Life Course Epidemiology of Hip Osteoarthritis in Japan: A Multicenter, Cross-Sectional Study.

BACKGROUND: The incidence of developmental dysplasia of the hip (DDH) in Japanese newborns has reduced drastically following a primary prevention campaign initiated around 1972 to 1973; this perinatal education campaign promoted maintaining the hips of newborns in the naturally flexed-leg position. The purpose of the present study was to describe the life course epidemiology of hip osteoarthritis (OA) in adolescent and adult patients and to assess its association with exposure to the primary prevention campaign for DDH. METHODS: We included new patients with hip OA diagnosed from January 1, 2022, to December 31, 2022, at 12 core hospitals (8 special-function hospitals and 4 regional medical care support hospitals). The trend in the percentage of hips with a history of DDH treatment in childhood was estimated with use of a centered moving average using the birth year of the patient. We compared the prevalence of severe subluxation (Crowe type II, III, or IV) between patients with secondary hip OA due to hip dysplasia who were born in or before 1972 and those who were born in or after 1973. RESULTS: Overall, 1,095 patients (1,381 hips) were included. The mean age at the time of the survey was 63.5 years (range, 15 to 95 years). A total of 795 patients (1,019 hips; 73.8% of hips) were diagnosed with secondary OA due to hip dysplasia. Approximately 13% to 15% of hips among patients born from 1963 to 1972 had a history of DDH treatment in childhood; however, the percentage decreased among patients born in or after 1973. The prevalence of severe subluxation (Crowe type II, III, or IV) among patients born in or after 1973 was 2.4%, which was significantly less than that among patients born in or before 1972 (11.1%; odds ratio, 0.20; p < 0.001). CONCLUSIONS: As of 2022, secondary hip OA due to hip dysplasia is still responsible for most new cases of adolescent and adult hip OA seen in core hospitals in Japan. However, the perinatal education campaign initiated 50 years ago, which utilized a population approach and advocated for maintaining the hips of newborns in the naturally flexed-leg position, may have improved the environmental factors of DDH, as indicated by the apparently reduced need for treatment of DDH in childhood and the associated severe subluxation. This may result in a reduced need for challenging hip surgery later in life. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

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.

Progression of Bone and Joint Destruction During the Perinatal Period in Patients With Rheumatoid Arthritis and Juvenile Idiopathic Arthritis in the Last Decade.

BACKGROUND: Rheumatoid arthritis (RA) is a disease that can cause joint destruction and multiple arthritis. We retrospectively investigated bone and joint destruction during the perinatal period in adult patients with RA and juvenile idiopathic arthritis (JIA) in our hospitals in the last decade. METHODS: The study included 15 women, with 20 pregnancies, 19 childbirths, and one fetal death recorded between 2009 and 2018. We analyzed patient characteristics, disease activity, the modified total Sharp score (mTSS), and ΔmTSS from prepregnancy to delivery and from delivery to one year after delivery in the biologics (BIO) group (biologics used before pregnancy) and non-BIO group (not using biologics). RESULTS: There were five preterm births and seven low-birth-weight infants. The Clinical Disease Activity Index (CDAI) before pregnancy and postdelivery worsened from 12±1.8 to 19.9±2.7 (p<0.05). The mTSS at prepregnancy and postdelivery was 47.7±12.2 and 57.3±11.1 in the BIO group, respectively, and 58.9±11.9 and 75.0±13.1 in the non-BIO group, respectively. In addition, the ΔmTSS value from prepregnancy to delivery and from delivery to one year after delivery was 14.5±4.8 and 9.2±1.7 in the BIO group, respectively (p<0.05), and 16.1±5.2 and 8.3±4.0 in the non-BIO group, respectively. CONCLUSION: The disease activity worsened, and bone and joint destruction progressed in both the BIO and non-BIO groups during the perinatal period in adult patients with RA and JIA in the last decade.

Femoral head collapse rate among Japanese patients with pre-collapse osteonecrosis of the femoral head.

OBJECTIVE: In this study, we aimed to elucidate the relationship between the duration from diagnosis to femoral head collapse and the collapse rate among patients with pre-collapse osteonecrosis of the femoral head (ONFH). METHODS: In this retrospective, observational, multicenter study, we analyzed 268 patients diagnosed with ONFH and classified them using the Japanese Investigation Committee classification. The primary endpoint was duration from the time of diagnosis to femoral head collapse for each type of ONFH. RESULTS: The 12-, 24-, and 36-month collapse rates among participants were 0%, 0%, and 0% for type A, respectively; 0%, 2.0%, and 10.8% for type B, respectively; 25.5%, 40.8%, and 48.5% for type C-1, respectively; and 57.4%, 70.3%, and 76.7% for type C-2 ONFH, respectively. A comparison of unilateral and bilateral ONFH, using Kaplan-Meier survival curves demonstrated similar collapse rates. CONCLUSIONS: The lowest collapse rate was observed for ONFH type A, followed by types B, C-1, and C-2. Additionally, a direct association was observed between the collapse rate and location of the osteonecrotic lesion on the weight-bearing surface.

