The Method To Avoid Lengthening Lower Limbs After Total Hip Arthroplasty In Patients With Congenital Short Femoral Neck

Objective To discuss the method to avoid lengthening lower limbs after total hiparthroplasty (THA)in patients with congenital short femoral neck.Methods The clinical data was analyzed retrospectively, from38patients ndergoingunilateral THA between April2005and October2010. There were26males and12females, aged45-78years (mean,62.3years). Among these cases, there were11casesof avascular necrosis of the femoral head,17cases of hip osteoarthritis and10cases offemoral neck fracture. Before operation,29cases had leg length discrepancy; Allpatients had hip pain, including24cases lamp,4cases the waist pain. Preoperative CTmeasuring the length of the femoral neck patients was31.8~38.9mm. An average of35.3mm. Preoperative29cases of lower limbs differ long, clinical measurement bodyshortening10~24mm, an average of14.5mm; X-ray body measurement shortening ofthe11~25mm, an average of14.7mm. Preoperative Harris score of44.0+/-3.6points.There are always hip surgery history. Intraoperative in hip dislocation before a sword inbig rotor vertex electricity to make a mark point, and then in the acetabular vertex fixedgram is a needle, needle fixed on single suture, primary total hip and knee unbend alongthe femoral the vertical axis will suture led to marked points along the marked pointscut, keep suture prosthesis implantation to measure the length of the limbs for change.Prosthesis implantation reset after testing molds hip, dislocation of lower limbs backbefore the position, once again, measuring big rotor marked points and stitched thedistance between the far end. General line THA recommended to keep proper femoralneck length, cut bone surface determined for small rotor top10~15mm is advisable. For patients with congenital short femoral neck, use the shortest femoral head can alsocause the body extension, so through the reduction to adjust the length of the femoralhead long body cannot take place. In addition, deepen acetabular can adjust body length,but deepen acetabular and the adjustment of measures when the body length is difficult,so only shortening the feasible method from the femoral can be repeated shorteninguntil the corolla of lower limbs. If the routine procedure sure osteotomies in small rotorsurface above10~15mm, even if intraoperative use short femoral neck prosthesis(head and neck false body length46mm) can also cause patients limb extended. So, forsuch patients intraoperative cut bone to determine the femoral neck patients with normaldifferent, this group of patients in little rotor osteotomies plane above5~10mm. Thechange of the body length by intraoperative hang line or art taken X-ray measurement.If limb is still extend, can continue to cut bone to corolla of lower limbs.Results After one day,by clinical and X-ray measurement, the3patients have lowerlimbs extending, the lower limbs were extended12,16,21mm by clinical measurement,and extend the13,16,22mm by X-ray measuremen. The rest of the35patients oflower limbs by clinical measurement have the difference of2~8mm, average4mm;X-ray measurement of1~9mm, average5mm;<10mm, as corolla. The total corollarate was92.1%(35/38). Postoperative patients incision all healed well, no infection,lower limb of deep vein thrombosis and related complications. Postoperative36caseshad been followed up, follow-up time12to68months, an average of43.8months. Onecase of extending16mm had obviously abnormal gait after three weeks, increased theheel pad still had mild limp;2cases had mild limp. The rest cases with corolla werenormal in walking, the hip pain relieve significant. Six months after surgery thepatient’s Harris score of86.7±2.3points, compared with the preoperative statisticalsignificance was found between (t=3.260, P=0.031). No prosthesis had found loosingand sinking by X-ray. Conclusion As technology maturity and THA clinical application, accepting THAsurgery patients with congenital short femoral neck will more and more, for suchpatients should be paid attention to in the art of lower limb length measurement and cutbone in the plane of the sure, sometimes intercepted more femoral neck not only won’tcause the stability of prosthesis decline, also can avoid the lower extremities caused aseries of complications of long range. is it different in revision Rates and the jointfunction between congenital short femoral neck patients and ordinary hip replacementpatients, still need to be further follow-up. All patients in our group used the femoralhandle, can we increase the femoral neck osteotomy for short femoral neck patientschoosing the prosthesis no femur handle, Still need further observation and research.