组配式假体全髋关节置换术重建双下肢等长

目的探讨股骨颈组配式假体对全髋关节置换术后双下肢等长恢复的作用及临床结果。方法本回顾性研究纳入2009年6月至2011年11月使用Neck—modular髋关节假体进行全髋关节置换术的患者共37例,所有患者对侧髋关节均存在不同原因的解剖及异常,使用常规髋关节假体难以重建双下肢等长。根据对侧下肢长度术中调整颈长,重建下肢长度。术后测量患者双侧棘踝线,测量分析影像学上肢体长度恢复情况,评估患者主观感觉及术后Harris髋关节评分。结果所有37例患者术后双侧棘踝线测量及影像学上测量双侧下肢长度偏差均≤1cm,术后12周Harris评分平均84分（63—93）,所有患者髋关节均能获得良好的活动度,无一例出现股骨髋臼撞击症（FAI）和脱位。术后平均随访14．3个月（3—32个月）,Harris评分平均94分（76～98）。结论使用股骨颈组配式髋关节假体可恢复双下肢等长,并获得良好的关节活动度,减少并发症,临床结果满意。     

Trends in Total Hip Arthroplasty Implant Utilization in the United States

Total hip arthroplasty (THA) implant usage has evolved as experience has been gained with newer implant designs. The purpose of this study was to characterize trends in THA implant usage between 2001 and 2012. The Orthopedic Research Network, which includes 174 hospitals and ~ 105,000 THA, was used to evaluate trends in fixation, bearings, acetabular cup and liner, and femoral head usage. In 2012, 93% of THAs were cementless; 56% of THA bearings were metal-HXLPE; and 35% were ceramic-HXLPE. 99% of acetabular cups were modular. 61% of femoral heads were metal, 39% were ceramic, 51% were 36 mm, and 28% were 32 mm. THA implant usage trends favor cementless fixation, metal-on-polyethylene or ceramic-on-polyethylene bearings, modular acetabular cups, and large diameter femoral heads.     

Taper Corrosion in Modular Hip Prostheses : Analysis of Serum Metal Ions in 19 Patients

Recently, concerns have been raised about the use of metal-on-metal (MoM) implants. This has led to the recall of several resurfacing and large-diameter total hip arthroplasties (THA). Any MoM interface can be the cause of metal debris and adverse tissue reactions. We analyzed serum metal ions and HOOS scores in 19 of 306 patients treated with a THA with modular neck section. The only MoM interface in this particular implant is the taper between the neck and the stem. The articulating surface consists of a ceramic-on-polyethylene or ceramic-on-ceramic interface. As such, this study looks at the metal ion production from the modular neck section. One of 306 implants needed revision at 52-month follow-up because of an adverse reaction to metal debris (ARMD).     

Total Hip Arthroplasty in Patients With Postpolio Residual Paralysis: A Systematic Review

BackgroundPatients with postpolio residual paralysis can develop disabling hip arthritis in paralytic as well as a nonparalytic limb, warranting total hip arthroplasty (THA). Limited literature is available on the results of THA among these patients in the form of small series or case reports. We have undertaken a systematic review to evaluate the clinical outcome of THA in patients with poliomyelitis with hip pathologies.MethodsA systematic search of electronic databases of PubMed, Scopus, and Web of Science pertaining to English literature was undertaken from 1945 to August 2020 to assess the results of THA in patients with poliomyelitis. Information was gathered about demographics, indication, clinical course, complications, functional outcome, survival, and need for any revision surgery in these patients.ResultsThe literature search revealed 81 articles. Finally, after deduplication and manual selection, 16 relevant articles (128 hips) were included for evaluation. There is a paucity of literature evaluating THA in patients with poliomyelitis over the last 2 decades. The principal reason for arthroplasty was osteoarthritis of the hip in the ipsilateral (paralyzed) limb. A combination of cemented, uncemented, and hybrid implant fixation system was found to be used by surgeons. Addressing instability and perioperative management of limb length discrepancy were found to be challenging propositions.ConclusionTHA remains an effective intervention to relieve pain and improve quality of life in patients of poliomyelitis afflicted with either primary or secondary arthritis of the hip. The use of uncemented nonconstrained hip implant designs appears to demonstrate better results than constrained implants.     

