Muscle Fatty Degeneration Research Articles

ID: 216055 Ultrasound-Guided Peripheral Nerve Stimulation for Shoulder Pain: Suprascapular Versus Axillary Nerve

A 59-year-old woman presented with severely debilitating right shoulder pain. Her MRI C-spine showed large right paracentral disc extrusion at C5-C6 mildly compressing on the cervical cord. MRI of her right shoulder was significant for a full-thickness tear of her supraspinatus-infraspinatus with moderate muscle atrophy and fatty degeneration. The patient worked on an assembly line where she had to perform a consistent overhead motion which exacerbated her shoulder pain.

Axial Postural Abnormalities in Parkinsonism: Gaps in Predictors, Pathophysiology, and Management.

Axial Postural Abnormalities in Parkinsonism: Gaps in Predictors, Pathophysiology, and Management.

Risk factors for residual back pain following percutaneous vertebral augmentation: the importance of paraspinal muscle fatty degeneration

PurposeResidual back pain (RBP) after percutaneous vertebral augmentation (PVA) still exists considerable, and it even affects daily life due to moderate or severe back pain. A variety of risk factors have been previously identified for developing residual back pain. However, there are conflicting reports regarding the association between sarcopenia and residual back pain. As such, the aim of this study was to investigate whether paraspinal muscle fatty degeneration is a predictor of residual back pain.MethodsWe retrospectively reviewed the medical records of patients with single-segment OVCF who underwent PVA from January 2016 to January 2022. Patients were divided into RBP group (86 patients) and control group (790 patients) according to whether the visual analog scale (VAS) score ≥ 4. The clinical and radiological data were analyzed. Paraspinal musculature fatty degeneration was measured using the Goutallier classification system (GCS) at the L4 − 5 intervertebral disc level. Univariate and multivariate logistic regression analyses were performed to identify risk factors.ResultsThe results of multivariate logistical regression analysis revealed that posterior fascia injury (odds ratio (OR) = 5.23; 95% confidence interval (CI) 3.12–5.50; P < 0.001), as regards paraspinal muscle fatty degeneration, including Goutallier grading (OR = 12.23; 95% CI 7.81–23.41; P < 0.001), fCSA (OR = 3.06; 95% CI 1.63–6.84; P = 0.002), fCSA/CSA (%) (OR = 14.38; 95% CI 8.80–26.29; P < 0.001), and facet joint violation (OR = 8.54; 95% CI 6.35–15.71; P < 0.001) were identified as independent risk factors for RBP.ConclusionsPosterior fascia injury, paraspinal muscle fatty degeneration, and facet joint violation were identified as independent risk factors for RBP, with paraspinal muscle fatty degeneration playing an important role.

Prognostic Factors for Clinical Outcomes After Arthroscopic Rotator Cuff Repair.

Limited knowledge exists regarding prognostic factors after rotator cuff repair. To identify pre- and perioperative predictors for functional outcomes after arthroscopic rotator cuff repair. Case-control study; Level of evidence, 3. This study included patients who underwent arthroscopic rotator cuff repair between January 2013 and April 2019 and who had preoperative magnetic resonance imaging scans. The procedures were performed by 4 shoulder surgeons at a single institution. Excluded were patients who had previous surgeries, those who underwent open surgery, and those without 12- and 24-month follow-up clinical data. Patient-reported outcomes (American Shoulder and Elbow Surgeons [ASES] Standardized Shoulder Assessment Form and University of California, Los Angeles [UCLA] Shoulder Rating Scale scores) were assessed preoperatively and at 6, 12, and 24 months postoperatively. Using multiple linear regression analysis, the authors evaluated the influence of 29 variables relating to patient, lesion, and procedure characteristics on postoperative outcomes, with the 24-month ASES score as the dependent variable. The study sample consisted of 474 patients (500 shoulders). The median ASES score increased from 41.6 preoperatively to 88.3 at 24 months (P < .001), and the median UCLA score increased from 14 preoperatively to 32 in the same period (P < .001). The following variables were found to be independent predictors for higher 24-month postoperative ASES score: male sex, absence of rheumatologic disease, older age, lower degree of supraspinatus muscle fatty degeneration, acromioplasty, and a higher preoperative ASES score. The prognostic factors for better clinical results at 24 months after arthroscopic rotator cuff repair were male sex, absence of rheumatologic disease, older age, lower degree of fatty degeneration of the supraspinatus muscle, concomitant acromioplasty, and higher preoperative ASES score.

