Function after revision of failed total hip arthroplasty

Measurements of functional performance were made before and 6 months after 31 primary total hip replacements and 31 total hip revisions for prosthetic loosening. After revision, functional performance returned to levels substantially the same as after primary hip replacement except for greater reliance on canes for patients in the revised group. Ratings of hip status and hip pain were slightly less satisfactory after revision as compared to after the primary operation.     

Femoral revision in hip resurfacing compared with large-bearing metal-on-metal hip arthroplasty

It has been suggested that revision of the femoral component of hip resurfacing after femoral failure would be straightforward and have an outcome comparable to primary total hip arthroplasty (THA). We have compared the outcome of femoral side-only revision resurfacings to the results of primary modular large-bearing metal-on-metal THA. Fourteen consecutive patients underwent revision surgery of the failed femoral component, to a cemented tapered stem (CPT, Zimmer, Warsaw, Indiana) with a large modular metal head (Smith and Nephew Orthopaedics Ltd, Memphis, Tennessee, or Adept, Finsbury Orthopaedics, Surrey, England). The acetabular component was found to be well fixed, well orientated, and was left in situ. The 14 matched patients in the primary THA group received the same components. At a mean follow-up of 49 months (range, 30-60 months), clinical outcome measured using the Oxford and Harris Hip Scores showed no significant difference (P = .11, P = .45, respectively). Operative time and blood loss were comparable for both groups. We conclude that revision of the failed femoral resurfacing component gives excellent results.     

Femoral neck fractures after hip resurfacing

Femoral neck fracture is an important early complication after hip resurfacing. Our aims were firstly to determine the incidence of fracture in an independent series and secondly, in a case control study, to investigate potential risk factors. Fifteen femoral neck fractures occurred in a series of 842 procedures, representing an incidence of 1.8%. No relationship existed between age, sex, and fracture incidence. Mechanical factors such as notching, femoral neck lengthening, and varus alignment of the femoral component were found to have a similar incidence in both fracture and control groups. The proportion of patients that had at least 1 mechanical risk factor was not different between the 2 groups (fracture group, 50%; control group, 41%). Established avascular necrosis of the femoral head was evident in all retrieved femoral heads (n = 9) of patients who sustained postoperative fracture; in none of these patients was avascular necrosis the initial diagnosis. This study suggests that in our practice, mechanical factors, such as neck notching, neck lengthening, or varus angulations, are not the primary cause of femoral neck fractures.     

Complications after metal-on-metal hip resurfacing arthroplasty

This article determines the incidence and cause of the complications commonly associated with metal-on-metal hip resurfacing implants and the proposed methods to prevent these complications. The literature available in PubMed was reviewed. Complication rates after hip resurfacing are low, and the procedure has shown both safety and efficacy in the hands of surgeons trained in specialized centers. Proper surgical technique can further reduce the incidence of femoral neck fracture, component loosening, and abnormal wear of the prosthesis. A more systematic detection of adverse local tissue reactions is needed to provide accurate assessments of their prevalence.     

Incidence of heterotopic ossification after hip resurfacing

BACKGROUND: Heterotopic ossification has been noted around total hip arthoplasty in numerous studies. With hip resurfacing growing in popularity, we have prospectively evaluated the incidence in a cohort undergoing hip resurfacing. METHODS: Two hundred and twenty consecutive hip-resurfacing procedures were prospectively reviewed at a minimum of 2 years follow up to assess the incidence of heterotopic ossification and its effect on function and clinical outcome. We also reviewed the preoperative diagnosis, age, sex and previous surgery. RESULTS: The overall percentage of heterotopic ossification was 58.63%. The incidence of Brooker 1 was 37.27%, Brooker 2 was 13.18% and Brooker 3 was 8.18%. Male osteoarthritis had the highest incidence of heterotopic bone formation (HBF). Three men underwent excision of heterotopic bone, two for pain and stiffness and one for decreased range of movement. Both anteroposterior and lateral radiographs were reviewed for evidence of HBF. In all, 12.7% had no evidence of HBF in the first view but clearly had in the second view. CONCLUSIONS: Overall, we found no evidence that HBF affected the clinical or functional outcome of the hip resurfacing at a mean of 3 years follow up. However, in light of the high incidence of HBF seen in a yet unproven long-term prosthesis, we conclude that the Cochrane database recommendations with regard to prophylaxis should be implemented.     

