Discriminant Accuracy of Standing Balance Tests for the Level of Gait Dependency in Hospitalized Patients with Alzheimer's Disease.

INTRODUCTION: When determining the level of gait independence in patients with Alzheimer's disease (AD), detailed functional assessment is difficult in some patients. The previous literature has suggested simple standing balance tests for patients with AD due to their ease of implementation in clinical practice and relevance to gait. However, their usefulness for discriminating the level of gait independence remains unclear. This study aimed to investigate the discrimination accuracy of a simple standing balance test in the level of gait independence among hospitalized patients with AD. METHODS: This cross-sectional study was a post hoc analysis of a study conducted on 63 inpatients with AD in a single hospital. Participants were divided into three groups according to their level of gait independence: independent, modified independent (independent, walking with walking aids), and dependent groups (supervision). Gait independence was determined using the Functional Independence Measure. Four standing balance tests were used - closed-leg, semi-tandem, tandem, and one-leg standings - and the discrimination accuracy of each test was calculated by receiver operating characteristic analysis. RESULTS: One-leg standing was best at discriminating between the independent and modified independent groups (positive predictive value = 80.0%, negative predictive value = 94.1%). Tandem standing was best at discriminating between the modified independent and dependent groups (positive predictive value = 74.1%, negative predictive value = 93.3%). CONCLUSION: A simple standing balance test may assist in the determining level of gait independence in patients with AD when it is difficult to perform a mobility assessment.

Influence of Spinal Sagittal Alignment in Sitting Posture on the Swallowing Speed of Older Adult Women: A Cross-Sectional Study.

Thoracolumbar kyphosis in sitting posture is associated with forward head posture and may adversely affect swallowing function. However, few studies have investigated the effect of spinal alignment in the sitting posture on the swallowing function of older adults. This cross-sectional study aimed to investigate whether spinal alignment in the sitting posture influences the swallowing function of older adult women. Overall, 18 older adult women (mean age, 69.78 ± 3.66 years) without dysphagia were enrolled. Participants were positioned in two sitting postures, namely, comfortable sitting (CS) and thoracic upright sitting (TUS). In each sitting posture, the kyphosis index (using a flexicurve), sagittal angles (head, cervical, shoulder, and pelvic angles; using a digital camera), and cervical range of motion (ROM) were evaluated. Swallowing speed (100-mL water swallowing test), maximum tongue pressure (MTP), and oral diadochokinesis (ODK) were also evaluated. Compared with TUS, CS showed a greater kyphosis index, anterior head translation, and posterior pelvic tilt. CS had greater flexion (p < 0.001) and less extension (p < 0.001) of cervical ROM than TUS. Swallowing speed was significantly decreased in CS compared with TUS (p = 0.008). MTP and ODK were not significantly different between CS and TUS. Thus, changes in sitting posture with spinal alignment may affect swallowing speed. Consequently, adjustments to reduce sitting postural kyphosis in older adult women may improve swallowing speed.

Influence of the menstrual cycle on static and dynamic kinematics of the foot medial longitudinal arch.

BACKGROUND: In women, the laxity of the plantar fascia increases during the ovulation phase of the menstrual cycle. Although it is possible that this increased laxity results in a decreased height of the foot in the medial longitudinal arch and exacerbates symptoms of several overuse injuries of the lower extremity, the influence of the menstrual cycle on static and dynamic kinematics of the medial longitudinal arch is unclear. The purpose of this study was to confirm that the medial longitudinal arch height during static standing, gait, and landing decrease during the menstrual cycle ovulation phase. METHODS: Participants in this study were 16 female college students with normal menstrual cycles and 16 male college students. Navicular height in the static standing position was measured using a three-dimensional foot scanner. Kinematics of the medial longitudinal arch during gait and landing were measured using a three-dimensional motion capture system to determine the navicular height at initial contact, minimal navicular height, and dynamic navicular drop. In all measurements, female participants were tested twice during the course of one complete menstrual cycle: once during the follicular phase and once during the ovulation phase. Male participants were tested twice with an interval of ≥1 week and <2 weeks. RESULTS: In women, navicular height in the static standing position significantly decreased during the ovulation phase compared with follicular phase (mean difference [95% confidence interval] = 2.1 [0.9-3.4] mm; p = 0.002), whereas men showed no statistical difference between the first and second measurements. In both men and women, no statistical differences were identified for the dynamic medial longitudinal arch kinematics measured during gait and landing. CONCLUSIONS: Navicular height in the static standing position slightly decreased during the ovulation phase.

