Ipsilateral atrophy of paraspinal and psoas muscle in unilateral back pain patients with monosegmental degenerative disc disease

Abstract

Objectives: The aim of this study was to assess the cross-sectional area (CSA) of both paraspinal and psoas muscles in patients with unilateral back pain using MRI and to correlate it with outcome measures. Methods: 40 patients, all with informed consent, with a minimum of 3 months of unilateral back pain with or without sciatica and one-level disc disease on MRI of the lumbosacral spine were included. Patients were evaluated with self-report measures regarding pain (visual analogue score) and disability (Oswestry disability index). The CSA of multifidus, erector spinae, quadratus lumborum and psoas was measured at the disc level of pathology and the two adjacent disc levels, bilaterally. Comparison of CSAs of muscles between the affected vs symptomless side was carried out with Student's t-test and correlations were conducted with Spearman's test. Results: The maximum relative muscle atrophy (% decrease in CSA on symptomatic side) independent of the level was 13.1% for multifidus, 21.8% for erector spinae, 24.8% for quadratus lumborum and 17.1% for psoas. There was significant difference (p,0.05) between sides (symptomatic and asymptomatic) in CSA of multifidus, erector spinae, quadratus lumborum and psoas. However, no statistically significant correlation was found between the duration of symptoms (average 15.5 months), patient's pain (average VAS 5.3) or disability (average ODI 25.2) and the relative muscle atrophy. Conclusion: In patients with long-standing unilateral back pain due to monosegmental degenerative disc disease, selective multifidus, erector spinae, quadratus lumborum and psoas atrophy develops on the symptomatic side. Radiologists and clinicians should evaluate spinal muscle atrophy of patients with persistent unilateral back pain.

Age- and Level-Dependence of Fatty Infiltration in Lumbar Paravertebral Muscles of Healthy Volunteers

“…Conflicting with several studies reporting laterality in healthy individuals, 40 those with LBP, 19,20,27,28 and the general population, 17 we agree with another study 18 in showing no differences between sides or hand/leg dominance in our healthy volunteers. Valentin et al 29 described asymmetry in MF and ES MFI in their healthy subjects, yet no asymmetry for ES volume.…”

“…Women, low lumbar levels, and multifidus muscles were most affected; these findings align with degenerative features of the spinal column that are highly prevalent in asymptomatic individuals. 30 Lumbar paravertebral muscle degeneration occurs in LBP [16][17][18][19][20]24 and in response to induced lesions, 22 yet its prognostic value is unclear. Little is known about normative degeneration, and comparisons with existing literature are limited.…”

“…15 Quantification of degeneration (fat infiltration and atrophy) of lumbar paravertebral muscles has attracted interest in understanding their biologic influence on persistent LBP. Atrophy and fat infiltrates are identified in patients [16][17][18][19][20][21] and following experimentally induced lesions in a porcine model. 22 However, human studies describing lumbar MFI report inconsistent findings: An association with LBP was demonstrated in some 18,[23][24][25][26] but not in others.…”

Role of MRI and ultrasonography in evaluation of multifidus muscle in chronic low back pain patients

“…They found no statistically significant correlation between the duration of symptoms (average 15.5 months), patient's pain (average VAS 5.3) or disability (average ODI 25.2) and the relative muscle atrophy. 18 Farshad et al reviewed MRI scans of 79 patients with symptomatic single level, unilateral, lumbar radiculopathy retrospectively to evaluate if the asymmetry of the multifidus muscle is related to the severity of compression of the nerve root. In 67 recessal and 12 foraminal symptomatic nerve root compressions the CSA ratio did not significantly correlate with the degree of nerve compression.…”

The effect of paraspinal muscles on the lumbar disc herniation

“…We didn't consider the duration of LBP symptomsbasing on the literature that observed the PSM asymmetry was not correlated with duration of symptoms. [18] There have been a few studies searching the morphologic relation of paraspinal muscles with the lumbar disc herniation such as Mattila et al, [19] measured type I and II muscle fibers of multifidus muscle both in post operative lumbar disc herniated patients and control group which was assessed by cadavers. The resulted type II were smaller than the type I muscle fibers and type I fibers had a different appearance.…”