Differences in subtrochanteric and diaphyseal atypical femoral fractures in a super-aging prefectural area: YamaCAFe Study.

INTRODUCTION: Atypical femoral fractures (AFFs) have been correlated with long-term use of bisphosphonates (BPs), glucocorticoids (GCs), and femoral geometry. We investigated the incidence and characteristics of subtrochanteric (ST) and diaphyseal (DP) AFFs in all institutes in a super-aging prefectural area. MATERIALS AND METHODS: We performed a blinded analysis of radiographic data in 87 patients with 98 AFFs in all institutes in Yamagata prefectural area from 2009 to 2014. Among the 98 AFFs, 57 AFFs comprising 11 ST fractures in 9 patients and 46 DP fractures in 41 patients with adequate medical records and X-rays were surveyed for time to bone healing and geometry. RESULTS: Of the 87 patients, 67 received BPs/denosumab (77%) and 10 received GCs (11%). Surgery was performed in 94 AFFs. Among 4 AFFs with conservative therapy, 3 required additional surgery. In univariate regression analyses for ST group versus DP group, male-to-female ratio was 2/7 versus 1/40, mean age at fracture was 58.2 (37-75) versus 78 (60-89) years, rheumatic diseases affected 55.5% (5/9) versus 4.9% (2/41), femoral lateral bowing angle was 1.7 (0-6) versus 11.8 (0.8-24)°, GC usage was 67% (6/9) versus 4.9% (2/41), and bone healing time was 12.1 (6-20) versus 8.1 (3-38) months (p < 0.05). In multivariate analyses, higher male-to-female ratio, younger age, greater proportion affected by rheumatic diseases, and higher GC usage remained significant (p < 0.05). CONCLUSIONS: The incidence of AFFs in our prefectural area was 1.43 cases/100,000 persons/year. This study suggests that the onset of ST AFFs have greater correlation with the worse bone quality, vice versa, the onset of DP AFFs correlated with the bone geometry. The developmental mechanisms of AFFs may differ significantly between ST and DP fractures.

Disassembly of bilateral bipolar heads within 10 years after hip hemiarthroplasties for avascular necrosis of femoral heads: a case report.

Prosthetic joint surgeries, total hip arthroplasty (THA) or bipolar hemiarthroplasty (BHA) and joint preservation surgeries can be performed for avascular osteonecrosis of femoral head (ONFH) with collapse. Although excellent surgical results have been reported, long-term survivorship and postoperative complications are a great concern. The purpose of this study was to report a case of bilateral disassembly of bipolar heads within 10 years after BHA for ONFH. A 61-year-old man, whose occupation was carpenter, underwent bilateral BHA for ONFH at another hospital when he was 57 years old. He had acute right hip pain during working and visited our institute. Radiographs revealed intra-articular (outer and inner head) disassembly of the right bipolar head, and conversion to THA was performed. Five years later, he had contralateral (left) hip pain. Radiographs revealed disassembly of bipolar head, as had occurred with the right hip, and similar conversion surgery was performed for the left hip. Marked wear and detachment of the polyethylene bearings of the outer head and failure of the locking mechanism between a skirted 22-mm-diameter inner head and polyethylene insert were observed in both hips at each revision surgery. Degeneration of the acetabulum were also observed in both hips. The failure of the self-centering mechanism because of degenerative change of the acetabulum, impingement of the outer head and neck, and high activity seemed to be the causes of disassembly of the bilateral bipolar heads. Therefore, it is important to select the type of prostheses depending on the age, activity and occupation of each patient.

Assessing an alpha-defensin lateral flow device for diagnosing septic arthritis: reporting on a false-negative case and a false-positive case.

