Different Pattern of T-Score Discordance between Patients with Atypical Femoral Fracture and Femur Neck Fracture.

BACKGROUND: Our study evaluated the prevalence and pattern of T-score discordance between the spine and hip in Korean patients with atypical femoral fracture (AFF) and femur neck fracture (FNF). METHODS: A total of 49 patients (all women) who were treated for AFF and 1:3 matched 147 female patients with FNF were included from January 2012 to August 2022. A discordance of more than 1.5 between lumbar spine and femur neck bone mineral density (BMD) was defined as a difference and divided into 3 groups: lumbar low (LL; lumbar BMD is less than femur neck BMD), no discordance (ND), and femur neck low (FL; femur neck BMD is less than lumbar BMD). We compared the prevalence and pattern of discordance between 2 groups, and the associated risk factors of T-score discordance among the subjects were evaluated using regression analysis. RESULTS: The prevalence of discordance was significantly higher in patients with AFF (51%) than in those with FNF (25.2%; p<0.001). LL discordance was found in 46.9% of the patients with AFF but only 4.8% in those with FNF. Conversely, FL discordance was found in 4.1% of the patients with AFF and 20.4% in those with FNF, respectively. No specific risk factor was found as T-score discordance in the 2 groups. CONCLUSIONS: Clinicians should be aware that the pattern of T-score discordance can vary depending on the location of osteoporotic fractures. In addition, a longitudinal study would be necessary to verify the pattern of T-score discordance related to the osteoporotic fracture location.

Prevalence and Risk Factors of T-Score Spine-Hip Discordance in Patients with Osteoporotic Vertebral Compression Fracture.

BACKGROUND: T-score discordance between the spine and hip is commonly observed when dual energy X-ray absorptiometry (DXA) is used to diagnose osteoporosis. However, information is scarce regarding the prevalence and risk factors for this problem in Korea. This study evaluated the prevalence of major/minor discordance and associated risk factors in elderly Korean patients with osteoporotic vertebral compression fractures (OVCFs). METHODS: This study included 200 patients (37 men, 163 women) treated for thoracic or lumbar compression fractures between January 2015 and August 2021. DXA was performed to examine T-scores and determine the prevalence of discordance, defined as a difference between the T-score categories of the femur and spine in the same individual. The t-tests, χ2 tests, and regression analyses were used to assess the associated risk factors of T-score discordance among the subjects. RESULTS: T-score concordance, minor discordance, and major discordance were observed in 137 (68.5%), 59 (29.5%), and 4 (2%) patients with OVCFs, respectively. The spinal T-score was lower than the femoral T-score in all major discordance and 81.3% (48/59) of minor discordant cases. Overall, the only factor related to T-score discordance was the age at fracture (odds ratio, -0.01; P=0.014). CONCLUSIONS: The results of this study showed that a significant number of subjects (31.5%) showed spine-hip discordance, even with a mean age in their 80s. More attention should be paid to the appropriate evaluation and management of elderly patients with OVCFs. Moreover, a longitudinal study is necessary to verify the clinical importance of T-score discordance in this population.

Does Bone Mineral Density Differ between Fan-Beam and Pencil-Beam?: A Meta-Analysis and Systemic Review.

BACKGROUND: Dual energy X-ray absorptiometry (DXA) has evolved from pencil-beam (PB) to narrow fan-beam (FB) densitometers. We performed a meta-analysis of the available observational studies to determine how different modes of DXA affect bone mineral density (BMD) measurements. METHODS: A total of 1,233 patients (808 women) from 14 cohort studies were included. We evaluated the differences in BMD according to the DXA mode: PB and FB. Additionally, we evaluated the differences in BMD between the 2 types of FB mode: FB (Prodigy) and the most recent FB (iDXA). Pairwise meta-analysis was performed, and weighted mean differences (WMD) were calculated for (total lumbar, total hip, and total body). RESULTS: No significant difference was observed in total lumbar (pooled WMD, -0.013; P=0.152) and total hip BMD (pooled WMD, -0.01; P=0.889), between PB and FB. However, total body BMD was significantly lower in the PB compared to the FB group (pooled WMD, -0.014; P=0.024). No significant difference was observed in lumbar BMD (pooled WMD, -0.006; P=0.567), total hip (pooled WMD, -0.002; P=0.821), and total body (pooled WMD, 0.015; P=0.109), between Prodigy and iDXA. CONCLUSIONS: The results of this study warrant the recommendation that correction equations should not be used when comparing BMD from different modes. Further research is still needed to highlight the ways in which differences between DXA systems can be minimized.

