Assessing paraspinal muscle atrophy with electrical impedance myography: Limitations and insights.

Paraspinal muscle atrophy is gaining attention in spine surgery due to its link to back pain, spinal degeneration and worse postoperative outcomes. Electrical impedance myography (EIM) is a noninvasive diagnostic tool for muscle quality assessment, primarily utilized for patients with neuromuscular diseases. However, EIM's accuracy for paraspinal muscle assessment remains understudied. In this study, we investigated the correlation between EIM readings and MRI-derived muscle parameters, as well as the influence of dermal and subcutaneous parameters on these readings. We retrospectively analyzed patients with lumbar spinal degeneration who underwent paraspinal EIM assessment between May 2023 to July 2023. Paraspinal muscle fatty infiltration (FI) and functional cross-sectional area (fCSA), as well as the subcutaneous thickness were assessed on MRI scans. Skin ultrasound imaging was assessed for dermal thickness and the echogenicities of the dermal and subcutaneous layers. All measurements were performed on the bilaterally. The correlation between EIM readings were compared with ultrasound and MRI parameters using Spearman's correlation analyses. A total of 20 patients (65.0% female) with a median age of 69.5 years (IQR, 61.3-73.8) were analyzed. The fCSA and FI did not significantly correlate with the EIM readings, regardless of frequency. All EIM readings across frequencies correlated with subcutaneous thickness, echogenicity, or dermal thickness. With the current methodology, paraspinal EIM is not a valid alternative to MRI assessment of muscle quality, as it is strongly influenced by the dermal and subcutaneous layers. Further studies are required for refining the methodology and confirming our results.

Symmetry in Paraspinal Muscles as a Predictor of the Development of Pregnancy-Related Low Back and Pelvic Pain: A Prospective Study.

OBJECTIVE: To determine the asymmetry in the paraspinal muscle before pregnancy and evaluate its association with pregnancy-associated lumbopelvic pain (LPP). METHODS: This was a prospective case-control study conducted from January 2017 and December 2018. A total of 171 subjects (mean age ± SD, 27.4 ± 5.8 years) were finally divided into the LBP group, PGP group, and no LPP group. Each subject was asked to follow a standardized clinical imaging protocol before the pregnancy. The area of muscles (multifidus, erector spinae, and psoas muscles) on the axial slice at mid-disc of L4 -L5 and L5 -S1 were segmented and then the cross-sectional area (CSA) of a particular muscle was measured by outlining the innermost fascial border surrounding each muscle. The mean value of F-CSA's ratio to T-CSA (F/T CSA) was used to determine whether the bilateral paraspinal muscle was asymmetrical. Total muscle CSA (T-CSA) represents the sum of CSA of interested three muscles. The signal intensity can distinguish fat and muscle tissue in a different range. Based on this, functional CSA (F-CSA), represented by fat-free area, was evaluated quantitively by excluding the signal of the deposits of intramuscular fat. Total muscle CSA (T-CSA), functional CSA (F-CSA), and the ratio of F-CSA to T-CSA (F/T CSA) were measured unilaterally and compared between groups. Logistic regression was performed to determine the risk factors for pregnancy-associated LPP. The Pearson correlation coefficient was performed to test the relationship between asymmetry in F/T-CSA and pain rating. RESULTS: A total of 124 subjects (72.5%) (28.5 ± 5.2 years) had LPP during pregnancy. Forty-eight (38.7%) individuals had low back pain (LBP) and 76 (61.3%) had pelvic girdle pain (PGP). Seventy-six women (44.4%) were determined to have asymmetry in paraspinal muscle according to the definition in this methods section. The duration of follow-up was 24 months postpartum. A total of 39 (31.5%) women unrecovered from LPP. F/T-CSA was significantly decreased for LBP in the PGP group than in the and control group (0.03 ± 0.02 vs 0.05 ± 0.03 vs 0.12 ± 0.05, P < 0.001). Meanwhile, significant differences were detected in both groups (all P < 0.001). In patients with LBP, the level of paraspinal asymmetry, represented by the difference in F/T-CSA, was positively correlated with pain scores (r = 0.52, P < 0.01). However, no statistically significant correlation between pain scores and paraspinal asymmetry was found in PGP (r = 0.42, P > 0.05). Asymmetry in the paraspinal muscle (adjusted OR = 1.5), LBP (adjusted OR = 1.6), LPP in a previous pregnancy (adjusted OR = 1.4), sick leave ≥90 days (adjusted OR = 1.2), and heavy labor (adjusted OR = 1.2) were risk factors for the unrecovered LPP during pregnancy. CONCLUSIONS: Asymmetrical muscular compositions could lead to abnormal biomechanics for the segmental motions. Lateral-directed physical training and stretching may help decrease the occurrence and severity of this condition.

