1 PAPER TITLE The Wellington Education and Self Treatment (WEST) Chronic Lower Back Pain (CLBP) trial Principal Contact: Dr Giresh Kanji Level 2, 354 Lambton Quay Wellington dr.kanji@xtra.co.nz Background: Despite the plethora of studies on non specific chronic low back pain (NSCLBP), the most common musculoskeletal pain complaint, there still seems to be no real consensus or evidence base to suggest what is the most effective option for helping the 80% of the population that will suffer from NSLBP at some stage in their lives. Furthermore in 5 to 10% of cases the pain does not abate and the severity of the NSLBP has a significant effect on the quality of life of these patients, leading to worsening pain and psychosocial difficulties due to central sensitisation and secondary effects on mood. Disc pain is the most common source of pain in the lumbar spine. For practitioners treating low back pain consistent patterns emerge whereby increasing pressure on the discs such as when lifting, bending, sitting for long periods, coughing and sneezing are known to be triggers for low back pain. It may follow that if pressure aggravates symptoms from the lumbar spine then postural advice on reducing loading on the lumbar spine discs and distraction of the discs may be helpful to alleviate pain and reduce future exacerbations. From the past two years experience in recommending tilt-table inversion in my practice, the number of epidural injections (both caudal and transforaminal) has reduced by over 95% and in 2013 the number of transforaminal steroids performed was under 6. There have also been no patients seen in the clinic requiring a discectomy in the past 12 months, despite several large disc protrusions and extrusions diagnosed on MRI scan in my pain practice. Many patients have bought inversion tables for the workplace and perform intermittent inversion and have managed to stay working in their manual occupations. Studies of inversion have generally used small numbers, and this form of treatment is largely ignored by most professions treating low back pain. Many randomised control trials however show significant clinical benefits, although these are not always statistically significant.
2 When treating lower back pain clinically important changes are defined as the minimum change where a the patient perceives a benefit. Hagg et al. 1 studied 289 low back pain patients and found the clinically significant change in pain measured by visual analogue score to be 18-19/100. A clinically significant change in Owestry Disability Index (ODI) was found to be 10. Sheffield 2 performed a case series of 175 people who were off work due to low back and leg symptoms. After setting up a primitive inversion machine 155 patients returned to work after inversion. An RCT 3 was performed to test 30 degrees versus 60 degrees of inversion and found that 60 degrees was only slightly better than 30 degrees. Forty seven women were randomised to three groups supine, inversion -30 degrees and -60 degrees. Each group performed three minutes inversion three times for four days a week for eight weeks. Pain reduced in the supine group from 5.73 +/- 1.53 to 3.73+/- 1.53, the -30 degree inversion group from 5.78 +/-1.52 to 2.22 +/- 0.81 and the -60 degree inversion group from 5.57 +/- 1.34 to 2.14+/- 0.66 (p=.009).other parameters measured such as night pain, drug relief, stiffness, walking freedom, walking discomfort, standing still, twisting, sitting in a hard chair and soft chair all showed clinically and statistically significant improvements in the inversion groups. An RCT of 24 people awaiting discectomy for disc prolapse compared physiotherapy to physiotherapy plus inversion 4. The inversion group experienced a 77% reduction in discectomy rate. Furthermore the VAS pain scores reduced from 3.2 to 0.9 (t-test p = 0.078) for the inversion group and increased from 2.8 to 3.0 in the control group. The ODI reduced from 50 (22-78) to 31 (14-74) in the inversion group and increased from 48 (38-56) to 54 (32-56) in the control group. The authors stated that the economic impact from this study was savings in excess of 100 million pounds per year. In New Zealand discectomy costs approximately $15 000.00 versus $200.00 for a home inversion machine. Although the study recruited small numbers the results were impressive. Although many RCTs show a positive benefit of inversion therapy for low back pain larger trials need to substantiate the research hence the requirement to perform the WEST inversion trial for chronic low back pain. Question/problem: The primary goal of this trial is to see whether a six week trial of home based inversion therapy results in a statistically and clinically significant decrease in low back pain as measured by the numerical pain rating scale. Secondary measures in the trial will include Owestry Disability Index (ODI ), Roland Morris Disability Index (RMDI) and Short Form 36