Development of a Rabbit Chronic-Like Rotator Cuff Injury Model for Study of Fibrosis and Muscular Fatty Degeneration

Rabbit rotator cuff (RC) pathophysiology can lead to progressive and highly degenerative changes in its associated musculature and tendons, which negatively influences clinically relevant parameters, such as strength and retraction of the muscle-tendon/myotendinous unit, ultimately causing loss of shoulder function and negatively affecting RC repair outcomes. Animal models that mimic aspects of human RC anatomy and pathophysiology are crucial for advancing the conceptual understanding of injury progression and developing effective tissue engineering and regenerative medicine-based therapeutics. Within this context, a rabbit subscapularis (SSC) model is suitable due to (i) its anatomical similarity to the human supraspinatus (SSP) bone-tendon-muscle unit, which is the most frequently injured RC site; (ii) its pathophysiological similarity to humans in terms of fibrosis and muscle fatty degeneration (FD); and (iii) its amenability to surgical procedures. Therefore, the goal of this study is to describe the surgical techniques for inducing SSC RC injury. Briefly, the procedure involves the isolation of the SSC by identifying the coracobrachialis muscle followed by a full-thickness transection at the muscle-tendon junction and wrapping the free end of the muscle-tendon junction with a silicone-based penrose tubing to prevent spontaneous reattachment. Histologic evaluations are performed to monitor the progression of muscle FD at 4 weeks post-surgery using hematoxylin and eosin (H&E) as well as Masson's trichrome staining. Loss of muscle and FD were evident 4 weeks after transection of the SSC muscle-tendon junction, similar to human RC pathophysiological conditions. This protocol demonstrates the steps for successfully establishing a chronic-like rabbit SSC RC injury model, which can serve as a powerful tool to study skeletal muscle changes associated with RC pathophysiology and aid the development of novel therapeutic strategies for chronic-like RC tears.

Significance of paraspinal muscle quality in risk between single and multiple osteoporotic vertebral fractures.

To compare paraspinal muscle quality between patients with single and multiple osteoporotic vertebral fractures (OVFs) and evaluate the role of the paraspinal muscles in OVFs. A total of 262 consecutive patients with OVFs were retrospectively analyzed in two groups: those with single OVF (n = 173) and those with multiple OVFs (n = 89). The cross-sectional area (CSA) and fatty degeneration of the paraspinal muscles were calculated from axial T2-weighted magnetic resonance imaging at the level of the L4 upper endplate by manual tracing in ImageJ software. Pearson's correlation analysis was performed to analyze correlations of paraspinal muscle quality to multiple OVFs. FD in all the paraspinal muscles was significantly higher in the multiple OVF group than the single OVF group (all p < 0.005). The functional CSA (fCSA) of the paraspinal muscles was significantly lower in the multiple OVF group than the single OVF group (all Ps < 0.001), except for the erector spine (p = 0.304). The Pearson's correlation analysis showed significant positive inter-correlations for the fCSAs of all the paraspinal muscles and the occurrence of multiple OVFs. The pure muscle volumes of the multifidus, psoas major, and quadratus lumborum were lower in patients with multiple OVFs than in those with a single OVF. Furthermore, the inter-correlation among all the paraspinal muscles indicate that the muscle-bone crosstalk profoundly existed in vertebral fracture cascade. Therefore, special attention to paraspinal muscle quality is needed to prevent progression to multiple OVFs.

Correlation between inflammatory cytokine expression in paraspinal tissues and severity of disc degeneration in individuals with lumbar disc herniation

