Assessing Risk of Iatrogenic Peroneal Nerve Injury in All-Inside Lateral Meniscal Repair Between Standard Vs. Arthroscopic MRI.

BACKGROUND: Various studies have examined the risk of peroneal nerve injury with use of standard magnetic resonance imaging (MRI) of the knee. However, the position of the knee during standard MRI is different from that during an actual arthroscopic lateral meniscal repair. The purpose of the present study was to evaluate and compare the risk of peroneal nerve injury during simulated all-inside lateral meniscal repairs on the basis of MRI scans made with the knee in both positions. METHODS: With use of axial MRI scans made with the knee in the standard position (i.e., in 30° of flexion) and in the actual position used during arthroscopic lateral meniscal repair (i.e., in a figure-of-4 position), direct lines were drawn to simulate the passage of a straight all-inside meniscal repair device from the anteromedial and anterolateral portals to the medial and lateral borders of the popliteus tendon. The distance from the closest passage of each line to the peroneal nerve was measured. If a line touched or passed through the peroneal nerve, a risk of iatrogenic injury was noted and a new line was drawn from the same portal to the outer border of the peroneal nerve. The danger area was measured from the first line to the new line along the joint capsule. RESULTS: In 28 Thai patients, the shortest distances from each line to the peroneal nerve were significantly shorter on the MRI scans made with the knee in the standard position than on those made with the knee in the arthroscopic position (p < 0.05 for all). All danger areas on the MRI scans that were made with the knee in the arthroscopic position were included within the danger areas on the scans that were made with the knee in the standard position. CONCLUSIONS: Standard MRI scans of the knee can be used to determine the risk of peroneal nerve injury at the time of arthroscopic lateral meniscal repair, although the risks are slightly overestimated. LEVEL OF EVIDENCE: Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Using ChatGPT for Clinical Practice and Medical Education: Cross-Sectional Survey of Medical Students' and Physicians' Perceptions.

BACKGROUND: ChatGPT is a well-known large language model-based chatbot. It could be used in the medical field in many aspects. However, some physicians are still unfamiliar with ChatGPT and are concerned about its benefits and risks. OBJECTIVE: We aim to evaluate the perception of physicians and medical students toward using ChatGPT in the medical field. METHODS: A web-based questionnaire was sent to medical students, interns, residents, and attending staff with questions regarding their perception toward using ChatGPT in clinical practice and medical education. Participants were also asked to rate their perception of ChatGPT's generated response about knee osteoarthritis. RESULTS: Participants included 124 medical students, 46 interns, 37 residents, and 32 attending staff. After reading ChatGPT's response, 132 of the 239 (55.2%) participants had a positive rating about using ChatGPT for clinical practice. The proportion of positive answers was significantly lower in graduated physicians (48/115, 42%) compared with medical students (84/124, 68%; P<.001). Participants listed a lack of a patient-specific treatment plan, updated evidence, and a language barrier as ChatGPT's pitfalls. Regarding using ChatGPT for medical education, the proportion of positive responses was also significantly lower in graduate physicians (71/115, 62%) compared to medical students (103/124, 83.1%; P<.001). Participants were concerned that ChatGPT's response was too superficial, might lack scientific evidence, and might need expert verification. CONCLUSIONS: Medical students generally had a positive perception of using ChatGPT for guiding treatment and medical education, whereas graduated doctors were more cautious in this regard. Nonetheless, both medical students and graduated doctors positively perceived using ChatGPT for creating patient educational materials.

Cross-cultural adaptation and validation of the Thai version of the functional index for hand osteoarthritis (FIHOA).

