Clinical and safety outcomes of simultaneous bilateral total knee arthroplasty for Japanese octogenarian patients: a retrospective analysis.

PURPOSE: The demand for simultaneous bilateral total knee arthroplasty (SiBTKA) in older adults is expected to increase with an aging population, thus necessitating evaluating its efficacy and safety. However, there is limited information regarding the clinical outcomes of SiBTKA in older adults, particularly in octogenarians. We aimed to assess the clinical outcomes and safety of SiBTKA in Japanese patients aged ≥ 80 years. METHODS: Of the 176 consecutive knees that underwent SiBTKA between July 2016 and January 2022 at our hospital, 172 were selected. They were divided into two groups according to the patient age as follows: the octogenarian group (≥ 80 years, 74 knees) and the younger control group (< 80 years, 98 knees). In addition, we assessed their preoperative clinical information, clinical outcomes using the Knee Society Score for knee (KSS-K) and function (KSS-F), and the incidence of early (≤ 90 days) and late (> 90 days) postoperative complications. RESULTS: The mean follow-up period was 3.5 years. The KSS-K scores of both groups improved postoperatively than that preoperatively. Both preoperative and postoperative KSS-F scores were lower in the octogenarians; however, their improvement rates were similar to those of the younger controls. We observed no significant intergroup differences in early or late postoperative complications, including infection, systemic complications, periprosthetic fractures, aseptic loosening, and mortality. CONCLUSION: SiBTKA for octogenarians had clinical outcomes and postoperative complication incidence similar to that for younger controls. Therefore, SiBTKA may be a safe and effective treatment option for octogenarians with painful bilateral knee deformities.

Preoperative incidence and risk factors of deep vein thrombosis in Japanese patients undergoing total hip arthroplasty.

PURPOSE: Preoperative deep vein thrombosis (DVT) is a risk factor for postoperative venous thromboembolism (VTE), causing severe mortality. Early detection of preoperative DVT is essential to prevent postoperative VTE. However, little is known regarding preoperative DVT in patients undergoing major surgery. The present study aimed to determine the incidence and risk factors of preoperative DVT in patients admitted for total hip arthroplasty (THA). METHODS: From August 2017 to September 2022, 243 patients admitted for THA at our institution were enrolled in this study. Patients medical records and preoperative laboratory data were retrospectively collected. According to the results of lower-limb ultrasonography, patients were divided into either the non-DVT (n = 136) or DVT (n = 43) group. The incidence of DVT and independent risk factors for preoperative DVT were investigated using univariate and multivariate logistic regression analyses. RESULTS: The mean age was 74.0 ± 8.4 years. Preoperative DVT was diagnosed in 43 of the 243 (17.7%) patients. The risk of DVT was significantly high (p < 0.05) in patients with advanced age, increased D-dimer levels, and malnutrition status, as assessed by the Geriatric Nutritional Risk Index (GNRI). Multivariate analysis showed that advanced age, increased D-dimer level, and malnutrition status assessed by the GNRI were independent risk factors for preoperative DVT. CONCLUSION: A high incidence of preoperative DVT was observed in patients undergoing THA. Advanced age, increased D-dimer levels, and malnutrition assessed by the GNRI increased the risk of preoperative DVT. Screening high-risk subgroups for preoperative DVT is necessary to prevent postoperative VTE.

Clinical and radiological outcomes of total hip arthroplasty in octogenarian patients using a three-dimensional porous titanium cup: a retrospective analysis in Japanese patients.