3 (SF-36). Significance: Proposed design: An RCT with large numbers of participants will improve the literature available on inversion therapy. Randomised control trial with crossover at the end of six weeks if intervention group has a statistically and clinically significant improvement in NPRS (/10). Using a power of 80%, a standard deviation of 2.7 and a difference of 1.5 on the NPRS a sample size of 51 would be required in each group. The trial will have ethical approval from Health and Disability Ethics Committees (HDEC). The study population will be those with low back pain for over six months duration. The participants will be required to travel to a clinic for an initial and final assessment. All participants will complete the final and initial questionnaires including all the measurement instruments. The participants will be screened by the principal investigator of this trial to ensure that they meet the inclusion/exclusion criteria for the trial. The two groups will be inversion plus usual care versus usual care. The intervention group will perform self directed inversion at home once a day taking approximately ten minutes. All participants will give informed consent to participate in the trial. The participants will not be remunerated for their time. It is been recommended by the statisticians at Massey University that, in order to be powerful enough to produce significantly results, there needs to be 40-50 participants in each group. Inclusion Criteria lower back pain over a period of 6 months or longer 18 to 60 years of age of either gender Exclusion Criteria Cauda equina syndrome Cancer Prior lumbar surgery Scoliosis greater than 15 degrees Vertebral fractures, spine infection or tumour, Inflammatory spondyloarthropathy Pregnant or attempting to become pregnant Greater than 80% disk narrowing (as measured on MRI scan, X- Ray). History of stroke
4 Unstable blood pressure Requiring a mobility aid other than 1 walking stick Current hip osteoarthritis or hip injury Sacroiliac joint pathology Weight greater than 130kg Method Once ethics committee approval has been gained advertising will occur in local newspapers, letters to health professionals treating low back pain to recruit participants. An investigator will contact all those interested in participating in the trial to perform phone screening. A checklist will be used to record the participants details, medical history, and to check entry criteria. Eligible participants will be sent an appointment for the initial consultation. A statistician will provide envelopes for the investigator to randomly allocate participants in the trial. A nurse clinician will perform the consultations collecting history of the low back complaint, including investigations, treatment and medications as well as impact on daily life. Group A will be advised they are the control group, why a control group is important and that if the intervention group performs better than the control group they will be invited to have the intervention treatment once the trial concludes. Once randomised, the nurse clinician will demonstrate to the participant their particular arm of the trial, and answer any questions that the participant may have. The participants will then be given a full written description of the methods relating to their particular arm of the trial and the clinician will also be available to help explain and answer any questions to ensure all participants are happy with the procedure. At 3 month and 12 month follow-up, the participants will be requested to complete the same questionnaires. Inversion Therapy (Intervention group) Participants in the inversion group will be advised to continue whatever usual care they are performing (physio, medications, doctors visits etc). The tilt table will be slowly tilted back (at a speed as per each individuals tolerance) to 45 degrees head down position. The
5 inversion will be intermittent with three two minute inversions performed with 10 to 30 seconds break between each inversion. The total time will be approximately 7 to 9 minutes. Usual Care Participants in the usual care group will be advised to continue whatever usual care they are performing (physio, medications, doctors visits etc). Statistical analysis of the results will be completed by Gordon Purdie, biomedical statistician, Otago University, Wellington. Trial design and documentation to date have been written by Pat Hogan under supervision by Dr Giresh Kanji. This trial is being supervised by Dr Giresh Kanji (Musculoskeletal Pain Specialist) and Rachel Page (Associate Professor, Massey University). Justification: A randomised control trial will enable us to compare the direct effects of inversion therapy to usual care as this is the only difference between the two groups. References: 1. Hagg, O., Fritzell, P.,& Nordwall, A. (2003). The clinical importance in outcome scores after treatment of chronic low back pain. Eur Spine J. 12 :12 20. 2. Sheffield 3. Kim, JD, Oh, H., Lee J, Ko, I,& Jee, Y.(2013). The effect of inversion traction on pain sensation, lumbar flexibility and trunk muscles strength in patients with chronic low back pain. Isokinetics and Exercise Science 21. 237-246. 4. Prasad, K.S., Gregson, B.A., Hargreaves, G., Byrnes,T.,Winburn, P.,Mendelow, A.D (2012). Inversion Therapy in Patients with Pure Single Level Lumbar Discogenic Disease: A Pilot Randomized Trial. Disability & Rehabilitation, 34(17), 1473-1480.