National trends and in hospital outcomes for total hip arthroplasty in avascular necrosis in the United States

Purpose

While a majority of total hip arthroplasty (THA) is performed for osteoarthritis (OA), a significant portion is performed in the setting of avascular necrosis (AVN). The purpose of this study is to evaluate recent trends, patient demographics, and in hospital outcomes for primary THA in the setting of AVN in the United States.

Methods

The National Hospital Discharge Survey database was searched for patients admitted to US hospitals after a primary THA for the years 2001-2010. Patients were then separated into two groups by ICD-9 diagnosis codes for OA and AVN.

Results

The rates of THA for AVN (r?=?0.65) and THA for OA (r?=?0.82) both demonstrated a positive correlation with time. The mean patient age of the AVN group was significantly lower (56.9 vs 65.9 years, p?<?0.01). Men accounted for 51.9 % of the AVN group and 43.0 % of the OA group (p?<?0.01). The AVN group had a significantly higher percentage of African Americans (11.2 % vs 5.4 %, p?<?0.01) when compared to the OA group. The AVN group had a higher rate of myocardial infarction (0.3 % vs 0.07 %, p?=?0.0163) and a higher average number of medical co-morbidities (5.16 vs 4.77, p?<?0.01).

Conclusions

Patients undergoing THA for AVN were more likely to be younger, male, African American, have more medical co-morbidities, and more likely to have a myocardial infarction than those with OA. While the number of primary THAs performed for AVN in the United States has increased over the past ten years, the rate of primary THA for OA increased at a much more rapid rate.

     

Revision total hip arthroplasty

Two hundred and ten hips in 206 patients who had an initial total hip arthroplasty performed at the Mayo Clinic between 1969 and 1978 required revision of the arthroplasty at the Mayo Clinic for reasons other than infection. One hundred and sixty-two of the patients (166 hips) were followed both clinically and roentgenographically for two years or more. One hundred and forty-five (90 per cent) reported that they had improvement after the surgical revision. Complications that occurred with revision included deep sepsis, superficial would infection, dislocation, intraoperative femoral fracture, and postoperative femoral fracture. Roentgenographic analysis showed probable loosening in thirty-three acetabular components (20.1 per cent) and seventy-two femoral components (44 per cent). Symptomatic loosening (moderate to severe pain and probable roentgenographic loosening) was seen in thirty-five patients. Eight patients required a second revision for this reason, and seven others required a second revision for other reasons. Modified Harris hip scores, calculated for 108 hips, showed a good or excellent result in sixty-seven hips (62 per cent), a fair result in twelve (11 per cent), and a poor result in twenty-nine (27 per cent). Using a new Mayo Clinic hip score that incorporates roentgenographic data (which will be described) in the evaluation of 165 revised hips, there was a good or excellent result in eighty-five (52 per cent), a fair result in thirty-two (19 per cent), and a poor result in forty-eight hips (29 per cent). Although 90 per cent of the patients thought that their condition had improved, the high incidence of roentgenographic signs of probable loosening of a component is of serious concern.     

全髋关节置换翻修术

全髋关节翻修术目前已成为临床髋关节外科领域中最重要研究课题之一,不仅仅因为需要施行关节翻修的患者数量逐年增加,而且更重要的髋关节翻修手术的基础理论研究和临床实践都面临巨大挑战.     

In-hospital cost of total hip arthroplasty in Canada and the United States

BACKGROUND: There is little information comparing the costs of specific surgical procedures performed in Canada and those done in the United States. The objective of this study was to compare the in-hospital costs associated with primary total hip arthroplasty performed in the two countries. METHODS: In-hospital costs of 1679 consecutive patients (940 Canadian and 739 American patients) who underwent total hip arthroplasty were extracted from three Canadian and three United States teaching hospitals between 1997 and 2001. Participating hospitals used the same cost accounting system to provide per-patient demographic, clinical, and cost data. Canadian dollar costs were converted to United States dollar costs with use of purchasing power parities. RESULTS: The baseline clinical characteristics of patients undergoing total hip arthroplasty in Canada and the United States were similar. The American patients were a mean of 4.6 years older than the Canadian patients (mean [and standard deviation], 67.8 +/- 12.4 years compared with 63.2 +/- 14.9 years). The median cost for the primary arthroplasty was $6080 (mean [and standard error of the mean], $6766 +/-$119) at the three Canadian hospitals and $12,846 (mean, $13,339 +/-$131) at the United States hospitals (p < 0.0001). The mean length of stay (and standard deviation) was 7.2 +/- 4.7 days for the Canadian patients and 4.2 +/- 2.0 days for the American patients. Implants at one hospital in the United States were found to be four times more costly than those in a Canadian hospital. CONCLUSIONS: Higher in-hospital costs were found for the American hospitals despite the fact that they had a significantly shorter patient length of stay compared with Canadian centers (p < 0.0001). Canadian hospitals should follow the lead of their counterparts in the United States and implement strategies to decrease the length of stay in the hospital, while institutions in the United States should revisit their ability to better manage the costs related to a primary total hip arthroplasty, particularly by controlling unit costs.     

