AIM: In the assessment of the lumbar spine by magnetic resonance imaging (M
RI), changes in the paraspinal muscles are frequently overlooked, In this s
tudy, our objective was to investigate the relationships between lumbar mul
tifidus (MF) muscle atrophy and low back pain (LBP), leg pain and inteverte
bral disc degeneration.
METHODS: A retrospective study of 78 patients (aged 17-72) with LBP present
ing with back pain with or without associated leg pain was undertaken, Thei
r MR images were visually analysed for signs of lumbar MF muscle atrophy, d
isc degeneration and nerve root compression. The clinical history in each c
ase was obtained from their case notes and pain drawing charts.
RESULTS: MF muscle atrophy was present in 80% of the patients with LBP, The
correlation between MF muscle atrophy and leg pain was found to be signifi
cant (P < 0.01). However, the relationships between muscle atrophy and radi
culopathy symptoms, nerve root compression, herniated nucleus pulposus and
number of degenerated discs were statistically not significant,
CONCLUSION: Examination of the paraspinal muscles looking for atrophy of MF
muscle should be considered when assessing MR images of lumbar spine, This
may explain the referred leg pain in the absence of other MR abnormalities
. (C) 2000 The Royal College of Radiologists.