The Medium-Term And Long-Term Outcome Of Whom Use Bone-Sparing Non-Stemmed Hip Prosthesis

OBJECTIVE:To evaluate the medium-term and long-term outcome of whom use bone-sparing non-stemmed hip prosthesis(NSHP).METHODS:Forty-two patients(48 hips) with hip diseases, who were treated by NSHP at the department hospital of Guangxi Zhuang Autonomous Region between 2003 and 2005. Patients were followed-up once every other 6 months in the postoperative first year, then once every years from the second year. The follow-up visit included functional evaluation and X-ray evaluation.①Functional evaluation:Use Harris joint function scale to evaluate the hip function of the replacement with NSHP before and after.②X-ray evaluation:A standardized radiographic assessment was performed using an anteroposterior X-ray of the pelvis. The following radiological data were recorded:preoperative grade of osteoarthritis as classified according to the method from Busse et al, preoperative grade of femoral head necrosis as classified according to the method from Ficat et al, inclination angle of the operated and the untreated side, heterotopic ossifications, as classified according to the method of Brooker et al.③Postoperative medium-term and long-term adverse events and complications were observed and revision operation was performed if necessary.RESULT:Follow-up of 66-87 months (average 78.2±6.3 months) showed satisfactory outcome with total excellent of 95.2%.①Postoperative functional evaluation results of patients:During follow-up visit, hip joints of 47 hips were still in situ, pain lessened or disappeared in 40 patients (95.2%,40/42).The average Harris hip score was 87.9±10.1 postoperative compared with 56.9±10.6 preoperative. It showed significant difference between the postoperative average Harris hip score and preoperative one (P<0.05).②X-ray evaluation results of patients:Preoperative osteoarthristis classification:3 hips had grade 2 joint degeneration,7 hips had grade 3 joint degeneration. Preoperative avascular necrosis of femoral head classification: Out of 28 hips with avascular necrosis of femoral head,20 hips had stage 3 femoral head necrosis, and 8 hips had stage 4 femoral head necrosis. The inclination angle averaged 131.8°±3.8°on the treated side and 128.9°±2.3°on the untreated side. Heterotopic ossifications classification:2 hips had postoperative heterotopic ossifications,1 hip had grade 1 heterotopic ossification,1 hip had grade 2 heterotopic ossification.③Revision operation:1 patient (2.5, 1/42)required a revision total hip arthroplasty due to screw of prosthesis breakage. Good bone stock of the proximal femur was found in the patient which allowed implantation of a conventional medullary anchored prosthesis. This revision surgery and postoperative rehabilitation were uncomplicated.④dverse events and complications:Femoral neck prosthesis depressed occurred postoperatively in 1 patient (2.38%,1/42).Other complications included hip pain (n=2).CONCLUSION:NSHP provides biological fixation for femoral prosthesis by bone proliferation through the windows with connective tissues surrounding the prosthesis and has the charactedistics of low stress and deformation, high intensity and rigidity, and anti-loosening, thus, may prolong its live time. Revision surgeries are facilitated by the good bone stock remaining in the proximal femur. After the replacement, patient hips lessened or disappeared, function, malformation, sphere of activities are clearly battle. The medium-term and long-term effects of total hip arthroplasty are satisfying.