Cementless total hip arthroplasty using an autograft of the femoral head for marked acetabular dysplasia: case series

PURPOSE: To assess the short-term outcome of cementless total hip arthroplasty involving an autograft of the femoral head in Japanese patients. METHODS: Cementless total hip arthroplasty with autogenous bone block grafting was performed on 18 hips in 15 patients with marked acetabular dysplasia. The resected femoral head was used as a graft for the superior-lateral region of the true acetabulum. Clinical outcome was correlated with the placement of the acetabular component, as revealed in radiographs. RESULTS: The 13 women and 2 men had a mean age of 60.2 years (range, 37.0-73.0 years) at primary surgery and a mean follow-up duration of 3.3 years (range, 2.0-5.3 years). According to the classification of Crowe, 4 hips were in group I, 3 were in group II, one in group III, and 10 in group IV. The mean Harris Hip Score preoperatively was 45.7 (range, 19-69) and that at follow-up was 82.5 (range, 44-100). All 15 cases showed a good clinical outcome. There were no major intra-operative complications in this series. The grafted bones united in all patients. Two patients need surgical revision because the lateral insertion of the acetabular component resulted in loosening of it. CONCLUSION: Medial insertion of the acetabular component provides satisfactory short-term outcomes. Lateral insertion of the acetabular component during total hip arthroplasty should be avoided in patients with marked acetabular dysplasia.     

髋关节发育不良的严重程度与骨水泥型全髋关节置换术后髋臼假体松动的相关性

目的探讨在骨水泥型全髋关节置换术髋臼假体的术后生存率和髋关节发育不良（development dysplasia of the hip,DDH）严重程度的相关性。方法应用骨水泥型全髋关节置换术治疗DDH合并创伤性髋关节炎患者92例103髋,女85例96髋,男7例7髋;年龄39～78岁,平均47．2岁。根据Crowe分级：42例46髋为Ⅰ度,21例24髋为Ⅱ度,16例18髋为Ⅲ度,13例15髋为Ⅳ度。49例56髋采用改良Gibson人路,43例47髋经直接外侧I-Iar-dinge人路。46例48髋使用自体股骨头进行髋臼骨移植,所有移植的骨块均用松质骨螺钉或Kirschner钢丝固定于髋臼上。进行骨移植的适应证主要是髋臼组成部分的上方未取得足够骨覆盖。结果62例76髋获得随访,随访时间2～19年,平均98个月。将因无菌性松脱而行髋臼翻修作为观察终点,10年随访髋臼假体生存率为86．8％～94．4％,平均90．6％;18年随访生存率为53．9％～72．O％,平均63．0％。结论随着髋臼发育不良严重程度的加重,随访年后骨水泥型髋臼假体有更高的失败率。     

Total hip replacement with the CLS expansion shell and a structural femoral head autograft for patients with congenital hip disease

BACKGROUND: Reconstruction of a dysplastic acetabulum in a patient with osteoarthritis of the hip may be accomplished with a variety of surgical techniques. The aim of our study was to assess the outcomes of total hip replacement with the uncemented CLS expansion shell and a structural femoral head autograft to augment the deficient acetabulum in patients with osteoarthritis secondary to congenital hip disease. METHODS: Between 1990 and 1994, we used a CLS expansion shell with a structural femoral head autograft in forty-three consecutive patients (forty-three hips) with osteoarthritis secondary to congenital hip disease. The ratio of male to female patients was 5:38, and the mean age of the patients was forty-eight years. According to the preoperative radiographic assessment, the dysplasia was categorized as Crowe type I in six patients, Crowe type II in thirty-one patients, and Crowe type III and type IV in three patients each. No patient was lost to follow-up. The mean duration of follow-up was 120 months. Plain radiographs were made immediately after surgery and at the latest follow-up evaluation. Clinical outcomes were determined with use of the Harris hip score and the Merle d'Aubigné and Postel score, and a radiographic analysis was performed. RESULTS: Postoperatively, the mean Harris hip score had improved 58 points for patients with Crowe type-I and II dysplasia, 47 points for patients with Crowe type-III dysplasia, and 46 points for patients with Crowe type-IV dysplasia (p < 0.05 for all). At the latest follow-up examination, the mean Harris hip score for all patients was 92.6 points. The mean Merle d'Aubigne and Postel score was 8.3 points preoperatively and 15.8 points at the time of the latest follow-up. The mean coverage of the shell by the graft immediately after surgery was 32.2%. Osteointegration of the CLS expansion shell was evident radiographically in all forty-three hips at the latest follow-up evaluation. There were no failures of the bone grafts. Clinical survival of the CLS expansion shell with a structural femoral head autograft was 100% at a mean of ten years after surgery. The rate of survival of the shell, with radiographic signs of loosening as the end point, was 88.2% at ten years. CONCLUSIONS: The CLS uncemented expansion shell, when used with a structural femoral head autograft, provides a reliable reconstruction, augments deficient acetabular bone stock, and allows placement of the socket at or close to the anatomic center of hip rotation in patients undergoing total hip arthroplasty to treat the sequelae of congenital hip disease.     

