全髋翻修术后假体脱位的预防

目的：探讨采用后方关节囊重建方法对行后外侧入路全髋翻修术后假体脱位的防治作用。方法：本组45例（47髋）经后外侧入路行全髋翻修术的患者，男20例，女25例；平均年龄65岁（55-78岁）。术中将后方关节囊与外旋肌群分别重建固定于前上方原先切开的关节囊断端和大转子顶端的软组织处，回顾性分析术后假体脱位率及脱位的风险因素。股骨假体和髋臼假体均翻修29例（31髋），更换内衬5例（5髋），髋臼、股骨翻修的分别是10例（10髋）和1例（1髋）。第1次翻修的有29例（30髋），第2次翻修的有15例（16髋），第3次翻修的有1例（1髋）。X线评估包括翻修前后下肢长度，髋臼位相，股骨偏心距、前倾角和假体松动。临床功能评价采用Harris评分。结果：45例均获随访，平均随访时间2．7年，除1例感觉前方不稳外，无髋关节感染及脱位发生，该例X线片示髋臼假体过度前倾但无脱位发生。术后所有患者双下肢基本等长，髋臼外展角及前倾角、股骨偏心距和前倾角基本恢复至初次手术前水平。髋臼、股骨假体发生松动各1例。髋关节功能Harris评分由术前平均（49.13±15．53）分升至末次随访的平均（83．59±6.93）分（P〈0．05）。按Harris功能评分标准：优36髋，良5髋，可5髋，差1髋。结论：在假体安放正确、软组织张力恢复满意基础上，后方关节囊及外旋肌群重建有助于降低后外侧入路全髋翻修术后假体脱位的发生率。     

Late dislocation after total hip arthroplasty

BACKGROUND: Some patients have a dislocation for the first time many years after a total hip arthroplasty, but little is known about the risk factors and outcomes associated with late dislocation. The purposes of this study were (1) to determine the prevalence of late dislocation after total hip arthroplasty, (2) to characterize demographic and other factors associated with such late dislocations, and (3) to report the outcomes of such late dislocations. METHODS: Between 1969 and 1995, 19,680 primary total hip arthroplasties were performed in 15,964 patients at our institution. According to a prospective surveillance protocol, the patients were followed routinely at regular intervals and were specifically queried at each time-point about whether (and, if so, when) the hip had dislocated. First dislocations that occurred five years or more after the operation were defined as late dislocations. RESULTS: Five hundred and thirteen (2.6%) of the 19,680 hips dislocated. Of the 513 hips, 165 (0.8% of the entire cohort; 32% of the dislocated hips) first dislocated five or more years after the primary arthroplasty. The median time until the occurrence of these late dislocations was 11.3 years (range, five to 24.9 years) after the operation. Late dislocation was more frequent than early dislocation in women (p = 0.03), and late dislocation was associated with a younger age at the time of the primary total hip arthroplasty (median, sixty-three years) than was early dislocation (median, sixty-seven years) (p = 0.02). Clinical factors associated with late dislocation included previous subluxations without dislocation in twenty patients, a substantial episode of trauma in eleven patients, and onset of marked cognitive or motor neurologic impairment in eleven patients. Radiographically, the late dislocation occurred in association with polyethylene wear of >2 mm in eighteen hips, with implant loosening with migration or a change in position in eight, and with initial malposition of the acetabular implant (anteversion of <0 degrees or >30 degrees or abduction of >55 degrees) in thirty. Late dislocation recurred in ninety (55%) of the 165 hips and was treated with a reoperation in fifty-five hips (33% of the hips with late dislocation; 61% of the hips with recurrent dislocation). CONCLUSIONS: Late dislocation is more common than was previously thought. Several separate processes, some distinct from those associated with early dislocation, can lead to late dislocation. Late dislocation can occur in association with a long-standing problem with the prosthesis that manifests late (such as malposition of the implant or recurrent subluxation), it can occur in association with a new problem (such as neurologic decline, an episode of trauma, or polyethylene wear), or it can occur in association with any combination of these factors. The likelihood of the first late dislocation recurring is high.     