PurposePrevious animal studies have discovered dysregulation of the local inflammatory state as a novel mechanism to explain structural changes in paraspinal muscles in association with disc degeneration. This study aimed to determine whether the expression of inflammatory genes in the multifidus muscle (MM) differs between individuals with disc degeneration and non-degeneration, which may cause changes in the cross-sectional area (CSA) of paraspinal muscles and clinical outcomes.MethodsMuscles were procured from 60 individuals undergoing percutaneous endoscopic lumbar discectomy for lumbar disc herniation (LDH). Total and functional CSAs and fatty degeneration of paraspinal muscles on ipsilateral and unilateral sides were measured. Gene expression was quantified using qPCR assays. Paired t-test and Pearson’s correlation analysis were used to compare the mean difference and associations, respectively.ResultsThere were significant differences in total CSAs of paraspinal muscles and functional CSA and fatty degeneration of MM between ipsilateral and unilateral sides. Participants in the disc degeneration group displayed higher fat infiltration in MM. The expression of TNF was moderately correlated with total CSAs of paraspinal muscles and functional CSA and fatty degeneration of MM. The expression of IL-1β was strongly correlated with the total and functional CSA of MM. The expression of TGF-β1 was moderately correlated with the functional CSA of MM. The expression of TNF, IL-1β, and TGF-β1 was moderate to strongly correlated with clinical outcomes.ConclusionThe results show that there were differences in the characteristics of paraspinal muscles between the ipsilateral and unilateral sides, which were affected by disc degeneration and the degree of fat infiltration. High-fat filtration and reduction of CSA of MM are associated with inflammatory dysfunction. There was evidence of a dysregulated inflammatory profile in MM in individuals with poor clinical outcomes.

Paper 18: Minimum 10-year follow-up of arthroscopic superior capsule reconstruction for irreparable rotator cuff tears: Graft survival rate and progression of cuff tear arthropathy

Objectives: Superior capsule reconstruction (SCR) was developed as an alternative treatment for irreparable rotator cuff tears. Previous studies showed graft healing is key to improve shoulder function and pain relief after SCR. Graft healing rate after SCR have been reported for irreparable rotator cuff tears in short-term follow-up studies. The objective of this study was to assess graft survival rate and progression of cuff tear arthropathy in minimum 10-year follow-up of arthroscopic SCR. Methods: A total of 48 consecutive patients with 50 affected shoulders underwent SCR using fascia lata autograft for the treatment of irreparable rotator cuff tears by a single surgeon between 2007 to 2011. Of these 48 initially identified patients, 5 had died, 5 had moved and were unable to be contacted, 2 had severe health problems that were unrelated to SCR, 1 refused to participate, and 1 was unable to participate because she was caring for her child with terminal cancer, thus leaving 34 patients with 36 affected shoulders for review. Structural outcomes were evaluated for a minimum of 10 years of follow-up (range, 10–13 years). Acromiohumeral distance (AHD) and Hamada grade (stage of cuff tear arthropathy) were evaluated by using standard radiography. Fatty degeneration of the rotator cuff muscles was evaluated according to the Goutallier grading system. Graft healing and thickness were assessed by using T2-weighted MRI (1.5-T closed-type scanner). By using SYNAPSE software (accuracy, 0.05 mm; FUJIFILM Medical System, Loveland, CO), graft thickness at 1 cm posterior to the bicipital groove in the coronal plane of T2-weighted MRI was measured at the greater tuberosity side (medial aspect of the footprint on the greater tuberosity), at midgraft (top of the humeral head), and at the glenoid side (5 mm posterior to the articular surface on the glenoid). Results: Graft survival rate was 94% (34 of 36 shoulders) at 1 year after SCR, 92% (33 of 36 shoulders) at 2 to 4 years after SCR, and 89% (32 of 36 shoulders) at 5 to 10 years after SCR. Regarding the 30 patients (32 shoulders) whose grafts remained intact, graft thickness at 1 year after SCR was 8.1 ± 1.9 mm on the greater tuberosity, 6.8 ± 1.5 mm at midgraft, and 11.4 ± 2.0 mm on the glenoid. At 10 years after SCR, graft thickness (7.8 ± 1.6 mm on the greater tuberosity, 7.5 ± 1.8 mm at midgraft, 11.2 ± 2.2 mm on the glenoid) did not significantly differ from that at 1 year after SCR (P = 0.14 to 0.52). Although the rate of low intensity on T2 MRI of the grafts at 1 year after SCR was 53% (17 of 32 shoulders), all grafts had become low intensity on T2 MRI by 10 years after SCR (P &lt; 0.001). Compared with the preoperative measurement, AHD was increased significantly at 1, 5, and 10 years after SCR (P &lt; 0.001). Average AHD did not differ among 1, 5, and 10 years after SCR (P = 0.09 to 0.87). Because of the increase in AHD, the Hamada grade at 1, 5, and 10 years after SCR was significantly decreased (i.e., reduced cuff tear arthropathy) (P &lt; 0.001) compared with the preoperative grade. Before SCR, the AHD was significantly narrower and the Hamada grade was significantly higher in the affected shoulder compared with the unaffected shoulder. At 10 years after SCR, neither AHD nor Hamada grade differed significantly between the affected and unaffected shoulders (i.e., cuff tear arthropathy had not progressed during the 10 years or more after SCR) in patients with healed grafts, whereas all 4 of the remaining patients with postoperative graft tear showed increased cuff tear arthropathy to grade 4a or 4b. One patient with graft tear was converted to reverse shoulder arthroplasty. Conclusions: The graft survival rate at 10 years follow-up was 89%. Graft thickness was maintained at 10 years after SCR when graft was healed. Graft healing prevented progression of cuff tear arthropathy after arthroscopic SCR.