Prognostic implication of erector spinae muscles in non-small-cell lung cancer patients treated with immuno-oncology combinatorial chemotherapy.

BACKGROUND: The quantity of skeletal muscles has recently been reported to have prognostic value in patients with non-small-cell lung cancer (NSCLC) treated with second-line immunotherapy. However, the prognostic role of skeletal muscle assessment in NSCLC patients undergoing first-line immuno-oncology (IO) combinatorial treatment (IO-chemotherapy) has not been elucidated. METHODS: We retrospectively reviewed 36 patients with NSCLC undergoing first-line IO-chemotherapy between April 2018 and June 2021 in our hospital. The cross-sectional area of the erector spinae muscle (ESMCSA ) was evaluated by manual tracing on computed tomography scans at the level of the 12th thoracic vertebra before initiating IO-chemotherapy. To minimize deviation due to physique, the ESMCSA was adjusted by body surface area (BSA) (ESMCSA to BSA ratio: ESMCSA /BSA). A survival time analysis was performed using the Kaplan-Meier method and log-rank test. A multivariate analysis with Cox proportional hazards model was conducted to investigate the prognostic value of the ESMCSA /BSA and inflammatory and nutritional indices. RESULTS: The median progression-free survival (PFS) and overall survival (OS) were 6.5 and 16.6 months, respectively. Intergroup comparison by the log-rank test revealed that there was no significant difference in the median PFS, but the median OS was significantly long in the high ESMCSA /BSA (>19 cm2/ m2 ) (high ESMCSA /BSA group, p = 0.0373). The multivariate analysis showed that ESMCSA /BSA was an independent prognostic factor for OS (hazard ratio 0.79, p = 0.044). CONCLUSIONS: The results of this study indicate that the pretreatment ESMCSA /BSA may be a potential prognostic factor in NSCLC patients receiving first-line IO-chemotherapy.

COVID-19 and Myositis: What We Know So Far.

PURPOSE: Myositis as a rare manifestation of COVID-19 is only recently being reported. This review examines the current literature on COVID-19-induced myositis focusing on etiopathogenesis, clinical presentations, diagnostic practices, and therapeutic challenges with immunosuppression, and the difficulties experienced by rheumatologists in established myositis in the COVID-19 era. RECENT FINDINGS: COVID-19 is associated with a viral myositis attributable to direct myocyte invasion or induction of autoimmunity. COVID-19-induced myositis may be varied in presentation, from typical dermatomyositis to rhabdomyolysis, and a paraspinal affliction with back pain. It may or may not present with acute exponential elevations of enzyme markers such as creatine kinase (CK). Virus-mediated muscle inflammation is attributed to ACE2 (angiotensin-converting enzyme) receptor-mediated direct entry and affliction of muscle fibers, leading on to innate and adaptive immune activation. A greater recognition of the stark similarity between anti-MDA5-positive myositis with COVID-19 has thrown researchers into the alley of exploration - finding common etiopathogenic basis as well as therapeutic strategies. For patients with established myositis, chronic care was disrupted during the pandemic with several logistic challenges and treatment dilemmas leading to high flare rates. Teleconsultation bridged the gap while ushering in an era of patient-led care with the digital transition to tools of remote disease assessment. COVID-19 has brought along greater insight into unique manifestations of COVID-19-related myositis, ranging from direct virus-induced muscle disease to triggered autoimmunity and other etiopathogenic links to explore. A remarkable shift in the means of delivering chronic care has led patients and caregivers worldwide to embrace a virtual shift with teleconsultation and opened doorways to a new era of patient-led care.

Cervical Paraspinal Muscle Fatty Degeneration Is Not Associated with Muscle Cross-sectional Area: Qualitative Assessment Is Preferable for Cervical Sarcopenia.

