Spinal Traction/Decompression
Who Benefits?
Recently CBC Market Place aired a controversial story regarding the effectiveness of non-surgical spinal decompression therapy. Claims have been made that this is a safe and 86-90% effective treatment for lumbar disc pathology. However, when Dwain reviewed the literature, he found the studies quoted had small sample sizes, randomization was compromised and descriptive statistics were lacking. In the past, most randomized control studies looking at the effect of mechanical lumbar traction on subjects with generalized “low back pain” have not shown a favourable outcome. Furthermore, Deen documented a case study describing a sudden progression of a lumbar disc herniation during one of these treatments, bringing safety into question.
What to do with such confounding information when clinically, we see some of our patients do benefit from traction? Spine has recently published a quality study which suggests that a sub-group of “low back pain” sufferers exists who will likely benefit from this treatment option. Fritz has found that this subgroup is characterized by:
- The presence of leg symptoms
- Signs of nerve root compression (myotome, dermatome, reflex)
- Peripheralization of symptoms down the lower extremity with lumbar extension movements
- Positive crossed straight leg raise (SLR on unaffected side reproduces symptoms on affected side)
Interestingly, he found that last two characteristics were the most statistically significant and often correlate to complex disc pathology with poor surgical outcomes.
The above study provides clinical prediction guidelines to assist clinicians in determining when a client will most likely benefit from spinal traction.
(Example of manual traction to L4/5)
A variety of different spinal traction methods exist:
- Manual (Try pulling on your patients legs to create traction - if pain is decreased then the odds of a favourable outcome are increased)
- Gravity assisted (Guevenol found no significant difference between inverted spinal traction and conventional traction)
- Mechanical Includes conventional traction and non-surgical decompression
Proposed benefits from mechanical traction include:
- widening of intervertebral disc space and vacuum effect, decreasing intra-disc pressure allowing migration of herniated disc material
- stretching of intervertebral ligaments (specifically the posterior longitudinal ligament and annular fibers) and paravertebral muscles
- widening of intervertebral or neural foramina
- returning of intervertebral joints to their normal former position
- straightening spinal curves
When assessed via CT Scan, Sari found the most statistically significant benefits in the cervical spine occurred at the C5/6 level on a median disc bulge versus postero-lateral or paramedian disc bulges. The effects were most significant on the central canal space versus facet joint space, neural foraminal spaces or thickness of flaval ligaments.
Further quality research is required to refine the clinical prediction rules for traction in the lumbar spine and to establish these same rules in the cervical and thoracic spines. Additional study of parameters regarding frequency, duration, mode (static vs intermittent) and magnitude of force will enhance the application of this treatment to our patients.
REFERENCES
Deen G, Rizzo T, Fenton D. Case Report: Sudden Progression of Lumbar Disk Protrusion During Vertebral Axial Decompression Traction Therapy. Mayo Clin Proc, 2003, 78: 1554-1556.
Dwain, D. Non-surgical spinal decompression therapy: does the scientific literature support efficacy claims made in the advertising media? Chiropr Osteo, 2007; 15:7.
Fritz J, Weston L, Matheson J, Brennan G, Hunter S, Moffit S, Swalberg A, Rodriquez B. Is there a Subgroup of Patients With Low Back Pain Likely to Benefit From Mechanical Traction? Results of a Randomized Clinical Trial and Subgrouping Analysis. Spine, 2007; 32(26): 793-800.
GuEvenol K, TuEzuEn C, Peker O, GoEktay T. A comparison of inverted spinal traction and conventional traction in the treatment of lumbar disc herniations. Physiotherapy Theory and Practice, 2000; 16: 151-160.
Sari H, Akarirmak U, Karacan I, Akman H, Evaluation of Effects of Cervical Traction on Spinal Structures by Computerized Tomography. Advances in Physiotherapy, 2003; 5: 11-121.