Assessment of efficacy of charnley type and modular type total hip prosthesis in patients undergoing total hip arthroplasty: A comparative study

Abstract

Background: Arthroplasty is an operation to restore pain free motion to a joint and function to the muscles, ligaments and other soft tissue structures that control the joint. Evaluation of the long-term outcomes of an operative procedure is important to determine the durability of the results of the procedure. In addition, it provides a mean for comparison with the results of any changes in the procedure, including alterations in operative technique, implant design, type of joint - cemented and non-cemented hybrid that occur over times. Hence; we evaluated the results of total hip arthroplasty specially comparing most commonly performed modular type with charnley type i.e. fixed type of THR. In our institute modularity in respect to neck length is used.Materials & methods: 30 patients of either sex, who were operated for total hip replacement, were assessed. Each case was subjected to detailed history regarding age at operation, sex, indication of surgery, type of replacement, duration after replacement, any associated comorbid condition that may affect outcomes of total hip replacement, whether joint replacement was unilateral / bilateral. A scoring system used by Harris called as Harris hip scoring system was used to evaluate the patients. 100 points will be given to a person who can painlessly walk without any support or limp and the walkable distance should not be limited. All the results were analyzed by SPSS software. Results: 2(13.33%) patient in Charnley Group developed dislocation which was managed by closed reduction and traction for 6 weeks. 1(6.67%) Patient in Charnley Group developed peri prosthetic fracture which was managed by open reduction and internal fixation with plating and circlage wire. No patient in the group both groups had shortening more than 2 cms. There was no lengthening in any of the patients. The average Harris Hip Score in Modular Group patients was 85.67 and in Charnley Group was 79.87. Conclusion: Since appreciable limb length shortening and dislocation of hip after fixed type is seen in this study so our results shows that Modular type of hip prosthesis is better than fixed type prosthesis (Charnley type hip prosthesis).