Serum Vitamin D Level Correlations With Tissue Vitamin D Level and Muscle Performance Before and After Rotator Cuff Repair

Background: There is a lack of studies about serum and tissue vitamin D levels of the rotator cuff muscle on muscle power, fatty degeneration, and healing failure after rotator cuff repair (RCR). Furthermore, no studies have evaluated vitamin D receptor proteins in the rotator cuff that show a close association with serum vitamin D levels. Purpose: To evaluate the correlations between serum vitamin D and tissue vitamin D as well as perioperative variables of arthroscopic RCR. Study Design: Case series; Level of evidence, 4. Methods: From March 2017 to October 2017, a total of 36 patients who underwent RCR were prospectively enrolled, and supraspinatus muscle tissue was obtained during surgery to analyze tissue vitamin D levels. Serum vitamin D levels were checked preoperatively and at 6 months and 1 year postoperatively. Tissue vitamin D levels were assessed using liquid chromatography, and the vitamin D receptor was measured by western blotting. Isokinetic muscle performance test (IMPT; peak torque and torque deficiency compared with the opposite shoulder) results and fatty degeneration of the rotator cuff using the Goutallier classification were assessed preoperatively and at 1 year after surgery. The American Shoulder and Elbow Surgeons score and Constant score were collected at 2 years after surgery. Healing failure of the repaired rotator cuff was analyzed by magnetic resonance imaging at 1 year after surgery. Results: Overall, only three patients (8.3%) had serum vitamin D sufficiency (>20 ng/mL). Among 36 patients, 26 patients returned for their 1-year follow-up. Lower preoperative serum vitamin D levels resulted in lower serum vitamin D levels at 6 months and 1 year postoperatively (all P < .05). Lower preoperative and 1-year postoperative serum vitamin D levels resulted in more torque deficiency on the IMPT in abduction than higher preoperative and 1-year postoperative serum vitamin D levels (all P < .05). Tissue vitamin D levels had a strong correlation with preoperative serum vitamin D levels (P = .001). Lower tissue vitamin D levels were associated with lower peak torque on the IMPT in abduction (P = .043) and a tendency of lower peak torque on the IMPT in external rotation (P = .077) at 1 year postoperatively. There was no correlation between tissue and serum vitamin D levels and functional outcomes, fatty degeneration, and healing failure after surgery (all P > .05). The vitamin D receptor showed no correlation with any variables (all P > .05). Conclusion: Lower preoperative serum vitamin D levels had a strong correlation with lower tissue vitamin D levels and lower serum vitamin D levels at 1 year after surgery. Furthermore, the patients with lower serum vitamin D levels showed more weakness of muscle power perioperatively. The results of this study emphasized the association between vitamin D levels and rotator cuff muscle power.

Junctional Kyphosis after Correction with Long Instrumentation for Late Posttraumatic Thoracolumbar Kyphosis: Characteristics and Risk Factors

