The effects of lumbo-pelvic postural taping on gait parameters in patients with lumbar spinal stenosis

BackgroundAltered gait patterns with lumbar-flexed posture threaten the quality of life in patients with lumbar spinal stenosis; however, few studies have developed management strategies to improve gait patterns and lumbo-pelvic posture. The present study investigated the effects of lumbo-pelvic postural taping on pelvic tilt, spatiotemporal gait parameters, and pain during walking in patients with lumbar spinal stenosis.MethodsThe pelvic tilt and gait parameters were assessed in 20 patients with lumbar spinal stenosis before sustained walking using a palpation meter and GAITRite system, respectively. Next, the participants were asked to walk on the ground for 20 min or until they complained of symptoms of neurogenic claudication. Pelvic tilt and gait parameters were measured immediately after the manifestation of neurogenic claudication followed by the application of lumbo-pelvic postural taping. The participants rated the pain intensity using a visual analog scale. Changes in dependent variables among the conditions were analyzed using a one-way repeated-measures analysis of variance.FindingsThe results show a decreased pelvic anterior tilt, walking velocity, and step and stride lengths, as well as an increased base of support and pain after severe symptoms of neurogenic claudication (P < 0.05). However, a greater pelvic anterior tilt, faster walking velocity with a longer step and stride length, and decreased base of support and pain were found after the application of postural taping (P ≤ 0.001).InterpretationThese findings suggest that lumbo-pelvic postural taping can provide beneficial management for improving gait patterns and lumbo-pelvic posture in patients with lumbar spinal stenosis.     

Characteristics of thoracic and lumbar movements during gait in lumbar spinal stenosis patients before and after decompression surgery

BackgroundAlthough gait analysis has been previously conducted for lumbar spinal stenosis patients, the vertebral segmental movements, such as of the thoracic and lumbar regions, and whether the spinal movement during gait changes after decompression surgery remain unclear.MethodsTen patients with lumbar spinal stenosis and 10 healthy controls participated. Clinical outcomes were assessed using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire and Visual Analogue Scale. Spinal kinematic data of the participants during gait were acquired using a three-dimensional motion analysis system. The trunk (whole spine), thoracic, and lumbar flexion and pelvic tilting values were calculated. Spinal kinematic data and clinical outcomes were collected preoperatively and 1 month postoperatively for the patients.FindingsCompared to that observed preoperatively, the clinical outcomes significantly improved at 1 month postoperatively. In the standing position, the preoperative lumbar extension of the patients was significantly smaller than that of the controls. Moreover, during gait, the lumbar flexion relative to the standing position of the patients was smaller than that of the controls preoperatively, and increased at 1 month postoperatively. The sum of the thoracic and lumbar flexion values during gait negatively correlated with the score for leg pain.InterpretationThe epidural pressure of lumbar spinal stenosis patients is known to be higher than that of normal subjects during gait, and to decrease during walking with lumbar flexion. Preoperatively, smaller thoracic and lumbar flexion movements during gait relative to the standing position cannot decrease epidural pressure; as a result, severe leg pain might be induced.     

Lesser lower extremity mechanical loading associates with a greater increase in serum cartilage oligomeric matrix protein following walking in individuals with anterior cruciate ligament reconstruction

