Quantification of walking ability in subjects with neurogenic claudication from lumbar spinal stenosis--a comparative study.

BACKGROUND CONTEXT: Walking limitations caused by neurogenic claudication (NC) are typically assessed with self-reported measures, although objective evaluation of walking using motorized treadmill test (MTT) or self-paced walking test (SPWT) has periodically appeared in the lumbar spinal stenosis (LSS) literature. PURPOSE: This study compared the validity and responsiveness of MTT and SPWT for assessing walking ability before and after common treatments for NC. STUDY DESIGN: Prospective observational cohort study. PATIENT SAMPLE: Fifty adults were recruited from an urban spine center if they had LSS and substantial walking limitations from NC and were scheduled to undergo surgery (20%) or conservative treatment (80%). OUTCOME MEASURES: Walking times, distances, and speeds along with the characteristics of NC symptoms were recorded for MTT and SPWT. Self-reported measures included back and leg pain intensity assessed with 0 to 10 numeric pain scales, disability assessed with Oswestry Disability Index, walking ability assessed with estimated walking times and distances, and NC symptoms assessed with the subscales from the Spinal Stenosis Questionnaires. METHODS: Motorized treadmill test used a level track, and SPWT was conducted in a rectangular hallway. Walking speeds were self-selected, and test end points were NC, fatigue, or completion of the 30-minute test protocol. Results from MTT and SPWT were compared with each other and self-reported measures. Internal responsiveness was assessed by comparing changes in the initial results with the posttreatment results and external responsiveness by comparing walking test results that improved with those that did not improve by self-reported criteria. RESULTS: Mean age of the participants was 68 years, and 58% were male. Neurogenic claudication included leg pain (88%) and buttock(s) pain (12%). Five participants could not safely perform MTT. Walking speeds were faster and distances were greater with SPWT, although the results from both tests correlated with each other and self-reported measures. Of the participants, 72% reported improvement after treatment, which was confirmed by significant mean differences in self-reported measures. Motorized treadmill test results did not demonstrate internal responsiveness to change in clinical status after treatment but SPWT results did, with increased mean walking times (6 minutes) and distances (387 m). When responsiveness was assessed against external criterion, both SPWT and MTT demonstrated substantial divergence with self-reported changes in clinical status and alternative outcome measures. CONCLUSIONS: Both MTT and SPWT can quantify walking abilities in NC. As outcome tools, SPWT demonstrated better internal responsiveness than MTT, but neither test demonstrated adequate external responsiveness. Neither test should be considered as a meaningful substitution for disease-specific measures of function.

Acute low back pain is marked by variability: An internet-based pilot study.

BACKGROUND: Pain variability in acute LBP has received limited study. The objectives of this pilot study were to characterize fluctuations in pain during acute LBP, to determine whether self-reported 'flares' of pain represent discrete periods of increased pain intensity, and to examine whether the frequency of flares was associated with back-related disability outcomes. METHODS: We conducted a cohort study of acute LBP patients utilizing frequent serial assessments and Internet-based data collection. Adults with acute LBP (lasting ≤3 months) completed questionnaires at the time of seeking care, and at both 3-day and 1-week intervals, for 6 weeks. Back pain was measured using a numerical pain rating scale (NPRS), and disability was measured using the Oswestry Disability Index (ODI). A pain flare was defined as 'a period of increased pain lasting at least 2 hours, when your pain intensity is distinctly worse than it has been recently'. We used mixed-effects linear regression to model longitudinal changes in pain intensity, and multivariate linear regression to model associations between flare frequency and disability outcomes. RESULTS: 42 of 47 participants (89%) reported pain flares, and the average number of discrete flare periods per patient was 3.5 over 6 weeks of follow-up. More than half of flares were less than 4 hours in duration, and about 75% of flares were less than one day in duration. A model with a quadratic trend for time best characterized improvements in pain. Pain decreased rapidly during the first 14 days after seeking care, and leveled off after about 28 days. Patients who reported a pain flare experienced an almost 3-point greater current NPRS than those not reporting a flare (mean difference [SD] 2.70 [0.11]; p < 0.0001). Higher flare frequency was independently associated with a higher final ODI score (ß [SE} 0.28 (0.08); p = 0.002). CONCLUSIONS: Acute LBP is characterized by variability. Patients with acute LBP report multiple distinct flares of pain, which correspond to discrete increases in pain intensity. A higher flare frequency is associated with worse disability outcomes.

