L Boissière1, B Moal2, O Gille3, E De-Roquefeuil4, M Durieux4, I Obeid3, V Dousset4, J-M Vital3, W Skalli2. 1. Laboratory of Biomechanics, Arts et Métiers ParisTech, ENSAM, boulevard de l'Hôpital, 75013 Paris, France; Spine Unit 1, Bordeaux University Hospital, place Amélie-Raba-Léon, 33076 Bordeaux, France. Electronic address: boissierelouis@yahoo.fr. 2. Laboratory of Biomechanics, Arts et Métiers ParisTech, ENSAM, boulevard de l'Hôpital, 75013 Paris, France. 3. Spine Unit 1, Bordeaux University Hospital, place Amélie-Raba-Léon, 33076 Bordeaux, France. 4. Neuro-radiology Department, Bordeaux University Hospital, place Amélie-Raba-Léon, 33076 Bordeaux, France.
Abstract
BACKGROUND: Lumbar spinal stenosis is degenerative disc disease most common manifestation. If stenosis degree seems poorly related to symptom severity, lumbar muscles role is recognized. Many studies report imaging methods, to analyze muscle volumes and fat infiltration (FI), but remain limited due to the difficulty to represent entire muscle volume variability. Recently a 3D muscle reconstruction protocol (using the deformation of a parametric specific object method (DPSO) and three-point Dixon images) was reported. It offers the ability to evaluate, muscles volumes and muscle FI. PURPOSE: To describe, in a lumbar spinal stenosis population, muscle volumes, muscle FI and lumbar spinal canal volume with 3D MRI images reconstructions. MATERIALS AND METHODS: Ten adults presenting L4-L5 lumbar stenosis, were included. After specific MRI protocol, three-dimensional, muscle and spinal canal, reconstructions were performed. Muscle (psoas and paraspinal muscles) volumes and fat infiltration (FI), the spinal canal volume, age, and height were correlated one to each other with Spearman correlation factor. An ANOVA was performed to evaluate the intervertebral level influence (P≤0.05). RESULTS: Muscle volumes correlated with height (r=0.68 for psoas). Muscles FI correlated with age (r=0.66 for psoas) and lumbar spinal canal volume (r=0.91). Psoas and paraspinal volumes were maximum at L3-L4 level whereas FI increased from L1-L2 to L5-S1 level. DISCUSSION: These first results illustrate the importance to consider muscles entirely and report correlations between muscles FI, lumbar spinal canal volume and age; and between muscle volumes and patients height. Muscle degeneration seems more related to muscle FI than muscle volume. LEVEL OF EVIDENCE: 3.
BACKGROUND: Lumbar spinal stenosis is degenerative disc disease most common manifestation. If stenosis degree seems poorly related to symptom severity, lumbar muscles role is recognized. Many studies report imaging methods, to analyze muscle volumes and fat infiltration (FI), but remain limited due to the difficulty to represent entire muscle volume variability. Recently a 3D muscle reconstruction protocol (using the deformation of a parametric specific object method (DPSO) and three-point Dixon images) was reported. It offers the ability to evaluate, muscles volumes and muscle FI. PURPOSE: To describe, in a lumbar spinal stenosis population, muscle volumes, muscle FI and lumbar spinal canal volume with 3D MRI images reconstructions. MATERIALS AND METHODS: Ten adults presenting L4-L5 lumbar stenosis, were included. After specific MRI protocol, three-dimensional, muscle and spinal canal, reconstructions were performed. Muscle (psoas and paraspinal muscles) volumes and fat infiltration (FI), the spinal canal volume, age, and height were correlated one to each other with Spearman correlation factor. An ANOVA was performed to evaluate the intervertebral level influence (P≤0.05). RESULTS: Muscle volumes correlated with height (r=0.68 for psoas). Muscles FI correlated with age (r=0.66 for psoas) and lumbar spinal canal volume (r=0.91). Psoas and paraspinal volumes were maximum at L3-L4 level whereas FI increased from L1-L2 to L5-S1 level. DISCUSSION: These first results illustrate the importance to consider muscles entirely and report correlations between muscles FI, lumbar spinal canal volume and age; and between muscle volumes and patients height. Muscle degeneration seems more related to muscle FI than muscle volume. LEVEL OF EVIDENCE: 3.