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Various syndesmotic fixation methods in ankle injury are recommended; however, a lack of biomechanical information persists regarding the stiffness of the fixation methods. The current study thus aimed to assess biomechanical cadaveric validation and perform a finite element analysis of syndesmotic fixation comparing endobutton vs. screw after syndesmotic injury with an ankle fracture.Five pairs of ankles of fresh cadavers were used for the validity test for Anterior Inferior Tibiofibular Ligament (AITFL), Posterior Inferior Tibiofibular Ligament (PITFL), and Interosseous ligament biomechanics properties. Four finite element models (FEM) were created: an intact model, a fracture model with/without syndesmotic injury, an endobutton fixation model, and a syndesmotic screw fixation model. Each FEM was tested vis-à-vis external rotation force, anteroposterior translation force, and compression force until model failure. The primary outcomes were stiffness and force until failure.The respective anteroposterior translation force for the stiffness of the intact model, the screw fixation model, and the endobutton fixation was 8.14, 9.15, and 8.17 N/mm. The respective external rotation force for the stiffness of intact, screw fixation, and endobutton model was 0.927,0.949, and 0.940 Nm/degree. The respective stress under compression force in the intact, screw fixation, and endobutton model was 39.94,25.59, and 37.30 MPa.Both screw and endobutton fixation models provided more translation, compression, and rotation stability than normal syndesmosis, but the screw model provided greater translation and compression force stability than the endobutton model. There was no difference in rotational stability between the two models. We thus recommend the same rehabilitation protocol for both fixation methods; however, vigorous translation and compression should be avoided when using endobutton fixation.

Finite element analysis (FEA) is increasingly applied to medicine because it could increase accuracy and rapid outcomes. However, there is a lack of the method to determine Young’s modulus and Poisson’s ratio for fresh femoral bone and the mathematical principle’s optimization for calculating nonuniform configuration. This study aimed to investigate the surrogate model for the optimization method to determine Young’s modulus and Poisson’s ratio of the fresh femoral bone. Young’s modulus and Poisson’s ratio obtained 20 ranked pairs by the Latin hypercube sampling method. The values ​​were calculated in the finite element for root mean square error (RMSE) and were then used for solutions by a quadratic function, radial basis function (RBF), and Kriging (KG). The lowest RMSE value was 0.1518 for the RBF method, with the young’s modulus at 304.4756 and the Poisson’s ratio at 0.3334. The current study identified the RBF technique to determine the properties of the femoral bone. Moreover, the RBF procedure might apply to other long bones because of the comparable nonuniform configuration.

BACKGROUND: The L2 nerve root is considered part of the lumbar plexus that innervates the iliopsoas (IP) and quadricep muscles (Qd). Total en bloc spondylectomy (TES) at the L2 vertebra requires bilateral nerve root transection to facilitate surgical dissection and vertebral body removal. Information regarding neurological function recovery of the IP and Qd in patients with muscle weakness before TES is lacking. We aimed to report the neurological recovery of IP and Qd after TES involving the L2 vertebra in preoperative lower extremity weakness in spinal tumor patients. METHODS: We prospectively recorded all L2-involved spinal tumor patients undergoing TES between January 2018 and November 2020. As a primary outcome, we recorded the Manual Muscle Testing (MMT) grade of the IP and Qd preoperatively, immediately postoperatively, and at follow-up. Secondary outcomes included the Frankel neurological status, sensation impairment, and the Eastern Cooperative Oncology Group score. RESULTS: From 8 TES-involving L2 patients, 6 (4 males) met the inclusion criteria. One patient had first-grade deterioration of the Qd MMT immediately postoperatively. All patients could ambulate independently 6 months after surgery. Five patients required follow-up for more than 1 year and could walk without any gait aids. All patients had persistent anterior groin and bilateral thigh numbness until the final follow-up. CONCLUSION: Neurological recovery of the IP and Qd muscles as measured by MMT can occur within 6 months of bilateral L2 nerve root transection. Bilateral L2 nerve root sacrifice can have acceptable neurological outcomes and recovery, even in patients with preoperative IP and Qd weakness. LEVEL OF EVIDENCE: 4.

