Takafumi Amano

Significantly Poor Outcomes of Total Hip Arthroplasty After Failed Periacetabular Osteotomy

BACKGROUND Periacetabular osteotomy (PAO) is an effective treatment for preosteoarthritis and early osteoarthritis in young and active patients with hip dysplasia. However, conversion to total hip arthroplasty (THA) for failed PAO is difficult owing to morphologic changes. The objective of the present study was to investigate outcomes of patients who underwent THA for failed PAO. METHODS We performed a case-control study. The participants were 48 patients (52 hips) who underwent THA after PAO (the osteotomy group); type of PAO was eccentric rotational acetabular osteotomy in 36 hips and rotational acetabular osteotomy in 16 hips. These patients had a mean age at surgery of 56.5 years and underwent postoperative follow-up for a mean period of 5.4 years. For the control group, after matching age, gender, and time of surgery, we included 96 patients (104 joints) who underwent primary THA for hip dysplasia. RESULTS The 2 groups demonstrated no significant difference in the preoperative Harris Hip Score. However, the osteotomy group demonstrated a significantly poor Harris Hip Score at the last follow-up, with particularly low scores for gait and activity. The osteotomy group demonstrated significantly poor range of motion at the last follow-up. Although neither group had any cases of revision surgery, both groups had 1 case of postoperative dislocation. Considering socket placement in Lewinneks safe zone, the osteotomy group had significantly poorer results compared to that obtained after primary THA. CONCLUSION The therapeutic outcomes and socket positioning for THA after PAO were poorer compared to those of primary THA.

Gender difference does not affect the outcomes of eccentric rotational acetabular osteotomy used in hip dysplasia

Introduction Various types of periacetabular osteotomies have been proposed to treat acetabular dysplasia for young and active patients. Acetabular dysplasia is prevalent in women and rare in men, therefore few reports exist concerning periacetabular osteotomy of male patients. The purpose of this study is to clarify the gender differences in surgical techniques, radiographic and clinical outcomes. Materials and methods Between 1989 and 2007, we performed 530 eccentric rotational acetabular osteotomies and followed them annually for more than five years. Thirty-six male patients were investigated. As a control group, 72 female patients were matched for age and preoperative stage of osteoarthritis at the time of surgery. We evaluated operative time and blood loss, radiographic parameters, Harris Hip Score (HHS) and survival rate. We investigated the clinical and radiographic differences between men and women. Results The mean operative time was 148 min in males and 135 min in females. The bleeding during surgery was 445 g in males and 351 g in females. HHS improved 94.1 points in males and 93.5 points in women postoperatively. The mean CE angle improved 31.7° in males and 35.1° in females. The mean AHI was 90.8% in males and 94.1% in females postoperatively. The survival rate of male patients were 92.8% and that of female patients were 98.1%. Conclusions The mean operative time and the blood loss were not significantly different between male and female patients. Postoperative CE angle tended to be smaller in male than female patients. The survival rate was not significantly different between males and females. Gender difference did not affect the clinical outcomes of ERAO in patients with hip dysplasia.

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.

Patient-reported outcomes in patients who undergo total hip arthroplasty after periacetabular osteotomy