BACKGROUND: Sarcopenia, defined as decreased skeletal mass, is an independent marker of frailty that is not accounted for by other risk-stratification methods. Recent studies have demonstrated a clear association between paraspinal sarcopenia and worse patient-reported outcomes and complications after spine surgery. Currently, sarcopenia is characterized according to either a quantitative assessment of the paraspinal cross-sectional area or a qualitative analysis of paraspinal fatty infiltration on MRI. No studies have investigated whether the cervical paraspinal cross-sectional area correlates with fatty infiltration of the cervical paraspinal muscles on advanced imaging. QUESTION/PURPOSE: Do patients undergoing anterior cervical discectomy and fusion (ACDF) with increasing paraspinal fatty degeneration on advanced imaging also demonstrate decreased cervical paraspinal cross-sectional area? METHODS: Between 2011 and 2017, 98 patients were prospectively enrolled in a database of patients undergoing one- to three-level ACDF for degenerative conditions at a single institution. To be eligible for this prospective study, patients were required to undergo an MRI before surgery, be older than 18 years, and have no previous history of cervical spine surgery. Two independent reviewers, both surgeons not involved in the patients' care and who were blinded to the clinical outcomes, retrospectively assessed the paraspinal cross-sectional area and Goutallier classification of the right-sided paraspinal muscle complex. We then compared the patients' Goutallier grades with their paraspinal cross-sectional area measurements. We identified 98 patients for inclusion. Using the Fuchs modification of the Goutallier classification, we classified the fatty degeneration of 41 patients as normal (Goutallier Grades 0 to 1), that of 47 patients as moderate (Grade 2), and that of 10 patients as severe (Grades 3 to 4). We used ANOVA to compare all means between groups. RESULTS: There was no difference in the mean paraspinal cross-sectional area of the obliquus capitus inferior (normal 295 ± 81 mm2; moderate 317 ± 104 mm2; severe 300 ± 79 mm2; p = 0.51), multifidus (normal 146 ± 59 mm2; moderate 170 ± 70 mm2; severe 192 ± 107 mm2; p = 0.11), or sternocleidomastoid (normal 483 ± 150 mm2; moderate 468 ± 149 mm2; severe 458 ± 183 mm2; p = 0.85) among patients with mild, moderate, and severe fatty infiltration based on Goutallier grading. There was a slightly greater longus colli cross-sectional area in the moderate and severe fatty infiltration groups (74 ± 22 mm2 and 66 ± 18 mm2, respectively) than in the normal group (63 ± 15 mm2; p = 0.03). CONCLUSION: Because our study demonstrates minimal association between paraspinal cross-sectional area and fatty infiltration of the cervical paraspinals, we recommend that physicians use the proven qualitative assessment of paraspinal fatty infiltration during preoperative evaluation of patients who are candidates for ACDF. Future studies investigating the relationship between cervical paraspinal cross-sectional area and patient-reported outcomes after ACDF are necessary to lend greater strength to this recommendation. LEVEL OF EVIDENCE: Level III, diagnostic study.

Paraspinal Muscle Contractile Function is Impaired in the ENT1-deficient Mouse Model of Progressive Spine Pathology.

STUDY DESIGN: Basic science study of the relationship between spine pathology and the contractile ability of the surrounding muscles. OBJECTIVE: The aim of this study was to investigate single muscle fiber contractile function in a model of progressive spine mineralization (ENT1-/- mice). SUMMARY OF BACKGROUND DATA: Altered muscle structure and function have been associated with various spine pathologies; however, studies to date have provided limited insight into the fundamental ability of spine muscles to actively contract and generate force, and how this may change in response to spine pathology. METHODS: Experiments were performed on two groups (ENT1-/- [KO] and ENT1+/+ [WT]) of mice at 8 months of age (n = 12 mice/group). Single muscle fibers were isolated from lumbar multifidus and erector spinae, as well as tibialis anterior (a non-spine-related control) and tested to determine their active contractile characteristics. RESULTS: The multifidus demonstrated decreases in specific force (type IIax fibers: 36% decrease; type IIb fibers: 29% decrease), active modulus (type IIax: 35% decrease; type IIb: 30% decrease), and unloaded shortening velocity (Vo) (type IIax: 31% decrease) in the ENT1-/- group when compared to WT controls. The erector spinae specific force was reduced in the ENT1-/- mice when compared to WT (type IIax: 29% decrease), but active modulus and Vo were unchanged. There were no differences in any of the active contractile properties of the lower limb TA muscle, validating that impairments observed in the spine muscles were specific to the underlying spine pathology and not the global loss of ENT1. CONCLUSION: These results provide the first direct evidence of cellular level impairments in the active contractile force generating properties of spine muscles in response to chronic spine pathology.Level of Evidence: N/A.

The effect of paraspinal muscle on functional status and recovery in patients with lumbar spinal stenosis.