Short-term functional outcome after hip resurfacing surgery

Hip resurfacing arthroplasty is a popular method for treating late stage osteoarthritis, especially in young and active patients. Most studies presenting short-term follow-up after hip resurfacing present radiographic or dual clinician-patient-related outcome. These kinds of outcomes are influenced by interpretation of the clinician and do not tell us much about functional outcome from the patients perspective. Today, functional outcome is often measured using patient-reported outcome instruments. We used the patient-reported ‘Hip Disability and osteoarthritis Outcome Score’ questionnaire, which has good measurement properties, to assess short-term functional outcome in 160 patients (mean follow-up of 2.6 years) after hip resurfacing surgery. Furthermore, we focused on pain, range of motion, subjective improvement and complications. The majority (86.9%) of patients was free of pain after surgery and range of motion improved significantly. Subjective improvement was indicated in 95% of the patients. Mean HOOS in 149 patients was 87.5. In total, there were 11 complications (6%), and deep infections contributed the most (3.4%). In general, short-term follow-up after hip resurfacing in this cohort showed good clinical and patient-reported functional outcome. When assessing the results of medical interventions, a good PRO instrument can give reliable and valuable information from the patients perspective.     

金属对金属髋关节表面置换术的短期随访研究

目的探讨金属对金属(MOM)混合固定型髋关节表面置换术(HRA)的近期疗效,分析手术技术要点。方法 2004年10月至2008年6月,对52例(58髋)股骨头缺血性坏死、骨关节炎、髋关节发育不良、强直性脊柱炎患者行MOM-HRA。其中男32例,女20例;年龄16～65岁,平均42.6岁。手术方法按照K.De.Smet标准方法进行,术后对Harris评分、关节活动度和X线片进行随访。结果失访7例(8髋),45例(50髋)获得随访,随访时间平均22个月(12～54个月)。术前平均Harris评分(37.0±1.2)分,术后22个月平均(93.0±1.0)分;术前屈髋度平均(25.3±1.6)°,术后22个月平均(105.0±1.8)°;术前外展度平均(18.8±0.8)°,术后22个月平均(40.6±1.0)°。评价:46髋优,3髋良,1髋差。无股骨颈骨折,无松动,无脱位,无感染,无翻修,1例异位骨化BrookerⅢ型。结论 HRA具有保留股骨头骨量、术后关节活动度恢复快、近期结果好等优点,对于获得优良的术后结果,严格的患者选择和精确的手术技术至关重要。     

金属对金属全髋关节表面置换术的近期疗效

 目的 分析金属对金属全髋关节表面置换术的近期疗效, 探讨其适应证选择和技术要点。方法 2006 年1 月至2010 年10 月因股骨头坏死、髋关节骨关节炎、髋关节发育不良、强直性脊柱炎接受全髋关节表面置换术104 例(116 髋), 其中男59 例(66 髋), 女45 例(50 髋);年龄16~67 岁, 平均39.7 岁。均采用Conserve Plus 假体, 依据比利时技术标准完成全髋关节表面置换术。术后1 个月、3个月、6 个月、1 年及之后每年随访一次, 摄X 线片并统计Harris 髋关节评分。结果 101 例(112 髋)获得随访, 随访率97.1豫。随访时间9~66 个月, 平均33个月。Harris髋关节评分由术前平均(37.6±6.3)分提高至末次随访时(91.3±5.3)分, 其中优104 髋、良7 髋、差1 髋, 优良率99.1%(111/112)。末次随访时, 髋臼假体外展角36°~55°, 平均42.7°;股骨假体柄干角132°~146°, 平均138.5°。随访期间出现异位骨化2 例(2.0豫, 2/101), 分别为Brooker III型1 例及Brooker II型1 例, 均无症状, 未予处理。术后并发假体脱位1 例(1.0%, 1/101), 经手法复位及卧床1 个月治愈, 未再发生脱位。无股骨颈骨折、假体松动、感染及翻修病例。结论 严格选择手术适应证, 配合精确的手术技术, 金属对金属髋关节表面置换术可获得良好的近期疗效。     

