Japanese orthopaedic association (JOA) clinical practice guidelines on the management of malignant bone tumors - Secondary publication.

BACKGROUND: In Japan, there are currently no general guidelines for the treatment of primary malignant bone tumors. Therefore, the Japanese Orthopaedic Association established a committee to develop guidelines for the appropriate diagnosis and treatment of primary malignant bone tumors for medical professionals in clinical practice. METHODS: The guidelines were developed in accordance with "Minds Clinical Practice Guideline Development Handbook 2014″ and "Minds Clinical Practice Guideline Development Manual 2017". The Japanese Orthopaedic Association's Bone and Soft Tissue Tumor Committee established guideline development and systematic review committees, drawing members from orthopedic specialists leading the diagnosis and treatment of bone and soft tissue tumors. Pediatricians, radiologists, and diagnostic pathologists were added to both committees because of the importance of multidisciplinary treatment. Based on the diagnosis and treatment algorithm for primary malignant bone tumors, important decision-making points were selected, and clinical questions (CQ) were determined. The strength of recommendation was rated on two levels and the strength of evidence was rated on four levels. The recommendations published were selected based on agreement by 70% or more of the voters. RESULTS: The guideline development committee examined the important clinical issues in the clinical algorithm and selected 22 CQs. The systematic review committee reviewed the evidence concerning each CQ and a clinical value judgment was added by experts. Eventually, 25 questions were published and the text of each recommendation was determined. CONCLUSION: Since primary malignant bone tumors are rare, there is a dearth of strong evidence based on randomized controlled trials, and recommendations cannot be applied to all the patients. In clinical practice, appropriate treatment of patients with primary malignant bone tumors should be based on the histopathological diagnosis and degree of progression of each case, using these guidelines as a reference.

Addition of a Vascular Bundle Accelerates Bone Union in Femoral Bone Defects.

BACKGROUND: The Masquelet method has become increasingly popular for the treatment of bone defects in recent years. In this method, an induced membrane (IM) with abundant blood circulation, stem cells, and osteogenesis-promoting factors is formed by implanting bone cement during the first surgery. This IM stimulates bone formation in the bone defect after implantation of the bone graft during the second surgery. However, the Masquelet method requires two surgeries and thus a longer treatment period. In the present study, we investigated whether bone defects could be reconstructed in a single surgery by introducing a vascular bundle into the bone defect as an alternative to the IM, in addition to bone grafting. METHODS: Thirty-six 12-week-old female Sprague-Dawley rats were used. After creating a 5-mm long bone defect in the femur, a mixture of autologous and artificial bone was grafted into the defect, and a saphenous arteriovenous vascular bundle was introduced. The animals were divided into three groups: the control group (bone defect only), the BG group (bone grafting only), and the BG + V group (bone grafting + vascular bundle introduction). After surgery, radiological and histological evaluations were performed to assess osteogenesis and angiogenesis in bone defects. RESULTS: In the BG + V group, significant bone formation was observed in the bone defect on radiological and histological evaluations, and the amount of bone formation was significantly higher than that in the other two groups. Furthermore, cortical bone continuity was observed in many specimens in the BG + V group. On histological evaluation, the number of blood vessels was also significantly higher in the BG + V group than in the other two groups. CONCLUSION: Our results suggest that the introduction of a vascular bundle in addition to bone grafting can promote bone formation in bone defects and allow for complete bone defect reconstruction in a single surgery.

More than 20 years' follow-up of metatarsal neck shortening oblique osteotomy for rheumatoid forefoot deformity.