PURPOSE: Osteointegration of a three-dimensional (3D) porous titanium material has been experimentally proven, but only a few studies have shown the clinical outcomes of a 3D porous titanium cup in the Japanese elderly population. The purpose of this study was to compare the short-and-medium term clinical and radiographic results of total hip arthroplasty (THA) using a 3D porous titanium cup in patients aged ≥ 80 (octogenarians) versus those aged < 80 (younger controls). METHODS: A total of 104 hips that underwent THA using a 3D porous titanium cup (SQRUM TT, Kyocera Medical) were enrolled in the study and were divided into two groups according to age: the octogenarian group (≥ 80, n = 42) and the younger control group (< 80, n = 62). Furthermore, we evaluated patient characteristics, clinical outcomes determined by the Japanese Orthopedic Association score, cup alignment, and incidence of radiolucent lines around the cup. RESULTS: The mean follow-up period was 4.2 and 4.0 years (p = 0.29) for octogenarians and younger controls, respectively. The clinical outcomes were excellent, and no revision surgery occurred until the last follow-up in both groups. The number of patients with radiolucent lines at the final evaluation was 21 of 62 (33.9%) in younger controls and 16 of 42 (38.1%) in octogenarians. CONCLUSION: THA with 3D porous titanium cup for octogenarians had similar clinical outcomes and incidence of radiolucent lines as those of younger controls, suggesting that the 3D porous titanium cup may be useful in THA for octogenarians. Further investigations will confirm its long-term outcomes.

Effect of Antimicrobial Prophylaxis Duration on Health Care-Associated Infections After Clean Orthopedic Surgery: A Cluster Randomized Trial.

Importance: Postoperative health care-associated infections are associated with a greater deterioration in patients' general health status and social and economic burden, with at least 1 occurring in approximately 4% of acute care hospital patients. Antimicrobial prophylaxis prevents surgical site infections in various orthopedic procedures; however, its relationship with health care-associated infections remains unknown. Objective: To examine whether a shorter antimicrobial prophylaxis duration of less than 24 hours after surgery is not inferior to a longer duration in preventing health care-associated infections after clean orthopedic surgery. Design, Setting, and Participants: This open-label, multicenter, cluster randomized, noninferiority clinical trial was conducted in 5 tertiary referral hospitals in greater Tokyo metropolitan area, Japan, from May to December 2018. Adult patients undergoing clean orthopedic surgery were recruited until the planned number of participants was achieved (500 participants per group). Statistical analysis was conducted from July to December 2019. Interventions: Antimicrobial prophylaxis was discontinued within 24 hours after surgery in group 24 and 24 to 48 hours after surgery in group 48. Group allocation was switched every 2 or 4 months according to the facility-based cluster rule. Study-group assignments were masked from participants. Main Outcomes and Measures: The primary outcome was the incidence of health care-associated infections requiring antibiotic therapies within 30 days after surgery. The noninferiority margin was 4%. Results: Of the 1211 participants who underwent cluster allocation, 633 participants were in group 24 (median [IQR] age, 73 [61-80] years; 250 men [39.5%] and 383 women [60.5%]), 578 participants were in group 48 (median [IQR] age, 74 [62-81] years; 204 men [35.3%] and 374 women [64.7%]), and all were eligible for the intention-to-treat analyses. Health care-associated infections occurred in 29 patients (4.6%) in group 24 and 38 patients (6.6%) in group 48. Intention-to-treat analyses showed a risk difference of -1.99 percentage points (95% CI, -5.05 to 1.06 percentage points; P < .001 for noninferiority) between groups, indicating noninferiority. Results of adjusted intention-to-treat, per-protocol, and per designated procedure population analyses supported this result, without a risk of antibiotic resistance and prolonged hospitalization. Conclusions and Relevance: This cluster randomized trial found noninferiority of a shorter antimicrobial prophylaxis duration in preventing health care-associated infections without an increase in antibiotic resistance risk. These findings lend support to the global movement against antimicrobial resistance and provide additional information on adequate antimicrobial prophylaxis for clean orthopedic surgery. Trial Registration: Identifier: UMIN000030929.

Effects of knee extension exercise starting within 4 h after total knee arthroplasty.

