Classification of Geriatric Low Back Pain Based on Hip Characteristics With a 12-Month Longitudinal Exploration of Clinical Outcomes: Findings From Delaware Spine Studies.

OBJECTIVE: The purpose of this study is to identify geriatric chronic low back pain (LBP) subgroups based on the presence of potentially modifiable hip impairments, using Latent Variable Mixture Modeling (LVMM), and to examine the prospective relationship between these subgroups and key outcomes over time. METHODS: Baseline, 3-month, 6-month, and 12-month data were collected from a prospective cohort of 250 community-dwelling older adults with chronic LBP. Comprehensive hip (symptoms, strength, range of motion, and flexibility), LBP (intensity and disability), and mobility function (gait speed and 6-Minute Walk Test) examinations were performed at each timepoint. Baseline hip measures were included in LVMM; observed classes/subgroups were compared longitudinally on LBP and mobility function outcomes using mixed models. RESULTS: Regarding LVMM, a model with 3 classes/subgroup fit best. Broadly speaking, subgroups were differentiated best by hip strength and symptom presence: subgroup 1 = strong and nonsymptomatic, subgroup 2 = weak and nonsymptomatic, and subgroup 3 = weak and symptomatic (WS). Regarding longitudinal mixed models, all subgroups improved in most outcomes over time. Specifically, over 12 months, the nonsymptomatic subgroups had lower LBP intensity and disability levels compared with the WS subgroup, whereas the strong and nonsymptomatic subgroup had better mobility function than the 2 "weak" subgroups. CONCLUSION: These subgroup classifications may help in tailoring specific interventions in future trials. Special attention should be given to the WS subgroup given their consistently poor LBP and mobility function outcomes. IMPACT: Among older adults with chronic low back pain, there are 3 hip subgroups: "strong and nonsymptomatic," "weak and nonsymptomatic," and "weak and symptomatic." People in these subgroups demonstrate different outcomes and require different treatment; proper identification will result in tailored interventions designed to benefit individual patients. In particular, people in the WS subgroup deserve special attention, because their outcomes are consistently poorer than those in the other subgroups.

Chronic Exertional Compartment Syndrome: A Clinical Update.

Chronic exertional compartment syndrome is a debilitating condition primarily associated in highly active individuals with an estimated incidence of approximately 1 in 2000 persons/year. The etiology remains unclear to date. The differential diagnosis includes, but is not limited to stress fractures, medial tibial stress syndrome, and popliteal artery entrapment syndrome. Clinical signs and symptoms include pain in the involved compartment with exertion dissipating quickly after activity. Diagnostic tests include intramuscular compartment pressure testing, magnetic resonance imaging, near-infrared spectrometry as well as shear wave electrography. Treatments consist of nonsurgical, surgical, or the combination of the two. Gait retraining and the use of botulinum toxin appear most promising. Diagnostic lidocaine injections are emerging as a prognostic and mapping tool. Minimal invasive surgical options are being utilized allowing quicker return to activity and decreased morbidity. This article reviews the anatomy, clinical signs and symptoms, diagnostics, nonsurgical, and surgical treatments for chronic exertional compartment syndrome.

Use of trunk muscle training and neuromuscular electrical stimulation to reduce pain and disability in an older adult with chronic low back pain: A case report.

Among older adults, low back pain (LBP) is common, costly, and disabling. Trunk muscle training (TMT) and neuromuscular electrical stimulation (NMES) have both been found to be effective in reducing LBP, but studies among older adults have been limited. An 83-year-old female with left-sided chronic LBP participated in a randomized controlled trial consisting of supervised TMT and NMES to the paraspinal muscles two times per week for 12 weeks. She also participated in a home exercise program. At the end of the intervention, she reported reduced LBP and LBP-related disability per the modified Oswestry disability index (i.e., 60% at baseline to 40% at 12 weeks). Her Short Physical Performance Battery summary score improved from 4/12 at baseline to 10/12 at 12 weeks, while her Timed Up and Go test improved from 17.21 to 15.20 s and her Repetitive Trunk Rotation test from 2.72 to 1.93 s/right-left rotation. This case demonstrates a positive short-term treatment response to TMT supplemented with NMES of the paraspinal muscles in an older adult with chronic LBP. A packaged intervention of TMT plus NMES may be a means of addressing not only LBP, but also impaired physical function and resultant disability.