BackgroundAberrant mechanical loading during gait is hypothesized to contribute to the development of posttraumatic osteoarthritis following anterior cruciate ligament reconstruction. Our purpose was to determine if peak vertical ground reaction force and instantaneous vertical ground reaction force loading rate associate with the acute change in serum cartilage oligomeric matrix protein following a 20-minute bout of walking.MethodsWe enrolled thirty individuals with a unilateral anterior cruciate ligament reconstruction. Peak vertical ground reaction force and instantaneous vertical ground reaction force loading rate were extracted from the first 50% of the stance phase of gait during a 60-second trial. Blood samples were collected immediately before and after 20 min of treadmill walking at self-selected speed. The change in serum cartilage oligomeric matrix protein from pre- to post-walking was calculated. Stepwise linear regression models were used to determine the association between each outcome of loading and the change in serum cartilage oligomeric matrix protein after accounting for sex, gait speed, time since anterior cruciate ligament reconstruction, graft type, and history of concomitant meniscal procedure (ΔR²).FindingsLesser peak vertical ground reaction force (ΔR² = 0.208; β = −0.561; P = 0.019) and instantaneous vertical ground reaction force loading rate (ΔR² = 0.168; β = −0.519; P = 0.037) on the anterior cruciate ligament reconstructed limb associated with a greater increase in serum cartilage oligomeric matrix protein following 20 min of walking.InterpretationMechanical loading may be a future therapeutic target for altering the acute biochemical response to walking in individuals with an anterior cruciate ligament reconstruction.     

Immediate Effects of Single-Session Proprioceptive Neuromuscular Facilitation Exercises on the Sit-to-Stand Strategy in Patients With Chronic Lumbar Spinal Disc Disease: A Preliminary Study

ObjectiveThe purpose of this study was to measure the immediate effects of single-session proprioceptive neuromuscular facilitation exercises on the sit-to-stand (STS) task and level of pain in patients with chronic low back pain.MethodsFifty-three patients were assigned to the control and intervention groups. The total time was 30 minutes (each exercise 5 minutes). The minimum vertical ground reaction force (VGRF_min) and maximum vertical ground reaction force (VGRF_max) and time phases (T_min – time to counterforce, T_max – time to peak force, T_tot – time to post-peak rebound force) were measured with a Kistler force plate in eyes-open and eyes-closed conditions during the STS task. Pain level was determined on a numeric rating scale.ResultsMain effects were observed only in the intervention group: decreasing pain value (F = 25.398, P < .0001), increasing T_min (F = 5.72, P = .0044), decreasing T_max (F = 3.43, P = .04), and decreasing T_tot (F = 3.935, P = .02258). There was a main effect of the eyes factor on VGRF_min (F = 12.53, P < .0001) and VGRF_max (F = 7.16, P < .01).ConclusionImmediate effects of single-session proprioceptive neuromuscular facilitation exercises were observed in decreasing the level of pain. Adaptation effects were noted in the retention test. The STS task could be optimized in time phases and dynamic movements in patients with chronic low back pain.     

Effects of intermittent claudication due to arterial disease on pain-free gait

IntroductionStudies of intermittent claudication gait report inconsistent outcomes. Changes in gait are often attributed to degradation of calf muscles, but causation has not been proven through real-time electromyographic data. Neither have effects of walking speed been fully considered. This study aimed to investigate the effect of intermittent claudication on kinematics, kinetics and muscle activity during pain-free gait.Methods18 able bodied individuals and 18 with intermittent claudication walked at their preferred speed while lower limb kinematic, kinetic and electromyography data were collected.FindingsPeople with intermittent claudication walk slower and with reduced step length. Internal ankle plantarflexion moment (P = 0.004, effect size = 0.96) and ankle power generation (P < 0.001, effect size = 1.36) in late stance were significantly reduced for individuals with intermittent claudication. Significant moment and power reductions at the knee and power reduction at hip occurred in early stance, with similar reductions in early and late stance for ground reaction forces. Peak electromyography of soleus activity was significantly reduced in late stance (P = 0.01, effect size = 1.1, n = 13). Effects were independent of walking speed.InterpretationReductions in ankle plantarflexion moments and power generation were consistent with reduced soleus electromyography activity and reduced peak vertical ground reaction forces during late stance. These effects are not due to a reduced walking speed. Changes in knee and hip function are also unrelated to walking speed. These outcomes provide a platform for the design and evaluation of interventions that seek to restore normal walking and improve pain-free walking distances for people with intermittent claudication.     

