Concerns with alumina bipolar hemiarthroplasties compared to metal bipolar hemiarthroplasties when performed for nontraumatic osteonecrosis of the femoral head.

PURPOSE: A nationwide multicenter follow-up cohort study of hip replacement arthroplasties performed for nontraumatic osteonecrosis of the femoral head (ONFH) aimed to answer the following questions: What factors were associated with need for reoperation? Although many modifications were made in bipolar hemiarthroplasties (BPs) to improve their durability, could we find any evidence of their efficacy? METHODS: Excluding 58 infected hips and 43 ABS THAs with very poor survivorship, we analyzed 7393 arthroplasties; 6284 total hip arthroplasties (THAs), 886 BPs, 188 total resurfacing arthroplasties, and 35 hemi-resurfacing arthroplasties (hRSs). In the 886 BPs, 440 hips had a smooth small-diameter prosthetic neck (nBPs), 667 hips had a smooth neck (sBPs), 116 hips had highly cross-linked polyethylene in the outer head (hBPs), and 238 hips had an outer head whose outer surface was alumina ceramic (aBPs) (648 hips had an outer head whose outer surface was metal [mBPs]). Multivariate analyses using a Cox proportional-hazard model analyzed risk factors. RESULTS: Follow-up ranged from 0.1 to 27 (average, 6.9) years, during which 265 hips (3.6%) needed reoperation. Combined systemic steroid use and excessive alcohol consumption and lateral approach were associated with higher risks, aBPs were less durable than THAs or mBPs, and hRSs were inferior to the others. Regarding BPs, the following divisions did not influence their survivorship; nBP or not, sBP or not, and hBP or not. CONCLUSIONS: Factors associated with reoperation risk were identified as described above. The modifications made in BPs did not improve their durability, but aBPs made it worse. LEVEL OF CLINICAL EVIDENCE: Level III, therapeutic cohort study.

Nationwide multicenter follow-up cohort study of hip arthroplasties performed for osteonecrosis of the femoral head.

PURPOSE: To identify modifiable factors related to post-operative dislocation and reoperation in patients with osteonecrosis of the femoral head (ONFH) in a large cohort. METHODS: We studied 4995 hip arthroplasties: total hip arthroplasty (THA) was performed in 79% of patients; bipolar hemiarthroplasty (BP), 17%; total resurfacing arthroplasty (tRS), 3%; and hemi-resurfacing arthroplasty (hRS), 1%. A new type of BP (accounting for 49% of BPs) comprised a femoral component with a polished or smooth, small-diameter (approximately 10 mm) neck with a round or oval axial cut surface and no sharp corners. RESULTS: The infection rate was relatively low (0.56%) even though 58% of cases of ONFH were associated with systemic steroid use, a known risk factor for infection. Post-operative dislocation occurred in 4.3% of cases, with re-operation needed in 3.9%. The dislocation rate was related to surgery type: 5.2% in THA, 0.9% in BP, and 0% in tRS and hRS. Among total arthroplasties with six month or longer follow-up (3670 THAs and 159 tRSs), the risk factors for post-operative dislocation were younger (≤ 40 years) or older (≥ 62 years) age, higher body weight, posterolateral approach, and smaller prosthetic head diameter. Regarding the need for re-operation, higher body weight and surgery type were identified as risk factors. CONCLUSIONS: The relatively high dislocation rate of 5.2% in THA is a cause for concern. The identified risk factors for dislocation should be considered when selecting THA for treatment. Prosthesis survivorship in hRSs was inferior to that in BPs or THAs. Body weight also affected the survivorship of hip arthroplasties.

Time elapsed from definitive diagnosis to surgery for osteonecrosis of the femoral head: a nationwide observational study in Japan.