BACKGROUND: In recent years, advances in pharmacotherapy for rheumatoid arthritis (RA) have dramatically improved the control of disease activity. However, a significant number of patients still develop forefoot deformity. The purpose of this study was to investigate the results of more than 20 years' follow-up of metatarsal neck shortening oblique osteotomy (SOO) for forefoot deformity in patients with RA. METHODS: The metatarsal neck SOO was performed on 163 feet in 108 patients between January 1985 and December 1996 in the authors' hospital. For the patients, who met the survey criteria, an observational study was performed clinically and radiologically at the baseline and at more than 20 years after surgery. RESULTS: A retrospective cohort study was conducted on 36 feet in 22 patients, all of whom were female, and the mean age at surgery was 45.6 (35.0-63.0) years old. The follow-up period was 25.1 (21.0-31.0) years. The presence of painful callosities in the surgically treated feet without revised surgeries decreased from 32 feet (100%) to 4 feet (12.5%) at the last follow-up with mild pain that did not cause any footwear problems. Re-osteotomy at the metatarsal of the lessor toe was performed on four feet in two patients. Radiologically, among 128 toes without revised surgeries, 85% were able to have the joint space preserved, and 89% maintained a pain-free condition without any recurrence of deformity. The mean total Japanese Society for Surgery for the Foot (JSSF) RA foot and ankle score was 64.0/100, and the visual analogue scale (VAS) of overall satisfaction was 62 (0: dissatisfied, 100: highly satisfied). The overall satisfaction had a positive correlation with calcaneal pitch and negative correlation with joint space narrowing at the talocrural joint. CONCLUSIONS: Metatarsal neck SOO appeared to be effective for patients with RA. The deformity was corrected and retained for a long time.

Perioperative Clinical Course Variables Associated with Length of Hospital Stay after Primary Intracranial Meningioma Resection.

The relationship between perioperative clinical course variables and postoperative length of hospital stay (LOS) in patients undergoing primary intracranial meningioma resection has not been fully elucidated. We therefore aimed to identify the perioperative clinical course variables that predict postoperative LOS in such patients. We retrospectively collected data concerning demographics, tumor characteristics, and perioperative clinical course variables in 76 patients who underwent primary intracranial meningioma resection between January 2010 and December 2019, and tested for associations with postoperative LOS. Univariate analyses showed that younger age, fewer days to postoperative initiation of standing/walking, preoperative independence in activities of daily living (ADL), and ADL independence one week after surgery were associated with shorter postoperative LOS. Multiple regression analyses with these factors identified that days to stand/walk initiation and ADL independence one week after surgery were associated with postoperative LOS. Based on these results, we conclude that rehabilitation programs that promote early mobilization and the early acquisition of independence may reduce postoperative LOS in patients who undergo primary intracranial meningioma resection.

Skin extension with a digito-lateral flap and early active finger extension training for Dupuytren contracture: A retrospective study.

In the surgical management of Dupuytren contracture (DC), Y-V plasty (YV) and Z-plasty (ZP) are techniques often used for skin extension. However, achieving sufficient skin extension with these procedures alone is often difficult. Therefore, we addressed this issue with an adjunctive digito-lateral flap (DLF) and report the clinical results of the surgery using a DLF in addition to YV and ZP. Fifteen patients with DC (15 affected fingers) underwent partial fasciectomy using a DLF in addition to YV or ZP, and early active finger extension training was performed immediately after the operation. The flap survival rate, preoperative and postoperative extension angle, Tonkin contracture improvement (TCI) rate, and Tubiana staging grades were evaluated. The contracture sites were at 4 proximal interphalangeal (PIP) and 3 metacarpophalangeal (MP) joints of the little finger and 4 PIP and MP joints each of the ring and little fingers. All the flaps survived, and the extension angle improved at the final observation from a preoperative mean of -45° to -3° and -55° to 5° for the PIP and MP joints, respectively. One patient with PIP joint contracture treated in the early stage of the study experienced a persistent 5° limitation of extension, even though the TCI rate was satisfactory (91.9%) and the outcome was "good." Full extension of the joints was achieved in 15 patients, in whom the TCI rate was 100% and the outcome was "very good." This technique was able to solve 3 important steps to achieve full extension: intraoperatively, wound closure, and rehabilitation. We attained and maintained long-term full extension intraoperatively and immediately after surgery and obtained very good treatment results, as shown in this study. In conclusion, highly favorable clinical outcomes were achieved through the combination of a DLF with YV and ZP. Skin extension with a DLF is a useful surgical technique for DC.

