Fatty infiltration of the cervical multifidus musculature and their clinical correlates in spondylotic myelopathy

Correlation between degeneration of cervical intervertebral disc and degeneration of paravertebral muscle

Objective

To investigate the relationship between degeneration of cervical intervertebral disc and degeneration of paravertebral muscles[multifidus (MF), cervical semispinalis (SCer), semispinalis capitis (SCap) and splenius capitis (SPL)].

Methods

82 patients with chronic neck pain were randomly selected, including 43 males and 39 females, with 50.73 0.7.51 years old. All patients were scanned by 3.0T MRI Philips Ingenia performed conventional MRI sequence scanning and fat measurement sequence mDIXON-Quant scanning of cervical. Fat infiltration (FI) and cross-sectional area (CSA) of cervical paravertebral muscle (MF, SCer, SCap and SPL) at central level of C5-6 disc were measured by Philips 3.0T MRI image post-processing workstation. According to Pfirrmann grading system, there was no grade I in the included cases. The number of grade IIr IV cases were n=16, 40, 19 and 7 respectively. CSA and FI of cervical paravertebral muscles were compared with t test or one-way ANOVA, Spearman correlation analysis was used to evaluate the correlation between age, disc degeneration, and CSA, FI of cervical paravertebral muscles, and multiple linear regression analysis was used to analyze the independent influencing factors of CSA and FI.

Results

CSA of cervical paravertebral muscles in male patients was significantly higher than that in female patients (all P<0.001), but there was no significant difference in FI (all P>0.05). Age was weakly correlated with CSA of MF+SCer, moderately correlated with CSA of SCap and SPL (r=-0.256, -0.355 and -0.361, P<0.05), weakly correlated with FI of SCap and SPL (r= 0.182 and 0.264, P<0.001), moderately correlated with FI of MF+SCer (r=0.408, P<0.001). There were significant differences in FI with disc degeneration (P<0.001, P=0.028 and P=0.005). Further correlation analysis showed that disc degeneration was strongly correlated with FI of MF+SCer (r=0.629, P<0.001), and moderately correlated with FI of SCap and SPL (r=0.363, P=0.001; r=0.345, P=0.002). Multiple linear regression analysis showed that sex and age were the influencing factors of CSA of SCap and SPL, sex was the independent influencing factor of CSA of MF+SCer, and disc degeneration was the independent influencing factor of FI.

Conclusions

Age is negatively correlated with CSA and positively correlated with FI. Disc degeneration was correlated with FI of paravertebral muscles, especially with FI of MF and SCer. Sex and age were the influencing factors of CSA, while disc degeneration was the independent influencing factor of FI.

Morphological Changes of Deep Extensor Neck Muscles in Relation to the Maximum Level of Cord Compression and Canal Compromise in Patients With Degenerative Cervical Myelopathy

STUDY DESIGN

Cross-sectional study.

OBJECTIVES

To examine the relationship between morphological changes of the deep extensor neck muscles in patients with degenerative cervical myelopathy (DCM) and the level of maximum spinal cord compression (MSCC) and canal compromise (MCC). A secondary objective was to examine the relationship between muscle morphological changes with neck pain and functional scores related to neck pain and interference.

METHODS

A total of 171 patients with DCM were included. Total cross-sectional area (CSA), functional CSA (fat free area, FCSA), ratio of FCSA/CSA (fatty infiltration) and asymmetry of the multifidus (MF) and semispinalis cervicis (SCer) together, and cervical muscle as a group (eg, MF, SCer, semispinalis capitis, splenius capitis) were obtained from T2-weighted axial MR images at mid-disc, at the level of maximum cord compression and the level below. The relationship between the muscle parameters of interest, MSCC, MCC and functional scores including the Neck Disability Index (NDI) was assessed using multivariate linear regression models, adjusting for age, body mass index and sex.

RESULTS

Greater MF + Scer fatty infiltration was associated with greater MCC (P = .032) and MSCC (P = .049) at the same level. Greater asymmetry in MF + SCer CSA was also associated with greater MCC (P = .006). Similarly, greater asymmetry in FCSA and FCSA/CSA of the entire extensor muscle was associated with greater MCC (P = .011, P = .013). There was a negative association between asymmetry in FCSA MF + SCer, FCSA/CSA MF + SCer and FCSA/CSA group muscles with NDI score at the level below.

CONCLUSION

Greater MCC is associated with increased fatty infiltration and greater asymmetry of the deep cervical muscles in patients with DCM. A negative association between muscle asymmetry and NDI scores was also observed which has implications for clinical prediction around axial neck pain.