PURPOSE: To determine the beneficial effects of knee extension exercise applied from 4 h after TKA. METHODS: Patients undergoing TKA for osteoarthritis were assigned to early rehabilitation (n = 41) and control rehabilitation (n = 39) groups. Rehabilitation of knee extension exercise was started within 4 h postoperative in the early group and 2 days after surgery in the control group. Joint range of motion and pain were assessed before surgery and at 3 days to 12 months after surgery. Muscle strength and gait parameters were assessed before and 3 weeks after surgery. RESULTS: Extension range of motion was significantly increased in the early group than the control at 3 days, 3 weeks and 6 months after surgery. In gait parameters, peak knee flexion and extension angles during stance phase were significantly improved in the early group than the control group at 3 weeks after surgery. Flexion range of motion was increased in the early group than the control at 12 months after surgery. CONCLUSION: Starting knee extension exercise within 4 h after TKA reduced the early loss of extension range of motion and improved gait pattern and seemed to contribute to be better functional outcome one year after surgery.

Intraosseous epidermal cyst of the great toe that was difficult to distinguish from chronic osteomyelitis: A case report and literature review.

Obtaining a correct intraosseous epidermal cyst diagnosis is difficult due to the extreme rarity of this cyst. Further, the clinical manifestations and radiographic findings are very similar to those of a malignancy or infection. Early histopathological analysis is required for accurate diagnosis and for avoiding unnecessary antibiotic administration and amputation.

Optimization of a Bayesian penalized likelihood algorithm (Q.Clear) for 18F-NaF bone PET/CT images acquired over shorter durations using a custom-designed phantom.

BACKGROUND: The Bayesian penalized likelihood (BPL) algorithm Q.Clear (GE Healthcare) allows fully convergent iterative reconstruction that results in better image quality and quantitative accuracy, while limiting image noise. The present study aimed to optimize BPL reconstruction parameters for 18F-NaF PET/CT images and to determine the feasibility of 18F-NaF PET/CT image acquisition over shorter durations in clinical practice. METHODS: A custom-designed thoracic spine phantom consisting of several inserts, soft tissue, normal spine, and metastatic bone tumor, was scanned using a Discovery MI PET/CT scanner (GE Healthcare). The phantom allows optional adjustment of activity distribution, tumor size, and attenuation. We reconstructed PET images using OSEM + PSF + TOF (2 iterations, 17 subsets, and a 4-mm Gaussian filter), BPL + TOF (ß = 200 to 700), and scan durations of 30-120 s. Signal-to-noise ratios (SNR), contrast, and coefficients of variance (CV) as image quality indicators were calculated, whereas the quantitative measures were recovery coefficients (RC) and RC linearity over a range of activity. We retrospectively analyzed images from five persons without bone metastases (male, n = 1; female, n = 4), then standardized uptake values (SUV), CV, and SNR at the 4th, 5th, and 6th thoracic vertebra were calculated in BPL + TOF (ß = 400) images. RESULTS: The optimal reconstruction parameter of the BPL was ß = 400 when images were acquired at 120 s/bed. At 90 s/bed, the BPL with a ß value of 400 yielded 24% and 18% higher SNR and contrast, respectively, than OSEM (2 iterations; 120 s acquisitions). The BPL was superior to OSEM in terms of RC and the RC linearity over a range of activity, regardless of scan duration. The SUVmax were lower in BPL, than in OSEM. The CV and vertebral SNR in BPL were superior to those in OSEM. CONCLUSIONS: The optimal reconstruction parameters of 18F-NaF PET/CT images acquired over different durations were determined. The BPL can reduce PET acquisition to 90 s/bed in 18F-NaF PET/CT imaging. Our results suggest that BPL (ß = 400) on SiPM-based TOF PET/CT scanner maintained high image quality and quantitative accuracy even for shorter acquisition durations.

Blue moon ensemble simulation of aquation free energy profiles applied to mono and bifunctional platinum anticancer drugs.

Aquation free energy profiles of neutral cisplatin and cationic monofunctional derivatives, including triaminochloroplatinum(II) and cis-diammine(pyridine)chloroplatinum(II), were computed using state of the art thermodynamic integration, for which temperature and solvent were accounted for explicitly using density functional theory-based canonical molecular dynamics (DFT-MD). For all the systems, the "inverse-hydration" where the metal center acts as an acceptor of hydrogen bond has been observed. This has motivated to consider the inversely bonded solvent molecule in the definition of the reaction coordinate required to initiate the constrained DFT-MD trajectories. We found that there exists little difference in free enthalpies of activation, such that these platinum-based anticancer drugs are likely to behave the same way in aqueous media. Detailed analysis of the microsolvation structure of the square-planar complexes, along with the key steps of the aquation mechanism, is discussed.

