A randomized clinical trial of treatment for lumbar segmental rigidity.

STUDY DESIGN: A randomized single-blind clinical trial of facet injections plus exercise, versus exercise alone, in chronic disabling work-related lumbar spinal disorders (CDWRLSD), accompanied by pilot interrater reliability and facet syndrome prevalence studies. OBJECTIVES: To systematically investigate the use of facet injections as an adjunct to supervised lumbar stretching exercises in regaining lumbar range of motion (ROM) following prolonged deconditioning after work-related lumbar injuries. To assess interrater reliability of visual assessment of segmental rigidity (SR), and to evaluate the prevalence of facet syndrome in cases of lumbar SR. SUMMARY OF BACKGROUND DATA: Corticosteroid joint injections have often been used to reduce musculoskeletal inflammation to facilitate joint mobilization in the presence of degenerative arthritis. Lumbar segmental rigidity is a recently described entity usually associated with painful chronic spinal disorders and postoperative spine surgery. Previous work has shown that SR and lumbar ROM improves with a brief intervention consisting of facet injections followed by specific stretching exercises. No systematic study has investigated the potential benefits of a combination of facet injections and exercise over supervised exercises alone to treat lumbar SR. Similarly, no study has assessed the association between SR and the facet syndrome. METHODS: From a group of consecutive patients (n = 421) with CDWRLSD referred for tertiary rehabilitation between November 1999 and January 2001, 70 were noted to have SR on intake physical examination. The first part of this study assessed interrater reliability for detecting SR, and intrarater reliability for 3-segment true lumbar ROM measurements. Patients randomly assigned to participate in supervised stretching exercises with the addition of fluoroscopically guided bilateral facet injections at the involved levels (Group A, n = 36) also underwent facet syndrome prevalence assessment at the time of injection. They were compared to a randomly allocated comparison group (Group B, n = 34) undergoing exercises alone in a single-blind design. Physical therapists saw patients an average of twice per week, providing supervision of a progressive home stretching program. Inclinometric joint ROM was measured at the time of group allocation, and again 5 to 7 weeks later. Validated questionnaires of pain (intensity VAS) and disability (Million VAS) related to the CDWRLSD were provided before and after the interventions. RESULTS: Part 1 reliability and facet syndrome prevalence work revealed that interrater reliability for experienced examiners to detect rigid segments was excellent (Pearson's r = 0.97, P < 0.01). Intrarater 3-joint motion measurement reliability was also good for all sagittal/coronal ROM (Pearson's r = 0.95-0.99, P < 0.01). Only 5 of 29 subjects with SR met criteria for facet syndrome (17%), consistent with prior prevalence studies of unselected patients with low back pain. In Part 2, a large majority of patients in both groups improved from the initial to the post-treatment ROM measurements (the primary outcome criterion of the study). However, a higher proportion of Group A (injection) patients (87%-95%) showed ROM improvement, compared to Group B (exercise only) patients (64%-79%). Group A patients showed a significantly greater ROM improvement in all sagittal and coronal movements, both in absolute terms and percent of initial measurement. No significant differences in pain or disability self-report were found between groups, pre- or postintervention, but both groups showed significant improvement from pre- to postintervention in pain and disability assessments. CONCLUSIONS: The detection of SR and measurement of 3-segment true lumbar ROM by experienced examiners is highly reliable. Only 17% of CDWRLSD patients with lumbar SR met criteria for the facet syndrome, a rate approximately equal to that of unselected low back pain cohorts. This indicates that lumbar SR may be found whether or not pain of facet joint origin is present. In the randomized trial, facet injections significantly increased the percentage of patients with SR showing ROM improvement, as well as the degree of improvement in lumbar mobility after treatment. There is no evidence that facet injections increase the improvements in pain/disability report noted in both groups.

Relevance of aerobic capacity measurements in the treatment of chronic work-related spinal disorders.