Total hip arthroplasty with bulk femoral head autograft for acetabular reconstruction in developmental dysplasia of the hip

BACKGROUND: The long-term results of total hip arthroplasty performed with cement and use of a bulk autograft for acetabular reconstruction in patients with developmental dysplasia of the hip have varied considerably. We evaluated the results of total hip arthroplasties performed with acetabular bulk autograft to identify the factors that influence the results of this procedure. METHODS: Acetabular roof defects secondary to developmental dysplasia of the hip were reconstructed with a bulk femoral head autograft at the time of total hip arthroplasties performed with use of the Charnley technique and prosthesis. Thirty-seven hips in thirty patients (mean age at the time of the operation, fifty-seven years) were followed for ten to twenty-six years (mean, nineteen years). The Crowe classification of hip subluxation or dislocation was Group II for sixteen hips, Group III for seventeen, and Group IV for four. RESULTS: Coverage of the socket by the graft ranged from 5% to 49% (mean, 33%). Twenty-nine sockets were located within the true acetabulum, and eight were placed more proximally. At the time of the latest follow-up, all of the patients had an excellent clinical result, all of the grafts had united, and no hip had radiographic evidence of failure of the fixation. CONCLUSIONS: We found that total hip arthroplasty performed with cement and use of a bulk autograft to reconstruct an acetabulum with severe bone deficiency secondary to developmental dysplasia of the hip can provide long-term success in patients forty-eight years of age and older when coverage of the socket by the graft does not exceed 50%. When it is not possible to achieve >50% coverage of the socket by the ilium at the level of the true acetabulum, more proximal placement of the socket to obtain adequate coverage is recommended.     

Long-term results of bulk femoral head autograft in cementless THA for developmental hip dysplasia

We evaluated the fate of bulk femoral head autograft in cementless total hip arthroplasty (THA) for developmental hip dysplasia. Of 87 hips (80 patients) studied, 37 hips (32 patients) were available for follow-up at a mean of 18.5 years (range, 15-24 years) postoperatively. The mean age of these 32 patients at the index procedure was 53.8 years (range, 40-65 years). The initial diagnosis was osteoarthritis in all 32 patients. The degree of acetabular dysplasia according to Crowe classification was type I in 18 hips (48.6%), type II in 14 (37.8%), type III in 5 (13.5%). The mean percentage of horizontal coverage of the acetabular components with graft bone was 34% (range, 25%-45%). Trabecular bridging across the graft-host interface was seen at a mean of 4 months (range, 2-6 months) postoperatively. Trabecular reorientation of the grafted bone was seen in all hips at a mean of 27 months (range, 12-36 months) postoperatively. There was no evidence of collapse and bony resorption of the grafted bone in the weight-bearing portion. Acetabular component fixation was stable in all hips at final follow-up. Of the 37 hips (32 patients), 2 acetabular components required revision: 1 for a late postoperative deep infection and 1 for dissociation of the polyethylene liner. The survival rate was 94.5% (95% confidence interval, 91.3-96.5) for the acetabular component at 18.5 years of follow-up. This study found that bulk femoral head autograft in cementless THA for developmental hip dysplasia produces excellent long-term results.     