Non-inferior comparative study comparing one or two day antimicrobial prophylaxis after clean orthopaedic surgery (NOCOTA study): a study protocol for a cluster pseudo-randomized controlled trial comparing duration of antibiotic prophylaxis.

BACKGROUND: Antimicrobial prophylaxis (AMP) is one of the most important measures for preventing surgical site infections (SSIs); however, controversies remain regarding its adequate duration. Although the World Health Organization and the Center for Disease Control and Prevention do not recommend additional AMP after closure, the American Society of Health-System Pharmacists and the Musculoskeletal Infection Society permit the use of postoperative AMP, but recommend discontinuation within 24 h. Similarly, the Japanese Society of Chemotherapy and the Japan Society for Surgical Infection also permit AMP within 24-48 h after various orthopaedic procedures. In these guidelines, recommendations regarding AMP duration were weak due to a relative lack of evidence, and currently, there is no high-quality evidence comparing AMP use within 24 h versus 24-48 h regarding orthopaedic procedures. Urinary tract infection (UTI) and respiratory tract infection (RTI) are also important health care-associated infections (HAIs) faced after surgery. Although AMP duration may affect these HAIs, its effects have not been well evaluated. METHODS: We have organized a multicenter, prospective, cluster pseudo-randomized controlled trial to examine the non-inferiority of shorter AMP duration (within 24 h) against longer duration (24-48 h) in preventing postoperative HAIs. Participating facilities will be divided into two groups. In Group 24, AMP will be discontinued within 24 h after surgery. In Group 48, AMP will be discontinued within 24-48 h after surgery. The group allocation will be switched every 2 months until the targeted recruitment (500 participants per group) is met. The primary outcome will be the cumulative incidence of all HAIs (SSI, UTI, RTI, and other infectious diseases), which require antibiotic therapies within 30 days after surgery. In addition to mortality and cardiovascular events, prolonged hospitalization (> 30 days) and the rate of antibiotic resistance rate of SSI pathogens will also be evaluated. Outcomes will be evaluated within 30-180 days after surgery in person by the surgeon, by mail, or by telephone survey. Data will be analyzed by a statistician not engaged in data collection. DISCUSSION: This study may provide valuable information for developing future recommendations for adequate AMP duration after clean orthopaedic surgery. TRIAL REGISTRATION: UMIN000030929, registered January 22, 2018.

Intraarticular injection of processed lipoaspirate cells has anti-inflammatory and analgesic effects but does not improve degenerative changes in murine monoiodoacetate-induced osteoarthritis.

BACKGROUND: Previous basic research and clinical studies examined the effects of mesenchymal stem cells (MSCs) on regeneration and maintenance of articular cartilage. However, our pilot study suggested that MSCs are more effective at suppressing inflammation and pain rather than promoting cartilage regeneration in osteoarthritis. Adipose tissue is considered a useful source of MSCs; it can be harvested easily in larger quantities compared with the bone marrow. The present study was designed to evaluate the anti-inflammatory, analgesic, and regenerative effects of intra-articularly injected processed lipoaspirate (PLA) cells (containing adipose-derived MSCs) on degenerative cartilage in a rat osteoarthritis model. METHODS: PLA cells were isolated from subcutaneous adipose tissue of 12-week-old female Sprague-Dawley rats. Osteoarthritis was induced by injection of monoiodoacetate (MIA). Each rat received 1 × 106 MSCs into the joint at day 7 (early injection group) and day 14 (late injection group) post-MIA injection. At 7, 14, 21 days after MIA administration, pain was assessed by immunostaining and western blotting of dorsal root ganglion (DRG). Cartilage quality was assessed macroscopically and by safranin-O and H&E staining, and joint inflammation was assessed by western blotting of the synovium. RESULTS: The early injection group showed less cartilage degradation, whereas the late injection group showed cartilage damage similar to untreated OA group. The relative expression level of CGRP protein in DRG neurons was significantly lower in the two treatment groups, compared with the untreated group. CONCLUSIONS: Intra-articular injection of PLA cells prevented degenerative changes in the early injection group, but had little effect in promoting cartilage repair in the late injection group. Interestingly, intra-articular injection of PLA cells resulted in suppression of inflammation and pain in both OA groups. Further studies are needed to determine the long-term effects of intra-articular injection of PLA cells in osteoarthritis.