Junctional kyphosis is a common complication after corrective long spinal fusion for adult spinal deformity. Whereas there is still a paucity of data on junctional kyphosis, specifically among late posttraumatic thoracolumbar kyphosis (LPTK) patients. Thus, the aim of this study was to investigate the characteristics and risk factors of junctional kyphosis in LPTK patients receiving long segmental instrumented fusion. We retrospectively reviewed a cohort of LPTK patients who had received long segmental instrumented fusion (>4 segments) in our center between January 2012 and January 2019. Radiographic assessments included the sagittal alignment, pelvic parameters, bone quality on CT images, and measurements of the cross-sectional area (CSA, cross-sectional area of muscle-vertebral body ratio × 100) and fat saturation fraction (FSF, cross-sectional area of fat-muscle body ratio × 100) of paraspinal muscles. Patients in this study were divided into those with junctional kyphosis or failure (Group J) and those without (Group NJ) during follow-up. Group J included patients with junctional kyphosis (Group JK) and patients with junctional failure (Group JF). A total of 65 patients (16 males and 49 females, average age 56.5 ± 23.4 years) were enrolled in this study. After (32.7 ± 8.5) months follow-up, 15 patients (23.1%) experienced junctional kyphosis, and four of them deteriorated into junctional failure. Eighty percent (12/15) of junctional kyphosis was identified within 6 months after surgery. In comparison with Group NJ, Group J were older (P=0.026), longer fusion levels (P < 0.001), greater thoracic kyphosis (P=0.01), greater global kyphosis (P=0.023), lower bone quality (P < 0.001), less CSA (P=0.005) and higher FSF (P <0.001) of paraspinal muscles. Preoperative global kyphosis more than 48.5° (P=0.001, odds ratio 1.793) and FSF more than 48.4 (P=0.010, odds ratio 2.916) were identified as independent risk factors of junctional kyphosis. Based on the statistical differences among Group NJ, Group JK and Group JF (P < 0.001), Group JF had lower bone quality than Group NJ (P < 0.001) and Group JK (P=0.015). In terms of patient-reported outcomes, patients in Group JF had worse outcomes in ODI and VAS scores, and PCS and MCS of SF-36 than Group NJ and group JK CONCLUSION: The prevalence of junctional kyphosis was 23.1% in LPTK patients after long segmental instrumented fusion. Preoperative hyperkyphosis and advanced fatty degeneration of paraspinal muscles were independent risk factors of junctional kyphosis. Patients with lower bone quality were more likely to develop junctional failure.

Risk factors for residual back pain following percutaneous cement augmentation: The importance of paraspinal muscle fatty degeneration

Risk factors for residual back pain following percutaneous cement augmentation: The importance of paraspinal muscle fatty degeneration

Artificial intelligence-based volumetric analysis of muscle atrophy and fatty degeneration in patients with hip osteoarthritis and its correlation with health-related quality of life

PurposeArtificial intelligence (AI) technologies have enabled precise three-dimensional analysis of individual muscles on computed tomography (CT) or magnetic resonance images via automatic segmentation. This study aimed to perform three-dimensional assessments of pelvic and thigh muscle atrophy and fatty degeneration in patients with unilateral hip osteoarthritis using CT and to evaluate the correlation with health-related quality of life (HRQoL).MethodsThe study included one man and 43 women. Six muscle groups were segmented, and the muscle atrophy ratio was calculated volumetrically. The degree of fatty degeneration was defined as the difference between the mean CT values (Hounsfield units [HU]) of the healthy and affected sides. HRQoL was evaluated using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index and the Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ).ResultsThe mean muscle atrophy rate was 16.3%, and the mean degree of muscle fatty degeneration was 7.9 HU. Multivariate correlation analysis revealed that the WOMAC stiffness subscale was significantly related to fatty degeneration of the hamstrings, the WOMAC physical function subscale was significantly related to fatty degeneration of the iliopsoas muscle, and the JHEQ movement subscale was significantly related to fatty degeneration of the hip adductors.ConclusionWe found that fatty degeneration of the hamstrings, iliopsoas, and hip adductor muscles was significantly related to HRQoL in patients with hip osteoarthritis. These findings suggest that these muscles should be targeted during conservative rehabilitation for HOA and perioperative rehabilitation for THA.

Humeral head coverage in arthroscopic partial repair of massive rotator cuff tears improves functional outcomes: an analysis of influential factors.