Preoperative Pain Sensitization Is Associated With Postoperative Pillar Pain After Open Carpal Tunnel Release.

BACKGROUND: Postoperative pillar pain (deep-seated wrist pain worsened by leaning on the heel of the hand) sometimes occurs after carpal tunnel release (CTR), leading to weakness in the hand and delayed return to work. Increased pain sensitivity has been found to be associated with worse symptoms and poorer treatment response in a number of chronic musculoskeletal conditions, but few studies have investigated the association of pain sensitization with pillar pain after CTR. QUESTIONS/PURPOSES: (1) Is preoperative pain sensitization in patients with carpal tunnel syndrome (CTS) associated with increased severity of pillar pain after open CTR? (2) What other demographic, electrophysiological, or preoperative clinical characteristics are associated with pillar pain after CTR? METHODS: Over a 35-month period, one surgeon performed 162 open carpal tunnel releases. Patients were eligible if they had sufficient cognitive and language function to provide informed consent and completed a self-reported questionnaire; they were not eligible if they had nerve entrapment other than CTR or if the surgery was covered by workers compensation insurance. Based on these criteria, 148 (91%) were approached for this study. Of those, 17 (9%) were lost to followup before 12 months, leaving 131 for analysis. Their mean age was 54 years (range, 32-78 years), and 81% (106 of 131) were women; 34% (45 of 131) had less than a high school education. We preoperatively measured pain sensitization by assessing the patients' pressure pain thresholds by stimulating pressure-induced pain in the pain-free volar forearm and administering a self-reported Pain Sensitivity Questionnaire minor subscale, an instrument that assesses pain intensity in daily life situations. We evaluated postoperative pillar pain using the "table test" (having the patient lean on a table with their weight on their hands placed on the table's edge with elbows straight) with an 11-point ordinal scale at 3, 6, and 12 months after their surgical procedures. We conducted bivariate and multivariable analyses to determine whether the patients' clinical, demographic, and pain sensitization factors were associated with their postoperative pillar pain severity after CTR. RESULTS: After controlling for relevant confounding variables such as age, education level, and functional states, we found that increased pillar pain severity was associated with the pressure pain threshold (ß = -1.02 [-1.43 to -0.61], partial R = 11%, p = 0.021) and Pain Sensitivity Questionnaire minor (ß = 1.22 [0.73-1.71], partial R = 17%, p = 0.013) at 3 months, but by 6 months, only Pain Sensitivity Questionnaire minor (ß = 0.92 [0.63-1.21], partial R = 13%, p = 0.018) remained an associated variable for pillar pain. Additionally, gender (women) was associated with increased pain severity at 3 (ß = 0.78 [0.52-1.04], partial R = 9%, p = 0.023) and 6 months (ß = 0.72 [0.41-1.01], partial R = 8%, p = 0.027). At 3 months, pressure pain threshold, Pain Sensitivity Questionnaire minor, and gender (women) collectively accounted for 37% of the variance in pillar pain severity; at 6 months, Pain Sensitivity Questionnaire minor and gender (women) accounted for 21% of the variance, but no relationship between those factors and pillar pain was observed at 12 months. CONCLUSIONS: Gender (women) and preoperative pain sensitization measured by pressure pain threshold and self-reported Pain Sensitivity Questionnaire were associated with pillar pain severity up to 3 and 6 months after CTR, respectively. However, the influence of pain sensitization on pillar pain was diminished at 6 months and it did not show persistent effects beyond 12 months. Pain sensitization seems to be more important in the context of recovery from surgical intervention (in the presence of a pain condition) than in healthy states, and clinicians should understand the role of pain sensitization in the postoperative management of CTS. Future research may be needed to determine if therapeutic interventions to reduce sensitization will decrease the risk of pillar pain. LEVEL OF EVIDENCE: Level III, prognostic study.

