Association of phase angle with sarcopenia in chronic musculoskeletal pain patients: a retrospective study.

BACKGROUND: In chronic musculoskeletal pain patients, detection of sarcopenia is of significant clinical interest. Phase angle, which can be measured through bioelectrical impedance analysis (BIA), can detect sarcopenia; however, the evidence in chronic musculoskeletal pain patients is limited. This study aimed to assess the relationship between phase angle and sarcopenia in patients with chronic musculoskeletal pain. Our hypothesis was that phase angle would be a useful indicator to identify sarcopenia in patients with chronic musculoskeletal pain. METHODS: A total of 190 patients (51 men and 139 women) with chronic musculoskeletal pain were included in this retrospective cross-sectional study. Patient data of backgrounds, numeric rating scale score for pain, skeletal muscle index, and phase angle assessed using BIA were retrospectively reviewed. Sarcopenia was diagnosed using the Asian Working Group for Sarcopenia criteria 2019. RESULTS: A total of 51 patients (26.7%), including 10 men (19.6%) and 41 women (29.5%), were diagnosed with sarcopenia. Phase angle, sarcopenia-related factors, age, and body mass index (BMI) differed significantly in patients with and without sarcopenia. On multiple logistic regression analysis, the prevalence of sarcopenia was significantly correlated with phase angle and BMI. The areas under the curve exhibited high accuracy in discriminating sarcopenia in men and moderate accuracy in both sexes and in women. CONCLUSIONS: Phase angle may be a valid discriminator of sarcopenia in patients with chronic musculoskeletal pain.

Posterolateral Floating Technique for the Thoracic Ossification of the Posterior Longitudinal Ligament with Navigation: A Technical Note.

We describe a floating technique via a posterolateral approach with intraoperative O-arm navigation to facilitate decompression of the spinal cord in thoracic myelopathy due to severe ossification of the posterior longitudinal ligament (OPLL). A 62-year-old man with myelopathy due to thoracic OPLL had left-leg muscle weakness, urinary disturbance, and spastic gait. Bilateral leg pain and gait disturbance had persisted for 2 years. He was successfully treated by the posterolateral OPLL floating procedure and posterior pedicle fixation under O-arm navigation. At a 2-year follow-up, manual muscle testing results and sensory function of the left leg had recovered fully. His cervical Japanese Orthopedic Association score had improved from 5/12 to 11/12. The novel intraoperative O-arm navigation-guided posterolateral floating procedure for thoracic OPLL is effective for achieving precise decompression and strong fixation with a posterior approach only and can provide an excellent result for severe thoracic OPLL without the risk of adverse events from intraoperative radiation.

Factors influencing caregiver burden in chronic pain patients: A retrospective study.

Chronic pain coexists with disability, anxiety, depression, and sleep disturbances, which are factors of pain chronicity in the fear-avoidance model. Self-efficacy for managing pain plays a protective role against pain chronicity. For chronic pain sufferers, social support from caregivers is important. However, such caregivers face enormous physical and mental burdens. This study aimed to assess how self-efficacy and factors related to the fear-avoidance model affect caregiver burden. Participants were 135 chronic pain patients and their caregivers who visited our outpatient pain special clinic. In clinical assessments, numeric rating scale (NRS), pain catastrophizing scale (PCS), hospital anxiety and depression scale (HADS), Athens insomnia scale (AIS), pain disability assessment scale (PDAS), pain self-efficacy questionnaire (PSEQ) for the patients and Zarit Burden Interview (ZBI) for their caregivers were evaluated. Participants were divided into 2 groups (L group ZBI < 24 points and H group ZBI ≥ 24 points) and compared. Regression analyses were conducted to identify factors correlated with the ZBI scores. Compared to L group, H group showed significantly higher NRS and HADs depression scores, and lower PSEQ scores. In univariate regression analysis, ZBI scores were significantly correlated with NRS, PCS, HADS anxiety, HADS depression, PDAS and PSEQ. Multiple linear regression analysis revealed that ZBI scores were significantly correlated with PSEQ. The caregivers who perceived high caregiver burden had significantly higher patients' pain intensity, depression, and lower self-efficacy than those who perceived low caregiver burden. Caregiver burden correlated with the pain intensity, pain catastrophizing, anxiety, depression, disability, and self-efficacy of chronic pain patients. Among these factors, self-efficacy was the most negatively correlated with caregiver burden. Treatments focused on increasing self-efficacy for managing pain have the potential to reduce caregiver burden.