Total hip arthroplasty after rotational acetabular osteotomy for developmental dysplasia of the hip: a retrospective observational study.

BACKGROUND: Total hip arthroplasty after osteotomy is more technically challenging than primary total hip arthroplasty, especially concerning cup placement. This is attributed to bone morphological abnormalities caused by acetabular bone loss and osteophyte formation. This study aimed to investigate the clinical and radiological outcomes of total hip arthroplasty after rotational acetabular osteotomy compared with those of primary total hip arthroplasty, focusing mainly on acetabular deformity and cup position. METHODS: The study included 22 hips that had undergone rotational acetabular osteotomy and 22 hips in an age- and sex-matched control group of patients who underwent total hip arthroplasties between 2005 and 2020. We analyzed cup abduction and anteversion; lateral, anterior, and posterior cup center-edge angle; hip joint center position; femoral anteversion angle; and presence of acetabular defect using postoperative radiography and computed tomography. Operative results and clinical evaluations were also analyzed. RESULTS: The clinical evaluation showed that the postoperative flexion range of motion was lower in total hip arthroplasty after rotational acetabular osteotomy than in primary total hip arthroplasty, although no significant difference was noted in the postoperative total Japanese Orthopedic Association hip score. The operative time was significantly longer in the rotational acetabular osteotomy group than in the control group, but there was no significant difference in blood loss. The lateral cup center-edge angle was significantly higher and the posterior cup center-edge angle was significantly lower in the total hip arthroplasty after rotational acetabular osteotomy, suggesting a posterior bone defect existed in the acetabulum. In total hip arthroplasty after rotational acetabular osteotomy, the hip joint center was located significantly superior and lateral to the primary total hip arthroplasty. CONCLUSIONS: In total hip arthroplasty after rotational acetabular osteotomy, the cup tended to be placed in the superior and lateral positions, where there was more bone volume. The deformity of the acetabulum and the high hip center should be considered for treatment success because they may cause cup instability, limited range of motion, and impingement.

Perioperative Adriamycin plus ifosfamide vs. gemcitabine plus docetaxel for high-risk soft tissue sarcomas: randomised, phase II/III study JCOG1306.

BACKGROUND: This randomised phase II/III trial aimed to determine whether perioperative chemotherapy with gemcitabine plus docetaxel (GD) is non-inferior to the standard Adriamycin plus ifosfamide (AI) in terms of overall survival (OS) in patients with soft tissue sarcoma (STS). METHODS: Patients with localised high-risk STS in the extremities or trunk were randomised to receive AI or GD. The treatments were repeated for three preoperative and two postoperative courses. The primary endpoint was OS. RESULTS: Among 143 enrolled patients who received AI (70 patients) compared to GD (73 patients), the estimated 3-year OS was 91.4% for AI and 79.2% for GD (hazard ratio 2.55, 95% confidence interval: 0.80-8.14, P = 0.78), exceeding the prespecified non-inferiority margin in the second interim analysis. The estimated 3-year progression-free survival was 79.1% for AI and 59.1% for GD. The most common Grade 3-4 adverse events in the preoperative period were neutropenia (88.4%), anaemia (49.3%), and febrile neutropenia (36.2%) for AI and neutropenia (79.5%) and febrile neutropenia (17.8%) for GD. CONCLUSIONS: Although GD had relatively mild toxicity, the regimen-as administered in this study-should not be considered a standard treatment of perioperative chemotherapy for high-risk STS in the extremities and trunk. CLINICAL TRIAL REGISTRATION: jRCTs031180003.