Nonsurgical treatment of lumbar disk herniation: are outcomes different in older adults?

OBJECTIVES: To determine whether older adults (aged ≥ 60) experience less improvement in disability and pain with nonsurgical treatment of lumbar disk herniation (LDH) than younger adults (< 60). DESIGN: Prospective longitudinal comparative cohort study. SETTING: Outpatient specialty spine clinic. PARTICIPANTS: One hundred thirty-three consecutive patients with radicular pain and magnetic resonance-confirmed acute LDH (89 younger, 44 older). INTERVENTION: Nonsurgical treatment customized for the individual patient. MEASUREMENTS: Patient-reported disability on the Oswestry Disability Index (ODI), leg pain intensity, and back pain intensity were recorded at baseline and 1, 3, and 6 months. The primary outcome was the ODI change score at 6 months. Secondary longitudinal analyses examined rates of change over the follow-up period. RESULTS: Older adults demonstrated improvements in ODI (range 0-100) and pain intensity (range 0-10) with nonsurgical treatment that were not significantly different from those seen in younger adults at 6 month follow-up, with or without adjustment for potential confounders. Adjusted mean improvement in older and younger adults were 31 versus 33 (P = .63) for ODI, 4.5 versus 4.5 (P = .99) for leg pain, and 2.4 versus 2.7 for back pain (P = .69). A greater amount of the total improvement in leg pain and back pain in older adults was noted in the first month of follow-up than in younger adults. CONCLUSION: These preliminary findings suggest that the outcomes of LDH with nonsurgical treatment were not worse in older adults (≥ 60) than in younger adults (< 60). Future research is warranted to examine nonsurgical treatment for LDH in older adults.

The accuracy of the physical examination for the diagnosis of midlumbar and low lumbar nerve root impingement.

STUDY DESIGN: Cross-sectional study with prospective recruitment. OBJECTIVE.: To determine the accuracy of the physical examination for the diagnosis of midlumbar nerve root impingement (L2, L3, or L4), low lumbar nerve root impingement (L5 or S1) and level-specific lumbar nerve root impingement on magnetic resonance imaging, using individual tests and combinations of tests. SUMMARY OF BACKGROUND DATA: The sensitivity and specificity of the physical examination for the localization of nerve root impingement has not been previously studied. METHODS: Sensitivities, specificities, and likelihood ratios (LRs) were calculated for the ability of individual tests and test combinations to predict the presence or absence of nerve root impingement at midlumbar, low lumbar, and specific nerve root levels. RESULTS: LRs ≥5.0 indicate moderate to large changes from pre-test probability of nerve root impingement to post-test probability. For the diagnosis of midlumbar impingement, the femoral stretch test (FST), crossed FST, medial ankle pinprick sensation, and patellar reflex testing demonstrated LRs ≥5.0 (LR ∞). LRs ≥5.0 were observed with the combinations of FST and either patellar reflex testing (LR 7.0; 95% confidence interval [CI] 2.3-21) or the sit-to-stand test (LR ∞). For the diagnosis of low lumbar impingement, the Achilles reflex test demonstrated an LR ≥5.0 (LR 7.1; 95% CI 0.96-53); test combinations did not increase LRs. For the diagnosis of level-specific impingement, LRs ≥5.0 were observed for anterior thigh sensation at L2 (LR 13; 95% CI 1.8-87); FST at L3 (LR 5.7; 95% CI 2.3-4.4); patellar reflex testing (LR 7.7; 95% CI 1.7-35), medial ankle sensation (LR ∞), or crossed FST (LR 13; 95% CI 1.8-87) at L4; and hip abductor strength at L5 (LR 11; 95% CI 1.3-84). Test combinations increased LRs for level-specific root impingement at the L4 level only. CONCLUSION: Individual physical examination tests may provide clinical information that substantially alters the likelihood that midlumbar impingement, low lumbar impingement, or level-specific impingement is present. Test combinations improve diagnostic accuracy for midlum-bar impingement.

Inciting events associated with lumbar disc herniation.