OBJECTIVES: This study documents the time elapsed from the diagnosis of osteonecrosis of the femoral head (ONFH) to surgery, exploring the factors that influence ONFH severity. DESIGN: Retrospective observational study of a nationwide database. SETTING: The Kaplan-Meier method with log-rank tests was applied to examine the period from definitive diagnosis of ONFH to surgery using any surgery as the end point. For bilateral cases, the date of the first surgery was the endpoint. PARTICIPANTS: This study included 2074 ONFH cases registered in 34 university hospitals and highly specialised hospitals of the multicentre sentinel monitoring system of the Japanese Investigation Committee between 1997 and 2018. MAIN OUTCOME MEASURE: The primary outcome was the time from diagnosis to surgery. The secondary outcome was the proportion of subjects remaining without surgery at 3, 6 and 9 months, and at 1, 2 and 5 years after diagnosis. RESULTS: The median time to surgery was 9 months (IQR 4-22 months) after diagnosis of ONFH. The time to surgery was significantly shorter in the alcohol alone group and the combined corticosteroid and alcohol group than in the corticosteroid alone group (p=0.018 and p<0.001, respectively), in early stage ONFH with no or mild joint destruction (stages II and III, p<0.001), and with joint preserving surgery (p<0.001). The proportion without surgery was 75.8% at 3 months, 59.6% at 6 months, 48.2% at 9 months, 40.5% at 1 year, 22.2% at 2 years and 8.3% at 5 years. CONCLUSION: ONFH has been considered to be an intractable disease that often requires surgical treatment, but the fact that surgery was performed in more than half of the patients within 9 months from diagnosis suggests severe disease with a significant clinical impact. TRIAL REGISTRATION NUMBER: Chiba University ID1049.

Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ): a patient-based evaluation tool for hip-joint disease. The Subcommittee on Hip Disease Evaluation of the Clinical Outcome Committee of the Japanese Orthopaedic Association.

BACKGROUND: The Japanese Orthopaedic Association Hip Score is widely used in Japan, but this tool is designed to reflect the viewpoint of health-care providers rather than that of patients. In gauging the effect of medical therapies in addition to clinical results, it is necessary to assess quality of life (QOL) from the viewpoint of patients. However, there is no tool evaluating QOL for Japanese patients with hip-joint disease. METHODS: With the aim of more accurately classifying QOL for Japanese patients with hip-joint disease, we prepared a questionnaire with 58 items for the survey derived from 464 opinions obtained from approximately 100 Japanese patients with hip-joint disease and previously devised evaluation criteria. In the survey, we collected information on 501 cases, and 402 were subjected to factor analysis. From this, we formulated three categories-movement, mental, and pain-each comprising 7 items, for a total of 21 items to be used as evaluation criteria for hip-joint function. RESULTS: The Cronbach's α coefficients for the three categories were 0.93, 0.93, and 0.95, respectively, indicating the high reliability of the evaluation criteria. The 21 items included some related to the Asian lifestyle, such as use of a Japanese-style toilet and rising from the floor, which are not included in other evaluation tools. CONCLUSIONS: This self-administered questionnaire may become a useful tool in the evaluation of not only Japanese patients, but also of members of other ethnic groups who engage in deep flexion of the hip joint during daily activities.

[Whether bone quality matters or not in durability of total hip arthroplasty? Bone quality matters in durability of total hip arthroplasty].

Evolution in surgical techniques and prosthetic designs and materials has improved durability of total hip arthroplasty (THA) . As a result, bone quality of the hip joint has become an important risk factor limiting the durability of THA. In preparation of the acetabular bony bed, the subchondral bone or eburnated bone of good bone quality should be preserved. Sockets fixed in joints with atrophic osteoarthrosis were at a higher risk for loosening than those in joints with normotrophic or hypertrophic osteoarthrosis. Femoral components set in the proximal femurs with a stovepipe canal were at a higher risk for loosening than these in the proximal femurs without. To further improve the durability of THA, the issues of poor bone quality and structure of the hip joint should be overcome.

Brothers with genu recurvatum.

Genu recurvatum deformity is rare, usually resulting from injury to the anterior part of the proximal tibial growth plate. However, a small group of cases have no known cause. We describe brothers with the same type of this deformity on the same side. The degree of deformity differed between them, but deformities began at the same age in both (17 years) and progressed over a short period. There was no history of trauma, or other orthopaedic or genetic disorders. These features strongly suggested involvement of heritable risk factors.