Cervical Multifidus and Longus Colli Ultrasound Differences among Patients with Cervical Disc Bulging, Protrusion and Extrusion and Asymptomatic Controls: A Cross-Sectional Study

The aim of this study was to analyze the differences in morphological and histological features of the cervical multifidus (CM) and longus colli (LC) muscles among patients with cervical disc bulging, protrusion, or extrusion. Fifteen patients with cervical disc bulging (20% male, mean age: 48.5, standard deviation (SD) 7.5 years), fifteen with cervical disc protrusion (6% male, mean age: 43, SD 7.8 years), and fifteen with cervical disc extrusion (40% male, mean age: 44, SD 8 years) diagnosed via clinical and imaging findings participated in this study. Additionally, fifteen asymptomatic controls (40% male, mean age: 40.4, SD 9.7 years) were also included. The following ultrasound measurements, cross-sectional area (CSA), anterior-posterior distance (APD), lateral dimension (LD), and mean echo-intensity (EI) of the CM and LC at C5-C6 level were examined by an assessor blinded to the subject's condition. The results revealed no group ×side significant differences among the groups (p > 0. 00625). However, group effects were found for APD and MEI of the CM (p = 0.006 and p < 0.001, respectively) and CSA, APD and MEI of the LC (all, p < 0.001). The LD of the LC muscle and the APD and LD of the CM were negatively associated with related disability (p < 0.01; p < 0.05 and p < 0.01, respectively), and pain intensity was negatively associated with LC APD and LD (both p < 0.05). These results suggest that US can be used to detect bilateral morphological changes in deep cervical flexors and extensors to discriminate patients with cervical disc alterations.

The association between morphological characteristics of paraspinal muscle and spinal disorders

BACKGROUND

Spinal disorders affect millions of people worldwide, and can cause significant disability and pain. The paraspinal muscles, located on either side of the spinal column, play a crucial role in the movement, support, and stabilization of the spine. Many spinal disorders can affect paraspinal muscles, as evidenced by changes in their morphology, including hypertrophy, atrophy, and degeneration.

OBJECTIVES

The objectives of this review were to examine the current literature on the relationship between the paraspinal muscles and spinal disorders, summarize the methods used in previous studies, and identify areas for future research.

METHODS

We reviewed studies on the morphological characteristics of the paravertebral muscle and discussed their relationship with spinal disorders, as well as the current limitations and future research directions.

RESULTS

The paraspinal muscles play a critical role in spinal disorders and are important targets for the treatment and prevention of spinal disorders. Clinicians should consider the role of the paraspinal muscles in the development and progression of spinal disorders and incorporate assessments of the paraspinal muscle function in clinical practice.

CONCLUSION

The findings of this review highlight the need for further research to better understand the relationship between the paraspinal muscles and spinal disorders, and to develop effective interventions to improve spinal health and reduce the burden of spinal disorders.

Cervical muscle morphometry and composition demonstrate prognostic value in degenerative cervical myelopathy outcomes

Objectives

This study aimed to examine whether preoperative cervical muscle size, composition, and asymmetry from magnetic resonance imaging (MRI) can predict post-operative outcomes in patients with degenerative cervical myelopathy (DCM).

Methods

A total of 171 patients with DCM were included. Relative total cross-sectional area (RCSA), functional CSA (fat-free area, FCSA), ratio of FCSA/CSA (fatty infiltration) and asymmetry of the multifidus (MF) and semispinalis cervicis (SCer) together (MF + SCer), and cervical muscle as a group (MF, SCer, semispinalis capitis, and splenius capitis) were obtained from T2-weighted axial MR images at the mid-disk, at the level of maximum cord compression and the level below. Univariate and multivariate linear regression analyses were used to assess the relationship between baseline cervical muscle measurements of interest with the modified Japanese Orthopedic Association (mJOA), Nurick Classification, Neck Disability Index (NDI), and SF-36 health survey at 6-month and 12-month post-surgery.

Results

Lower RCSA of MF + SCer, less CSA MF + SCer asymmetry and greater FCSA/CSA for the cervical muscle group (e.g., less fatty infiltration), and younger age were significant predictors of higher mJOA scores (e.g., less disability) at 6-month and 12-month post-surgery (all p < 0.05). Greater CSA asymmetry in MF + SCer and lower FCSA/CSA (e.g., more fatty infiltration) for the cervical muscle group were significant predictors of higher Nurick scores (e.g., more disability) at 6-month and 12-month post-surgery (all p < 0.05). Lower FCSA MF + Scer asymmetry, lower FCSA/CSA asymmetry of the muscle group, and greater RCSA MF + SCer were significant predictors of higher NDI scores at 6-month and 12-month post-surgery. Finally, greater FCSA/CSA asymmetry of the MF + SCer, greater FCSA asymmetry of the muscle group, greater RCSA of the muscle group, and greater CSA asymmetry of MF + SCer were significant predictors of lower post-operative SF-36 scores at 6- and 12-month post-surgery.

Conclusion

Our result suggested that cervical paraspinal muscle morphology, specifically greater asymmetry, and fatty infiltration may be important predictors of functional recovery and post-surgical outcomes in patients with DCM.

Fatty infiltration of the cervical multifidus musculature and its clinical correlation to cervical spondylosis

PURPOSE

Fat infiltration (FI) of the deep neck extensor muscles has been shown to be associated with poor outcomes in cervical injury, mechanical neck pain, and axial symptoms after cervical spine surgery. However, information is scarce on the severity of FI in cervical extensors associated with different clinical syndromes in patients with cervical spondylosis.

OBJECTIVE

To investigate the relationship between the severity of FI in the cervical multifidus musculature and its clinical correlates in the syndromes and sagittal alignment of patients with cervical spondylosis.

