Validation of a diagnostic flowchart for tuberculous pleurisy in pleural fluid with high levels of adenosine deaminase.

INTRODUCTION: Adenosine deaminase (ADA) in pleural fluid is a useful marker for diagnosing tuberculous pleurisy. However, recent studies have reported a lower specificity of pleural fluid ADA levels. We previously developed a diagnostic flowchart for patients with pleural fluid ADA ≥40 U/L, incorporating variables such as pleural fluid lactate dehydrogenase <825 U/L, predominant pleural fluid neutrophils or cell degeneration, and a pleural fluid ADA/total protein ratio <14. This flowchart was effective in distinguishing between tuberculous pleurisy and other diseases. Here, we conducted a validation analysis of this flowchart. MATERIALS AND METHODS: We retrospectively collected data from 458 patients with pleural fluid ADA concentrations ≥40 U/L across eight institutions from January 2019 to December 2023. The diagnostic accuracy rate, sensitivity, and specificity of the diagnostic flowchart were analysed and compared to those in the original study. RESULTS: Eighty-seven patients were diagnosed with tuberculous pleurisy, and 371 patients were diagnosed with other diseases. The diagnostic accuracy, sensitivity, and specificity for diagnosing tuberculous pleurisy were 77.7%, 86.2%, and 75.7%, respectively. Compared with that in the original study, the rate of tuberculous pleurisy was lower (19.0% vs. 44.5%, p < 0.001), but the diagnostic accuracy rates were not significantly different (p = 0.253). On the basis of the findings from this validation study, we have revised the flowchart to enhance its utility. CONCLUSION: The diagnostic flowchart exhibited high diagnostic accuracy in this validation study, comparable to that in the original study. This validation confirms the effectiveness of the flowchart, even in settings with a low incidence of tuberculosis.

Associations between birth weight and lung function in a Japanese adult population: The tohoku medical megabank community-based cohort study.

BACKGROUND: Birth weight, as a measure of intrauterine growth, is commonly used in epidemiological studies and is reported to be associated with adult lung function. However, findings regarding this association in previous studies have been inconsistent. Furthermore, no studies have reported associations stratified by age or smoking status, or adjusted for eosinophil count or other parameters related to type 2 airway inflammation. METHODS: This cross-sectional study included 2632 men and 7237 women aged ≥20 years living in Miyagi Prefecture, Japan. Lung function was assessed based on spirometry. Birth weight data were obtained through a questionnaire survey. Analysis of covariance was used to evaluate the associations between birth weight and lung function, adjusting for potential confounders. Stratified analyses by age and smoking status were also conducted, together with a sub-analysis for low birth-weight participants. RESULTS: Birth weight was positively associated with forced expiratory volume in 1 s (FEV1) for both sexes and with vital capacity in women, after adjusting for height, age, smoking status, and parameters related to type 2 airway inflammation. The stratified analysis for smoking status revealed associations in never-smokers and ex-smokers. When stratified by age, the associations were confirmed in middle-aged participants. The effect of smoking status on the FEV1 of low birth-weight participants was not significant. CONCLUSIONS: Our analysis of a large, Japanese adult population showed that birth weight was independently and positively associated with adult lung function, even after adjustment for age, height, smoking status, and parameters related to type 2 airway inflammation.

Involvement of orthopaedic surgeons for cancer patients in orthopaedic training facilities certified by the Japanese Orthopaedic Association - A nationwide survey.