A comparison of ground reaction force waveforms and step length between recreational endurance runners with hamstring injuries and healthy controls

BackgroundAcute hamstring injuries during sprinting have been attributed, in part, to the ground reaction forces experienced during early stance. However, no studies have investigated the factors associated with overuse hamstring injuries in endurance runners. Our purpose was to compare early stance ground reaction forces and step length between runners with overuse hamstring injuries and healthy controls.Methods23 runners (5 men/ 18 women) who presented to a running clinic with an overuse hamstring injury were matched with healthy controls for sex, running speed and age. All participants ran on an instrumented treadmill, embedded with force plates. A 3-min warm-up was given, at a self-selected training pace, followed by 16-s of ground reaction force data collection (≈20 strides). Statistical parametric mapping was used to compared ground reaction force waveforms. Additionally, discrete force variables were calculated, including vertical average/instantaneous. Mean comparisons for discrete ground reaction force variables and step length were performed.FindingsDifferences in ground reaction force waveforms did not reach statistical significance (p > 0.05). However, mean vertical loading rates were found to be higher in the Hamstring Injury group compared to Controls (p = 0.03–0.04) with small to moderate effect sizes (d = 0.47–0.52). No differences were found in mean step length.InterpretationThese results provide evidence that vertical loading rates may be associated with overuse hamstring injuries. However, further research is needed to identify the contribution of joint kinematics/kinetics and muscle activity.     

In vivo relationships between lumbar facet joint and intervertebral disc composition and diurnal deformation

BackgroundSpinal motion is facilitated by a “three joint complex”, two facet joints and one intervertebral disc at each spinal level. Both the intervertebral discs and facet joints are subject to natural age-related degeneration, and while these processes may be linked it is not clear how. As instability in the disc could underlie facet arthritis, we evaluated the hypothesis that the discs and facet joints are mechanically coupled.MethodsWe recruited young, asymptomatic volunteers (n = 10; age: mean 25, range 21–30 years; BMI: mean 23.1, range 19.1–29.0 kg/m²) and applied magnetic resonance imaging (MRI) and three-dimensional (3D) modeling to measure facet and disc composition (MRI T1rho relaxation time) and facet and disc function (diurnal changes in facet space width, disc height) in the lumbar spine.FindingsWe found that facet space width was positively associated with facet T1rho relaxation time (fluid content) and negatively associated with disc T1rho, and that facets adjacent to degenerated discs were significantly thicker and had significantly higher T1rho. Furthermore, the diurnal change in wedge angle was positively associated the diurnal change in facet space width, while disc degeneration, the diurnal change in disc height, and facet T1rho were not.InterpretationThese data demonstrate an interdependence between disc and facet health, but not between disc and facet mechanical function. Furthermore, the weak relationship between facet cartilage composition and in vivo function suggests that other factors, like spinal curvature, determine in vivo spine mechanics. Future work in symptomatic or aged populations are warranted to confirm these findings.     

Impact loading following quadriceps strength training in individuals with medial knee osteoarthritis and varus alignment

BackgroundGreater impact loading at initial contact is postulated to play a role in the progression of osteoarthritis. Quadriceps weakness is common in individuals with knee osteoarthritis and may contribute to high impact loading. The purpose of this study was to examine the effects of quadriceps strengthening on impact loading parameters.MethodsData from 97 individuals with knee osteoarthritis who participated in a randomized clinical trial examining effects of a 12-week quadriceps strengthening program was used to conduct this secondary exploratory analysis. Participants completed a three-dimensional gait assessment within 10% of 1.0 m/s from which maximum rate of loading (Body Weight/second), average rate of loading (Body Weight/second), and peak vertical ground reaction force during early stance (Body Weight) were determined. Peak isometric quadriceps strength (Nm/kg) was also assessed.FindingsThere was a significant increase in quadriceps strength in the training group (mean change (95%CI): 0.35(0.25, 0.045) Nm/kg, P = 0.01) with no change in the control group (mean change (95%CI): 0.03(− 0.39, 0.45) Nm/kg, P > 0.05). There were no changes in impact loading variables. With data from both groups combined, changes in quadriceps strength explained 3% of variance in the change in maximum rate of loading. Change in quadriceps strength was not predictive of the change in peak vertical ground reaction force or average rate of loading.InterpretationsWhile change in strength was predictive of change in maximal loading rate, this explained only a small proportion of the variance. Future research examining the role parameters such as neuromuscular control play in impact loading are warranted.     