Early dislocation after total hip arthroplasty

Background The average incidence of dislocation after total hip arthroplasty is approximately 3%. However, the choice of surgical approach can affect the rate of postoperative dislocation. A 5.8% dislocation rate has previously been reported when a posterolateral approach was used compaired with 2.3% when an anterolateral approach was used. The aim of this study was therefore to assess the dislocation rate after total hip replacement with the posterolateral approach.Methods: Between January 1992 and December 1998, a posterolateral approach was used for 427 consecutive primary total hip replacements. There were 291 women and 136 men. The average age of the women was 71 years (range 40–91 years) and the average age of the men was 65 years (range 34–86 years). The one-year dislocation rate was recorded.Results: A total of 24 hip replacements (6 in men and 18 in women) dislocated. The one-year dislocation rate was 6/136 = 4.4% for men and 18/291 = 6.2% for women. The overall one-year dislocation rate was therefore 24/427 = 5.6%. The average delay between the operation and the dislocation was 7 weeks (range 1 day to 1 year).Conclusions Our results seem to confirm a high postoperative dislocation rate when the posterolateral approach is used. Most dislocations occured within the first 3 months after the surgery. An unexpected annual variation in the dislocation rate was found. No explanations was found for this variation.     

Early dislocation after total hip arthroplasty

We studied prospectively 499 cases of primary total hip arthroplasty done through an anterolateral approach to establish the early dislocation rate when restrictions on postoperative mobilization were not imposed. There were 3 early dislocations (within 6 weeks of surgery). All were reduced closed, and every patient subsequently achieved a stable hip without further intervention. Our results suggest that a low early dislocation rate can be achieved using an anterolateral approach without the need to restrict patients' postoperative mobilization. It may not be appropriate, however, to remove these restrictions when using other surgical approaches to the hip.     

Study of hip joint dislocation after total hip arthroplasty

The present study was undertaken to identify the factors responsible for hip joint dislocation after total hip arthroplasty, laying emphasis on analysis of the background variables of the patients. Of the 317 hips included in the study, ten (3.2%) dislocated. Only the anteversion angle of the cup differed significantly between the dislocation group and the dislocation-free group. The safe zone of the anteversion angle seems to be between 20 and 30 degrees. but it is also essential to set the antetorsion angle of the stem to match the shape of individual bones to create a more stable hip joint. This safe zone may be expanded by the additive effect of antetorsion angle of the stem.     

Prognosis of dislocation after total hip arthroplasty

One hundred sixty-one dislocations after cemented total hip arthroplasty, with a mean follow-up period of 8 years after dislocation, were reviewed with the aim of establishing the prognosis. There were 84% single and 16% recurrent dislocations. Closed reduction was successful in 81% of cases. Thirty-seven percent of dislocations were early (within 5 weeks), 36% occurred in patients who had had previous surgery, and in 47% there was nonunion of the trochanter. There was a two-way interaction between these factors, and all factors were significant for recurrent dislocation. Twenty-six (16%) recurrent dislocations required surgery. The most common causes of recurrent dislocation demonstrated at operation were component malposition (58%) and failure of the abductor mechanism (42%). In total, 96% of cases were successfully treated.     

Total condylar knee arthroplasty: a long-term followup.

Between July 1977 and December 1983, 80 patients underwent 120 arthroplasties using a total condylar knee prostheses. Forty-one patients (68 knees) died and 13 patients were lost to followup. Twenty-six patients with 34 total condylar replacements were available for clinical followup. During the followup, 10 knees in nine patients (8.3%) from the overall 80 patients (120 knees) underwent revision; three (four knees) for aseptic loosening, one for periprosthetic fracture, three for infection, and two patients underwent revision for pain. Three revisions (three patients) occurred in the group of 26 patients available for followup. The average age of this group of patients at followup was 78 years (range, 53-94 years). There were 10 men and 16 women. Considering the high mean age of the patients in the series and patients' overall health status, the clinical results were extremely good. Kaplan-Meier analysis showed a survivorship of 91% at 23 years followup, considering revision as an end point. Although there have been several changes in total knee replacement designs, materials, and implantation techniques, the long-term outcome of the original total condylar knee prosthesis is excellent.     

后方关节囊修补预防全髋关节置换术后早期脱位

[目的]探讨加强修补后方软组织预防行后外侧切口首次人工全髋关节置换术后早期脱位的临床疗效和机理。[方法]回顾分析212例首次THA术中缝合后方关节囊与外旋短肌至臀中肌腱性部分的病例术中假体旋转活动度及术后早期脱位率，并与前期行关节囊完全切除的486例作对照分析。[结果]随访6个月～5a（平均3．7a），修补关节囊组仅2髋（0．9％）发生术后早期脱位；对照组发生脱位27髋（5．6％）。两组差异有显著意义（x^2=8．51，P〈0．005）。术中观察显示修补关节囊能够限制髋关节过度内旋20％～50％，阻止股骨头假体在髋臼内衬内的初始滑动。[结论]在假体安放正确基础上，加强修补后方关节囊能够有效预防行后外侧切口首次THA术后早期脱位，机理为关节囊修补后能限制髋关节过度内旋、阻止股骨头假体在髋臼内衬内的初始滑动，并提供了形成致密的假关节囊的生物学基础。     

Bipolar hip arthroplasty for recurrent dislocation after total hip arthroplasty. A report of three cases.