Extraction of the pull force from inertial sensors during the pull test for Parkinson's disease: A reliability study.

OBJECTIVE: To examine the inter- and intra-rater reliability of the pull test in patients with Parkinson's disease (PD) using the extracted pull force. METHODS: In this inter- and intra-rater reliability study, two raters performed a pull test on 30 patients with PD. The pull force was quantified using inertial sensors attached to the rater's right hand and the patient's lower trunk. In this study, the pull force was calculated as an extracted three-dimensional vector quantity, the resultant acceleration, and was expressed in m/s2. Inter- and intra-rater reliabilities were analyzed using the interclass correlation coefficient (ICC) for the pull force and Cohen's weighted kappa (κw) for the pull test score. Furthermore, Bland-Altman analysis was used to investigate systematic errors. RESULTS: The inter- and intra-rater reliability of the pull force was very poor (ICC = 0.033-0.214). Bland-Altman analysis revealed no systematic errors in the pull forces between the two test points. Conversely, κw for the pull test scores ranged from 0.763 to 0.920, indicating substantial to almost perfect agreement. CONCLUSION: The pull test score was reliable despite variations in the quantified pull force for inter- and intra-rater reliability. Our findings suggest that the pull test is a robust tool for evaluating postural instability in patients with PD and that the pull force probably does not affect scoring performance.

Comparison of foot kinematics and ground reaction force characteristics during walking in individuals with highly and mildly pronated feet.

BACKGROUND: Individuals with highly pronated feet (PF) are more prone to lower extremity injuries than those with mildly PF. However, whether foot kinematics and ground reaction force (GRF) characteristics differ according to the severity of PF deformity is unclear. RESEARCH QUESTION: Are there differences in foot kinematics and GRF characteristics during walking between individuals with mildly PF and those with highly PF? METHODS: Ten individuals with mildly PF and 10 with highly PF (six-item foot posture index scores: 6-9 and 10-12 points, respectively) participated in this study. A three-dimensional motion analysis system measured participants' foot kinematics and GRF characteristics during gait trials. RESULTS: Participants with highly PF exhibited significantly lower medial longitudinal arch heights than those with mildly PF from 0 % to 90 % of the stance phase (p < 0.05). No significant differences were observed in any of the angles between the foot segments. Additionally, participants with highly PF exhibited significantly larger posterior GRF than those with mildly PF from 2 % to 7 % of the stance phase (p < 0.05). Participants with highly PF also exhibited significantly larger anterior GRF than those with mildly PF, from 62 % to 82 % of the stance phase (p < 0.05). SIGNIFICANCE: The results of this study suggest that the more severe the PF deformity, the more inefficient the foot ground force transmission, and the stronger the load applied to the foot. These results may be related to the higher incidence of lower extremity injuries in individuals with highly PF than in those with mildly PF.

Effects of Nutritional Support Combined with Neuromuscular Electrical Stimulation on Muscle Strength and Thickness: A Randomized Controlled Trial in Healthy Young Adult Males.

In the management of post-injury patients with activity limitations, methods to prevent musculoskeletal disorders and hasten recovery are important. This randomized controlled, single-blinded study was a preliminary investigation of the combined effect of nutritional support with neuromuscular electrical stimulation (NMES) on muscle strength and thickness. Healthy young adult males (median age, 21 years) were enrolled; each of their hands was randomly assigned to one of the following four groups: Placebo, Nutrition, NMES, and Nutrition + NMES. All participants received whey protein or placebo (3x/week for 6 weeks) and NMES training (3x/week for 6 weeks) on the abductor digiti minimi (ADM) muscle of either the left or right hand. ADM muscle strength and thickness were analyzed at baseline and at week 7. We analyzed 38 hands (9 Placebo, 10 Nutrition, 9 NMES, 10 Nutrition + NMES). There was significantly greater muscle strengthening in the Nutrition + NMES group compared to the Placebo group or the NMES group, but no significant difference in gain of muscle thickness. The combined intervention may be effective in improving muscle strength. Future clinical trials targeting various muscles after sports-related injuries are warranted.

Combining Physical and Cognitive Functions to Discriminate Level of Gait Independence in Hospitalized Patients with Alzheimer's Disease.