High Failure at a Minimum 5-Year Follow-Up in Primary Total Hip Arthroplasty Using a Modular Femoral Trunnion

BackgroundModular femoral trunnions enable the surgeon to independently adjust offset, leg length, and anteversion in total hip arthroplasty (THA). However, modularity may result in an increased risk of fretting and corrosion along with a higher risk of implant dissociation or fracture. The purpose of this study is to evaluate mid-term survivorship of THAs using a cementless modular system.MethodsA consecutive series of 221 patients who underwent a primary THA using the ALFA II modular stem by a single surgeon between 2002 and 2004 were reviewed. Survivorship of the ALFA II modular hip system was evaluated at a minimum of 5 years postoperatively.ResultsOf the 221 patients, 28 (12.7%) died from causes unrelated to the surgery before adequate follow-up, and 64 (29.0%) patients were lost to follow-up. The remaining 129 patients had a mean 6.5-year (range: 5-8 years) follow-up. All-cause survivorship of the modular stem system was 81% (95% confidence interval = 69-90) at a mean 6.5-year follow-up. Of the 25 (19.4%) cases requiring revision surgery, 52.0% was for dissociation of the modular components, 32.0% was for fracture of the prosthesis, 12.0% was for instability/multiple dislocations, and 4.0% was for chronic septic THA. Body mass index (odds ratio = 1.080) and offset (odds ratio = 1.254) were independent risk factors for mechanical failures of the modular stem system.ConclusionThe modular stem hip system of interest in this study demonstrates a high failure rate at mid-term follow-up, and we caution against the use of similar designs in primary THAs.     

Failure mechanism of a constrained liner: a case report

Instability after primary and revision total hip arthroplasty continues to be a problem. The use of a constrained system helps manage this problem. A new constrained total hip arthroplasty, Trilogy constrained liner (Zimmer, Warsaw, IN), is currently in use. We report a case showing dislocation following a Trilogy constrained total hip arthroplasty. In this case, when an impingement between the femoral neck and the anterior part of the polyethylene liner occurred, the hip dislocated easily although both polyethylene and reinforcing ring were properly positioned. The lever-out test showed that the Trilogy constrained liner is safe and compares favourably with other implants. Surgeons should be aware that constrained acetabular systems are not infallible and they should pay attention to place implants in good position even when constrained THA is performed.     

Femoral implant neck fracture following total hip arthroplasty. A report of three cases

Femoral neck fracture following total hip arthroplasty (THA) is an infrequent complication. Of 1808 T-28 and TR-28 THA performed at our clinic, 32 fractures of the femoral stem occurred, but none through the femoral neck. Two femoral neck fractures ten years following Trapezoidal-28 THA have recently been referred to our clinic. A separation of the head and neck of a Dual Lock prosthesis at two years was also referred. Failure of these implants suggests that significant forces are encountered in this region of a femoral component. Newer modular implant designs must consider these loads.     

立体影像学分析对组配式全髋关节置换术后股骨假体迁移的早期评估

目的 探讨立体影像学分析(roentgen stereophotogrammetric analysis,RSA)对全髋关节置换术后股骨假体迁移的评估价值.方法 2009年5月至2010年4月,行组配式全髋关节置换37例,男25例,女12例;年龄58～72岁,平均(60.23±5.64)岁.退行性骨关节炎32例,股骨颈骨折3例,髋关节发育不良2例.术后3、6、12、24个月采用Harris髋关节评分评估髋关节功能及RSA评估股骨假体的早期迁移度.结果 Harris髋关节评分从术前(26.36±10.56)分提高至术后不同随访时间点的(78.24±12.72)分、(84.51±16.05)分、(86.72±9.34)分及(87.55±8.97)分,与术前比较差异均有统计学意义.无假体翻修病例,3例有轻微的大腿痛.RSA评估发现早期迁移幅度个体差异较大,术后3～6个月存在较高的初始迁移.36例于术后24个月达到临床和生物学稳定,1例表现为假体进行性迁移.股骨假体向远端迁移(1.37±0.59) mm、向后迁移(1.37±0.54) mm,与术前差异有统计学意义.术后24个月内股骨假体向远端迁移与向后迁移呈正相关(r=0.3,P=O.O1),假体在横断面和矢状面上呈现出相对宿主骨界面稳定固定的趋势,股骨假体向远端及向后的倾斜或旋转移位主要发生在术后3个月内.不同尺寸的股骨头假体和不同偏心距的组配式股骨颈假体与发生在各个方向的迁移度无相关性.结论 RSA为组配式全髋关节置换术后股骨假体迁移度的早期评估提供了客观依据,可用于评估人工关节假体的早期稳定性.     