PurposeThere is little information available regarding the cage diameter that can provide the most rigid construct reconstruction after total en bloc spondylectomy (TES). The aim of this study was thus to determine the most appropriate titanium mesh cage diameter for reconstruction after spondylectomy.MethodsA finite element model of the single level lumbar TES was created. Six models of titanium mesh cage with diameters of 1/3, 1/2, 2/3, 3/4, 4/5 of the caudad adjacent vertebra, and 1/1 of the cephalad vertebra were tested for construct stiffness. The peak von Mises stress (MPa) at the failure point and the site of failure were measured as outcomes. A cadaveric validation study also conducted to validate the finite element model.ResultsFor axial loading, the maximum stress points were at the titanium mesh cage, with maximum stress of 44,598 MPa, 23,505 MPa, 23,778 MPa, and 16,598 MPa, 10,172 MPa, 10,805 MPa in the 1/3, 1/2, 2/3, 3/4, 4/5, and 1/1 diameter model, respectively. For torsional load, the maximum stress point in each of the cages was identified at the rod area of the spondylectomy site, with maximum stress of 390.9 MPa (failed at 4459 cycles), 141.35 MPa, 70.098 MPa, and 88.972 MPa, 42.249 MPa, 15.827 MPa, respectively. A cadaveric validation study results were coincided with the finite element model results.ConclusionThe most appropriate mesh cage diameter for reconstruction is 1/1 the diameter of the lower endplate of the adjacent cephalad vertebra, due to its ability to withstand both axial and torsional stress. According to the difficulty of large size cage insertion, a cage diameter of more than half of the upper endplate of the caudad vertebrae is acceptable in term of withstand stress. A cage diameter of 1/3 is unacceptable for reconstruction after total en bloc spondylectomy.

There have been no studies comparing the outcomes of nonvascularized autograft (NA) and allograft after resection of primary bone tumors. This study compares the clinical, functional outcomes of NA and allograft reconstruction and analyzes the risk factors for failure after these procedures. A retrospective study of patients with primary bone tumors of the extremities who underwent NA (n = 50) and allograft reconstruction (n = 47). The minimum follow up time was 24 months. The mean time to union for the NA and allograft group was 9.8 ± 2.9 months and 11.5 ± 2.8 months, respectively (p = 0.002). Reconstruction failure in the NA and allograft group was 19 (38%) and 26 (55.3%), respectively. Nonunion (30%) was the most common complication found in the NA group, while structural failure (29.8%) was the most common in the allograft group. There was no significant difference in functional outcome in terms of the mean Musculoskeletal Tumor Society score between the NA and allograft groups (23.5 ± 2.8 and 23.9 ± 2.1, respectively, p = 0.42). Age, sex, tumor location, graft length, method of reconstruction did not significantly influence failure of reconstruction. Chemotherapy was the only significant risk factor affecting outcomes (HR = 3.49, 95% CI = 1.59–7.63, p = 0.002). In the subgroup analysis, the use of chemotherapy affected graft-host nonunion (p p = 0.02). Both NA and allograft reconstruction methods provide acceptable clinical and functional outcomes. Chemotherapy is a risk factor for failure of both reconstructions, particularly graft-host nonunion and structural failure.