Patients With Limited Health Literacy Have Similar Preferences but Different Perceptions in Surgical Decision-making for Carpal Tunnel Release.

BACKGROUND: Health literacy is the ability to obtain, process, and understand health information needed to make appropriate health decisions. The proper comprehension by patients regarding a given disease, its treatment, and the physician's instructions plays an important role in shared decision-making. Studies have disagreed over the degree to which differences in health literacy affect patients' preferences for shared decision-making; we therefore sought to evaluate this in the context of shared decision-making about carpal tunnel release. QUESTIONS/PURPOSES: (1) Do patients with limited health literacy have different preferences of shared decision-making for carpal tunnel release than those with greater levels of health literacy? (2) How do patients with limited health literacy retrospectively perceive their role in shared decision-making after carpal tunnel release? METHODS: Over a 32-month period, one surgeon surgically treated 149 patients for carpal tunnel syndrome. Patients were eligible if they had cognitive and language function to provide informed consent and complete a self-reported questionnaire and were not eligible if they had nerve entrapment other than carpal tunnel release or had workers compensation issues; based on those, 140 (94%) were approached for study. Of those, seven (5%) were lost to followup before 6 months, leaving 133 for analysis here. Their mean age was 55 years (range, 31-76 years), and 83% (111 of 133) were women. Thirty-three percent (44 of 133) of patients had less than a high school education. Health literacy was measured according to the Newest Vital Sign during the initial visit, and a score of ≤ 3 was considered limited health literacy. Forty-four percent of patients had limited health literacy. The Control Preferences Scale was used for patients to indicate their preferred role in surgical decision-making preoperatively and to assess their perceived level of involvement postoperatively. Bivariate and multivariable analyses were performed to determine whether patients' clinical, demographic, and health literacy factors accounted for the preoperative preferences and postoperative assessments of their role in shared decision-making. A total of 133 patients would provide 94% power for a medium effect size for linear regression with five main predictors. RESULTS: We found no differences between patients with lower levels of health literacy and those with greater health literacy in terms of preferences of shared decision-making for carpal tunnel release (3.0 ± 1.6 versus 2.7 ± 1.4; mean difference, 0.3; 95% confidence interval, -0.2 to 0.8; p = 0.25). A history of surgical procedures (coefficient = -0.32, p < 0.01) and a lower Disabilities of the Arm, Shoulder and Hand score (coefficient = 0.17, p = 0.02) were independently associated with a preference for an active role in shared decision-making. However, patients with limited health literacy (coefficient = -0.31, p = 0.01) and an absence of a caregiver (coefficient = -0.28, p = 0.03) perceived a more passive role in actual decision-making. CONCLUSIONS: Physicians should be aware of the discrepancy between preferences and perceptions of shared decision-making among patients with limited health literacy, and physicians should consider providing a decision aid tailored to basic levels of health literacy to help patients achieve their preferred role in decision-making. LEVEL OF EVIDENCE: Level II, prognostic study.

Factors influencing functional outcome of proximal interphalangeal joint collateral ligament injury when treated with buddy strapping and exercise.