BACKGROUND: In order to improve cancer care in Japan further, it is now required for orthopaedic surgeons to get actively involved in managing locomotive organs such as bones, muscles and nerves in cancer patients. In 2018, the Japanese Orthopaedic Association (JOA) conducted a questionnaire survey to investigate the current status of cancer treatment at the orthopaedic training facilities certified by the JOA. We analyzed the results of that questionnaire survey, focusing on the data from the core hospitals for cancer care (designated cancer hospitals), to clarify the involvement of orthopaedic surgeons in cancer treatment. MATERIALS AND METHODS: A nationwide survey was conducted in the orthopaedic training facilities certified by the JOA using an online questionnaire from March 15th to 31st, 2018. To clarify the involvement of orthopaedic surgeons in cancer treatment, we analyzed the results of that questionnaire survey, focusing on the data from the designated cancer hospitals in Japan. RESULTS: From the questionnaire survey, it became clear that 24% of the orthopaedic training facilities certified by the JOA are designated cancer hospitals. There were significant differences concerning cancer treatment and the prospect of orthopaedic surgeons' involvement in the treatment for bone metastases between institutions classified according to number of both certified orthopaedic surgeons by the JOA and specialists for bone and soft tissue tumors. In addition, in 45% of the designated cancer hospitals, orthopaedic surgeons treated bone metastases that occur in cancer patients, but in the rest of the institutions, orthopaedic surgeons did not yet adequately respond. CONCLUSION: In order to further improve the locomotive function and quality of life (QOL) in cancer patients, it was seemed to be necessary that all medical professionals engaged in cancer treatment, including orthopaedic surgeons, recognize the importance of locomotive management for cancer patients. In addition, the results of this study suggested that the presence of more than six certified orthopaedic surgeons by the JOA, including one or more specialists for bone and soft tissue tumors, may be able to create an environment conducive to the involvement of orthopaedic surgeons in cancer treatment at the facility.

Limitations of minimally invasive posterior cervical foraminotomy-a decompression method of posteriorly shifting the nerve root-in cases of large anterior osteophytes in cervical radiculopathy: A retrospective multicenter cohort study.

BACKGROUND: Posterior cervical foraminotomy against anterior osteophyte is an indirect decompression procedure but less invasive compared to anterior cervical discectomy and fusion. Residual compression to the nerve root may lead to poor surgical outcomes. Although clinical results of posterior cervical foraminotomy for osteophytes are not considered better than those of disk herniation, osteophyte size and the association of the decompression area with poor surgical outcomes remain unclear. This study aimed to identify the limitations of minimally invasive posterior cervical foraminotomy for cervical radiculopathy and discuss the methods to improve surgical outcomes. METHODS: We analyzed 55 consecutive patients with degenerative cervical radiculopathy who underwent minimally invasive posterior cervical foraminotomy. Minimum postoperative follow-up duration was 1 year. We divided the patients into nonimproved and improved groups. The cutoff value between preoperative and postoperative Neck Disability Index scores was 30% improvement. Preoperative imaging data comprised disk height, local kyphosis, spinal cord compression, anterior osteophytes in the foramen, and anterior osteophytes of >50% of the intervertebral foramen diameter. Postoperative imaging data comprised craniocaudal length and lateral width of decompressed lamina, preserved superior facet width, and area of decompressed lamina. RESULTS: Fifty-five patients were divided into two groups: nonimproved (n = 19) and improved (n = 36). The presence of osteophytes itself was not significant; however, the presence of osteophytes of >50% of the foramen diameter increased in the nonimproved group (P = 0.004). Mean lateral width and mean area of decompressed lamina after surgery significantly increased in the improved group (P = 0.001, P = 0.03). CONCLUSION: The presence of anterior osteophytes >50% of the diameter of the foramen led to poor improvement of clinical outcomes in minimally invasive posterior cervical foraminotomy. However, the larger the lateral width and area of the decompressed lamina, the better the surgical outcome.

Practical guidance to handle missing values in the 25-question Geriatric Locomotive Function Scale (GLFS-25): a simulation study.

OBJECTIVES: Despite the possible large number of missing values on the 25-question Geriatric Locomotive Function Scale (GLFS-25), how we should treat them is unknown. In a simulation study, we investigated how to handle missing values in the GLFS-25. DESIGN, SETTING AND PARTICIPANTS: We used three datasets with different participant characteristics: community dwellers who could walk by themselves, outpatients of orthopaedics owing to pain, and patients who required surgery for total knee replacement or lumbar spinal canal stenosis. OUTCOME MEASURES: The missing items of the datasets were artificially created, and four statistical methods, complete case analysis, multiple imputation, single imputation using individual mean, and single imputation using individual domain average, were compared in terms of bias and mean squared error. Simulation studies were conducted to compare them under varying numbers of participants with missing values (5%-40%) and under varying numbers of missing items of GLFS-25 (4-16). RESULTS: Multiple imputation had the lowest root mean squared error. Complete case analysis showed the largest bias, and the performances of the single imputation were between those methods. The relative performances were similar across the three datasets. The absolute bias of the single imputation was<0.1. The bias and mean squared error of multiple imputation and single imputation were comparable when the number of missing items was less than or equal to eight. CONCLUSIONS: Multiple imputation is preferable, although single imputation using subject average/subject domain average can be used with practically negligible bias as long as the number of missing items is up to 8 out of 25 items in each individual of the population.