Evaluation of SARC-F and SARC-CalF for sarcopenia screening in patients with chronic musculoskeletal pain: A prospective cross-sectional study.

OBJECTIVES: Early sarcopenia detection using screening tools, such as SARC-F and SARC-CalF, has been proven reliable. However, the relationship between chronic musculoskeletal pain with sarcopenia is unknown. This study assessed sarcopenia morbidity as well as the reliability of sarcopenia screening with SARC-F and SARC-CalF in patients with chronic musculoskeletal pain. METHODS: Overall, 172 patients with chronic musculoskeletal pain were included in this cross-sectional study. All participants completed the SARC-F, SARC-CalF, numeric rating scale (NRS), and pain disability assessment scale (PDAS) assessments. Sarcopenia was diagnosed using the Asian Working Group for Sarcopenia criteria 2019. Correlations between SARC-F and SARC-CalF scores and each measured variable were evaluated using univariate and multiple linear regression analyses. A receiver operating characteristic curve analysis was conducted, and reliabilities of SARC-F and SARC-CalF scores for diagnosing sarcopenia were compared. RESULTS: Thirty-nine patients were diagnosed with sarcopenia. Among these, 10 patients were <65 years old, and 29 were >65 years old. Both SARC-F and SARC-CalF scores significantly correlated with grip power, gait speed, skeletal mass index, numeric rating scale score, and PDAS score. In multiple linear regression analysis, SALC-F and SALC-CalF scores significantly correlated with PDAS score, skeletal mass index, and gait speed. The area under the curve were 0.70 for SARC-F and 0.88 for SARC-CalF; SARC-CalF had a significantly higher area under the curve than SARC-F. DISCUSSION: Sarcopenia was diagnosed in patients aged <65 years with chronic musculoskeletal pain. SALC-F and SARC-CalF scores showed a significant correlation with disability due to pain and were reliable sarcopenia screening tools for chronic musculoskeletal pain. SARC-CalF was more reliable than SARC-F.

Mechanical Study of Various Pedicle Screw Systems including Percutaneous Pedicle Screw in Trauma Treatment.

Background and Objectives: Spine surgery using a percutaneous pedicle screw placement (PPSP) is widely implemented for spinal trauma. However, percutaneous systems have been reported to have weak screw-rod connections. In this study, conventional open and percutaneous systems were biomechanically evaluated and compared. Material and Methods: The experiments were performed in two stages: the first stage was a break test, whereas the second stage was a fatigue test. Four systems were used for the experiments. System 1 was intended for conventional open surgery (titanium rod with a 6.0 mm diameter, using a clamp connecting mechanism). System 2 was a percutaneous pedicle screw (PPS) system for trauma (titanium alloy rod with a 6.0 mm diameter, using ball ring connections). System 3 was a PPS system for trauma (cobalt-chromium alloy rod with a 6.0 mm diameter, using sagittal adjusting screw connections). System 4 was a general-purpose PPS system (titanium alloy rod with a 5.5 mm diameter, using a mechanism where the adapter in the head holds down the screw). Results: Stiffness values of 54.8 N/mm, 43.1 N/mm, 90.9 N/mm, and 39.3 N/mm were reported for systems 1, 2, 3, and 4, respectively. The average number of load cycles in the fatigue test was 134,393, 40,980, 1,550,389, and 147,724 for systems 1 to 4, respectively. At the end of the test, the displacements were 0.2 mm, 16.9 mm, 1.2 mm, and 8.6 mm, respectively. System 1, with a locking mechanism, showed the least displacement at the end of the test. Conclusion: A few PPS systems showed better results in terms on stiffness and life than the open system. The experiments showed that mechanical strength varies depending on the spinal implant. The experiments conducted are essential and significant to provide the mechanical strength required for surgical reconstruction.

Long-Term Results of Posterior Vertebral Column Resection for Severe Thoracolumbar Kyphosis with Achondroplastic Patients: A Case Series.