Femoral neck narrowing after metal-on-metal hip resurfacing

We reviewed 40 Corin Cormet 2000 (Corin, Cirencester, UK) metal-on-metal resurfacing hips, in 36 patients, for the presence of femoral neck narrowing. A neck-to-prosthesis ratio was calculated by dividing the diameter of the femoral neck with that of the implant. This ratio was measured on plain anteroposterior pelvis radiographs taken immediately and 2 years postoperation. Subsequent radiographs were measured up to a maximum 7 years (mean, 5.3 years) postoperation. Femoral neck narrowing was observed in 90% of hips at 2 years, with the average neck narrowing ranging from a ratio of 0.865 to 0.811. Importantly, no further narrowing occurred beyond this point up to 7 years postoperation. We described a simple reproducible method of measuring neck narrowing on plain radiographs and discuss possible causal factors for neck narrowing after hip resurfacing.     

Meperidine-induced seizure after revision hip arthroplasty

Musculoskeletal injuries secondary to seizures are well documented and have a variable incidence. Meperidine (Demerol [Abbott, Abbott Park, IL]) has been used for many years in the postoperative setting for pain control; however, in high doses, it has been associated with seizure. We report the case of patient who experienced a tonic-clonic seizure 5 days after hip revision surgery, resulting in dissociation of the socket from the acetabulum with an associated acetabular fracture. In this patient, meperidine administered for patient-controlled analgesia within recommended range caused the seizure.     

Femoroacetabular cup impingement after resurfacing arthroplasty of the hip

Femoroacetabular cup impingement (FACI), defined as the presence of a bony spur or indentation at the femoral neck corresponding to the abutment site of metallic cup, was observed in 9 (11%) of the 84 hips with contemporary resurfacing arthroplasty of the hip. All FACIs occurred in men after a mean of 14 months (range, 8-24 months) postoperatively. Five patients had persistent groin pain if the hip was moved into flexion, abduction, and external rotation. One patient sustained a late-onset fracture through the femoral neck already weakened by postoperative change of osteonecrosis. Mean postoperative Harris hip score in the FACI group was poorer than that in the non-FACI group (P = .003). Multiple logistic regression analysis showed a significant association of FACI with a low acetabular cup inclination (odds ratio, 1.42; 95% confidence interval, 1.01-1.99; P = .046) and a high cup uncoverage ratio (odds ratio, 1.36; 95% confidence interval, 1.01-1.84; P = .045).     

全髋关节置换及翻修术后坐骨神经损伤的原因探讨

目的 通过对655例行全髋关节置换及翻修术患者的回顾性分析，探讨术后出现坐骨神经损伤的原因并提出相应的预防措施。方法 1998年1月～2001年12月，对655倒髋关节病变的患者行手术治疗．其中全髋关节置换术587例，全髋关节翻修术68例，术后有9例出现坐骨神经损伤．发生率为1.37％。其中8例发生在全髋关节置换术后，1例发生在全髋关节翻修术后，9例患者中，男3例，女6例；年龄35～67岁，平均51岁，9例患者中4例因股骨头缺血性坏死、2例因先天性髋臼发育不良合并髋关节骨关节炎、1例因强直性脊柱炎合并髋部病变、1例因类风湿关节炎合并髋部病变、1例因全髋关节假体松动而行全髋关节置换术。非骨水泥固定8例，骨水泥固定1例。9例坐骨神经损伤的患者中．7例因肢体不等长而同时行下肢延长术．2例因髋部强直而同时行松解术，结果 9例术后出现坐骨神经损伤的患者．8例为单纯腓总神经损伤．临床表现为足不能背伸；1例为腓总神经和胫神经联合损伤．临床表现为足不能背伸和跖屈。术后随访6～48个月，平均31个月.其中8例患者术后半年坐骨神经功能全部恢复；1例患者术后半年坐骨神经功能仍未恢复．遂行切开探查松解术．探查术后1年坐骨神经功能部分恢复。结论 全髋关节置换及翻修术后坐骨神经损伤．多由下肢过度延长或机械性压迫所致，大多数不完全损伤可以恢复.     