STUDY DESIGN: Prospective cohort. INTRODUCTION AND PURPOSE: This study evaluates the factors influencing treatment outcomes of proximal interphalangeal (PIP) joint collateral ligament injuries when treated with buddy strapping. METHODS: Sixty-seven patients treated with buddy strapping for a PIP joint injury were enrolled. The finger range of motion (ROM), grip strength, and a Quick Disability of the Arm, Shoulder, and Hand (QuickDASH) score were assessed at 3 and 6 months after the initial injury. The factors that were assessed for their influence on the functional outcomes included age, sex, hand dominance, affected finger, type of injury, injury severity, time to treatment, the duration of buddy strapping, and exercise training. RESULTS: Buddy strapping for PIP joint injuries led to satisfactory results with 77% recovery of grip strength, 84% recovery in ROM, and mean QuickDASH scores of 14 at 6 months. A decrease in grip strength was associated with an increase in age and injury severity at 6 months, and these 2 factors accounted for 22% of the variance in the grip strength. A decrease in ROM was associated with the delayed treatment, which accounted for 18% of the variance in ROM at 6 months. An increased disability was associated with delayed treatment, female gender, and radial digit injury at 3 months, and these 3 factors accounted for 37% of the variance in disability. At 6 months, only the delayed treatment remained an associated factor, which accounted for 20% variance in disability. DISCUSSION AND CONCLUSIONS: PIP collateral ligament injuries had very good outcomes with buddy strapping. However, delayed treatment was significantly associated with poor functional outcomes in terms of the ROM and disability. An increase in age and injury severity were associated with lower grip strength up to 6 months, whereas a female gender and radial digit injury were associated with an increased disability up to 3 months. LEVEL OF EVIDENCE: 2.

Focal Eosinophilic Myositis of the Hand Presenting as a Refractory Pyogenic Infection.

Eosinophilic myositis is a rare disorder in which eosinophils infiltrate muscle and supporting connective tissue structures. The disorder can be localized or diffuse, and it may be associated with various systemic features resembling autoimmune disease. Focal eosinophilic myositis is the most limited form of eosinophilic myositis, for which muscle involvement is generally limited to the lower extremity. We report on a rare case of focal eosinophilic myositis of the interosseous muscles of the hand, which presented as a refractory, pyogenic hand infection.

Effect of health literacy on adherence to osteoporosis treatment among patients with distal radius fracture.

Patients with inadequate health literacy, those with medical comorbidities, or those with a previous history of adverse drug events have a higher likelihood of non-adherence to osteoporosis treatment after sustaining a distal radius fracture. INTRODUCTION: Patients with a distal radial fracture (DRF) have a higher risk of subsequent fractures, which provides an important opportunity to begin treatment for osteoporosis. This study assessed the effect that health literacy of patients suffering from a DRF has on the subsequent adherence to osteoporosis treatment. METHODS: A total of 116 patients (female, over 50 years of age) presenting a DRF caused by low-energy trauma were enrolled. Their health literacy was measured using the Newest Vital Sign (NVS). Alendronate (70 mg, orally, once weekly) was prescribed to all patients for 1 year, and adherence was defined as taking at least 80% of the tablets for 12 months and returning for the visit on month 12. Multivariable analyses were conducted to determine whether the patients' clinical, demographic, and health literacy factors influenced their adherence to osteoporosis treatment. RESULTS: About half (52%) of the participants who sustained a DRF exhibited an inadequate health literacy, and the rate of non-adherence to osteoporosis treatment was 38%. The rate of non-adherence for patients with inadequate literacy was significantly higher than for those with appropriate literacy (47 vs. 29%, p = 0.04). The results of the regression analysis indicate that limited health literacy, the presence of comorbidities, and prior history of adverse drug events are associated with a higher likelihood of non-adherence to osteoporosis treatment after sustaining a DRF. CONCLUSIONS: Patients with inadequate health literacy, adverse drug events, or medical comorbidities had higher rates of non-adherence with alendronate treatment after sustaining a DRF. Further research is needed to show whether improvements in patient comprehension via informational intervention in patients with a DRF will improve adherence to osteoporosis treatment.

Low Median Nerve Palsy as Initial Manifestation of Churg-Strauss Syndrome.