Background and Objectives: Thoracolumbar kyphosis is one of the most frequent skeletal manifestations in patients with achondroplasia. Few papers have been published on the surgical treatment of this condition, especially in skeletally mature patients. With this study, we presented a retrospective case series of long-term surgical results for achondroplastic patients with severe thoracolumbar kyphosis. This study was conducted to evaluate the outcome of surgical treatment for thoracolumbar kyphosis in patients associated with achondroplasia presenting with paraparesis. Materials and Methods: Three patients with achondroplasia who developed neurologic deficits due to severe thoracolumbar kyphosis and underwent surgical treatment were evaluated (mean age 22.3 years; mean follow-up 9.3 years). All patients were treated with posterior vertebral column resection (p-VCR) of hypoplastic apical vertebrae with a cage and segmental instrumentation. Neurologic outcomes (JOA scores), correction of kyphosis, and operative complications were assessed. Results: All patients had back pain, neurological deficits, and urinary disturbance before surgery. The average preoperative JOA score was 8.3/11 points, which was improved to 10.7/11 points at the final follow-up (mean recovery rate 83%). All patients obtained neurologic improvement after surgery. The mean preoperative kyphotic angle was 117° (range 103°-126°). The postoperative angles averaged 37° (range 14°-57°), resulting in a mean correction rate of 67%. All patients had postoperative complications such as rod breakage and/or surgical site infection. Conclusions: The long-term results of p-VCR were acceptable for treating thoracolumbar kyphosis in patients with achondroplasia. To perform this p-VCR safely, spinal navigation and neuromonitoring are inevitable when resecting non anatomical fused vertebrae and ensuring correct pedicle screw insertion. However, surgical complications such as rod breakage and surgical site infection may occur at a high rate, making informed consent very important when surgery is indicated.

C-arm Free O-arm Navigated Posterior Atlantoaxial Fixation in Down Syndrome: A Technical Note.

The surgical treatment of pediatric atlantoaxial subluxation (AAS) in Down syndrome (DS) remains technically challenging due to radiation exposure and complications such as vertebral artery injury and nonunion. The established treatment is fixation with a C1 lateral mass screw and C2 pedicle screw (modified Goel technique). However, this technique requires fluoroscopy for C1 screw insertion. To avoid exposing the operating team to radiation we present here a new C-arm free O-arm navigated surgical procedure for pediatric AAS in DS. A 5-year-old male DS patient had neck pain and unsteady gait. Radiograms showed AAS with an atlantodental interval of 10 mm, and irreducible subluxation on extension. CT scan showed Os odontoideum and AAS. MRI demonstrated spinal cord compression between the C1 posterior arch and odontoid process. We performed a C-arm free O-arm navigated modified Goel procedure with postoperative halo-vest immobilization. At oneyear follow-up, good neurological recovery and solid bone fusion were observed. The patient had no complications such as epidural hematoma, infection, or nerve or vessel injury. This novel procedure is a useful and safe technique that protects surgeons and staff from radiation risk.

Three-Dimensional Analysis of the Ideal Entry Point for Sacral Alar Iliac Screws.

STUDY DESIGN: This is a virtual three-dimensional (3D) imaging study examining computed tomography (CT) data to investigate instrumentation placement. PURPOSE: In this study, we aim to clarify the ideal entry point and trajectory of the sacral alar iliac (SAI) screw in relationship to the dorsal foramen at S1 and the respective nerve root. OVERVIEW OF LITERATURE: To the best of our knowledge, there is yet no detailed 3D imaging study on the ideal entry point of the SAI screw. Despite the evidence suggesting that the dorsal foramen at S1 is a landmark on the sacrum, the S1 nerve root disruption is a general concern during the insertion of SAI screws. No other study has been published examining the nerve root location at the S1and SAI screw insertions. METHODS: Preoperative CT data from 26 patients pertaining to adult spinal deformities were investigated in this study. We applied a 3D image processing method for a detailed investigation. Virtual cylinders were used to mimic SAI screws. These were placed to penetrate the sacral iliac joint without violating the other cortex. We then assessed the trajectory of the longest SAI screw and the ideal entry point of SAI using a color mapping method on the surface of the sacrum. We measured the location of the nerve root at S1 in relation to the foramen at S1 and the sacral surface. RESULTS: As per the results of our color mapping, it was determined that areas that received high scores are located medially and caudally to the dorsal foramen of S1. The mean angle between a horizontal line and a line connecting the medial edge of the foramen and nerve root at S1 was 93.5°. The mean distances from the dorsal medial edge of the foramen and sacral surface to S1 nerve root were 21.8 mm and 13.9 mm, respectively. CONCLUSIONS: The ideal entry point of the SAI screw is located medially and caudally to the S1 dorsal foramen based on 3D digital mapping. It is also shown that this entry point spares the S1 nerve root from possible iatrogenic injuries.

