Weight-bearing Symmetry Research Articles

Effects of Mirror Feedback on Upright Stance Control in Elderly Transfemoral Amputees

Hlavackova P, Fristios J, Cuisinier R, Pinsault N, Janura M, Vuillerme N. Effects of mirror feedback on upright stance control in elderly transfemoral amputees. Objective To investigate the effects of mirror feedback on upright stance control in elderly transfemoral amputees. Design Before and after intervention trials. Setting University medical bioengineering laboratory. Participants Elderly transfemoral amputees (N=12). Interventions Participants were asked to stand upright, as immobile as possible, in 2 Eyes-open and Mirror-feedback experimental conditions. The latter experimental condition consisted of supplying the participants with their frontal reflection by positioning a mirror in front of them. Main Outcome Measures Weight-bearing symmetry and the displacements of the center of foot pressure under the nonaffected limb and the prosthetic limb. Results Mirror feedback did not modify weight-bearing symmetry and had different effects on the center of foot pressure displacements under the nonaffected limb and prosthetic limb: a decreased center of foot pressure surface area was observed in the Mirror-feedback condition relative to the Eyes-open condition under the nonaffected limb, whereas no significant difference between the Eyes-open condition and the Mirror-feedback condition was observed under the prosthetic limb. Conclusions Results suggest that elderly transfemoral amputees were able to integrate augmented visual biofeedback through the use of mirror-reflected body image to improve their upright stance control. The present findings could have implications for clinical practice and rehabilitation.

Effects of Ankle-Foot Orthoses for Children with Hemiplegia on Weight-Bearing and Functional Ability

To compare the effects of a leaf spring ankle-foot orthosis (LAFO) and a hinged AFO with plantar flexion stop with that of shoe only on weight-bearing and function in children with hemiplegia. The study used an experimental single-subject alternating treatment design with replication. Outcomes measured were weight-bearing symmetry, weight-bearing on the hemiplegic rear foot compared with that of the forefoot, functional ability, and child and parent preference. Both AFOs increased relative contact area of the hemiplegic foot. The LAFO increased relative force through the hemiplegic foot. There was increased pressure through the rear foot, time spent on the rear foot, and force through the forefoot. Rear foot contact area increased in the LAFO. Neither AFO affected function. Patient preference for AFO condition was inconsistent. Both AFOs increased weight-bearing through the hemiplegic foot and rear foot, indicative of potential benefit to growth. Neither the LAFO nor the hinged AFO with plantar flexion stop improved function of the children.

Effects of Ankle Joint Mobilizations in Adults Poststroke: A Pilot Study

Kluding PM, Santos M. Effects of ankle joint mobilizations in adults poststroke: a pilot study. Objective To compare the effect of 2 interventions on ankle mobility, ankle kinematics, and weight-bearing symmetry during functional activities in subjects with hemiparesis after a stroke. Design Randomized trial. Setting Academic medical center. Participants A convenience sample of 16 subjects with hemiparesis after stroke (mean age, 55.2y; mean time since stroke, 21.4mo). Intervention Subjects received 8 sessions over 4 weeks of either functional task practice combined with ankle joint mobilizations, or functional task practice only. Main Outcome Measures Changes in ankle range of motion (ROM) (not blinded), ankle kinematics during sit-to-stand (STS) and gait, and lower-extremity weight-bearing symmetry during STS and static standing. Results The combined intervention group gained 5.7°±3.1° in passive ankle ROM compared with 0.2°±2.6° in the functional practice only group (95% confidence interval [CI], 2.5–8.6; P<.01). No significant changes in ankle kinematics or weight bearing during static standing were noted in either group. The functional practice group decreased differences in weight bearing during STS by 9.5%±6.47%, whereas the combined intervention group increased this difference by 3.37%±5.29% (95% CI, 3.26–19.46; P=.01). Conclusions The increase in ankle motion did not improve joint kinematics and may have prevented improvement in weight-bearing symmetry.

Effects of lower limb intensive mass practice in poststroke patients: single-subject experimental design with long-term follow-up