BACKGROUND CONTEXT: No prior study has investigated the frequency of patient-identified inciting events in lumbar disc herniation (LDH) or their clinical significance. PURPOSE: To examine the clinical frequency of patient-identified inciting events in LDH, and to identify associations between the presence of inciting events and the severity of the clinical presentation. STUDY DESIGN/SETTING: Cross-sectional analysis of data from a cohort study with prospective recruitment, with retrospective data collection on inciting events. The setting was a hospital-based specialty spine clinic. PATIENT SAMPLE: One hundred fifty-four adults with lumbosacral radicular pain and LDH confirmed by magnetic resonance imaging. OUTCOME MEASURES: Self-report measures of disability measured by the Oswestry Disability Index (ODI), the visual analog scale (VAS) for leg pain, and the VAS for back pain. METHODS: Dependent variables included the presence of a patient-identified inciting event, which were categorized as spontaneous onset, nonlifting physical activity, heavy lifting (>35 lbs), light lifting (<35 lbs), nonexertional occurrence, or physical trauma. We examined the association of an inciting event, or a lifting-related event, with each outcome, first using univariate analyses, and second using multivariate modeling, accounting for important adjustment variables. RESULTS: Sixty-two percent of LDH did not have a specific patient-identified event associated with onset of symptoms. Nonlifting activities were the most common inciting event, comprising 26% of all LDH. Heavy lifting (6.5%), light lifting (2%), nonexertional occurrences (2%), and physical trauma (1.3%) accounted for relatively small proportions of all LDH. Patient-identified inciting events were not significantly associated with a more severe clinical presentation in crude analyses. Spontaneous LDH was significantly associated with higher baseline ODI scores in multivariate analysis, although the magnitude of this effect was small. There were no significant associations (p< or =.05) between the presence of a lifting-associated event and the outcomes of ODI, VAS leg pain, or VAS back pain. CONCLUSIONS: The majority of LDH occurred without specific inciting events. A history of an inciting event was not significantly associated with a more severe clinical presentation. There was no significant association between the occurrence of a lifting-related event and the severity of the clinical presentation. This information may be useful in the counseling of patients recovering from acute LDH.

Assessment of forearm pronation strength in C6 and C7 radiculopathies.

STUDY DESIGN: Consecutive case series of patients with C6 and C7 radiculopathies. OBJECTIVES: To explore the clinical utility and reliability of manual muscle testing of forearm pronation strength in C6 and C7 radiculopathies. SUMMARY OF BACKGROUND DATA: EMG evidence of denervation of the pronator teres was the most common finding in C6 radiculopathies, and frequently present in C7 radiculopathies. Clinical evaluation of the pronator teres through manual muscle testing of forearm pronation has never been explored; therefore, its clinical utility is unknown as compared with the muscle groups that are traditionally evaluated. METHODS: Fifty-five subjects with diagnostic imaging evidence of either C6 (n = 25) or C7 (n = 30) cervical root compression and clinical symptoms consistent with cervical radiculopathy were recruited for this study. These subjects underwent manual muscle testing of forearm pronation, wrist extension, elbow flexion, and elbow extension. The frequency of impaired strength was recorded and compared for C6 and C7 radiculopathies. A second examiner evaluated each subject, with his or her findings compared with the first examiner only for the determination of interrater reliability. RESULTS: In C6 radiculopathy subjects, forearm pronation weakness was present in 72%, was twice as common as wrist extension weakness, was present in all cases where elbow flexion or wrist extension weakness was noted, and was found in all but 2 subjects where elbow extension weakness was present. In C7 radiculopathy subjects, forearm pronation weakness accompanies elbow extension weakness in 23% of subjects and was the only weakness in 10% of subjects. Manual muscle testing demonstrated adequate interrater reliability. CONCLUSIONS: Forearm pronation weakness is the most frequent motor finding in C6 radiculopathies and may be noted is some cases of C7 nerve root compression.

The influence of intense exercise-based physical therapy program on back pain anticipated before and induced by physical activities.