CD271-selected mesenchymal stem cells from adipose tissue enhance cartilage repair and are less angiogenic than plastic adherent mesenchymal stem cells.

CD271 is a marker of bone marrow MSCs with enhanced differentiation capacity for bone or cartilage repair. However, the nature of CD271+ MSCs from adipose tissue (AT) is less well understood. Here, we investigated the differentiation, wound healing and angiogenic capacity of plastic adherent MSCs (PA MSCs) versus CD271+ MSCs from AT. There was no difference in the extent to which PA MSCs and CD271+ MSCs formed osteoblasts, adipocytes or chondrocytes in vitro. In contrast, CD271+ MSCs transplanted into athymic rats significantly enhanced osteochondral wound healing with reduced vascularisation in the repair tissue compared to PA MSCs and control animals; there was little histological evidence of mature articular cartilage formation in all animals. Conditioned medium from CD271+ MSC cultures was less angiogenic than PA MSC conditioned medium, and had little effect on endothelial cell migration or endothelial tubule formation in vitro. The low angiogenic activity of CD271+ MSCs and improved early stage tissue repair of osteochondral lesions when transplanted, along with a comparable differentiation capacity along mesenchymal lineages when induced, suggests that these selected cells are a better candidate than PA MSCs for the repair of cartilaginous tissue.

Functional outcome of patients with unstable pelvic ring fracture.

The purpose of this study was to evaluate factors that correlated with unsatisfactory short- and long-term outcome in patients who sustained unstable pelvic ring fracture. The study subjects of this study were those of type B and C pelvic ring fractures (82 patients; mean age 54 years). Age, gender, associated injuries, fracture type, Injury Severity Score rating and treatment methods were assessed, and Majeed score for functional outcome and radiographic studies at 1 year after injury (short-term) and at final follow-up (long-term), with mean follow-up of 98 months were analyzed. Significant univariate factors ( p < 0.05) were entered in a multivariate logistic regression model to determine the independent predictors of unsatisfactory functional outcome. Univariate analysis showed that fractures of the lower extremity, nerve damage, conservative treatment, and radiological outcome correlated with unsatisfactory short-term functional outcome, while female gender, brain injury, nerve damage, conservative treatment, fracture location at the posterior portion of pelvic ring, radiological outcome, and pure sacroiliac dislocation only for type C fracture correlated with unsatisfactory long-term outcome. Multiple logistic regression analysis identified fractures of the lower extremity (odds ratio (OR): 5.364), conservative treatment (OR: 13.690), and nerve damage (OR: 21.392) as determinants of unsatisfactory short-term functional outcome and nerve damage (OR: 66.926) and poor radiological results (OR: 33.944) as determinant of long-term functional outcome. In patients with unstable pelvic ring injury, fractures of the lower extremity, conservative therapy, and nerve damage influenced short-term functional outcome, while that nerve damage and the pelvic ring displacement over 20 mm negatively affected long-term outcome.

Long-term clinical outcome of acetabular cup revision surgery: comparison of cemented cups, cementless cups, and cemented cups with reinforcement devices.