Long-term survival of the acetabular component after total hip arthroplasty with cement in patients with developmental dysplasia of the hip

BACKGROUND: Total hip arthroplasty with cement remains a difficult procedure in patients with osteoarthritis secondary to developmental dysplasia of the hip as it is associated with high rates of aseptic loosening of the acetabular component. The purpose of the present study was to evaluate the rate of revision of the acetabular component in this group of patients and the variables that are associated with it. METHODS: We retrospectively reviewed the records and radiographs of 292 hips in 206 patients who had undergone total hip arthroplasty with cement for the treatment of osteoarthritis secondary to developmental dysplasia of the hip. The average age of the patients at the time of the index procedure was 42.6 years, and the average duration of follow-up was 15.7 years (range, 2.2 to 31.2 years). Fourteen patients were lost to follow-up, and seven patients died from causes unrelated to surgery. A 22.25-mm head was used in all cases, and bone-grafting of the acetabulum was performed in forty-eight hips. Survival of the acetabular component was calculated with revision for aseptic loosening as the end point. Individual survival rates based on age, component type, previous surgery, and annual polyethylene wear also were calculated. RESULTS: The most common reason for revision was aseptic loosening of the acetabular component, which led to 87.2% of the revision procedures. The overall rate of survival of the acetabular component was 90.6% at ten years and 63% at twenty years. A higher rate of acetabular revision was noted in association with previous acetabular surgery, the offset-bore cup, younger age, and accelerated polyethylene wear (p < 0.05 for all comparisons). CONCLUSIONS: Aseptic loosening of the acetabular component affects the longevity of total hip replacements in patients with osteoarthritis secondary to developmental dysplasia of the hip. The present study identified the risk factors associated with the long-term survival of the acetabular component in this group of patients.     

Charnley low-friction arthroplasty with an autograft of the femoral head for developmental dysplasia of the hip. The 10- to 15-year results

Between 1983 and 1988 we carried out 45 Charnley low-friction arthroplasties with autografts from the femoral head in 41 patients for developmental dysplasia of the hip. The preoperative radiographs were assessed for the severity of DDH according to the classifications of Crowe et al, Hartofilakidis et al and Sharp. The postoperative and follow-up radiographs were analysed for coverage of the socket by the graft, for loosening and for the outcome of the fixation of the bone graft. Two patients died (two hips) at four and seven years after THR from causes unrelated to the surgery and were excluded from the final radiological analysis. The mean age of the patients at the time of operation was 46 years 3 months. The autograft of the femoral head covered a mean 26% (16 to 35) of the acetabular component. All the grafts united. Some degree of resorption of the bone graft occurred in 27 patients, and always involved the lateral part of the graft, which was beyond the margin of the socket. After a mean follow-up of 11 years there had been no revisions and 38 patients had no pain or only slight discomfort. One socket migrated and four others were fully demarcated. Our findings indicate that the Charnley LFA with an autograft of the femoral head for DDH remains successful at a follow-up of 15 years.     

全髋关节置换术治疗成人髋关节发育不良的髋臼重建

目的探讨全髋关节置换术治疗成人髋关节发育不良（DDH）时不同方式髋臼重建对疗效的影响。方法 2000年1月至2007年10月,36例（44髋）先天性髋臼发育不良患者进行了全髋关节置换。年龄42～65岁,平均48岁。术前Harris评分平均为49.9分,双下肢长度差异平均为1.8 cm,髋关节平均活动度：屈曲59.6°,外展21.6°,内收13.9°,外旋10°,内旋8.2°。术中臼杯均安装于真臼处,髋臼内移14髋,髋臼内陷成形术18髋,自体股骨头结构性植骨12髋。髋臼侧均选用非骨水泥型假体。疗效评价：根据Harris评分分为优、良、可、差四级。结果所有患者均获得随访,随访时间1.8～9.2年,平均5.1年。平均Harris评分由术前的49.9分恢复到术后的90.1分,两者比较有统计学差异（P〈0.01,t=28.807）,其中评定为优23髋、良17髋、可4髋,术后优良率达90.9%。术后髋关节平均活动度：屈曲105°,外展35°,内收15.8°,外旋45°,内旋15°。本组病例无肺栓塞、深静脉血栓形成、感染等并发症发生。X线检查示假体无松动移位,无翻修病例。结论全髋关节置换术治疗成人髋臼发育不良采用恰当的髋臼重建结合非骨水泥型髋臼假体可获得满意中远期疗效。     