Lower-extremity dynamics of walking in neuropathic diabetic patients who wear a forefoot-offloading shoe

BackgroundA forefoot-offloading shoes has a negative-heel rocker outsole and is used to treat diabetic plantar forefoot ulcers, but its mechanisms of action and their association with offloading and gait stability are not sufficiently clear.MethodsTen neuropathic diabetic patients were tested in a forefoot-offloading shoe and subsequently in a control shoe with no specific offloading construction, both worn on the right foot (control shoe on left), while walking at 1.2 m/s. 3D-instrumented gait analysis and simultaneous in-shoe plantar pressure measurements were used to explain the shoe's offloading efficacy and to define centre-of-pressure profiles and left-to-right symmetry in ankle joint dynamics (0–1, 1:maximum symmetry), as indicators for gait stability.FindingsCompared to the control shoe, peak forefoot pressures, vertical ground reaction force, plantar flexion angle, and ankle joint moment, all in terminal stance, and the proximal-to-distal centre-of-pressure trajectory were significantly reduced in the forefoot-offloading shoe (P < 0.01). Peak ankle joint power was 51% lower in the forefoot-offloading shoe compared to the control shoe: 1.61 (0.35) versus 3.30 (0.84) W/kg (mean (SD), P < 0.001), and was significantly associated with forefoot peak pressure (R² = 0.72, P < 0.001). Left-to-right symmetry in the forefoot-offloading shoe was 0.39 for peak ankle joint power.InterpretationBy virtue to their negative-heel rocker-outsole design, forefoot-offloading shoes significantly alter a neuropathic diabetic patient's gait towards a reduced push-off power that explains the shoe's offloading efficacy. However, gait symmetry and stability are compromised, and may be factors in the low perceived walking discomfort and limited use of these shoes in clinical practice. Shoe modifications (e.g. less negative heel, a more cushioning insole) may resolve this trade-off between efficacy and usability.     

Biomechanical effects of manipulating peak vertical ground reaction force throughout gait in individuals 6–12 months after anterior cruciate ligament reconstruction

BackgroundWe aimed to determine the effect of cueing an increase or decrease in the vertical ground reaction force impact peak (peak in the first 50% of stance) on vertical ground reaction force, knee flexion angle, internal knee extension moment, and internal knee abduction moment waveforms throughout stance in individuals 6–12 months after an anterior cruciate ligament reconstruction.MethodsTwelve individuals completed 3 conditions (High, Low, and Control) where High and Low Conditions cue a 5% body weight increase or decrease, respectively, in the vertical ground reaction force impact peak compared to usual walking. Biomechanics during High and Low Conditions were compared to the Control Condition throughout stance.FindingsThe High Condition resulted in: (a) increased vertical ground reaction forces at each peak and decreased during mid-stance, (b) greater knee excursion (i.e., greater knee flexion angle in early stance and a more extended knee in late stance), (c) greater internal extension moment for the majority of stance, and (d) lesser second internal knee abduction moment peak. The Low Condition resulted in: (a) vertical ground reaction forces decreased during early stance and increased during mid-stance, (b) decreased knee excursion, (c) increased internal extension moment throughout stance, and (d) decreased internal knee abduction moment peaks.InterpretationCueing a 5% body weight increase in vertical ground reaction force impact peak resulted in a more dynamic vertical ground reaction force loading pattern, increased knee excursion, and a greater internal extension moment during stance which may be useful in restoring gait patterns following anterior cruciate ligament reconstruction.     