Anterior interosseous nerve (AIN) syndrome is typically characterized by forearm pain and partial or complete dysfunction of the AIN-innervated muscles. Although the exact etiology and pathophysiology of the disorder remain unclear, AIN syndrome is increasingly thought to be an inflammatory condition of the nerve rather than a compressive neuropathy because the symptoms often resolve spontaneously following prolonged observation. However, peripheral neuropathy can be 1 of the first symptoms of systemic vasculitis that needs early systemic immunotherapy to prevent extensive nerve damage. Churg-Strauss syndrome (CSS; eosinophilic granulomatosis with polyangiitis) is 1 type of primary systemic vasculitis that frequently damages the peripheral nervous system. CSS-associated neuropathy usually involves nerves of the lower limb, and few studies have reported on the involvement of the upper limb alone. We report on a rare case of low median nerve palsy as the initial manifestation of CSS. The patient recovered well with early steroid treatment for primary systemic vasculitis.

Evaluation of sarcopenia in patients with distal radius fractures.

Sarcopenia is more prevalent in patients with distal radius fracture (DRF) than in age- and sex-matched controls. Lower appendicular mass index in men and weaker grip strength in both men and women increase the likelihood of DRF. INTRODUCTION: Sarcopenia is a core component of physical frailty that predisposes older people to falls and negatively impacts the activities of daily living. The objectives of this study were to compare the prevalence of sarcopenia in patients with DRF with that in age- and sex-matched controls without DRF; and evaluate the association between sarcopenia and the occurrence of DRF. METHODS: We prospectively recruited 132 patients over 50 years of age who sustained DRF due to fall and 132 age- and sex-matched controls without DRF. A definition of sarcopenia was based on the consensus of the Asian Working Group for Sarcopenia. Sarcopenic components including appendicular lean body mass, grip strength, and gait speed were compared between the two groups. Other factors assessed for the occurrence of DRF were age, gender, body mass index (BMI), lumbar, and hip bone mineral density (BMD) values. A conditional logistic regression analysis was conducted to evaluate the associations between sarcopenia and the occurrence of DRF. RESULTS: A total of 39 (30%) of 132 DRF patients were sarcopenic, whereas 23 (17%) of the 132 controls were within the sarcopenic criteria (p = 0.048). The patient group had significantly lower lean body mass and weaker grip strength than those of the control group. However, there was no significant difference in gait speed between the two groups. According to regression analysis, lower appendicular mass index in men was associated with an increased incidence of DRF (odds ratio [OR] = 0.84, 95% confidence interval [CI] = 0.72, 0.95) while weaker grip strength and lower total hip BMD values were associated with the occurrence of DRF in both men (OR = 0.77, 95% CI = 0.63, 0.92; and OR = 0.79, 95% CI = 0.64, 0.94, respectively) and women (OR = 0.78, 95% CI = 0.64, 0.93, and OR = 0.73, 95% CI = 0.52, 0.92, respectively). CONCLUSIONS: Sarcopenia is more prevalent in patients with DRF than in age- and sex-matched controls. Lower appendicular mass in men, weaker grip strength, and lower hip BMD in both men and women increase the likelihood of DRF.

Development of a decellularization method to produce nerve allografts using less invasive detergents and hyper/hypotonic solutions.

BACKGROUND: Here, we describe a novel method of processing decellularized nerve grafts using osmotic effects of hypotonic and hypertonic solutions and Triton X-100 (a nonionic detergent) and CHAPS (an amphoteric detergent). MATERIALS AND METHODS: To evaluate decellularization, the devised method and Hudson's method were compared with respect to remaining cellular components (as assessed by H&E staining and S-100 immunoreactivity) and extracellular matrix structural integrity (as assessed by H&E staining and laminin immunoreactivity) by using rat sciatic nerves. In addition, a 1.5-cm sciatic nerve gap rat model was treated by implanting decellularized nerve grafts prepared using the devised method, Hudson's method, or an autograft to evaluate nerve regeneration. Nerve histomorphometry of distal stumps and wet muscle mass were evaluated at 12 weeks after implantation. RESULTS: The devised method produced outcomes similar to those of Hudson's method in terms of cellular component removal, but the devised method was significantly better in terms of ECM preservation. Histomorphometric study showed that the devised method produced significantly fewer nerve fiber and axonal densities than autografting, but much more than Hudson's method. The wet muscle mass of the devised method was also significantly lower than that of autografting, but much higher than that of Hudson's method. CONCLUSION: The described process for producing decellularized nerve grafts yielded better outcomes with respect to peripheral nerve regeneration than the established ionic detergent-based methods in a rat model. This study indicates that decellularized nerve grafts produced in this manner show favorable nerve regeneration used for bridging nerve gaps.