BACKGROUND: The Functional Index for Hand Osteoarthritis (FIHOA) is a simple tool to assess functional impairment for hand OA patients. The purpose of this study was to translate the FIHOA into the Thai language, and validate it in Thai hand OA patients. METHODS: The FIHOA was translated into Thai (T-FIHOA) according to the principles of cross-cultural adaptation and administered to 102 hand OA patients recruited between September 2020 and July 2021 together with the modified Health Assessment Questionnaire (mHAQ), Disabilities of the Arm, Shoulder and Hand (DASH), and visual analogue scale (VAS) for hand pain. Spearman's correlation coefficient and intraclass correlation coefficient (ICC) were used to check the test-retest reliability of each item and the total scores in the translated questionnaire. The internal consistency reliability was evaluated using Cronbach's alpha. The external construct validity was assessed using correlations between the T-FIHOA, mHAQ, DASH and hand pain VAS. RESULTS: The T-FIHOA had a unidimensional structure. The ICC was > 0.9 and the Cronbach's alpha of 0.92 indicated excellent reliability and internal consistency, respectively. The external validity tests indicated moderate correlation with the hand pain VAS (r = 0.37, P <  0.01) and moderate to strong correlations with the mHAQ (r = 0.63, P <  0.01), and DASH score (r = 0.52, P <  0.01). The T-FIHOA had the highest effect size (ES) and standardized response mean (SRM) (- 0.37 and - 0.58 respectively) among all questionnaires except for the VAS when assessing changes between baseline and week 4. CONCLUSIONS: The T-FIHOA is a good and reliable assessment tool freely available for practitioners/researchers to evaluate functional impairment in Thai hand OA patients.

A Randomized Placebo-Controlled Trial of Efficacy and Safety: Drug-Free Gel Containing Ultra-Deformable Phospholipid Vesicles (TDT 064) in Osteoarthritic Knees.

BACKGROUND: There are a number of topical agents that are used for treatment of knee osteoarthritis. Drug-free gels, containing ultra-deformable phospholipid vesicles (TDT 064) are one such topical therapy, which have been stated to act as a bio lubricant. However, the evidence of TDT 064 in treatment of knee osteoarthritis is limited. Hence, the aim of this study was to evaluate the efficacy of pain control as a primary outcome and safety of TDT 064 compared with a topical placebo. METHODS: Sixty-four patients with primary osteoarthritis, with radiographic showing Kellgren and Lawrence classification grade II to III, were randomized into 2 groups. In the first group of 32 patients TDT 064 was used as topical agent, whilst in the second group of 32 patients a placebo identical in appearance was used instead. The verbal numerical rating scale (VNRS) was used for recording pain levels, Self-reported Knee Injury and Osteoarthritis Outcome Scores (KOOS) as well as amounts of rescue medication were also recorded. The data were recorded at the start of the study, and then at follow-up appointments of 14 days, 6 weeks, and 3 months. RESULTS: The mean VNRS for pain in both groups were significantly improved, when compared to the start of treatment (P < .0001); however, there were no differences between groups at any follow up visit. KOOS in all subscales were not significantly different between both groups at baseline and at the end of treatment. However, the average amount of NSAIDs in the TDT 064 group was 26.39 ± 22.11 tabs, which was significantly lower than the control group; which used an average 37.03 ± 19.22 tabs in 3 months (P = .047). CONCLUSIONS: There were no differences in the VNRS for pain and KOOS scores between the active and placebo groups. Although, TDT 064 could decrease usage of rescue medication the difference with use of a placebo was minimal. Further, larger trials would also be beneficial to demonstrate any differences between TDT 064 and a placebo. TRIAL REGISTRATION: TCTR, TCTR 20190302001. Registered 1 March, 2019: http://www.clinicaltrials.in.th.

Complications after intramedullary nail fixation of pathological versus non-pathological femoral shaft fractures: a retrospective cohort study in 233 patients.

BACKGROUND: Postoperative adverse events after intramedullary nailing have been reported in patients with metastatic pathological and non-pathological femoral fractures. Other consequences to be considered are readmission and reoperation. Few studies have compared the risks of postoperative adverse events, reoperation, and readmission after intramedullary nailing of pathological and non-pathological femur fractures. This study was designed to test the hypothesis that patients with pathological femoral fractures had more adverse events, readmission, and reoperation following surgical fixation than non-pathological femoral fractures. METHODS: This was a retrospective observational cohort study, conducted at an academic medical center in Thailand. The data from patients with femoral shaft fractures undergoing long intramedullary nailing, from June 1, 2006, to June 30, 2020, were included. Patients who had a pathological fracture from a primary bone tumor, metabolic bone disease, or inadequate/missing information were excluded. Patients with pathological fractures from metastatic bone disease were assigned to be the pathological group whereas those with traumatic fractures were assigned to be the non-pathological group. The primary outcome was the risk of inpatient adverse events as compared between the two groups. The secondary outcome was the risk of consequences after discharge as compared between the two groups. Outcomes were analyzed by using multivariate logistic regression analysis. RESULTS: The total number of patients was 48 in the pathological fracture group and 185 in the non-pathological group. There were significantly higher rates of surgical and medical adverse events in patients with pathological fractures compared to patients with non-pathological fractures. After adjusting for potential confounding factors in multivariate regression analysis, patients with pathological fractures had higher odds of both adverse surgical (adjusted OR 2.43, 95 % CI 1.15-5.13) and medical adverse events (adjusted OR 2.81, 95 % CI 1.13-7.03). CONCLUSIONS: Patients with metastatic pathological femoral shaft fractures undergoing intramedullary nailing were more likely to experience postoperative adverse events than patients with non-pathological fractures.