Biological reconstruction is widely used to reconstruct bone defects after resection of bone tumors in the extremities. This study aimed to identify risk factors for failure and to compare outcomes of the allograft, nonvascularized autograft, and recycled frozen autograft reconstruction after resection of primary malignant bone tumors in the extremities. A retrospective study was performed at a single center between January 1994 and December 2017. Ninety patients with primary malignant bone tumors of the extremities were treated with tumor resection and reconstruction using one of three bone graft methods: nonvascularized autograft (n = 27), allograft (n = 34), and recycled frozen autograft (n = 29). The median time for follow-up was 59.2 months (range 24–240.6 months). Overall failure of biological reconstruction occurred in 53 of 90 patients (58.9%). The allograft group had the highest complication rates (n = 21, 61.8%), followed by the recycled frozen autograft (n = 17, 58.6%) and nonvascularized autograft (n = 15, 55. 6%) groups. There was no statistically significant difference among these three groups (p = 0.89). The mean MSTS score was 22.6 ± 3.4 in the nonvascularized autograft group, 23.4 ± 2.6 in the allograft group, and 24.1 ± 3.3 in the recycled frozen autograft group. There was no significant difference among the groups (p = 0.24). After bivariate and multivariable analyses, patient age, sex, tumor location, graft length, methods, and type of reconstruction had no effects on the failure of biological reconstruction. Biological reconstruction using allograft, nonvascularized autograft, and recycled frozen autograft provide favorable functional outcomes despite high complication rates. This comparative study found no significant difference in functional outcomes or complication rates among the different types of reconstruction.

Background In recent years, pedicle screw (PS) fixation has often been used to stabilize the spine and correct deformities, yielding good clinical results. On the other hand, PS fixation is known to show problems such as instrumentation failure. However, few biomechanical studies have described causes of instrumentation failure. In this study, causes of instrumentation failure in lumbar PS fixation were investigated from the perspective of load sharing by measuring both strains generated in the rod and intradiscal pressure.Methods Four human cadaveric multi-segmental lumbar vertebrae (L2-L5) were used to prepare a control model and a PS fixation model. Next, axial compression tests were performed on each model using a universal material testing machine, and the strains generated in the rods and the intradiscal pressures were measured from strain gauges attached to the rods and a pressure sensor installed between L3-L4.Results Combined compressive and bending stresses were found to be generated in the rod, with bending stress around 10 times higher than compressive stress, and with vast differences in the levels of stress generated between right and left rods. Moreover, the stress shielding by PS fixation was small, and intervertebral discs were still subjected to a large load. Conclusion Preventing instrumentation failure in lumbar spine PS fixation, it seems necessary to strengthen the durability of the rod against bending stress and to ensure the stability of the anterior stabilizing element of the spine.

Background The Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) was developed to resolve problems associated with the original evaluation of cervical myelopathic patients. The aim of this study was to translate the JOACMEQ into Thai as per international recommendations, and to test its reliability and validity in the Thai context Methods The JOACMEQ was translated into Thai, using international guidelines. Cervical myelopathy patients (n = 70; 31 males) were asked to complete the Thai version JOACMEQ twice (4 weeks apart). Test-retest reliability was analyzed using the intra-class correlation coefficient (ICC). Internal consistencies were analyzed using Cronbach's alpha, while the construct validity was compared with the Thai version modified SF-36; using the Spearman's rank correlation coefficient. Results The Thai JOACMEQ produced good reliability (i.e., the ICC was >0.9 in 2 parameters and >0.8 in one). Overall the Cronbach's α for the 24 questions showed very high internal consistency (Cronbach's α > 0.8) and almost all Cronbach's α showed satisfactory internal consistency except for bladder function. The Spearman's rank correlation for all the JOACMEQ parameters had a positive correlation with all Thai SF 36 subscales, especially the quality of life parameter, which showed a strong correlation with all SF-36 subscales. Conclusion The Thai version of the JOACMEQ had satisfactory internal consistency and test-retest reliability: it also had good construct validity. It can therefore be used as a reliable tool for assessing quality of life for cervical myelopathy patients in Thailand.