Alpha-defensin (αD), an antimicrobial peptide released by neutrophils in response to bacterial pathogens, was proposed as a novel diagnostic biomarker in synovial fluid. Several reports have shown that αD can serve as a reliable biomarker in the diagnosis of periprosthetic joint infection (PJI). We assessed whether αD could also serve to diagnosis of septic arthritis, a similarly difficult to diagnose PJI. To our knowledge, besides PJI, few reports exist assessing the utility of αD for septic arthritis. We have attempted to diagnose several cases of suspected septic arthritis using the Synovasure® αD detection lateral flow device. We report a false-positive case and a false-negative case. The false-negative case we experienced was caused by Staphylococcus capitis, which is coagulase-negative, and possibly represents a low virulence micro-organism infection. The false-positive case was ultimately diagnosed as seronegative rheumatoid arthritis and possessed calcium pyrophosphate depositions. False positives have been suggested to occur in conditions where neutrophils are mobilised. As for PJI, in cases where diagnosis is difficult, αD can be an additional diagnostic indicator. However, making a definitive diagnosis using the αD lateral flow device alone was found to be difficult. The utility of αD in assessing septic arthritis is inconclusive; therefore, larger prospective clinical studies should be considered for a better assessment.

Rapid disappearance of gouty tophi of the foot by resection of massive gouty tophi of the opposite foot in a patient with hyperuricaemia: a case report.

Gouty tophi occur less frequently and disappear only with modern medication therapy for symptomatic or asymptomatic hyperuricaemia. However, the medication may require a long time to take effect due to the systemic urate pool associated with massive gouty tophi. We present the case of a 37-year-old woman who suffered from massive gouty tophi of both feet due to hyperuricaemia. After resection of the massive gouty tophi from her right foot and treatment with uricemia medication, the gouty tophi of her opposite foot disappeared rapidly due to reducing the patient's systemic urate pool with intensification of drug medication.

The Incidence of Atypical Femoral Fractures in Patients with Rheumatic Disease: Yamagata Prefectural Committee of Atypical Femoral Fractures (YamaCAFe) Study.

Atypical femoral fractures (AFFs) have been reported to occur with minimal or spontaneous subtrochanteric and femoral shaft fractures with a characteristic transverse pattern, compared with typical femoral fractures in young patients with high-energy trauma. AFFs are related to long-term use of bisphosphonates (BPs), glucocorticoids and rheumatic diseases. We have estimated a blind analysis of AFFs in rheumatic patients receiving BPs and glucocorticoids ordinary over a long time in all Yamagata prefectural area through radiographic examination. The 123 AFFs including suspected cases over six years were collected and reviewed by two independent orthopedic surgeons. We found 86 patients with a total of 99 AFFs between 2009 and 2014 (1.43 cases/100,000 person/year). Of these 99 AFFs, 11 were in 8 rheumatic patients including three patients with bilateral AFFs. The incidence of AFFs in rheumatic patients had trend to increase from 2012. The mean age of all 8 patients was 54.9 years. All 8 patients received BPs and 7/8 received prednisolone (PSL). The mean dose of PSL was 14 mg/day. Compared to patients with unilateral AFFs, those with bilateral AFFs in rheumatic patients were on a higher dose of PSL (20 mg/day vs. 7 mg/day) and had less femoral neck-shaft angle (129° vs. 136°, p < 0.05). In conclusion, the incidence of AFFs in rheumatic patients showed a trend to increase from 2012 to 2014 in Yamagata prefecture. Careful management of AFFs is of particular importance in rheumatic patients who have taken high doses of PSL and have small femoral neck-shaft angle.

Prevention of excessive postoperative sliding of the short femoral nail in femoral trochanteric fractures.

INTRODUCTION: Lag screw cut-out is one of the major postoperative complications on femoral trochanteric fractures. However, precise analyses of excessive sliding and lag screw cut-out were limited. The purpose of this study was to investigate the factors that induce this unfavorable event. METHODS: From April 2010 to April 2013, 226 patients were operated in our institute using a short femoral nail. Among them, 177 patients (29 males and 148 females) with a mean age of 84 years (60-97 years), who were followed up >3 months, were included in this study. The postoperative sliding distance, fracture type (AO/OTA classification), tip-apex distance (TAD), reduction pattern in the postoperative X-ray (antero-posterior and lateral views), bone quality (canal flare and cortical indices), walking ability at the time of pre-injury and final follow-up, and complications were investigated retrospectively. RESULTS: The mean sliding distance was 3.7 mm, and one cut-out case (0.6 %) was observed. The sliding distance of the AO/OTA 31-A2 fractures was significantly longer than that of the A1 fractures (p < 0.0001). Regarding the reduction pattern, the sliding distance of the intramedullary type was longer than that of the extramedullary and anatomical types in the lateral view (p < 0.01, p < 0.001, respectively). Further, even in the medial and anatomical types, where the reduction patterns are recommended in the antero-posterior view, the sliding distance of the intramedullary type was significantly longer than that of the anatomical type in the lateral view. There was no correlation of bone quality with the sliding distance. CONCLUSIONS: Because the sliding distance increased in the intramedullary type in the lateral view of unstable fractures, an accurate reduction in the lateral view at surgery is important, particularly in unstable fractures.