Goal attainment scaling as a measure of treatment success after physiotherapy for chronic low back pain.

OBJECTIVES: In some chronic conditions, patient-specific tools with individualized items have proved to be more sensitive outcome instruments than fixed-item tools; their use has not yet been investigated in chronic low back pain (cLBP). METHODS: Eleven males and 21 females [mean age 44.0 (12.3) years] with cLBP, undergoing a spine-stabilization physiotherapy programme, completed the Roland Morris (RM) Disability Scale and a 0-10 pain scale pre- and post-therapy. Post-therapy, goal attainment scaling (GAS) scores were calculated regarding achievement of 2-6 priority GAS goals established pre-therapy; global outcome of therapy was assessed on a 5-point Likert scale. RESULTS: Approximately one-fifth of the individualized goals were not covered by items of the RM. Of the 121 individualized goals, 41 (34%) were achieved at the expected level, 42 (35%) were exceeded and 38 (31%) were not reached. GAS scores correlated with change scores for pain (r = 0.61, P < 0.0001) and RM (r = 0.49, P = 0.006). Sixty-five per cent of the patients had a successful outcome according to GAS (i.e. a score >or=50); 55%, according to global outcome (therapy helped/helped a lot); 39%, according to the RM score change (score decrease >or=30%); and 44%, according to the pain score change (score decrease >or=30%). CONCLUSIONS: GAS demonstrates the achievement of important goals undetected by fixed-item measures and is a valid and sensitive outcome measure for assessing the success of rehabilitation in patients with cLBP.

Spinal segmental stabilisation exercises for chronic low back pain: programme adherence and its influence on clinical outcome.

Exercise rehabilitation is one of the few evidence-based treatments for chronic non-specific low back pain (cLBP), but individual success is notoriously variable and may depend on the patient's adherence to the prescribed exercise regime. This prospective study examined factors associated with adherence and the relationship between adherence and outcome after a programme of physiotherapeutic spine stabilisation exercises. A total of 32/37 patients with cLBP completed the study (mean age, 44.0 (SD = 12.3) years; 11/32 (34%) male). Adherence to the 9-week programme was documented as: percent attendance at therapy, percent adherence to daily home exercises (patient diary) and percent commitment to rehabilitation (Sports Injury Rehabilitation Adherence Scale (SIRAS)). The average of these three measures formed a multidimensional adherence index (MAI). Psychological disturbance, fear-avoidance beliefs, catastrophising, exercise self-efficacy and health locus of control were measured by questionnaire; disability in everyday activities was scored with the Roland-Morris disability scale and back pain intensity with a 0-10 graphic rating scale. Overall, adherence to therapy was very good (average MAI score, 85%; median (IQR), 89 (15)%). The only psychological/beliefs variable showing a unique significant association with MAI was exercise self-efficacy (Rho = 0.36, P = 0.045). Pain intensity and self-rated disability decreased significantly after therapy (each P < 0.01). Adherence to home exercises showed a moderate, positive correlation with the reduction in average pain (Rho = 0.54, P = 0.003) and disability (Rho = 0.38, P = 0.036); higher MAI scores were associated with greater reductions in average pain (Rho = 0.48, P = 0.008) and a (n.s.) tendency for greater reductions in disability (Rho = 0.32, P = 0.07) Neither attendance at therapy nor SIRAS were significantly related to any of the outcomes. The benefits of rehabilitation depended to a large extent on the patient's exercise behaviour outside of the formal physiotherapy sessions. Hence, more effort should be invested in finding ways to improve patients' motivation to take responsibility for the success of their own therapy, perhaps by increasing exercise self-efficacy. Whether the "adherence-outcome" interaction was mediated by improvements in function related to the specific exercises, or by a more "global" effect of the programme, remains to be examined.

Muscle thickness changes during abdominal hollowing: an assessment of between-day measurement error in controls and patients with chronic low back pain.

Spine stabilization exercises, in which patients are taught to perform isolated contractions of the transverses abdominus (TrA) during "abdominal hollowing", are a popular physiotherapeutic treatment for low back pain (LBP). Successful performance is typically judged by the relative increase in TrA thickness compared with that of the internal (OI) and external (OE) oblique muscles, measured using ultrasound. The day-to-day measurement error (imprecision) associated with these indices of preferential activation has not been assessed but is important to know since it influences the interpretation of changes after treatment. On 2 separate days, 14 controls and 14 patients with chronic LBP (cLBP) performed abdominal hollowing exercises in hook-lying, while M-mode ultrasound images superimposed with tissue Doppler imaging (TDI) data were recorded from the abdominal muscles (N = 5 on each side). The fascial lines bordering the TrA, OI and OE were digitized, and muscle thicknesses were calculated. The between-day error (intra-observer) was expressed as the standard error of measurement, SEM; SEM as a percentage of the mean gave the coefficient of variation (CV). There were no significant between-day differences for the mean values of resting or maximal thickness for any muscle, in either group (P > 0.05). The median SEM and CV of all thickness variables was 0.71 mm and 10.9%, respectively for the controls and 0.80 mm or 11.3%, respectively for the cLBP patients. For the contraction ratios (muscle thickness contracted/thickness at rest), the CVs were 3-11% (controls) and 5-12% (patients). The CVs were unacceptably high (30-50%, both groups) for the TrA preferential activation ratio (TrA proportion of the total lateral abdominal muscle thickness when contracted minus at rest). In both the controls and patients, the precision of measurement of absolute muscle thickness and relative change in thickness during abdominal hollowing was acceptable, and commensurate with that typical of biological measurements. The TrA preferential activation ratio is too imprecise to be of clinical use. Knowledge of the SEM for these indices is essential for interpreting the clinical relevance of any changes observed following physiotherapy.

Tissue Doppler imaging for detecting onset of muscle activity.

Tissue Doppler imaging (TDI) is typically used to image and quantify tissue motion. We investigated whether this method would serve as a viable alternative to surface electromyography (EMG) in providing a reliable and valid measure of the onset of muscle activity. Ten healthy subjects performed maximal knee extension exercises at 0 degrees /s (isometric), 60 degrees /s, 120 degrees /s, 180 degrees /s, and 240 degrees /s (5 times each, on each side), using an isokinetic dynamometer. Simultaneous EMG and TDI velocity (superimposed on motion-mode ultrasound cine-loops) recordings were made from vastus lateralis. All tests were repeated 1 week later. There was a good correlation between the onset times determined with TDI velocity and EMG: r = 0.78 (day 1), and r = 0.80 (day 2) (each P < 0.001). The mean difference (and SD) in muscle onset time between the two methods (TDI minus EMG) was -20.3 +/- 31.0 ms (day 1) and -17.4 +/- 27.2 ms (day 2). TDI represents a reliable and valid measure of detecting onset of muscle activity. The mean difference between EMG and TDI onset times (approximately 20 ms) is likely explained by electromechanical delay. TDI represents a viable method for measuring the onset of muscle activity; it may offer a non-invasive alternative to fine-wire EMG for use with small or deep muscles.