• Intervention Erector Spinae Stiffness Change [ Time Frame: Change in muscle stiffness immediately after the 30 minute spinal mobilisation intervention. ]
  Stiffness values measured before and after 30 minute spinal mobilisation intervention. Location of muscle assessed by palpation by asking participant to contract lower back muscles and marking the central belly of the muscle. Myometer measurements recorded using handheld device MyotonPRO held over marked area. Recorded 3 times and mean value used for analysis.
• Control Erector Spinae Stiffness Change. [ Time Frame: Change in muscle stiffness immediately after the 30 minute control session (lying still). ]
  Stiffness values measured before and after 30 minute control lying still. Location of muscle assessed by palpation by asking participant to contract lower back muscles and marking the central belly of the muscle. Myometer measurements recorded using handheld device MyotonPRO held over marked area. Recorded 3 times and mean value used for analysis.

• Erector spinae stiffness change, intervention [ Time Frame: Change in muscle stiffness immediately after the 30 minute spinal mobilisation intervention. ]
  Location of muscle assessed by palpation by asking participant to contract lower back muscles and marking the central belly of the muscle. Myometer measurements recorded using handheld device MyotonPRO held over marked area. Recorded 3 times and mean value used for analysis.
• Erector spinae stiffness change, control [ Time Frame: Change in muscle stiffness immediately after the 30 minute control session (lying still). ]
  Location of muscle assessed by palpation by asking participant to contract lower back muscles and marking the central belly of the muscle. Myometer measurements recorded using handheld device MyotonPRO held over marked area. Recorded 3 times and mean value used for analysis.

• Intervention Erector Spinae Tone Change [ Time Frame: Change in muscle tone immediately after the 30 minute spinal mobilisation intervention. ]
  Tone values measured before and after 30 minute spinal mobilisation intervention. Location of muscle assessed by palpation by asking participant to contract lower back muscles and marking the central belly of the muscle. Myometer measurements recorded using handheld device MyotonPRO held over marked area. Recorded 3 times and mean value used for analysis.
• Control Erector Spinae Tone Change [ Time Frame: Change in muscle tone immediately after the 30 minute control session (lying still). ]
  Tone values measured before and after 30 minute control lying still. Location of muscle assessed by palpation by asking participant to contract lower back muscles and marking the central belly of the muscle. Myometer measurements recorded using handheld device MyotonPRO held over marked area. Recorded 3 times and mean value used for analysis.
• Intervention Erector Spinae Elasticity Change [ Time Frame: Change in muscle elasticity immediately after the 30 minute spinal mobilisation intervention. ]
  Elasticity values measured before and after 30 minute spinal mobilisation intervention. Location of muscle assessed by palpation by asking participant to contract lower back muscles and marking the central belly of the muscle. Myometer measurements recorded using handheld device MyotonPRO held over marked area. The device records the logarithmic decrement of the tissue by recording the dissipation of the mechanical energy of the tissue when it recovers shape after deformation. Elasticity is then inversely proportional to the decrement, so a higher decrement value equates to a higher dissipation of mechanical energy and a lower elasticity value. Recorded 3 times and mean value used for analysis.
• Control Erector Spinae Elasticity Change [ Time Frame: Change in muscle elasticity immediately after the 30 minute control session (lying still). ]
  Elasticity values measured before and after 30 minute control lying still. Location of muscle assessed by palpation by asking participant to contract lower back muscles and marking the central belly of the muscle. Myometer measurements recorded using handheld device MyotonPRO held over marked area. The device records the logarithmic decrement of the tissue by recording the dissipation of the mechanical energy of the tissue when it recovers shape after deformation. Elasticity is then inversely proportional to the decrement, so a higher decrement value equates to a higher dissipation of mechanical energy and a lower elasticity value. Recorded 3 times and mean value used for analysis.