BACKGROUND CONTEXT: Pain anticipated before and induced by physical activities has been shown to influence the physical performance of patients with chronic back pain. Limited data exist as to the influence of treatment on this component of pain. PURPOSE: This study attempted to determine if pain anticipated before and induced by physical activities was altered during an exercise-oriented physical therapy program for chronic back pain. STUDY DESIGN/SETTING: Subjects were recruited from three physical therapy sites with similar spine rehabilitation programs that used intense exercise delivered in a group format. During the recruitment period, 70 subjects with chronic low back pain and disability agreed to participate and complied with recommended treatments. The primary outcome measures were anticipated and induced pain as assessed by visual analog scales (VAS) during six tests of back flexibility and strength. Additional outcome measures included the performance levels of these six tests (trunk flexion, extension, straight leg raising, back strength, lifting from floor to waist and waist to shoulder height), global back and leg VAS and Oswestry Low Back Pain Disability Questionnaire scores. METHODS: At evaluation for the spine rehabilitation programs, we recorded the anticipated and induced pain levels associated with the six tests of back function, the performance levels on each test and global pain and disability scores. Subjects then participated in the spine rehabilitation program that consisted of intense exercise delivered up to three times per week, for 2 hours over a period of 6 weeks. All outcome measures were reassessed at discharge. Pre- and posttreatment outcome scores were statistically compared using paired sample t tests and chi-squared test. Spearman correlation coefficients were used to compare anticipated and induced pain results with global back and leg pain VAS scores, Oswestry scores and physical performance levels for each physical test. RESULTS: Most measures of anticipated and induced pain improved between evaluation and discharge. Improvements were noted for global back pain (p<.001), leg pain (p=.001), disability (p<.001) and performance on each physical testing (p<.001) after treatment. Performances on all physical testing correlated with anticipated and induced pain for all tests at evaluation but only for measures of flexibility at discharge. Improvements in global pain and disability correlated with improvements in anticipated and induced pain with physical testing. CONCLUSION: Anticipated and induced pain with physical activities was lessened after physical therapy using exercise. Anticipated and induced pain with physical activities related to physical performance levels, global pain and disability ratings. These findings may help explain how exercise exerts a positive influence on chronic back pain and disability.

Exercise as a treatment for chronic low back pain.

BACKGROUND CONTEXT: Exercise is a widely prescribed treatment for chronic low back pain, with demonstrated effectiveness for improving function and work. PURPOSE: The goal of this article is to review several key aspects about the safety and efficacy of exercise that may help clinicians understand its utility in treating chronic back pain. STUDY DESIGN/SETTING: A computerized literature search of MEDLINE was conducted using "exercise," "fitness," "back pain," "backache" and "rehabilitation" as search words. Identified abstracts were scanned, and useful articles were acquired for further review. Additional references were acquired through the personal collections of research papers possessed by the authors and by reviewing prior review articles on this subject. These final papers were scrutinized for data relevant to the key aspects about exercise covered in this article. RESULTS: For people with acute, subacute or chronic low back pain, there is no evidence that exercise increases the risk of additional back problems or work disability. To the contrary, current medical literature suggests that exercise has either a neutral effect or may slightly reduce risk of future back injuries. Exercise can be prescribed for patients with chronic low back pain with three distinct goals. The first and most obvious goal is to improve or eliminate impairments in back flexibility and strength, and improve performance of endurance activities. There is a large body of evidence confirming that this goal can be accomplished for a majority of patients with chronic low back pain. The second goal of exercise is to reduce the intensity of back pain. Most studies of exercise have noted overall reduction in back pain intensity that ranges from 10% to 50% after exercise treatment. The third goal of exercise is to reduce back pain-related disability through a process of desensitization of fears and concerns, altering pain attitudes and beliefs and improving affect. The mechanisms through which exercise can accomplish this goal have been the subject of substantial research. CONCLUSIONS: Exercise is safe for individuals with back pain, because it does not increase the risk of future back injuries or work absence. Substantial evidence exists supporting the use of exercise as a therapeutic tool to improve impairments in back flexibility and strength. Most studies have observed improvements in global pain ratings after exercise programs, and many have observed that exercise can lessen the behavioral, cognitive, affect and disability aspects of back pain syndromes.

Comparison of four tests of quadriceps strength in L3 or L4 radiculopathies.