Primary posterior cruciate-retaining total knee arthroplasty: a comparison of American and Japanese cohorts.

Excessive polyethylene wear is recognized as one of the most important factors affecting the durability of total knee arthroplasty; however, bearing surface wear is a multifactorial problem. The purpose of this study was to identify factors for polyethylene wear and failure in primary posterior cruciate-retaining (PCR) total knee arthroplasty (TKA) in two disparate cohorts (American and Japanese). Seventy-three total knee arthroplasty operations were performed on 48 Japanese patients, and 76 on 63 American patients with noninflammatory arthritides. All patients were evaluated clinically and radiographically using a total joint arthroplasty database. Age, weight, diagnosis, Knee Society patient category, prosthesis size, insert thickness, alignment, polyethylene wear, osteolysis, Knee Society knee score, Knee Society pain score, and radiographic and clinical survivorship were evaluated. Seventy-three Japanese TKAs were followed for a mean of 6.6 years (range, 2.0-10.6). Three (4.1%) Japanese patients required revision. Seventy-six American TKAs were followed for a mean of 9 years (range, 2-10.2). Two (2.6%) American patients required revision. The American patients were significantly older, heavier, male predominant, and required larger size implants. The Japanese patients were significantly more female predominant and had a significantly less postoperative arc of motion. Knee Society knee and pain scores, survivorship, average total polyethylene wear, and annual wear rates were not different among the two cohorts. PCR TKA had similar survivorship in disparate cohorts of Japanese and American total knee arthroplasty patients despite smaller stature patients in the Japanese cohort. Cultural, gender-specific, and morphologic differences need to be considered for knee implant design. However, survivorship and polyethylene wear rates appear to be independent of these factors in disparate populations.

[Concurrent treatment of osteoporosis including vitamin K].

The 2006 version of the guideline for prophylaxis and treatment of osteoporosis recommends vitamin K(VK)supplementation in the state of its deficiency. As VK(2) gained grade B in all aspects in the guideline, single use of the drug is limited. VK(2) may be used concurrently with other drugs in the treatment of osteoporosis. In this paper, the results of our concurrent use of two of vitamin D(3), VK(2), and EHDP are summarized, and the combined therapy including VK(2) will be reviewed.

[Hemiarthroplasty and total hip arthroplasty for idiopathic osteonecrosis of the femoral head].

Patients with idiopathic osteonecrosis of the femoral head (ION) are relatively younger (usually in their 30s to 50s) than those with osteoarthrosis (OA) , and usually have higher activity levels. When the necrotic area is large, or when advanced OA has developed, hemiarthroplasty or total hip arthroplasty (THA) are considered. When indicating these implant surgeries, age and life style of patients should be considered in selecting type of surgery and implant. In our previous study, THA was superior in durability to hemiarthroplasty in the entire series of ION patients and in the patients with stage 2 or 3 ION (without secondary OA) . As implants used for these surgeries have been improved, we are currently monitoring these implant surgeries with special interest in their durability.

[Total joint arthroplasty and bone quality--atrophic OA [osteoarthrosis] and stovepipe canal--].

Durability of total hip arthroplasty (THA) has been improved after serial innovations in prosthetic design and material and in surgical technology. Consequently, bone quality of the hip joint has emerged as an important risk factor limiting durability of a contemporary THA. Subchondral bone or eburnated bone in the acetabular roof should be preserved for the long-term durability of the socket. In atrophic osteoarthrosis (OA), i.e., OA with little osteophyte formation, prevalence of socket loosening was higher than in OA with osteophyte formation. Femoral components fixed in the proximal femur with a stovepipe canal (a wide and cylindrical canal) were more likely to develop loosening than the others. These bone-quality problems should be solved to further improve durability of THA.

[Effects of concurrent therapy for patients with osteoporosis].

In the WHO technical report, vitamin D metabolites have been suggested to have a role as an adjunctive therapy when given with an antiresorptive agent. Beneficial effects on BMD have been reported following the addition of calcitriol to alendronate, etidronate, and HRT, but no data on fracture rates are available. Here we summarize our clinical study on the concurrent therapy and review reports on the concurrent treatments.

