Sit-to-stand ability following ankle joint mobilizations in patients with hemiplegia

Introduction. People with central nervous system pathology frequently demonstrate ankle contractures that interfere with function. The purpose of this study was to determine if ankle joint mobilizations increased passive ankle mobility and improved sit-to-stand function in five patients with hemiplegia following a stroke. Methods. Data collection occurred over 13–15 sessions using a single-subject ABA design. Baseline measurements were collected in the first 3–6 sessions, followed by intervention and measurement sessions and one follow-up measurement session that occurred two weeks later. During each session, eight sit-to-stand measurement trials were performed. Ankle range of motion, kinematic data, and time to complete the task were measured using an electromagnetic tracking system (Flock of Birds®) and motion analysis software (MotionMonitor™). The intervention consisted of joint mobilizations to increase ankle dorsiflexion, performed on the hemiplegic lower leg at the proximal/distal tibia-fibula and talocrural articulations. Data analysis. Ankle mobility data and time to complete the sit-to-stand task were graphed for visual and statistical comparison. The C Statistic was used to identify the presence of a trend in the baseline data compared to the intervention data. Ankle kinematics were analyzed qualitatively to provide a description of the movement strategy. Results. Joint mobilizations increased passive ankle ROM in all five subjects, with statistically significant changes as determined by C statistic analysis. These improvements were maintained in the two week follow-up session. No significant trends were found for peak-to-peak ankle excursion during sit-to-stand, and a gradual decrease in time for sit-to-stand was noted during both baseline and intervention sessions. Analysis of ankle kinematics revealed varying patterns of change for the individual subjects. Conclusion. Although joint mobilizations were effective at improving ankle mobility in five subjects with hemiplegia, these improvements did not appear to directly affect sit-to-stand function. The subjects did seem to benefit from practicing this functional task as part of the repeated measure design, as demonstrated by a gradual decrease in time to perform sit-to-stand and improved consistency in ankle kinematics. One recommendation for future research is to incorporate additional interventions to specifically encourage the patient to use their increased ankle mobility during functional tasks.