Relationships between Paraspinal Muscle and Spinopelvic Sagittal Balance in Patients with Lumbar Spinal Stenosis

A Comprehensive Analysis Between Disk Geometry and Posterior Muscle Characteristics Among Degenerative Spine Patients: An Internal Retrospective Review

STUDY DESIGN

A retrospective Cohort Study.

OBJECTIVE

The aim of this study is to investigate the associations between posterior muscle health characteristics and disk geometry parameters between L1 and S1.

SUMMARY OF BACKGROUND DATA

Paralumbar muscle changes have been associated with clinical outcomes. However, the relationship between disk geometry and paralumbar muscle changes has not been defined.

METHODS

Axial T2 MRI was analyzed for paralumbar muscle measurements, and lateral radiographs were analyzed for disk geometry parameters in patients with disk degeneration. Associations between disk shape and muscle health at each individual lumbar level were evaluated using a partial correlation controlling for age and sex. Demographic data were compared between the listhesis groups, and an ANCOVA analysis controlling for significant demographic parameters was conducted to evaluate differences in muscle characteristics.

RESULTS

In all, 435 patients were included (age: 55.6±15, BMI: 29.5±6, 60.9% female, 41.3% White). Muscle health median characteristics were CSA/BMI=140, LIV=13, and Goutallier Classification of 1. Partial correlations between focal disk parameters and muscle health controlling for age and sex showed moderate significant positive associations between focal lordosis and lumbar indentation value (LIV) at every level L1-S1 (mean r=0.264 between L1 and L5, P<0.001), weak positive association between focal lordosis and CSA/BMI (mean r=0.113 at L2-L5, P <0.03), and weak negative associations between disk height and Goutallier Classification (mean r=0.158 at L1-L5, P<0.03). Listhesis at L4-S1 was stratified, and ANCOVA controlling for sex and age demonstrated no significant association between S and R groups and CSA/BMI, LIV, or Goutallier classification (P>0.1).

CONCLUSIONS

Posterior muscle health was significantly associated with disk shape, especially disk height and disk lordosis, with larger and more lordotic disks being associated with better muscle health. Disk listhesis was not significantly associated with muscle quality when controlling for demographic characteristics, and no differences in muscle health parameters were observed in patients with spondylolisthesis versus retrolisthesis. Overall, the results highlight important associations between lumbar compensation, disk geometry, and posterior muscle health.

The predictive value of multifidus degeneration in osteoporotic vertebral compression fracture patients with kyphosis deformity

BACKGROUND CONTEXT

Osteoporotic vertebral compression fracture (OVCF) causes pain, kyphosis and neurological damage, which significantly affect patients' quality of life. Patients with OVCF are often elderly and have severe osteoporosis, which makes preoperative symptom more serious, postoperative recovery worse and the incidence of postoperative complications high. The paraspinal muscles have been well studied in adult spinal deformities, but there is no conclusive evidence that their findings can be applied to OVCF. The purpose of this study was to evaluate the associations between multifidus (MF) parameters including fat infiltration (FI), relative functional sectional area (rFCSA), relative gross cross-sectional area (rGCSA) and the sagittal parameters, symptom score, and postoperative complications.

PURPOSE

To figure out the potential associations between multifidus muscle (MF) degeneration and patients' quality of life (QoL), sagittal parameters and mechanical complications in osteoporotic vertebral compression fracture (OVCF) patients with kyphosis deformity.

STUDY DESIGN

Retrospective cohort study PATIENT SAMPLE: OVCF patients with kyphosis deformity who underwent corrective surgery between 2008 to 2021.

OUTCOME MEASUREMENTS

MF fat infiltration (MFFI), relative functional cross-sectional area (MFrFCSA), MF relative gross cross-sectional area (MFrGCSA), VAS, ODI, JOA, SRS-22, preoperative, postoperative and last-follow up spine sagittal parameters, postoperative mechanical complications.

