Daigo Komatsu

Absence of a relationship between joint space narrowing and osteophyte formation in early knee osteoarthritis among Japanese community-dwelling elderly individuals: A cross-sectional study

Abstract Objectives: Joint space narrowing and osteophyte formation, radiographic features of knee osteoarthritis (OA), are not necessarily synchronous processes. We evaluated the relationship between medial minimum joint space width (mJSW) and osteophyte formation. Methods: We conducted a retrospective study of 1050 individuals (424 males; 626 females; mean age 64.9 years) who underwent knee radiography as part of a health screening program, between 2011 and 2013. mJSW and tibial osteophyte area (OF) were quantified using automated software. The mJSW range was subdivided into tertiles, and OF, mJSW, and quality of life (QOL) were compared among them. Correlation between OF and mJSW was evaluated. Results: In females, OF was largest and correlated with mJSW only in the lowest tertile group. Patients in the lowest mJSW tertile group had a lower QOL and higher pain than those in the other two groups. Based on our generalized additive models and a receiver operating characteristic curve analysis, an mJSW cutoff point of 3.5 mm was apparent in females, with no significant cutoff identified in males. Conclusions: OF correlates with mJSW below a cutoff value of about 3.5 mm in females. OA symptoms, namely physical function impairment and pain, increases significantly as mJSW decreases below the cutoff. 

Survivorship Between 2 Different Ceramic-on-Ceramic Total Hip Arthroplasty With or Without a Metal-Backed Titanium Sleeve Bearing: A 5- to 14-Year Follow-Up Study

BACKGROUND The aim of the study was to compare the clinical and radiographic results of consecutive ceramic-on-ceramic bearings with and without a metal-backed titanium sleeve in patients undergoing total hip arthroplasty. METHODS Eighty-five patients (64 women and 21 men; average age 55.2 years) were included in the A group without sleeve while 147 patients (116 women and 31 men; average age 54.2 years) were included in the B group with sleeve. Clinical and radiologic measurements at follow-up (range, 5-14 years; average, 8.1 years) were analyzed. RESULTS The mean latest postoperative Harris Hip Score was 89.1 for patients from both groups. One joint (1.2%) in the A group displayed ceramic liner fracture, while no incidences of liner fracture occurred in the B group. Audible squeaking was observed in 1 joint (1.2%) in the A group and 1 (0.7%) in the B group. The mean annual liner rate of wear was 0.0049 and 0.0046 mm/y for the A group and B group, respectively. Three joints in the A group (3.5%) required revision total hip arthroplasty because of individual episodes of aseptic cup loosening, ceramic liner fracture, and infection. One joint in the B group (0.7%) required revision because of progressive osteolysis of the proximal femur. Ten-year Kaplan-Meier survivorship, based on an end point of component loosening and bearing failure, was 97.6% for the A group and 99.3% for the B group. CONCLUSION There were no clinical, radiographic, or survivorship differences between groups.

Incidence of Ceramic Liner Malseating After Ceramic-on-Ceramic Total Hip Arthroplasty Associated With Osteolysis: A 5- to 15-Year Follow-Up Study

BACKGROUND The aim of our study was to evaluate the clinical and radiographic outcomes of malseating of the acetabular liner in ceramic-on-ceramic total hip arthroplasty (THA). METHODS Outcomes for 160 ceramic-on-ceramic THAs, contributed by 116 women and 39 men, were evaluated. Clinical and radiographic measurements were obtained over a 5- to 15-year follow-up for analysis. RESULTS Liner malseating was identified in 20% of cases. Outcomes for 32 cases with liner malseating (group A) were compared to outcomes for 128 joints with correct liner seating (group B). The Harris hip score at the last follow-up was 90.1 for group A and 89.6 for group B. Osteolysis was identified in 5 cases in group A (15.6%), compared to 3 cases in group B (P < .001). No significant between-group differences were identified with regard to ceramic fracture, audible squeaking, loosening of components, and revision THA. The mean annual liner wear rate was comparable between groups, 0.0045 mm/y for group A and 0.0039 mm/y for group B. The 10-year Kaplan-Meier survivorship, based on an end point of revision THA, was 100% for group A and 99.0% for group B. CONCLUSION Over a moderate-length follow-up of 5-15 years, malseating of the acetabular liner was not associated with negative clinical outcomes or THA survivorship. Malseating did increase the incidence of osteolysis, a risk factor for adverse effects. Long-term follow-up studies are needed to fully quantify the effects of malseating of the acetabular liner.