METHODS

This study was conducted as a retrospective study of twenty-eight healthy volunteers (HV) together with sixty-six patients who underwent cervical radiculopathy (CR), degenerative myelopathy (DM), and axial joint pain (AJP) from January 2020 to March 2022. MRI was used to measure the fat cross-sectional area (FCSA), functional muscle cross-sectional area (FMCSA), total muscle cross-sectional area (TMCSA), FI ratio of the cervical multifidus musculature at each cervical level from the C3 to C6 segments and the cervical lordosis angle in the included subjects.

RESULTS

The difference in the FCSA and FI ratio in patient groups with cervical spondylosis was significantly greater than that of the HV group (P < 0.05), and the Cobb angle of the DM group, AJP group and HV group was significantly greater than that of the CR group (P < 0.05). The FI ratio comparison showed no significant difference by sex, and the comparison of FCSA, FMCSA, TMCSA and FI ratio showed no significant difference by age range from 35 to 69 in the included subjects. The FCSA and TMCSA in patients with cervical spondylosis were positively related to the Cobb angle (r_s= 0.336, P = 0.006, r_s =0.319, P = 0.009, respectively), and the FI ratio was inversely correlated with the Cobb angle (r_s= -0.285, P = 0.020) and positively correlated with age (r_s =0.261, P = 0.034). In the HV group, FMCSA was inversely correlated with age (r_s= -0.400, P = 0.035), while the FI ratio had a positive correlation with age (r_s= -0.423, P = 0.025).

CONCLUSION

Compared with healthy subjects, a more severe degree of FI in the multifidus musculature and sagittal imbalance were found in patients with cervical spondylosis. These two imaging features are considered to be important concomitant phenomena of cervical spondylosis, and the more severe FI is, the worse the sagittal imbalance. However, each syndrome had no obvious difference in FI in the multifidus musculature.

Predictive Effect of Cervical Sagittal Parameters and Corresponding Segmental Paravertebral Muscle Degeneration on the Occurrence of Cervical Kyphosis Following Cervical Laminoplasty

BACKGROUND

Cervical sagittal parameters and paravertebral muscle degeneration are important factors for the occurrence of cervical spondylotic myelopathy. However, the relationship between the 2 risk factors and cervical kyphosis following cervical laminoplasty remains unknown.

METHODS

A total of 130 patients undergoing cervical laminoplasty were enrolled from July 2018 to July 2020 and were followed up for at least 24 months. Clinical recovery was recorded, including the Japanese Orthopedic Association, neck disability index and visual analog scale scores. Radiographic sagittal parameters were measured on cervical lateral radiographs: T1 slope (T1S), C2-C7 Cobb lordotic angle (CLA), C2-C7 sagittal vertical axis, O-C2 angle, and T1S-CLA. The magnetic resonance imaging (MRI) parameters of the paraspinal muscles were also measured, including cross-sectional area and fat infiltration (FI). The patients were divided into a kyphosis group and a lordosis group based on the last follow-up results of CLA. Multivariate logistic analysis was performed to analyze risk factors for kyphosis following laminoplasty.

RESULTS

Thirty-two patients were assigned to the kyphosis group and 98 were assigned to the lordosis group. Patient baseline and surgical information in the 2 groups showed no statistically significant difference. In the comparison of clinical recovery, patients with kyphosis showed a lower Japanese Orthopedic Association recovery rate than the lordosis group. For the radiographic parameters and muscle condition comparison, CLA, T1S-CLA, and FI were the most significant parameters. The logistic regression revealed that T1S-CLA and FI were the most important variables that predicted kyphosis.

CONCLUSIONS

We concluded that FI remarkably differed in the paraspinal muscles in the 2 groups. Multivariate logistic regression demonstrated that T1S-CLA and FI significantly influenced the process of kyphosis after cervical laminoplasty.

Inter-Examiner Disagreement for Assessing Cervical Multifidus Ultrasound Metrics Is Associated with Body Composition Features

Ultrasound imaging (US) is a biosensing technique that is widely used in several healthcare disciplines (including physiotherapy) for assessing multiple muscle metrics, such as muscle morphology and quality. Since all biosensors need to be tested in order to demonstrate their reliability, accuracy, sensitivity, and specificity, identifying factors that affect their diagnostic accuracy is essential. Since previous studies analyzed the impact of sociodemographic but not body composition characteristics in US errors, this study aimed to assess whether body composition metrics are associated with ultrasound measurement errors. B-mode images of the lumbar multifidus muscle at the L5 level were acquired and analyzed in 47 healthy volunteers by two examiners (one experienced and one novice). The cross-sectional area, muscle perimeter, and mean echo intensity were calculated bilaterally. A correlation analysis and a multivariate linear regression model were used for assessing the inter-examiner differences with respect to body composition metrics. The results demonstrated good-to-excellent reliability estimates for the cross-sectional area, muscle perimeter, aspect ratio, roundness, circularity, and mean brightness metrics (all ICC > 0.85). However, solidity showed unacceptable reliability (ICC < 0.7). Age, height, total lean mass, trunk lean mass, and water volume were associated with inter-examiner disagreement on mean echo intensity. Cross-sectional area, perimeter, and roundness measurement errors were associated with lean mass and water volume.

