Enthesopathies (lesions of muscular insertions) as indicators of the activities of Neolithic Saharan populations.код для вставкиСкачать
AMERiCAN JOURNAL OF PHYSICAL ANTHROPOLOGY 71:221-224 (1986) Enthesopathies (Lesions of Muscular Insertions) as Indicators of the Activities of Neolithic Saharan Populations 0. DUTOUR Laboratoire de Gbologie du Quaternaire, C. N.R.S., Centre Uniuersitaire de Luminy, 13288 Marseille, Cedex 9, France. KEY WORDS medicine Paleopathology, Overuse syndromes, Sporting Enthesopathies are bony lesions involving the sites of inserABSTRACT tion of muscles or ligaments. Those caused by hyperactivity of the relevant muscles may be distinguished clearly from those of metabolic or inflammatory origin. Observations from sporting and occupational medicine indicate that specific enthesopathies are correlated with different activities. Examination of the enthesopathies present on two groups of well-preserved neolithic skeletons from separate regions of the Sahara with different paleoenvironments show that overall 20% of the skeletons presented lesions. Three different forms of enthesopathy involved the arm, principally the elbow, and may be tentatively correlated with javelin throwing, wood cutting, and archery. Two types of lesion involving the foot were observed in skeletons from a hunter-gatherer population and may be correlated with much walking or running over hard ground. I suggest that the analysis of such lesions on ancient skeletons may, in concert with other archaeological data, throw light on the activities of ancient people. Bony lesions a t the sites of muscles or tendon insertions on the skeleton, or enthesopathies, are well known in sporting and occupational medicine to be associated with prolonged hyperactivity of the relevant muscles. A notorious example is "tennis elbow," where lesions at the sites of insertion of specific muscles on the lateral epicondyle of the humerus may result in a hyperostosis that is sometimes visible on radiological examination. Other enthesopathies are quite specifically associated with over use of different sets of muscles. Such lesions may be confidently detected on well-preserved skeletal remains, and they may provide indications about the muscular activities of the individuals examined and, hence, about the habitual activities of the populations to which they belonged. In this article some typical enthesopathies found on skeletons from two different neolithic Saharan populations are described, and the implications for the physical activities of these groups will be discussed. MATERIALS AND METHODS This study was performed on two different neolithic Saharan populations that have been 0 1986 ALAN R. LISS, INC. more fully described elsewhere (Dutour and Petit-Maire, 1983; Dutour, 1984;Paris, 1984). The study groups consist of 1) a collection of 25 skeletons (eight male, five female, 12 unsexable) from the Saharan region of Mali Hassi el Abiod (19"06'N, 3" 50'W). This population is being investigated as part of a study of the Saharan paleoenvironment under the direction of Nicole Petit-Maire (C.N.R.S. Luminy). Archeological data indicate that this population inhabited a lacustrine environment and that fish were a major item of their diet. Radiocarbon dating places the age of these skeletons at 7,000-6,000 years BP (Petit-Maire and Riser, 1983). The second group was a collection of 16 skeletons (five male, two female, nine unsexable) from the Chin-Tafidet site (17" 30'N, 6" 20'E) in the Niger. This population consisted of hunter-gatherers and dates from 4,000-3,000 years BP (Paris, 1984). Skeletons from the two sites are frequently complete and in a good state of preservation; the index of preservation does not differ sigReceived January 15,1986;revision accepted Apyil7,1986 222 0. DUTOUR flattened, slightly curved exostoses are present on the posterior superior faces of the right and left olecranon processes (Fig. 2). The lesions are more pronounced on the right side. In both cases the articular surfaces appear normal. The lesions reflect stress on the lower insertion of the triceps brachii tendon. The triceps is a powerful muscle and is composed of three separate elements with individual upper insertions but a single common insertion on the olecranon. It is uniquely responsible for extension movement of the elbow, and the common insertion site is subject to microtrauma during complete elbow extension, particularly when the triceps brachialis muscle is fully extended and working at full RESULTS power. These conditions are ideally met when Nine of the skeletons examined (22%) the arm is horizontal and the elbow flexed showed the presence of one o r more enthesop- (Kapandji, 1983). Under modern conditions, athies. These were more frequent in the pop- the lesion is observed in wood cutters, blackulation from the Niger (7/16) than in that smiths, and some baseball players. The pafrom Mali (2/25). In eight cases the subject thology may be unilateral or bilateral, was male: The ninth