Soft tissue releasing and serial casting for management of flexion contracture after primary total knee arthroplasty in a patient with hemophilia.

INTRODUCTION AND IMPORTANCE: Flexion contracture following total knee arthroplasty (TKA) in patients with hemophilia is not uncommon, and this complication reduces knee range of motion and produces morbidity for the patient. This report states the success of treatment of flexion contracture after primary TKA in a patient with hemophilia; by open soft tissue contracture releasing and serial casting. CASE PRESENTATION: A 20-year-old-man presented with hemophilia type A. He had undergone TKA for treatment of secondary osteoarthritis, following chronic hemophilic arthropathy of his right knee. After surgery, the patient had progressive flexion contracture posture, until he had 45 degrees of knee flexion contracture at his 3 month follow up. The patient received open soft tissue releasing, then serial casting for 6 weeks. After this, the cast was removed and he continued with a home rehabilitation program. At 1 year follow, his knee flexion contraction contracture had improved up to 10 degrees. The patients function had recovered and he was satisfied with this treatment. CLINICAL DISCUSSION: The complications after TKA in patients with hemophilia are very challenging in there management; with flexion contracture after TKA being a common complication in patients with hemophilia. CONCLUSION: In severe flexion contracture following TKA, soft tissue releasing combined with serial casting is effective, and might be an option that is less invasive than revising all of the TKA components.

In vitro elution characteristics of gentamicin-impregnated Polymethylmethacrylate: premixed with a second powder vs. liquid Lyophilization.

BACKGROUND: Antibiotic-loaded bone cement, or antibiotic-impregnated polymethylmethacrylate (PMMA), were developed to prevent and treat bone and joint infections. Gentamicin is an antibiotic that is commonly used in combination with PMMA; however, gentamicin powder is hard to obtain in many countries. This study aimed to evaluate the elution characteristics of gentamicin-impregnated PMMA made with lyophilized liquid gentamicin, compared with PMMA; which is made from commercial gentamicin powder. METHODS: The experimental sample was divided into 2 groups: the gentamicin power group (PG-PMMA) and the lyophilized liquid gentamicin group (LG-PMMA). Ten cement spacers were prepared in each group. These were produced by mixing gentamicin powder, or lyophilized liquid gentamicin, with a powder polymer before adding the liquid monomer (2 g of gentamicin and 40 g of PMMA). The volume and surface area of the antibiotic-impregnated cement spacers were 50 cm3 and 110 cm2, respectively. Each spacer was immersed in phosphate-buffered saline, which was changed daily under sterile conditions. The solutions were collected to measure the level of gentamicin using the enzyme multiplied immunoassay technique (EMIT), at days 1, 2, 3, 4, 5, 6, 7, 14, 21, 28, 35 and 42. RESULTS: The collections from both groups had high concentrations of gentamicin on day 1 (113.63 ± 23.42 mg/dL in LG-PMMA and 61.7 ±8.37 mg/dL in PG-PMMA), but experienced a continuous decrease over time. The PMMA spacers from both groups could release gentamicin for up to 6 weeks (3.28 ± 1.17 mg/dL in LG-PMMA and 1.21 ± 0.28 mg/dL in PG-PMMA). However, there were significantly higher levels of gentamicin concentrations in the LG-PMMA group compared to the PG-PMMA group at all time points (P< 0.05). CONCLUSION: Gentamicin-impregnated PMMA made with lyophilized liquid gentamicin had approximately a two times higher rate of antibiotic elution in preliminary in vitro studies, as compared with PMMA made with premixed gentamicin powder.

Balanced Suspension versus Pillow on Preoperative Pain for Proximal Femur Fractures: A Randomized Controlled Trial.