Association Between the Cervical Extensor Musculature and the Demographic Features, Symptoms, and Sagittal Balance in Patients with Multilevel Cervical Spondylotic Myelopathy

OBJECTIVE

To obtain the quantitative measurements of the muscle morphology of cervical extensors in patients with multilevel cervical spondylotic myelopathy, and determine whether the morphological parameter of each muscle correlates with the patients' demographic features, symptoms, and cervical sagittal balance.

METHODS

We retrospectively evaluated 100 hospitalized patients scheduled to undergo surgery for multilevel cervical spondylotic myelopathy. Demographic data, including age, sex, and body mass index, were recorded, and symptoms were evaluated using the visual analog scale (VAS), neck disability index (NDI), and modified Japanese Orthopedic Association scale scores. The cross-sectional area (CSA) of the multifidus, semispinalis capitis, semispinalis cervicis, splenius capitis and splenius cervicis were measured on magnetic resonance imaging. The CSA of the total extensor muscles, deep extensor muscles (DEM, consisting of multifidus and semispinalis capitis), and superficial extensor muscles (consisting of semispinalis cervicis, splenius capitis and splenius cervicis) were calculated. The adjusted CSA (aCSA) was calculated as the CSA of the muscle/CSA of the corresponding vertebral body. The fat infiltration ratio (FIR) of the posterior extensor muscles was assessed using a pseudocoloring technique. Sagittal parameters, including cervical lordosis (CL), C2-7 cervical sagittal vertical axis (SVA), T1-slope, mismatch between T1-slope and CL (T1S-CL), and range of motion, were measured. The measured parameters were compared between the males and the females, between the patients with higher muscle aCSA and the patients with lower muscle aCSA, and between the patients with and without sagittal balance. A Pearson correlation analysis was conducted to determine the correlations between the paraspinal muscle measurements, and the clinical and radiographic parameters.

RESULTS

There were 67 males and 33 females in this study, and the mean age was 59.22 ± 9.54 years. Compared with females, male patients showed higher CSA and aCSA of extensor muscles. Patients with lower muscle aCSA were significantly older and had worse NDI scores, with significantly greater C2-7 SVA and T1S-CL. Patients with sagittal imbalance showed significantly lower aCSA of total extensor muscles and DEM, as well as a significantly higher FIR. Age was significantly correlated with the aCSA of each measured muscle and the FIR. The aCSA of the DEM was correlated with the NDI score, the visual analog scale score, the SVA, the T1-slope, and the T1S-CL.

CONCLUSIONS

In patients with multilevel CSM, age and sex were demographic factors that were highly correlated with muscle morphology changes. Extensor muscles, especially DEM, play important roles in maintaining cervical sagittal balance and are associated with the severity of neck symptoms.

The fatty infiltration into cervical paraspinal muscle as a predictor of postoperative outcomes: A controlled study based on hybrid surgery

BACKGROUND

The cervical paraspinal muscle (CPM) has an essential role in positioning, stabilizing and directing the cervical spine. However, information is lacking regarding the influence of CPM on outcomes following anterior cervical surgery. This study aims to evaluate the association of fatty infiltration (FI) of CPM with postoperative outcomes in patients undergoing hybrid surgery (HS) and analyze the relationship between FI and cross-sectional area (CSA) of CPM.

METHODS

A retrospective analysis was performed on 110 consecutive patients undergoing continuous 2-level HS. According to Goutallier classification of multifidus FI, the patients were divided into normal, moderate, and severe groups. Image J software was employed to outline and analyze CPM. Clinical outcomes and radiographic parameters were collected and evaluated for relevant comparisons.

RESULTS

Visible FI was identified in 69.1% of patients (76/110), with a propensity in elderly patients (p = 0.053). No statistically significant differences were presented among the three groups regarding pre- and postoperative clinical evaluation scores. The cervical lordosis was significantly higher in the normal group before surgery (p = 0.029). Likewise, the sagittal vertical axis (SVA) was significantly higher in the severe group than the normal group at the final follow-up (p = 0.046). The function spine unit angle and disc angle of arthroplasty levels were significantly lower in the severe group than the normal group at follow-ups. Moreover, after correction according to vertebral body area, no statistically significant relationship existed between CSA ratio and FI grade.

CONCLUSION

CPM degeneration is common and age-related in patients with cervical disc degenerative disease. More importantly, there was a significant positive correlation between severe FI of CPM and postoperative sagittal balance disorder, particularly in C2-7 SVA and segmental alignment of arthroplasty level. Meanwhile, FI of CPM appears to have no impact on clinical outcomes and reveals small correlations to CSA.

Association Between Deep Posterior Cervical Paraspinal Muscle Morphology and Clinical Features in Patients With Cervical Ossification of the Posterior Longitudinal Ligament

STUDY DESIGN

A retrospective observational study.

OBJECTIVE

To clarify the association of the paraspinal muscle area and composition with clinical features in patients with cervical ossification of the posterior longitudinal ligament (OPLL).

