ObjectiveTo observe the influence of different humeral neck-shaft angle on the efficacy in the treatment of proximal humeral fractures with locking plate. MethodsA total of 106 patients with proximal humeral fractures were treated by locking plate between March 2009 and March 2013, and the clinical data were retrospectively analyzed. Of 106 cases, 58 were male and 48 were female, aged from 26 to 71 years (mean, 52.3 years). The causes were traffic accident injury in 54 cases, falling injury from height in 23 cases, falling injury in 21 cases, and others in 8 cases. According to the Neer classification, there were 32 cases of two-part fractures, 65 cases of three-part fractures, and 9 cases of four-part fractures. The time from injury to operation was 1-7 days (mean, 2.7 days). According to neck-shaft angle by X-ray measurements at 1-3 days after operation, the patients were divided into 3 groups:valgus group (>145°), normal group (126-145°), and varus group (<126°) to observe the influence of neck-shaft angle on efficacy. ResultsAccording to postoperative humeral neck-shaft angle, there were 10 cases in valgus group, 75 cases in normal group, and 21 cases in varus group. There was no significant difference in general clinical data among 3 groups (P>0.05). The patients were followed up 6-12 months. The X-ray results showed fracture healing, and no significant difference was found in fracture healing time among 3 groups (P>0.05). After 6 months, the varus angle of femoral head and visual analogue scale (VAS) score of normal group were significantly lower than those of valgus group and varus group (P<0.05). The excellent and good rate of Constant-Murley score was 78.67% (59/75) in normal group, and it was significantly higher than that in valgus group (60.00%, 6/10) and varus group (42.86%, 9/21) (P<0.05), but there was no significant difference between valgus group and varus group (P>0.05). The complication rate was 28.57% (6/21) in varus group, was 10.67% (8/75) in normal group, and was 20.00% (2/10) in valgus group, showing no significant difference among 3 groups (χ2=4.31, P=0.12). ConclusionReconstruction of normal neck-shaft angle is the key to good shoulder function and clinical efficacy in the treatment of proximal humeral fracture.