Results of total hip arthroplasty in patients with reduced bone mineral density

Abstract

Total hip arthroplasty (THA) is one of the most common andclinically successfulorthopedic surgeries aimedto eliminate painand improve walking functionin patients with osteoarthritisof the III–IV stages. Low mineralbone density (BMD) affectsthe survivorship of implants after THA and may cause longrecoveryterms. Objective. Analyze the results THA in patientswith normal andlow BMD within a year after surgery. Methods.49 patients (aged 30‒75 years) were examined before and afteruncementedprimary THA. According to the results of two-photonX-ray absorptiometry before the surgery, they were divided intotwo groups: I, normal BMD — 27 (55.1 %) patients, T-criterionat the level of the proximal part of the unaffected femur ‒1 ormore; II, reduced BMD — 22 (44.9 %), T-criterion is smallerfor‒1. BMD, pain for VAS and function of the operated limbaccordingto Harris score, it was assessed before THA and one weeklater; 2, 6, 12 months. Biomechanical examinations of the bearingcapacity of the limb were performed before thesurgeryand6 months after. Results. On all terms of postoperative followup,the indicator forVAS in patients of the II group was statisticallyworse, but pain syndrome decreased in parallel. Harriship score was significantly lower in patients of the II group determinedbeforesurgeryand after it up to 2 monthsoffollow-up;after 6 months indicators became statistically similar. Accordingto the results of statography regardless of BMD before the surgicaltreatment, the average support on the affected limb was(12.7 ± 9.2) % less than healthy (p = 0.019). By 6 months afterTHA, the difference in foot load was insignificant (p = 0.675).Conclusions. One year after THA, recovery of function accordingto the Harris hip score established in bothgroups. However,this process occurs in patients with low BMDand took placemore slowly: only 6 months after surgery, the indicator leveledoff with the normal group BMD, 6 months after surgery in patientsof both groups, with the restoration of support on the operatedlimb during two-support standing was recorded.