INTRODUCTION: Both physical and cognitive functions are required to be assessed to determine the level of gait independence in patients with Alzheimer's disease (AD); nonetheless, a method to achieve this assessment has not been established. This study aimed to investigate the accuracy of an assessment method that combined muscle strength, balance ability, and cognitive function parameters in discriminating the level of gait independence in a real-world setting in hospitalized patients with AD. METHODS: In this cross-sectional study, 63 patients with AD (mean age: 86.1 ± 5.8 years) were classified into three groups according to their gait level: independent, modified independent (independent walking with walking aids), and dependent groups. Discrimination accuracy was calculated for single items of muscle strength, balance ability, and cognitive function tests and for combinations of each. RESULTS: The combined accuracy of muscle strength, balance ability, and cognitive function had a positive predictive value of 100.0% and a negative predictive value of 67.7% between the independent and modified independent groups. The positive and negative predictive values were 100.0% and 72.4%, respectively, between the modified independent and dependent groups. CONCLUSION: This study emphasizes the importance of assessing the level of gait independence in a real-world setting in patients with AD from the perspective of both physical and cognitive functions and proposes a novel method for discriminating an optimal state.

Effect of Spinal Sagittal Alignment in Sitting Posture on Swallowing Function in Healthy Adult Women: A Cross-Sectional Study.

Swallowing function is both directly and indirectly related to postures, such as head and cervical angle and body position. However, the effects of different sitting postures on oropharyngeal swallowing have not been investigated. This study aimed to investigate whether the change in thoracolumbar alignment affected the oropharyngeal swallowing. A total of 58 healthy adult women (mean age 22.2 ± 1.67 years) without dysphagia were enrolled in this cross-sectional study. Participants were positioned in three sitting postures: comfortable sitting (CS), thoracic upright sitting (TUS), and slump sitting (SS). In each sitting posture, the kyphosis index (using a flexicurve), head and cervical angles (using a digital camera), swallowing speed (100-ml water swallowing test), and oral and articulatory function [by maximum tongue pressure (MTP) and oral diadochokinesis (ODK)] were evaluated. SS showed the largest kyphosis index and was associated with a greater anterior translation of the head. Swallowing speed was significantly decreased in SS compared with CS (p = 0.002) and TUS (p = 0.020) and ODK was significantly decreased in SS compared with other postures, for both /ta/ (p = 0.004) and /ka/ (p < 0.001) syllables. Further, MTP tended to decrease in SS compared with TUS (p = 0.064). Our results suggest that changes in sitting posture with different thoracolumbar alignments affect swallowing speed and oral and articulatory function. Consequently, adjustments to reduce sitting postural kyphosis may improve swallowing speed and oral and articulatory function.

Interventions focusing on learning pre-transfer wheelchair manipulation in a patient with severe Alzheimer's disease: a case report.

BACKGROUND: Independence of transfer is important for the daily activities of wheelchair users. A critical step in performing this transfer includes a pre-transfer wheelchair manipulation, and patients with Alzheimer's disease (AD) experience difficulties in learning these tasks. In this report, we present the results of a treatment focused on learning pre-transfer wheelchair manipulation and its learning course in a patient with severe AD. CASE DESCRIPTION: The patient was a 92-year-old woman with severe AD during hospitalization in a long-term care ward. Since her cognitive function was highly compromised, she required assistance for pre-transfer wheelchair manipulation. Physiotherapists implemented a treatment plan that incorporated post-behavioral praise into a practice combining errorless learning and spaced retrieval training for pre-transfer wheelchair manipulation. OUTCOMES: The patient was able to accurately perform pre-transfer wheelchair manipulation in the seventh treatment session and achieved transfer independence after 12 physiotherapy sessions. CONCLUSION: This case report suggests that practicing combined errorless learning, spaced retrieval training, and post-behavioral praise was helpful as a treatment modality for an individual with severe AD for wheelchair manipulation learning before transfer.

The power of instruction on retropulsion: A pilot randomized controlled trial of therapeutic exercise focused on ankle joint movement in Parkinson's disease.

Introduction: Although retropulsion is a serious complication of Parkinson's disease (PD), it is unknown whether ankle joint movement patterns can be targeted to treat retropulsion. The primary aim of this study was to investigate the effectiveness of therapeutic exercise focused on instructions regarding ankle joint movement on retropulsion in PD. Methods: Twenty patients with moderate PD were randomly allocated to the experimental intervention (INSTR) or control groups. The INSTR group received a 2-week therapeutic exercise program (40 min/day, five times/week) that involved repeated backward pulls on the shoulders with instructions to land on the toes as a response, and the control group received the same intervention without the instructions. The primary outcome was the difference in changes from baseline in the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS part III) score between the study groups at weeks 1 and 2. Results: The improvement in the MDS-UPDRS part III scores was significantly greater for the INSTR group in the week 1 (p = 0.033, pη2 = 0.241) and week 2 (p = 0.004, pη2 = 0.401) assessments. However, the provision of instructions to land on the toes as a backward response induced improvement in the only scores related to the backward response, and no significant between-group differences were observed in the other outcomes. Conclusion: The 2-week therapeutic exercise program with instructions to treat retropulsion improved the backward response. Trial registration: UMIN-CTR, UMIN000042722.