The poor quality and reliability of information on periacetabular osteotomy on the internet in Japan

ABSTRACT Although many patients use the internet to access health-related information, the quality and the reliability of the information is highly inconsistent. Periacetabular osteotomy (PAO) is one of the surgical procedures for hip dysplasia. However, medical information on PAO is limited on the internet. This study aims to evaluate the quality and reliability of information available on PAO on the internet in Japan. A web search was conducted on two search engines for the following terms: “hip osteotomy,” “pelvic osteotomy,” and “osteotomy for hip preservation” in Japanese. In total, we found 120 websites. To determine the quality and reliability of information on each website, we used the Health on the Net Foundation (HON) score, the Brief DISCERN score, and an osteotomy-specific content (OSC) score. After eliminating duplicate websites, we reviewed 49 unique websites. Only three websites (6.1%) had good reliability, as indicated by their HON scores. Twelve websites (24.4%) had good-quality information, as measured by their Brief DISCERN scores. As evaluated by their OSC scores, physician websites were found to be biased toward etiology and surgical indication and did not provide information on the complications of procedures. Non-physician websites were generally insufficient. The information about PAO on the internet is, therefore, unreliable and of poor-quality for Japanese patients.

Independent association of joint space narrowing, cyst formation and health-related quality of life of patients with hip osteoarthritis in Japan

INTRODUCTION This study clarified individual associations of joint space narrowing (JSN) and radiographic features (RF) of hip osteoarthritis (HOA), i.e., cyst and osteophyte formation and subchondral sclerosis, with quality of life (QOL) in Japanese HOA patients. METHODS This cross-sectional study comprised 117 Japanese HOA patients (98 women, 17 men; mean age, 61.2 years). We recorded locations and the size of each RF and measured JSN on the acetabular side (Ace) or femoral head (FH). We evaluated pain with the Visual Analog Scale (VAS) and assessed QOL with the physical component summary (PCS) and mental component summary (MCS) of the Medical Outcomes Study Short Form-36. We compared QOL with/without the RF on the Ace, FH or both and analyzed relationships between each RF and VAS, PCS and MCS with linear regression analysis. We assessed independent associations of each RF with PCS and MCS with multiple regression analysis using various independent variables. RESULTS VAS values with the cyst on the Ace only were significantly lower than those with the cyst at both locations. PCS values with the cyst on the Ace only were significantly higher than those for both locations. Independent associations existed for maximum cyst length on the Ace and FH with VAS and for JSN with PCS, but none existed for MCS. CONCLUSIONS Our study suggested that the location and the size of the cyst formation were associated with both VAS and QOL in Japanese HOA patients. The JSN was independently associated with the PCS.

Validity of radiographic assessment of the knee joint space using automatic image analysis

Abstract Objectives: The present study investigated whether there were differences between automatic and manual measurements of the minimum joint space width (mJSW) on knee radiographs. Methods: Knee radiographs of 324 participants in a systematic health screening were analyzed using the following three methods: manual measurement of film-based radiographs (Manual), manual measurement of digitized radiographs (Digital), and automatic measurement of digitized radiographs (Auto). The mean mJSWs on the medial and lateral sides of the knees were determined using each method, and measurement reliability was evaluated using intra-class correlation coefficients. Measurement errors were compared between normal knees and knees with radiographic osteoarthritis. Results: All three methods demonstrated good reliability, although the reliability was slightly lower with the Manual method than with the other methods. On the medial and lateral sides of the knees, the mJSWs were the largest in the Manual method and the smallest in the Auto method. The measurement errors of each method were significantly larger for normal knees than for radiographic osteoarthritis knees. Conclusions: The mJSW measurements are more accurate and reliable with the Auto method than with the Manual or Digital method, especially for normal knees. Therefore, the Auto method is ideal for the assessment of the knee joint space.