PURPOSE: To investigate the association of paraspinal muscle quantity and quality with functional status in patients with lumbar spinal stenosis (LSS) and explore whether degeneration of paraspinal muscle could predict patients' functional recovery. METHODS: The data of 69 patients (26 males, 43 females; mean age 60.6 ± 9.4 years) with LSS was reviewed. The total cross-sectional area (tCSA), functional cross-sectional area (fCSA), and fatty infiltration (FI) of paraspinal muscle were measured. The Oswestry Disability Index (ODI) scores were used to reflect patients' functional status. Correlations between measurements of paraspinal muscle and ODI scores were investigated by the Pearson correlation analysis. The multiple linear regression analysis was used to explore the correlation between change of ODI and other potential influence factors. Receiver operating characteristic curve was used to find out the most optimum cut-off value for predicting functional recovery. RESULTS: The pre-operation ODI was significantly associated with multifidus muscle (MF) fCSA (r = - 0.304, p = 0.012), while the post-operation ODI was significantly correlated to MF FI (r = 0.407, p < 0.01). Preoperative MF FI was an independent influence factor for change of ODI. The best cut-off value of preoperative MF FI to predict improvement of functional status (change of ODI > 50%) was 33%. CONCLUSION: The preoperative degeneration of MF was significantly associated with patients' functional status. Preoperative MF FI was a good predictor for assessing improvement of patients' functional status. Evaluation of paraspinal muscle before operation could be helpful for surgeons to predict patients' functional status and recovery.

Evaluation of persons with suspected lumbosacral and cervical radiculopathy: Electrodiagnostic assessment and implications for treatment and outcomes (Part II).

The electrodiagnostic (EDX) examination with needle electromyography (EMG) is the most important means of testing for radiculopathy. This test has modest sensitivity but high specificity and complements imaging of the spine. In this second of a two-part review, the implications of electrodiagnostic findings for diagnosis and clinical management of persons with radiculopathy are reviewed. An EMG confirmed lumbosacral radiculopathy is associated with better clinical outcomes for persons undergoing aggressive conservative management. A positive EMG test portends a better clinical response to epidural corticosteroid injections. If a person undergoes spine surgery, a positive pre-operative EMG for radiculopathy is also associated with better outcomes.

Sharp lower back pain • left-side paraspinal tenderness • anterior thigh sensory loss • Dx?

► Acute-onset, sharp nonradiating lower back pain ► Left-side paraspinal tenderness ► Anterior thigh sensory loss.

A model for evaluation of the electric activity and oxygenation in the erector spinae muscle during isometric loading adapted for spine patients.

BACKGROUND: Simultaneous measurement of electromyography (EMG) and local muscle oxygenation is proposed in an isometric loading model adjusted for patients that have undergone spinal surgery. METHODS: Twelve patients with degenerative lumbar spinal stenosis (DLSS) were included. They were subjected to a test protocol before and after surgery. The protocol consisted of two parts, a dynamic and an isometric Ito loading with a time frame of 60 s and accompanying rest of 120 s. The Ito test was repeated three times. EMG was measured bilaterally at the L4 level and L2 and was recorded using surface electrodes and collected (Biopac Systems Inc.). EMG signal was expressed as RMS and median frequency (MF). Muscle tissue oxygen saturation (MrSO2) was monitored using a near-infrared spectroscopy (NIRS) device (INVOS® 5100C Oxymeter). Two NIRS sensors were positioned bilaterally at the L4 level. The intensity of the leg and back pain and perceived exertion before, during, and after the test was evaluated with a visual analogue scale (VAS) and Borg RPE-scale, respectively. RESULTS: All patients were able to perform and complete the test protocol pre- and postoperatively. A consistency of lower median and range values was noted in the sensors of EMG1 (15.3 µV, range 4.5-30.7 µV) and EMG2 (13.6 µV, range 4.0-46.5 µV) that were positioned lateral to NIRS sensors at L4 compared with EMG3 (18.9 µV, range 6.5-50.0 µV) and EMG4 (20.4 µV, range 7.5-49.0 µV) at L2. Right and left side of the erector spinae exhibited a similar electrical activity behaviour over time during Ito test (60 s). Regional MrSO2 decreased over time during loading and returned to the baseline level during recovery on both left and right side. Both low back and leg pain was significantly reduced postoperatively. CONCLUSION: Simultaneous measurement of surface EMG and NIRS seems to be a promising tool for objective assessment of paraspinal muscle function in terms of muscular activity and local muscle oxygenation changes in response to isometric trunk extension in patients that have undergone laminectomy for spinal stenosis.

Paraspinal muscle changes after single-level posterior lumbar fusion: volumetric analyses and literature review.