METHODS

The study included 108 OVCF patients with kyphosis deformity who underwent corrective surgery and were followed for 2 years. MRI were performed preoperatively to evaluate the paraspinal muscle morphology, including MF fat infiltration (MFFI), relative functional cross-sectional area (MFrFCSA), and MF relative gross cross-sectional area (MFrGCSA). VAS, ODI, JOA, and SRS-22 were conducted preoperatively. Preoperative, postoperative and last-follow up spine sagittal parameters were recorded, as well as sagittal balance, loss of correction results and improvement and deterioration of sagittal parameters. The occurrence of postoperative mechanical complications, including adjacent segment disease, screw loosening, proximal junctional kyphosis, and distal junctional problem were recorded. We analyzed the relationship between MF degeneration and the above parameters.

RESULTS

Strong correlation was observed in VAS and MFFI (rr=0.597, p=.000),MF rFCSA (rr=-0.520, p=.001) and MF rGCSA (rr=-0.461, p=.005), as well as ODI and MF rFCSA (rr=-0.336, p=.042). Preoperatively, strong correlations were observed between MF rFCSA and LL (rr=-0.320, p=.010), TLK (rr=-0.271, p=.026), TK (rr=-0.251,p=.048). MF rGCSA and LL (rr=-0.259, p=.039), TLK (rr=-0.247, p=.043), TK (rr=-0.273, p=.030), GK (rr=-0.381, p=.002) were also strongly correlated. Our study showed strong correlations between MF FI and TLK loss (rr=0.406, p=.003), TK loss (rr=0.332, p=.045);MF rGCSA and SVA loss (rr =-0.367, p=.050), TPA loss (rr =-0.404, p=.030); MF rGCSA and TPA loss (rr =-0.401, p=.031), MF FI and GK loss(rr =0.397, p=.027). MF FI was significantly higher in the complication-presence group(p=.045).

CONCLUSIONS

Multifidus degeneration is significantly associated with QoL, sagittal parameters and mechanical complications in OVCF patients with kyphosis deformity. The pathological changes of paravertebral muscles should be included in the surgical strategy and postoperative paravertebral muscle rehabilitation should be adopted to improve the clinical outcomes of OVCF patients.

Sagittal balance parameters in achondroplasia

Introduction

Lumbar spinal stenosis (LSS) is the main problem for adult achondroplasia (Ach). Sagittal imbalance of the spine may play a role in LSS causing neurogenic claudication in Ach patients.

Research question

The purpose of this study is to describe the sagittal balance parameters in Ach patients.

Methods

A single-centre retrospective study of Ach patients that visited the Neurosurgery outpatient clinic of the Leiden University Medical Centre (LUMC) between 2019 and 2022 was performed. We defined sagittal imbalance by a C7 sagittal vertical axis (SVA) of more than 10 mm.

Results

There were 13 patients with a spinal sagittal imbalance and 15 patients with a balanced spine. In both groups, the sacral slope (SS) was comparable (45.0° and 49.0°, p = 0.305), but exceeding the mean SS in non achondroplasts (38.0°). Lumbar lordosis (LL) was more pronounced in the balanced group (55.5° versus 41.7°, p = 0.019), and positively correlated to SS in contrast to the absence of a correlation in the imbalanced group. Thoracolumbar kyphosis (TLK) was increased comparably in both groups (19.6° and 24.6°), and far exceeding the TLK in non achondroplasts (circa 0°), and in both groups negatively correlated with the LL, although not enough to compensate for the smaller LL in the imbalanced group.

Conclusion

Only if the LL compensates for both a larger SS and TLK, the Ach spine can maintain sagittal balance. An explanation for the current data can be the failure of the lumbar spine to give sufficient lordosis due to degenerative processes.