Classification of medial longitudinal arch kinematics during running and characteristics of foot muscle morphology in novice runners with pronated foot.

BACKGROUND: Novice runners with pronated feet are at an increased risk of running-related injuries. However, not all runners with pronated feet have increased foot pronation during running. Moreover, although foot muscle morphology is related to static foot alignment, the relationship between foot muscle morphology and foot kinematics during running remains unclear. We aimed to determine foot kinematic patterns during running among novice runners with pronated feet and the presence of a relationship between these foot kinematic patterns and foot muscle morphology. METHODS: Twenty-one novice runners with pronated feet participated in this study, and data on 39 lower limbs were collected. Data on foot kinematics during running (rearfoot strike) were collected using a three-dimensional motion capture system in terms of navicular height (NH) at initial contact and dynamic navicular drop (DND). A hierarchical cluster analysis method was used to identify the optimal number of clusters based on these two foot-related kinematic variables. Following identification of the clusters, differences in cluster variables and cross-sectional areas of selected foot muscles assessed using ultrasonography in each cluster were examined. The muscles of interest included the abductor hallucis, flexor hallucis brevis and longus, flexor digitorum brevis and longus, and peroneus longus. RESULTS: Three subgroups were identified based on foot kinematics during running: cluster 1, lowest NH at initial contact and larger DND; cluster 2, moderate NH at initial contact and smaller DND; and cluster 3, highest NH at initial contact and larger DND. Clusters 1 and 3 had a larger abductor hallucis compared with cluster 2, and cluster 3 had a larger flexor hallucis brevis compared with cluster 2. SIGNIFICANCE: These subgroups may differ in terms of resistance to and type of running-related injury. Moreover, foot kinematics during running is possibly impacted by the morphology and function of medial intrinsic foot muscles.

Relationship between foot muscle morphology and severity of pronated foot deformity and foot kinematics during gait: A preliminary study.

BACKGROUND: The morphology of foot muscles that support the medial longitudinal arch differs between normal and pronated feet. The degree to which the difference depends on the severity of the pronated foot deformity is unclear. In the clinical setting, however, to reduce the pronated deformity, muscle-strengthening exercises are performed. RESEARCH QUESTION: Does a relationship exist between foot muscle morphology and severity of the pronated foot deformity and foot kinematics during gait? METHODS: Using the six-item foot posture index (FPI-6), 26 study participants were assessed for their foot posture and divided into two groups of 13 participants each based on the FPI-6 score: pronated foot group (with a score of 6-9) and highly pronated foot group (with a score of 10-12). Select foot muscles were scanned with ultrasonography, and muscle thicknesses were measured. The following were the muscles of interest: abductor hallucis, flexor hallucis brevis and longus, flexor digitorum brevis and longus, and peroneus longus. Foot kinematic data during gait was collected using a three-dimensional motion capture system as a dynamic navicular drop. RESULTS: No between-group differences were noted for muscle thickness and dynamic navicular drop. However, the abductor hallucis and flexor hallucis brevis thicknesses were correlated with the dynamic navicular drop, but not with the severity of the pronated foot deformity. SIGNIFICANCE: In individuals with pronated foot deformity, more developed abductor hallucis and flexor hallucis brevis muscles may reduce the dynamic navicular drop that represents the degree of medial longitudinal arch deformation during the stance phase of gait.

Intrinsic foot muscle strengthening exercises with electromyographic biofeedback achieve increased toe flexor strength in older adults: A pilot randomized controlled trial.