Risk factors for residual pain after ligament reconstruction and tendon interposition on osteoarthritis of the first carpometacarpal joint.

BACKGROUND: Ligament reconstruction and tendon interposition (LRTI) is currently the most performed procedure for osteoarthritis (OA) of the thumb carpometacarpal (CMC) joint. In general, satisfactory outcomes are expected, although some patients complain of residual pain after LRTI. The objective of this study is to determine the factors associated with residual pain. METHOD: All patients with OA of the thumb CMC joint who underwent LRTI at our hospital between October 2013 and October 2018 and were regularly observed for at least 1 year were included. The following variables were extracted and included in the univariate analysis: sex, age, dominant hand, pain visual analog scale (VAS) score, Eaton classification, grip strength, pulp pinch strength, and metacarpophalangeal joint hyperextension angle were recorded as variables. Mann-Whitney U test or Fisher exact test was used for univariate analysis of the above factors, and then multivariate logistic regression analysis was performed to find out the factors associated with residual pain. RESULTS: The study included 60 thumbs of 53 patients. Eleven thumbs had postoperative residual pain. The surgery on the dominant hand was significantly associated with the presence of postoperative residual pain, especially in males. CONCLUSIONS: Dominant hand was associated with residual pain after LRTI for OA of the thumb CMC joint, although residual pain was minimal. Our findings will help in preoperative and postoperative counseling of patients. In the future, our results may also help select surgical procedures according to the patient's characteristics.

Factors associated with mobility decrease leading to disability: a cross-sectional nationwide study in Japan, with results from 8681 adults aged 20-89 years.

BACKGROUND: Mobility decrease leading to disability can gradually develop during early life, however, its related factors are not well clarified. Therefore, we investigate the related factors of mobility decrease at various levels, using nationwide data in Japan. METHODS: In total, 8681 independent community dwellers aged 20-89 years were analysed (average age, 51.6 years; 58.5% women). Three stages of mobility decrease were based on the locomotive syndrome risk test: Stage 1, emerging; Stage 2, progressing; Stage 3, progressed to restrict social engagement. Age was analysed using a simple quadratic function model. RESULTS: The prevalence of Stages 1-3 was 31.6% (n = 2746), 5.8% (n = 504), and 3.2% (n = 278), respectively. On the multivariable logistic regression, increased age in participants aged ≥40 years (stage 1: odds ratio[OR] 1.05-1.20, stage 2: OR 1.04-1.22, stage 3: OR 1.05-1.22), female (stage 1: OR 2.28, 95% confidence interval [CI] 1.99-2.61, stage 2: OR 2.40, 95% CI 1.77-3.25, stage 3: OR 1.80, 95% CI 1.19-2.72), overweight status (stage 1: OR 1.56, 95% CI 1.34-1.82, stage 2: OR 3.19, 95% CI 2.38-4.27, stage 3: OR 2.87, 95% CI 1.90-4.32), hypertension (stage 1: OR 1.20, 95% CI 1.01-1.41, stage 2: OR 1.99, 95% CI 1.49-2.64, stage 3: OR 2.10, 95% CI 1.44-3.05), and diabetes mellitus (stage 1: OR 1.62, 95% CI 1.17-2.24, stage 2: OR 1.57, 95% CI 0.93-2.66, stage 3: OR 2.10, 95% CI 1.13-3.90) were positively associated. The frequency of physical activity/sports, even a few per month, was inversely associated with all stages (stage 1: OR 0.59-0.72, stage 2: OR 0.50-0.67, stage 3: 0.36-0.53). A one-year increase in age had a stronger impact on mobility decrease in older adults than in younger ones. Increased age in participants aged < 40 years and smoking were associated with Stage 1, while intake of various foods was inversely associated with Stages 1 and 2. CONCLUSION: Increased age (< 40 years) was associated with emerging mobility decrease, while that (≥ 40 years) was associated with any levels of mobility decrease. Female, lifestyle habits, including physical activities and overweight status, were associated with mobility decrease at every level.

