Purpose
Low back pain (LBP) is the second most common presentation in general practice, with 60-80% of people experiencing it in some formin their lifetime1,2.
The aetiology of one typeof LBPis frompathology of the facet joints (facetogenic LBP), whose synovial capsules are innervatedby the medial branch of the dorsal rami of nerves exiting the spinal canal at the same level as the joint and one level above1.
If conservative management fails, these nerves can be targeted with analgesic injection ormedial branch block. If the joint is...
Methods and materials
This was a prospective study of adult patients enrolled from a single practice over a 2 year period with confirmed facetogenic chronic lower back pain, who had undergonesuccessful bilateralL4/5 and L5/S1RFJD. Success was defined as an improvement in VAS pain scoresof 3 points or greater, or patient satisfaction at 6 weeks post-op. Those patients who had had spinal surgery in the 6 months prior, or who had contra-indications for MRI were excluded from participation.
MRIs wereperformed pre-operatively and at6 and 24 weeks post-op. For each...
Results
Patient Data
There were 23 patients eligible for analysis, comprising of13 females (57%) and10 males (43%) with a mean age of 65 years (range 31-86). All patients had 6-week follow up MRIs and 15 had 24-week scans. All patientsunderwent bilateral RFJD of at least the two levels of interest, with mosthaving denervation at additionallevels. A total of 122 MRI scans were analysed.
Multifidus (MM) Fig. 5 Fig. 6
There was a statistically significant reduction in size of multifidus over the 24 week period in both...
Conclusion
This is the first prospective study in humans of MRI morphology of lumbar paraspinal muscles following clinically successful bilateral RFJD.
Wefound that patients who underwent bilateral RFJD had significant, moderate atrophy of their multifidus muscles by way of total sizeat bothlevels investigatedanda change incomposition at one of the two levels,where musclefibres were replaced with fat. Neither size nor composition of erector spinae was significantly affected by surgery. Degree of spinal canal stenosis, neuroforaminal stenosis, disc and facet joint degeneration had nosignificant effect on degree of...
References
1. Binder DS,Nampiaparampil, DE.The provocative lumbar facet joint. Curr Rev Musculoskelet Med. 2009;2(1):15-24.
2.Freeman MD, Woodham, MA, Woodham AW. The role of lumbar multifidus in chronic low back pain: a review. PM R.2010 Feb;2(2):142-6.
3.Dreyfuss P, Stout A, Aprill C, Pollei S, Johnson B, Bogduk N. The significance of multifidus atrophy after successful radiofrequency neurotomy for low back pain: a review. PM R.2009 Aug;1(8):719-22.
4. Kjaer P, Bendix T, Sorensen J, Korsholm L, Leboeuf-Yde C. Are MRI-defined fat infiltrations in the multifidus muscles associated with...