The aim of the present study was to analyze the clinical and radiographic outcomes and Kaplan-Meier survivorship of patients who underwent revision surgeries of the acetabular cup that had sustained aseptic loosening. We reviewed 101 consecutive patients (120 hips; 10 men 11 hips; 91 women 109 hips; age at surgery 66 years; range 45-85) who underwent acetabular component revision surgery, at a follow-up period of 15.6 years (range 10-32). To evaluate the state of the acetabulum, acetabular bony defects were classified according to the AAOS classification based on intraoperative findings: type I (segmental deficiencies n = 24 hips), type II (cavity deficiency n = 48), type III (combined deficiency n = 46), and type IV (pelvic discontinuity n = 2). The Harris hip score improved from 42.5 ± 10.8 (mean ± SD) before surgery to 74.9 ± 14.6 points at follow-up. The survival rates of the acetabular revision surgery with cemented, cementless, and cemented cups plus reinforcement devices were 74, 66, and 82 %, respectively. The difference in the survival rate between the cemented and cementless group was marginal (p = 0.048 Gehan-Breslow-Wilcoxon, p = 0.061 log-rank), probably due to the early-stage failure cases in the cementless group. The cementless and reinforcement groups included nine early-stage failure cases. To prevent early-stage failure, we recommend the cementless cups for types I and II acetabular bone defects with adequate contact between host bone and acetabular component, and the cemented cup with or without reinforcement devices, together with restoration of bone stock by impaction or structured bone grafting, for cases lacking such contact.

Extensive Loss of Tibialis Anterior Tendon: Surgical Repair With Split Tendon Transfer of Tibialis Posterior Tendon: A Case Report.

Extensive damage of the tibialis anterior tendon is rare and mainly caused by trauma. Surgical treatment of these injuries can become challenging owing to the limited availability of autogenous graft resources for reconstruction of the defect. In the present case report, we describe a large defect in the midfoot soft tissue after a traffic injury, which included complete loss of the tibialis anterior tendon. The tendon was reconstructed by split tendon transfer of the tibialis posterior tendon without sacrificing function, which was confirmed by the follow-up examination at 6 years after injury. We believe split tendon transfer of the tibialis posterior tendon can be one of the treatment options for patients with extensive disruption of the tibialis anterior tendon.

Anti-inflammatory and protective effects of 2-methacryloyloxyethyl phosphorylcholine polymer on oral epithelial cells.

Periodontitis is a chronic inflammatory disease initiated by a microbial biofilm formed in the periodontal pocket. Gingival epithelium plays important roles as the first physical barrier to bacterial invasion and in orchestrating the innate immune reaction via toll-like receptors (TLRs), which recognize various bacterial products, and maintaining its function. Newly developed oral care products to inhibit bacterial adherence, subsequent inflammatory reaction and protect the gingival epithelium are expected. We previously reported that 2-methacryloyloxyethyl phosphorylcholine (MPC)-polymer coating decreased bacterial adhesion to human oral keratinocytes, RT-7, and mouth-rinsing with MPC-polymer inhibited the increase of oral bacteria. In this study, regarding the possibility of MPC-polymer application for preventing the adherence of periodontal pathogen, subsequent inflammatory reaction and protection of gingival epithelium, we examined the effects of MPC-polymer on the adherence of Porphyromonas gingivalis, major periodontitis-related pathogen, and TLR2 ligand to RT-7 and subsequent interleukin (IL)-8 production. MPC-polymer treatment significantly reduced P. gingivalis adherence by 44% and TLR2-mediated IL-8 production by blocking the binding of its specific-ligand in a concentration-dependent manner. Furthermore, MPC-polymer pretreatment protected RT-7 from injury by chemical irritants, cetylpyridinium chloride. These findings suggest that MPC-polymer is potentially useful for oral care to prevent oral infection and to maintain oral epithelial function.

Anti-apoptotic Bcl-2 family member Mcl-1 regulates cell viability and bone-resorbing activity of osteoclasts.

Myeloid cell leukemia sequence 1 (Mcl-1) is an anti-apoptotic Bcl-2 family protein and an immediate early gene expressed during myeloid leukemia cell line differentiation. We analyzed the expression and function of Mcl-1 in osteoclasts. Mcl-1 protein exhibited a short half-life in osteoclasts caused by its degradation in the ubiquitin-proteasome system. Mcl-1 had no effect on osteoclast differentiation, but its overexpression prolonged osteoclast survival and suppressed the bone-resorbing activity of these cells, as determined by pit formation assay. Conversely, Mcl-1 depletion suppressed osteoclast survival and increased bone resorption. This negative role for Mcl-1 on the bone-resorptive activities of osteoclasts may be caused by the increase in adenosine triphosphate/adenosine diphosphate ratio. Finally, we showed that the local deletion of Mcl-1 by the injection of the Cre adenovirus into the calvaria of Mcl1(fl/fl) mice significantly affected GST-RANKL-induced bone resorption in vivo. These results demonstrated that Mcl-1 positively regulates cell viability and negatively regulates the bone-resorbing activity of osteoclasts both in vitro and in vivo.