Postoperative early and proactive grip strength training program for distal radius fractures promotes earlier recovery of grip strength: A retrospective study.

ABSTRACT: The use of volar locking plates (VLPs) for distal radius fractures has remarkably improved clinical outcomes; however, there are some reports of delayed recovery of grip strength. Since January 2019, we have been conducting an early and proactive grip strength training program (EGTP). In this program, 20 minutes of grip strength training-using a gripper with a load of 0.7 kg-was initiated from 2 weeks after surgery; the load was then gradually increased. From 6 weeks postsurgery, daily home grip strength training was performed using a gripper with a load of 5 kg, provided to the patient.We investigated whether the introduction of the EGTP could lead to earlier recovery of grip strength. We also examined whether the EGTP caused postoperative correction loss at the fractured site, or contributed to the early improvement of wrist function.Thirty-nine patients who underwent surgery using VLPs for distal radius fractures were included in this study; 20 followed the EGTP (EGTP group) and 19 patients did not (NGTP group). For these patients, grip strength and range of motion of the wrist joint were evaluated both 3 and 6 months postoperatively. The Quick Disabilities of the Arm, Shoulder, and Hand (qDASH) scores were also evaluated 6 months postoperatively. Additionally, corrective losses of radial inclination (RI), palmar tilt (PT), and ulnar variance (UV)-occurring from immediately postsurgery to 6 months after surgery-were evaluated.At both 3 and 6 months postoperatively, the grip strength of the EGTP group was significantly higher than that of the NGTP group. Regarding range of motion, only palmar flexion was significantly improved in the EGTP group at 3 months postoperatively. Conversely, no differences in corrective losses of RI, PT, and UV, or in qDASH scores, were observed between the two groups.The results of this study suggest that the EGTP can provide early recovery of grip strength and palmar flexion of the wrist without causing corrective loss at the fracture site.

Alleviation of hand-skin roughness after use of alcohol-based hand rub with inhibitory effects on Staphylococcus aureus-producing δ-toxin.

INTRODUCTION: Staphylococcus aureus colonizes rough regions of the skin of the hand. Healing of S. aureus-mediated wounds is promoted by the application of RNA III inhibiting peptide, which inhibits the production of S. aureus virulence factors, including δ-toxin. Herein, we investigated the level of hand-skin roughness in healthcare professionals after they used an alcohol-based hand rub containing polyoxyethylene lauryl ether (formulation E), which inhibits S. aureus δ-toxin production. METHODS: The inhibition rate of S. aureus δ-toxin production by hand rubs, including formulation E, was calculated by quantifying S. aureus δ-toxin concentration in culture medium using high-performance liquid chromatography. Healthcare professionals used formulations E or S (reference alcohol-based hand rub) for 4 weeks. The surface evaluation of the scaliness (SEsc) value was used as an indicator of hand skin roughness. The ΔSEsc value was calculated by subtracting the SEsc value before using the alcohol-based hand rub from the SEsc value 4 weeks after use. RESULTS: The inhibition rates of S. aureus δ-toxin production by formulations E and S were 43% and 10%, respectively. Formulation E significantly reduced ΔSEsc. The difference in ΔSEsc values after using formulations E and S was significant. CONCLUSIONS: The inhibitory effect on S. aureus δ-toxin production was higher with formulation E than with formulation S. Compared to formulations S, formulation E was effective at reducing scaliness and alleviating hand-skin roughness. Furthermore, the inhibitory effect of formulation E on S. aureus δ-toxin production could be associated with a reduction in scaliness and alleviation of hand-skin roughness.

Lasso loop technique using bioabsorbable thread to treat intra-articular distal radius fracture.