Correlation between strength/endurance of paraspinal muscles and sagittal parameters in patients with degenerative spinal deformity

BACKGROUND

Sagittal imbalance is a common cause of low back pain and dysfunction in patients with degenerative spinal deformity (DSD), which greatly affects their quality of life. Strength and endurance are important functional physical indexes for assessing muscle condition. However, the correlation between sagittal parameters and paraspinal muscle strength/endurance is not yet clear. The purpose of this study was to analyze the correlation between strength/endurance of paraspinal muscles and sagittal parameters in patients with DSD.

METHODS

There were 105 patients with DSD and 52 healthy volunteers (control group) enrolled. They were divided into the balance group [sagittal vertical axis (SVA) < 5 cm, n = 68] and imbalance group (SVA ≥ 5 cm, n = 37). The maximal voluntary exertion (MVE)/Endurance time (ET) of paravertebral muscles were assessed using the prone position test stand, and the sagittal parameters of the subjects were measured, namely, SVA, thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). Pearson coefficients were used to assess the correlation between paraspinal muscle MVE/ET and sagittal parameters.

RESULTS

MVE and ET of paravertebral muscles in the control group were significantly higher than those in the balance and imbalance groups (P < 0.05), whereas MVE in the balance group was significantly higher than that in the imbalance group (P < 0.05). SVA in the imbalance group was significantly higher than those in the control and balance groups (P < 0.05). SS and TK in the control group were significantly higher than those in the imbalance group (P < 0.05), and PT and PI in the control group were significantly lower than those in the balance and imbalance groups (P < 0.05). LL in the imbalance group was significantly lower than that in the balance and control groups (P < 0.05). MVE, MVE/BH, and MVE/BW of paraspinal muscles in the imbalance group were negatively correlated with SVA and PT. Moreover, they were positively correlated with LL.

CONCLUSIONS

Deformity may cause the decrease of MVE and ET of paraspinal muscles in the prone position in patients with DSD. Furthermore, the decline in MVE of paraspinal muscles may be a predisposing factor for the imbalance observed. The decrease of MVE/BW of paraspinal muscles may be involved in spinal compensation, and it is a sensitive indicator for sagittal imbalance and lumbar lordosis.

MRI grading of spinal stenosis is not associated with the severity of low back pain in patients with lumbar spinal stenosis

Background

Although lumbar spinal stenosis (LSS) often coexists with other degenerative conditions, few studies have fully assessed possible contributing factors for low back pain (LBP) in patients with LSS. The purpose of this study was to identify factors associated with the severity of LBP in patients with LSS.

Methods

The patients with neurogenic claudication caused by LSS, which was confirmed by magnetic resonance imaging (MRI) were included in this cross-sectional study. Data included ratings of LBP, buttock and leg pain, and numbness on a numerical rating scale (NRS), 36-item Short-Form Survey (SF-36) scores, muscle mass measured by bioelectrical impedance analysis, and radiographic measurements including lumbopelvic alignment and slippage. The severity of LSS, endplate defects, Modic endplate changes, intervertebral disc degeneration, and facet joint osteoarthritis were evaluated on MRI. Spearman correlation and multivariate linear regression analyses were used to examine the factors associated with the severity of LBP (NRS score).

Results

A total of 293 patients (135 male and 158 female, average age 72.6 years) were analyzed. LBP was moderately correlated with buttock and leg pain, and buttock and leg numbness. Significant but weak correlations were observed between LBP and body mass index, appendicular and trunk muscle mass, all domains of SF-36, pelvic tilt, total number of endplate defects and Modic endplate changes, and summary score of disc degeneration grading, but not severity or number of spinal stenoses. In the multivariate regression analysis, age, female sex, trunk muscle mass, diabetes, NRS buttock and leg pain, NRS buttock and leg numbness, SF-36 vitality, pelvic tilt, and total number of endplate defects were associated with the severity of LBP.

Conclusions

Trunk muscle mass, lumbopelvic alignment, and endplate defects, but not severity of stenosis are partly associated with severity of LBP, but buttock and leg pain and buttock and leg numbness have strongest relationships with LBP in patients with LSS.