Osteochondritis Disecans: Current Knowledge and Paleopathological Findings in Southern Patagonia.

SUBY JA

Buenos Aires

Congreso; VI Paleopathology Association Meeting in South America; 2015

Paleopathology Association

Osteochondritis dissecans (OCD) is the detachment of a portion of articular subchondral bone (Schenck and Goodnight 1996; Edmonds y Polousky 2013). Its pathophysiology is unknown and there is no consensus concerning its etiology and treatment (Edmonds y Polousky 2013). Inflammation, spontaneous and avascular necrosis, genetics and repetitive trauma are possible causes, been the last one the most accepted. OCD usually involves the knee, ankle, elbow and shoulder in that order, more frequently in males, although cervical vertebrae and phalanges of the great toe are also affected (Edmonds y Polousky 2013; Waldron 2009). Despite its frequent description in skeletal remains, only few researches focused on OCD (e.g. Wells 1974; Silva 2001; Kothari et al. 2009; Vikatou 2012). The aim of this presentation is to study the prevalence of OCD in a skeletal sample of hunter-gatherers from Southern Patagonia and to explore its possible association with economical patterns previously proposed for human population of this region.Skeletal remains of 26 adult individuals from Southern Patagonia were studied. Articular subchondral lesions compatible with OCD were searched, identified as ?crater like? depressions (Aufderheide y Rodríguez-Martín 1998; Capasso et al. 1998; Ortner 2003; Waldron 2008). Differences between sex, age and dietary patterns were statistically analyzed by χ2 test.Forty two percent (11 out of 26) of the skeletons showed at least one lesion, three of them bilateral. Fifteen lesions were identified: 10 (72%) in scapulae (7 right and 3 left), 2 (20%) in the first phalange of the great toe, 1 (6.7%) in proximal right ulna and 1 (6.7%) in the right superior articular facet of one axis (Figure 1). Males showed higher prevalence (52% - 10 out of 19; P=0,039) than females (14.3%; 1 out of 7). The prevalence was similar between young adults (44%; 4 out of 9) and medium adults (41.1%; 7 out of 17). Finally, individuals with terrestrial diet showed higher prevalence (58%; 7 out of 12) than skeletons with marine diet (16%; 1 out of 6; p=0.04) and similar than those with mixed diet (42%; 3 out of 7) (Figure 2). The studied sample showed a high prevalence of OCD. Differently than in current populations, shoulder was the most affected joint, involving only men. It was observed that sports involving elbow and shoulder increased the frequency of OCD in these joints (Hefti 1999). Moreover, Merbs (1983) found that archery could be a possible cause of high frequency of OCD between Saldermuit. Similar causes must be considered as related with OCD of the shoulder in men with terrestrial economies from Southern Patagonia, where the use of arch was frequent as hunting tool.