Objective: To investigate the effects of two weeks of intensive mass practice with a constraint-induced movement therapy approach for the lower extremity in five chronic poststroke patients, and the persistence of effects at three and six months. Design: A single-subject experimental design (SSED) was used with an AB design and follow-ups three and six months later. Setting: Outpatient rehabilitation at Torsby Hospital in Sweden. Main measures: Motor function in lower extremity, mobility, dynamic balance, weight-bearing symmetry and walking ability were measured on six occasions during two weeks (A phase), with the Fugl-Meyer assessment for lower extremity, the Timed Up and Go, the Step Test, the Timed Walking Test and the Six-Minute Walk Test. During the intervention's B phase, six measurements were performed with the same time intervals as in the A phase. There were follow-ups three and six months later. Intervention: The intervention (B phase) consisted of bicycling, training in water, strength training, standing weight-bearing, walking up and down stairs, walking indoors and outdoors and flexibility training of the lower extremity, on all weekdays, 6 h a day for two weeks. Results: The results showed improvements in 23/30 variables (77%), 12 of them statistically significant (52%). At follow-up, 22/23 improvements persisted. For example, three of five subjects walked significantly further after the intervention and the follow-ups showed that they still walked further than before the intervention. Conclusion: Intensive mass practice with constraint-induced movement therapy for the lower extremity can improve motor function, mobility, dynamic balance, weight-bearing symmetry and walking ability in chronic poststroke patients.Long-term follow-up showed that the effects persisted for these five subjects.

An intensive massed practice approach to retraining balance post-stroke

Falls are highly prevalent and a significant source of complications post-stroke. This study tested the efficacy of standard physical therapy (based on the task-oriented approach) delivered in a massed practice paradigm. The purpose of this study was to test if the intensive massed practice intervention (6h/day for 2 consecutive weeks) could significantly improve balance function post-stroke. A single-subject multiple baseline design across subjects with probes was utilized with ten subjects with chronic stroke disability. Clinical tests and time to stabilization (TTS) of the center of pressure in response to a platform perturbation were calculated during baseline, intervention, and the maintenance phases. The ability of the subjects to recover from a balance threat improved, with mean TTS decreasing from 2.35 +/- .51 s during baseline, to 1.58+/-.23s during training, and further still to 1.45 +/- .29 s during the maintenance phase, ending 3 months post-intervention. Clinical findings demonstrated improvements in anticipatory and steady-state balance control. In addition weight-bearing symmetry improved and the number of falls sustained reduced. Intensive massed practice of standard physical therapy produced significant results in balance retraining with patients post-stroke. Our finding support the need to offer additional practice to maximize the efficacy of physical therapy sessions.

Muscle strength and weight-bearing symmetry relate to sit-to-stand performance in individuals with stroke

This study investigated the relationship of lower extremity joint torques and weight-bearing symmetry to sit-to-stand (STS) performance in individuals with chronic stroke. A motion analysis system and two force plates measured STS duration and weight-bearing symmetry (determined by ground reaction forces) during three self-paced and three fast-paced conditions. An isokinetic dynamometer measured maximum concentric joint torques of the paretic and non-paretic ankle, knee, and hip, which were normalized by body mass. Pearson correlations indicated that (a) paretic ankle dorsiflexion and knee extension torques related to the duration of the self-paced STS condition (r = -0.450, -0.716, respectively), (b) paretic ankle dorsiflexion, plantar flexion, and knee extension torques related to the duration of the fast-paced STS condition (r = -0.466, -0.616, -0.736, respectively), and (c) greater weight-bearing symmetry related to faster STS performance for both self-paced and fast-paced STS conditions (r = -0.565, -0.564, respectively) (P < 0.05). This evidence suggests that paretic muscle strength and the ability to load the paretic limb are important factors underlying the ability to rise from a chair in individuals with chronic stroke.

Immediate Improvements in Side-to-Side Weight Bearing and Iliac Crest Symmetry After Manipulation in Patients with Low Back Pain

Background Although there is good evidence that spinal manipulation is an effective treatment to improve pain and function for patients with low back pain (LBP), there is little evidence to support the mechanism by which manipulation works. Objectives To determine if iliac crest (IC) and weight-bearing (WB) symmetry improve after spinal manipulation and to determine if improvements in IC and WB symmetry are associated with improvements in pain and function in patients with low back pain. Design Single group, within-subjects, repeated measures design. Method Thirty consecutive patients (mean age = 40±13) who came to a spine specialty center for treatment of acute or chronic LBP and who would be receiving spinal manipulation participated in the study (14 male patients). Patients completed a series of self-report measures of pain and function and received a standardized physical examination, including the assessment of IC and WB symmetry. Patients received a standardized manipulative intervention, and immediate and 3- to 4-day follow-up examinations were performed by a blinded examiner. Paired t tests were performed to determine within-group changes, and Pearson product moment correlation coefficients were calculated to determine the relationship between improvements in IC and WB symmetry and improvements in pain and function. To control for the potential that an association between changes in IC and/or WB symmetry and changes in pain and function could be confounded by the baseline outcome measure, simultaneous linear regression was performed on any significant correlation. Partial F tests were used to determine if the additional explained variability was significant. Results Patients with LBP demonstrated significant improvements in IC and WB symmetry after manipulation ( P<.001). Improvements in WB symmetry were associated with improvements in the patients' self-reported levels of pain 3 to 4 days after manipulation ( r=.5, P=.007). Based on the significant association between improvements in WB symmetry and improvements in pain, the final pain score was regressed on the change in WB symmetry, after controlling for the baseline level of pain. The addition of the change in WB symmetry explained a 10% additional increase in variability in the patient's level of pain at the 3- to 4-day follow-up ( P = .01). No relationship was found between improvements in IC and WB symmetry and improvements in function as determined by the Oswestry Disability Questionnaire 3 to 4 days after manipulation. Conclusion IC and WB symmetry improved immediately after spinal manipulation. Improvements in WB symmetry were related to improvements in the patients' self-reported levels of pain, even after controlling for the baseline level of pain. Improvements in IC and WB symmetry were not related to changes in function. The results of this study provide initial data to elucidate how manipulation may work to improve pain and function in patients with LBP.