INTRODUCTION: To evaluate the efficacy of a balanced suspension system, using the Thomas splint, with Pearson attachment, compared with a pillow for preoperative pain in patients with proximal femoral fractures. MATERIALS AND METHODS: Sixty patients with proximal femur fractures were randomized into two groups: a balanced suspension group and a pillow group. In the first group, a balanced suspension was applied after length adjustment, to match the patient's leg and thigh. In the pillow group, a pillow was placed below the patient's leg, to position the patient's hip in a semiflexion and external rotation position. Preoperative pain severity, by using a verbal numerical rating scale (VNRS), the amount of morphine consumed, and complication were recorded. RESULTS: There were no differences in patient characteristics between the groups. The mean VNRS for pain was not statistically different between the groups, from the start of the study up to 48 hours. The mean of morphine consumption was not different between the groups at the start of the study, on day 1, and on day 2 (p=0.25, 0.89, and 0.053, respectively). CONCLUSIONS: A balanced suspension did not improve patient outcome to the same level as other tractions in previous studies. Hence, other methods for reducing pain, while waiting for definite operations, should be focused on. The clinical trial is registered with TCTR20150514002.

Coronal Alignment Correction and Maintenance of Tibial Slope in Opening-Wedge Valgus High Tibial Osteotomy Using a 4-Reference Kirschner Wire Technique: A Cadaveric Study.

BACKGROUND: Opening-wedge valgus high tibial osteotomy (OWHTO) is a common surgical procedure used to treat symptomatic varus femorotibial malalignment in adults. Several intraoperative methods are available to determine the correct correction alignment, but achieving the desired alignment correction is difficult. PURPOSE/HYPOTHESIS: The aim of this study was to assess a 4-reference K-wire technique that is relatively easy to apply and can reliably assess actual alignment correction during surgery after determination of the desired corrective angle. We hypothesized that this technique would accurately determine the coronal correction and properly maintain the tibial slope intraoperatively during OWHTO. STUDY DESIGN: Descriptive laboratory study. METHODS: This study was conducted using 12 fresh-frozen cadavers; 12 randomly chosen knees were corrected 5° and 12 knees were corrected 10° by use of 2 coronal and 2 sagittal K-wires. The first and second coronal K-wires were drilled at 4 cm and 1 to 2 cm below the medial joint line toward the tibiofibular joint, respectively. The angles of these 2 coronal K-wires were measured before and after the gap was opened via a modified goniometer. The difference in the angle formed by these 2 coronal K-wires from before to after opening of the gap was the alignment correction angle. In addition, 2 sagittal K-wires were drilled parallel to each other before the gap opening above and below the osteotomy site. Ensuring that these 2 sagittal K-wires remained parallel after the gap opening confirmed that the tibial slope had been maintained. The paired t test was used to compare the desired alignment corrections and the different angles measured between the pre- and postoperative radiographic alignments. RESULTS: The mean ± SD differences in angles between the pre- and postoperative alignments of the 5° and 10° corrections were 5.04° ± 0.68° and 10.03° ± 0.68°, respectively, indicating no statistically significant differences between pre- and postoperative alignment in both groups. As well, no significant difference was noted between the pre- and postoperative medial tibial slope (P = .54). CONCLUSION: The coronal alignment correction and maintenance of the tibial slope using the 4-reference K-wire technique was found to be highly accurate and reliable. CLINICAL RELEVANCE: Achieving the correct angle in OWHTO is difficult, and the 4-reference K-wire technique provides an easier and more reliable way to obtain the correct angle. This technique can be used in most hospital settings, with no need for expensive equipment.

Physical ergonomic risk factors of carpal tunnel syndrome among rubber tappers.

This study evaluated physical ergonomic risk factors associated with carpal tunnel syndrome (CTS) among rubber tappers in Thailand. The Boston Carpal Tunnel Syndrome Questionnaire and Phalen's test and Tinel's sign were used to identify 133 cases with CTS and 401 non-CTS controls. Video recordings and Rapid Upper Limb Assessment used to evaluate the level of ergonomic risk in right and left hand postures. Significant physical ergonomic risk factors of CTS were higher number of trees tapped at or below knee level and collecting latex. Among right-handed tappers, tapping at higher than chest level involved significantly higher proportion of right wrist flexion and/or extension, and left wrist radial and/or ulnar deviation and twist than tapping at a lower level.

Patient Position Is Related to the Risk of Neurovascular Injury in Clavicular Plating: A Cadaveric Study.