STUDY DESIGN: This prospective cohort study evaluated four office tests of quadriceps strength in symptomatic adults with radiographic evidence of L3 or L4 nerve root compression. OBJECTIVE: The study observed the performance of each test for its ability to detect quadriceps weakness when compared to the asymptomatic side. To determine the potential influence of radicular pain on the performance of the four tests, a control group of patients over the age of 40 with clinical and radiographic L5 or S1 radiculopathies underwent identical testing of quadriceps strength. SUMMARY OF BACKGROUND DATA: The L3 and L4 nerve roots innervate the quadriceps; therefore, quadriceps weakness may be a consequence of L3 or L4 radiculopathies. There are no standardized or validated methods to evaluate quadriceps strength in the clinical office setting. This may lead to inconsistent detection by clinicians of quadriceps weakness in cases of L3 or L4 radiculopathy. METHODS: Thirty-three consecutive patients with L3 or L4 radiculopathies and 19 with L5 or S1 radiculopathies were studied. The four tests of quadriceps strength included: 1) single leg sit-to-stand test; 2) step-up test; 3) knee-flexed manual muscle testing; and 4) knee-extended manual muscle testing. Results from a second examiner repeating the four tests were used to calculate interrater reliability. RESULTS: In L3 and L4 radiculopathies, unilateral quadriceps weakness was detected by the single leg sit-to-stand test in 61%, by knee-flexed manual muscle testing in 42%, by step-up test in 27% and by knee-extended manual muscle testing in 9% of patients. The sit-to-stand test detected weakness in all but one case when weakness was detected by another test. All patients with L5 or S1 radiculopathies could perform the sit-to-stand test. Kappa coefficient was high for sit-to-stand test (0.85), step-up (0.83), and knee-flexed manual muscle testing (0.66), and low for knee-extended manual muscle testing (0.08). CONCLUSION: In L3 and L4 radiculopathies, unilateral quadriceps weakness was best detected by a single leg sit-to-stand test. Patients of similar age with radicular pain caused by L5 or S1 radiculopathies could perform this test. As the interrater reliability of the single leg sit-to-stand test is high, clinicians should consider utilizing this test for assessing quadriceps strength in cases of L3 and L4 radiculopathies.

Comparison of short- and long-term outcomes for aggressive spine rehabilitation delivered two versus three times per week.

BACKGROUND CONTEXT: Rehabilitation services using intensive exercise for the treatment of chronic spinal pain have traditionally been scheduled at a frequency of three times per week. PURPOSE: In an attempt to reduce the cost of rehabilitation services, this study was designed to determine whether treatment offered two times per week could produce similar outcomes when compared with an established three times per week spine therapy program. STUDY DESIGN: Prospective cohort study. PATIENT SAMPLE: Seventy-seven consecutive patients with chronic spinal pain were treated with aggressive spine rehabilitation either two or three times per week. OUTCOME MEASURES: Flexibility, trunk strength and lifting capacity were quantified before and after treatment. Pain visual analog scores and Oswestry disability scores were measured before and after treatment, as well as 12 months after treatment. METHODS: A two times per week physical therapy program was developed to be identical in its treatment method to an established three times per week, group-oriented physical therapy program used for the treatment of chronic spinal pain. Patients with spinal pain who continued to work despite chronic pain complaints were allowed to choose between the two therapy programs based on availability of treatment slots and convenience. Treatment consisted of non-pain contingent quota-based exercises targeting identified physical impairments. Treatment sessions lasted for 2 hours and consisted of 30 minutes of stretching, 30 minutes of low-impact step aerobics class and 1 hour of exercise on strength and endurance equipment. Therapy occurred in groups consisting of a maximum of eight patients who were closely supervised by two therapists. Targeted treatment time was 6 weeks. At 12 months after treatment, subjects were surveyed by mailed questionnaires. RESULTS: Seventy-seven patients with chronic spinal pain with a mean duration of symptoms of 32 months underwent treatment. Twenty-four subjects opted for the twice per week and 53 opted for the three times per week treatment. Seventy-one percent of subjects responded to the 12-month follow-up questionnaire. Physical and self-reported measures improved with both treatment frequencies. There were no differences in outcomes between treatment frequencies for measured flexibility, trunk strength, lifting capacity, pain intensity scores or Oswestry scores at the completion of treatment. At 12-month follow-up, no differences were noted between treatment frequencies for pain scores, Oswestry scores, patients' perceptions of adequacy of treatment, posttreatment exercise compliance or use of other treatments for their spinal problem. Total therapy visits were less in the two than three times per week groups (12 vs 15 visits). CONCLUSION: Similar outcomes were obtained from aggressive spine rehabilitation occurring two versus three times per week in patients presenting with moderate levels of chronic spinal pain. Reduction in physical therapy services and therefore cost did not adversely affect clinical outcomes in the treatment of this patient population.