Factors Associated With Surgical Intervention for Osteoarthritis of the Thumb Carpometacarpal Joint.

PURPOSE: This retrospective study aimed to analyze the initial clinical factors associated with surgical intervention for osteoarthritis of the thumb carpometacarpal (CMC) joint. METHODS: The study included patients who first visited our hand surgery clinic, were given the diagnosis of osteoarthritis of the thumb CMC joint between May 2012 and January 2015, and were observed for more than 3 years. Patients were classified into 2 groups according to whether they had undergone surgery during the follow-up period. The following variables were extracted and included in a bivariate analysis: sex, age, age at onset, disease duration, dominant hand, pain visual analog scale (VAS) scores at rest and during use, night pain, Eaton classification, use of an orthosis, number of injections, tender area, range of motion, grip strength, pinch strength, Kapandji abduction index, palmar abduction distance, grind test results, CMC joint shape on radiographs, dorsal subluxation ratio, volar tilt of the metacarpal, presence or absence of ossicles, and the surgeon who recommended the surgery. Variables with P values less than .05 in the bivariate analysis were included in a logistic regression model. RESULTS: The study included 80 thumbs of 48 patients. Pain scores at rest and during use, and the dorsal subluxation ratio were identified as factors significantly associated with surgical intervention in the bivariate analysis. The subsequent logistic regression analysis including these factors as explanatory variables also identified the VAS score at rest and dorsal subluxation ratio as significantly associated with surgical intervention. CONCLUSIONS: The VAS score at rest and the dorsal subluxation ratio at the first clinical visit were associated with the likelihood of future surgical intervention within 3 years in patients with osteoarthritis of the thumb CMC joint. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.

A case of localized tracheobronchial relapsing polychondritis with positive matrilin-1 staining.

BACKGROUND: Relapsing polychondritis (RPC) is a rare progressive autoimmune disease characterized by inflammation in the cartilage of multiple organs. Tracheobronchial involvement appears in nearly half of RPC patients during the course of their disease and represents the main cause of death. Localized tracheobronchial RPC is much rarer, and the pathogenesis remains unclear. Matrilin-1 is a non-collagenous cartilage matrix protein and has been suggested to be a potent autoantigen that induces the airway disease of RPC in animal models. However, the expression of matrilin-1 in tracheobronchial tissue in human remains unclear. Therefore, we examined the expression of matrilin-1 in the tracheal and auricular tissues in a localized tracheobronchial RPC patient. CASE PRESENTATION: A 62-year-old man with systemic sclerosis presented with cough and dyspnea on exertion. The lung function test showed an expiratory flow limitation and chest computed tomography showed diffuse thickness from the trachea to the bronchiole. No other tests showed abnormal findings. To evaluate further, bronchoscopy was performed and endobronchial ultrasonography showed thickness in the fourth-marginal echo layer suggesting inflammation of the cartilage. However, the tracheal biopsy showed no specific findings. The subsequent surgical tracheal biopsies showed inflammatory cell infiltration with destruction of the cartilage. Neither auricular nor nasal deformity, except for a tracheobronchial lesion, was detected. Biopsy from the left auricular cartilage also did not show any inflammatory changes. Finally, we diagnosed the patient with localized tracheobronchial RPC. To address the hypothesis that autoimmunity against matrilin-1 is involved in the pathogenesis of localized tracheobronchial RPC, we evaluated the expression level of matrilin-1 in a tracheal and auricular specimen from this patient. Immunohistochemical staining with anti-matrilin-1 antibody showed matrilin-1 in the tracheal but not in the auricular cartilage. CONCLUSIONS: We first demonstrated the expression of matrilin-1 in tracheal but not in auricular cartilage in a localized tracheobronchial RPC patient. This result supports the possibility that matrilin-1 is involved in the pathogenesis of localized tracheobronchial RPC. However, this is only one case report and further observations will be needed to confirm this result.

Possible involvement of interleukin-18 in the pathology of hepatobiliary adverse effects related to treatment with ceritinib.