Impaction grafting for acetabular deficiency in total hip arthroplasty for developmental hip dysplasia

The pathological anatomy in neglected developmental dysplasia of the hip often demands some sort of reconstructive surgery to augment the acetabular bone stock during total hip arthroplasty. We have reviewed 11 hips in 10 patients with osteoarthritis secondary to developmental hip dysplasia who underwent cemented total hip arthroplasty using impaction grafting of the acetabulum with a morselized femoral head autograft, to bring the socket down to the anatomical hip center. The mean age at the index procedure was 43.4 years (ranging from 29 to 60 years) and the mean follow-up period was 3.8 years (ranging from 2 to 7 years). Postoperative functional evaluation according to the Merle d'Aubigné and Postel score modified by Charnley revealed very satisfactory results. Radiographic review showed incorporation of all grafts. One socket is radiographically loose. No major complications have been encountered. There have been no reoperations. We believe that acetabular impaction grafting is a valuable alternative in dealing with osteoarthritic hips secondary to developmental hip dysplasia.     

骨盆相关数据测量对髋臼发育不良髋臼定位的临床意义

[目的]通过对中国南方50例单侧髋关节置换患者的全骨盆X线片相关数据的测量与分析,来验证JFCrowe在"Totalf hip replacement in congenital dislocation and dysplasia of the hip"(J.Bone Joint Surg.Am,1979,61:15-23)一文中提到的"股骨头颈交点与股骨头上缘的垂直距离跟坐骨结节下缘与髂骨最高点的垂直距离的比率是20%"的准确性,进而提出国人髋臼发育不良真臼的正确定位。目前国内外尚无新的报道。[方法]测量股骨头颈交点与股骨头上缘的垂直距离(BC),测量坐骨结节下缘与髂骨最高点的垂直距离(AD),计算BC与AD的比率。[结果]50例样本平均值为20.2%,与Crowe观察的结果吻合,其中女性为19.5%,男性为21.3%。[结论]对于髋臼发育不良或者髋关节发育不良的患者,对于真臼的定位可以按照这个比率进行正确的定位。     

Inter- and intraobserver reliability of the Crowe and Hartofilakidis classifications in the assessment of developmental dysplasia of the hip in adult patients

Background

The purpose of this study is to investigate the inter- and intraobserver reliability of Crowe and Hartofilakidis classifications in the assessment of developmental dysplasia of the hip in adult patients.

Materials and methods

Two consultant orthopedic surgeons classified 141 dysplastic hips on 103 standard anterior–posterior pelvis radiographs according to the Crowe and Hartofilakidis classifications. Assessments were performed in random order by each observer on two separate occasions, at least 4?weeks apart. Kappa statistics were used to establish a relative level of agreement between observers for the two readings and between separate readings by the same observer.

Results

At the first readings, interobserver reliability analysis revealed kappa coefficient of 0.71 for the Crowe classification and 0.54 for the Hartofilakidis classification. At the second reading, the kappa coefficient was 0.72 for the Crowe classification and 0.75 for the Hartofilakidis classification. Intraobserver reliability analysis revealed kappa coefficients of 0.71 for the Crowe and 0.80 for the Hartofilakidis classification for observer A, and 0.76 and 0.70 for observer B.

Conclusions

In conclusion, we have found substantial inter- and intraobserver agreement for Crowe classification and substantial to moderate agreement for Hartofilakidis classification in this study. Both classification systems assess the different aspects of developmental dysplasia of hip in adults. Each system has advantages and disadvantages. We suggest using both of these classifications together to increase the accuracy.     