BACKGROUND: Toe flexor strength is important for preventing older adults from falling. Although intrinsic foot muscles are the main determinants of toe flexor strength, exercises for strengthening these muscles are difficult for older adults. This study therefore aimed to determine whether the use of electromyographic biofeedback helps older adults to perform intrinsic foot muscle strengthening exercises. METHODS: This randomized controlled trial had two parallel arms. Participants were randomly allocated to the control group or the electromyographic biofeedback group. Control participants performed two progressive intrinsic foot muscle strengthening exercises twice a week for 6 weeks. Participants in the other group performed these exercises assisted by electromyographic biofeedback. Primary outcome measures were changes in toe flexor strength and the timed up-and-go and functional reach tests (the latter two being balance tests). FINDINGS: Altogether, 23 older adults were randomized to the control group (n = 12) or the electromyographic biofeedback group (n = 11). After the 6-week intervention, toe flexor strength on the dominant side increased in both groups (P < 0.017). However, toe flexor strength on the nondominant side increased only in the electromyographic biofeedback group (P < 0.017), with a large effect size of 1.5. There were no changes in the two balance tests. Three of the control group and two of the electromyographic biofeedback group were lost to follow- up. INTERPRETATION: Our results indicate that, the use of electromyographic biofeedback can enhance the effect of intrinsic foot muscle strengthening exercises on the nondominant side in older adults. CLINICAL TRIAL REGISTRATION NUMBER: UMIN000036521.

Effects of plantar intrinsic foot muscle strengthening exercise on static and dynamic foot kinematics: A pilot randomized controlled single-blind trial in individuals with pes planus.

BACKGROUND: No reliable evidence has confirmed whether plantar intrinsic foot muscle strengthening exercises improve static and dynamic foot kinematics in individuals with pes planus. RESEARCH QUESTION: Does the short-foot exercise affect static foot alignment and foot kinematics during gait in individuals with pes planus? METHODS: This was a randomized controlled single-blind trial involving 20 participants with pes planus who were randomly allocated to a short-foot exercise group (exercise) or a control group (controls). Exercise patients performed a progressive short-foot exercise three times per week for 8 weeks; controls received no intervention. Before and after the 8-week intervention, foot kinematics during gait, including dynamic navicular drop-the difference between navicular height at heel strike and the minimum value-and the time at which navicular height reached its minimum value were assessed, using three-dimensional motion analysis. We assessed static foot alignment by foot posture index and navicular drop test, and the thickness of the intrinsic and extrinsic foot muscles using ultrasound. All measurements were performed by one investigator (KO) blinded to the participants' allocation. RESULTS: After the 8-week intervention in the exercise group, foot posture index scores with regard to calcaneal inversion/eversion improved significantly (p < 0.05). Moreover, the time required for navicular height to reach the minimum value decreased significantly (p < 0.01). SIGNIFICANCE: For individuals with pes planus, the short-foot exercise effectively corrected static foot alignment and temporal parameters of foot kinematics during gait. This temporal change, which shortens the time for navicular height to reach its minimum value, indicates an improved windlass mechanism. Therefore, short-foot exercise might effectively prevent or treat injuries related to the pes planus alignment.

Effect of electromyographic biofeedback on learning the short foot exercise.

BACKGROUND: The short foot (SF) exercise is a strengthening exercise for the intrinsic foot muscles that is difficult to master. OBJECTIVE: To examine the effect of three different electromyographic (EMG) biofeedback methods on learning the SF exercise. METHODS: Thirty-six healthy subjects were randomly allocated to the control group (CTG), EMG-controlled electrical stimulation group (ESG), visual EMG biofeedback group (VSG), and combination EMG-controlled electrical stimulation with visual EMG biofeedback group (CBG). The CTG practiced the SF exercise for 5 minutes using the conventional method. The other groups each used the EMG biofeedback method and the conventional method. The EMG activity of the abductor hallucis (ABH), the medial longitudinal arch (MLA) angle, and the foot length during the SF exercise were measured before and after 5 minutes of practice. RESULTS: The EMG activity of the ABH in the VSG and CBG was significantly higher than that before practice. There were no intergroup differences in MLA morphology. CONCLUSIONS: These results suggest that visual EMG biofeedback is an effective method of increasing the EMG activity of the ABH during the SF exercise in a short practice time.

The effect of additional activation of the plantar intrinsic foot muscles on foot kinematics in flat-footed subjects.