skeleton could not be depending on the type of activity involved. sexed with certainty. The ratio of sexed skelBiceps brachii enthesopathies etons to total skeletons was significantly more important for those presenting lesions In three cases, two mature adult males (8/9) than in the whole population observed from the Niger and one mature adult of un(20/41). This discrepancy is probably due to determined sex from Mali, unilateral right the fact that the enthesopathies could be ob- side lesions consisting of roughness, spicules, served on the best preserved skeletons, which and osteophytes are present on the radial could also be sexed. Three different lesions tuberosity. This is the site of insertion of the (six cases) involved the arm, particularly the biceps brachii muscle, which is the principal elbow. The remaining four cases showed two agent responsible for flexion of the elbow. different lesions of the bones of the foot. This type of enthesopathy is rather rare today (Genety, 1972) and is associated with Enthesopathy of the medial epicondyle of the carrying heavy loads with the elbows bent humerus (masons, bakers). It is seldom unilateral. One of the skeletons from the Niger with In one case, a mature adult male from the Niger, a small bony pad is present on the this lesion was particularly well preserved, lower edge of the right medial epicondyle of and examination of other lesions was possithe humerus and extends into a vertically ble, leading to a new hypothesis. An osteodescending osteophyte near the epicondyle phytic band bordering a n imprint is visible (Fig. I). The rest of the distal epiphysis is on the coronoid process of the right ulna. normal as are the right radius and ulna. No Assembly of the joint demonstrated that this lesions were found on the corresponding left corresponded to the location of the trochlea of the humerus a t submaximal (120") elbow elbow region. This lesion reflects a n insertion pathology flexion. Further, the left humerus shows a corresponding to hyperactivity of the mus- distinct modification consisting of a small cles pronator teres, flexor carpi radialis, pal- bony patch on the distal face of the olecranon maris longus, flexor digitorum superfkialis, fossa a t the contact with the olecranon proand flexor carpi ulnaris or of the ligament. It cess at full elbow extension. In addition, comis observed today in sporting medicine and parison of the paired humeri shows a generally affects javelin throwers or golf profound asymmetry: The insertions of the triceps brachii muscle are far more developed players. on the left side, but the teres minor is much Triceps brachii enthesopathies more prominent on the right side. These obIn two cases a juvenile adult male from the servations indicate that the right arm was Niger and a n aged male from Mali, large, submaximally flexed at the elbow against a nificantly between the two sites. Only skeletons of adults with preserved long bones were considered in this study, since significant enthesopathies are chiefly observed on the limb bones, and immature individuals would not be expected to have experienced a sufficiently long overuse of specific muscles for bony lesions to have formed. Enthesopathies were evaluated by nakedeye examination of the bones for rough patches, irregularities, or osteophytes. They were classified by comparison with radiological data from modern subjects suffering from enthesopathies of known aetiology (La Cava, 1959). ENTHESOPATHIESAND NEOLITHIC ACTIVITIES Fig. 1. Enthesopathy of the medial epicondyle of the humerus. Exostosis at the distal edge of the medial epicondyle of the humerus. Fig. 2. Triceps brachii enthesopathy. Exostosis in the form of a spur at the top of the olecranon (insertion of m. triceps brachialis). 223 biceps brachialis b);and exostosis a t the insertion of m. biceps brachialis (c). Fig. 4. Adductor hallucis enthesopathy. Calcaneum: Exostosis at the insertion of Achilles tendon (white arrow) and at the insertion of m. adductor hallucis (black arrow). Fig. 3. Biceps brachii enthesopathy. Tuberosites radii Normal bone (a); irregularities a t the insertion of m. strong force with a n external rotation of the in modern marathon and long-distance runshoulder, while the left arm was extended ners (Clement et al., 1984).This skeleton also and submitted to compressive force. This cor- shows a plantar enthesopathy (see below). responds perfectly to the movement of a n Adductor hallucis enthesopathies archer. I n three cases, two mature adult males and Achilles tendon enthesopathy one juvenile adult male all from the Niger, a In one case, a mature adult male from the fine, pointed bony spur extends to the posteNiger, the posterior portion of the only cal- rioinferior tuberosity of the calcaneum. For caneum found bears a vertically orientated two of the skeletons only one calcaneum was exostosis. This enthosopathy, which involves present. In the third case the lesion was bithe insertion of the Achilles tendon, is seen lateral. This