ABSTRACT: This article introduces our lasso loop technique (LLT) using a bioabsorbable thread for the treatment of intra-articular distal radius fractures with displaced dorsal bone fragment containing articular surface (DBF). We also examined whether the articular gap is sufficiently reduced and maintained by the LLT, along with the results of other radiological and clinical evaluations. We retrospectively reviewed 19 patients who underwent LLT for intra-articular distal radius fracture with a displaced DBF. Patient radiographic images and medical records were used to investigate radiological characteristics, symptoms, physical findings, and the Quick Disabilities of the Arm, Shoulder, and Hand scores. Sagittal-view computed tomography showed that the mean preoperative articular gap was 2.6 mm, but the gap was reduced by LLT, and the gap immediately postoperatively was <1.0 mm in all patients. No re-displacement of the DBF was evident from immediately postoperatively to 6 months postoperatively. Postoperatively, no losses of correction in palmar tilt, radial inclination, or ulnar variance were seen in the evaluation of plain radiographs, and satisfactory joint range of motion, grip strength, and the Quick Disabilities of the Arm, Shoulder, and Hand score were obtained. No significant complications due to LLT were observed. LLT appears to offer a simple and effective procedure to reduce displaced DBF with little risk of complications. LLT may become a useful option in the treatment of intra-articular distal radius fractures with displaced DBF.

Rapalink-1 and Hydroxychloroquine Exhibit an Additive Effect in Undifferentiated Pleomorphic Sarcoma by Inducing Apoptosis.

BACKGROUND/AIM: Advanced undifferentiated pleomorphic sarcoma (UPS) has a poor prognosis and there are few treatments that can improve overall survival. Recently, Rapalink-1, a third-generation mammalian target of rapamycin (mTOR) kinase inhibitor, has been developed and shown to be effective against other tumours. However, mTOR inhibitors have been shown to induce autophagy and resistance to anti-cancer drugs. This study aimed to investigate the antitumor effects of Rapalink-1 with an autophagy inhibitor. MATERIALS AND METHODS: The antitumor effect of Rapalink-1 and/or hydroxychloroquine in three UPS cell lines was examined via cell viability analysis, western blotting, flow cytometry and immunofluorescence. RESULTS: Rapalink-1 decreased cell proliferation and inhibited the PI3K/mTOR pathway. Combined treatment with Rapalink-1 and hydroxychloroquine enhanced the antitumor effect compared to treatment with Rapalink-1 alone by blocking the autophagy-inducing effect of mTOR inhibitors. CONCLUSION: Combined treatment with Rapalink-1 and hydroxychloroquine may be used as a potential therapeutic agent against UPS.

Preservation of Residual Limb Length with Antibiotic-loaded Bone Cement Implantation to Treat Femoral Periprosthetic Infection: A Case Report.

BACKGROUND: : Fitting a femoral prosthesis in a transfemoral amputee with a very short amputation stump is challenging. This case report aimed to introduce an effective and simple method that can preserve the residual limb length by the implantation of antibiotic-loaded bone cement for the treatment of a patient with femoral periprosthetic infection. CASE: : A 30-year-old man who had osteosarcoma at the age of 13 years underwent transfemoral amputation 17 years after the initial surgery because of periprosthetic infection. Antibiotic-loaded bone cement was inserted into the infected bone marrow to control the residual infection and to preserve the stump length. The infection resolved, and the patient regained functional gait using a femoral prosthesis. DISCUSSION: : This case report demonstrates the usefulness of antibiotic-loaded cement in preserving the length of residual limbs and for femoral prosthesis fitting after periprosthetic infection. Maintaining the residual bone length is crucial in amputees for the functional fitting of femoral prostheses. The use of antibiotic-loaded bone cement has potential as a simple and useful surgical option in amputees after periprosthetic infection.

Eccentric Rotational Acetabular Osteotomy Using Computed Navigation Guidance for Developmental Dysplasia of the Hip, Sacroiliac Fusion, and Femoroacetabular Impingement Owing to Acetabular Retroversion: A Case Report.