Psoas muscle index predicts osteoporosis and fracture risk in individuals with degenerative spinal disease.

OBJECTIVES: Skeletal muscle loss and osteoporosis are major medical and socioeconomic concerns as the global population ages. Studies have reported that skeletal muscle mass correlates to bone mineral density (BMD). The psoas muscle index (PMI), measured as the L3 cross-sectional areas of the right and left psoas divided by the square of height, has a positive correlation with the total volume of skeletal muscle in the body. This study aimed to evaluate relationships between PMI and BMD and fracture risk estimated by the Fracture Risk Assessment Tool (FRAX). METHODS: Preoperatively acquired, plain computed tomography images at the L3 level were used to measure PMI in 87 people with degenerative spinal diseases. We evaluated the correlation between PMI and BMD and fracture risk estimated by FRAX. RESULTS: PMI was significantly correlated with BMD in the entire lumbar spine and femoral neck (r = 0.413 and 0.525, both P < 0.001). People with osteoporosis showed significantly lower PMI than those without (P < 0.05). PMI was also significantly correlated with FRAX score (r = -0.545, P < 0.001). Furthermore, based on the recommendation of osteoporosis treatment, participants were divided into two groups: FRAX ≥15% (R group) and FRAX <15% (C group). The R group showed significantly lower PMI than the C group (P < 0.001). Receiver operating characteristic curve analysis revealed that PMI has moderate accuracy in diagnosing osteoporosis and FRAX ≥15%. CONCLUSIONS: PMI was significantly associated with BMD and fracture risk. PMI measurement is straightforward and may increase the diagnosis rate of osteoporosis and fracture risk.

Comparative Study of Bilateral Dual Sacral-Alar-Iliac Screws versus Bilateral Single Sacral-Alar-Iliac Screw for Adult Spine Deformities.

OBJECTIVE: To evaluate the feasibility of O-arm navigation of bilateral dual sacral-alar-iliac (SAI) screws compared with conventional bilateral single SAI and S1 pedicle screws for pelvic anchors in cases of adult spinal deformity. METHODS: This retrospective, comparative study included 39 patients who underwent corrective fusion using SAI screws from T10 to the pelvis. Patients were divided into 2 groups according to the number of SAI screws placed during adult spinal deformity surgery: single SAI screw (group S, 17 cases) and dual SAI screws (group D, 22 cases). The incidence of rod breakage, proximal junctional kyphosis, screw loosening, reoperation, and global alignment in each group was estimated. Postoperative patient-reported outcomes were measured using the Oswestry Disability Index, Japanese Orthopaedic Association Back Pain Evaluation Questionnaire, and visual analog scale. RESULTS: The incidence of SAI screw loosening was significantly lower in group D than in group S (23% vs. 65%, P = 0.011). The rod breakage incidence was 0% and 12% in groups D and S, respectively (P = 0.17). There were no significant differences in the postoperative global alignment and clinical outcomes between the 2 groups. CONCLUSIONS: Dual SAI screws were associated with a significantly reduced incidence of screw loosening compared with single SAI screws. The bilateral dual SAI screws technique for pelvic anchors is feasible for the treatment of patients with adult spinal deformity.

Minimally Invasive L5 Corpectomy with Navigated Expandable Vertebral Cage: A Technical Note.

BACKGROUND: Conventional L5 corpectomy requires a large incision and an extended period of intraoperative fluoroscopy. We describe herein a new L5 corpectomy technique. METHODS: A 79-year-old woman was referred to our hospital for leg pain and lower back pain due to an L5 vertebral fracture. Her daily life had been affected by severe lower back pain and sciatica for more than 2 months. We initially performed simple decompression surgery, but this proved effective for only 10 months. RESULTS: For revision surgery, the patient underwent minimally invasive L5 corpectomy with a navigated expandable cage without fluoroscopy. The second surgery took 215 min, and estimated blood loss was 750 mL. The revision surgery proved successful, and the patient could then walk using a cane. In terms of clinical outcomes, the Oswestry Disability Index improved from 66% to 24%, and the visual analog scale score for lower back pain improved from 84 to 31 mm at the 1-year follow-up. CONCLUSIONS: Minimally invasive L5 corpectomy with a navigated expandable vertebral cage is effective for reducing cage misplacement and surgical invasiveness. With this new technique, surgeons and operating room staff can avoid the risk of adverse events due to intraoperative radiation exposure.