type of lesion indicates a plan- 224 0.DUTOUR tar enthesopathy involving the adductor hallucis muscle. It is observed mainly among people who do much walking or running on hard sufaces (joggers) (Lehman, 1984). DISCUSSION Activity-induced pathology could be a good tool with which to approach activities of ancient populations (Merbs, 1983). This study describes the bony lesions involving the insertions of muscles or ligaments in ancient skeletons and attempts to relate them to causative muscular activities using knowledge derived from sports and occupational medicine. The mechanism of formation of the lesions, bony spurs, rough patches, and irregularities involves active bone formation and thus cannot reflect postmortem changes. Furthermore, enthesopathies caused by muscular hyperactivity are generally isolated lesions and may be readily distinguished from those caused by metabolic or inflammatory causes, e.g., rheumatoid arthritis, ankylosing spondylitis, or psoriasic arthritis, where the joint surfaces are involved. Similarly, the calcifications associated with Forestier disease (or DISH) are widespread and involve the vertebrae. I am thus confident that the enthesopathies described here may be related to prolonged and extensive use of the correpsonding muscles. At the present time only the bony spur on the calcaneum occurs as a spontaneous lesion, and that particularly in old, overweight women. All three skeletons with this lesion in the present study belonged to quite young males, in whom spontaneous occurrence is rare. While the observed lesions may confidently be described to the extensive use of certain specific groups of muscles, the identification of the precise activity involved remains more speculative. The lesions of the elbow observed are related in modern conditions to javelin throwing, wood cutting, and archery, which are all quite possible activities within the archeological context of these people. Differences in the incidence of lesions between the two populations may reflect differences in their life-styles. The Mali group lived in a lacustrine environment, and the abundance of large fish bones and the presence of harpoon heads indicates that fishing was a major activity for them. They provide only two cases, one possible archer and a possible wood cutter. The bow is used for fishing in certain primitive populations, and certain of the harpoon heads found at this site are compatible with mounting as arrowheads. Remains of antelopes and other animals are also found at this site, as are a few classical flint arrowheads. The “wood cutter” lesion should be compatible with the action of casting a weighted net. No lesions of the foot were observed. The population from the Niger, by contrast, had a high incidence of lesions, which may be related to their activities as hunter-gatherers. In particular, the incidence of foot lesions may reflect long and strenuous exertion on hard and stony ground. It may also be noteworthy that no lesions were found on unequivocally female skeletons from either site. In conclusion, the study of enthesopathies present on ancient skeletons may provide additional data that, taken with other archaeological findings, can help in interpreting the activities of ancient man. ACKNOWLEDGMENTS I thank S. and E. Bernus (Orstom Paris) for support and T. Greenland (C.N.R.S. Lyon) for his assistance in preparing the manuscript. I a m indebted to G. Meyer for helpful discussion. The skeletons from the Chin-Tafidet site were studied with the kind permission of Franqois Paris (Orstom Niamey), director of a program of prehistorical and anthropological research in the southern Sahara. Figures 1-4 were generously provided by Franqois Paris. LITERATURE CITED Clement, DB, Taunton, JE, and Smart, GW (1984) Achilles tendinitis and peritendinitis: Etiology and treatment. Am J. Sports Med. 12179-184. Dutour, 0 (1984) Extension saharienne du type anthropologique de Mechta-Afalou. Cah Orstom, ser G601, XIV,2t209-211. Dutour, 0, and Petit-Maire N (1983)S4pultures et restes osseux. In N Petit-Maire and J Riser (eds): Sahar;. ou Sahel? Le quaternaire recent du Bassin de Taoudenni (Mali). Marseille: Lamy, pp. 274-306. Genety, J (1972) La maladie des insertions des tendons. Cah. Med. Lyon 48:4685-4690. Kapandji, IA (1983) Physiologie articulaire. Schemas commentes de Mecanique humaine Maloine, Paris It98-99. LaCava, G (1959)L’enthesite ou maladies des insertions. Presse MQd67:9. Lehman, WL, Jr. (1984) Overuse syndromes in runners. Am. Family Phys. 29t157-161. Merbs, CF (1983) Patterns of activity-induced pathology in a Canadian Inuit population. Archaeological Survey of Canada Paper. Mercury series 119. Canada: National Museum of Man. Paris, F (1984) La region d‘hgall-Tegiddan Tesent (Niger). Programme Archbologique d’Urgence 1977-1981. 111. Les Sepultures du Neolithiques final a 1’Islam. Etudes Nigeriennes 503-72. Petit-Maire N, and Riser J (1983) Sahara ou Sahel? Le quaternaire recent du Bassin de Taoudenni (Mali). Marseille: Lamy.