Changes in Clinical Symptoms, Functions, and the Median Nerve Cross-Sectional Area at the Carpal Tunnel Inlet after Open Carpal Tunnel Release.

BACKGROUND: The aim of this study was to investigate the relationship between clinical symptoms and cross-sectional area (CSA) of the median nerve at the carpal tunnel inlet before and after open carpal tunnel release (CTR). METHODS: Thirty-two patients (53 hands) that underwent open CTR for idiopathic carpal tunnel syndrome were prospectively enrolled. Median nerve CSA at the carpal tunnel inlet was measured preoperatively and at 2 and 12 weeks after CTR by high resolution ultrasonography. The Boston carpal tunnel questionnaire (BCTQ) was also completed at these times. RESULTS: BCTQ symptom (BCTQ-S) score was significantly improved at 2 weeks postoperatively, but BCTQ function (BCTQ-F) score and CSA were significantly improved at 12 weeks postoperatively. Preoperative CSA was significantly correlated with preoperative BCTQ-S and BCTQ-F scores but was not significantly correlated with postoperative BCTQ scores or postoperative changes in BCTQ scores. Postoperative median nerve CSA was not significantly correlated with postoperative BCTQ-S or BCTQ-F scores, and postoperative changes in median nerve CSA were not significantly correlated with postoperative changes in BCTQ-S or BCTQ-F scores. CONCLUSIONS: The study shows clinical symptoms resolve rapidly after open CTR, but median nerve swelling and clinical function take several months to recover. In addition, preoperative median nerve swelling might predict preoperative severities of clinical symptoms and functional disabilities. However, postoperative reductions in median nerve swelling were not found to reflect postoperative reductions in clinical symptoms or functional disabilities.

Effect of calcium phosphate bone cement augmentation on volar plate fixation of unstable distal radial fractures in the elderly.

BACKGROUND: Calcium phosphate bone cement increases the stability of implant-bone constructs in patients with an osteoporotic fracture. The purpose of this randomized study was to determine whether augmentation of volar locking plate fixation with calcium phosphate bone cement has any benefit over volar locking plate fixation alone in patients older than sixty-five years of age who have an unstable distal radial fracture. METHODS: Forty-eight patients (fifty unstable distal radial fractures) were recruited for this study. The mean patient age was seventy-three years. Surgical procedures were randomized between volar locking plate fixation alone (Group 1) and volar locking plate fixation with injection of calcium phosphate bone cement (Group 2). The patients were assessed clinically at three and twelve months postoperatively. Clinical assessments included determinations of grip strength, wrist motion, wrist pain, modified Mayo wrist scores, and Disabilities of the Arm, Shoulder and Hand (DASH) scores. Radiographic evaluations were performed immediately postoperatively and at one year following surgery. The adequacy of the reduction was assessed by measuring radial inclination, volar angulation, and ulnar variance. RESULTS: The two groups were comparable with regard to age, sex, fracture type, injury mechanism, and bone mineral density. No significant differences were observed between the groups with regard to the clinical outcomes at the three or twelve-month follow-up examination. No significant intergroup differences in radiographic outcomes were observed immediately after surgery or at the one-year follow-up visit. Furthermore, no complication-related differences were observed, and there were no nonunions. CONCLUSIONS: Augmentation of metaphyseal defects with calcium phosphate bone cement after volar locking plate fixation offered no benefit over volar locking plate fixation alone in elderly patients with an unstable distal radial fracture.

Reliability and Validity of Thoracolumbar Injury Classification and Severity Score (TLICS).