The Artek cup for total hip replacement of dysplastic hip joints

Background One specific difficulty in total hip replacement for developmental dysplasia of the hip is a shallow acetabulum with a short anteroposterior diameter. In a prospective cohort study we investigated the short-term results of the Artek cup, designed with a shallow outline and a height-reduced metal inlay for a large size 38 mm metal head, in a group of female patients with mild dysplasia of the hip.Methods Fourteen consecutive patients with 17 dysplastic hip joints were included in the study. Their average age was 42 years. Fourteen hips had dysplasia Crowe grade I; 3 hips had dysplasia Crowe grade II. The femoral head centre was localized according to Pagnano in zone 1 in 3 cases, in zone 3 in 6 cases, and in zone 4 in 8 cases. The Harris hip score was 49 points (range 30–68 points).Results Mean follow-up was 20 months (range 14–24 months). The Harris hip score improved to a mean of 91 points (range 78–98 points). The postoperative radiographic measurements showed an inclination angle of 52.1° (range 43–66°). The femoral head centre was in Pagnano zone 1 in 13 cases, in zone 2 in 1 case, in zone 3 in 1 case, and in zone 4 in 2 cases. The mean postoperative deviation from the approximative rotational centre was 0.17 mm (range -15 to 13 cm) in the superior direction and 5.3 mm (range -5 to 17 mm) in the lateral direction.Conclusion In a small series of 17 implantations, stable press-fit fixation without screws or bone grafting was achieved despite acetabular defects. The complication rates were high. Inclination angles up to 54° were not correlated with complications. Inclination angles of 60° and more led to subtotal or complete dislocation. Mid-term results are still to follow concerning wear, dislocation rate, loosening and revision.An erratum to this article can be found at     

Crowe IV 型髋关节发育不良全髋关节置换术前计算机辅助设计

 目的 探索采用计算机辅助技术, 对接受全髋关节置换(total hip arthroplasty, THA)的 Crowe IV型髋关节发育不良患者进行术前评估, 确定髋臼大小、骨缺损程度, 并在此基础上辅助手术设 计、假体选择及骨缺损修复。 方法2011 年3 月至10 月, 共10 例(13 髋)Crowe IV型高位脱位髋关节发 育不良患者接受THA 治疗。患者均为女性;年龄32~74 岁, 平均42 岁。所有患者术前行髋关节三维CT 扫描, 然后将扫描数据输入SuperImage 软件重建骨盆及髋臼。重建后在不同角度精确评估真臼位置, 测 量真臼大小及前后柱厚度, 评估骨缺损程度;将髋臼试模、骨缺损修复材料(钽金属垫块)按1颐1 大小扫 描输入计算机系统, 进行术前模拟安放, 确定髋臼假体大小、安放位置;髋臼假体安放后评估遗留的骨缺 损, 确定骨缺损修复材料, 进行骨缺损修复模拟测试。 结果 9 例(12 髋)术中实际安放髋臼假体型号与 术前计算机辅助设计一致, 1 例(1髋)假体型号较术前设计大一号。所有患者髋臼安放位置与术前计划 一致, 均安放于真臼。髋臼骨缺损修复按术前设计:4 髋因髋臼顶部骨缺损明显(臼顶部骨性覆盖 < 70%), 采用钽金属垫块修复骨缺损, 以增强髋臼的稳定性;7 髋采用Harris 法自体股骨头植骨修复骨缺 损;2 髋髋臼杯植入后臼顶覆盖可, 术中未植骨。 结论 对Crowe IV型髋关节发育不良者行计算机辅助 下THA术前设计, 有助于术前精确评估真臼发育情况、大小及髋臼骨缺损, 提高手术治疗精确性。     

Efficacy of alumina ceramic heads for cemented total hip arthroplasty.

Fifty-seven cemented total hip arthroplasties (THAs) were reviewed in cases of osteoarthrosis secondary to congenital dysplasia or dislocation. The bearing surface of the prosthesis used in this series consists of a polyethylene acetabular component on an alumina ceramic head. All acetabular components were positioned at the same level as the original acetabulum, and an autologous femoral head graft was performed for 18 hips. The follow-up period ranged from five to eight years, averaging six years two months. The latest survey showed excellent and good results for 53 hips (92.9%). Four acetabular components (7%) and two femoral components (3.5%) showed roentgenographic evidence of loosening. Only one hip (1.8%) had to be treated with revision surgery for femoral component loosening. None of the cases suffered a broken ceramic head. The use of a total hip prosthesis with an alumina ceramic head in THA is likely to lead to excellent results for patients with osteoarthrosis of the hip.     