Hip Symptoms, Physical Performance, and Health Status in Older Adults With Chronic Low Back Pain: A Preliminary Investigation.

OBJECTIVES: To determine (1) whether there are differences in the prevalence of clinical hip symptoms between older adults with and without chronic low back pain (CLBP); and (2) whether coexisting hip symptoms are associated with worse physical performance and poorer health-related quality of life (HRQOL). DESIGN: Case-control study. SETTING: Individuals participated in a standardized evaluation in a clinical laboratory. PARTICIPANTS: Clinical hip symptoms, which are proposed predictors of radiographic hip osteoarthritis according to American College of Rheumatology guidelines, were evaluated in a volunteer sample of community-dwelling older adults with CLBP (n=54; aged 60-85y) and in age- and sex-matched healthy controls (n=54). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Physical performance was measured by the repeated chair rise test and stair-climbing test. HRQOL was measured by the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). RESULTS: Hip joint pain, morning stiffness, and pain with hip internal rotation were more common among older adults with CLBP (P<.05). Participants with CLBP and coexisting hip symptoms had worse physical performance than individuals without CLBP or hip symptoms (P<.0001). Additionally, the presence of coexisting hip symptoms was associated with worse HRQOL, particularly in the domains of social functioning, mental health, and role limitations attributable to emotional problems as measured by the SF-36 (P<.01). CONCLUSIONS: Given our limited understanding of CLBP among older adults, there is a definitive need to systematically explore coexisting pain conditions that may contribute to worse outcomes. Based on these data, future longitudinal studies should explore whether coexisting hip symptoms are associated with a worse prognosis in older adults with CLBP.

Multifidi Muscle Characteristics and Physical Function Among Older Adults With and Without Chronic Low Back Pain.

OBJECTIVE: To determine whether multifidi size, intramuscular fat, or both, are associated with self-reported and performance-based physical function in older adults with and without chronic low back pain (LBP). DESIGN: Case-control study. SETTING: Individuals participated in a standardized evaluation in a clinical laboratory and underwent magnetic resonance imaging (MRI) of the lumbar spine at a nearby facility. PARTICIPANTS: A volunteer sample of community-dwelling older adults (N=106), aged 60 to 85 years, with (n=57) and without (n=49) chronic LBP were included in this secondary data analysis. INTERVENTION: Average right-left L5 multifidi relative (ie, total) cross-sectional area (CSA), muscle-fat infiltration index (MFI) (ie, a measure of intramuscular fat), and relative muscle CSA (rmCSA) (ie, total CSA minus intramuscular fat CSA) were determined from MRIs. Linear regression modeling was performed with physical function measures as the dependent variables. Age, sex, and body mass index were entered as covariates. The main effects of L5 multifidi MFI and rmCSA, as well as their interaction with group assignment, were compared as independent variables. MAIN OUTCOME MEASURES: Medical Outcomes Study 36-Item Short-Form Health Survey physical functioning subscale, timed Up and Go, gait speed, and fast stair descent performance. RESULTS: Interaction terms between L5 multifidi MFI and group assignment were found to be significant contributors to the variance explained in all physical function measures (P≤.012). Neither the main effect nor the interaction with group assignment for L5 multifidi rmCSA significantly contributed to the variance explained in any of the physical function measures (P>.012). CONCLUSIONS: Among older adults with chronic LBP of at least moderate intensity, L5 multifidi muscle composition, but not size, may help to explain physical function.

Trunk Muscle Training Augmented With Neuromuscular Electrical Stimulation Appears to Improve Function in Older Adults With Chronic Low Back Pain: A Randomized Preliminary Trial.

OBJECTIVES: To assess the feasibility of a trial to evaluate a trunk muscle training program augmented with neuromuscular electrical stimulation (TMT+NMES) for the rehabilitation of older adults with chronic low back pain (LBP) and to preliminarily investigate whether TMT+NMES could improve physical function and pain compared with a passive control intervention. MATERIALS AND METHODS: We conducted a single-blind, randomized feasibility trial. Patients aged 60 to 85 years were allocated to TMT+NMES (n=31) or a passive control intervention (n=33), consisting of passive treatments, that is, heat, ultrasound, and massage. Outcomes assessed 3- and 6-month postrandomization included Timed Up and Go Test, gait speed, pain, and LBP-related functional limitation. RESULTS: Feasibility was established by acceptable adherence (≥80%) and attrition (<20%) rates for both interventions. Both groups had similar, clinically important reductions in pain of >2 points on a numeric pain rating scale during the course of the trial. But, only the TMT+NMES group had clinically important improvements in both performance-based and self-reported measures of function. In terms of the participants' global rating of functional improvement at 6 months, the TMT+NMES group improved by 73.9% and the passive control group improved by 56.7% compared with baseline. The between-group difference was 17.2% (95% confidence interval, 5.87-28.60) in favor of TMT+NMES. DISCUSSION: It seems that a larger randomized trial investigating the efficacy of TMT+NMES for the purpose of improving physical function in older adults with chronic LBP is warranted.

