Table 1 Inclusion and exclusion criteria for the non-specific chronic low back pain (NSCLBP) group

• Aged 18–65 years

• History of chronic LBP (> 12 weeks)

• Pain in the lumbar and/or buttock region (defined as pain reported below the level of T12 and no lower than the buttock line)

• Clear mechanical basis of the disorder aligned with specific aggravating and easing postures and movements, with distinct symptom relief observed during movement conducted in the opposing direction of reported pain provocation (assessed subjectively and objectively)

• Clinical diagnosis of specific MCI - either FP or AEP

• Signs of serious spinal pathology (Red flags) including significant trauma, unexplained weight loss and widespread neurologic changes

• Any vestibular, visual or neurological dysfunction affecting balance

• Current radiating symptoms (and/or neurological deficit) below the level of the buttock crease

• Current pregnancy or breastfeeding

• History of spinal surgery, fracture or malignancy

• Inability to perform any of the functional tasks unaided

• Inability to read written English language documents and follow verbal instructions in English

• Not fulfilling the inclusion criteria