BACKGROUND: Ceritinib demonstrated a statistically significant effect on the progression-free survival versus chemotherapy in patients with advanced anaplastic lymphoma kinase (ALK) rearrangement in non-small cell lung cancer (NSCLC) as the first therapy or after previous treatment with crizotinib and one or two prior chemotherapy regimens in global phase 3 studies. However, some serious adverse effects related to ceritinib therapy were reported across these clinical studies. Among them, a grade 3 and 4 increase in hepatobiliary enzymes was one of the common adverse events related to treatment with ceritinib. However, the pathology remains unclear. Previously, increased Interleukin (IL)-18 was observed in both biliary duct disease and liver disease. Therefore, we hypothesized that IL-18 is involved in the pathology of hepatobiliary adverse effects related to treatment with ceritinib and evaluated the serum IL-18. CASE PRESENTATION: The patient was a 53-year-old Japanese woman that we previously reported as having severe hepatobiliary adverse effects related to ceritinib therapy. Laboratory data, CT and MRI were obtained at each time point. IL-18 was evaluated by ELISA method at each time point. Immunochemical staining of liver tissue was performed as a standard protocol using antibodies against IL-18. Our records showed that the levels of serum IL-18 increased from the early stage of hepatobiliary adverse effects related to the treatment with ceritinib and were became worse with an increase in hepatobiliary enzymes and the progression of imaging abnormalities in the bile duct. Furthermore, IL-18 positive cells were detected in the inflammatory sites around the interlobular bile duct of the liver tissue. CONCLUSION: Our case report shows that the increase of serum IL-18 had a positive correlation with the progression of severe hepatobiliary adverse effects related to treatment with ceritinib and the involvement of IL-18 in the hepatobiliary inflammation by pathological evaluation. These results suggest that IL-18 could be a useful surrogate marker for the hepatobiliary toxicity of ceritinib. However, this is only one case report and further prospective observations will complement our data in the future.

Development of a screening program to assess motor function in the adult population: a cross-sectional observational study.

BACKGROUND: Motor dysfunction is a major reason why the elderly lose their independence in their daily lives. The concept of locomotive syndrome has been proposed to describe the risk of mobility dependence caused by various locomotive organ disorders. The preservation of locomotive organs is now socially important in the middle-aged and geriatric population. Therefore, it is important to establish a screening program to evaluate motor function and related quality of life in a wide range of ages. METHODS: We propose a new set of pre-existing scales (the Two-Step test, Stand-Up test, and 25-question Geriatric Locomotive Function Scale) as screening tools to identify the population at high risk for locomotive syndrome. We performed a preliminary survey on 777 subjects who had no apparent disorders related to motor function. We also examined the reliability of the Two-Step test and Stand-Up test. RESULTS: We found that each scale did not show ceiling or floor effects in various age groups. Because the correlations between the three scales were significant but weak, we assume that each scale covers different aspects of mobility. The test-retest reliability was found to be satisfactory for the Two-Step test and the Stand-Up test. CONCLUSION: Our results suggest that our "Short Test Battery for Locomotive syndrome" is a feasible and reliable tool for screening the adult population as a preventative strategy for locomotive syndrome in a super-aged society.

Biophysical properties of intrinsically disordered p130Cas substrate domain--implication in mechanosensing.

Mechanical stretch-induced tyrosine phosphorylation in the proline-rich 306-residue substrate domain (CasSD) of p130Cas (or BCAR1) has eluded an experimentally validated structural understanding. Cellular p130Cas tyrosine phosphorylation is shown to function in areas without internal actomyosin contractility, sensing force at the leading edge of cell migration. Circular dichroism shows CasSD is intrinsically disordered with dominant polyproline type II conformations. Strongly conserved in placental mammals, the proline-rich sequence exhibits a pseudo-repeat unit with variation hotspots 2-9 residues before substrate tyrosine residues. Atomic-force microscopy pulling experiments show CasSD requires minimal extension force and exhibits infrequent, random regions of weak stability. Proteolysis, light scattering and ultracentrifugation results show that a monomeric intrinsically disordered form persists for CasSD in solution with an expanded hydrodynamic radius. All-atom 3D conformer sampling with the TraDES package yields ensembles in agreement with experiment when coil-biased sampling is used, matching the experimental radius of gyration. Increasing ß-sampling propensities increases the number of prolate conformers. Combining the results, we conclude that CasSD has no stable compact structure and is unlikely to efficiently autoinhibit phosphorylation. Taking into consideration the structural propensity of CasSD and the fact that it is known to bind to LIM domains, we propose a model of how CasSD and LIM domain family of transcription factor proteins may function together to regulate phosphorylation of CasSD and effect machanosensing.