STUDY DESIGN: A new classification system for throacolumbar spine injury, Thoracolumbar Injury Classification and Severity Score (TLICS) was evaluated retrospectively. PURPOSE: To evaluate intrarater and interrater reliability of newly proposed TLICS schemes and to estimate validity of TLICS's final treatment recommendation. OVERVIEW OF LITERATURE: Despite numerous literature about thoracolumbar spine injury classifications, there is no consensus regarding the optimal system. METHODS: Using plain radiographs, computed tomography scanning, magnetic resonance imaging, and medical records, 3 clssifiers, consisting of 2 spine surgeons and 1 senior orthopaedic surgery resident, reviewed 114 clinical thoracolumbar spine injury cases retrospectively to classify and calculate injury severity score according to TLICS. This process were repeated on 4 weeks intervals and the scores were then compared with type of treatment that patient ultimately received. RESULTS: The intrarater reliability of TLICS was substantial agreement on total score and injury morphology, almost perfect agreement on integrity of the posterior ligament complex (PLC) and neurologic status. The interrater reliability was substantial agreement on injury morphology and integrity of the PLC, moderate agreement on total score, almost perfect agreement on neurologic status. The TLICS schems exhibited satisfactory overall validity in terms of clinical decision making. CONCLUSIONS: The TLICS was demonstrated acceptable intrarater and interrater reliability and satisfactory validity in terms of treatment recommendation.

Oxidative stress in subsynovial connective tissue of idiopathic carpal tunnel syndrome.

Ischemic-reperfusion injury is thought to be a cause of idiopathic carpal tunnel syndrome (CTS). The purpose of this study was to determine whether oxidative stress caused by ischemia-reperfusion injury in subsynovial connective tissue is associated with idiopathic CTS and its symptoms. Bioptic samples of tenosynovial tissue were collected from 20 idiopathic CTS patients during surgery. Control specimens of tenosynovial tissue were collected from eight non-CTS patients. Analysis included histological and immunohistochemical examination for the distribution of endothelial nitric oxide synthase (eNOS), nuclear factor (NF)-κß, and transforming growth factor (TGF)-ß RI in subsynovial connective tissues. Histological examinations showed a marked increase in fibroblast density and vascular proliferation in specimens from CTS patients. The expressions of eNOS, NF-κß, and TGF-ß RI in fibroblasts and vascular endothelial cells of subsynovial connective tissues of patients were significantly higher than in those of controls. A significant positive correlation was found between the subjective symptom severity of CTS, and the immunoreactivities of eNOS and NF-κß. This study suggests that oxidative stress in subsynovial connective tissue is related to CTS and its symptoms.

Should an ulnar styloid fracture be fixed following volar plate fixation of a distal radial fracture?

BACKGROUND: Ulnar styloid fractures often occur in association with distal radial fractures. The purpose of this study was to determine whether an associated ulnar styloid fracture following stable fixation of a distal radial fracture has any effect on wrist function or on the development of chronic distal radioulnar joint instability. METHODS: One hundred and thirty-eight consecutive patients who underwent surgical treatment of an unstable distal radial fracture were included in this study. During surgery, none of the accompanying ulnar styloid fractures were internally fixed. Patients were divided into nonfracture, nonbase fracture, and base fracture groups, on the basis of the location of the ulnar styloid fracture, and into nonfracture, minimally displaced (< or =2 mm), and considerably displaced (>2 mm) groups, according to the amount of ulnar styloid fracture displacement at the time of injury. Postoperative evaluation included measurement of grip strength and wrist range of motion; calculation of the modified Mayo wrist score and Disabilities of the Arm, Shoulder and Hand score; as well as testing for instability of the distal radioulnar joint at a mean of nineteen months postoperatively. RESULTS: Ulnar styloid fractures were present in seventy-six (55%) of the 138 patients. Forty-seven (62%) involved the nonbase portion of the ulnar styloid and twenty-nine (38%) involved the base of the ulnar styloid. Thirty-four (45%) were minimally displaced, and forty-two (55%) were considerably (>2 mm) displaced. We did not find a significant relationship between wrist functional outcomes and ulnar styloid fracture level or the amount of displacement. Chronic instability of the distal radioulnar joint occurred in two wrists (1.4%). CONCLUSIONS: An accompanying ulnar styloid fracture in patients with stable fixation of a distal radial fracture has no apparent adverse effect on wrist function or stability of the distal radioulnar joint.