STUDY DESIGN: Prospective cohort study of rehab program completers, comparing aerobic capacity data of chronic lumbar spinal disorder patients (CLSD) to that of chronic cervical spinal disorder (CCSD), collected from a tertiary care facility. OBJECTIVE: We evaluated whether CLSD is associated with different pre- and postrehabilitation aerobic capacity deficits than CCSD, and whether such deficits affect functional restoration outcomes. SUMMARY OF BACKGROUND DATA: Chronic spinal disorder patients are thought to lose aerobic fitness as a component of the deconditioning syndrome. Patients with CLSD often restrict aerobic activities because of back or leg pain, while CCSD patients generally do so to a lesser degree. We hypothesized that those with CLSD would have greater deficits in tests of aerobic fitness than patients with CCSD both before and after treatment. METHODS: From a consecutive cohort of 683 patients with work-related spinal disorders, two groups were identified: patients with CLSD (n = 504; age 40.1 years; 68% male); and patients with CCSD (n = 179; 41.3 years; 43% male). All patients completed an intensive, medically supervised functional restoration program. Before and after the program, patients completed a submaximal bicycle ergometer aerobic capacity test and a psychosocial test battery. A structured clinical interview to determine socioeconomic outcomes was conducted 1 year after the program completion. RESULTS: Of CLSD patients 33% and 11% of CCSD patients (P < 0.001) either failed to produce any torque or could not complete at least 2 stages on the bicycle on preprogram tests (invalid tests). However, all patients had valid bicycle tests at program completion. Nearly two-thirds of the subjects with initially invalid tests in the lumbar group failed to develop any torque, while only one-third of subjects with invalid tests of the cervical group had a similar result. Thus, CLSD is associated with greater prerehabiliation aerobic fitness deficits than CCSD. Overall, there was no significant change in pre to postrehab aerobic capacities for the initially valid test subjects. The initially invalid test subjects achieved similar postrehabilitation scores compared to the valid test subjects, although CLSD patients with initially valid tests performed slightly better at the posttest. Socioeconomic outcomes were the same one year after the program for valid and invalid test subjects. CLSD patients had higher preprogram self reports of disability. The subgroup of the initially invalid test subjects that produced no torque whatsoever (19.3% of CLSD and 3.9% of CCSD) did not differ from the subgroup that failed to complete 2 stages in the pretest of aerobic performance on depression. They had higher pretest self-reported disability. CONCLUSIONS: Although mean aerobic fitness levels for all patients improved during rehabilitation, the improvement is almost entirely accounted for by initially invalid tests becoming valid. Aerobic capacity testing measured with submaximal bicycle ergometry may frequently be invalid when fear-avoidance limits effort, particularly in CLSD. Psychosocial fear-avoidance, as it applies to bicycle ergometry, can be overcome in virtually all patients motivated to complete a tertiary rehabilitation program. As such, prerehabilitation aerobic capacity testing is a poor differentiator of postrehabilitation outcomes.

Quantifying the lumbar flexion-relaxation phenomenon: theory, normative data, and clinical applications.