METHODS

Consecutive patients with cervical OPLL who underwent cervical magnetic resonance imaging (MRI) before surgery were reviewed. The cross-sectional area (CSA) and fatty infiltration ratio (FI%) of deep posterior cervical paraspinal muscles (multifidus [MF] and semispinalis cervicis [SCer]) were examined. We assessed the association of paraspinal muscle measurements with the clinical characteristics and clinical outcomes, such as Neck Disability Index (NDI) score. Moreover, we divided the patients into 2 groups according to the extent of the ossified lesion (segmental and localized [OPLL-SL] and continuous and mixed [OPLL-CM] groups) and compared these variables between the 2 groups.

RESULTS

49 patients with cervical OPLL were enrolled in this study. The FI% of the paraspinal muscles was significantly associated with the number of vertebrae (ρ = 0.283, p = 0.049) or maximum occupancy ratio of OPLL (ρ = 0.397, p = 0.005). The comparative study results indicated that the NDI score was significantly worse (OPLL-SL, 22.9 ± 13.7 vs. OPLL-CM, 34.4 ± 13.7) and FI% of SCer higher (OPLL-SL, 9.1 ± 1.7% vs. OPLL-CM, 11.1 ± 3.7%) in the OPLL-CM group than those in the OPLL-SL group.

CONCLUSIONS

Our results suggest that OPLL severity may be associated with fatty infiltration of deep posterior cervical paraspinal muscles, which could affect neck disability in patients with cervical OPLL.

Greater muscle volume and muscle fat infiltrate in the deep cervical spine extensor muscles (multifidus with semispinalis cervicis) in individuals with chronic idiopathic neck pain compared to age and sex-matched asymptomatic controls: a cross-sectional study

Muscle size and composition (muscle volume and muscle fat infiltrate [MFI]) may provide insight into possible mechanisms underpinning chronic idiopathic neck pain, a common condition with no definitive underlying pathology. In individuals with chronic idiopathic neck pain > 3 months and age- and sex-matched asymptomatic controls, muscle volumes of levator scapulae, multifidus including semispinalis cervicis (MFSS), semispinalis capitis, splenius capitis including splenius cervicis (SCSC), sternocleidomastoid and longus colli from C3 through T1 were quantified from magnetic resonance imaging. Between-group differences were determined using linear mixed models, accounting for side (left or right), muscle, spinal level, sex, age, and body mass index (BMI). Individuals with pain had greater muscle volume (mean difference 76.8mm³; 95% CI 26.6-127.0; p = .003) and MFI (2.3%; 0.2-4.5; p = .034) of the MFSS compared to matched controls with no differences in relative volume, accounting for factors associated with the outcomes: muscle, spinal level, side (left had smaller volume, relative volume and MFI than right), sex (females had less volume and relative volume than males), age (older age associated with less relative volume and greater MFI), and BMI (higher BMI associated with greater muscle volume and MFI). Greater MFI in individuals with chronic idiopathic neck pain suggests a possible underlying mechanism contributing to neck pain. Perspective: These findings suggest MFI in the MFSS may be radiologic sign, potentially identifying patients with a less favourable prognosis. Future studies are needed to confirm this finding and determine if MFI is a contributor to the development or persistence of neck pain, or consequence of neck pain.

Identifying Demographic, Clinical, Muscular and Histological Factors Associated with Ultrasound Cervical Multifidus Measurement Errors in a Chronic Neck Pain Population

Ultrasound imaging (US) is a widely used imaging tool in physiotherapy for assessing muscle morphology and quality, among other purposes, such as ensuring the patients’ safety during invasive procedures or providing visual feedback during motor control exercises. Identifying factors associated with measurement errors is essential to target avoid bias in high-risk of bias populations. Therefore, this study aimed to assess whether demographic, clinical, muscular and histological factors are associated with ultrasound measurement errors in patients with idiopathic chronic neck pain. B-mode images were acquired and analyzed in 126 patients with chronic neck pain by two experienced examiners. Cross-sectional area, muscle perimeter, mean echo intensity and percentage of fatty infiltration were analyzed. The interexaminer agreement was assessed by calculating the absolute error, intraclass correlation coefficient (ICC), standard error of measurement (SEM) and minimal detectable changes (MDC). A Pearson’s correlation matrix including all variables was calculated to conduct a multivariate linear stepwise regression model for estimating the explained variance for each measurement error. Results demonstrated excellent reliability (ICC = 0.965) for assessing the cross-sectional area, and good reliability for assessing the muscle perimeter, mean echo intensity and intramuscular infiltrates estimation (ICC = 0.898, 0.882 and 0.758, respectively). Although clinical variables were not associated with measurement errors (p > 0.05), multiple correlations were found between demographic and cervical multifidus characteristics with measurement errors.

Multifidus Sarcopenia Is Associated With Worse Patient-reported Outcomes Following Posterior Cervical Decompression and Fusion

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The present study is the first to assess the impact of paraspinal sarcopenia on patient-reported outcome measures (PROMs) following posterior cervical decompression and fusion (PCDF).

SUMMARY OF BACKGROUND DATA

While the impact of sarcopenia on PROMs following lumbar spine surgery is well-established, the impact of sarcopenia on PROMs following PCDF has not been investigated.