BACKGROUND: Fixation of clavicle shaft fractures with a plate and screws can endanger the neurovascular structures if proper care is not taken. Although prior studies have looked at the risk of clavicular plates and screws (for example, length and positions) to vulnerable neurovascular structures (such as the subclavian vein, subclavian artery, and brachial plexus) in the supine position, no studies to our knowledge have compared these distances in the beach chair position. QUESTIONS/PURPOSES: (1) In superior and anteroinferior plating of midclavicle fractures, which screw tips in a typical clavicular plating approach place the neurovascular structures at risk of injury? (2) How does patient positioning (supine or beach chair) affect the distance between the screws and the neurovascular structures? METHODS: The clavicles of 15 fresh-frozen cadavers were dissected. A hypothetical fracture line was marked at the midpoint of each clavicle. A precontoured six-hole 3.5-mm reconstruction locking compression plate was applied to the superior surface of the clavicle by using the fracture line to position the center of the plate. The direction of the drill bits and screws through screw holes that offer the greater risk of injury to the neurovascular structures were identified, and were defined as the risky screw holes, and the distances from the screw tips to the neurovascular structures were measured according to a standard protocol with a Vernier caliper in both supine and beach chair positions. Anteroinferior plating was also assessed following the same steps. The different distances from the screw tips to the neurovascular structures in the supine position were compared with the distances in the beach chair position using an unpaired t-test. RESULTS: The risky screw holes were the first medial and second medial screw holes. The relative distance ratios compared with the entire clavicular length for the distances from the sternoclavicular joint to the first medial and second medial screw holes were 0.46 and 0.36 in superior plating and 0.47 and 0.37 in anteroinferior plating, respectively. The riskiest screw hole for both superior and anteroinferior plates was the second medial screw hole in both the supine and beach chair positions (supine superior plating: 8.2 mm ± 3.1 mm [minimum: 1.1 mm]; beach chair anteroinferior plating: 7.6 mm ± 4.2 mm [minimum: 1.1 mm]). Patient positioning affected the distances between the riskiest screw tip and the nearest neurovascular structures, whereas in superior plating, changing from the supine position to the beach chair position increased this distance by 1.4 mm (95% CI -2.8 to -0.1; supine 8.2 ± 3.1 mm, beach chair 9.6 ± 2.1 mm; p = 0.037); by contrast, in anteroinferior plating, changing from the beach chair position to the supine position increased this distance by 5.4 mm (95% CI 3.6 to 7.4; beach chair 7.6 ± 4.2 mm, supine 13.0 ± 3.2 mm; p < 0.001). CONCLUSIONS: The second medial screw hole places the neurovascular structures at the most risk, particularly with superior plating in the supine position and anteroinferior plating in the beach chair position. CLINICAL RELEVANCE: The surgeon should be careful while making the first medial and second medial screw holes. Superior plating is safer to perform in the beach chair position, while anteroinferior plating is more safely performed in the supine position.

Intramedullary sealing with a bone plug in total knee arthroplasty to reduce blood loss: a meta-analysis of randomized controlled trials.

BACKGROUND: An intramedullary guide is an instrument that surgeons use to align the distal femoral cut. The opening may become a channel that drains intramedullary blood to the knee joint after surgery if left open during surgery. The authors aimed to evaluate the effects of an intramedullary bone plug with respect to postoperative blood loss from a meta-analysis. METHODS: The authors performed a systematic review and meta-analysis to compare a sealed opening using an intramedullary bone plug with no bone plug. PubMed, Ovid, Embase, and Cochrane Library were used to identify all publications before May 2018. All of the included studies were evaluated for bias and heterogeneity. RESULTS: Six hundred and thirty-six patients from four randomized controlled trials were included in this meta-analysis. The pooled results demonstrated that patients with intramedullary plug had lower rates of blood transfusion and lower level of reduced postoperative hemoglobin than patients in whom the intramedullary canal was not plugged. DISCUSSION: This meta-analysis demonstrated the benefit of intramedullary sealing with a bone plug in total knee arthroplasty with respect to decreased postoperative blood loss.

Proximity of the Coracoid Process to the Neurovascular Structures in Various Patient and Shoulder Positions: A Cadaveric Study.

