In the operation of the proximal humeral fractures in elderly patients, there are some problems due to osteoporosis. Previously we reported the correlation between BMD and the stability of screw fixation about the proximal humeral fracture model. Also we reported regional difference in BMD within the proximal humeral head in cadavers. In this paper we analyzed BMD in the proximal humeral heads of living bodies to confirm regional differences of BMD within the proximal humeral head. BMD of 10 cases, 20 proximal humeral heads (mean age 67.7 yrs.old ) was analyzed by Discovery A ( Discovery A, Hologic Co.). BMD was measured at 4 regions of interest (ROI) ; top of the humeral head(A), the middle of the humeral head(B), surgical neck(C) and the greater tuberosity(D). We analyzed the BMD value at each ROI and compared the dominant side with non-dominant side. Mean BMD ( g/cm2 )A was 0.48, B 0.35, C 0.29 and D 0.39. There was significant difference between A vs. B, A vs. C, A vs. D and C vs. D (p < 0.05). However there was not a significant difference between the dominant side and the non-dominant side. Our results show that there is a significant difference of BMD is in the proximal humeral head. To get good stability of the screws fixation, the edge of the screw must be inserted just beneath the top of the proximal humeral head.