Comparison of cementless total hip arthroplasty survivorship between metal-on-highly cross-linked polyethylene and ceramic on ceramic bearings: A case control study with a 5-9-year follow-up

BACKGROUND Currently, there is a lack of evidence on the medium-term follow-up of cementless total hip arthroplasty (THA) using metal-on-highly cross-linked polyethylene bearing (MoXPE), ceramic on ceramic bearing (CoC) at more than 5 years follow-up. Therefore, we performed a case control study to: compare the incidence rate of osteolysis; compare the longevity for both types of THAs, and to evaluate the wear rate of MoXPE THAs. HYPOTHESIS CoC THAs will have a lower rate of osteolysis and better longevity than MoXPE THAs. PATIENTS AND METHODS We performed a retrospective analysis of 77 MoXPE (68 women, 9 men) and 105 CoC (85 women, 20 men) THAs, with an average patient age at the time of surgery of 64.7 years (range, 27 to 76 years). The cohorts were matched according to sex, body mass index, or diagnosis of hip joint disease. Clinical and radiologic measurements were analyzed at a mean follow-up of 6.7 years (range, 5-9 years). RESULTS There were no between-group differences with regard to the Harris hip score (87.0 [64.0-98.0] and 89.9 [70.0-100.0] for the MoXPE and CoC group, respectively) and the incidence rate of osteolysis (2.6% and 1.9%, respectively). Revision was required for 1 case for each THA type. The Kaplan-Meier survival at 8 years, using implant loosening or revision as the end-point of analysis, was 96.1% (95% confidence interval [CI], 90.0-99.3) for the MoXPE group and 98.9% (95% CI, 92.2-99.8) for the CoC group (p=0.189). The mean annual liner wear rate was 0.0160mm/year (range, 0.0050 to 0.0390mm/year) for the MoXPE THAs. DISCUSSION There was no difference between CoC and MoXPE THAs in the incidence of osteolysis or in survival rate at 8 years post-surgery. Excellent clinical and radiological outcomes were obtained for both types of bearings. LEVEL OF EVIDENCE III, Case control study, case control retrospective design.

Laterality of radiographic osteoarthritis of the knee.

ABSTRACT There are few reports of the laterality in radiological knee osteoarthritis (ROA). This study aimed to evaluate laterality in terms of the minimum joint space width (mJSW) and osteophyte areas (OFs) in a cross-sectorial general population screen and elucidate the association between laterality and risk of osteoarthritis. We enrolled 330 participants (mean age 64.6 years) and examined the presence of ROA (Kellgren–Lawrence grade ≧ 2) laterality in terms of the mJSW and OF on the medial tibia using auto-measuring software. Moreover, we examined the association between laterality and leg dominance. The right and left medial mJSWs were 4.02 ± 0.98 mm and 4.05 ± 1.01 mm, respectively, showing no laterality; the laterals were also similar. The participants who had osteophytes ≥1 mm2 in the right, left, and bilateral knees were 15, 37, and 57 respectively, with osteophytes being significantly more common in the left knee. The OF was significantly larger in the left knee. Conversely, the medial and lateral mJSWs and OF did not differ according to leg dominance. The prevalence of ROA was higher and the OF was more pronounced in the left knee. However, the mJSW showed no laterality. Additionally, the mJSW and OF showed no differences according to leg dominance.