BACKGROUND: Posterior lumbar fusion is a widely accepted surgical technique; however, it has been related to the possibility of paraspinal muscle atrophy after surgery. We investigated 1-year postoperative changes in paraspinal muscle volume using a simple formula applicable to magnetic resonance imaging (MRI) or computed tomography (CT) images. METHODS: Patients with degenerative lumbar spinal stenosis who underwent posterior interbody fusion (PLIF) at the L4/5 level in the period from May 2010 to June 2017 were enrolled in this study. Radiologic parameters were measured using MRI or CT images which were taken before surgery and at 1 year after surgery. The volume of the paraspinal muscles was calculated using a simple formula which was derived from the formula for calculating the volume of truncated elliptic cones. RESULTS: A total of 40 patients were included; 24 were analyzed using MRI and 16 were analyzed using CT. The mean age of the patients was 59.6 ± 12.1 years and 32 (80.5%) were female. When comparing the preoperative and 1-year-postoperative images, multifidus muscle (MF) reduction was consistently observed in the MRI and CT groups, right and left (p = 0.003, p < 0.001, p = 0.005 and p < 0.001, respectively). In the erector spinae (ES) group, decrease in muscle volume was observed in the right-sided muscles of the CT group (p < 0.001), but no significant change was observed in the MRI group. The psoas muscle showed no significant change after 1 year. Conversely, regression analysis showed a negative correlation between MF muscle volume loss and age in the MRI group (right and left, p = 0.002 and p = 0.015, respectively), that is, the younger the age, the greater loss of muscle mass. CONCLUSION: After the posterior lumbar fusion, the volume of the MF muscles was markedly decreased, and the degree of decrease was apparent in the MRI. The volume of the ES muscles, which are located relatively laterally, also tended to decrease at 1 year after surgery.

Severity of degenerative lumbar spinal stenosis affects pelvic rigidity during walking.

BACKGROUND CONTEXT: To understand the role of compensation mechanisms in the development and treatment of symptomatic degenerative lumbar spinal stenosis (DLSS), pelvic stability during walking should be objectively assessed in the context of clinical parameters. PURPOSE: To determine the association among duration of symptoms, lumbar muscle atrophy, disease severity, pelvic stability during walking, and surgical outcome in patients with DLSS scheduled for decompression surgery. STUDY DESIGN/SETTING: Prospective observational study with intervention. PATIENT SAMPLE: Patients with symptomatic DLSS. OUTCOME MEASURES: Oswestry Disability Index score; duration of symptoms; lumbar muscle atrophy; severity grade; pelvis rigidity during walking. METHODS: Patients with symptomatic DLSS were analyzed on the day before surgery and 10 weeks and 12 months postoperatively. Duration of symptoms was categorized as: <2years, <5years, and >5years. Muscle atrophy at the stenosis level was categorized according to Goutallier. Bilateral cross-sectional areas of the erector spinae and psoas muscles were quantified from magnetic resonance imaging. Stenosis grade was assessed using the Schizas classification. Pelvic tilt was measured in standing radiographs. Pelvic rigidity during walking was assessed as root mean square of the pelvic acceleration in each direction (anteroposterior, mediolateral, and vertical) normalized to walking speed measured using an inertial sensor attached to the skin between the posterior superior iliac spine. RESULTS: Body mass index but not duration of symptoms, lumbar muscle atrophy, pelvic rigidity, and stenosis grade explained changes in Oswestry Disability Index from before to after surgery. Patients with greater stenosis grade had greater pelvic rigidity during walking. Lumbar muscle atrophy did not correlate with pelvic rigidity during walking. Patients with lower stenosis grade had greater muscle atrophy and patients with smaller erector spinae and psoas muscle cross-sectional areas had a greater pelvis tilt. CONCLUSIONS: Greater pelvic rigidity during walking may represent a compensatory mechanism of adopting a protective body position to keep the spinal canal more open during walking and hence reduce pain. Pelvic rigidity during walking may be a useful screening parameter for identifying early compensating mechanisms. Whether it can be used as a parameter for personalized treatment planning or outcome prognosis necessitates further evaluation.

Impact of Multifidus Muscle Swelling on C5 Palsy After Cervical Laminoplasty.