Stress fracture of the pelvic wing-sacrum after long-level lumbosacral fusion: a case report.

STUDY DESIGN: A case report of transverse stress fracture of the pelvic wing-sacrum after long-level lumbosacral fusion. OBJECTIVE: To report this rare complication of long-level lumbosacral fusion. SUMMARY OF BACKGROUND DATA: There are a number of well-described complications of instrumented lumbosacral fusion, including delayed stress fracture of the pelvis. A bilateral pelvic wing-sacrum transverse stress fracture after long-level lumbosacral fusion has not been previously reported to our knowledge. METHODS: Radiography and computed tomography were used to confirm the diagnosis. Long lumbosacral fusion and a pelvic wing-sacrum fracture were shown. RESULTS: A 48-year-old woman underwent several revision spinal surgeries for collapse or instability occurring at the adjacent levels. She presented with low back and bilateral buttock pain with slow progression after last surgery. A bilateral transverse pelvic wing-sacrum stress fracture was found on plain radiographs 7 months later. CONCLUSIONS: Stress fracture of bilateral pelvic wing-sacrum can occur as a potential source of late pain after long fusions of the lumbosacral spine. A better understanding of the related biomechanical forces and preoperative risk factors may identify patients at risk and may aid in surgical planning. There are few reports of pelvic stress fracture as a complication of lumbosacral fusion, and it is typically described as a late occurrence. We present the occurrence of a bilateral pelvic wing-sacrum transverse stress fracture, not previously discussed to our knowledge.

A biomechanical comparison of calf versus cadaver lumbar spine models.

STUDY DESIGN: Biomechanical flexibility tests were performed using calf and human cadaveric lumbar spine models to investigate the effect of anatomic differences. OBJECTIVES: The purpose is to determine if differences exist in biomechanical flexibility testing results between calf and human cadaveric spines when using identical methods and instrumentation. SUMMARY OF BACKGROUND DATA: Calf spines are commonly used in biomechanical research as a substitute for human cadaveric spines in an attempt to reduce expense and specimen variability. Despite widespread use, the validity of this model has not been thoroughly investigated. METHODS: Five fresh calf spines and five human cadaveric spines (L2-L5) were used for nondestructive biomechanical flexibility testing. Maximum moments of 6.4 Nm were achieved in five increments of 1.6 Nm. The rotations of L3 with respect to L4 were measured in 5 cases: 1) intact; 2) following partial discectomy, including partial laminectomy and partial facetectomy; 3) partial discectomy with pedicle screw instrumentation; 4) total discectomy with pedicle screw instrumentation; and 5) pedicle screw instrumentation with interbody graft. Rotational angles were normalized to the intact case to determine the stabilizing effect during each testing case. Data were analyzed using analysis of variance to determine if significant differences existed between the calf spine results and the human cadaveric spine results. RESULTS: In both models, motion increased following discectomy, decreased with instrumentation, and increased with total discectomy. Placement of the interbody graft decreased motion during axial rotation, flexion, and extension but increased lateral bending motion. A two-way analysis of variance revealed no significant differences in the two models during flexion or extension (P > 0.05), but significant differences were discovered in axial rotation and lateral bending (P < 0.05). CONCLUSIONS: Significant differences were identified in flexibility testing between calf and human cadaveric specimens. The calf spine model overestimated the stabilizing effect of instrumentation during lateral bending and underestimated stability during axial rotation. The extrapolation of calf spine data to the in vivo case, especially during axial rotation and lateral bending, should carefully consider the variation between these two models.