BACKGROUND: Developmental dysplasia of the hip (DDH) is the main factor that causes secondary osteoarthritis of the hip (hip OA). Acetabular retroversion results in pincer-type femoroacetabular impingement (FAI), and this is also known to cause secondary hip OA. However, few cases of DDH with acetabular retroversion have been reported, and there is no definite opinion on the optimal treatment. We report a rare case of DDH and FAI owing to acetabular retroversion and dysostosis of the sacroiliac joint that was treated with eccentric acetabular rotational osteotomy (ERAO) using navigation guidance. CASE PRESENTATION: A 27-year-old woman presented with DDH and acetabular retroversion with FAI and dysostosis of the sacroiliac joint on the contralateral side. We performed ERAO using computed navigation guidance and improved the coverage and retroversion of the acetabulum. The acetabular anteversion angle improved from 1° retroversion to 9° anteversion after surgery, the center edge angle improved from 18° to 43°, and the acetabular head index improved from 69% to 93%. The cam lesion of the femur was resected. The Harris Hip Score improved from 55.7 to 100 points at the final examination 2 years after surgery. CONCLUSIONS: In this rare case of DDH and FAI, ERAO using computed navigation guidance accurately improved the coverage and retroversion of the acetabulum.

Combined administration of rifampicin, ethambutol, and clarithromycin for the treatment of tenosynovitis of the hand caused by Mycobacterium avium complex: Case series and literature review.

ABSTRACT: We report the clinical results and problems of combined administration of rifampicin, ethambutol, and clarithromycin (REC) for the treatment of Mycobacterium avium complex (MAC) infection of the hand (hand MAC).Participants included 7 patients with hand MAC. After resection of the infected lesion, REC was prescribed for 12 months. For these patients, the site of infection, clinical course after initiation of REC, adverse drug effects (ADEs), and incidence of recurrence were evaluated.Sites of infection were the flexor tenosynovium in 5 patients, extensor tenosynovium in 1 patient, and both flexor and extensor tenosynovium in 1 patient. ADEs of REC occurred in 5 patients, and included visual disturbance caused by ethambutol in 2 patients, liver function abnormality caused by rifampicin in 2 patients, and fever with diarrhea caused by rifampicin in 1 patient. For 2 of these 5 patients, desensitization therapy was applied and REC was able to be reinstated. In the remaining 3 patients, the causative drugs were discontinued and levofloxacin, a new quinolone, was administered. Complete healing was achieved in 5 patients, and recurrence was observed in 2 patients. These 2 patients with recurrence included 1 patient in whom REC was completed and 1 patient in whom REC therapy was modified due to ADE.REC provided relatively good clinical results as a treatment for hand MAC. However, recurrences were observed even after the completion of REC and the use of an alternative drug. Optimal duration of REC and appropriate alternative drugs need to be identified in the future.

Carbon dioxide inhibits UVB-induced inflammatory response by activating the proton-sensing receptor, GPR65, in human keratinocytes.

Carbon dioxide (CO2) is the predominant gas molecule emitted during aerobic respiration. Although CO2 can improve blood circulation in the skin via its vasodilatory effects, its effects on skin inflammation remain unclear. The present study aimed to examine the anti-inflammatory effects of CO2 in human keratinocytes and skin. Keratinocytes were cultured under 15% CO2, irradiated with ultraviolet B (UVB), and their inflammatory cytokine production was analyzed. Using multiphoton laser microscopy, the effect of CO2 on pH was observed by loading a three-dimensional (3D)-cultured epidermis with a high-CO2 concentration formulation. Finally, the effect of CO2 on UVB-induced erythema was confirmed. CO2 suppressed the UVB-induced production of tumor necrosis factor-α (TNFα) and interleukin-6 (IL-6) in keratinocytes and the 3D epidermis. Correcting medium acidification with NaOH inhibited the CO2-induced suppression of TNFα and IL-6 expression in keratinocytes. Moreover, the knockdown of H+-sensing G protein-coupled receptor 65 inhibited the CO2-induced suppression of inflammatory cytokine expression and NF-κB activation and reduced CO2-induced cyclic adenosine monophosphate production. Furthermore, the high-CO2 concentration formulation suppressed UVB-induced erythema in human skin. Hence, CO2 suppresses skin inflammation and can be employed as a potential therapeutic agent in restoring skin immune homeostasis.