Comparative study on the stiffness of transverse carpal ligament between normal subjects and carpal tunnel syndrome patients.

The purpose of this study was to compare the stiffness of the transverse carpal ligament (TCL) between healthy volunteers and carpal tunnel syndrome (CTS) patients using sonoelastography. We studied 17 healthy volunteers (four men, 13 women; range 37-84 years) and 18 hands of 13 patients with CTS (three men, ten women; range 41-79 years). Thickness and elasticity of the TCL were evaluated by sonoelastography. Elasticity was estimated by strain ratio of an acoustic coupler, which has a standardized elasticity as a reference medium, to the TCL (AC/T strain ratio). The AC/T strain ratios of the healthy volunteers and the CTS patients were 6.0 and 8.1, respectively (p = 0.030). The AC/T strain ratio showed a positive correlation with the duration of symptoms in the CTS patients (p = 0.035, r = 0.50). We concluded that increased stiffness of the TCL could be one of the causes for CTS.

Ultrasonographic evaluation of displaced neurovascular bundle in Dupuytren disease.

PURPOSE: Neurovascular injury is a serious complication after surgery for Dupuytren disease. The purpose of this study was to evaluate the relationship between the cord and the neurovascular bundle ultrasonographically. METHODS: We included 22 healthy volunteers and 14 Dupuytren disease patients (25 fingers) in this study. We evaluated the cord and the digital artery with high-resolution ultrasound. We first investigated the effect of the angle of metacarpophalangeal joint on the position of the radial and ulnar digital arteries in volunteers without evidence of Dupuytren disease. We compared 3 parameters of the radial and ulnar digital arteries, including differences in depth, differences in lateral shift, and the shape of the cross-section of the artery, between volunteers and patients with Dupuytren disease. RESULTS: None of these parameters changed with flexion of the metacarpophalangeal joint of 0°, 30°, and 60°. Digital arteries and cords could be identified ultrasonographically in all patients, and we confirmed ultrasonographic findings by operative findings in 13 fingers. We classified the fingers into 3 subgroups based on the ultrasonographic findings: type A (n = 13), in which the cord was above the artery; type B (n = 5), in which the cord was below the artery; and type C (n = 7), in which the cord was located between the radial and ulnar digital arteries. Types A, B, and C corresponded to natatory cord/abductor digiti minimi cord, spiral cord, and central cord, respectively. Comparisons among volunteers and patient subgroups showed that the difference in depth in type B patients was significantly larger than that of the other groups. When we set the cutoff point of the difference in depth to 3 mm, sensitivity and specificity to detect the spiral cord were 80% and 76%, respectively. CONCLUSIONS: The relationship between the neurovascular bundle and the type of Dupuytren disease cord can be evaluated by high-resolution ultrasound. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic III.

Stiffness of the first annular pulley in normal and trigger fingers.

PURPOSE: The cause of snapping in trigger finger is not clearly understood. The purpose of this study was to investigate the influence of stiffness of the first annular pulley on snapping in trigger finger patients with sonoelastography, a new technique for quantitative assessment of the stiffness of soft tissues. METHODS: We first studied 20 healthy volunteers (all women, aged 24-78 y) to define the change of stiffness with aging and with specific fingers. We then studied 10 digits of 9 patients (all women, aged 60-78 y) with trigger finger that involved middle or ring fingers. Thickness and stiffness were evaluated by sonoelastography. Stiffness was estimated by strain ratio of subcutaneous fat to the pulley (F/P strain ratio). The patients were treated with corticosteroid injection, and the measurement was repeated 3 weeks later. RESULTS: In the healthy volunteers, both thickness and F/P strain ratio showed a positive correlation with age. There was no difference between the middle and ring fingers. In trigger finger patients, the pulley thicknesses of the affected finger and the adjacent normal finger before corticosteroid injection were 0.99 ± 0.19 mm and 0.60 ± 0.14 mm (mean ± SD), respectively. The F/P strain ratios of the affected finger and the adjacent normal finger before the injection were 4.2 ± 1.3 and 2.4 ± 0.63, respectively. Three weeks after the injection, snapping disappeared in all patients, the pulley thickness decreased to 0.61 ± 0.15 mm, and the F/P strain ratio decreased to 2.5 ± 0.68. The cross-sectional area for flexor tendons within the pulley did not change after the injection. CONCLUSIONS: Increased stiffness and thickening of the A1 pulley are considered to be causes for snapping in trigger finger, and corticosteroid injection can alleviate snapping by changing these 2 features.

