Agreement of Gait Events Detection during Treadmill Backward Walking by Kinematic Data and Inertial Motion Units.

Backward walking (BW) is being increasingly used in neurologic and orthopedic rehabilitation as well as in sports to promote balance control as it provides a unique challenge to the sensorimotor control system. The identification of initial foot contact (IC) and terminal foot contact (TC) events is crucial for gait analysis. Data of optical motion capture (OMC) kinematics and inertial motion units (IMUs) are commonly used to detect gait events during forward walking (FW). However, the agreement between such methods during BW has not been investigated. In this study, the OMC kinematics and inertial data of 10 healthy young adults were recorded during BW and FW on a treadmill at different speeds. Gait events were measured using both kinematics and inertial data and then evaluated for agreement. Excellent reliability (Interclass Correlation > 0.9) was achieved for the identification of both IC and TC. The absolute differences between methods during BW were 18.5 ± 18.3 and 20.4 ± 15.2 ms for IC and TC, respectively, compared to 9.1 ± 9.6 and 10.0 ± 14.9 for IC and TC, respectively, during FW. The high levels of agreement between methods indicate that both may be used for some applications of BW gait analysis.

Spatiotemporal gait characteristics and ankle kinematics of backward walking in people with chronic ankle instability.

Backward walking offers a unique challenge to balance and ambulation. This study investigated the characteristics of spatiotemporal gait factors and ankle kinematics during backward walking in people with chronic ankle instability. Sixteen subjects with chronic ankle instability and 16 able-bodied controls walked on a treadmill at their self-selected speed under backward and forward walking conditions. Gait speed, cadence, double limb support percentage, stride time variability, and three-dimensional ankle kinematics were compared between groups and conditions. During backward walking, both groups had significantly slower gait speed, lower cadence, and greater stride time variability. In addition, under backward walking condition, subjects in both groups demonstrated significant sagittal and frontal kinematic alternations, such as greater dorsiflexion and inversion following initial contact (0-27.7%, 0-25.0% of gait cycle respectively, p < 0.001). However, there were no significant differences between groups in any of the measured outcomes. This indicates that subjects with chronic ankle instability adapt to self-selected speed backward walking similarly to healthy controls. Assessments with more challenging tasks, such as backward walking with dual task and backward walking at fast speed, may be more appropriate for testing gait impairments related to chronic ankle instability.

Muscle activation patterns during backward walking in people with chronic ankle instability.

BACKGROUND: Altered walking patterns are often described in individuals with chronic ankle instability (CAI). Contemporary treatment paradigms recommend backward walking (BW) to improve locomotion in people with musculoskeletal disorders. The purpose of this study was to determine whether muscle activity and activation variability during BW differs between subjects with and without CAI. METHODS: Sixteen participants with CAI and 16 healthy controls walked on a treadmill at their self-selected speed under BW and forward walking (FW) conditions. Surface electromyography (EMG) data for the peroneus longus, tibialis anterior, medial gastrocnemius and gluteus medius muscles were collected. EMG amplitude normalized to maximum voluntary isometric contraction (%MVIC) and the standard deviation (SD) of the %MVIC EMG amplitude was calculated throughout the gait cycle. In addition, the area under the curve (AUC) of the %MVIC EMG amplitude was calculated before and after initial contact (pre-IC: 90-100% of stride; post-IC: 0-10% of stride). RESULTS: No differences between groups were noted in the %MVIC amplitude or activation variability (SD of %MVIC EMG) under BW or FW. In both groups, decreased tibialis anterior (p < 0.001) and gluteus medius (p = 0.01), and increased medial gastrocnemius (p < 0.001) activation were observed during pre- and post-IC under BW condition. CONCLUSION: Participants with CAI and healthy controls have similar muscle activity patterns during BW. Yet, the results should be interpreted with caution due to the heterogeneity of the CAI population.

The effectiveness of backward walking as a treatment for people with gait impairments: a systematic review and meta-analysis.

OBJECTIVE:: To investigate the effectiveness of backward walking in the treatment of people with gait impairments related to neurological and musculoskeletal disorders. DESIGN:: Systematic review and meta-analysis of randomized and quasi-randomized control studies. DATA SOURCES:: Searched from the date of inception to March 2018, and included PubMed, Scopus, Cochrane Library, PEDro, CINAHL, and the MEDLINE databases. METHODS:: Investigating the effects of backward walking on pain, functional disability, muscle strength, gait parameters, balance, stability, and plantar pressure in people with gait impairments. The PEDro scale was used to assess the quality. Similar outcomes were pooled by calculating the standardized mean difference. RESULTS:: Of the 21 studies (neurological 11 and musculoskeletal 10), 635 participants were included. The average PEDro score was 5.4/10. The meta-analysis demonstrated significant standardized mean difference values in favour of backward walking, with conventional physiotherapy treatment for two to four weeks to reduce pain (-0.87) and functional disability (-1.19) and to improve quadriceps strength (1.22) in patients suffering from knee osteoarthritis. The balance and stability in cases of juvenile rheumatoid arthritis, and gait parameters and muscle strength in anterior cruciate ligament injury improved significantly when backward walking was included as an exercise. There was no significant evidence in favour of backward walking in any of the other conditions. CONCLUSION:: The systematic review and meta-analysis suggests that backward walking with conventional physiotherapy treatment is effective and clinically worthwhile in patients with knee osteoarthritis. Insufficient evidence was available for the remaining gait impairment conditions and no conclusions could be drawn.