关节置换加自体股骨头移植治疗髋关节发育不良

目的：探讨关节置换加自体股骨头移植治疗髋关节发育不良。方法：自1995-2000年用关节置换加自体股骨头移植治疗髋关节发育不良40例(36例病人)，术前放射学评价髋关节发育不良的严重程度，术后随访分析移植物对假体的覆盖率、松动及移植物的固定情况。本组病人平均年龄44岁。术后移植的股骨头覆盖平均占髋臼28％。结果：随访2～7年，所有骨移植均融合，22例移植骨有部分吸收，但均在覆盖假体外上边缘，假体无移位。全部病例无疼痛或仅有轻度不适。结论：关节置换加自体股骨头移植是治疗髋臼不良的有效方法之一。     

髋关节发育不良的髋臼重建

目的　总结采用全髋关节置换术治疗髋关节发育不良继发骨关节炎和功能障碍的经验。方法　 1998年 4月至 2 0 0 2年 4月 ,对 96例 112髋 (双侧 16例 )成人髋关节发育不良继发骨关节炎患者进行了全髋关节置换术。其中 ,半脱位 73髋 ,低位脱位 18髋 ,高位脱位 2 1髋。髋臼侧均采用真臼位置重建 ,其中骨水泥固定 16髋 ,非骨水泥固定 96髋 ,植骨 11髋 ;采用常规置换 83髋 ;磨削加深髋臼后 ,安置小号髋臼假体 2 7髋 ;髋臼外上缘自体股骨头植骨加深髋臼后 ,安置小号髋臼假体 2髋。结果　患者术后伤口均一期愈合 ,未发生感染或血管神经损伤 ,患肢长度平均延长 1 7cm。随访 85例 98髋 ,平均随访 3 5年 ,关节疼痛缓解 ,活动功能满意 ,Harris评分由术前的平均 33 9分恢复到平均 89 3分 ,无假体松动和翻修病例。X线片显示 ,关节假体位置正常 ,人工髋臼的平均外展角4 4° ,宿主骨对臼杯的平均覆盖率为 96 6 % ,金属臼杯与宿主髋臼之间未见透光线 ;11髋髋臼侧植骨病例中 ,植骨块与宿主骨愈合良好 ,未见骨吸收现象。结论　全髋关节置换术是治疗髋关节发育不良继发骨关节炎患者的有效方法 ;术前应充分考虑髋关节发育不良的原发及继发性病理改变 ,尽可能在真臼位置重建髋臼     

Autophor cementless total hip arthroplasty for osteoarthrosis secondary to congenital hip dysplasia

The authors present a consecutive series of 38 arthroplasties for osteoarthrosis secondary to hip dysplasia. All arthroplasties were performed by a single surgeon using Mittelmeier II (Autophor, Osteo AG, Selzach, Switzerland) ceramic cementless components. Crowe grades of subluxation were 60% grade I, 16% grade II, 12% grade III, and 12% grade IV. In all cases, the acetabular component was seated in the true acetabulum. The mean follow-up period was 75 months (range, 40–122 months). By the time of review, six hips (16%) had required revision for aseptic loosening, mainly of the femoral component. Good or excellent results were achieved in only 63% of the patients. In the group of surviving arthroplasties, the median Charnley hip scores before surgery were: pain, 2; movement, 3; and walking, 3. After surgery, the scores were: pain, 5; movement, 5; and walking, 6. All improvements were significant. The mean postoperative Harris hip score was 84. Poor scores were associated with contralateral hip disease (2 cases) and spina bifida (2 cases), significantly affecting function. The Autophor prosthesis can produce satisfactory results in some of these young patients with hip dysplasia. However, femoral loosening is a major problem and because of this, the authors have since changed to a newer stem design.     