STUDY DESIGN: A two-part investigation was conducted: 1) a prospective study of asymptomatic subjects quantitatively comparing trunk mobility to surface electromyographic (sEMG) signals from the erector spinae during trunk flexion; and 2) a prospective repeated-measures cohort study of patients with chronic disabled work-related spinal disorder tested for the flexion-relaxation (FR) phenomenon while measured simultaneously for lumbar spine inclinometric range of motion (ROM). OBJECTIVES: To describe a theoretical model for the potential use of FR unloaded in assessing patients with chronic low back pain patients before and after rehabilitation, and to establish a normative database (Part 1) for subsequent use in comparison to patients with chronic low back pain (Part 2). The second part of the study assessed the clinical utility of combined sEMG and ROM measurements for assessing the FR phenomenon as a test to assist potentially in planning rehabilitation programs, guiding patients' individual rehabilitation progress, and identifying early posttreatment outcome failures. SUMMARY OF BACKGROUND DATA: The FR phenomenon has been recognized since 1951, and it can be reproducibly assessed in normal subjects with FR unloaded. It can be found intermittently in patients with chronic low back pain. Recent studies have moved toward deriving formulas to identify FR, but only a few have examined a potential relation between inclinometric lumbar motion measures and the sEMG signal. No previous studies have developed normative data potentially useful for objectively assessing nonoperative treatment progress, effort, or the validity of permanent impairment rating measures. METHODS: In Part 1, 12 asymptomatic subjects were evaluated in an intra- and interrater repeated-measures protocol to examine reliability of sEMG signal readings in FR, as well as ROM measures at FR and maximum voluntary flexion. The mean sEMG signal averaging right-left electrode recordings, as well as the gross, true, and sacral lumbar ROM measurements, were recorded as normative data. In Part 2, 54 patients with chronic disabled work-related spinal disorder referred as candidates for tertiary functional restoration rehabilitation participated in a standardized assessment protocol for sEMG and ROM measurement before rehabilitation. Those who completed the program were retested with the identical methodology after rehabilitation (n = 34) using the empirically derived cutoff scores for sEMG readings at FR and ROM from Part 1 and prior scientific literature. Pain disability self-reported scores were correlated with sEMG and ROM. Sensitivity and specificity of the sEMG for identifying abnormal motion were assessed. RESULTS: In Part 1, the ability of the experienced testers to measure ROM and sEMG reliably at FR was high (r >or= 0.92; P < 0.001). All asymptomatic subjects achieved FR at a tightly clustered range of mean sEMG signals from 1 to 2.3 microV. Most of the variation between motion at FR and maximum voluntary flexion occurred through the hip (sacral) motion component of the gross (or total) motion measured at T12. In Part 2, posttreatment reliability for ROM, sEMG, and the ability to detect the FR point was high (r >or= 0.82; P < 0.001). More than 30% of the 54 patients tested before treatment demonstrated ability to achieve FR, with FR usually associated with higher ROM than in the non-FR patients. After treatment, 94% of those who completed the program achieved FR, including all those who achieved FR before treatment. Flexion-relaxation was associated with major improvement in ROM and pain disability self-report. CONCLUSIONS: Flexion-relaxation measures a point at which true lumbar flexion ROM approaches its maximum in asymptomatic subjects. This also is the point at which lumbar extensor muscle contraction relaxes, allowing the lumbar spine to hang on its posterior ligaments. The gluteal and hamstring muscles then lower the flexed trunk even further by allowing the pelvis to rotate around the hips. This phenomenon was subsequently found in Part 2 to offer a potentially promising method for individualizing rehabilitation treatment, decreasing unnecessary utilization, identifying potential postrehabilitation treatment failures, and assessing permanent impairment rating validity. Moreover, this is the first study to demonstrate systematically that an absence of FR in patients with chronic low back pain can be corrected with treatment.

A prospective short-term study of chronic low back pain patients utilizing novel objective functional measurement.

The present study utilized recently developed diagnostic tests that permit recognition of functional deficits in spine mobility, trunk strength, endurance, coordination, and dynamic lifting capacity. Changes in these tests were compared to changes in psychological functioning (e.g., self-report of pain) as well as to outcome criteria such as return-to-work and resolution of litigation. The study utilized these tests repeatedly during a new treatment approach to feed back objective information of the patient's functional capacity, not amenable to simple visual inspection, to both the patient and the surgeon. The program itself integrated a low back physical rehabilitation program with a multimodal pain management program and was guided by repeated functional capacity measurements. A total of 66 patients were evaluated. Results demonstrated significant improvement in physical function in these patients, which was also accompanied by changes in self-report of pain complaints. Moreover, an 82% return-to-work rate was achieved in this sample which was initially 92% unemployed. These results indicate that the physician dealing with chronic low back dysfunction can employ objective measures of functional capacity as an alternative to the sole reliance on pain patient self-report or structured tests, such as radiographic imaging, which merely document a universal, progressive degenerative process.