Assessment of the Concordance Rate between Intraoperative Pathological Diagnosis and the Final Pathological Diagnosis of Spinal Cord Tumors.

The intraoperative pathological diagnosis (IPD) plays an important role in determining the optimal surgical treatment for spinal cord tumors. The final pathological diagnosis (FPD) is sometimes different from the IPD. Here, we sought to identify the accuracy of the IPD of spinal cord tumors compared to the FPD. We retrospec-tively analyzed the cases of 108 patients with spinal cord tumors treated surgically in our institute; the IPD, FPD, mismatched cases, and concordance rate between the IPD and FPD were investigated. Five cases involved a mismatch between the IPD and FPD. The overall concordance rate was 95.4%, with 90.9% for extra-dural lesions, 98.5% for intradural extramedullary lesions, 84.2% for intramedullary lesions, and 100% for dumbbell-type tumors. The concordance rate of intramedullary lesions tended to be lower than that of other lesions (p = 0.096). A lower concordance rate was revealed for intramedullary lesions compared to the other lesions. Despite the IPD clearly remaining a valuable tool during operative procedures, surgeons should recog-nize the limitations of IPDs and make comprehensive decisions about surgical treatments.

Maximal Resection of Intramedullary Lipoma Using Intraoperative Ultrasonography: A Technical Note.

One of the problems during surgery for intramedullary lipoma is the ambiguous boundary between the lipoma and the spinal cord, resulting in either incomplete resection or damage to the spinal cord. We report a case of intramedullary lipoma resection on a 61-year-old man in which the boundary between the tumor and spinal cord was repeatedly visualized with intraoperative ultrasonography. We focused on the distinctive features of fat as hyperechoic, in contrast to low-echo neural tissue. Subtotal resection of the tumor was achieved without any aggravation of neurological symptoms. Intraoperative ultrasonography may be useful for confirming tumor boundaries during intramedullary lipoma resection.

Cobalt-chromium versus titanium alloy rods for correction of adolescent idiopathic scoliosis based on 1-year follow-up: a multicenter randomized controlled clinical trial.

OBJECTIVE: For instrumented correction surgery for adolescent idiopathic scoliosis (AIS), surgeons are increasingly switching from titanium (Ti) alloy rods to stiffer cobalt-chromium (CoCr) rods. The authors conducted the first multicenter randomized controlled clinical trial to investigate whether these materials affect the outcomes in terms of spine correction and quality of life (QOL). This trial was registered at UMIN Clinical Trials Registry on September 3, 2012, under the identifier UMIN000008838 (level of evidence 1). METHODS: Female AIS patients (Lenke types 1-3, patient age 10-19 years) were recruited at 5 Japanese institutions and randomized into two cohorts: 6.0-mm-diameter Ti rods were placed in one group, and 6.0-mm-diameter CoCr rods were placed in the other. Patients were followed up at 2 weeks and 3, 6, and 12 months with radiographic examination to quantify the sagittal and coronal correction (Cobb angle, thoracic kyphosis, rib hump, and apical vertebral rotation). Patients completed questionnaires (Scoliosis Research Society-22r, 12-Item Short-Form Health Survey, and Scoliosis Japanese Questionnaire-27) at 6 and 12 months to assess QOL. RESULTS: A total of 69 AIS patients were randomized to the demographically similar Ti (n = 37) or CoCr (n = 32) cohort. Four adverse events were recorded, two in each cohort, but these were not related to the rod material. At the final follow-up, both Ti and CoCr cohorts showed significant improvement in spinal correction, including the Cobb angle, thoracic kyphosis, and rib hump size. The correction rates were 68.4% and 67.1% for the Ti and CoCr cohorts, respectively. No parameters differed significantly between the cohorts at any time. Survey data showed improved but similar outcomes in both cohorts. CONCLUSIONS: Both treatments (Ti and CoCr) produced similar results and were efficient in engendering clinically significant spine corrections. Clinical trial registration no.: UMIN000008838 (UMIN Clinical Trials Registry).

Quantification of patellar tendon reflex using portable mechanomyography and electromyography devices.