The squeaking hip: a cause for concern-disagrees

Total hip arthroplasty with ceramic-on-ceramic bearing surfaces has demonstrated low wear with excellent clinical outcomes. More recently, concerns have surfaced because of the presence of audible squeaking in some ceramic-on-ceramic THA patients. The incidence of this phenomenon has been low and has infrequently required reoperation. The exact etiology of squeaking remains unclear but is likely related to variations in surgical technique, patient selection, and implant design, particularly those designs that result in premature femoral neck-acetabular component rim impingement such as the presence of modular ceramic liner designs that are placed within a titanium encasement which has an extended rim. Hopefully, with continued improvements in design, materials, and component positioning, squeaking following ceramic-on-ceramic THA can be minimized.     

Metal-on-metal surface replacement: a triumph of hope over reason: affirms

Metal-on-metal hip resurfacing offers some potential for total hip arthroplasty (THA) in the young patient. However, short- and intermediate-term results of the currently available implants have failed to demonstrate advantage over conventional THA. The risks of femoral neck fracture or avascular necrosis have been disappointing early limitations of the procedure. The Australian Joint Registry reports a 5-year revision rate of all hip resurfacings of 3.8%, compared with conventional THAs at 2.8%, and a 9-year cumulative revision rate of 7.2% for hip resurfacings. Recent reports of femoral neck erosion and pseudotumors associated with resurfacing have raised concern about the survivorship of the procedure in some patients. Recently, the British Medicines and Healthcare Product Regulatory Agency issued an alert over adverse reactions associated with metal-on-metal THAs, with particular concern expressed about hip resurfacings. Acetabular bone stock may not be conserved when large-diameter femoral head components are used, depending on the surgical technique and implant design. In hip resurfacing, the minimum diameter femoral component avoids notching of the femoral neck; thus, larger diameter acetabular components may be necessary to accommodate the femoral component. Hip resurfacing is contraindicated in cases of avascular necrosis of the femoral head, especially with cysts >1 cm in diameter, with severe slipped capital femoral epiphysis, and in some posttraumatic arthroses; furthermore, the biomechanics of the resurfaced hip appear to be less reliably restored than with conventional THA. The hypothesis that resurfacing is a more conservative procedure than conventional THA remains unproven at this time. Given the documented intermediate failure rates of resurfacing, metal-on-polyethylene is the more successful implant choice.     

Long-Term Clinical and Radiological Outcomes of Primary Total Hip Arthroplasty with Modular Femoral Stem in Middle-Aged Asian Patients

BackgroundThere is insufficient information regarding the outcome of primary total hip arthroplasty (THA) with the modular femoral stem in middle-aged patients. This study aimed to assess long-term clinical and radiological outcomes of primary THA using the original or modified modular hip system (S-ROM) in middle-aged Asian patients.MethodsA retrospective review identified 98 primary THAs that used a modular stem and were undertaken between 1997 and 2009 in patients younger than 58 years, for whom at least 5 years of follow-up data were available. Clinical data and radiograph assessments were reviewed to analyze differences between the original and modified modular stem groups.ResultsThe mean patient follow-up duration was 148.3 months, and the follow-up ratio was 89.1%. The Kaplan–Meier analysis revealed that the survival rate of both stems was 98.9% at 10 years and 89.8% at 15 years. Although no statistically significant differences in the survival rate were observed between the stem designs, the original stem group had increased incidence of thigh pain compared with the modified stem group. In total, 12 and 54 hips showed change in stem alignment and osteolysis, respectively.ConclusionThe findings of this study show that the modular stems have a high survival rate, and results suggest positive outcomes among the Asian population over the long term. Although there were very few differences between the stem designs, the results suggest that the modified modular stem could prevent thigh pain and that selection of the implant based on the bone shape is important for THA.     

A Comparison of Two Implant Systems in Restoration of Hip Geometry in Arthroplasty

Background  

Restoration of hip offset and leg length during THA is often limited by available implant geometries. The recent introduction of femoral components with a modular junction at the base of the neck (two modular junction components) has expanded the options to restore femoral offset and leg length.     

How Have Alternative Bearings and Modularity Affected Revision Rates in Total Hip Arthroplasty?

