy and Embryology, University of Valladolid), Dr. Eulalia García (Natural Science Museum of Barcelona), and Dr. Salvador Moyà-Solà and Ms. Teresa Esquirol (Palaeontology Museum Miquel Crusafont, Sabadell) for their contribution to the preparation of this study. We also thank Drs. Alberto Prats-Galino and Anna Puigdellívol (Department of Human Anatomy and Embryology, University of Barcelona), Mr. Manuel Barba, and Mr. Sebastián Mateo (Service of Corpse Donation and Dissecting Room, University of Barcelona) and Ms. Carme Sanahuges (Gimbernat Physical Therapy School, Sant Cugat del Vallès) for their support and collaboration.
About this article
Cite this article
Potau, J.M., Bardina, X. & Ciurana, N. Subacromial Space in African Great Apes and Subacromial Impingement Syndrome in Humans. Int J Primatol 28, 865–880 (2007). https://doi.org/10.1007/s10764-007-9167-z