MATERIALS AND METHODS

We performed a retrospective review of patients undergoing PCDF from C2 to T2 at a single institution between the years 2017 and 2020. Two independent reviewers who were blinded to the clinical outcome scores utilized axial cuts of T2-weighted magnetic resonance imaging sequences to assess fatty infiltration of the bilateral multifidus muscles at the C5-C6 level and classify patients according to the Fuchs Modification of the Goutalier grading system. PROMs were then compared between subgroups.

RESULTS

We identified 99 patients for inclusion in this study, including 28 patients with mild sarcopenia, 45 patients with moderate sarcopenia, and 26 patients with severe sarcopenia. There was no difference in any preoperative PROM between the subgroups. Mean postoperative Neck Disability Index scores were lower in the mild and moderate sarcopenia subgroups (12.8 and 13.4, respectively) than in the severe sarcopenia subgroup (21.0, P <0.001). A higher percentage of patients with severe multifidus sarcopenia reported postoperative worsening of their Neck Disability Index (10 patients, 38.5%; P =0.003), Visual Analog Scale Neck scores (7 patients, 26.9%; P =0.02), Patient-Reported Outcome Measurement Information System Physical Component Scores (10 patients, 38.5%; P =0.02), and Patient-Reported Outcome Measurement Information System Mental Component Scores (14 patients, 53.8%; P =0.02).

CONCLUSION

Patients with more severe paraspinal sarcopenia demonstrate less improvement in neck disability and physical function postoperatively and are substantially more likely to report worsening PROMs postoperatively.

LEVEL OF EVIDENCE

3.

Fat Infiltration of Multifidus Muscle Is Correlated with Neck Disability in Patients with Non-Specific Chronic Neck Pain

Background: Chronic non-specific neck pain (CINP) is common, but the etiology remains unclear. This study aimed to examine the relationship between cervical muscle composition (cervical multifidus and longus capitis/longus colli), morphometry, range of movement, muscle function, and disability severity (Neck Disability Index) in patients with CINP. Methods: From September 2020 to July 2021, subjects underwent cervical MRI and clinical tests (cervical range of motion, cranio-cervical flexion test, neck flexor, and extensor muscle endurance). MRI analysis comprised muscle cross-sectional area, volume, and fat infiltration of multifidus and longus colli between C4 and C7 levels. Results: Twenty-five participants were included. Multiple linear regression analysis indicated that NDI was positively correlated with the volume percentage of fat infiltration of the multifidus (B = 0.496), negatively correlated with fat-free muscle volume of the multifidus normalized by subject height (B = −0.230), and accounted for 32% of the variance. There was no relationship between neck disability and longus capitis/longus colli morphology. We also found no relationship between neck disability scores, neck flexor or extensor muscle endurance, or the outcome motor control test of craniocervical flexion (p > 0.05). Conclusions: Neck disability was moderately correlated with the percentage of fat volume in the multifidus muscle and fat-free volume of the multifidus. There was no relationship between NDI scores and muscle function test outcomes or any fat or volume measures pertaining to the longus colli muscle.

Association between muscle morphology changes, cervical spine degeneration and clinical features in patients with chronic nonspecific neck pain: a magnetic resonance imaging analysis

PURPOSE

The primary objective of the present study was to investigate the correlations among cervical paraspinal muscle morphology changes (fatty infiltration (FI) and muscle atrophy), cervical degeneration and clinical features in patients with chronic nonspecific neck pain (CNSNP).

METHODS

The magnetic resonance imaging (MRI) data of 55 consecutive patients (average age 35.80) with CNSNP were analyzed in this cross-sectional study. Muscle morphology changes in seven groups of paraspinal muscles, indicated by the adjusted cross-sectional area (aCSA) and FI ratio (FI%), were measured from C3/4 to C6/7. The correlations of these changes with disc degeneration, cervical balance (C2-7 angle and cervical alignment) and clinical features (severity of neck pain and related disability and the frequency of acute neck pain (ANP) recurrence) were evaluated.

RESULTS

Significant correlations between FI% and aCSA and the grade of disc degeneration were observed in specific muscle groups at each level (p<0.05). Morphological changes in the deep extensors and superficial paraspinal muscles were significantly associated with cervical balance parameters (p<0.05). The FI% showed a significant positive correlation, while aCSA showed a significant negative correlation with the severity of neck pain and related disability (p<0.05). Correlations between morphological changes and the frequency of ANP recurrence were also present for some muscles (p<0.05).

CONCLUSION

Correlations among muscle morphology changes, cervical degeneration and clinical features were established for patients with CNSNP, and muscle volume changes and FI might affect CNSNP in diverse manners through different paraspinal muscle groups. These results implicated the complex contribution of muscle morphological changes to cervical degeneration and the clinical course of CNSNP.