Background

Total hip arthroplasty (THA) continues to be one of the most successful surgical procedures in the medical field. However, over the last two decades, the use of modularity and alternative bearings in THA has become routine. Given the known problems associated with hard-on-hard bearing couples, including taper failures with more modular stem designs, local and systemic effects from metal-on-metal bearings, and fractures with ceramic-on-ceramic bearings, it is not known whether in aggregate the survivorship of these implants is better or worse than the metal-on-polyethylene bearings that they sought to replace.

Questions/purposes

Have alternative bearings (metal-on-metal and ceramic-on-ceramic) and implant modularity decreased revision rates of primary THAs?

Methods

In this systematic review of MEDLINE and EMBASE, we used several Boolean search strings for each topic and surveyed national registry data from English-speaking countries. Clinical research (Level IV or higher) with ≥ 5 years of followup was included; retrieval studies and case reports were excluded. We included registry data at ≥ 7 years followup. A total of 32 studies (and five registry reports) on metal-on-metal, 19 studies (and five registry reports) on ceramic-on-ceramic, and 20 studies (and one registry report) on modular stem designs met inclusion criteria and were evaluated in detail. Insufficient data were available on metal-on-ceramic and ceramic-on-metal implants, and monoblock acetabular designs were evaluated in another recent systematic review so these were not evaluated here.

Results

There was no evidence in the literature that alternative bearings (either metal-on-metal or ceramic-on-ceramic) in THA have decreased revision rates. Registry data, however, showed that large head metal-on-metal implants have lower 7- to 10-year survivorship than do standard bearings. In THA, modular exchangeable femoral neck implants had a lower 10-year survival rate in both literature reviews and in registry data compared with combined registry primary THA implant survivorship.

Conclusions

Despite improvements in implant technology, there is no evidence that alternative bearings or modularity have resulted in decreased THA revision rates after 5 years. In fact, both large head metal-on-metal THA and added modularity may well lower survivorship and should only be used in select cases in which the mission cannot be achieved without it. Based on this experience, followup and/or postmarket surveillance studies should have a duration of at least 5 years before introducing new alternative bearings or modularity on a widespread scale.     

Dissociation of modular total hip arthroplasty at the femoral head-neck interface after loosening of the acetabular shell following hip dislocation

Modular component dissociation is a potential problem of current modular total hip arthroplasty (THA) systems. We describe a case of dissociation of the modular THA at the femoral head-neck interface after loosening of the acetabular shell during closed reduction for posterior dislocation of THA. The causes of this dissociation and acetabular shell loosening are discussed. Successful treatment was provided with surgical revision of the acetabular and the femoral head components. The present case serves as a graphic reminder that the acetabular shell overhanging the acetabular bone must be avoided when implanting modular THA components.     

Metal Articulations as a Source of Total Hip Arthroplasty Pain

The consensus systematic risk stratification algorithm from the American Association of Hip and Knee Surgeons, the American Academy of Orthopaedic Surgeons, and The Hip Society summarizes clinical challenges in evaluation and treatment of metal-on-polyethylene total hip arthroplasty (THA) patients with adverse local tissue reaction (ALTR) due to mechanically assisted crevice corrosion (MACC), reviews up-to-date evidence, and identifies the areas for future research in order to provide a useful resource for orthopedic surgeons providing care to these patients. A painful THA has various intrinsic and extrinsic causes. ALTR is one of the intrinsic causes in patients with painful THA. The occurrence of ALTR due to MACC at modular junctions is likely to be multifactorial, including implant, surgical, and patient factors. Therefore, a systematic evaluation needs to involve a focused clinical history, detailed physical examination, laboratory tests, and imaging in order to identify potential differential diagnoses. There should be a low threshold to perform a systematic evaluation of patients with painful non–metal-on-metal THA, including patients with metal-on-polyethylene THA, and modular dual-mobility THA with the CoCr metal acetabular insert, as early recognition and diagnosis of ALTR due to MACC will facilitate initiation of appropriate treatment prior to significant adverse biological reactions. Specialized tests such as blood metal analysis and metal artifact reduction sequence magnetic resonance imaging are important modalities in evaluation and management of ALTR in patients with painful THA.     

Dual Mobility Total Hip Arthroplasty Is Not Associated with a Greater Incidence of Groin Pain in Comparison with Conventional Total Hip Arthroplasty and Hip Resurfacing:A Retrospective Comparative Study

Background

Groin pain is a common long-term complication of total hip arthroplasty (THA). Femoral head size has been proposed as one of the primary causes. The implants used in dual mobility (DM) THA have large outer-bearing articulations, which could increase the risk of post-operative groin pain. Hip resurfacing (HR), too, has been shown to be associated with a risk of groin pain.

