Total Hip Arthroplasty with Short Stem in Youth Patients with Rheumatoid Arthritis

Abstract：Objective To investigate the short-time clinical efficacy of total hip arthroplasty with short stem in youth pa-tients with rheumatoid arthritis.Methods From March 2012 to May 2013,15 patients(20hips)under went total hip arthro-plasty with short stem in youth patients with rheumatoid arthritis with Dorr C femoral canal in our hospital. There were 10 males (14 hips)and 5 females(6 hips),aged from 22 to 35 years(average,26. 5 years). All patients had a certain degree of osteo-porosis. According to Singh index classification:Singh typeⅡof 6 hips,Singh type Ⅲ of 14 hips. The postoperatively X-ray ex-amination was performed to analyze the location of femoral prostheses and evaluate the stability of the prosthesis-bone inter-face.Harris score was used to evaluate the hip function.Results All patients were followed up for anaverage of 27 months (range,16 to 41 months). The Harris hip score was improved from preoperative(62. 1 ± 8. 7)to(94. 5 ± 3. 6)at finial fol-low-up,there were significant difference before and after operation(t=9. 8,P=0. 000)in Harris score. The initial postopera-tive X-ray showed good canal filling in all chimney-type femoral canals. All patients had obvious thickening of femoral bone cortex in finial follow-up. 15 hips had different degree of femoral proximal stress shelter bone absorption,type one( The femur had bone loss)of 12 hips,type two( The lesser trochanter had bone loss)of 3 hips. This group of cases without thigh pain oc-curred.Conclusion With short stem has a good stem-canal fitting and bone-conserving in youth patients with rheumatoidar-thritis. Proximally porous-coated tapered designs with a reduced distal end of the stem can provide physiologic loading to the proximal part of the femur.