Ceramic total hip arthroplasty in the United States: safety and risk issues revisited

The advantages of all-alumina bearings are superb wear resistance, stability, and inertness demonstrated over 3 decades. The disadvantage is a small risk for brittle fracture, as described in this paper. Surveying the latest ceramic hip series reported in recent journal articles or presented at the 6th World Biomaterials Congress, we found 11 studies representing more than 35,000 cases followed for 3 to 25 years. There were 24 reported fractures. A unique survey of hip complications in the 1990s found a fracture risk of approximately 1.4 per 1000 ceramic balls used in the United States. A company database holding more than 2.5 million records described the overall fracture risk as 1 per 10,000 cases. Initial use of ceramic cup inserts indicated a 2% to 3% incidence of chipping during surgery. Beginning in 1997, the number of ceramic-metal cup-locking cases entered into a US Food and Drug Administration ceramics database was more than 2400, with no fractures reported by the FDA in July 2003.     

Revision of infected total hip arthroplasty

Extension of infection down the medulla of the femur to the supracondylar region may occur in cases of chronic infected total hip arthroplasty. Because this cannot always be identified before operation, the femur should be reamed and flushed proximally from the lateral condyle in all cases where there is suspicion of infection around the femoral component. Where infection is unequivocal and extensive, a period of irrigation and suction drainage is advisable before final total hip arthroplasty. After the prosthesis has been inserted in either one or two stages, it is wise not to rely on antibiotic cement mixtures alone but to monitor the bacterial flora and prescribe local antibiotic therapy accordingly.     

Revision of failed total hip arthroplasty

Ninety-seven revisions of total hip replacements are reviewed with a median time of observation of 47 months. Satisfactory pain relief was obtained in 86%. There were six complete failures which were reduced to three by further surgery. One hip became infected and was excised. In 12 cases the revisions were complicated by peroperative fractures and in five by dislocations. Radiographic analysis disclosed a high percentage of periarticular ossification and 25 cases of radiographic loosening of the femoral implant.     

髋关节置换术后感染的手术治疗

目的探讨髋关节置换术后感染手术治疗的临床疗效。方法共11例髋关节置换术后感染患者,男6例,女5例,平均63岁(54～71岁)。术前Harris评分25～40分,平均33分。术前血沉均有升高,平均61mm/h(34～80mm/h)。所有患者术前、术中均进行细菌培养和药敏试验。11例中一期翻修6例,二期翻修5例,术后均置引流管引流并根据药敏试验应用抗生素。11例患者早期感染2例,晚期感染9例。术前穿刺及窦道脓液培养阳性8例,其中5例为表皮葡萄球菌,2例为大肠埃希氏菌,1例为金黄色葡萄球菌。结果术后11例患者随访12～31个月,平均17个月,感染均未复发,血沉、血常规检查正常,术后Harris评分为79～92分,平均84.2分,较术前平均提高51.2分(P<0.05)。结论髋关节置换术后感染,只要诊断明确,合理使用抗生素和抗生素骨水泥,一期翻修同样可以取得满意的临床疗效。     

人工股骨头置换术后全髋关节翻修术的临床研究

目的探讨人工股骨头置换术后全髋关节翻修术的手术指征和技巧。方法回顾性分析1997年6月至2000年6月行人工股骨头置换术后全髋关节翻修术的56例患者的临床资料。其中男性31例,女性25例;年龄64—75岁,平均68岁。翻修原因中,人工股骨头置换术后髋臼磨损29例（51．8％）,髋臼磨损及股骨头中心性脱位14例（25．0％）,股骨柄松动12例（21．4％）,股骨柄断裂1例（1．8％）。Harris评分术前平均37分（28～40分）。所有病例均一期翻修,有骨质缺损者同时植骨。结果49例患者术后获得平均7年（5—8年）随访,7例失访。末次随访Harris评分平均88分（84～90分）。全部病例术后无伤口感染和神经血管损伤。5例患者出现并发症,其中扩髓时骨皮质不全骨折1例,术后下肢深静脉血栓3例,髋关节脱位1例。随访患者中无髋臼及股骨柄假体需要再度翻修。X线片显示人工关节假体位置正常,无松动感染征象。结论髋臼磨损及股骨头中心性脱位是人工股骨头置换术后全髋关节翻修的主要原因。中期临床随访结果显示,若手术指征正确,手术技巧娴熟,该翻修手术可以获得良好的临床效果。     