Bilateral multidirectional jumps with reactive jump-landings achieve osteogenic thresholds with and without instruction in premenopausal women

BackgroundCurrently jump-landing ground reaction forces have only been quantified in the vertical direction as a stimulus for bone development. This study quantified the full-spectrum of jump-landing force magnitudes (body weight's) and rates of strain (body weights per second) of bilateral multidirectional jumps (star jump and stride jump) with reactive jump-landings (i.e. jumping immediately after initial jump-landing) among premenopausal women. It was also of interest to quantify the influence of instruction on the magnitude and rate of the jump-landing ground reaction forces.MethodsTwenty-one women [Mean (SD): 43.3(5.9)yr; 69.4(9.6)kg; 167(5.5)cm; 27.5(8.7)% body fat] performed a jump testing session ‘with instruction’ followed by a jump testing session performed one week later with ‘instruction withdrawn’.FindingsThe resultant magnitudes (3.90 to 5.38, body weights) and rates of strain (192 to 329, body weights per second) for the jump-landings, performed on a force plate, exceeded previously determined osteogenic thresholds (>3body weight's and >43body weights per second, respectively). An instruction effect was observed for resultant (↑8% and ↑12%; P ≤ .01) and vertical (↑8% and ↑7%; P ≤ .01) ground reaction force's (Newtons and body weight, respectively) indicating learning/practice effects for these exercises. A jump-landing effect was observed, with larger peak rates of strain (↑29%; P < .0001, body weight per second) and peak forces (↑12% to ↑48%; P ≤ .01, body weights) for the second jump-landing (post-reactive jump).InterpretationThese multidirectional bilateral jumps represent a unique training stimulus for premenopausal women and achieve osteogenic thresholds thought pre-requisite for bone growth and could be utilized in the development of osteogenic exercise programs.     

The effect of total hip and hip resurfacing arthroplasty on vertical ground reaction force and impulse symmetry during a sit-to-stand task

BackgroundThe aim of this study was to determine the influence of total hip arthroplasty and hip resurfacing arthroplasty on limb loading symmetry before, and after, hip reconstruction surgery during a sit-to-stand task.MethodsFourteen patients were recruited that were about to receive either a total hip prosthesis (n = 7) or a hip resurfacing prosthesis (n = 7), as well as matched controls. Patients performed a sit-to-stand movement before, 3 months after, and 12 months after surgery. Peak vertical ground reaction force and impulse were measured for each leg, from which ground reaction force and impulse symmetry ratios were calculated.FindingsBefore surgery, hip resurfacing patients showed a small asymmetry which was not different to normal for ground reaction force (0.88(0.28) vs. 1.00(0.11); p = 0.311) or impulse (0.87(0.29) vs. 0.99(0.09); p = 0.324) symmetry ratios. Total hip patients offloaded their affected hip by 30% in terms of impulse symmetry ratio (0.71(0.36) vs. 0.99(0.23); p = 0.018). At 3 months following surgery asymmetries were seen that were different to normal in both hip resurfacing patients for ground reaction force (0.77(0.16); p = 0.007), and total hip patients for ground reaction force (0.70(0.15); p = 0.018) and impulse (0.72(0.16); p = 0.011) symmetry ratios. By 12 months after surgery total hip patients regained a symmetrical loading pattern for both ground reaction force (0.95(0.06); p = 0.676) and impulse (1.00(0.06); p = 0.702) symmetry ratios. Hip resurfacing patients, however, performed the task by overloading their operated hip, with impulse symmetry ratio being larger than normal (1.16(0.16); p = 0.035).InterpretationPhysiotherapists should appreciate the need for early recovery of limb loading symmetry as well as subsequent differences in the responses observed with different prostheses.     