Bone Union Enhancement by bFGF-Containing HAp/Col in Prefabricated Vascularized Allo-Bone Grafts.

BACKGROUND: We have developed a prefabricated vascularized allo-bone graft (PVAG) by implanting the saphenous vascular bundles of recipient rats into transplanted donor bones in a flow-through manner. We previously demonstrated that the angiogenetic and bone formative abilities of the PVAG are stimulated by the addition of a basic fibroblast growth factor (bFGF)-containing hydroxyapatite/collagen (HAp/Col). This study aimed to demonstrate that the bone union ability of the PVAG is similarly stimulated by the bFGF-containing HAp/Col composite. METHODS: Sprague-Dawley donor rats (n = 32) and Wistar recipient rats (n = 32) were used in this study. The PVAG was fixed to the femur of the recipient rat using K-wire (dimeter: 0.7 mm) pinning, followed by suturing with a 4-0 nylon suture. Recipients were divided into four groups: with or without vascular bundles, and with or without bFGF-containing HAp/Col. Rats were sacrificed 6 weeks after transplantation, and bone union, bone resorption, and angiogenesis were radiologically and histologically evaluated. RESULTS: Radiological analysis revealed a significant increase in callus formation and union rate, while histological analysis showed a significant increase in bone formation and angiogenesis in the group treated with both vascular bundles and bFGF. Bone resorption did not significantly increase in any of the evaluated groups. CONCLUSION: Osteogenic cells, osteoconductive scaffolds, growth factors, and mechanical environment are known to be important factors in the process of fracture healing. The PVAG developed herein contains osteogenic cells, osteoconductive scaffolds, and growth factors. In addition, the PVAG is rigidly fixed to the fracture site, providing a stable mechanical environment. Together, these four factors contributed to a good bone union. Furthermore, this method did not promote bone resorption. Thus, the addition of a vascular bundle and bFGF-containing HAp/Col makes it possible to create an ideal vascularized allo-bone graft for the reconstruction of massive bone defects.

Effects of VEGF on Prefabricated Vascularized Bone Allografts in Rats.

BACKGROUND: Massive bone defects after wide resection of malignant bone tumors or a serious injury require treatment using vascularized bone grafts. Although cadaveric bone allografts combined with vascularized bone autografts are currently thought to be ideal in terms of size and durability, this treatment requires the scarification of healthy bone tissue. In a previous study, we attempted to improve this situation by prefabricating a vascularized bone allograft in recipient rats. In this study, we added vascular endothelial growth factor (VEGF)-containing hydroxyapatite/collagen composite (HAp/Col) to a prefabricated vascularized bone allograft to stimulate angiogenesis, which is known to be important for bone formation. METHODS: Sprague Dawley rats (n = 50) were used as donors and Wistar rats (n = 50) as recipients. All rats were 9 weeks old. The recipient rats were divided into five groups according to the use of vascular bundles, HAp/Col, and an additive substance (VEGF). The bone allografts collected from the donors were transplanted into the thigh region of the recipients, and a saphenous vein and 10 µg HAp/Col with VEGF were inserted into the bone allografts through the slit. After 4 weeks, the transplanted bone allografts were harvested, and histologic and genetic evaluations were performed in relation to bone formation and resorption. RESULTS: The results showed that, compared with the control group, the implantation of the vascular bundles and VEGF-containing HAp/Col significantly stimulated angiogenesis and bone formation in the rats with the bone allografts. However, histological and genetic evaluations of bone resorption revealed that resorption was not observed in any group. CONCLUSION: These results suggest that VEGF-containing HAp/Col effectively stimulates angiogenesis and bone formation, but not bone resorption, in prefabricated vascularized bone allografts. This method could therefore become a useful tool for treating large bone defects.