Background: The aim of this study was to evaluate survival of metastatic bone disease of an upper extremity, and to identify the prognostic factors that influence survival. Methods: Patients with metastatic bone disease of an upper extremity between 2008 and 2015 were reviewed from the database of a tertiary university hospital. Results: Of 102 patients, 48 males and 54 females with a median age of 61 (range, 28–82 years), the humerus (64.7%), clavicle (13.7%), and scapula (12.7%) were the common sites for bone metastasis of an upper extremity. Fifty-nine (57.8%) presented with pathologic fracture. No history of cancer was found in 76.5% of patients. The mean onset of metastatic bone disease after the first diagnosis of primary cancer was 4.74 ± 14.07 months (range, 0–84 months). Lung (31.4%) was the most common primary cancer followed by liver (14.7%), breast (12.7%), thyroid (7.8%), and renal (3.9%). Eighty-two cases (80.39%) died from the disease such that the median survival was 4.08 months (95% CI 2.57–6.17). The significant risk factors were the type of primary tumor (P

This is the protocol for a review and there is no abstract. The objectives are as follows: To compare the efficacy and safety of different chemotherapy regimens in children and young adults with high‐grade osteosarcoma when compared to other chemotherapeutic regimens.

Malpositioning of cervical screws risks neurovascular injury. A cervical screw fixation system can provide proper rigidity, alignment correction, and high rates of fusion afforded by high pullout biomechanical strength. The objective is to assess the dimensions and axis of the C3-C7 cervical pedicles. A 1-mm slice thickness computed tomography (CT) scan of the cervical spine of 30 patients (15 males, 15 females) were analyzed and reconstructed in three-dimensions using Mimics(®) 10.01 software. We measured pedicle axis length (PAL), pedicle and lateral mass length (PL-LM), pedicle length (PL), outer pedicle width (OPW), and pedicle transverse angle (PTA) from the axial image and outer pedicle height (OPH) and pedicle sagittal angle (PSA) from the sagittal image. The OPH and OPW at all subaxial cervical spines were suitable for insertion of 3.5 mm cervical pedicle screws. PSA was directed cranially at C3 to C5 (13.84, 7.09, and 2.71) and directed caudally at C6 and C7 (-4.55, -6.94). PTA was greatest at C5 and smallest at C7. The respective difference between the left and right side for nearly all parameters was not statistically significant (except for C6 PL and C7 OPH). Females had a significantly smaller OPH and OPW than males at nearly all levels. The PTA was not significantly different between the sexes. Cervical pedicle screw fixation in the Thai population can be safely performed and guidelines for insertion at each vertebra documented. Appropriate preoperative planning is necessary to achieve safe and accurate placement of the screws.

Background The Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ) was developed by the Japanese Orthopedic Association (JOA) for assessment of lower back pain and lumbar spinal disease. We aimed to translate the JOABPEQ into Thai and test its reliability and validity in the Thai context. Methods The original JOABPEQ was translated into Thai in accordance with international recommendations. Then 180 lumbar spinal disease patients (mean age 58.58 ± 11.97, 68.3% female) were asked to complete the Thai version of the JOABPEQ twice at 2-week intervals. Test-retest reliability was analyzed using the intra-class correlation coefficient (ICC). Internal consistencies were analyzed using Cronbach's alpha, while the construct validity was compared with the Thai version of the modified SF-36, and tested using the Spearman's rank correlation coefficient. Results The Thai JOABPEQ showed satisfactory test-retest reliability in all parameters (Intra-class Correlation Coefficient 0.761–0.862). The variables low back pain, walking ability, social life function, and mental health had satisfactory internal consistency (the respective Cronbach's α was 0.798, 0.721, 0.707, and 0.795). Only the lumbar function parameter showed moderate reliability (Cronbach's α = 0.654). All of the variables in the Thai JOABPEQ had a statistically positive correlation with the correspondent Thai SF-36 subscales (Spearman's rank correlation p value Conclusion The Thai version of JOABPEQ had satisfactory internal consistency, test-retest reliability, and construct validity; it can be used as a reliable tool for assessing quality of life for lumbar spinal disease patients in Thailand.