STUDY DESIGN: Retrospective radiological analysis OBJECTIVE.: The aim of this study was to identify the effects of posterior cervical muscle swelling on C5 palsy (C5P) by evaluating early postoperative magnetic resonance (MR) images. SUMMARY OF BACKGROUND DATA: Cervical laminoplasty is an established technique, but the risk of C5P after surgery has not been fully resolved. Studies have reported that lateral stretching and postoperative swelling of the multifidus muscle may cause stretching of the medial branches and cervical nerves. METHODS: A total of 214 C5 nerves of 107 consecutive patients who underwent laminoplasty were examined. We reviewed their demographic and surgical data and radiographic and MR images as parameters, including the axial cross-sectional area (CSA) of the posterior muscles. The patients and C5 nerves were divided into C5P and non-C5P groups. The parameters and changes were compared between the two groups to examine correlations with C5P. RESULTS: In demographic data, age, sex, history of smoking, diabetes mellitus, and preoperative Japanese Orthopedic Association scores were not significantly different between the groups. Only body mass index (BMI) was significantly higher in the C5P group. Regarding the surgical and imaging data, the number of laminoplasty, operative time, decompression trough width, cervical sagittal alignment, preoperative spinal cord rotation, and posterior shift of the spinal cord were not significantly different, but the multifidus CSA change ratio was significantly higher in the C5P group. Multiple logistic regression analyses revealed that the multifidus CSA change ratio and BMI were significant independent factors. CONCLUSION: Multifidus swelling is associated with C5P, possibly through traction of the C5 nerve via the medial branches of the cervical dorsal rami. The medial branch is the shortest of the dorsal rami and may have the largest effect by traction force. Therefore, a gentle maneuver of the deep posterior muscles during surgery is a potential countermeasure to prevent C5P. LEVEL OF EVIDENCE: 3.

The correlation analysis between sagittal alignment and cross-sectional area of paraspinal muscle in patients with lumbar spinal stenosis and degenerative spondylolisthesis.

BACKGROUND: The relationship between spinal alignment and skeletal muscle mass (SMM) has attracted attention in recent years. Sagittal alignment is known to deteriorate with age, but it is not known whether this is related to paraspinal muscles. Therefore, the purpose of this study is to elucidate the role of the multifidus (MF) and psoas major (PS) muscles in maintaining global spinal alignment in patients with lumbar spinal stenosis (LSS) and/or degenerative spondylolisthesis (DS), and to analyze whether each muscles' cross-sectional area (CSA) correlates with whole-body SMM using bioimpedance analysis (BIA). METHODS: We retrospectively evaluated 140 patients who were hospitalized for surgery to treat LSS and/or DS. Spinal alignment, CSA of spinal muscles, and body composition parameters were measured from full-length standing whole-spine radiography, MRI, and BIA before surgery. The following standard measurements were obtained from radiographs: sagittal balance (C7-SVA), cervical lordosis (CL; C2-C7), lumbar lordosis (LL; L1-S1), thoracic kyphosis (TK; T5-T12), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). RESULTS: The average PS CSA (AveCSA) was highest at L4-L5, whereas MF AveCSA was highest at L5-S1. Paraspinal muscle CSAs were greater in males than in females. There was no statistically significant difference between the left and right CSA for either MF or PS. Correlation coefficient showed strong correlations between the PS AveCSA (L4-L5) and whole body SMM (r = 0.739). Correlation coefficient analysis also showed weak correlation between SMM and PT (r = - 0.184). Furthermore, PS AveCSA (L4-L5) correlated with the PT (r = - 0.183) and age (r = - 0.156), while PT correlated with the whole body SMM (r = - 0.184) but not with age. CONCLUSIONS: Whole body SMM showed correlation with PS AvCSA (L4-L5) and with PT among the spinal parameters, which was the same result in MF AvCSA (L4-L5). These findings suggest that the posterior inclination of the pelvis may be correlated with paraspinal muscle area rather than age.

The erector spinae plane block for effective analgesia after lung lobectomy: Three cases report.

RATIONALE: The thoracic epidural block and thoracic paravertebral block are widely used techniques for multimodal analgesia after thoracic surgery. However, they have several adverse effects, and are not technically easy. Recently, the erector spinae plane block (ESPB), an injected local anesthetic deep to the erector spinae muscle, is a relatively simple and safe technique. PATIENT CONCERNS: Three patients were scheduled for video assisted thoracoscopic lobectomy with mediastinal lymph node dissection. All the patients denied any past medical history to be noted. DIAGNOSES: They were diagnosed with primary adenocarcinoma requiring lobectomy of lung. INTERVENTIONS: The continuous ESPB was performed at the level of the T5 transverse process. The patient was received the multimodal analgesia consisted of oral celecoxib 200 mg twice daily, intravenous patient-controlled analgesia (Fentanyl 700 mcg, ketorolac 180 mg, total volume 100 ml), and local anesthetic (0.375% ropivacaine 30 ml with epinephrine 1:200000) injection via indwelling catheter every 12 hours for 5 days. Additionally, we injected a mixture of ropivacaine and contrast through the indwelling catheter for verifying effect of ESPB and performed Computed tomography 30 minutes later. OUTCOMES: The pain score was maintained below 3 points for postoperative 5 days, and no additional rescue analgesics were administered during this period. In the computed tomography, the contrast spread laterally from T2-T12 deep to the erector spinae muscle. On coronal view, the contrast spread to the costotransverse ligament connecting the rib and the transverse process. In the 3D reconstruction, the contrast spread from T6-T10 to the costotransverse foramen. LESSONS: Our contrast imaging data provides valuable information about mechanism of ESPB from a living patient, and our report shows that ESPB can be a good option as a multimodal analgesia after lung lobectomy.