BACKGROUND: Strengthening exercises of the plantar intrinsic foot muscles (PIFMs) are often prescribed to flat-footed subjects because of the capacity of the PIFMs to support the medial longitudinal arch (MLA). However, it is unclear whether the capacity of the PIFMs to support the MLA is enough to change the foot kinematics in flat-footed subjects. To confirm this, the current study examined changes in foot kinematics in flat-footed subjects during standing and gait accompanied by changes in the activity of the PIFMs. METHODS: Eighteen flat-footed subjects were randomly assigned to an electrical stimulation group (ESG) or a control group (CG). In the ESG, electrical stimulation to the PIFMs was applied during standing and gait to simulate reinforcement of the PIFMs. Then, foot kinematics were measured using 3D motion analysis, and the amount of change from baseline (when no electrical stimulation was applied) was compared between the groups. RESULTS: In the gait analysis, the time at which the MLA height reached its minimum value was significantly later in the ESG, with no reduction in the MLA height at that time. Moreover, forefoot inversion angle and tibial external rotation angle were significantly increased in the ESG at that time. In the standing analysis, there were no significant differences between the groups. CONCLUSION: The results revealed that in flat-footed subjects, the PIFMs have the capacity to support the MLA enough to change foot kinematics during gait. Strengthening these muscles may be effective in preventing or treating lower extremity overuse injuries related to flat-foot alignment.

The effect of additional activation of the plantar intrinsic foot muscles on foot dynamics during gait.

BACKGROUND: The plantar intrinsic foot muscles (PIFMs) contribute to support the medial longitudinal arch. But the functional role of the PIFMs during dynamic activities is not clear. The purpose of this study was to examine the change in the foot dynamics during gait accompanied with the change in the PIFMs activity to determine the functional role of the PIFMs during gait. METHODS: Twenty healthy male subjects were randomly assigned to the electrical stimulation group (ESG) or control group (CG). In the ESG, the electrical stimulation to the PIFMs was provided from mid-stance to pre-swing using surface electrodes to simulate reinforcement of the PIFMs. The foot dynamics during the stance phase of gait was measured using a 3D motion analysis, and the amount of change from baseline (electrical stimulation was not provided) was compared between groups using an independent sample t-test. RESULTS: In the ESG, the timing for the navicular height to reach the minimum value was significantly later, and the vertical ground reaction force (2nd peak) significantly decreased more. There were no group differences in the amount of change from baseline on gait velocity, stance phase duration, minimum navicular height and ground reaction force in other directions. CONCLUSION: Results from this study showed that the functions of the PIFMs most likely include shock absorption and facilitation of efficient foot ground force transmission during the stance phase of gait.

Does the weakening of intrinsic foot muscles cause the decrease of medial longitudinal arch height?

[Purpose] There are no reliable evidences that the weakening of intrinsic foot muscles causes the decrease of the medial longitudinal arch (MLA) height. The purpose of this study was to confirm whether the fatigue of intrinsic foot muscles decrease the MLA height during standing and gait using 3D motion analysis system. [Subjects and Methods] Twenty healthy male subjects participated in this study. Foot kinematics was measured using an Oxford Foot Model before and after fatigue-inducing exercises of the abductor hallucis and flexor hallucis brevis muscles. [Results] Following fatigue-inducing exercise, in both standing and gait, the MLA height did not decrease but slightly increased. In addition, the reduction of a rear foot eversion angle was noted. [Conclusion] Fatigue of the abductor hallucis and flexor hallucis brevis muscles did not cause a change associated with collapsing of the MLA during both standing and gait. This suggested that the MLA support force from these muscles would be compensated by other MLA support structures, such as extrinsic foot muscles.

Effects of methods of descending stairs forwards versus backwards on knee joint force in patients with osteoarthritis of the knee: a clinical controlled study.

BACKGROUND: The aim of this study was to investigate the kinetic characteristics of compensatory backward descending movement performed by patients with osteoarthritis of the knee. METHODS: Using a three-dimensional motion analysis system, we investigated lower extremity joint angles, joint moments, joint force of the support leg in forward and backward descending movements on stairs, and joint force of the leading leg at landing in 7 female patients with osteoarthritis of the knee. RESULTS: Compared with the forward descending movement, knee joint angle, joint moment and joint force of the support leg all decreased in the backward descending movement. Joint force of the leading leg at landing was also reduced in the backward descending movement. In addition, we confirmed that the center of body mass was mainly controlled by the knee and ankle joints in the forward descending movement, and by the hip joint in the backward descending movement. CONCLUSIONS: Since it has been reported that knee flexion angle and extensor muscle strength are decreased in patients with osteoarthritis of the knee, we believe that backward descending movement is an effective method to use the hip joint to compensate for these functional defects. In addition, due to the decreased knee joint force both in the leading and support legs in backward descending movement, the effectiveness of compensatory motion for pain control and knee joint protection was also suggested.