Recurrent dislocation after total hip arthroplasty is often a difficult complication to manage. Bipolar prostheses may be useful in these cases because motion can occur at two bearing surfaces and thus permit the greater range of motion necessary to dislodge the head from the acetabulum. The bipolar head is also larger than a conventional total hip femoral component, so a greater volume must be displaced from the acetabulum for dislocation to occur. Three patients with recurrent dislocation of a total hip prosthesis were successfully treated by conversion to bipolar devices after failure of multiple surgical procedures and treatment even with braces.     

Prevention of thrombosis after hip arthroplasty

A prospective randomized study involving 101 patients undergoing total hip replacement was performed to find out whether prophylactic anticoagulation starting 4 days before the operation was more effective than starting on the eve of the operation. The postoperative level of anticoagulation was set at an INR of 2.1. There was no difference between the two groups in the incidence of proximal localized deep venous thrombosis. Blood loss did not depend on the level of peroperative anticoagulation. There were no postoperative hemorrhagic complications. No fatal pulmonary embolism occurred during the study. After discontinuation of the oral anticoagulants because of a negative venogram, nonfatal pulmonary embolism occurred in 3 out of 55 patients. A plea is made for low-dose anticoagulation for 3 months after total hip arthroplasty.     

Prevention of dislocation of total hip arthroplasty: the dual mobility cup

The concept of dual mobility cup has been developed to associate the advantages of the low friction total hip arthroplasty with those of large femoral head diameter, with the goal of preventing the dislocations. In this study, 100 primary THA and 34 revision THA with the use of dual mobility cup were analyzed clinically and radiological over a period of fellow up of ten years. It appears that the dual mobility cup is effective against dislocation. Any concerns regarding the survival of this type of prosthesis can be relativized. Literature datas indicate that mean total volumetric wear is of the same order as that reported for Charnley prosthesis with a head of 22,2 mm. However, uncertainty regarding the problem of intraprosthetic dislocation did persist.     

髋关节置换术后假体脱位的预防

查阅近年来关于全髋关节置换术后假体脱位的原因和预防措施研究的国内外相关文献,进行回顾及综合分析.术前对病人做详细的评估、选择合适的假体;术中提高假体位置安放的准确性、术后避免容易导致脱位的活动范围可以减少术后假体脱位的发生率.通过详细的术前、术中和术后处理可以降低术后假体脱位的发生率.     

全髋关节置换术后早期脱位研究进展

髋关节脱位是全髋关节置换(THA)后仅次于假体松动的主要并发症之一,多发生于术后早期(3个月内).尽管其发生已大大减少,但仍是影响THA疗效的早期并发症之一,对患者的精神和身体打击很大,如何防治一直是关注的焦点.该文就近年来THA后早期脱位研究进展作一综述.     

Locked inferior fracture dislocation after total hip arthroplasty

Acetabular fracture in conjunction with dislocation after total hip arthroplasty is a rarely reported event. We describe such a case with a unique fracture dislocation pattern, whereby the prosthetic femoral component dislocated inferiorly, fracturing the pelvis, and was locked in this position. The patient was treated with closed reduction under anesthesia and the fracture healed without further surgical intervention. However, she has experienced subsequent instability episodes and we have recommended revision surgery.     

人工全髋关节置换术后的并发症预防

正全髋关节置换术(total hip arthroplasty,THA)是20世纪最成熟的外科手术之一,国外起于40年代;50年代由我科范国声教授开展全国首例Judet股骨头置换术~([1]),开创了我国的髋关节置换术先河~([2])。经过了半个多世纪的发展,全髋关节置换术已经取得了良好的效果并有了长足的发展,2015年据不完全资料统计我国全髋关节置换术45～55万,且以每年25%～30%的速度递增~([3])。目前全髋     