Removal of acetabular bone in resurfacing arthroplasty of the hip: a comparison with hybrid total hip arthroplasty

Resurfacing arthroplasty of the hip is being performed more frequently in the United Kingdom. The majority of these patients are younger than 55 years of age, and in this group the key benefits include conservation of femoral bone stock and the potential reduction in the rate of dislocation afforded by the larger resurfacing head. Early aseptic loosening is well recognised in patients younger than 55 years of age, and proponents of resurfacing believe that the improved wear characteristics of the metal-on-metal bearing may improve the long-term survival of this implant. There has been some concern, however, that resurfacing may not be conservative of acetabular bone.We compared a series of 33 consecutive patients who had a hybrid total hip arthroplasty with an uncemented acetabular component and a cemented femoral implant, with 35 patients undergoing a Birmingham hip resurfacing arthroplasty. We compared the diameter of the implanted acetabulum in both groups and, because they were not directly comparable, we corrected for patient size by measuring the diameter of the contralateral femoral head. The data were analysed using unpaired t-tests and analysis of covariance.There was a significantly larger acetabulum in the Birmingham arthroplasty group (mean diameter 56.6 mm vs 52.0 mm; p < 0.001). However, this group had a significantly larger femoral head diameter on the contralateral side (p = 0.03). Analysis of covariance revealed a significant difference between the mean size of the acetabular component implanted in the two operations. The greatest difference in the size of acetabulum was in those patients with a larger diameter of the femoral head. This study shows that more bone is removed from the acetabulum in hip resurfacing than during hybrid total hip arthroplasty, a difference which is most marked in larger patients.     

成人髋关节发育不良不同Crowe分型的三维CT影像学特征

 目的 通过三维CT重建分析成人髋关节发育不良不同Crowe分型之间髋臼形态的演变规律。方法 2010年6月至2013年1月收治成人髋关节发育不良患者62例68髋,男6例8髋,女56例60髋;年龄47~59岁,平均（53.7±5.8）岁。CroweⅠ型14例17髋,Ⅱ型17例17髋,Ⅲ型15例17髋,Ⅳ型16例17髋。行标准髋关节CT扫描及三维重建。在侧位三维图像上标记Harris窝,确定髋臼旋转中心,利用十字坐标轴确定髋臼旋转中心的冠状面和横断面位置;在正位三维图像上利用Ranwant三角确定髋臼旋转中心的矢状面位置;在髋臼水平重建图像上确定髋臼旋转中心。观察髋臼前后缘增生及髋臼前后柱发育不良程度,测量并比较不同Crowe分型患者的髋臼前倾角、前覆盖角、后覆盖角和内壁宽度。结果 随Crowe分型增加,髋臼前倾角逐渐加大,两者呈正相关,除CroweⅠ型和Ⅱ型组间外,其余组间差异有统计学意义;髋臼前覆盖角逐渐减小,两者呈负相关,各组间差异均有统计学意义,CroweⅢ、Ⅳ型组平均值小于50°;髋臼后覆盖角逐渐减小,两者呈负相关,各组间差异均有统计学意义, CroweⅢ、Ⅳ型组平均值小于90° ;髋臼内壁宽度逐渐增加,两者呈正相关,各组间差异均有统计学意义。结论 不同Crowe分型成人髋关节发育不良的髋臼形态变化存在一定的演变规律。对CroweⅠ型和Ⅱ型髋臼的重建可充分利用髋臼前后柱骨量,对CroweⅢ、Ⅳ型髋臼的重建可适度上移和（或）内移髋臼中心。     

Cemented total hip arthroplasty with acetabular bone graft for developmental dysplasia. Long-term results and survivorship analysis

Although the technique of autogenous acetabular bone grafting has been widely used to augment containment of the acetabulum in total hip arthroplasty (THA) for developmental dysplasia, the role of this technique in improving long-term results remains controversial. We present the long-term results of cemented THA with acetabular bone grafting in 112 patients (133 hips) in order to clarify the factors which affect the outcome. The mean follow-up was for 12.3 years (8 to 24). Kaplan-Meier survivorship analysis predicted a rate of survival of the acetabular component at 15 years of 96% (95% confidence interval (CI) 92 to 99) with revision for aseptic loosening as the endpoint, and of 75% (95% CI 65 to 85) when radiological loosening was used. Parametric survivorship analysis using the Cox proportional-hazards model indicated that trochanteric nonunion, lateral placement of the socket, and delayed trabecular reorientation of the bone graft were risk factors for loosening of the acetabular component. Our findings have shown that autologous acetabular bone grafting is of value for long-term success provided that the risk factors are reduced.