Reduction of Peritendinous adhesions by hydrogel containing biocompatible phospholipid polymer MPC for tendon repair.

BACKGROUND: Peritendinous adhesions are serious complications after surgical repair of tendons. As an anti-adhesion material, we focused on 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer, our original biocompatible polymer, and prepared an aqueous solution of MPC-containing polymer called poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate-co-p-vinylphenylboronic acid) (PMBV), which can be formed into hydrogel properties by mixture with another aqueous polymer, poly(vinyl alcohol) (PVA). The objective of the present study was to examine the possible application of the MPC hydrogel for the reduction of peritendinous adhesions. METHODS: the effects of the hydrogel on peritendinous adhesions and tendon healing were examined by means of histological and mechanical analyses in a rat Achilles tendon model and a rabbit flexor digitorum profundus tendon model. Cell migration and viability were examined with use of fibroblastic NIH3T3 cells cultured in a double chamber dish. RESULTS: among the concentrations examined, 2.5% and 5.0% PMBV formed hydrogel properties immediately after mixing with 2.5% PVA and maintained a honeycomb microstructure with nanometer-scaled pores for three weeks after implantation. In animal models, the hydrogel formed from 5.0% PMBV remained at the sutured site during the critical period up to three weeks and disappeared by six weeks. The MPC hydrogel reduced the peritendinous adhesions histologically and mechanically by >25% at three weeks, without impairing tendon healing as determined with mechanical analyses. In the cell culture, cell migration was reduced by the MPC hydrogel, although cell viability was unaffected, indicating physical prevention, rather than cytotoxicity, to be the anti-adhesion mechanism. CONCLUSIONS: the MPC hydrogel that was formed by a local injection and mixture of two aqueous solutions, 5.0% PMBV and 2.5% PVA, reduced peritendinous adhesions without impairing tendon healing. This effect may be due to its excellent biocompatibility without a foreign-body reaction and the formation of a microstructure that physically prevents passage of cells but allows cytokines and growth factors to pass for healing. CLINICAL RELEVANCE: this nanotechnology could potentially improve the quality of surgical repair of tendon, especially the zone-II area of the digital flexor tendon.

The prevention of peritendinous adhesions by a phospholipid polymer hydrogel formed in situ by spontaneous intermolecular interactions.

Preventing peritendinous adhesions after surgical repair of tendon is difficult. In order to establish an ideal anti-adhesion material, we prepared a spontaneously forming hydrogel by mixing the aqueous solutions of two polymers, poly(MPC-co-methacrylic acid) (PMA) and amphiphilic poly(MPC-co-n-butyl methacrylate) (PMB), in the presence of Fe(3+). This PMA/PMB/Fe(3+) hydrogel (MPC polymer hydrogel) had a honeycomb microstructure with nanometer-scale pores, which resist cell invasion but allow the passage of cytokines and growth factors for tendon healing. The dissociation rate of the hydrogel could be controlled by changing Fe(3+) concentration, and by examining the viscoelasticity of the hydrogel, we determined the optimal Fe(3+) concentration to be 0.05 M. We then examined the effects of the in situ application of this MPC polymer hydrogel containing 0.05 M Fe(3+) by using two animal models: the rat Achilles tendon model and the chicken flexor digitorum profundus tendon model. In both models, macroscopic and histological observation revealed that peritendinous adhesions were significantly decreased by the hydrogel application. Mechanical analyses revealed that the hydrogel prevented peritendinous adhesions but did not affect the tendon healing. Because of its characteristic microstructure and excellent biocompatibility, we believe that the MPC polymer hydrogel will be ideal for preventing peritendinous adhesions.

Rupture of the extensor pollicis longus tendon in trapeziometacarpal joint osteoarthritis: case report.

We report a case of rupture of the EPL tendon that occurred in a patient with trapeziometacarpal joint osteoarthritis. We assume that the rupture was secondary to attrition caused by a bony protrusion of advanced trapeziometacarpal joint osteoarthritis.