Alumina femoral head fracture in uncemented total hip arthroplasty with a ceramic sandwich cup

In total hip arthroplasty, insertion of a UHMWPE-coated ceramic sandwich liner dramatically reduces any risk related to the stiffness of the ceramic-ceramic coupling. We present a case of an alumina ceramic head fracture with a ceramic sandwich cup. The fracture occurred 16 months after the initial operation, without trauma. Impingement between the neck and posteroinferior portion of the liner rim had occurred. This was related to the traditional cross-legged sitting position of Koreans, which caused impingement between the neck and liner rim. Consequently, the taper became loose, and the resulting force bent the taper and fractured the head. We examined a peculiar case of ceramic femoral head fracture after implantation of an uncemented total hip arthroplasty with a ceramic sandwich cup and investigated the underlying cause.     

Ceramic acetabular liner fracture in total hip arthroplasty with a ceramic sandwich cup

In total hip arthroplasty, a modular acetabular component with a sandwich insertion (alumina ceramics/polyethylene/titanium) was proposed. The polyethylene layer might reduce the rigidity of the ceramics and prevent an impingement between the ceramic liner rim and the femoral neck. A case of an acetabular liner fracture of the ceramic sandwich cup was presented. The fracture occurred 1.4 years after the operation without trauma. Because the ceramic liner rim was hit by the head following the impingement between the neck and the polyethylene, the cause of the fracture might be the stress concentration at the rim of the ceramic liner, of which the thickness was only 4 mm. At revision surgery, the fractured ceramic liner was replaced with a polyethylene liner without inner ceramic liner.     

Conversion total hip arthroplasty: Primary or revision total hip arthroplasty

Total hip arthroplasty (THA) is an increasingly common procedure among elderly individuals. Although conversion THA is currently bundled in a diagnosis related group (DRG) with primary THA, there is a lack of literature supporting this classification and it has yet to be identified whether conversion THA better resembles primary or revision THA. This editorial analyzed the intraoperative and postoperative factors and functional outcomes following conversion THA, primary THA, and revision THA to understand whether the characteristics of conversion THA resemble one procedure or the other, or are possibly somewhere in between. The analysis revealed that conversion THA requires more resources both intraoperatively and postoperatively than primary THA. Furthermore, patients undergoing conversion THA present with poorer functional outcomes in the long run. Patients undergoing conversion THA better resemble revision THA patients than primary THA patients. As such, patients undergoing conversion THA should not be likened to patients undergoing primary THA when determining risk stratification and reimbursement rates. Conversion THA procedures should be planned accordingly with proper anticipation of the greater needs both in the operating room, and for in-patient and follow-up care. We suggest that conversion THA be reclassified in the same DRG with revision THA as opposed to primary THA as a step towards better allocation of healthcare resources for conversion hip arthroplasties.     

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.     

Misinterpretation of cup anteversion in total hip arthroplasty using planar radiography

Introduction Anteroposterior pelvic radiographs are routinely used to monitor cup orientation in total hip arthroplasty (THA). Analysis of planar radiographs leads to a certain degree of measurement error for the cup anteversion (AV). With the current study, we wanted to clarify whether planar radiography can be used for accurate evaluation of the THA position.Materials and methods The postoperative orientation of pelvic implants in 42 patients was analyzed according to five documented mathematical algorithms using planar radiographs. Postoperative computed tomography (CT) pelvis scans were available for all patients. A CT-based navigation system was used to determine AV. Results The comparison showed that all five formulas presented substantial variations for the AV angle. Of these, Widmer’s algorithm presented the smallest difference compared to the CT. Misinterpretation of postoperative planar radiographs is a common problem in THA.Conclusion Planar radiographs are too imprecise for exact evaluation of the correct cup AV after THA. CT-based analysis may be necessary if exact values are required.     

