We examined the morphology of mammalian hips asking whether evolution can explain the morphology of impingement in human hips. We describe two stereotypical mammalian hips, coxa recta and coxa rotunda. Coxa recta is characterised by a straight or aspherical section on the femoral head or head-neck junction. It is a sturdy hip seen mostly in runners and jumpers. Coxa rotunda has a round femoral head with ample head-neck offset, and is seen mostly in climbers and swimmers. Hominid evolution offers an explanation for the variants in hip morphology associated with impingement. The evolutionary conflict between upright gait and the birth of a large-brained fetus is expressed in the female pelvis and hip, and can explain pincer impingement in a coxa profunda. In the male hip, evolution can explain cam impingement in coxa recta as an adaptation for running.
This was an international single blind phase-III study of patients undergoing orthopaedic surgery to assess the efficacy and safety of HBOC-201. Patients who were expected to require two or more units of red blood cells (RBC) were randomised to HBOC-201 or RBC. Efficacy was defined as the proportion of patients in the HBOC-201 group who did not receive RBC. The HBOC-201 group comprised 350 patients and the RBC group 338. At randomisation, mean haemoglobin levels were similar (~9 g/dl) in the two groups (p =0.760). In the HBOC-201 group, transfusion was avoided in 337 patients (96.3%) on day one, 246 patients (70.3%) through day seven, and 208 patients (59.4%) through day 42. Fewer units of allogeneic red cell units were administered in the HBOC-201 group than in the RBC group, namely 1.4 units v 3.1 units (p <
0.001). Adverse events in the HBOC-201 group were transient and mild in intensity and did not result in discontinuation of HBOC-201. There was no significant difference in mortality between the groups (p.=0.450). The efficacy of HBOC-201 was demonstrated by the avoidance of allogeneic RBC in about 60% of patients receiving this oxygen-carrying solution over a six-week period. HBOC-201 was well tolerated and appears to be a feasible alternative to RBC.