Although partial rotator cuff repair has shown good outcomes, differences in clinical outcomes remain concerns. This study was performed to determine whether patients with humeral head coverage would show better functional outcomes than patients without humeral head coverage and to identify the factors for humeral head coverage after arthroscopic partial repair of massive tears. We performed a retrospective study of 63 patients with massive rotator cuff tears who underwent arthroscopic partial repair between 2012 and 2018. Two to four margin convergences were first performed; then, the Mason-Allen technique was performed. The patients were divided into 2 groups: those with humeral head coverage (38 cases) and those without humeral head coverage (25 cases). The following factors were evaluated: age; sex; hypertension; diabetes; osteoporosis; preoperative and postoperative pseudoparalysis, visual analog scale (VAS) pain score, Constant score, acromiohumeral distance, and subacromial bony spur; and subscapularis tear and repair. Muscle atrophy and fatty degeneration were evaluated by magnetic resonance imaging preoperatively, and the integrity of the repaired cuff was evaluated by ultrasonography at a minimum of 2 years after surgery. Compared with preoperative values, significant improvements in VAS pain scores (from 6.27 to 2.32 in patients with humeral head coverage and from 7.00 to 2.81 in those without humeral head coverage) and Constant scores (from 51.35 to 75.95 and from 44.62 to 69.81, respectively) were observed in both groups (P<.001). Statistical analysis revealed that postoperative VAS pain scores (2.32 vs. 2.81) and Constant scores (75.95 vs. 69.81) in patients with humeral head coverage were superior to those in patients without humeral head coverage (P=.044 and P=.003, respectively). The integrity of the repaired cuff was evaluated by ultrasonography, and partial tears were found in 4 of 37 patients with humeral head coverage and 2 of 26 patients without humeral head coverage (P=.816). Univariable logistic regression analysis revealed that age (P<.001), comorbidity (P=.005), symptom duration (P=.023), preoperative shoulder mobility (P<.001), maintained acromiohumeral distance (P=.006), subscapularis tear (P=.026), and less preoperative supraspinatus and infraspinatus muscle atrophy (P=.001 and P=.010, respectively) had significant correlations with humeral head coverage. Overall satisfactory results were achieved in most patients regardless of high retear rates, but patients with partial repair covering the humeral head were associated with better outcomes than patients without humeral head coverage. Multivariable regression analysis revealed that age (<70 years, P=.003), capability of shoulder mobility (P=.005), maintenance of the acromiohumeral space (>7 mm, P=.016), and less atrophy of the rotator cuff muscles (P=.021) were favorable factors to achieve humeral head coverage during surgical partial repair of massive rotator cuff tears.

Analysis of Chronic Low Back Pain Caused by Lumbar Microinstability After Percutaneous Endoscopic Transforaminal Discectomy: A Retrospective Study.

ObjectiveChronic low back pain (CLBP) after percutaneous endoscopic transforaminal discectomy (PTED) surgery may be caused by preoperative lumbar microinstability (MI). However, there is a paucity of research on the relationship between lumbar microinstability and chronic low back pain. The purpose of this article is to assess the preoperative radiographic characteristics of patients and evaluate the effects of lumbar microinstability on patient-reported outcomes among single-level lumbar disc herniation (LDH) patients who underwent PTED.MethodsThis study retrospectively reviewed the radiographic characteristics of a consecutive series of 127 patients with low back pain and leg pain caused by single-level LDH underwent PTED from August 2018 to March 2021. They were divided into three groups according to the radiographic parameters: the stable group (Group S), the dysfunctional group (Group D), and the microinstability group (Group M). The visual analogue scale (VAS) scores for leg and low back pain and Oswestry Disability Index (ODI) were evaluated preoperatively and postoperatively. Logistic regression analysis was used to identify independent risk factors for CLBP.ResultsCompared with Group D and Group S, Group M had the highest ODI scores (P < 0.01) and VAS scores (low back pain) (P < 0.01) after 1 year, while there were no significant differences in the VAS scores for leg pain at different time points after surgery (P > 0.05). In addition, the logistic regression analysis results regarding CLBP revealed that muscle fatty degeneration on MRI (95% CI, 1.20–8.51, P = 0.02), and facet tropism (95% CI, 1.39 −11.37, P = 0.01) may be independent risk factors.ConclusionPatients with lumbar microinstability may have CLBP after PTED, so patients with lumbar microinstability may need to take internal fixation surgery to solve their symptoms.

Radiofrequency Neurotomy Does Not Cause Fatty Degeneration of the Lumbar Paraspinal Musculature in Patients with Chronic Lumbar Pain-A Retrospective 3D-Computer-Assisted MRI Analysis Using iSix Software.