• Erector spinae tone change, intervention [ Time Frame: Change in muscle tone immediately after the 30 minute spinal mobilisation intervention. ]
  Location of muscle assessed by palpation by asking participant to contract lower back muscles and marking the central belly of the muscle. Myometer measurements recorded using handheld device MyotonPRO held over marked area. Recorded 3 times and mean value used for analysis.
• Erector spinae tone change, control [ Time Frame: Change in muscle tone immediately after the 30 minute control session (lying still). ]
  Location of muscle assessed by palpation by asking participant to contract lower back muscles and marking the central belly of the muscle. Myometer measurements recorded using handheld device MyotonPRO held over marked area. Recorded 3 times and mean value used for analysis.
• Erector spinae elasticity change, intervention [ Time Frame: Change in muscle elasticity immediately after the 30 minute spinal mobilisation intervention. ]
  Location of muscle assessed by palpation by asking participant to contract lower back muscles and marking the central belly of the muscle. Myometer measurements recorded using handheld device MyotonPRO held over marked area. Recorded 3 times and mean value used for analysis.
• Erector spinae elasticity change, control [ Time Frame: Change in muscle elasticity immediately after the 30 minute control session (lying still). ]
  Location of muscle assessed by palpation by asking participant to contract lower back muscles and marking the central belly of the muscle. Myometer measurements recorded using handheld device MyotonPRO held over marked area. Recorded 3 times and mean value used for analysis.

Various types of spinal manual therapies have been common practice for many years, particularly for treatment of lower back pain. Spinal mobilisation is a specific technique within spinal physiotherapy, often used as a treatment for lower back pain. This is despite limited objective evidence of the effect on muscle tissue quality.

The objective of this study is to measure and analyse the acute effect of a spinal mobilisation intervention on muscle tissue quality in people with lower back pain. The intervention consists of the mobilisation of the lumbar spine for 30 minutes, at a specific rate and pressure. This will be performed by a chartered physiotherapist. This will be tested with 40 participants with lower back pain. This was the recommended sample size given by G Power for a medium effect size, a power of 0.95 and alpha level of 0.05.

Participants will take part in an intervention and a control condition. Lumbar muscle response will be measured for stiffness, tone and elasticity immediately before and after the intervention and the control. The control session consists of lying still for the 30 minutes. Results for both sessions will then be compared. A myometer (MyotonPRO) will be used to assess the change in lumbar muscle objectively. This is a non-invasive, handheld device with many reliability studies on its functionality. Analysis will consider the degree of muscle response with individual covariates involved. This includes gender, height, weight, waist circumference, BMI and level of back pain (discerned by score on Oswestry Disability Index).

The results will compared in 2-way repeated measures, within participant ANOVA for significant differences between conditions and time. Anthropometric measures will be analysed in separate ANOCOVAs to determine any significant factors contributing to level of change.

• Experimental: A - Intervention then control
  Intervention (30 minutes spinal mobilisations) received in first session, then control (30 minutes lying still) received in second session.
  Intervention: Other: Manual spinal mobilisations
• Experimental: B - Control then intervention
  Control (30 minutes lying still) received in first session, then intervention (30 minutes spinal mobilisations) received in second session.
  Intervention: Other: Manual spinal mobilisations

Inclusion Criteria:

• Suffering from lower back pain (region between 12th rib and gluteal folds), acute or chronic.

Exclusion Criteria:

Respond positively to any absolute contraindications for spinal therapy, including:

• segment instability
• infectious disease
• osteomyelitis
• bone tumours
• neurological deficit
• upper motor neuron lesion
• spinal cord damage
• cervical arterial dysfunction

Respond positively to relative contra-indications, excluded based on severity, including:

• osteoporosis
• spinal instability
• rheumatoid arthritis
• inflammatory disease
• active history of cancer
• hypermobile syndrome
• segment hypermobility
• cardiovascular disease
• cervical anomalies
• nerve root disorder
• spinal surgery
• respiratory problems
• thrombosis
• open wounds
• local infection
• fractures or dislocations

• Scottish Hospital Endowments Research Trust
• Pacla Medical Ltd