Gluteus medius dysfunction in females with chronic ankle instability is consistent at different walking speeds

BackgroundPatients with chronic ankle instability often present with altered gait mechanics compared to ankle sprain copers. There is increasing evidence to suggest proximal neuromuscular alterations contribute to the injury etiology, however little is known about how these changes manifest during gait. The purpose of this study was to investigate ipsilateral gluteus maximus and medius functional activity ratios throughout treadmill walking at three speeds (preferred, 120% preferred, and 1.35 m per second) in chronic ankle instability patients compared to copers.Methods28 females (14 chronic ankle instability, 14 copers) walked at the three gait speeds in randomized order. Ground reaction forces and 10-s gluteal ultrasound clips were simultaneously recorded. Clips were reduced using ground reaction forces to extract 55 measurement frames. Normalized gluteal thickness measures were used to determine functional activity ratios. 2 × 3 analyses of variance were run to assess group and speed effects on gluteal outcomes throughout walking using statistical parametric mapping. Post-hoc t-tests, mean differences, and Cohen's d effect sizes were assessed for significant findings (P ≤ .05).FindingsThe chronic ankle instability group had significantly decreased gluteus medius activity throughout the entire gait cycle when compared to the coper group, independent of gait speed (P < .001, mean differences: 0.10–0.18; d: 1.00–3.17). There were no significant group or speed main effects, nor an interaction for gluteus maximus activity.InterpretationGluteal dysfunction throughout walking was identified in chronic ankle instability. The coper group remained within healthy reference muscle activity ranges, suggesting that proximal muscle activation alterations are associated chronic ankle impairments.     

Multiple sclerosis affects the frequency content in the vertical ground reaction forces during walking

Background

Multiple sclerosis is a progressive neurological disease that results in a high incident of gait disturbance. Exploring the frequency content of the ground reaction forces generated during walking may provide additional insights to gait in patients with multiple sclerosis that could lead to specific tools for differential diagnosis. The purpose of this study was to investigate differences in the frequency content of these forces in an effort to contribute to improved clinical management of this disease.

Methods

Eighteen patients and eighteen healthy controls walked across a 10 meter long walkway. The anterior–posterior and vertical ground reaction forces generated during the stance phase of gait were evaluated in the frequency domain using fast Fourier transformation. T-tests were utilized for comparison of median frequency, the 99.5% frequency, and the frequency bandwidth between patients and healthy controls and also for comparisons between patients with mild and moderate severity.

Findings

Patients with multiple sclerosis had significantly lower 99.5% frequency (P = 0.006) and median frequency (P < 0.001) in the vertical ground reaction force. No differences were found in the anterior–posterior reaction force frequency content. There were no differences between patients with mild and moderate severity.

Interpretation

The lower frequency content suggests lesser vertical oscillation of the center of gravity. Lack of differences between severities may suggest presence of differences prior to currently established diagnosis timelines. Analysis of the frequency content may potentially serve to provide earlier diagnostic assessment of this debilitating disease.     

Lumbar extensor muscle force control is associated with disability in people with chronic low back pain

BackgroundThe ability to control lumbar extensor force output is necessary for daily activities. However, it is unknown whether this ability is impaired in chronic low back pain patients. Similarly, it is unknown whether lumbar extensor force control is related to the disability levels of chronic low back pain patients.MethodsThirty-three chronic low back pain and 20 healthy people performed lumbar extension force-matching task where they increased and decreased their force output to match a variable target force within 20%–50% maximal voluntary isometric contraction. Force control was quantified as the root-mean-square-error between participants' force output and target force across the entire, during the increasing and decreasing portions of the force curve. Within- and between-group differences in force-matching error and the relationship between back pain group's force-matching results and their Oswestry Disability Index scores were assessed using ANCOVA and linear regression respectively.FindingsBack pain group demonstrated more overall force-matching error (mean difference = 1.60 [0.78, 2.43], P < 0.01) and more force-matching error while increasing force output (mean difference = 2.19 [1.01, 3.37], P < 0.01) than control group. The back pain group demonstrated more force-matching error while increasing than decreasing force output (mean difference = 1.74, P < 0.001, 95%CI [0.87, 2.61]). A unit increase in force-matching error while decreasing force output is associated with a 47% increase in Oswestry score in back pain group (R² = 0.19, P = 0.006).InterpretationLumbar extensor muscle force control is compromised in chronic low back pain patients. Force-matching error predicts disability, confirming the validity of our force control protocol for chronic low back pain patients.     

