Efficacy of zoledronic acid combined with locking proximal humeral plate in treatment of proximal humeral osteoporotic fractures

Abstract

Objective To evaluate the clinical effect of zoledronic acid combined with locking proximal humeral plate in the treatment of proximal humeral osteoporotic fractures in elderly patients. Methods A retrospective analysis was made on the data of 30 elderly patients with complete follow-up after surgically treated proximal humeral osteoporotic fractures between January 2012 and May 2015. There were 12 male and 18 female patients, with age range of 60-86 years (mean, 69.5 years). According to the Neer classification system, five patients had two-part fractures, nineteen three-part fractures and six four-part fractures. No open injury or combined vascular and nerve injuries occurred. All patients had open reduction and internal fixation with locking proximal humeral plate. The patients were divided into basic treatment group (anti-osteoporosis therapy with oral calcium carbonate and calcitriol was administered after operation, n=14) and combined treatment group (intravenous zoledronic acid was used after operation in addition to the basic treatment, n=16) according to the random number table. Neer score of the shoulder joint was recorded at admission and at postoperative 1 year. Bone healing and subsequent refracture were assessed with X-ray postoperatively. Dural energy X-ray absorptiomery (DXA) was used to detect bone mineral density of the left hip at admission and one year after operation. Refracture was recorded within one year after operation. Results All patients showed bone union without the presence of delayed union or non-union.Bone union time was (17.32±3.41) weeks in combined treatment group and (18.24±3.74) weeks in basic treatment group (P>0.05). After one year, shoulder function score presented the good-excellent rate of 81% in combined treatment group and 79% in basic treatment group (P>0.05). Improved bone mineral density was seen in both groups one year after operation [control group: neck (0.651±0.070)g/cm2, Ward area (0.477±0.049)g/cm2, greater trochanter (0.569±0.073)g/cm2; combined treatment group: neck (0.631±0.075)g/cm2, Ward area (0.498±0.050) g/cm2, greater trochanter(0.576±0.069)g/cm2], but the change was only significant in combined treatment group (P<0.05). There was one patient with Colles fracture of the left distal radius, one T12 vertebral compression fracture and one L3 vertebral compression fracture in basic treatment group, but no new fractures occurred in combined treatment group. Conclusion Zoledronic acid combined with locking proximal humeral plate in the treatment of proximal humeral osteoporotic fractures can restore shoulder function, significantly increase bone mineral density, and decrease incidence of subsequent fractures. Key words: Osteoporotic fractures; Humeral fractures; Phosphonic acids; Locking plate