全髋关节置换术后脱位的原因分析及处理

[目的]探讨全髋关节置换术后发生脱位的原因、处理及预防方法.[方法]自1996～2004年在本院行全髋关节置换患者共850例,发生置换术后脱位7例,其中男4例,女3例;平均年龄67岁;通过对术前病史、手术入路、术后脱位的时间以及发生脱位的方向进行回顾性研究以探讨脱位的原因、处理以及如何预防.[结果]本组发生全髋关节置换术后脱位7例,其中5例(5/7)为初次全髋关节置换术后脱位,2例(2/7)为翻修手术后脱位;4例(4/7)有既往髋部手术史;1例有脑部手术后精神异常,不配合治疗;脱位方向均为前脱位;所有患者均采用正外侧入路即改良Hardinge入路.髋臼假体外展角2例(2/7)大于55°.发生脱位时间自术后当天至术后27个月,其中5例发生于术后3个月以内.所有7例患者在脱位后均首先给以麻醉下闭合复位、下肢皮牵引6周治疗,其中6例患者获得稳定并未再复发性脱位;1例患者在复位后3个月内又连续2次脱位,并在复位过程中发生髋臼松动,给以手术翻修髋臼调整外展角后获得稳定.[结论]导致全髋关节置换术后脱位的危险因素主要包括髋部手术史、术后患者不能严格按照医嘱进行康复训练、手术人路以及假体位置不良等.对于大多数脱位患者而言,闭合复位以及皮牵引6周是有效的治疗方法,对于复发性脱位的患者在分析脱位原因后可通过翻修手术获得髋关节的稳定.     

Hospital cost of dislocation after primary total hip arthroplasty

BACKGROUND: The treatment of dislocation following primary total hip arthroplasty usually requires the use of expensive hospital resources and sometimes requires revision surgery. The hospital costs associated with treating this complication have not been previously analyzed, to our knowledge. The purpose of this study was to assess the financial impact of treating dislocations at our institution. METHODS: Between 1997 and 2001, 3671 patients underwent a total of 4054 consecutive primary total hip arthroplasties at our institution. The patients were prospectively followed at regular intervals, and their follow-up data were recorded in an institutional total joint registry. Ninety-nine hips (2.4%) in ninety-nine patients dislocated. The costs to our institution to treat these dislocations were evaluated by determining the cost of each treatment episode required to reestablish hip stability and were expressed as the percent increase in cost compared with that of an uncomplicated primary total hip replacement. RESULTS: Of the ninety-nine hips that dislocated, sixty-two (63%) remained stable after one or more closed reductions and thirty-seven (37%) ultimately required revision surgery. The hospital cost of each closed reduction episode represented 19% of the hospital cost of an uncomplicated total hip replacement. When revision surgery was eventually needed, the average hospital costs of one or more closed reductions and the subsequent revisions represented 148% of the hospital cost of an uncomplicated primary total hip replacement. CONCLUSIONS: Dislocation after primary hip replacement continues to be a prevalent and costly complication that diminishes the cost-effectiveness of an otherwise very successful surgical procedure.     

Traumatic hip dislocation in children. Long-term followup of 42 patients

To assess the impact of traumatic hip dislocations in the skeletally immature patient, 42 children younger than 16 years of age (average age, 9 years 10 months) who were treated at the authors' institution were studied. Data were collected from charts and radiographs and by completion of questionnaires. The average followup after injury was 10 years 1 month. The majority of dislocations (64%) were attributable to low energy injuries. Ipsilateral fractures about the hip occurred in 17% of patients. Avascular necrosis of the femoral head developed in 12% of patients, with the amount of time spent dislocated being the only statistically proven risk factor. Patients whose reduction was delayed greater than 6 hours had a 20 times higher risk of having avascular necrosis develop compared with patients whose hips were reduced in 6 hours or less. The use of computed tomography for joint asymmetry of 3 mm or greater and omission of bone scan screening were supported by this study. Functional outcomes were very good in this series with 95% of patients suffering mild (usually weather related) or no pain and 95% of patients suffering mild pain (intermittently noticeable) or no limp. A large percentage of the patients (78%) continued to participate in high demand activities such as football, soccer, and basketball.     

Trochanteric advancement for recurrent dislocation after total hip arthroplasty

Twenty-one patients had trochanteric advancement after experiencing an average of 3.9 dislocations in a mean period of 46 weeks following total hip arthroplasty. Before trochanteric advancement was performed, component malposition and mechanical impingement were excluded as causes of dislocation. Radiographic measurements revealed that the trochanter was advanced an average of 16 +/- 7.7 mm (1 SD). Four patients, all with rheumatoid arthritis, had trochanteric migration greater than 1 cm. Seventeen of the 21 hips had no further dislocations following trochanteric advancement, with mean follow-up period of 2.7 years. Two patients dislocated because of extremes in hip position and had no further dislocations. Two patients dislocated who had trochanteric migration greater than 1 cm. Only one patients with a technically satisfactory trochanteric advancement continued to dislocate repeatedly. In patients without component malposition or obvious sources of impingement, trochanteric advancement is an effective and safe procedure for prevention of recurrent dislocations after total hip arthroplasty.