Research Review By Dr. Ceara Higgins©

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Date Posted:

November 2017

Study Title:

Spinal mobilization vs conventional physiotherapy in the management of chronic low back pain due to spinal disk degeneration: a randomized controlled trial

Authors:

Krekoukias G, Gelalis ID, Xenakis T, et al.

Author's Affiliations:

University of Ioannia, Greece; Technological Education Institute of Central Greece; Technological Educational Institute of Athens, Greece; University of Ioannina School of Medicine, Greece.

Publication Information:

Journal of Manual & Manipulative Therapy 2017; 25(2): 66-73.

Background Information:

Back pain affects 60-80% of the global population at some point (1), and in its chronic form can lead to significant disability (2). Data indicates there is an increased risk of low back pain (LBP) in individuals over 65 years of age, women, individuals with a low level of education, those working in manual labour positions, smokers, and individuals on antidepressant medications (3).

Manual therapy techniques are commonly utilized in the treatment of LBP and can be divided into two main groups: mobilization and manipulation (4). Mobilization is performed within the normal limits of the joint motion in a way that allows them to be stopped by the patient, while manipulation is a rapid movement performed near the end of the range of motion, which generally cannot be controlled by the patient (4).

To date, no randomized controlled trials have been conducted on the efficacy of spinal mobilization in patients with chronic LBP originating from different levels of spinal disc degeneration. This study compared the efficacy of spinal mobilization (MT) with conventional physiotherapy (CP) and sham treatment (ST) in chronic LBP patients with varying degrees of disc degeneration.

Pertinent Results:

The mobilization (MT) and conventional physiotherapy (CP) groups both showed significant improvement in the NPRS, Oswestry, and Roland-Morris, while no improvement was seen in the sham treatment (ST) group. The MT group showed a significantly higher percentage improvement in all areas compared to the other groups. The CP group showed a significantly higher improvement than the ST group in the NPRS and the Roland-Morris, but did not show statistically significant differences on the Oswestry.

In the MT group, there was a positive correlation between the degree of intervertebral disc degeneration and the percentage of improvement on the Oswestry and Roland-Morris questionnaires. No significant correlation in percent improvement was seen in the other two groups on any measure. The CP group showed a moderate negative correlation with intervertebral disc degeneration and improving disability as measured by the Oswestry.

Upon 6-month follow-up, only one subject from the MT group needed to visit a health care professional for further care. In the CP group, 10 subjects had to revisit their health care provider and in the ST group, 21 out of 25 subjects required further help.

Clinical Application & Conclusions:

This study suggests that mobilization leads to the greatest improvements in individuals with LBP and disc degeneration. It has been previously suggested that clinically significant treatment effects are reflected in a minimum improvement in pain levels of 35% (13). In this study, the MT group showed an average improvement in pain of 78.1%, while the CP group only showed average improvements of 16.4%.

The gate theory of pain control posits that spinal mobilization will activate mechanoreceptors in the vertebral joints. The stimulus is then transported by fast myelinated fibers to the posterior horns of the spinal cord, blocking stimuli coming from nociceptors in the same area (14). There is also evidence suggesting that spinal mobilization activates the dorsal periaqueductal grey area of the brain, influencing the perception of pain (15) and that there is a correlation between increased stimulation of the sympathetic nervous system and decreases in the threshold of mechanical pain (16). These combined effects could be responsible for the pain reductions observed in the mobilization group in the current study.

In the MT group, individuals with higher degrees of intervertebral disc degeneration responded more favorably to spinal mobilization (this is a very interesting finding!). Based on the negative correlation found between the degree of spinal degeneration and the level of disability reported on the Oswestry, the authors suggest CP could be effective for managing LBP in individuals with lower levels of disc degeneration (this requires further study). Finally, the number of individuals seeking further treatment after the study was substantially lower in the MT group, suggesting that spinal mobilization may reduce the need for further treatment.

Future research could investigate the efficacy of mobilizing the degenerated segments versus mobilizing the symptomatic segments, as this is more common in clinical practice (9). In addition, future studies could look at the benefits of combining MT with education and exercise, an approach already employed by many practicing clinicians.

Study Methods:

Between January 2013 and September 2014, 75 subjects (42 males and 33 females), between 21 and 78 years of age were recruited from a group of LBP sufferers visiting an orthopedic physician who referred them for physiotherapy. The orthopedic physician performed the initial evaluation using the criteria outlined below.

Inclusion Criteria:
  • Pain in the lumbar spine for a period longer than 3 months’ duration
  • MRI within 12 months of the lumbar region allowing the treating physician to evaluate the grade of the intervertebral disc degeneration according to the modified Pfirrmann scale (7)
Exclusion Criteria:
  • History of spinal surgery
  • History of autoimmune disease
  • History of spondylolysis or spondylolisthesis
  • Spinal fractures
  • Pregnancy
  • Respiratory and/or cardiac pathology
  • History of stroke
  • Cauda equina syndrome
  • Continuous use of pain medications
  • Spinal inflammation
  • Spinal tumour
  • Subjects receiving immunosuppressant medication
  • Use of corticosteroids in the last month
  • Osteoporosis
Subjects were advised not to use pain-controlling medication during the experimental period unless necessary. If pain medications were used, subjects recorded this usage. Subjects would be excluded if they used pain medication continuously or on the day on the interventions.

Subjects were randomly assigned to the MT group, the sham treatment (ST) group, or the CP group, with 25 participants in each group. The MT group received spinal mobilization (passive accessory intervertebral movement and passive physiological intervertebral movements) once a week, for 5 weeks, in a 10-minute session (6) at the levels demonstrating disc degeneration on MRI. A schedule of one session per week was selected for technical reasons, as well as evidence that suggests this frequency shows efficacy in improving pain (6) and disability (8) in individuals with chronic LBP. All interventions were performed by one physiotherapist with 17 years of experience, 12 of which included the application of MT techniques.