Sarcopenia does not affect clinical outcomes following lumbar fusion.

Sarcopenia, defined as decreased skeletal muscle mass or function, has recently been found to have increased perioperative morbidity and mortality. The relationship between sarcopenia and clinical outcomes in patients undergoing lumbar fusion has not been examined. This study investigates whether sarcopenia affects fusion rates and outcomes following single-level lumbar decompression and fusion. A retrospective analysis was undertaken of 97 consecutive patients who underwent a single level lumbar fusion for degenerative spondylolisthesis. Demographics, perioperative data, and patient reported clinical outcomes were collected. Measurements of paraspinal muscle CSA were made using a standardized protocol at the level of the L3-4 disc space on a preoperative lumbar MRI. Univariate analysis was used to compare cohorts with regards to demographics, comorbidities, and clinical outcomes. Of 97 patients, 16 patients (15.8%) were in the sarcopenic cohort utilizing a threshold of 986.1 mm2/m2. Reoperation rates were not significantly different between the two groups (0% vs 3.6%, p = .451). The sarcopenia cohort had lower BMI (28.1 vs 31.8, p = .017) and less male patients (6.3% vs 55.6%, p < .001). Mean follow-up was 18.3 months. There was no significant difference in postoperative Oswestry Disability Index (ODI) (24.7 vs 23.2, p = .794) Short Form 12 Physical (38.0 vs. 40.4, p = .445) Mental scores (55.5 vs. 53.6, p = .503), or visual analog scale (VAS) back pain scores (3.4 vs. 3.3, p = .818). No significant difference was found with regards to outcomes when comparing sarcopenic to non-sarcopenic patients undergoing lumbar fusion. Sarcopenia does not impact the clinical success of lumbar fusion for degenerative spondylolisthesis.

Botulinum toxin for Pisa syndrome: An MRI-, ultrasound- and electromyography-guided pilot study.

INTRODUCTION: Pisa syndrome is a disabling, medication-resistant, postural abnormality that may affect 7-10% of patients with Parkinson's disease. In this study, we sought to assess the efficacy of botulinum toxin injections in Parkinson's disease-associated Pisa syndrome using a Magnetic Resonance Imaging-, Ultrasonography-, and Electromyography-guided combined approach. METHODS: We conducted a pilot study to evaluate the efficacy of botulinum toxin type-A injection in paraspinal and non-paraspinal axial muscles after a Magnetic Resonance Imaging and ultrasound-guided electromyography evaluation. Inclusion criteria were Pisa syndrome, idiopathic Parkinson's disease, and stable dopaminergic medications. Exclusion criteria were previous treatment with botulinum toxin, history of major spine surgery, and severe orthopedic diseases. As primary endpoint, we measured the rate of patients improving by at least 5° in the lateral trunk flexion 2 months after therapy. Secondary endpoints were the extent of lateral trunk flexion improvement, and changes in PS-associated pain/discomfort, measured by the Visual Analogue Scale. RESULTS: Out the 15 patients initially enrolled, 13 completed the follow-up assessment, while 2 joined a rehabilitation program and were excluded from the analyses. The rate of responders was 84.6% (n = 11/13), with 40% average reduction in trunk bending. Pain/discomfort improved in all patients, with 52.2% amelioration at the Visual Analogue Scale. The procedure was well tolerated in all cases, without side effects or complications. CONCLUSION: A combined imaging and EMG botulinum toxin approach to Pisa syndrome may yield a success rate greater than 80% in Parkinson's disease.

The Effect of Paravertebral Muscle on the Maintenance of Upright Posture in Patients With Adult Spinal Deformity.

