A recent study 1 mapped the rate of water diffusion in intervertebral discs (IVD) of lower back pain (LBP) patients using MRI and a software program to develop an apparent diffusion coefficient (ADC), or in vivo water proton measurement, shortly after spinal manipulation on the subjects. The results of the study indicate a short-term increase in apparent diffusion could be responsible for the immediate improvements in pain and mobility after a spinal manipulation, though chronic LBP sufferers, whose fissured and ruptured discs allow for more diffusion than typical healthy discs, may be less likely to experience the immediate benefits of mobilization than their acute LBP-suffering counterparts.
Eleven women and five men diagnosed with acute idiopathic LBP were recruited from a physical therapy practice over a six-month period. Their average age was 46 years-old, and they were included in the study based upon a shared complaint of acute LBP or stiffness of a duration less than six weeks, less pain days than non-pain days, with at least one asymptomatic month between the current and previous LBP episodes. Patients were excluded from the study if they suffered from chronic LBP, were resistant to spinal manipulation, had suffered a spinal fracture, felt pain radiating below the knee, previous spinal surgery, had osteoporosis, were pregnant, had any sort of metal implants that might interfere with the MRI machine, suffered from mental health problems, obesity, claustrophobia, substance abuse or cognitive disability.
The subjects received an explanation of the procedure and completed questionnaires about their levels of neuropathy and LBP prior to having their lumbar region scanned via MRI. After the initial scan, a spinal mobilization by an Orthopedic Manual Physical Therapist (OMPT) was performed in an adjacent room, with a scale beneath the OMPT’s feet measuring the weight change during the PA mobilization. Within the hour, another MRI scan was taken of the patients, and they were asked to answer a series of questions to rate their pain and mobility levels, post-treatment. The entire process took roughly 90 minutes per patient.
The images were analyzed visually and through a data software program in relation to each participant’s rate of a water molecule and nutrient diffusion and the sequences of diffusion pre-and post-manipulation. The images were interpreted by a single investigator and radiologist, and the ADC was calculated and verified. Clinical pain and mobility changes were noted and combined with the MRI changes before and after the PA mobilization computations were achieved.
There was a clinically-significant increase in ADC values across all anatomical levels, except for L2-S1 and L2-L3. The biggest changes occurred at L3-L4, and L4-L5. The pain ratings also saw a significant reduction post-mobilization across the subjects after mobilization. These results agree with previous similar study findings, but they offer new insights into acute LBP diffusion and that of older study subjects than in previous studies. Dr. Fryer’s research was referenced in this paper. Click To Tweet The findings of this study may indicate that the phenomenon of mobilization may not be responsible for the improvement of discogenic pain and increased water diffusion, but it is clear that pain, mobility, and diffusion are linked, and mobilization during the acute phases of LBP can temporarily provide increased flow to the IVD, allowing it to expand and decrease pressure and stress on the surrounding nerves. The improved fluid-flow may also help to remove obstructions, irritants, and debris from the IVD, which could also improve function and pain levels, post-manipulation.Mobilization during the acute phases of LBP can temporarily provide increased flow to the IVD, allowing it to expand and decrease pressure and stress on the surrounding nerves. Click To Tweet
Though there was an overall four percent reduction in ADC between typical and slightly degenerated IVDs, the subjects with more severe degeneration had five percent higher levels of diffusion—probably due to fluids collecting in the fissures in the nucleus, created by the disc degeneration. Thus, spinal thrust significantly increased ADC values for those with mild or no degeneration but was less effective in those with more degeneration.
KEYWORDS: Spinal Mobilization Credited to Increased Apparent Diffusion, in vivo water proton measurement, shortly after spinal manipulation, short-term increase in apparent diffusion could be responsible for the immediate improvements in pain and mobility after a spinal manipulation, mobilization during the acute phases of LBP can temporarily provide increased flow to the IVD