Lead limb loading during a single-step descent in persons with and without a transtibial amputation in the trailing limb

BackgroundDecreased mechanical work done by the trailing limb when descending a single-step could affect load development and increase injury risk on the leading limb. This study assessed the effect of trailing limb mechanics on the development of lead limb load during a step descent by examining individuals with unilateral transtibial amputations who are known to exhibit reduced work in the prosthetic limb.MethodsEight amputees and 10 able-bodied controls walked 5 m along the length of a raised platform, descended a single-step of 14 cm height, and continued walking. The intact limb of amputees led during descent. Kinematic and kinetic data were recorded using integrated motion capture and force platform system. Lead limb loading was assessed through vertical ground reaction force, and knee moments and joint reaction forces. Sagittal-plane joint work was calculated for the ankle, knee, and hip in both limbs.FindingsNo differences were found in lead limb loading despite differences in trail limb mechanics evidenced by amputees performing 58% less total work by the trailing (prosthetic) limb to lower the centre of mass (P = 0.004) and 111% less for propulsion (P < 0.001). Amputees descended the step significantly slower (P = 0.003) and performed significantly greater lead limb ankle work (P = 0.017). After accounting for speed differences, initial loading at the knee was significantly higher in the lead limb of amputees versus controls.InterpretationIncreasing lead limb work and reducing forward velocity may be effective compensatory strategies to limit lead limb loading during a step descent, in response to reduced trailing limb work.     

Predictors of Long-Term Opioid Use Among Patients With Painful Lumbar Spine Conditions

Our objective was to assess predictors of self-reported opioid use among patients with back pain due to lumbar disc herniation or spinal stenosis. Data were from the Spine Patient Outcomes Research Trial (SPORT), a multi-site observational study and randomized trial. We examined characteristics shown or hypothesized to be associated with opioid use. Using generalized estimating equations, we modeled associations of each potential predictor with opioid use at 12 and 24 months. At baseline, 42% of participants reported opioid use. Of these participants, 25% reported continued use at 12 months and 21% reported use at 24 months. In adjusted models, smoking (RR = 1.9, P < .001 at 12 months; RR = 1.5, P = .043 at 24 months) and nonsurgical treatment (RR = 1.7, P < .001 at 12 months; RR = 1.8, P = .003 at 24 months) predicted long-term opioid continuation. Among participants not using opioids at baseline, incident use was reported by 8% at 12 months and 7% at 24 months. We found no significant predictors of incident use at 12 or 24 months in the main models. In conclusion, nonsurgical treatment and smoking independently predicted long-term continued opioid use. To our knowledge, this is the first longitudinal study to assess predictors of long-term and incident opioid use among patients with lumbar spine conditions.PerspectiveThis longitudinal study of patients with disc herniation or spinal stenosis found that nonsurgical treatment and smoking predicted long-term self-reported opioid use. The greater risk of opioid continuation with nonsurgical therapy may be helpful in decision-making about treatment. The relationship between opioid use, smoking, and other substance use deserves further study.     

The association between external-ground-reaction force and knee-joint kinetics during partial- and full-weight-bearing gait