Results of hip resurfacing

Background  

The renewed popularity of resurfacing hip arthroplasty in the last 10 years has generated a remarkable quantity of scientific contributions based on mid- and short-term follow-up. More than one paper has reported a consistent early revision rate as a consequence of biological or biomechanical failure. Two major complications are commonly described with resurfacing implants: avascular necrosis and femoral-neck fracture. A close relationship between these two events has been suggested, but not firmly demonstrated, whereas cementing technique seems to be better understood as potential cause of failure.     

Noninflammatory pseudotumor simulating venous thrombosis after metal-on-metal hip resurfacing

Metal-on-metal hip resurfacing has become a widespread procedure, especially in young, physically active patients. Pseudotumor is a new complication that can occur after hip resurfacing and metal-on-metal total hip arthroplasty (THA). This article presents a case of a 37-year-old woman who underwent metal-on-metal resurfacing of the left hip for symptomatic osteoarthritis. Twelve months following implantation, the patient reported painless swelling of the left lower leg. There was no clinical evidence of a deep venous thrombosis. Ultrasound and computed tomography showed a solid cystic lesion in the iliopsoas muscle, which communicated with the hip joint and compressed the external iliac vein. As a consequence, the cystic lesion was resected marginally. A few months later, the patient reported some discomfort in the groin and symptoms of instability, metallic clicking, and a restricted range of motion. Clinical and radiological examination revealed normal findings. Determining the serum concentration of cobalt and chromium revealed high increased levels of these metal ions. Ten months following excision of the pseudotumor, the patient reported recurrent swelling of the left lower leg. Computed tomography of the affected area showed a lobulated cystic formation; therefore, a relapse was suspected. At the second revision, the mass was excised and the implant was revised to a conventional ceramic-on-ceramic THA. At 30-month follow-up, the patient was doing well and there were no signs of local recurrence. Additionally, the metal ion levels of cobalt and chromium in the blood had significantly decreased.     

Sporting activity after hip resurfacing: changes over time

The evolution of patient sporting activities after hip resurfacing has not yet been studied. A scoring algorithm to quantify sporting activity was developed to compare type of activity, frequency, duration, and overall activity level in the early postoperative period and at mid- to long-term follow-up. Quantification of sporting activity is a challenging undertaking but should become a useful tool to study the relationship between failure rates and the use of prosthesis.     

Femoral component neck fracture after failed hip resurfacing arthroplasty

Failure on the femoral side after third-generation metal-on-metal hip resurfacing arthroplasty is suggested to be easily treated with conversion to conventional total hip arthroplasty. Clinical results of conversion for failed hip resurfacing arthroplasty with the use of primary femoral implants confirmed this for a short-term follow-up. We present a case of the occurrence of a stemmed femoral implant neck fracture in a patient who was earlier treated for a failed hip resurfacing. We advise to consider acetabular revision in case of (suspected) acetabular metal damage and to use a stem component with a relative large neck diameter.     

Femoral neck bone mineral density after resurfacing hip arthroplasty

Introduction: Resurfacing hip arthroplasty (RHA) has been suggested to provide an alternative to conventional total hip arthroplasty in younger, active patients. It seems to have an ability to conserve the bone mass on the femoral side. Some controversy exists regarding to the possible disadvantages of RHA and some of them are connected to poor femoral bone quality after surgery. Hence we wanted to study the bone mineral density changes 3 and 12 months after RHA. Materials and Methods: A total of 26 patients (22 men and 4 women, 28 hips) underwent a hip resurfacing arthroplasty. The mean age of the patients was 55,2 (range 38-69) years. Bone mineral density (BMD) of the proximal femur was measured by using the dual-energy X-ray absorptiometry (DXA) postoperatively and within 3 and 12 months from surgery. For analysis, we divided the femoral neck area into four equal-sized regions of interest ranging from the prosthesis to the trochanter level. Results: At three months follow-up the BMD changes varied between -5.1% (ROI C) and + 1.9% (ROI A), as compared with the immediate postoperative values. After one year follow-up the BMD changes were + 1.1% in the ROI A, + 5.4% in the ROI B, -3.9% in the ROI C and + 1.3% in the ROI D. The changes in BMD were not statistically significant. Discussion: While there is still much debate and room for additional research in this topic, the results suggest that BMD is conserved in the femoral neck one year after hip resurfacing arthroplasty.