Background: Pain has been regarded as important in the improvement of quality of life (QOL). In the advanced countries of Europe and the North America, a number of large-scale epidemiological surveys on pain, particularly chronic pain, have thus been performed in general populations. However, few epidemiological surveys of chronic pain have been reported from developing countries, and no surveys appear to have examined chronic pain in the least developed countries. Objectives: To compare the incidence of chronic pain in Asian countries, using Japan as an advanced country, Thailand as a developing country, and Myanmar as one of the least developed countries. Study Design: Cross-sectional study in 4 hospitals. Setting: A university hospital and a general hospital in Japan, a university hospital in Thailand, and a general hospital in Myanmar. Methods: Patients were 1,000 nursing staff working in Japan, 448 nursing staff working in Thailand, and 405 nursing staff working in Myanmar. The survey was performed by requesting all nursing staff to anonymously answer the questionnaire. Data were used to calculate chronic pain prevalence, pain site, presence or absence of consultation with doctors, methods of handling pain other than consultation with doctors, and whether pain was controlled for each country. The results were then compared between countries. Results: The prevalence of chronic pain in Myanmar was 5.9%, which was significantly lower (P < 0.01) than in Japan (17.5%) or Thailand (19.9%). The most frequent pain sites were the lower back, head, and shoulders in Japan, and the shoulders, ankle, upper back, and head in Thailand, whereas in Myanmar, no clear certain tendencies were observed. The most frequent method for handling pain other than consultation with doctors was over-the-counter drugs in Japan, massage in Thailand, and relaxation therapy (meditation) in Myanmar. Limitations: Limitations of this study were the cross-sectional design study, the small number of hospitals included, the limitation of patients to nursing staff, and the omission from the questionnaire of questions regarding body height and weight, working situation, family background, trauma history, sports activity history, smoking history, psychological/character tests, QOL, and pain levels of patients. Conclusion: The prevalence of chronic pain was significantly lower in Myanmar than in Japan or Thailand. With regard to the site and treatment of chronic pain, no clear tendencies were observed between countries, suggesting that frequency and the character of chronic pain differ from county to country around the world. Key words: Chronic pain, epidemiology, prevalence, low back pain, shoulder pain, ankle pain, headache, developing countries, least developed countries

The posterior tibial inlay technique is currently accepted as a standard operation for the posterior cruciate ligament–deficient knee. The classical technique requires a graft construct consisting of a bony part to be fitted into the posterior tibial socket. When an autogenous source is chosen, morbidity at the donor site generated by obtaining the graft with a bony part (e.g., bone–patellar tendon–bone or quadriceps tendon–bone) can be more serious than when obtaining the soft-tissue graft (e.g., hamstring). This study describes an alternative use of soft-tissue graft anchored in a bone socket at the posterior tibial margin by a transfixing cancellous screw. The graft is secured on top by a “bone washer” harvested from this bone socket to provide biological bone-tendon-bone healing. The posterior cruciate ligament remnant with integral fibers at the femur can have its tibial part revised, tensioned, and reattached concomitantly. This additional procedure is deemed to enhance joint stability and promote graft healing.