OBJECTIVE: We investigated the relationship between cross-sectional area (CSA) of paravertebral muscle and trunk tilt at standing and walking in adult spinal deformity (ASD) surgery. SUMMARY OF BACKGROUND DATA: Although the importance of back muscles for the development of spinal kyphosis was well described, the influence on maintaining the sagittal balance was unclear. METHODS: Forty-five female patients (mean age, 68.8 years) with ASD were studied. We measured sagittal vertical axis [SVA], pelvic tilt [PT], and pelvic incidence-lumbar lordosis [PI-LL]) by lateral spine radiograph. For the assessment of trunk tilt standing-trunk tilt angle (STA) by lateral standing radiograph, gait-trunk tilt angle (GTA) by lateral gait images, and the increasing trunk tilt angle (ITA) by subtracting the STA from the GTA were calculated. Using L1/2 and L4/5 axial MRI, the CSAs of bilateral multifidus muscles (MF) and elector spinae (ES) removed fat by Image J software were calculated. We examined the correlation between trunk tilt angle (STA, GTA, and ITA) and spinopelvic parameters (SVA, PT, and PI minus LL) and also the correlation among muscle CSA, trunk tilt angle (STA, GTA, and ITA), and Oswestry Disability Index (ODI). RESULTS: The mean STA, GTA, and ITA were 4.2°, 13.0°, and 8.8°, respectively. The CSAs of back muscles were 278 mm2 at L1/2 MF, 1,687 mm2 at L1/2 ES, 636 mm2 at L4/5 MF, and 1,355 mm2 at L4/5 ES, respectively. Trunk tilt angle had significant relations with spinopelvic parameters. Concerning about muscle CSA, significant correlations were observed between STA and L4/5 MF (r = -0.517), GTA and L1/2 ES (r = -0.461) and L4/5 MF (r = -0.476), and ITA and L1/2 ES(r = -0.429). ODI showed significant correlation with STA and GTA. CONCLUSIONS: Paravertebral muscles were crucial to keep upright posture during walking as well as standing.

Dysregulation of the Inflammatory Mediators in the Multifidus Muscle After Spontaneous Intervertebral Disc Degeneration SPARC-null Mice is Ameliorated by Physical Activity.

STUDY DESIGN: A longitudinal case-control animal model. OBJECTIVE: The aim of this study was to investigate the inflammatory pathways active in the multifidus muscle after spontaneous intervertebral disc degeneration (IDD), and whether these IDD-related muscle changes can be ameliorated by exercise. SUMMARY OF BACKGROUND DATA: A pro-inflammatory response is present in the multifidus muscle after an intervertebral disc lesion and has been proposed to drive the structural alterations present during low back pain. However, it is not known whether spontaneous IDD produces an inflammatory response. Furthermore, exercise/physical activity produces a strong anti-inflammatory response, but its effectiveness in ameliorating inflammation in the multifidus is unknown. We assessed the inflammatory profile of the multifidus and the effectiveness of physical activity as a treatment using an animal model of spontaneous model of IDD. METHODS: Wild-type and SPARC null mice that were sedentary or housed with a running wheel were used in this study. Multifidus muscle segments were harvested from L2-L6 from the mice at 9 months of age after they had undergone a magnetic resonance imaging (MRI) scan to determine levels with IDD. The inflammatory profile of the multifidus was examined using quantitative polymerase chain reaction (PCR) assays. RESULTS: Spontaneous IDD in the SPARC-null mice caused a dysregulation of interleukin (IL)-1ß, IL6, transforming growth factor-beta (TGFß1), and adiponectin expression. More specifically, the proximity and degree of IDD was related to levels of IL-1ß expression. Physical activity reduced the pro-inflammatory response to IDD in the multifidus. IL-1ß, tumor necrosis factor (TNF), IL-10, adiponectin, and leptin levels were lower in the physically active group. CONCLUSION: These results reveal that spontaneous IDD causes dysregulation of the inflammatory pathways active in the multifidus muscle. These alterations were related to the severity of IDD and were prevented by physical activity. LEVEL OF EVIDENCE: N/A.

Ultrasound guided erector spinae plane block as a cause of unintended motor block. / Bloqueo en el plano del erector de la columna ecoguiado como causa de bloqueo motor imprevisto.

Erector spinae plane block (ESPB) as postoperative analgesia method has been successfully carried out in several surgical interventions. Postoperative pain treatment for cesarean section is considered one of the important challenges for anesthesiologists due to the risk of chronic pain development and even pospartum depression. Regional anesthesia techniques were effectively used to prevent the pain together with multimodal analgesia regimes in cesarean section. Formerly, successful erector spinae plane block was documented as postoperative analgesia treatment for cesarean section; however, no motor weakness was recorded as a side effect. In this case report, we present an unexpected motor weakness as a side effect of the erector spinae plane block after cesarean delivery operation in a 29 year old patient. To our knowledge, this is the first report of motor weakness related to the ESPB.