PURPOSE: To examine and compare the distances from the anteromedial aspects of the coracoid base and the coracoid tip to the neurovascular structures in various patient positions. METHODS: The experiment was conducted in 15 fresh-frozen cadavers. We dissected 15 right and 15 left shoulders to measure the distances from the anteromedial aspects of the coracoid base and the coracoid tip to the lateral border of the neurovascular structures in the horizontal, vertical, and closest planes. The measurements were performed with the cadavers in the supine, lateral decubitus, and beach-chair positions. With cadavers in the beach-chair position, we evaluated 5 arm postures (arm at side, 45° of abduction, 90° of abduction, 45° of forward flexion, and 90° of forward flexion). RESULTS: The shortest distance from the coracoid base to the neurovascular structures was found in the beach-chair position with arm at side in the horizontal plane (27.4 ± 4.9 mm) and 90° of abduction in the vertical (21.8 ± 4.2 mm) and closest (19.5 ± 4.2 mm) planes. The distances in each plane were statistically significant compared with the supine and lateral decubitus positions (P < .005). Between the coracoid tip and the neurovascular structures, the shortest distance was found in the beach-chair position with 90° of abduction, with 29.3 ± 7.7 mm, 20.8 ± 4.9 mm, and 18.5 ± 5.1 mm in the horizontal, vertical, and closest planes, respectively. The distances were statistically significant in all planes compared with the supine and lateral decubitus positions (P < .005). CONCLUSIONS: Shoulder surgery in the area of the coracoid process is safe, especially with the patient in the supine position. The distance from the coracoid process to the neurovascular structures was closest in the beach-chair position with 90° of arm abduction. CLINICAL RELEVANCE: This study determined the distances between the coracoid process and the neurovascular structures during surgery around the coracoid process.

Biomechanical Study of Posterior Pelvic Fixations in Vertically Unstable Sacral Fractures: An Alternative to Triangular Osteosynthesis.

STUDY DESIGN: Biomechanical study. PURPOSE: To investigate the relative stiffness of a new posterior pelvic fixation for unstable vertical fractures of the sacrum. OVERVIEW OF LITERATURE: The reported operative fixation techniques for vertical sacral fractures include iliosacral screw, sacral bar fixations, transiliac plating, and local plate osteosynthesis. Clinical as well as biomechanical studies have demonstrated that these conventional techniques are insufficient to stabilize the vertically unstable sacral fractures. METHODS: To simulate a vertically unstable fractured sacrum, 12 synthetic pelvic models were prepared. In each model, a 5-mm gap was created through the left transforaminal zone (Denis zone II). The pubic symphysis was completely separated and then stabilized using a 3.5-mm reconstruction plate. Four each of the unstable pelvic models were then fixed with two iliosacral screws, a tension band plate, or a transiliac fixation plus one iliosacral screw. The left hemipelvis of these specimens was docked to a rigid base plate and loaded on an S1 endplate by using the Zwick Roell z010 material testing machine. Then, the vertical displacement and coronal tilt of the right hemipelves and the applied force were measured. RESULTS: The transiliac fixation plus one iliosacral screw constructions could withstand a force at 5 mm of vertical displacement greater than the two iliosacral screw constructions (p=0.012) and the tension band plate constructions (p=0.003). The tension band plate constructions could withstand a force at 5° of coronal tilt less than the two iliosacral screw constructions (p=0.027) and the transiliac fixation plus one iliosacral screw constructions (p=0.049). CONCLUSIONS: This study proposes the use of transiliac fixation in addition to an iliosacral screw to stabilize vertically unstable sacral fractures. Our biomechanical data demonstrated the superiority of adding transiliac fixation to withstand vertical displacement forces.

Reliability and Accuracy of Palpable Anterior Neck Landmarks for the Identification of Cervical Spinal Levels.