Metal neck and liner impingement in ceramic bearing total hip arthroplasty

Although impingement between the neck of the metallic stem and the ceramic liner has been suspected to be the cause of ceramic liner failure in ceramic‐on‐ceramic total hip arthroplasty (THA), no report has directly demonstrated microscopic damage on ceramic liner. We performed 18 reoperations on 18 patients who had undergone third generation ceramic‐on‐ceramic THA. Considering impingement, 16 patients, who were reoperated more than 1 year after previous ceramic bearing THA, were evaluated. Retrieved alumina liners, showing evidence of impingement, were examined by means of visual inspection and scanning electron microscopy (SEM). Four of the 16 hips showed neck notching and black stained liners, evidence of metallic neck to ceramic impingement. Impinged alumina bearings had been implanted for an average of 62.5 months (range: 35–99 months) before reoperation. SEM of the black stained area demonstrated disruptive wear and loss of surface integrity. Furthermore, one liner had multiple microcracks, and its cross‐sectional SEM analysis revealed one microcrack propagating into the deep portion of the ceramic liner. Our observations suggest that metal neck‐to‐ceramic impingement in ceramic‐on‐ceramic THA can cause microcrack formation in ceramic liner. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:218–222, 2011     

螺旋臼全髋关节置换术治疗发育性髋关节发育不良

目的探讨使用螺旋臼假体治疗发育性髋关节发育不良（DDH）继发骨性关节炎患者的临床疗效。方法自2003年5月至2007年12月，使用Zweymaller螺旋臼假体治疗40例（43髋）DDH继发骨性关节炎患者，其中男6例（6髋），女34例（37髋），平均年龄47．6岁（22～70岁）；单侧37例，双侧3例；Crowe分型：Ⅰ级6例，Ⅱ级24例，Ⅲ级10例，Ⅳ级3例。平均随访24．6个月，术前Harris评分最高61分，最低22分，平均43．5分。结果所有患者术后疼痛基本消失，双下肢长度差异平均1．2cm，2例术后出现股神经损伤症状，术后6个月症状基本消失，Harris评分最高97分，最低62分，平均85．3分。结论使用Zweymtiller螺旋臼假体治疗DDH继发骨性关节炎的患者，可以达到良好的恢复关节功能的临床疗效，手术不需大块植骨和骨水泥，初期临床效果满意。     

Outcomes of dual-mobility acetabular cup for instability in primary and revision total hip arthroplasty

Background

The concept of a dual-mobility hip socket involves the standard femoral head component encased in a larger polyethylene liner, which in turn articulates inside a metal shell implanted in the native acetabulum. The aim of this study was to assess outcomes from using a Serf Novae^® Dual Mobility Acetabular cup (Orthodynamics Ltd, Gloucestershire, UK) to address the problem of instability in primary and revision total hip arthroplasty (THA).

Materials and methods

A retrospective review was carried out of all hip arthroplasties performed in a District General Hospital utilising the dual-mobility socket from January 2007 to December 2012. Clinical and radiological outcomes were analysed for 44 hips in 41 patients, comprising 20 primary and 24 revision THA. The average age of the study group was 70.8 years (range 56–84 years) for primary and 76.4 years (range 56–89 years) for revision arthroplasty. Among the primary THA, always performed for hip osteoarthritis or in presence of osteoarthritic changes, the reasons to choose a dual mobility cup were central nervous system problems such as Parkinson’s disease, stroke, dementia (10), hip fracture (5), failed hip fracture fixation (2), severe fixed hip deformity (2) and diffuse peripheral neuropathy (1). The indications for revisions were recurrent dislocation (17), aseptic loosening with abductor deficiency (4), failed hemiarthroplasty with abductor deficiency (2) and neglected dislocation (1).

Results

At a mean follow-up of 22 months (range 6–63 months), none of the hips had any dislocation, instability or infection and no further surgical intervention was required. Radiological assessment showed that one uncemented socket in a revision arthroplasty performed for recurrent dislocation had changed position, but was stable in the new position. The patient did not have complications from this and did not need any surgical intervention.

Conclusions

Even though postoperative hip stability depends on several factors other than design-related ones, our study shows promising early results for reducing the risk of instability in this challenging group of patients undergoing primary and revision hip arthroplasty.

Level of evidence

IV.     

Fracture of the ceramic head in total hip arthroplasty: Report of two cases

This article reports two cases of fracture of the ceramic head component in total cementless hip arthroplasty. There was no history of difficulty prior to the component fracture, neither during the operation nor during daily use, and in one of the patients, no history of trauma was observed.     