Deep tendon reflexes are one of the main components of the clinical nervous system examinations. These assessments are inexpensive and quick. However, evaluation can be subjective and qualitative. This study aimed to objectively evaluate hyperreflexia of the patellar tendon reflex using portable mechanomyography (MMG) and electromyography (EMG) devices. This study included 10 preoperative patients (20 legs) who had a pathology that could cause bilateral patellar tendon hyperreflexia and 12 healthy volunteers (24 legs) with no prior history of neurological disorders. We attached MMG/EMG sensors onto the quadriceps and tapped the patellar tendon with maximal and constant force. Our results showed a significantly high amplitude of the root mean square (RMS) and low frequency of the mean power frequency (MPF) in the rectus femoris, vastus medialis, and vastus lateralis muscles in both EMG and MMG with both maximal and constant force. Especially in the patients with cervical and thoracic myelopathy, the receiver operating characteristic (ROC) curve for diagnosing hyperreflexia of the patellar tendon showed a moderate to very high area under the curve for all EMG-RMS, EMG-MPF, MMG-RMS, and MMG-MPF values. The use of EMG and MMG for objectively quantifying the patellar tendon reflex is simple and desirable for future clinical applications and could help diagnose neurological disorders.

Cognitive factors associated with locomotive syndrome in chronic pain patients: A retrospective study.

BACKGROUND: Prevention and treatment for locomotive syndrome (LS) are important for extending healthy life expectancy. The 25-question geriatric locomotive function scale (GLFS-25) was developed to diagnose LS. The Fear-Avoidance model was proposed to explain pain chronicity. LS and chronic pain decrease activities of daily living; however, the relationships between LS and factors related to chronic pain in the Fear-Avoidance model are unknown. Objective of the current study was to assess the prevalence of LS and examine the factors of the Fear-Avoidance model and the GLFS-25 that affect the prevalence of LS in patients with chronic pain. METHODS: Participants included 281 patients (99 men, 182 women) aged over 40 years with chronic pain who visited our outpatient clinic for chronic pain. All participants completed the GLFS-25, numeric rating scale (NRS), pain catastrophizing scale (PCS), hospital anxiety and depression scale (HADS), and Athene insomnia scale (AIS). According to a GLFS-25 cutoff point, participants were divided into three groups (LS-2; GLFS-25 ≥ 16, LS-1; 7 ≤ GLFS-25 < 16, and non-LS; GLFS-25 < 7 points) and each parameter was compared among the groups, followed by multiple logistic regression analysis. Next, multiple linear regression analysis was performed to determine the factors associated with the GLFS-25. RESULTS: Of all 281 patients, 241 (85.8%) patients were diagnosed with LS-2. Univariate analysis revealed there were significant differences in NRS, PCS, HADS anxiety, HADS depression, and AIS among groups. Multiple logistic regression analyses showed PCS was significantly associated with LS-2 prevalence. The GLFS-25 was positively correlated with NRS, HADS depression, AIS in multiple linear regression analysis. CONCLUSIONS: We found that patients with chronic pain in our outpatient clinic had a significant rate of LS-2. The prevalence of LS-2 was significantly correlate with pain catastrophizing, and the GLFS-25 was significantly correlated with higher pain intensity, depression, and insomnia.

Short-term outcomes of mirogabalin in patients with peripheral neuropathic pain: a retrospective study.

BACKGROUND: Mirogabalin, which is approved for the treatment of peripheral neuropathic pain in Japan, is a ligand for the α2δ subunit of voltage-gated calcium channels. Both pregabalin and mirogabalin act as nonselective ligands at the α2δ-1 and α2δ-2 subunits. Mirogabalin has a unique binding profile and long duration of action. Pregabalin has been reported to produce intolerable adverse effects in some patients. This study investigated outcomes associated with mirogabalin administration in patients with peripheral neuropathic pain who ceased treatment with pregabalin. METHODS: We retrospectively assessed peripheral neuropathic pain using the neuropathic pain screening questionnaire (NeP score) in 187 patients (58 men, 129 women) who were treated with mirogabalin. All patients had switched from pregabalin to mirogabalin due to lack of efficacy or adverse events. Differences in the treatment course (i.e., numeric rating scale (NRS) scores) were compared using one-way analysis of variance with Bonferroni post hoc tests. RESULTS: The mean age of the patients was 72.3 years (range, 30-94 years), and the mean duration of disease was 37 months (range, 3-252 months). After treatment with mirogabalin for 1 week, NRS scores significantly decreased compared with baseline and continued to decrease over time. After 8 weeks, NRS scores improved by ≥ 30% from baseline in 113 patients (69.3%). Twenty-four patients (12.8%) stopped mirogabalin treatment due to adverse events. Somnolence (26.7%), dizziness (12.3%), edema (5.9%), and weight gain (0.5%) were noted as adverse events of mirogabalin. CONCLUSIONS: The results of this investigation indicate that mirogabalin is safe and effective for reducing peripheral neuropathic pain.