Cervical disc degeneration: important considerations for the manual therapist

Cervical disc degeneration (CDD) is a progressive, age-related occurrence that is frequently associated with neck pain and radiculopathy. Consistent with the majority of published clinical practice guidelines (CPG) for neck pain, the 2017 American Physical Therapy Association Neck Pain CPG recommends cervical manipulation as an intervention to address acute, subacute, and chronic symptoms in the 'Neck Pain With Mobility Deficits' category as well for individuals with 'Chronic Neck Pain With Radiating Pain'. While CPGs are evidence-informed statements intended to help optimize care while considering the relative risks and benefits, these guidelines generally do not discuss the mechanical consequences of underlying cervical pathology nor do they recommend specific manipulation techniques, with selection left to the practitioner's discretion. From a biomechanical perspective, disc degeneration represents the loss of structural integrity/failure of the intervertebral disc. The sequelae of CDD include posterior neck pain, segmental hypermobility/instability, radicular symptoms, myelopathic disturbance, and potential vascular compromise. In this narrative review, we consider the mechanical, neurological, and vascular consequences of CDD, including information on the anatomy of the cervical disc and the mechanics of discogenic instability, the anatomic and mechanical basis of radiculitis, radiculopathy, changes to the intervertebral foramen, the importance of Modic changes, and the effect of spondylotic hypertrophy on the central spinal canal, spinal cord, and vertebral artery. The pathoanatomical and biomechanical consequences of CDD are discussed, along with suggestions which may enhance patient safety.

Multi-muscle deep learning segmentation to automate the quantification of muscle fat infiltration in cervical spine conditions

Muscle fat infiltration (MFI) has been widely reported across cervical spine disorders. The quantification of MFI requires time-consuming and rater-dependent manual segmentation techniques. A convolutional neural network (CNN) model was trained to segment seven cervical spine muscle groups (left and right muscles segmented separately, 14 muscles total) from Dixon MRI scans (n = 17, 17 scans < 2 weeks post motor vehicle collision (MVC), and 17 scans 12 months post MVC). The CNN MFI measures demonstrated high test reliability and accuracy in an independent testing dataset (n = 18, 9 scans < 2 weeks post MVC, and 9 scans 12 months post MVC). Using the CNN in 84 participants with scans < 2 weeks post MVC (61 females, 23 males, age = 34.2 ± 10.7 years) differences in MFI between the muscle groups and relationships between MFI and sex, age, and body mass index (BMI) were explored. Averaging across all muscles, females had significantly higher MFI than males (p = 0.026). The deep cervical muscles demonstrated significantly greater MFI than the more superficial muscles (p < 0.001), and only MFI within the deep cervical muscles was moderately correlated to age (r > 0.300, p ≤ 0.001). CNN's allow for the accurate and rapid, quantitative assessment of the composition of the architecturally complex muscles traversing the cervical spine. Acknowledging the wider reports of MFI in cervical spine disorders and the time required to manually segment the individual muscles, this CNN may have diagnostic, prognostic, and predictive value in disorders of the cervical spine.

The Role of Cervical Muscles Morphology in the Surgical Treatment of Degenerative Disc Disease: Clinical Correlations Based on Magnetic Resonance Imaging Studies

Cervical spine musculature still remains a less studied component of the cervical spine anatomical compartments, although it plays a significant role in the mobility of the head and the preservation of cervical spine alignment. The goal of this study was to extract any significant information from the literature regarding the role of cervical spine muscles morphology in the outcome of surgically treated patients for degenerative disc disease (DDD) based on preoperative magnetic resonance imaging (MRI) studies. Eleven clinical case series were found, from which four were prospective and seven were retrospective. Six studies were concentrated on anterior approaches and five studies on posterior approaches in the cervical spine. In posterior approaches aiming at the preservation of muscles attachments and overall less surgical manipulations, results on cervical lordosis, axial pain and patient’s functionality were found superior to traditional laminectomies. The study of cross-sectional areas (CSAs) of deep paraspinal muscles in the cervical spine could add significant information for the spine surgeon such as the prediction of adjacent level disease (ALD), fusion failure, axial pain persistence, postoperative cervical alignment and patient’s postoperative functionality. It seems that MRI studies focusing on muscle layers of the cervical spine could add significant information for the spinal surgeon regarding the final surgical outcome in terms of pain and function expression. Larger multicenter clinical studies are a necessity in defining the role of the muscle component of the cervical spine in the surgical treatment of DDD.

Fatty infiltration in cervical flexors and extensors in patients with degenerative cervical myelopathy using a multi-muscle segmentation model

Background

In patients with degenerative cervical myelopathy (DCM) that have spinal cord compression and sensorimotor deficits, surgical decompression is often performed. However, there is heterogeneity in clinical presentation and post-surgical functional recovery.

Objectives

Primary: a) to assess differences in muscle fat infiltration (MFI) in patients with DCM versus controls, b) to assess association between MFI and clinical disability. Secondary: to assess association between MFI pre-surgery and post-surgical functional recovery.

Study design

Cross-sectional case control study.

Methods

Eighteen patients with DCM (58.6 ± 14.2 years, 10 M/8F) and 25 controls (52.6 ± 11.8 years, 13M/12 F) underwent 3D Dixon fat-water imaging. A convolutional neural network (CNN) was used to segment cervical muscles (MFSS- multifidus and semispinalis cervicis, LC- longus capitis/colli) and quantify MFI. Modified Japanese Orthopedic Association (mJOA) and Nurick were collected.

Results

Patients with DCM had significantly higher MFI in MFSS (20.63 ± 5.43 vs 17.04 ± 5.24, p = 0.043) and LC (18.74 ± 6.7 vs 13.66 ± 4.91, p = 0.021) than controls. Patients with increased MFI in LC and MFSS had higher disability (LC: Nurick (Spearman’s ρ = 0.436, p = 0.003) and mJOA (ρ = -0.399, p = 0.008)). Increased MFI in LC pre-surgery was associated with post-surgical improvement in Nurick (ρ = -0.664, p = 0.026) and mJOA (ρ = -0.603, p = 0.049).