[Role of mitochondria in osteoclast function].

Mitochondria, membrane-enclosed structures found in most eukaryotic cells, generate most of the cell's supply of ATP, used as a source of chemical energy. In addition to supplying cellular energy, mitochondria are involved in signaling, cellular differentiation, cell death, and the aging process. Osteoclasts, highly differentiated bone-resorbing cells of hematopoietic origin, have two conflicting tendencies : a lower capacity to survive and a higher capacity to execute energy-consuming activities such as bone resorption. We here highlight the role of mitochondria in osteoclast function. Recent studies have revealed that ATP depletion following Tfam (mitochondrial transcription factor A) deficiency leads to increased bone-resorbing activity despite accelerated apoptosis, and the release of endogenous ATP negatively regulates osteoclast function through an autocrine/paracrine feedback loop. These findings provide evidence for a previously unknown mechanism by which mitochondria regulate the inverse correlation between osteoclast survival and bone resorption.

Diaphyseal tibiofibular synostosis in a runner.

Diaphyseal tibiofibular synostosis is a very rare cause of shin and ankle pain. A 35-year-old male presented with complaints of left shin and ankle pain of 3 years duration that was sometimes worse after running a few miles. One year before presenting to our hospital, the actual cause for his pain was missed when only lumbar radiographs were taken at another institution. A full-length tibia film revealed a diaphyseal tibiofibular synostosis at our hospital. The presence of a synostosis should alert the surgeon to search for the various abnormalities usually associated with this condition. Magnetic resonance imaging and enhanced 3-dimensional computed tomography are essential to rule out the possibility of a neoplastic process and to determine its relation to the neurovascular structures. Simple excision of the synostosis can provide excellent symptomatic relief with a minimal risk of complications.

(18)F-FDG PET/CT for Diagnosis of Osteosclerotic and Osteolytic Vertebral Metastatic Lesions: Comparison with Bone Scintigraphy.

STUDY DESIGN: A retrospective study. PURPOSE: The aims of this study were to investigate the diagnostic value of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in PET/computed tomography (CT) in the evaluation of spinal metastatic lesions. OVERVIEW OF LITERATURE: Recent studies described limitations regarding how many lesions with abnormal (18)F-FDG PET findings in the bone show corresponding morphologic abnormalities. METHODS: The subjects for this retrospective study were 227 patients with primary malignant tumors, who were suspected of having spinal metastases. They underwent combined whole-body (18)F-FDG PET/CT scanning for evaluation of known neoplasms in the whole spine. (99m)Tc-methylene diphosphonate bone scan was performed within 2 weeks following PET/CT examinations. The final diagnosis of spinal metastasis was established by histopathological examination regarding bone biopsy or magnetic resonance imaging (MRI) findings, and follow-up MRI, CT and (18)F-FDG PET for extensively wide lesions with subsequent progression. RESULTS: From a total of 504 spinal lesions in 227 patients, 224 lesions showed discordant image findings. For 122 metastatic lesions with confirmed diagnosis, the sensitivity/specificity of bone scan and FDG PET were 84%/21% and 89%/76%, respectively. In 102 true-positive metastatic lesions, the bone scan depicted predominantly osteosclerotic changes in 36% and osteolytic changes in 19%. In 109 true-positive lesions of FDG PET, osteolytic changes were depicted predominantly in 38% while osteosclerotic changes were portrayed in 15%. CONCLUSIONS: (18)F-FDG PET in PET/CT could be used as a substitute for bone scan in the evaluation of spinal metastasis, especially for patients with spinal osteolytic lesions on CT.