Multipotent Neurotrophic Effects of Hepatocyte Growth Factor in Spinal Cord Injury.

Spinal cord injury (SCI) results in neural tissue loss and so far untreatable functional impairment. In addition, at the initial injury site, inflammation induces secondary damage, and glial scar formation occurs to limit inflammation-mediated tissue damage. Consequently, it obstructs neural regeneration. Many studies have been conducted in the field of SCI; however, no satisfactory treatment has been established to date. Hepatocyte growth factor (HGF) is one of the neurotrophic growth factors and has been listed as a candidate medicine for SCI treatment. The highlighted effects of HGF on neural regeneration are associated with its anti-inflammatory and anti-fibrotic activities. Moreover, HGF exerts positive effects on transplanted stem cell differentiation into neurons. This paper reviews the mechanisms underlying the therapeutic effects of HGF in SCI recovery, and introduces recent advances in the clinical applications of HGF therapy.

Minimally Invasive Percutaneous Spinopelvic Fixation for Unstable Pelvic Ring Fracture Performed With the Patient in a Lateral Position.

Spinopelvic fixation provides a strong fixation for unstable pelvic ring fractures. However, the technique is usually performed with the patient in the prone position, with the applied weight on the anterior superior iliac crests aggravating fracture displacement. We developed a novel approach for minimally invasive percutaneous spinopelvic fixation that is performed with the patient in a lateral (side lying) position. We describe the application of our technique for the treatment of a bilateral pelvic ring and acetabulum fracture in a 79-year-old woman injured in a traffic accident. Initial posterior fixation was performed with the patient in the left-side lying position, using bilateral pedicle screws at L3 and L4 and a left sacral-alar iliac screw and 2 right iliac screws inserted under navigation. The lateral and cranial displacement of the right pelvic ring was reduced percutaneously. One week after this initial surgery, we proceeded with an open anterior reduction and internal fixation of the left pelvic ring and acetabulum fracture. The postoperative course was uneventful and clinical outcomes were satisfactory. Reduction of a pelvic ring fracture in a lateral position, with subsequent spinopelvic fixation, is a reasonable option for the treatment of an unstable pelvic ring fracture.

The factors driving self-efficacy in intractable chronic pain patients: a retrospective study.

BACKGROUND: The fear-avoidance model is a theoretical paradigm for explaining acute and chronic pain. In this model, pain catastrophizing plays an important role. On the other hand, self-efficacy influences whether patients view their pain optimistically, ultimately preventing the conversion of pain into intractable pain. The aim of the present study was to evaluate the factors that influence self-efficacy in patients with chronic pain. METHODS: Study participants included 147 outpatients (35 men, 112 women) with intractable chronic pain who visited our hospital between September 2014 and July 2015. Their mean age was 71.0 (range 32-92) years. Pain sites were as follows: low back, 97 patients; knee, 71 patients; shoulder, 34 patients; and hip, 15 patients. All patients were assessed using the following measures: Numeric Rating Scale (NRS), Pain Catastrophizing Scale (PCS), Hospital Anxiety and Depression Scale (HADS), Pain Disability Assessment Scale (PDAS), and Pain Self-Efficacy Questionnaire (PSEQ). All participants were further divided into two groups based on median PSEQ scores (group L: PSEQ of 35 points or less, n = 74; group H: PSEQ greater than 35 points, n = 73). The factors that influenced self-efficacy in these patients were analyzed using univariate and multiple linear regression analyses. RESULTS: Significant differences were observed in gender; pain duration; and NRS, PDAS, HADS, and PCS scores between group L and group H. Multiple linear regression analysis revealed that self-efficacy was correlated with PDAS score, HADS depression score, and pain duration. CONCLUSIONS: Patients with longer pain duration indicated greater self-efficacy and patients with higher pain disability and depression exhibited lower self-efficacy.