The present study aimed (1) to analyze the relative paraspinal autochthonous intramuscular fat volume before and after radiofrequency neurotomy (RFN) and (2) to compare it to the contralateral non-treated side. Retrospective cohort study. Inselspital, University Hospital Bern, University of Bern. Twenty patients (59.60 ± 8.49 years; 55% female) with chronic low back pain, treated with RFN (L2/3-L5/S1) due to symptomatic facet joint syndrome (FCS) between 2008 and 2017 were included. All patients received a magnetic resonance imaging (MRI) of the lumbar spine before and at a minimum of 6 months after RFN. The absolute (cm3) and relative (%) paraspinal muscle and fat volume was analyzed three-dimensionally on standard T2-MRI sequences using a newly developed software (iSix, Osiris plugin). Both sides were examined and allocated as treated or non-treated side. A total of 31 treated and 9 non-treated sides (Level L2/3-L5/S1) were examined. There were no differences in the relative paraspinal intramuscular fat volume before and at a median of 1.4 [0.9 - 2.6] years after RFN (P = .726). We found no differences in the relative fat volume between the treated and non-treated side before (P = .481) and after (P = .578) RFN. Our study shows that there are no differences in the paraspinal muscle/fat distribution after RFN. RFN of the medial branches for FCS does not seem to cause fatty degeneration of the lumbar paraspinal muscles as a sign of iatrogenic muscle denervation.

The association of vertebral compression fracture progression with paraspinal muscle and psoas muscle degeneration

Objective: Few studies have investigated the relationship between spinal muscle fatty degeneration and vertebral compression fracture (VCF) progression. This study investigated the associations among spinal muscle fatty degeneration, functional support of the spinal muscles, and VCF progression.Methods: We retrospectively evaluated 49 consecutive elderly patients over 65 years of age who had VCFs between 2013 and 2020. Change in height loss was defined as the difference in height loss in vertebral collapse between the initial and &gt;6-month follow-up visits. Fatty infiltration of the paraspinal and psoas muscles was measured using T2-weighted magnetic resonance imaging at L3 and L4.Results: The VCF height loss change was 6.53±4.9 mm. The cross-sectional area of the paraspinal muscle was 2,418±496 mm2. The fatty infiltration rate of the paraspinal muscle was 4.46%±1.7%. Mild VCF height loss (a change o≤9 mm) was found in 36 patients (group 0), while severe height loss (a change &gt;9 mm) was observed in 13 patients (group 1). The paraspinal-to-psoas muscle ratio was 2.51 in group 0 and 3.33 in group 1 (P&lt;0.002). The paraspinal muscle mass (P&lt;0.02), bone mineral density (P&lt;0.05), and paraspinal-to-psoas muscle mass ratio (P&lt;0.01) affected VCF progression. The odds ratio of the paraspinal-to-psoas muscle ratio was 4.39.Conclusion: The paraspinal-to-psoas muscle ratio strongly influences VCF progression. In patients with VCF, progression can be predicted using the paraspinal-to-psoas muscle ratio before ambulation.

Arthroscopic Extreme Medialized Repair for Massive Rotator Cuff Tear: Resection of Cartilage and Subchondral Bone Over the Top of the Humeral Head

Rotator cuff repair is a widely performed surgery. Its purpose is to improve shoulder function, fix tendons to bones, restore anatomical structure, and prevent the progression of rotator cuff tear arthropathy and associated muscle degeneration. However, in large and massive tears, the tension imposed during repair becomes too high. Medialized repairs have been reported for cases of rotator cuff tear, but they are difficult to perform. We report on ex-medialization that used common portals and instruments to remove the osteochondral and subchondral bone, reduce humeral head volume, and suture the tendon extremely medially. Compared to a common medialized repair, this procedure reduces tension on the rotator cuff to be sutured. The goal of this technique is to restore functional anatomy, reduce the rate of retear, prevent the progression of rotator cuff muscle atrophy and fatty degeneration, and to improve muscle strength by allowing the repair of rotator cuff tears (Goutallier grade 2 or higher) to the humeral head, which have conventionally been challenging.

Temporal Tendinitis in Craniomandibular Dysfunction (CMD) - Does it Really Exist? A Temporomandibular MRI Investigation.

