アテロコラーゲンゲル包埋細切軟骨片の単離軟骨細胞に対する細胞増殖能、遊走能における有用性の検討

内容の要旨, 審査の要旨広島大学(Hiroshima University)博士(医学)Doctor of Philosophy in Medical Sciencedoctora

Evaluation of articular cartilage injury using computed tomography with axial traction in ankle joint

Category: Ankle Introduction/Purpose: Although chondral or osteochondral injuries are usually assessed by MRI, its accuracy is reportedly low because of the relatively thin cartilage layer and its close apposition to the cartilage talus and tibial plafond. The subchondral bone plays a role in cartilage metabolism, therefore the evaluation of subchondral bone is crucial for cartilage treatment. A method which enables the simultaneous evaluation of cartilage and subchondral bone is useful for the treatment of cartilage injury. The purpose of this study was to assess the feasibility of CT imaging with axial traction for the diagnosis of articular cartilage injuries. Methods: Chondral lesion in 18 ankles of 17 patients were evaluated. These 18 ankles consisted of 11 ankles of osteochondral lesion of the talar dome (OLT), 5 ankles of osteoarthritis of ankle joints and 2 ankles of anterior impingement syndrome. Twelve males and 5 women were included, with a mean age of 33.7 years (range, 15 -70 years). An ankle distractor foot strap was placed on the ankle with 30 degrees flexion of the knee joint, and a traction force of 80 N was applied during CT scanning. Gray scale CT images were allocated colors to make it easier to evaluate the cartilage layer. The international Cartilage Repair Society (ICRS) grades on CT were compared with those in arthroscopic findings. Results: The respective sensitivity and specificity of CT imaging with traction compared to ICRS grading were 74.4%, and 96.3%. The level of agreement of the ICRS grading between CT images and arthroscopic findings showed moderate (kappa coefficient; 0.547). The diagnosis of grade 3 or 4 lesions had 80.0% sensitivity. Axial traction to CT enabled the delineation of the cartilage surface including chondral thinning, defect and cartilage separation more visible (Figure 1). Conclusion: CT with axial traction could obtain acceptable levels of sensitivity and specificity for the evaluation of articular cartilage injuries in addition to the assessment of subchondral bone

Outcome of Autologous Bone Grafting with Preservation of Articular Cartilage to Treat Osteochondral Lesions of the Talus with Large Subchondral Cysts

Category: Ankle Introduction/Purpose: Treatment options for osteochondral lesion of the talus (OLT) have substantially increased over the last decade. There are a wide variety of surgical treatments for OLT, and good clinical results have been reported. However, treatment for OLT with large subchondral bone cysts remains under discussion. The combination of autologous bone grafting for subchondral bone cyst with fixation of articular cartilage would be the desirable procedure for the repair of the large subchondral cyst preserving the original cartilage with native structure and geometry. The purpose of this study is to evaluate the clinical outcome of autologous cancellous bone graft and fixation of cartilage fragment for OLT with large subchondral cysts. Methods: Patients comprised seven men and five women, aged 14–70 (mean 35.9) years. All OLTs included full-thickness articular cartilage, extended through subchondral bone and were associated with subchondral cysts. The mean size of the cysts was 9 ×8.6 ×12.3 mm on preoperative CT. Medial lesions were exposed through an oblique medial malleolar osteotomy; lateral lesions through expansion of an anterolateral arthroscopic portal. After refreshed the subchondral cyst, it was grafted with autologous cancellous bone from the distal tibial metaphysis, then cartilage fragments were fixed with nylon suture to surrounding cartilage. Postoperative MRI and CT scans were acquired for all patients at one year after surgery. Seven patients requested screw removal although none had symptoms. The screws were removed and simultaneous arthroscopic examination was performed at 1.5–2 years after surgery with the patients’ permission. The cartilage repair was assessed according to the criteria of the International Cartilage Repair Society (ICRS). Results: Functional outcome was evaluated at 25.3 (15–50) months after surgery. Mean American Orthopedic Foot and Ankle Society ankle-hindfoot outcome score improved from 65.7 to 92 (90–100) postoperatively, with 100% patient satisfaction. All follow-up CT scans showed that the grafts were well consolidated with the surrounding subchondral bone. On MRI one year after surgery, no scans showed any signs of osteochondral graft instability. The mean ICRS arthroscopic score from follow-up arthroscopy was 11.1 (8–12) points, and represented nearly normal cartilage. Conclusion: Our study demonstrated good results of autologous bone grafting in preserving articular cartilage in cases of symptomatic OLT with subchondral cysts. In seven cases, we performed follow-up arthroscopy at 1.5–2 years after primary operation and the chondral fragment showed a smooth surface and good stability. The technique of autologous bone grafting with chondral fragment fixation could be a promising option for treatment of OLT with subchondral cysts

New screening method for hallux valgus with using smartphone

Category: Midfoot/Forefoot Introduction/Purpose: We developed a new screening method for hallux valgus during weight bearing using the photo-capturing function in cell phones. Methods: We compared apparent hallux valgus angles measured from photographs of people in a standing position during weight bearing, which were captured on a smartphone (smartphone Hallux Valgus Angle: SP-HVA) (Smartphone Method), with hallux valgus angles determined using conventional radiography in a standing posture during weight-bearing (X-ray HVA: XR-HVA). We evaluated 37 feet of 25 patients (5 men and 25 women) who visited our hospital. The mean age at the time of the visit was 73.9 years. In the Smartphone Method, subjects stood upright and the examiner used a smartphone to take photos of both feet from above while holding the phone at the level of the anterior knee. Results: The mean value was 36.2° for SP-HVA and 36.7° for XR-HVA; the two methods showed a statistically significant correlation (correlation coefficient of 0.86). Conclusion: Our smartphone-assisted screening method for hallux valgus was possible to make a diagnosis equivalent to conventional radiography method without radiation exposure