STUDY DESIGN: A descriptive experimental study. PURPOSE: The purpose of this study was to describe the reliability and accuracy of palpable anterior neck landmarks (angle of the mandible, hyoid bone, thyroid cartilage, and cricoid cartilage) for the identification of cervical spinal levels in a slight neck-extended position as in anterior approach cervical spinal surgery. OVERVIEW OF LITERATURE: Standard, palpable anatomical landmarks for the identification of cervical spinal levels were described by Hoppenfeld using the midline palpable anterior structures (angle of the mandible [C2 body], hyoid bone [C3 body], thyroid cartilage [C4-C5 disc], cricoid cartilage [C6 body], and carotid tubercle [C6 body]) to determine the approximate level for skin incisions. However, in clinical practice, patients are positioned with a slight neck extension to achieve cervical lordosis. This positioning (neck extension) may result in changes in the locations of anatomical landmarks compared with those reported in previous studies. METHODS: This experimental study was conducted on 96 volunteers. Each volunteer was palpated for locating four anatomical landmarks three times by three different orthopedic surgeons. We collected data from the level of the vertebral body or the vertebral disc matching the surface anatomical landmarks from the vertical reference line. RESULTS: Accuracy of the angle of the mandible located at the C2 vertebral body was 95.5%, the hyoid bone located at the C2/3 intervertebral disc was 51.7%, the thyroid cartilage located at the C4 vertebral body was 42%, and the cricoid cartilage located at the C5/6 intervertebral disc was 43.4%. CONCLUSIONS: With the neck in a slightly extended position to achieve cervical lordosis, the angle of the mandible, the hyoid bone, the thyroid cartilage, and the cricoid cartilage were most often located at the C2 body, the C2/3 disc, the C4 body, and the C5/6 disc, respectively. The angle of the mandible and the hyoid bone are highly reliable surface anatomical landmarks for the identification of cervical spinal levels than the thyroid cartilage and the cricoid cartilage.

Occupational Tasks Influencing Lung Function and Respiratory Symptoms Among Charcoal-Production Workers: A Time-Series Study.

BACKGROUND: Tasks involved in traditional charcoal production expose workers to various levels of charcoal dust and wood smoke. This study aimed to identify specific tasks influencing lung function and respiratory symptoms. METHODS: Interviews, direct observation, and task/symptom checklists were used to collect data from 50 charcoal-production workers on 3 nonwork days followed by 11 workdays. The peak expiratory flow rate (PEFR) was measured four times per day. RESULTS: The PEFR was reduced and the prevalence of respiratory symptoms increased over the first 6-7 workdays. The PEFR increased until evening on nonwork days but not on workdays. Loading the kiln and collecting charcoal from within the kiln markedly reduced the PEFR and increased the odds of respiratory symptoms. CONCLUSION: Tasks involving entry into the kiln were strongly associated with a short-term drop in the PEFR and the occurrence of respiratory symptoms, suggesting a need for the use of protective equipment and/or the operation of an effective kiln ventilation system.

The Effect of Phototherapy on Cancer Predisposition Genes of Diabetic and Normal Human Skin Fibroblasts.

The purpose of this study was to investigate whether LED light at different wavelengths affects the expression profile of 143 cancer predisposition genes in both diabetic and normal human fibroblasts. In this study, both diabetic and normal fibroblast cell lines were cultured and irradiated with red (635 nm), green (520 nm), and blue (465 nm) LED light for 10 minutes at 0.67 J/cm2 each. After that, mRNA from all cell lines was extracted for microarray analysis. We found that green light activates EPHB2, KIT, ANTXR2, ESCO2, MSR1, EXT1, TSC1, KIT, NF1, BUB1B, FANCD2, EPCAM, FANCD2, NF, DIS3L2, and RET in normal fibroblast cells, while blue and red light can upregulate RUNX1, PDGFRA, EHBP1, GPC3, AXIN2, KDR, GLMN, MSMB, EPHB2, MSR1, KIT, FANCD2, BMPR1A, BUB1B, PDE11A, and RET. Therefore, genetic screening before phototherapy treatment may be required.

Effects of Titanium Surface Microtopography and Simvastatin on Growth and Osteogenic Differentiation of Human Mesenchymal Stem Cells in Estrogen-Deprived Cell Culture.