BackgroundProgressive weight-bearing is recommended following autologous chondrocyte implantation. This weight-bearing program assumes that increasing external loads experienced at the foot during gait are closely related to external-knee-joint moments. We investigated this relationship, and examined other variables that may contribute to knee-joint kinetics of which the clinician can modify using practical instruction within a clinical setting.MethodsGait analysis was performed in 51 patients following autologous chondrocyte implantation, during various partial- and full-weight-bearing conditions. The contribution of ground-reaction force, kinematic and spatio-temporal gait parameters to external-knee moments was investigated within weight-bearing levels less than 60%, between 60% and 90% and more than 90% of individual body weight.FindingsThere was no association between peak-ground-reaction force and the knee-adduction moment within the 60–90% and more than 90% weight-bearing conditions, nor the peak-knee-flexion moment at less than 60% weight-bearing. Peak-ground-reaction force accounted for no more than 21.4% and 18.6% of the variance in the knee-adduction and flexion moments, respectively, within any weight-bearing condition, while the combination of peak-ground-reaction force, kinematic and spatio-temporal parameters investigated accounted for no more than 39.7% and 52.2%, respectively. Foot-progression angle and knee-flexion during weight acceptance accounted for a significant (P < 0.05) portion of the variance in external-knee moments, particularly at higher levels of weight-bearing.InterpretationA large amount of variance in knee moments may be attributed to variables other than external loads, some of which can be modified by the clinician. Clinically, this is important for any therapist implementing progressive weight-bearing protocols.     

脊柱内镜辅助斜外侧椎间融合术与经椎间孔腰椎椎体间融合术治疗腰椎不稳伴腰椎间盘突出症的疗效观察

目的 探究脊柱内镜辅助斜外侧椎间融合术（OLIF）与经椎间孔腰椎椎体间融合术（TLIF）治疗腰椎不稳伴腰椎间盘突出症的疗效。方法 选取2017年9月-2019年8月该院诊治的腰椎不稳伴腰椎间盘突出症的患者87例,根据不同手术方式分为OLIF组与TLIF组,OLIF组44例,TLIF组43例。OLIF组患者选用脊柱内镜辅助OLIF方式进行手术,TLIF组患者选用脊柱内镜辅助TLIF方式进行手术。比较两组患者术前、术后和末次随访的视觉模拟评分（VAS）、Oswestry功能障碍指数（ODI）、影像学参数（腰椎矢状位Cobb角、腰椎冠状位Cobb角以及顶椎中心偏移距离）,比较两组患者初次下床行走时间、住院时间、融合率、塌陷率和并发症发生率,评估两组患者治疗效果。结果 时间上,术前、术后和末次随访时VAS和ODI比较,差异均有统计学意义（P <0.05）。组别上,术前、术后和末次随访时OLIF组与TLIF组VAS和ODI比较,差异均无统计学意义（P> 0.05）;OLIF组和TLIF组腰椎矢状位Cobb角大于手术前,腰椎冠状位Cobb角以及顶椎中心偏移距离小于术前,差异均有统计学意...     

Neuromechanical gait adaptations in women with joint hypermobility — An exploratory study

BackgroundJoint hypermobility is known to be associated with joint and muscle pain, joint instability and osteoarthritis. Previous work suggested that those individuals present an altered neuromuscular behavior during activities such as level walking. Therefore, the aim of this study was to explore the differences in ground reaction forces, temporal parameters and muscle activation patterns during gait between normomobile and hypermobile women, including symptomatic and asymptomatic hypermobile individuals.MethodsA total of 195 women were included in this cross-sectional study, including 67 normomobile (mean 24.8 [SD 5.4] years) and 128 hypermobile (mean 25.8 [SD 5.4] years), of which 56 were further classified as symptomatic and 47 as asymptomatic. The remaining 25 subjects could not be further classified. Ground reaction forces and muscle activation from six leg muscles were measured while the subjects walked at a self-selected speed on an instrumented walkway. Temporal parameters were derived from ground reaction forces and a foot accelerometer. The normomobile and hypermobile groups were compared using independent samples t-tests, whereas the normomobile, symptomatic and asymptomatic hypermobile groups were compared using one-way ANOVAs with Tukey post-hoc tests (significance level = 0.05).FindingsSwing phase duration was higher among hypermobile (P = 0.005) and symptomatic hypermobile (P = 0.018) compared to normomobile women. The vastus medialis (P = 0.049) and lateralis (P = 0.030) and medial gastrocnemius (P = 0.011) muscles showed higher mean activation levels during stance in the hypermobile compared to the normomobile group.InterpretationHypermobile women might alter their gait pattern in order to stabilize their knee joint.