Objective To compare the clinical outcomes between proximal femoral nail antirotation (PFNA) combined with zoledronic acid and PFNA only in the treatment of osteoporotic intertrochanteric fracture in the elderly patients.Methods A retrospective analysis was made on 72 patients that completed the follow-up after PFNA for osteoporotic intertrochanteric fracture from November 2011 to May 2014.According to the application of zoledronic acid (5 mg,once a year) after PFNA,the patients were divided into study group (n =30) and control group (n =42).Bone healing and subsequent refracture were assessed with X-ray postoperatively.Harris hip score was recorded.Bone mineral density before operation and one year after operation were compared between the two groups.Adverse effect of zoledronic acid was recorded during hospitalization.Results Mean period of follow-up was 15 months (range,12-26 months).One year after operation,Harris score,new fracture incidence,mean fracture union time were (82.65 ± 6.24) points,3％ (1/30) and (14.26-± 2.24) weeks in study group,while (81.85 ± 5.38) points,14％ (6/42) and (15.26 ± 3.05) weeks in control group.There were no statistical differences between the two groups (P ＞ 0.05),but the subsequent fracture was higher in control group.One year after operation,lumbar and contralateral non-injury hip bone marrow density were (0.78 ± 0.16)g/cm2 and (0.71 ± 0.14)g/cm2 in study group,higher than (0.75 ± 0.13)g/cm2 and (0.69 ±0.13)g/cm2 in control group (P ＜0.05).But there were no significant differences between the two groups before operation.All fractures were healed at postoperative 1 year.No intolerable adverse events occurred in study group.Conclusions PFNA is effective in the treatment of osteoporotic intertrochanteric fracture.In the meantime,the combination with zoledronic acid has no influence on bone healing while increasing bone mineral density,and may decrease the occurrence of subsequent fragile fractures.