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.

Total hip arthroplasty with bulk femoral head autograft for acetabular reconstruction in DDH. Surgical technique.

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.

[Prevention of osteoporosis around hip prosthesis using bisphosphonate].

Possible usage of bisphosphonate in total hip arthroplasty (THA) has been described. Recently, clinical efficacy of bisphosphonate in preventing stress-shielding induced disuse osteoporosis around THA has been demonstrated. Bisphosphonate is expected to improve durability of THA. However, clinical relevance of usage of bisphosphonate in THA has not been established and requires further research.

[EBM of hip protectors].

In Japan, where the population is rapidly growing older, the prevention of hip fractures is becoming increasingly important. Although bisphosphonates were reported to prevent these fractures, their effectiveness was confirmed in relatively younger elderly patients. The prevention of hip fractures, the majority of which occur in older people, may not be achieved sufficiently only by bisphosphonates, and may require other measures including the use of a hip protector. Elderly people who tend to fall, nursing-home residents, and elderly patients who have already suffered from a hip fracture are considered to be good candidates for wearing hip protectors. The main mechanism of hip fractures is falling sideways over the trochanter. Hip protectors have been developed to attenuate the impact force on the trochanter that results from falling. There have been 6 randomized clinical trials and 4 of them confirmed the efficacy of hip protectors in preventing hip fractures. The other 2 reports did not show a statistically significant efficacy, but a large number of falls occurred without wearing hip protectors. The problem of the limited adherence with their use should be solved.

[EHDP + vitamin D3 or vitamin K2].

We investigated the efficacy of concurrent use of two of 1alphaOH vitamin D(3), vitamin K(2), and EHDP in increasing lumbar BMD and in preventing new fracture in patients with primary osteoporosis. D(3) + K(2) showed little effect and was considered to be poor combination. EHDP + D(3) or EHDP + K(2) was superior to single use of these agents in both end points.

[Concurrent therapy of osteoporosis].

We investigated the efficacy of concurrent use of two of 1alphaOH vitamin D(3), vitamin K(2), and EHDP in increasing lumbar BMD and in preventing new fracture in patients with primary osteoporosis. D(3) + K(2) showed little effect and was considered to be poor combination. EHDP + D(3) or EHDP + K(2) was superior to single use of these agents in both end points. Concurrent use of anti-osteoporosis agents could be advantageous in some combination but not in another. We need more clinical data on concurrent therapy of osteoporosis.

Structural changes of the carpal tunnel, median nerve and flexor tendons in MRI before and after endoscopic carpal tunnel release.

The purpose of this study is to investigate the structural changes of the carpal tunnel, median nerve, and flexor tendons in magnetic resonance imaging (MRI) before and after endoscopic carpal tunnel release (ECTR). We studied 36 hands undergoing ECTR. In MRI, the cross-sectional area of the carpal tunnel and the median nerve at the hamate and the pisiform levels were measured. The distance from the volar side of carpal bone to the median nerve or tendons and the volar displacement were measured. In post-operative MRI, the transverse carpal ligament could not be well delineated and the carpal tunnel was significantly enlarged both at the hamate and pisiform levels. The median nerve was enlarged at the hamate level. The median nerve and flexor tendons significantly moved to the volar side. The volar displacement of the median nerve and flexor digitorum superficialis in the long and ring fingers was greater than the other tendons.

Cemented total hip arthroplasty: still relevant in the new millennium?

Total hip arthroplasty can be performed successfully using cement or cementless technology. Cemented femoral stems can achieve enduring long-term suvivorship as long as meticulous surgical technique is utilized and patient selection is appropriate. Cemented acetabular components should only be utilized in patients with less than 10 years of remaining life expectancy. Critical risk factors for cemented total hip arthroplasty include atrophic osteoarthrtis on the acetabular side and unfavorable femoral geometry for the femoral stem such as "the stove-pipe" canal. Rapid polyethylene wear and osteolysis are rarely seen in contemporary cemented total hip arthroplasty performed with a smooth, tapered, collarless femoral stem with a highly polished head and a well-designed acetabular component.