PURPOSE: This study aimed to investigate the effects of titanium surface topography and simvastatin on growth and osteogenic differentiation of human bone marrow stromal cells (hBMSCs) in estrogen-deprived (ED) cell culture. MATERIALS AND METHODS: Human BMSCs were seeded on cell culture plates, smooth-surface titanium (Ti) disks, and sandblasted with large grits and acid etched (SLA)-surface Ti disks; and subsequently cultured in regular (fetal bovine serum [FBS]), ED, and ED-with 100 nM simvastatin (ED-SIM) culture media for 14 to 21 days. Live/dead cell staining, scanning electron microscope examination, and cell viability assay were performed to determine cell attachment, morphology, and growth. Expression levels of osteoblast-associated genes, Runx2 and bone sialoprotein and levels of alkaline phosphatase (ALP) activity, calcium content, and osteocalcin in culture media were measured to determine osteoblastic differentiation. Expression levels of bone morphogenetic protein-2 (BMP-2) were investigated to examine stimulating effects of simvastatin (n = 4 to 5, mean ± SD). In vitro mineralization was verified by calcein staining. RESULTS: Human BMSCs exhibited different attachment and shapes on smooth and SLA titanium surfaces. Estrogen-deprived cell culture decreased cell attachment and growth, particularly on the SLA titanium surface, but cells were able to grow to reach confluence on day 21 in the ED-osteogenic (OS) culture medium. Promoting effects of the SLA titanium surface in ED-OS were significantly decreased. Simvastatin significantly increased osteogenic differentiation of human BMSCs on the SLA titanium surface in the ED-OS medium, and the promoting effects of simvastatin corresponded with the increasing of BMP-2 gene expression on the SLA titanium surface in ED-OS-SIM culture medium. CONCLUSION: The ED cell culture model provided a well-defined platform for investigating the effects of hormones and growth factors on cells and titanium surface interaction. Titanium, the SLA surface, and simvastatin synergistically promoted osteoblastic differentiation of hBMSCs in ED condition and might be useful to promote osteointegration in osteoporotic bone.

The Significance of the Trömner Sign in Cervical Spondylotic Myelopathy Patient.

STUDY DESIGN: This study is a diagnostic analysis. OBJECTIVE: To investigate the diagnostic accuracy of Trömner sign in cervical spondylotic myelopathy (CSM), and how its presence correlates with the severity of myelopathy. SUMMARY OF BACKGROUND DATA: A clinical presentation of myelopathy corresponding with image findings is a current standard to diagnose CSM. Trömner sign is an alternative of well-known Hoffmann sign to detect CSM. Little is known about its diagnostic accuracy and how its presence correlates with the severity of CSM. MATERIALS AND METHODS: Consecutive patients with clinical diagnosis of CSM and other cervical spondylosis-related problems were enrolled in either CSM group, cervical spondylotic radiculopathy group, or axial pain group. Normal volunteers and patients without spine-related issues were used as a control. All participants were examined for the presence of myelopathic signs. Magnetic resonance imaging studies of all participants were reviewed by a radiologist. RESULTS: There were 85 participants included in the study. Diagnostic sensitivity was 76%, 94%, 76%, and 36% for Hoffmann sign, Trömner sign, inverted radial reflex, and Babinski sign, respectively. Trömner sign had relatively high sensitivity (95%) despite of mild degree of myelopathy. Negative predictive value was 60%, 85%, 59%, and 38% for Hoffmann sign, Trömner sign, inverted radial reflex, and Babinski sign, respectively. There were 63%-71% of patients in either axial pain group or cervical spondylotic radiculopathy group had positive Trömner sign. Most of CSM patients with cord signal changed had positive myelopathic sign. Regarding CSM patient without cord signal change, most of tests were negative except Trömner sign. CONCLUSIONS: High sensitivity (94%) and relatively high negative predictive value (85%) for Trömner sign indicate the usefulness of Trömner sign in ruling out CSM. High incidence of positive Trömner sign in presymptomatic cervical cord compression patients suggests Trömner sign could have a useful role in early detection of presymptomatic patients.

Prevalence of congenital limb defects: Data from birth defects registries in three provinces in Southern Thailand.

This is the first population-based study in Thailand on the prevalence of congenital limb defects (CLD). Data were obtained from recently established birth defects registries in three southern Thailand provinces during 2009-2013. Entries in the birth defects registries included live births, stillbirths after 24 weeks gestational age, and terminations of pregnancy following a prenatal diagnosis of fetal anomaly. The total of 186 393 births recorded included 424 CLD cases, giving an average prevalence of 2.27 per 1000 births (95% CI, 2.05-2.49). The most common CLD was talipes equinovarus (44.1%), followed by polydactyly (13.9%) and syndactyly (9.4%). The prevalence significantly increased with maternal age from 1.81 in mothers aged <30 years to 2.75 in mothers 30 to < 35 years, and to 2.94 in mothers ≥35 years (P = 0.004). Overall 9.4% of the CLDs were syndromic CLD, again with significantly greater percentages in pregnant women aged ≥35 years than the non-syndromic CLD (32.5% vs 17.5% respectively, P = 0.03). In conclusion, the overall prevalence of CLD in the 3 southern Thailand provinces examined was 2.27 per 1000 births, and syndromic CLD was significantly higher in pregnant women aged ≥35 years than younger pregnant women.