The ST group were seen by the same physiotherapist who held their hand in a static position gently touching the skin over the lumbar spine for 10-minutes at the same frequency of one session per week for 5 weeks. No other intervention was applied. When subjects were asked about which group they thought they were in after the end of the experimental period, all the ST subjects believed they were receiving actual treatment (!).

The CP group were also seen by the same physiotherapist, who applied exercises (static stretching of the hamstrings bilaterally for 5 min – 5 sets of 1 min each) (10), TENS applied to the lumbar area (2 channels, biphasic pulse, 90 Hz frequency, 100 ms pulse width, 20 min duration, with the intensity set according to the patient) (11), and Swedish style massage to the lumbar area for 15 minutes (12) at the same schedule of one treatment per week. No home exercises or advice was given.

All patients were asked to complete the numerical pain rating scale (NPRS) as well as the Greek version of the Oswestry, and the Greek version of the Roland-Morris to assess for self-reported disability due to their LBP. All three were completed at baseline and completion of the 5-week experimental period. As well, the physiotherapist contacted all participants 6 months after their final session to evaluate which subjects sought further help from a health care practitioner for their chronic LBP. All subjects completed all treatment sessions and all pertinent evaluations.

Study Strengths / Weaknesses:

Strengths:
  • Using the same physiotherapist for all treatments in the MT and CP groups as well as the ST group helps ensure that the treatments and sham treatment were standardized (yet, this may have introduced some personal ‘technique’ bias from this particular clinician).
Weaknesses:
  • No home exercises or educational programs were provided. Most physiotherapists would have provided these in conjunction with the other components of the standardized care.
  • The use of MRIs that were up to 12 months old could have affected the evaluation of disc degeneration (the nature, degree and levels at which it appears) – things may have changed significantly over that period.
  • Identifying LBP directing stemming from disc degeneration is challenging, as the correlation between the degree of degeneration seen on imaging and clinical symptomatology ids far from perfect.
  • Having the same researcher providing the treatment and collecting the data may have introduced error or bias into the results.

Additional References:

  1. Wong TK, Lee RY. Effects of low back pain on the relationship between the movements of the lumbar spine and hip. Hum Mov Sci 2004; 23: 21-34.
  2. Boscainos PJ, Sapkas G, Stilianessi E, et al. Greek versions of the Oswestry and Roland-Morris disability questionnaires. Clin Orthop Relat Res 2003; 411: 40-53.
  3. Stranjalis G, Tsamandouraki K, Sakas DE, et al. Low back pain in a representative sample of Greek population. Spine 2004; 29: 1355-1360; discussion 1361.
  4. Maitland G, Hengeveld E, Banks K, et al. Maitland’s vertebral manipulation. 6th ed. Oxford: Elsevier Butterworth Heinemann 2005. P.1-15.
  5. Balthazard P, de Goumoens P, River G, et al. Manual therapy followed by specific active exercises versus a placebo followed by specific active exercises on the improvement of functional disability in patients with chronic non specific low back pain: a randomized controlled trial. BMC Musculoskeletal Disord 2012; 13: 1-11.
  6. Goldby LJ, Moore AP, Doust J, et al. A randomized controlled trial investigation the efficacy of musculoskeletal physiotherapy on chronic low back disorder. Spine 2006; 31: 1083-1093.
  7. Griffith JF, Wang Y-XJ, Antonio GE, et al. Modified pfirrmann grading system for lumbar intervertebral disc degeneration. Spine 2007; 32: E708-712.
  8. Rasmussen-Barr E, Nilsson-Wikmar L, Arvidsson I. Stabilizing training compared with manual treatment in sub0acute and chronic low back pain. Man Ther 2003; 8: 233-241.
  9. Slaven E, Goode A, Coronado R, et al. The relative effectiveness of segment specific level and non-specific level spinal joint mobilization on pain and range of motion: results of a systematic review and meta-analysis. J Man Manipulative Ther 2013; 21: 7-17.
  10. Franca FR, Burke TN, Caffaro RR, et al. Effects of muscular stretching and segmental stabilization on functional disability and pain in patients with chronic low back pain: a randomized controlled trial. J Manipulative Physiol Ther 2012; 35: 279-285.
  11. Pivec R, Stokes M, Chitnis AS, et al. Clinical and economic impact of TENS in patients with chronic low back pain: analysis of a nationwide database. Orthopedics 2013; 36: 922-928.
  12. Sritoomma N, Moyle W, Cooke M, et al. The effectiveness of Swedish massage with aromatic ginger oil in treating chronic low back pain in older adults: a randomized controlled trial. Complement Ther Med 2014; 22: 26-33.
  13. Dworkin RH, Turk DC, Wyrwich KW, et al. Interpreting the clinical importance of treatment outcomes in chronic pain clinical trials: IMMPACT recommendations. J Pain 2008; 9: 105-121.
  14. Wyke B, Polacek P. Articular neurology: the present position. J Bone Joint Surg 1975; 57B: 401.
  15. Wright A. Hypoalgesia post-manipulative therapy: a review of potential neurophysiological mechanisms. Man Ther 1995; 1: 11-16.
  16. Vicenzino B, Collins D, Benson H, et al. An investigation of the interrelationship between manipulative therapy-induced hypoalgesia and sympathoexcitation. J Manipulative Physiol Ther 1998; 21: 448-453.