BACKGROUND There has been constant discussion about whether the clinical outcome of THA after periacetabular osteotomy (PAO) is equivalent to that after primary total hip arthroplasty (THA). However, there have been few reports about patient-reported outcomes (PRO) for those who undergo THA after PAO. We compared the pre- and postoperative PRO of patients who underwent THA after PAO and those who underwent primary THA alone. METHODS We performed a case-control study. Twenty-seven patients (29 hips) underwent THA after PAO (osteotomy group); their mean age at surgery was 57.2 years, and they underwent postoperative follow-up for a mean period of 3.0 years. For the control group, after matching age, sex, and Crowe classification, we included 54 patients (58 joints) who underwent primary THA for hip dysplasia. Assessment performed preoperatively and at the last follow-up included the Harris hip score, the Short Form 36 (SF-36) for the Physical Component Summary (PCS), Mental Component Summary (MCS), and Role/Social Component Summary (RCS) domains, Japanese Orthopaedic Association Hip-Disease Evaluation Questionnaire (JHEQ) for pain, movement, and mental health, and the visual analog scale (VAS) score of hip pain and satisfaction. RESULTS The two groups demonstrated no significant difference in the preoperative Harris hip score, each domain of the SF-36, JHEQ, and the VAS score of hip pain and satisfaction. The osteotomy group demonstrated significantly poor Harris hip scores for gait and activity, and JHEQ for movement at the last follow-up. There was no significant difference in each domain of the SF-36 and the VAS score of hip pain and satisfaction at the last follow-up. CONCLUSION Previous PAO affects the quality of physical function in patients who undergo subsequent THA.

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.

The influence of early radiolucent lines appearing on femoral head penetration into HXLPE cemented sockets

Introduction: This study investigates differences in femoral head penetration between highly cross-linked polyethylene (HXLPE) cemented sockets both with and without radiolucent lines (RLLs) in the early postoperative phase and at 5 years follow-up. Methods: There were 35 patients (37 hips), mean age of 66.8 years, who underwent total hip arthroplasty (THA) using highly HXLPE cemented sockets. They were divided into 2 groups based on postoperative the early appearance of RLLs. Femoral head penetrations on both anteroposterior- and Lauenstein-view radiographs were evaluated, and the mean polyethylene (PE) wear rate was calculated based on femoral head penetrations between 2 and 5 years. Results: Femoral head penetrations in the proximal direction were 0.075 mm and 0.150 mm in the RLL and non-RLL groups at 1 year postoperatively (p = 0.019). At 5 years measured penetration was 0.107 mm and 0.125 mm in the RLL and non-RLL groups, respectively (p = 0.320). The mean PE wear rates in anteroposterior-view were 0.008 mm/year and 0.003 mm/year in the RLL and non-RLL groups (p = 0.390) and those in Lauenstein-view were 0.010 mm/year and 0.005 mm/year, respectively (p = 0.239). Conclusions: In the RLL group, the PE bedding-in was less compared with those in the non-RLL group. Additionally, the mean PE wear rate in the RLL group tended to be higher than that in the non-RLL group. The distribution of stress loading through the cement may differ according to whether early RLLs appear.

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.

Surgical education of eccentric rotational acetabular osteotomy for hip trainees

Background Periacetabular osteotomy is an excellent intervention for patients at early-stage osteoarthritis, but surgical education for this technique is more difficult than that for total hip arthroplasty. Subjects and methods 47 joints were included from patients who underwent eccentric rotational acetabular osteotomy (ERAO) performed by 6 trainees under the instructing physicians guidance. We evaluated operative time, blood loss, radiographic parameters, clinical scores, perioperative complications, and 10-year survival rates. We also compared trainees’ cases with 47 joints from patients in a sex- and age-matched control group that underwent ERAO performed by the instructing physician. Results Hip surgery trainees took an average of 152 minutes and the instructor took 103 minutes. Blood loss during surgery by the trainees and the instructor was 382 and 276 g, respectively. Postoperatively, for the trainee and instructor groups, respectively, the Harris Hip Score improved to 88.9 and 93.7 points; the average centre-edge angle improved to 34.0°and 36.1°; and the average acetabular head index was 93.9% and 95.7%. Perioperative and postoperative complications were observed in 14 patients of the trainee group and 3 patients of the instructor group, which were significantly different (p = 0.0061). The 10-year survival rates were 97.8% and 100% for the trainee and instructor groups, respectively. Conclusions Postoperative imaging evaluations showed no evident differences in coverage. Postoperative clinical outcomes were also satisfactory. Thus, under proper guidance, education to hip surgery trainees on operative techniques is possible. Instructors need to make more effort to prevent complications by providing good education.