Poster 2: Postural control in elderly women with knee osteoarthritis

Objective: To examine the effect of painful knee osteoarthritis on baseline balance and the relationship between balance measures and clinical measures. Design: Cross-sectional, observational, and controlled study. Setting: Sports medicine laboratory. Participants: 22 healthy women and 26 women with unilateral knee pain (age range, 60–80y). Interventions: Not applicable. Main Outcome Measures: Outcome measures included 6 force platform measures, ambulatory and transfer knee-pain intensity score (visual analog scale [VAS]), and disease burden (Kellgren-Lawrence score). The force platform measures obtained using the Balance Master System, which included weight-bearing symmetry, sway, and movement time during performing 6 tasks: weight bearing and squat, unilateral stance with eyes open, rhythmic weight shift, sit to stand, tandem walk, and step up and over. Results: On-axis velocity (deg/s) and directional control (%) in front and back rhythmic weight shift, and rising index (% body weight) in sit to stand were lower in women with unilateral knee pain ( P<.05). Center of gravity (COG) sway velocity (deg/s) during unilateral stance in painful legs was greater than that in subjects’ other legs. The weight of women with unilateral knee pain loaded less on the painful side during 30° and 60° squats and during sit to stand ( P<.05). Movement time during step up and over on the painful side was longer than that on the pain-free side ( P<.05). Ambulatory knee-pain intensity (VAS) had a linear relationship with the movement time during step up and over on the painful side ( r=.42). Conclusion: Avoidance of pain associated with limb loading and decline in postural control ability were demonstrated in elderly women with unilateral knee pain. Based on these results, further studies should be carried out to correlate the avoidance and decline with the falls in patients with painful knee osteoarthritis.

The effect of shoe wedges and lifts on symmetry of stance and weight bearing in hemiparetic individuals

Rodriguez GM, Aruin AS. The effect of shoe wedges and lifts on symmetry of stance and weight bearing in hemiparetic individuals. Arch Phys Med Rehabil 2002;83:478-82. Objective: To determine the effect of shoe wedges and lifts on symmetry of stance and weight bearing in hemiparetic individuals. Design: Weight bearing on the paretic side was measured in patients with hemiparesis during quiet standing and in conditions of compelled weight shift. Setting: Free-standing acute inpatient rehabilitation hospital. Participants: Nine individuals with hemiparesis as a result of unilateral stroke who were able to stand for 3 to 5 minutes without assistance or rest, and satisfied other inclusion criteria. Interventions: Compelled shift of the body weight was induced with different shoe wedges (5°, 7.5°, 12.5°) or shoe lifts (0.6, 0.9, 1.2cm), which extended under the entire shoe of the unaffected limb. Weight-bearing symmetry scores were used to characterize the symmetry of stance. Main Outcome Measures: Weight-bearing symmetry scores. Results: Without a shoe wedge or a shoe lift, weight-bearing symmetry was characterized by underloading of the paretic limb (39.90% ±.80% of body weight). Weight shift induced by shoe wedges or shoe lifts applied to the unaffected limb promoted improved symmetry of weight bearing and stance. A shoe wedge of 5° provided the most symmetrical weight distribution (51.44% ± 1.88% of body weight). Conclusion: Shoe wedges and shoe lifts under the unaffected limb induced compelled weight shift toward the paretic limb, resulting in improved symmetry of stance of individuals with mild hemiparesis. We suggest that improved symmetry of bipedal standing obtained with a shoe wedge or a shoe lift applied to the unaffected limb can help overcome the learned disuse of the affected limb. We further suggest that weight distribution induced by shoe wedges or shoe lifts may help in the treatment of ambulatory hemiparetic individuals with asymmetrical stance caused by unilateral stroke. © 2002 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation