Large language model may assist diagnosis of SAPHO syndrome by bone scintigraphy.

OBJECTIVE: In this study, we employed a large language model to evaluate the diagnostic efficacy of radiology reports of bone scintigraphy in the context of identifying SAPHO syndrome, and further examined the potential of such a model to augment the diagnostic procedure. METHODS: Imaging data and clinical information of 151 patients (105/46 women/men, mean age: 53.5 years) who underwent bone scintigraphy for suspected SAPHO syndrome between January 2007 and December 2022 were retrospectively reviewed. ChatGPT-4.0 was used as the large language model. The diagnostic performance of the large language model was verified by comparing the cases judged to have SAPHO syndrome that fulfilled Kahn's classification criteria based on a combination of concise radiology reports and skin lesions such as palmoplantar pustulosis, with cases diagnosed with SAPHO syndrome by rheumatologists based on all clinical information. The diagnostic performance of the large language model was verified. RESULTS: The diagnostic accuracy of a large language model for analyzing bone scintigraphy radiology reports in conjunction with information about skin symptoms, such as palmoplantar pustulosis, achieved a sensitivity of 83.5%, specificity of 69.4%, and an overall accuracy of 76.8%. DISCUSSION: While this research is an initial endeavor dedicated to the utilization of a substantial language model in the creation of a database for imaging diagnostics of rheumatic conditions, it exhibits commendable diagnostic accuracy, particularly for diseases with a wide range of symptoms like SAPHO syndrome, indicating a positive outlook for subsequent studies. CONCLUSION: This research indicates the prospective value of extensive language models in scrutinizing radiology accounts from bone scintigraphy for the diagnosis of SAPHO syndrome.

Pyoderma gangrenosum after surgery for forefoot deformity in a patient with rheumatoid arthritis: A case report.

Pyoderma gangrenosum (PG) is a rare inflammatory skin disease characterised by skin ulcers that are associated with autoimmune diseases. Although the effectiveness of immunosuppression with glucocorticoids and tumour necrosis factor inhibitors in treating PG has been reported, the utility of negative-pressure wound therapy (NPWT) for severe ulcerative lesions in patients with PG remains controversial. Herein, we report the case of a 76-year-old woman with rheumatoid arthritis who developed PG after undergoing surgery for a forefoot deformity. The patient showed improvement in deep ulcer lesions through NPWT while receiving treatment with abatacept and systemic glucocorticoids. Subsequent topical glucocorticoid therapy led to the remission of the PG. This case suggests that NPWT, when used under immunosuppressive conditions, does not exacerbate the pathergy and may be beneficial for treating severe ulcerative PG.

Assessment of clinical and radiological characteristics of Japanese patients with SAPHO syndrome.

OBJECTIVE: This study aimed to analyse the radiological characteristics and clinical diversity of Japanese patients with synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome, a heterogeneous disorder. METHODS: Radiographs and clinical information from 115 Japanese patients (female/male: 81/34, mean age at onset: 48.7 years) diagnosed with SAPHO syndrome between January 2007 and December 2020 were retrospectively reviewed. Additionally, the treatment for SAPHO syndrome was explored. RESULTS: Among the 115 patients, 70 patients had complications, including palmoplantar pustulosis, acne, or psoriasis. Imaging studies included bone scintigraphy, magnetic resonance imaging, computed tomography, and positron emission tomography in 71, 58, 70, and 23 patients, respectively. The most frequent lesions were arthritis and hyperostosis of the sternoclavicular joints in 96 patients; spinal lesions, including sacroiliac arthritis were observed in 85 patients. Peripheral aseptic osteitis was observed in 22 patients, and the tibia was involved in 12. The treatments consisted of analgesics, bisphosphonates, conventional synthetic disease-modifying anti-rheumatic drugs, and biologics (tumour necrosis factor inhibitors and interleukin-23p19 inhibitors) in 85, 15, 23, and 10 patients (8 and 2 patients), respectively. CONCLUSION: Sternoclavicular hyperostosis and pustulosis are frequently observed in patients with SAPHO syndrome. Biological agents were more frequently used in patients with peripheral osteitis and arthritis.

Long-term results of Chiari pelvic osteotomy on the preservation of hip function with mean follow-up of more than 30 years and its prognostic factors.

BACKGROUND: Clinical outcomes of Chiari pelvic osteotomy for acetabular dysplasia, including conversion to total hip arthroplasty (THA), have not been adequately explored. The purpose of this study was to examine the long-term results and clinical outcomes of Chiari pelvic osteotomy as the primary outcome and to analyze its prognostic factors as the second outcome. METHODS: This study was a multicenter, retrospective cohort study. Ninety-seven patients underwent Chiari pelvic osteotomy at three hospitals between March 1975 and October 1997. The long-term clinical outcomes of Chiari pelvic osteotomy, including conversion to THA and hip pain, were analyzed using the Kaplan-Meier method. In addition, the prognostic factors for conversion to THA after Chiari pelvic osteotomy were evaluated with clinical variables and radiographic parameters. RESULTS: The study included 51 hips in 45 patients (4 men and 41 women) with long-term follow-up. The survival rates assessed by Kaplan-Meier analysis with conversion to THA as an endpoint, were 90.2% (95% confidence interval (CI) 82.0-98.4%) at 20 years and 73.5% (95% CI 61.1-86.0%) at 30 years. In contrast, the Kaplan-Meier survival rates with the Japanese Orthopaedic Association hip score for pain ≤20 as an endpoint, were 86.3% (95% CI 76.8-95.7%) at 20 years and 65.6% (95% CI 52.3-79.0%) at 30 years. Only older age at osteotomy was the significantly poor prognostic factor for conversion to THA, with a hazard ratio of 1.11/year, 95% CI 1.06 to 1.18, (p < 0.01). CONCLUSION: Chiari pelvic osteotomy may still be a good alternative to bony reconstructive surgery for acetabular dysplasia especially in young patients. Only older age at the osteotomy was related to the poor prognosis of preserving hip function.

Octacalcium Phosphate/Gelatin Composite (OCP/Gel) Enhances Bone Repair in a Critical-sized Transcortical Femoral Defect Rat Model.

BACKGROUND: Bone grafting is widely used to treat large bone defects. A porous composite of a bioactive octacalcium phosphate material with gelatin sponge (OCP/Gel) has been shown to biodegrade promptly and be replaced with new bone both in animal models of a membranous bone defect and a long bone defect. However, it is unclear whether OCP/Gel can regenerate bone in more severe bone defects, such as a critical-size transcortical defect. QUESTIONS/PURPOSES: Using an in vivo rat femur model of a standardized, transcortical, critical-size bone defect, we asked: Compared with a Gel control, does OCP/Gel result in more newly formed bone as determined by (1) micro-CT evaluation, (2) histologic and histomorphometric measures, and (3) osteocalcin staining and tartrate-resistant acid phosphatase staining? METHODS: Thirty-four 12-week-old male Sprague-Dawley rats (weight 356 ± 25.6 g) were used. Gel and OCP/Gel composites were prepared in our laboratory. Porous cylinders 3 mm in diameter and 4 mm in height were manufactured from both materials. The OCP/Gel and Gel cylinders were implanted into a 3-mm-diameter transcortical critical-size bone defect model in the left rat femur. The OCP/Gel and Gel were randomly assigned, and the cylinders were implanted. The biological responses of the defect regions were evaluated radiologically and histologically. At 4 and 8 weeks after implantation, CT evaluation, histological examination of decalcified samples, and immunostaining were quantitatively performed to evaluate new bone formation and remaining bone graft substitutes and activity of osteoblasts and osteoclast-like cells (n = 24). Qualitative histological evaluation was performed on undecalcified samples at 3 weeks postimplantation (n = 10). CT and decalcified tissue analysis was not performed blinded, but an analysis of undecalcified specimens was performed under blinded conditions. RESULTS: Radiologic analysis revealed that the OCP/Gel group showed radiopaque regions around the OCP granules and at the edge of the defect margin 4 weeks after implantation, suggesting that new bone formation occurred in two ways. In contrast, the rat femurs in the Gel group had a limited radiopaque zone at the edge of the defect region. The amount of new bone volume analyzed by micro-CT was higher in the OCP/Gel group than in the Gel group at 4 and 8 weeks after implantation (​​4 weeks after implantation: OCP/Gel versus Gel: 6.1 ± 1.6 mm 3 versus 3.4 ± 0.7 mm 3 , mean difference 2.7 [95% confidence interval (CI) 0.9 to 4.5]; p = 0.002; intraclass correlation coefficient [ICC] 0.72 [95% CI 0.29 to 0.91]; 8 weeks after implantation: OCP/Gel versus Gel: 3.9 ± 0.7 mm 3 versus 1.4 ± 1.1 mm 3 , mean difference 2.5 [95% CI 0.8 to 4.3]; p = 0.004; ICC 0.81 [95% CI 0.47 to 0.94]). Histologic evaluation also showed there was a higher percentage of new bone formation in the OCP/Gel group at 4 and 8 weeks after implantation (​​4 weeks after implantation: OCP/Gel versus Gel: 31.2% ± 5.3% versus 13.6% ± 4.0%, mean difference 17.6% [95% CI 14.2% to 29.2%]; p < 0.001; ICC 0.83 [95% CI 0.53 to 0.95]; 8 weeks after implantation: OCP/Gel versus Gel: 28.3% ± 6.2% versus 9.5% ± 1.9%, mean difference 18.8% [95% CI 11.3% to 26.3%]; p < 0.001; ICC 0.90 [95% CI 0.69 to 0.97]). Bridging of the defect area started earlier in the OCP/Gel group than in the Gel group at 4 weeks after implantation. Osteocalcin immunostaining showed that the number of mature osteoblasts was higher in the OCP/Gel group than in the Gel group at 4 weeks (OCP/Gel versus Gel: 42.1 ± 6.5/mm 2 versus 17.4 ± 5.4/mm 2 , mean difference 24.7 [95% CI 16.2 to 33.2]; p < 0.001; ICC 0.99 [95% CI 0.97 to 0.99]). At 4 weeks, the number of osteoclast-like cells was higher in the OCP/Gel composite group than in the Gel group (OCP/Gel versus Gel: 3.2 ± 0.6/mm 2 versus 0.9 ± 0.4/mm 2 , mean difference 2.3 [95% CI 1.3 to 3.5]; p < 0.001; ICC 0.79 [95% CI 0.35 to 0.94]). CONCLUSION: OCP/Gel composites induced early bone remodeling and cortical bone repair in less time than did the Gel control in a rat critical-size, transcortical femoral defect, suggesting that OCP/Gel could be used as a bone replacement material to treat severe bone defects. CLINICAL RELEVANCE: In a transcortical bone defect model of critical size in the rat femur, the OCP/Gel composite demonstrated successful bone regeneration. Several future studies are needed to evaluate the clinical application of this interesting bone graft substitute, including bone formation capacity in refractory fracture and spinal fusion models and the comparison of bone strength after repair with OCP/Gel composite to that of autologous bone.

Sacral Stress Fracture following the Bone Union of Lumbar Spondylolysis.

While 22 articles have reported on sacral stress fractures, it is a rare injury and its etiology is not well known. We present the case of a 16-year-old male who presented with low back pain in 2015. He was a high school soccer player with a previous history of a bilateral L5 lumbar spondylolysis in 2014. The patient refrained from soccer and wore a brace for six months. Two months after restarting soccer, he again complained of low back pain. After 1 year, a lumbar spine computed tomography revealed the bone union of the spondylolysis. At his first visit to our hospital, his general and neurological conditions were normal and laboratory data were within the normal range. Sacral coronal magnetic resonance imaging (MRI) of the left sacral ala revealed an oblique lineal signal void surrounding bone marrow edema. Based on his symptoms, sports history, and MRI, he was diagnosed with a sacral stress fracture. He again refrained from soccer; his low back pain soon improved, and, after 1 year, the abnormal signal change had disappeared on sacral MRI. Recurrent low back pain case caused by a sacral stress fracture occurring after the bone union of lumbar spondylolysis is uncommon.