The relationship between radiological paraspinal lumbar measures and clinical measures of sarcopenia in older patients with chronic lower back pain

Psoas Muscle Health is Correlated With Time to Achieve MCID in Patients With Predominant Axial Back Pain Following Decompression Surgery: Early Results

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To determine the impact of psoas muscle health [cross-sectional area (CSA)] on achieving minimal clinically important differences (MCID) in patient-reported outcome measures (PROMs) following laminectomy for patients with predominant back pain (PBP) and leg pain (PLP).

SUMMARY OF BACKGROUND DATA

Psoas muscle health is linked to postoperative outcomes in decompression patients, with MRI-based grading of psoas CSA correlating with these outcomes. However, evidence on its impact on symptomatic recovery, measured by PROMs, is lacking.

METHODS

One hundred six patients with PBP (VAS back > VAS leg) and 139 patients with PLP (VAS leg > VAS back) who underwent laminectomy from 2017 to 2021 were included. Axial T2 MRI images were analyzed for psoas CSA using a validated method. Based on the lowest-quartile normalized total psoas area (NTPA) thresholds, patients were divided into "good" and "poor" muscle health groups. The correlation analyses were performed between the psoas CSA and changes in PROMs. Kaplan-Meier survival analysis was conducted to determine the probability of achieving MCID as a function of time.

RESULTS

Of 106 patients with PBP, 83 (78.3%) had good muscle health, and 23 (21.6%) had poor muscle health. Of 139 patients with PLP, 54 (38.8%) had good muscle health, and 85 (61.1%) had poor muscle health. In the PBP group, older age was associated with poor muscle health (69.70±9.26 vs . 59.92±15.01, P =0.0002). For both cohorts, there were no differences in the rate of MCID achievement for any PROMs between the good and poor muscle health groups. In the PBP group, Kaplan-Meier analysis showed patients with good psoas health achieved MCID-VAS back and Oswestry Disability Index (ODI) in median times of 14 and 42 days ( P =0.045 and 0.015), respectively.

CONCLUSION

Good psoas muscle health is linked to faster attainment of MCID, especially in patients with PBP compared with PLP after decompression surgery.

LEVEL OF EVIDENCE

III.

The cross-sectional area of gluteal muscle on multiaxial CT scan as a predictor for diagnosing sarcopenia in patients with degenerative lumbar disease

PURPOSE

This study examined the predictive value of the gluteal muscle index (GMI) for diagnosing sarcopenia in patients with degenerative lumbar disease (DLD), highlighting the need for effective diagnostic markers in this population.

METHODS

This prospective observational study included 202 elderly patients scheduled for lumbar spine surgery. Muscle indices for psoas, paraspinal, and gluteal muscles were measured using multiaxial computed tomography. Sarcopenia was diagnosed per the 2019 Asian Working Group for Sarcopenia (AWGS) criteria. Statistical analysis comprised univariate and multivariate logistic regression to identify predictors of sarcopenia.

RESULTS

Of patients, 77% were diagnosed with sarcopenia. The GMI and psoas muscle index (PMI) were identified as significant predictors of sarcopenia in the univariate analysis. Multivariate analysis confirmed their predictive value, with higher indices correlating with a reduced risk of sarcopenia (GMI odds ratio [OR] = 0.95, 95% confidence interval [CI] = 0.92-0.97; PMI OR = 0.95, 95% CI = 0.92-0.98, both P < .001).

CONCLUSION

The GMI serves as a reliable predictor of sarcopenia in elderly patients undergoing lumbar spine surgery for DLD, suggesting a significant role of gluteal muscles in diagnosing sarcopenia. Incorporating GMI into clinical assessments is critical to better manage and diagnose sarcopenia in this population.

Spine-specific sarcopenia: distinguishing paraspinal muscle atrophy from generalized sarcopenia

BACKGROUND CONTEXT

Atrophy of the paraspinal musculature (PM) as well as generalized sarcopenia are increasingly reported as important parameters for clinical outcomes in the field of spine surgery. Despite growing awareness and potential similarities between both conditions, the relationship between "generalized" and "spine-specific" sarcopenia is unclear.

PURPOSE

To investigate the association between generalized and spine-specific sarcopenia.

STUDY DESIGN

Retrospective cross-sectional study.

