Hsiao-Ching Yen

Bilateral knee osteoarthritis does not affect inter-joint coordination in older adults with gait deviations during obstacle-crossing.

Fifteen elderly subjects with bilateral medial knee osteoarthritis (OA) and 15 healthy elderly subjects walked and crossed obstacles with heights of 10%, 20%, and 30% of their leg lengths while sagittal angles and angular velocities of each joint were measured and their phase angles (phi) calculated. Continuous relative phase (CRP) were also obtained, i.e., phi(hip-knee) and phi(knee-ankle). The standard deviations of the CRP curve points were averaged to obtain deviation phase (DP) values for the stance and swing phases. Significant differences between the OA and control groups were found in several of the peak and crossing angles, and angular velocities at the knee and ankle. Both groups had similar CRP patterns, and the DP values of the hip-knee and knee-ankle CRP curves were not significantly different between the two groups. Despite significant changes in the joint kinematics, knee OA did not significantly change the way the motions of the lower limb joints are coordinated during obstacle-crossing. It appears that the OA groups adopted a particular biomechanical strategy among all possible strategies that can accommodate the OA-induced changes of the knee mechanics using unaltered inter-joint coordination control. This enabled the OA subjects to accommodate reliably the mechanical demands related to bilateral knee OA in the sagittal plane during obstacle-crossing. Maintaining normal and reliable inter-joint coordination may be considered a goal of therapeutic intervention, and the patterns and variability of inter-joint coordination can be used for the evaluation of treatment effects.

Symmetrical kinematic changes in highly functioning older patients post-stroke during obstacle-crossing

With the advances in stroke care, the number of high-functioning patients after stroke is increasing. However, existing clinical tools may not be sensitive enough to identify the residual deficits in these patients. The current study aimed to investigate the control of the pelvis, and the joints and end-point of the lower limbs in high-functioning older patients post-stroke during obstacle-crossing using motion analysis techniques. Twenty-four high-functioning older patients following unilateral stroke and fifteen healthy controls walked and crossed obstacles of three different heights. End-point variables (leading toe-clearance and trailing toe-obstacle distance) and crossing pelvic and joint angles were obtained for both limbs during leading limb crossing. Whether leading with the contralesional or ipsilesional limb, the stroke group exhibited significantly different joint kinematics from the controls mainly in the frontal and transverse planes, with greater leading toe-clearance, trailing toe-obstacle distance, and posterior pelvic tilt. None of the end-point and joint variables were significantly different between limbs. High-functioning patients post-stroke appeared to have acquired a specific symmetric kinematic strategy with increased leading toe-clearance during obstacle-crossing, most likely in order to prevent tripping. This symmetric strategy, possibly a consequence of brain reorganization, may help in performing functional activities during which symmetric performance between the contralesional and ipsilesional sides is required. Obstacle-crossing training with both limbs leading alternately may be helpful for the development of this symmetric strategy. It is suggested that computerized motion analysis of obstacle-crossing can be a sensitive assessment tool for distinguishing the motor performance between normal and high-functioning patients post-stroke.

Comparison of the Benefits between the Application of Transcutaneous Nerve Stimulation (TENS) and Functional Electrical Stimulation (FES) on the Postural Control and Mobility Ability in Acute Stroke Patients

Background and Purpose: Rehabilitation is recommended to start as early as possible after stroke onset. In the intensive care unit (ICU) of our facility, patients are generally prescribed bed rest within 3 days after stroke to reduce neurological complications. Additionally, the patients in stroke ICU may not have sufficient endurance, such as attention or alertness, for standard rehabilitation treatment. One potential rehabilitation approach for facilitation in stroke patients staying in ICU is electrical stimulation, such as transcutaneous nerve stimulation (TENS) and functional electrical stimulation (FES). Although some investigators have studied the benefits of FES in the early phase of recovery after stroke, limited studies have investigated the effects of TENS for motor recovery in stroke patients staying in stroke ICU. This study aims to investigate if TENS has similar effect on motor recovery as those who received FES. Methods: Forty-five stroke patients who were admitted in stroke ICU within 3 days after stroke onset were randomly allocated to standard rehabilitation (SR) group (n = 19), FES group (n = 13) and TENS group (n = 13). For the FES and TENS group, the interventions were applied at the tibialis anterior and quadriceps muscles over the paretic side for 30 min additional to standard rehabilitation. The measurements included whether the participants achieve three mobility milestones, which are sitting ≥ 5 mins, standing ≥ 1 min, and walking ≥ 50 m, within 14 days after stroke. We also measured the postural assessment scale for stroke patients (PASS) scores at the 2nd and 4th post-stroke weeks. Outcome measurements were analyzed with repeated measure analysis of variance and a χ2 test. Results: The rate of achieving the milestone of walking ≥ 50 m within 14 days after stroke in the FES and TENS groups were significantly higher than the SR group. The FES and TENS groups demonstrated significantly greater increase in the PASS scores at the 2nd post-stroke week than the SR group, but no significant differences were found between the FES and TENS groups. Conclusion and Clinical Relevance: Applying either TENS or FES on the paretic lower limb in stroke ICU improves the mobility and postural control in the acute stage. TENS and FES show similar effects on motor recovery in the acute phase.

Reliability of lower extremity muscle strength measurements with handheld dynamometry in stroke patients during the acute phase: a pilot reliability study

[Purpose] No literature has described a suitable method for measuring muscle strength in a supine position during acute phase after stroke. This study investigated the feasibility and reliability of using a commercial handheld dynamometer to measure the muscle strengths of the hip flexor, knee extensor, and dorsiflexor in the supine position with a modified method for patients at a stroke intensive care center within 7 days of stroke onset. [Subjects and Methods] Fifteen persons with acute stroke participated in this cross-sectional study. For each patient, the muscle strengths of the hip flexors, knee extensors, and dorsiflexors were measured twice by two testers on the same day. Each patient was re-tested at the same time of day one day later. Inter-rater and test-retest reliability were then determined by the intraclass correlation coefficients (ICCs). [Results] For the three muscle groups, the inter-rater reliability ICCs were all 0.99 and the test-retest reliability ICCs were greater than 0.85. The investigated method thus has good inter-rater reliability and high agreement between the test-retest measurements, with acceptable measurement errors. [Conclusion] The modified method using a handheld dynamometer to test the muscle strength of acute stroke patients is a feasible and reliable method for clinical use.