Conclusion

In DCM, increased muscle adiposity is significantly associated with sensorimotor deficits, clinical disability, and functional recovery after surgery. Accurate and time efficient evaluation of fat infiltration in cervical muscles may be conducted through implementation of CNN models.

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.

Age- and gender-related variations of cervical muscle composition using chemical shift encoding-based water-fat MRI

PURPOSE

To understand fat distribution patterns and ectopic fat deposition in healthy adults and to provide normative data, encompassing the borders of physiological regional muscle composition. For this purpose chemical shift encoding-based water-fat Magnetic Resonance Imaging (MRI) was used for proton density fat fraction (PDFF) calculations.

MATERIAL AND METHODS

91 volunteers were enrolled (male: n = 28, age = 36.6 ± 11.4 years; female: n = 63, age = 38.5 ± 15.1 years). PDFF values combined for the multifidus, semispinalis and spinalis cervicis muscles at the level of the 3rd cervical vertebral body (C3), the 5th cervical vertebral body (C5) and the first thoracic vertebral body (Th1) were extracted.

RESULTS

The paraspinal musculature at C3 (14.8 ± 10.1 % vs. 19.2 ± 11.0 %; p = 0.029) and Th1 (13.8 ± 7.0 % vs 17.7 ± 7.4 %; p = 0.011) showed significantly lower PDFF values in men compared to women. Partial correlation testing with BMI as control variable revealed highly significant correlations between the paraspinal musculature PDFF at C3 (men: r = 0.504, p = 0.007; women: r = 0.279, p = 0.028), C5 (men: r = 0.450, p = 0.019; women: r = 0.347, p = 0.006) and Th1 (men: r = 0.652, p < 0.0001; women: r = 0.443, p < 0.0001) with age in both genders.

CONCLUSION

The present data suggest gender and age-specific fat deposition patterns of the cervical and the upper cervicothoracic paraspinal muscles and may provide reference values for pathology detection.

Deep Learning Convolutional Neural Networks for the Automatic Quantification of Muscle Fat Infiltration Following Whiplash Injury

Muscle fat infiltration (MFI) of the deep cervical spine extensors has been observed in cervical spine conditions using time-consuming and rater-dependent manual techniques. Deep learning convolutional neural network (CNN) models have demonstrated state-of-the-art performance in segmentation tasks. Here, we train and test a CNN for muscle segmentation and automatic MFI calculation using high-resolution fat-water images from 39 participants (26 female, average = 31.7 ± 9.3 years) 3 months post whiplash injury. First, we demonstrate high test reliability and accuracy of the CNN compared to manual segmentation. Then we explore the relationships between CNN muscle volume, CNN MFI, and clinical measures of pain and neck-related disability. Across all participants, we demonstrate that CNN muscle volume was negatively correlated to pain (R = -0.415, p = 0.006) and disability (R = -0.286, p = 0.045), while CNN MFI tended to be positively correlated to disability (R = 0.214, p = 0.105). Additionally, CNN MFI was higher in participants with persisting pain and disability (p = 0.049). Overall, CNN's may improve the efficiency and objectivity of muscle measures allowing for the quantitative monitoring of muscle properties in disorders of and beyond the cervical spine.

Machine Learning for the Prediction of Cervical Spondylotic Myelopathy: A Post Hoc Pilot Study of 28 Participants

BACKGROUND

Cervical spondylotic myelopathy (CSM) severity and presence of symptoms are often difficult to predict based simply on clinical imaging alone. Similarly, improved machine learning techniques provide new tools with immense clinical potential.

METHODS

A total of 14 patients with CSM and 14 controls underwent imaging of the cervical spine. Two different artificial neural network models were trained; 1) to predict CSM diagnosis; and 2) to predict CSM severity. Model 1 consisted of 6 inputs including 3 common imaging scales for the evaluation of cord compression, alongside 3 objective magnetic resonance imaging measurements. The outcome for model 1 was binary to predict CSM diagnosis. Model 2 consisted of 23 input variables derived from probabilistic volume mapping measurements of white matter tracts in the region of compression. The outcome of model 2 was linear, to predict the modified Japanese Orthopedic Association (mJOA) score.

RESULTS

Model 1 was used in predicting CSM. The mean cross-validated accuracy of the trained model was 86.50% (95% confidence interval, 85.16%-87.83%) with a median accuracy of 90.00%. Area under the curve (AUC) was calculated for each repetition. Average AUC for each repetition was 0.947 with a median AUC of 1.0. Average sensitivity, specificity, positive predictive value, and negative predictive value were 90.25%, 85.05%, 81.58%, and 91.94%, respectively. Model 2 was used in modeling mJOA. The mJOA model predicted scores, with a mean and median error of -0.29 mJOA points and -0.08 mJOA points, respectively, mean error per batch was 0.714 mJOA points.

CONCLUSIONS

Machine learning provides a promising method for prediction, diagnosis, and even prognosis in patients with CSM.