Reliability of ultrasound imaging for the assessment of lumbar multifidi thickness in older adults with chronic low back pain.

BACKGROUND AND PURPOSE: Ultrasound imaging (USI) has been shown to be a reliable measure for direct assessment of the lumbar multifidi among younger adults. However, given age- and chronic low back pain (CLBP)-related spinal changes, similar studies are needed before clinical use of USI among older adults with CLBP. The goals of this study were to evaluate intra- and interexaminer reliability for USI assessment of multifidi thickness at rest and during a contraction and to determine standard error of measurement values (SEMs) and minimal detectable change values (MDCs) among older adults with CLBP. METHODS: Thirty-one adults, aged 60 to 85 years, with CLBP were recruited. Two examiners performed USI assessments of multifidus thickness at rest and during a contralateral lower extremity lift. Intraclass correlation coefficients (ICCs) were used to estimate inter- and intraexaminer reliability. Additionally, SEMs and MDCs were calculated. RESULTS: All USI measurement techniques demonstrated excellent within-day, interexaminer procedural reliability (ICCs: 0.82-0.85) and good-to-excellent between-day, interexaminer procedural reliability (ICCs: 0.72-0.79). The SEMs ranged from 0.36 to 0.46 cm; MDCs ranged from 1.01 to 1.26 cm. Regardless of the measurement technique, examiner 1, the more experienced examiner, demonstrated lower SEMs and MDCs than examiner 2. DISCUSSION: Lower ICCs, greater SEMs, and greater MDCs for USI multifidus thickness assessment in older adults with CLBP, when compared with previously published, procedural reliability results for younger adults with and without low back pain, may indicate that imaging is more challenging in this patient population. Factors, such as examiner training and participant anthropometrics, may impact reliability. CONCLUSIONS: Good-to-excellent intra- and interexaminer USI procedural reliability may provide clinicians a direct assessment technique for clinical evaluation of the lumbar multifidi in older adults with CLBP. SEMs and MDCs may allow for accurate interpretation of USI assessments in this population.

Ultrasound imaging: intraexaminer and interexaminer reliability for multifidus muscle thickness assessment in adults aged 60 to 85 years versus younger adults.

STUDY DESIGN: Intraexaminer and interexaminer, within- and between-day reliability study. OBJECTIVES: To compare the intraexaminer and interexaminer procedural reliability of ultrasound imaging (USI) thickness measurements of the lumbar multifidus muscle at rest and during a contralateral lower-limb lift (CLL) between older (60-85 years of age) and younger (18-40 years of age) adults. BACKGROUND: Among younger adults, USI has been shown to be reliable and valid for assessing multifidus thickness. Older adults present with age-related changes that may impact assessment. To our knowledge, no USI studies have focused on establishing reliability for multifidus thickness assessments in older adults. METHODS: Two examiners performed assessments of lumbar multifidus thickness at rest and during a CLL in 30 older and 31 younger adults. Intraclass correlation coefficient (ICC) with 95% confidence interval, standard error of measurement, 95% minimal detectable change for resting and during the CLL, and percent thickness change were calculated. RESULTS: Within-day interexaminer procedural reliability for multifidus thickness measurements was similar among younger (ICC = 0.90-0.92) and older adults (ICC = 0.86-0.90), as was between-day intraexaminer and interexaminer reliability (younger adults, ICC = 0.84-0.94; older adults, ICC = 0.86-0.93). Throughout, estimates of percent thickness change were inconsistent (ICC = 0.31-0.86), and standard errors of measurement and minimal detectable changes were larger for older adults. CONCLUSION: Ultrasound imaging reliability for measurements of multifidus thickness at rest and during a CLL among older adults is consistent with previously published findings for younger adults. Among older adults, it may be preferable to have a single examiner conduct USI assessments.