Five-year follow-up with a ceramic sandwich cup in total hip replacement

The results of the first 56 consecutive total hip replacements using a new cementless, sandwich (alumina-polyethylene-titanium) acetabular component are reported. From March 1994 to March 1995 we operated on 39 female and 17 male patients; their mean age was 62.8 years (range 32-85 years). The Harris Hip Score was used for clinical evaluation. X-rays were examined according to the DeLee and Charnley method. At an average follow up of 62.4 months, 51 patients had complete clinical and radiographic data. For them, we recorded a good clinical result (average HHS 90.6), and we could detect no acetabular radiolucencies on X-rays. At the 5-year follow-up the results of this ceramic acetabular cup are quite encouraging. As a matter of fact, although the clinical results are very similar to those reported by other authors with conventional ceramic-polyethylene coupling prosthesis, the absence of periacetabular radiolucency and socket migration could mean less debris formation, less acetabular wear and, consequently, a longer life of the implant.     

人工全髋置换不同类型臼临床疗效分析

目的比较人工髋关节置换不同类型臼治疗髋关节病损临床效果。方法对93例107髋分别采用压配型及螺旋型臼行人工关节置换。结果随访2～9年。按照Harris评分进行疗效对比分析。压配型1年后松动4例,行走时疼痛,螺旋臼组随访无松动。结论螺旋型臼侧假体具有设计合理、能够获得即刻稳定、适应证广泛、松动率低等优点。     

Spontaneous fracture of the ceramic ball in a ceramic—polyethylene total hip arthroplasty

Fractures of the ceramic ball in total hip arthroplasty are an uncommon cause of arthroplasty failure, and reports of this complication in ceramic-on-polyethylene total hip arthroplasty articulations are rare. Ball fractures have been reported in patients who were overweight, had high levels of activity, or had been injured. Other postulated contributory factors have included small ball diameter, defects in ceramic quality or manufacture, and errors in implantation of the arthroplasty. A case of a ceramic ball fracture in a ceramic and polyethylene articulation is reported, and the literature on such fractures is reviewed.     

初次人工全髋关节置换术中髋臼骨折的原因及处理

目的探讨初次行人工全髋关节置换术(total hip arthroplasty,THA)术中发生髋臼骨折的原因和处理方法。方法 2005年5月-2008年7月,9例9髋初次行THA患者术中发生髋臼骨折。男1例,女8例;年龄41～73岁,平均63.3岁。发育性髋关节发育不良4例,类风湿性关节炎2例,陈旧性股骨颈骨折1例,股骨头缺血性坏死1例,强直性脊柱炎1例。病程1～35年,平均19.5年。左髋3例,右髋6例。Harris评分为(40.4±2.9)分。患者均选择非骨水泥型假体。术中发生髋臼前壁骨折2例,后壁骨折6例,均属稳定型骨折,1例未作特殊处理,余7例给予3～4枚螺钉加强固定;后壁骨折伴后柱不全骨折1例,属不稳定型骨折,给予髋臼杯底植骨联合3枚螺钉固定。结果术后X线片检查示假体位置良好。切口均Ⅰ期愈合,无早期并发症发生。9例患者均获随访,随访时间1～4年,平均2年7个月。末次随访时Harris评分为(87.8±3.9)分,与术前比较差异有统计学意义(t=44.904,P=0.000)。X线片检查示,骨折均于术后8周达临床愈合;随访期间未发现髋臼假体周围透亮带及松动表现。结论初次行THA术前应仔细测量,术中充分显露,精细操作,避免暴力。非骨水泥型髋臼假体直径不应超过髋臼锉直径2 mm;对于骨质疏松患者,宜选用与髋臼锉直径相同的假体并用螺钉固定,或直接采用骨水泥型假体。一旦术中发生髋臼骨折,可根据骨折类型和假体稳定性选用增加螺钉固定或植骨配合多枚螺钉固定。     

Bilateral fractures of alumina ceramic heads in total hip arthroplasty and subsequent ceramic re-fracture after revisional arthroplasty in sandwich ceramic cup

A case of bilateral fractures of both ceramic heads in total hip arthroplasty and subsequent re-fracture of ceramic component after revisional surgery with ceramic sandwich cup exchange is reported. The heads were a skirt-type and extra-long size. The fractures occurred 8 months after the operation without any trauma. The cause of the fractures might be the impingement between the neck and the ceramic liner rim. At revision surgery, the fractured ceramic heads were replaced with sandwich-type ceramic liner and heads with ball type. After 3 years of revision surgery, ceramic head and ceramic liner in left total hip arthroplasty were fractured without any trauma. The ceramic head and liner were replaced with metal head and polyethylene liner at re-revisional operation.     