Questions/Purposes

The goals of this study were to compare the incidence of groin pain at 1 year after hip arthroplasty in patients with different femoral head diameters and in patients undergoing conventional THA, DM THA, and HR.

Methods

After combing an institutional registry for all patients who had undergone THA or HR for primary hip osteoarthritis, we included 3193 patients in the analysis; 2008 underwent conventional THA, 416 underwent DM THA, and 769 underwent HR. We used logistic regression modeling to analyze the relation of groin pain at 1 year after surgery to patient demographics and clinical characteristics, including age, sex, body mass index (BMI), University of California at Los Angeles activity score at 1 year after surgery, bearing couple, and the ratio of acetabular diameter to femoral head diameter. We also measured cup inclination and anteversion in a subset of patients with and without groin pain at 1 year to assess whether pain could be related to implant position.

Results

Overall, 8.7% of patients reported groin pain at 1 year. Patients with groin pain were younger and had lower BMIs. There were increased odds of groin pain with a greater cup-to-head ratio, although DM implants, interestingly, were not significantly associated with groin pain; this may be attributable to so much of their movement taking place inside the implant. Subgroup analysis measuring cup inclination and anteversion showed no difference in cup position between patients with and without pain.

Conclusion

In this population of hip arthroplasty patients, the incidence of groin pain 1 year after surgery did not differ among patients undergoing DM and conventional THA; DM THA in particular was not associated with a higher risk of groin pain, despite its comparatively larger femoral head sizes. HR, on the other hand, was associated with a higher risk of pain. Appropriate implant sizing and bearing couple choice may optimize the functional benefit of THA.

     

Poor Short Term Outcome with a Metal-On-Metal Total Hip Arthroplasty

Metal-on-metal (MoM) bearings for total hip arthroplasty (THA) have come under scrutiny with reports of high failure rates. Clinical outcome studies with several commercially available MoM THA bearings remain unreported. We evaluated 78 consecutive MoM THAs from a single manufacturer in 68 patients. Sixty-six received cobalt–chrome (CoCr) monoblock and 12 received modular titanium acetabular cups with internal CoCr liners. Femoral components were titanium with modular necks. At average 2.1 years postoperatively, 12 THAs (15.4%) demonstrated aseptic failure (10 revisions, 2 revision recommended). All revised hips demonstrated capsular necrosis with positive histology reaction for aseptic lymphocytic vasculitis-associated lesions/adverse local tissue reactions. Prosthetic instability following revision surgery was relatively common. Female gender was a strong risk factor for failure, though smaller cups were not. Both monoblock and modular components fared poorly. Corrosion was frequently observed around the proximal and distal end of the modular femoral necks.     

Surgical challenges in complex primary total hip arthroplasty.

Complex primary total hip arthroplasty (THA) is defined as primary THA in patients with compromised bony or soft-tissue states, including but not limited to dysplastic hip, ankylosed hip, prior hip fracture, protrusio acetabuli, certain neuromuscular conditions, skeletal dysplasia, and previous bony procedures about the hip. Intraoperatively, provisions must be made for the possible use of modular implants and/or bone grafts. In this article, we review the principles of preoperative, intraoperative, and postoperative management of patients requiring a complex primary THA.     

Dissociation of modular total hip arthroplasty at the neck–stem interface without dislocation

Modular femoral and acetabular components are now widely used, but only a few complications related to the modularity itself have been reported. We describe a case of dissociation of the modular total hip arthroplasty (THA) at the femoral neck–stem interface during walking. The possible causes of this dissociation are discussed. Successful treatment was provided with surgical revision and replacement of the modular neck components. Surgeons who use modular components in hip arthroplasties should be aware of possible early complications in which the modularity of the prostheses is the major factor of failure.     

Surgical challenges in complex primary total hip arthroplasty

Complex primary total hip arthroplasty (THA) is defined as primary THA in patients with compromised bony or soft-tissue states, including but not limited to dysplastic hip, ankylosed hip, prior hip fracture, protrusio acetabuli, certain neuromuscular conditions, skeletal dysplasia, and previous bony procedures about the hip. Intraoperatively, provisions must be made for the possible use of modular implants and/or bone grafts. In this article, we review the principles of preoperative, intraoperative, and postoperative management of patients requiring a complex primary THA.