The aim of the study was to analyze the role of temporal muscle and particularly tendon pathology in patients suffering from craniomandibular dysfunction (CMD) using magnetic resonance imaging. Retrospective analysis of MRI examinations was carried out with regard to temporal muscle fibrosis and fatty degeneration and particularly temporal tendon rupture, thickening, and degenerative signal alterations. Descriptive statistics and the Mann-Whitney U-test were used for statistical evaluation. Structural lesions of temporal muscle parenchyma were the absolute exception. PD hyperintensity, pronounced contrast enhancement, or peritendinous fluid collections along the temporal tendon were found only to a small extent, and a (partial) rupture occurred in only one case. The tendon diameter showed only slight variability. The Mann-Whitney U-test provided no results indicating a causal connection between degenerative joint or disc disease and temporal tendon pathology. A large sample of 128 magnetic resonance imaging examinations provided no evidence of a major role of temporal tendinitis in clinical CMD syndrome. · Retrospective analysis of temporal tendon in CMD patients.. · Abnormal structural findings along the tendon seen only rarely.. · Obviously no crucial role of temporal tendon lesions in CMD syndrome.. · Stimmer H, Grill F, Waschulzik B et al. Temporal Tendinitis in Craniomandibular Dysfunction (CMD) - Does it Really Exist? A Temporomandibular MRI Investigation. Fortschr Röntgenstr 2022; 194: 1242 - 1249.

Longitudinal MR Quantification of the Fat Fraction within the Supraspinatus and Infraspinatus Muscles in Patients with Shoulder Pain

Knowing the natural history of fatty degeneration of rotator cuff muscles is important for estimating the risk and rate of progression to cuff tear arthropathy (CTA). The purpose of this study was to investigate the changes in rotator cuff muscle fatty degeneration over time quantitatively in patients treated conservatively for shoulder pain. Thirty patients with a baseline and follow-up shoulder MRI, including a 2-point Dixon sequence, which were performed at least 1 year apart, were included. We classified patients into 3 groups: "full-thickness tear" (n=7), "partial-thickness tear" (n=13), and "no-tear" (n=10) groups. The fat fraction in the supra- and infraspinatus muscles, and the rate of change in the fat fraction (ΔFfr) were calculated using the formula "fat fraction of follow-up MRI/fat fraction of initial MRI." We investigated the difference in ΔFfr among the 3 groups and the degree of progression to CTA. Statistically significant differences in ΔFfr within the supraspinatus and infraspinatus muscles were found among full-thickness, partial-thickness, and no-tear groups (2.54 vs 1.02 vs 0.75, p < 0.001 and 1.96 vs 1.07 vs 0.73, p=0.021, respectively). Overall, 71.4% of the full-thickness tear group showed progression of CTA, and 28.6% of the full-thickness tear group needed reverse shoulder arthroplasty within an average follow-up period of 34 months. MR quantification, together with the knowledge of change in fatty degeneration over time, may be useful for the management of patients with shoulder pain.

Primary Open Latarjet Procedure Results in Functional Differences but No Structural Changes in Subscapularis Muscle Quality vs the Healthy Contralateral Shoulder at Long-term Follow-up

Background: There are concerns that the Latarjet procedure results in loss of glenohumeral rotation and strength and in subscapularis dysfunction. The long-term effects of this procedure on subscapularis quality, glenohumeral rotation, and strength are unknown. Purpose/Hypothesis: To analyze the long-term effect of the primary open Latarjet procedure using a muscle-splitting approach on internal and external rotation and strength, as well as subscapularis muscle quality as compared with the healthy contralateral side. We hypothesized that the primary open Latarjet procedure is associated with a reduction of long-term shoulder strength and function and decreased subscapularis quality. Study Design: Case series; Level of evidence, 4. Methods: A total of 42 patients who underwent a primary open Latarjet procedure for recurrent anterior shoulder instability at a mean age of 26 years (range, 18-36) were reviewed after a mean follow-up of 8.4 years (range, 5-12). The subscapularis muscle volume and fat fraction of both shoulders were assessed. Bilateral active internal rotation (IR) and external rotation (ER), as well as IR and ER strength, were assessed by isokinetic testing (concentric, eccentric, and fatigability). Results: Active IR (0.6-point difference, P < .001) and ER (4° difference, P = .010) were significantly greater in healthy contralateral shoulders. The IR strength of the operated shoulder was significantly less than that of the healthy shoulder in concentric and eccentric testing (range of deficit, 4%-6%; P < .05). Also, the ER strength of the operated shoulder was significantly less than that of the healthy shoulder in concentric testing (11% deficit, P < .05). Subscapularis muscle volume was significantly greater in the operated shoulder (4% difference, P = .022), and there was no significant difference in fat fraction (P = .114). Conclusions: The primary open Latarjet procedure was associated with significantly decreased active IR and ER and strength when compared with the healthy contralateral shoulder. The clinical influence of these findings is yet to be defined. There was no increased subscapularis muscle fatty degeneration but a minimal hypertrophy on the operated side at long-term follow-up.