Mechanical failure in double cup arthroplasty of the hip

Summary Mechanical complications of double cup arthroplasty of the hip are common, particularly loosening of the components. This paper describes a series of 26 such operations with an average follow-up of 67 months. There was a failure rate or 53.8% and these hips had to be revised with another type of replacement. Our results are compared with other reported series.

---

Résumé Les complications mécaniques des arthroplasties de hanche par double cupule cimentée sont fréquentes et tout particulièrement leur descellement. Cet article analyse une série de 26 arthroplasties par cupules couplées scellées avec un recul moyen de 67 mois, comportant 53.8% d'échecs qui ont motivé la reprise par un autre type de prothèse. Ces résultats sont comparés à ceux des autres séries publiées d'arthroplasties par cupules couplées de la hanche.

     

Delayed fracture of a ceramic insert with modern ceramic total hip replacement

We report a case of ceramic liner fracture in a 34-year-old man that occurred 1 year 9 months after total hip arthroplasty with a BiCONTACT (Aesculap, Tuttlingen, Germany) ceramic-on-ceramic prosthesis. The ceramic liner was found within the metal shell in 4 large pieces and multiple small fragments in the peripheral portions. Its condition indicated that the possible mechanism of late ceramic liner chip fracture was repeated episodes of impingement between the prosthetic neck and the edge of the ceramic liner. Squatting, kneeling, and sitting cross-legged caused impingement. These positions are more common in Asian populations than in Western populations. After the joint was thoroughly irrigated, a new modular ceramic liner and a 28-mm ceramic head were implanted.     

Ceramic/ceramic total hip arthroplasty

Alumina-on-alumina total hip arthroplasty has been used for 30 years, mainly in Europe. The theoretical advantages of this combination are represented by its remarkable sliding characteristics, its very low wear debris generation, and its sufficient fracture toughness. These advantages are achieved if the material is properly controlled with high density, high purity, and small grains. The authors summarize the results obtained with ceramic/ceramic total hip arthroplasty. Information is provided about in vivo behavior regarding wear debris characterization and quantification, and histological tissue examinations for inflammatory reactions, which were not encountered except when alumina debris was mixed with metal or cement. Modification of socket fixation resulted in improved clinical outcomes. With a press-fit metal shell and an alumina liner utilized for 10 years, the results are excellent especially in a young and active population. Alumina-on-alumina seems at the moment to be one of the best choices when a total hip arthroplasty has to be performed in young and active patients. Received: March 22, 2000     

Computer-assisted cup positioning in total hip arthroplasty: usefulness, limits and future

The basic hypothesis for computer-assisted placement of the cup in total hip arthroplasty (THA) is that navigation will improve cup positioning around the targeted values previously defined in the literature as the gold standard for cup placement and reduce the number of outliers. Reducing the outliers will theoretically reduce the number of dislocation, improve range of motion and reduce wear. We will present the surgical technique, and the results of a prospective randomized study comparing computer-assisted cup positioning with free-hand placement. Furthermore we will outline some limitations of the navigation systems in hip surgery observed during our early experience through the results of complementary anatomical and clinical studies. Finally we will discuss the potential for future development of computer-assisted THA.     

Periprosthetic fracture between a constrained total knee arthroplasty and a long-stem total hip arthroplasty: treatment with a novel device

Supracondylar fracture of the femur occurred in a patient with a well-fixed constrained condylar total knee arthroplasty and an 8-in total hip femoral revision component. This unusual fracture was treated with a novel interpositional femoral intramedullary device that connected the total knee to total hip arthroplasty. The result was good at 5 years, with healed fracture and no loosening or osteolysis of either component.     

人工髋关节置换术后股骨假体周围骨折的治疗体会

目的总结人工髋关节置换术后股骨假体周围骨折治疗的经验和体会。方法 2002年1月至2008年1月治疗人工髋关节置换术后股骨假体周围骨折的患者21例,19例患者采用手术治疗,按照Vancouver分型标准进行分类,选择不同的手术方式进行治疗,包括：锁定加压接骨板固定,钢缆固定,同时结合异体骨板固定,关节翻修术等。结果术后随访2～6年,平均5年,所有患者骨折均获得骨性愈合,骨折平均愈合时间为6个月（4～9个月）,在最后随访时均有比较好的髋关节功能,Harris评分平均86分（78～92分）。结论按照股骨假体周围骨折的类型,选用合适的治疗方法,全面术前计划,可以取得比较满意的治疗效果。