Study Design: A retrospective study. Objectives: Three objectives have been designated for this study: (1) to determine the prevalence of identifiable and non-identifiable primary tumor sites in patients with spinal metastasis, (2) to identify the most common site of the known primary tumor sites, and (3) to identify the factors associated with survival time. Summary of Background Data: The spine is the third most common metastatic site for several primary visceral carcinomas. The primary tumor site could not be identified in 15% to 20% of patients who had been diagnosed of with a skeletal metastasis. Most of the previous studies on skeletal metastasis have not been limited to spinal metastasis alone. Methods: Between January 2007 and July 2011 reviews were done for 82 patients with spinal metastasis who had not received a previous diagnosis of carcinoma. The assessment parameters included the following: general demographic data, Karnofsky score, Frankel score, number of spinal vertebra affected, region of the spine affected by metastasis, other skeletal metastasis site, visceral metastasis, known or unknown primary sites of metastasis, histological cell type of metastasis, and the survival period. The log-rank test and Cox proportional hazard model were used to study the survival analysis. Results: Of the 82 patients included in the study, 56 were male. The mean age was 57 years. 86.6% had a known primary carcinoma site while the remaining 13.4% had none. The two most common known carcinoma sites were the lung and biliary systems. Among the 11 unknown primary sites, the most common histological finding was adenocarcinoma. The mean survival period was 8.7 ± 11.7 months. The survival analysis revealed two statistically significant factors: the primary tumor site’s aggressiveness (Pthe presence of visceral metastasis (P Conclusion: The prevalence of identifiable primary site was 86.6% and the most common site was the lungs followed by the biliary system. The primary carcinoma site’s aggressiveness and the presence of visceral metastasis were the factors associated with patient survival.

Background: Osteoarthritis (OA) of the knee is prevalent and associated with both pain and functional disability. Visco-supplementation is an intra-articular therapeutic modality for the treatment of knee OA, based on the physiologic importance of hyaluronan in synovial joints. The therapeutic goal is to restore the viscoelasticity of synovial hyaluronan, decrease pain, improve mobility and restore the natural protective functions of hyaluronan in the joint radiography is currently the most widely used modality for assessing damage in OA: this technique allows the measurement of joint space width (JSW) the appropriate primary endpoint for demonstration of efficacy. There are, however, questions regarding its validity and reliability. Magnetic resonance imaging (MRI) with its superior soft tissue contrast is the best technique available for assessment of normal articular cartilage and cartilage volume. Therefore, this study aimed to evaluate the short-term benefit of intra-articular injection of hyaluronic acid (GoOn®) for protecting the articular by using MRI in patient with OA knee. Patients and Methods: This was a phase III double-blinded (i.e., both the patients and MRI examiners), randomized, controlled trial of 60 patients with mild to moderate knee OA, diagnosed according to both clinical signs and X-ray. All of the patients received MRIs (1.5 T) of the affected knee(s) at visit 0 and 6 months after the first injection. The patients received either an intra-articular injection into the affected knee weekly for 5 weeks of HA (GoOn®) or a placebo. Blinded examiners used the visual analog scale (VAS) and the WOMAC score to do weekly and monthly assessments for 6 months. The engineer used Mimics 10.01 to transform the MRI scanner data into 3D images of the articular cartilage for measuring CV, which was also blinded to the treatments. Results: Subjects averaged 59.5 years of age (range, 46 to 84). During the enrollment phase, only female farmers attended came. Four patients in the placebo group and one in the GoOn® group refused to undergo the second MRI. The mean body weight and height was 64.20 ± 10.25 kg and 1.53 ± 0.057 m, respectively. The respective baseline VAS and WOMAC score was 6.40 ± 1.64 and 51.65 ± 13.3. Forty-four patients were KL grade 2 and 16 were grade 3. The mean total CV at baseline in the GoOn® and placebo groups was 14.7 ± 3.5 ml and 15.5 ± 3.9 ml, respectively. There was no significant difference in the mean total CV after 6 months in either group (p>0.05) except at the femorotibial junction of the GoOn® group was increase CV more than the placebo group (p

We used ultrasonography in ten children with pulled elbow to compare measurements of the radiocapitellar distance (RCD) on the affected and the unaffected sides. Similar measurements were made in a group of ten age-matched normal children. The mean RCD in pronation of the affected and normal sides in the patients with pulled elbows was 7.2 mm +/- 0.7 and 3.8 mm +/- 0.5, respectively (p < 0.0001). In the normal children the mean RCD in pronation was 4.5 mm +/- 0.5. We conclude that ultrasonography is of value for documenting pulled elbow in children.