Revision total hip arthroplasty for metal-on-metal failure

Metal-on-metal (MoM) arthroplasty systems became popular in the early-2000s due to presumed advantages of improved wear characteristics and superior stability. However, subsequent reports of abnormal soft-tissue reactions to MoM implants and national registry data reporting high failure rates raised concerns. Early outcomes of revision total hip arthroplasty (THA) for adverse reaction to metal debris (ARMD) were poor, leading to development of surveillance programs and a trend towards early revision surgery. Patients with MoM arthroplasties require surveillance, comprehensive history and physical examination, imaging with ultrasound or magnetic resonance imaging (MRI), and laboratory evaluation including metal ion levels. Operative strategies for revision THA vary from exchange of modular components to extensive debridement and reconstruction with revision components. Surgeons should be aware of the increased risks of dislocation and infection following revision THA for ARMD. However, there is growing evidence that early revision surgery prior to extensive soft tissue destruction results in improved outcomes and decreased re-operation rates. It is estimated that >1 million MoM articulations have been implanted, with a large proportion still in situ. It is imperative to understand the aetiology, presentation, and management strategies for these patients to optimise their clinical outcomes.     

Revision total hip arthroplasty due to pain from hypersensitivity to cobalt-chromium in total hip arthroplasty

We report a case with hypersensitivity to CoCr in total hip arthroplasty coupled with conventional polyethylene and CoCr femoral head. The patient complained of left hip pain and systemic fever, and computed tomography imaging revealed a periprosthetic cystic lesion, so we performed revision total hip arthroplasty using a titanium stem and ceramic head and highly crosslinked polyethylene. Hip pain and cystic lesion disappeared 3 years after revision surgery.     

Revision total hip arthroplasty: hospital cost and reimbursement analysis

Revision total hip arthroplasty is a complex surgical procedure that frequently requires high levels of hospital resources. The purpose of the current study was to report the actual costs and reimbursement to the hospital for a stratified group of patients having revision total hip arthroplasty based on a severity index. The clinical and financial records of 49 patients (51 hips) stratified by complexity of revision were reviewed. Clinical variable included age, length of stay, operating time, estimated blood loss, number of transfusions, implant type, metallic augmentation, use of bone graft, and time spent in the postanesthesia care unit. Financial review included the actual fixed and variable costs associated with each procedure. Hospital costs associated with revision total hip arthroplasty were significantly greater in the most complex revisions and in older patients. The use of bone grafting techniques on the femur resulted in significantly greater costs. The average loss to the hospital was $5402 US dollars per procedure with a range of $5657 (US dollars) profit to $28,780 (US dollars) loss. Procedures in patients younger than 65 years has an average loss of $1133 US dollars. All procedures in patients who were 65 years or older resulted in a loss to the hospital, with the average loss being $8617 US dollars. Despite improvements in length of stay, use of clinical pathways, and negotiated discounts on implants, the hospital loss on each hip revision procedure averaged $5402 US dollars.     

Revision total hip arthroplasty performed through the Hueter interval

Revision total hip arthroplasty through the direct anterior approach is technically challenging but offers some advantages in exposure of the acetabulum. This study presents a retrospectively reviewed consecutive series of fifty-one patients who underwent revision total hip arthroplasty through the anterior approach utilizing various extensions of this technique. The anatomic approach is discussed as well as problems as encountered in our series.     

Revision total hip arthroplasty: the limits of fully coated stems

Femoral revision with a 7-inch or 8-inch fully porous-coated stem may not provide reliable long-term results in patients with moderate bone loss. The purpose of this study was to evaluate the limits of fully porous-coated stems and to create a treatment algorithm for femoral deficiencies. Fifty-one patients with either a 10-inch or 9-inch calcar fully porous-coated stem, 10 patients with impaction bone grafting, and 10 patients with a modular tapered stem were evaluated at an average 4.2 years postoperatively. The mechanical failure rate among the 9-inch and 10-inch fully porous-coated stems was 0% in Type III B defects with femoral canals less than 19 mm (15 patients), 18% in Type IIIB defects with femoral canals greater than 19 mm (2 of 11 patients) and 37.5% in Type IV defects (three of eight patients). There were no mechanical failures observed among the bone packing or modular tapered stems. Patients with Type IIIB defects and a femoral canal less than 19 mm can be treated successfully with either a 10-inch or 9-inch calcar fully porous-coated stem. However, patients with Type IIIB defect and an endosteal canal greater than 19 mm or a Type IV defect require alternative methods of reconstruction such as a modular tapered stem or a bone packing procedure.