PATIENT SAMPLE

Patients undergoing lumbar spinal fusion surgery for degenerative spinal pathologies.

OUTCOME MEASURES

Generalized sarcopenia was evaluated with the short physical performance battery (SPPB), grip strength, and the psoas index, while spine-specific sarcopenia was evaluated by measuring fatty infiltration (FI) of the PM.

METHODS

We used custom software written in MATLAB® to calculate the FI of the PM. The correlation between FI of the PM and assessments of generalized sarcopenia was calculated using Spearman's rank correlation coefficient (rho). The strength of the correlation was evaluated according to established cut-offs: negligible: 0-0.3, low: 0.3-0.5, moderate: 0.5-0.7, high: 0.7-0.9, and very high≥0.9. In a Receiver Operating Characteristics (ROC) analysis, the Area Under the Curve (AUC) of sarcopenia assessments to predict severe multifidus atrophy (FI≥50%) was calculated. In a secondary analysis, factors associated with severe multifidus atrophy in nonsarcopenic patients were analyzed.

RESULTS

A total of 125 (43% female) patients, with a median age of 63 (IQR 55-73) were included. The most common surgical indication was lumbar spinal stenosis (79.5%). The median FI of the multifidus was 45.5% (IQR 35.6-55.2). Grip strength demonstrated the highest correlation with FI of the multifidus and erector spinae (rho=-0.43 and -0.32, p<.001); the other correlations were significant (p<.05) but lower in strength. In the AUC analysis, the AUC was 0.61 for the SPPB, 0.71 for grip strength, and 0.72 for the psoas index. The latter two were worse in female patients, with an AUC of 0.48 and 0.49. Facet joint arthropathy (OR: 1.26, 95% CI: 1.11-1.47, p=.001) and foraminal stenosis (OR: 1.54, 95% CI: 1.10-2.23, p=.015) were independently associated with severe multifidus atrophy in our secondary analysis.

CONCLUSION

Our study demonstrates a low correlation between generalized and spine-specific sarcopenia. These findings highlight the risk of misdiagnosis when relying on screening tools for general sarcopenia and suggest that general and spine-specific sarcopenia may have distinct etiologies.

Comparison Between the Clinical Effect of Percutaneous Kyphoplasty for Osteoporosis Vertebral Compression Fracture Patient with or Without Sarcopenia: A Retrospective Cohort Study

Background

Sarcopenia and osteoporosis vertebral compression fractures (OVCF) are common diseases that increase with age. This study aimed to investigate the effects of sarcopenia on OVCF patients after percutaneous kyphoplasty (PKP).

Methods

Data of 101 patients who were treated with single-level PKP between January 2021 and March 2022 at Ningbo No.6 Hospital were enrolled. Forty-five OVCF patients with sarcopenia who met our inclusion criteria were included in the Sarcopenia-PKP group (SPKP group), and 56 patients in the Normal-PKP group (NPKP group). All clinical and radiological data were collected from medical records. Baseline characteristics, operation-related parameters (operation time, time to ambulation, hospital stay, surgery segment), clinical outcomes (visual analog score [VAS], Oswestry Disability Index [ODI], Japanese Orthopaedic Association Scores [JOA] of lumber), radiological outcomes (vertebral anterior height rate and local kyphosis angle), Macnab score, and complications were evaluated and compared.

Results

There were no significant differences in age, sex, surgical segment preoperative VAS score, ODI, or JOA between the two groups (P > 0.05). The SPKP group had a significantly lower body mass index (BMI), bone mineral density (BMD), and smooth muscle index (SMI) than the NPKP group (P < 0.05). Significantly longer hospital stays and time to ambulation in SPKP group than NPKP group (3.7±0.8 vs 3.4±0.5 and 2.0±0.8 vs 1.6±0.5, P < 0.05). In SPKP group, significantly better clinical outcomes at 6- and 12-months follow-up were observed in NPKP group than SPKP group (P < 0.05), and NPKP group showed significantly better in vertebral anterior height rates than SPKP group after 6-month follow-up (P < 0.05). Moreover, there were significantly more cases of complications in the SPKP group (P < 0.05).

Conclusion

Sarcopenia could reduce the clinical effect of percutaneous kyphoplasty, and furthermore. Related studies are needed to verify the effect of sarcopenia on OVCF patients.