Prosthetic joint infection after total hip arthroplasty caused by Sneathia sanguinegens: A case report (CARE-complaint).

INTRODUCTION: Sneathia sanguinegens(S sanguinegens) is a gram-negative rod-shaped bacterium mostly reported to cause a perinatal infection, and there are no reports of S sanguinegens in prosthetic joint infection (PJI). The purpose of this report is to describe a very rare case of PJI after total hip arthroplasty (THA) caused by S sanguinegens. PATIENT CONCERNS: A 79-year-old woman presented with right coxalgia, inability to walk, and a fever of 39°C. She had undergone THA 28 years earlier for osteoarthritis of the hip. DIAGNOSES: The diagnosis was acute late-onset PJI, because blood tests revealed marked inflammatory reaction and computed tomography showed an abscess at the right hip joint; synovial fluid analysis resulted in detection of a gram-negative bacillus. INTERVENTION: Surgical debridement with retention of the implant and antibiotic therapy was performed. OUTCOMES: One month after surgery, polymerase chain reaction (PCR) assay showed that the pathogen was 99.9% likely to be S sanguinegens. There has been no recurrence of infection or loosening of the implant in the 2 years since her surgery. LESSONS: PCR should facilitate detection of previously unknown pathogens and potentially novel bacterial species.

Subcapital Fracture with Avascular Necrosis of the Whole Femoral Head After Fixation of an Intertrochanteric Fracture: A Case Report.

INTRODUCTION: Subcapital fractures following internal fixation of an intertrochanteric fracture are relatively rare. It has been reported that these fractures are caused by improper placement of implants, osteoporosis, and any trauma episode. We report a rare case of subcapsular fracture possibly caused by whole femoral head necrosis following intertrochanteric fracture treatment. CASE REPORT: An 88-year-old woman fell and sustained an intertrochanteric fracture of the left femur. She was treated with a short femoral nail (SFN) and 3 months after the surgery, bone union was observed. One year after the internal fixation of the intertrochanteric fracture, she complained of the left hip joint pain without any trauma, and the X-ray showed a subcapital fracture of the femur. She underwent nail removal and was treated with a bipolar hemiarthroplasty. Magnetic resonance imaging showed a change in the signal intensity of the entire head, and pathological findings revealed osteonecrosis. Normally, the reaction of bone resorption occurs below the necrosis area. We believe that the avascular necrosis (AVN) of the whole femoral head made the subcapital area fragile, resulting in a subcapital fracture. CONCLUSIONS: We should consider AVN of the whole femoral head as a potential cause of subcapital fracture after SFN fixation of intertrochanteric fractures.

Fracture of the Femoral Component Caused by Insufficient Crimping after Modern Unicompartmental Knee Arthroplasty.

Fracture of a femoral component after modern unicompartmental knee arthroplasty is very rare. Although this is not the first case on this subject, no study has reported insufficient crimping as the cause of femoral component loosening that led to breakage of a metallic component. A 69-year-old man underwent medial unicompartmental knee arthroplasty for right medial knee osteoarthritis. His early postoperative course was good; however, the 1-year postoperative radiograph showed an apparent radiolucent line around the femoral component, and he occasionally had right knee pain. However, he had been followed up conservatively because he had been doing well even while doing heavy agricultural work. At 8 years after surgery, because breakage of the femoral component was found, revision surgery was performed using bicruciate-retaining total knee arthroplasty. The removed fractured femoral component revealed a thick cement mantle detached from the bone surface. The postoperative course of the patient after the revision surgery was excellent. We suggest that the causes of femoral component breakage include early implant loosening caused by uneven cement crimping of the femoral component to the bone and excessive loading stress as a result of heavy labour.