Verification of biomechanical factors of gait related to medial knee loading in patients 6 Months after total knee arthroplasty.

Background: The knee adduction moment (KAM) is considered an index for estimating the knee mechanical load, and increased KAM peak and KAM impulse are related to increased medial knee load and progression of knee joint degeneration. We aimed to verify the biomechanical factors of gait related to medial knee loading in patients 6 months after TKA. Methods: Thirty-nine women who underwent TKA were enrolled. A three-dimensional gait analysis was performed 6 months postoperatively to generate data on the lower limb joint angle, moment, and power at the backward component (braking phase) and forward component (propulsion phase) peaks of the ground reaction force. Medial knee loading was evaluated using the time-integrated value of KAM during the stance period (KAM impulse). The higher the value of the KAM impulse, the higher the medial knee joint load. The relationships between the KAM impulse and the data for biomechanical factors were evaluated using partial correlation analysis with gait speed as a control factor. Results: In the braking phase, the KAM impulse positively correlated with the knee adduction angle (r = 0.377) and negatively correlated with the toe-out angle (r = -0.355). The KAM impulse positively correlated with the knee adduction angle (r = 0.402), the hip flexion moment (r = 0.335), and the hip adduction moment (r = 0.565) and negatively correlated with the toe-out angle (r = -0.357) in the propulsive phase. Conclusion: The KAM impulse 6 months after TKA was related to the knee adduction angle, hip flexion moment, hip adduction moment, and toe-out angle. These findings may provide fundamental data for controlling variable medial knee joint load after TKA and implementing patient management strategies to ensure implant durability.

Early postoperative relationship between patient-reported outcome measures and gait biomechanical factors after total hip arthroplasty.

BACKGROUND: Patient-reported outcome measures (PROMs) have recently been considered as indicating clinical outcomes after total hip arthroplasty (THA). Although various factors are reportedly associated with post-THA and PROMs, the relationship with gait parameters, which are objective assessment factors after THA, remains unclear. RESEARCH QUESTION: What is the relationship between PROMs and gait biomechanical factors four weeks after THA? METHODS: Forty-five patients (six men and 39 women) who underwent THA were included. Three-dimensional gait analysis was performed four weeks post-THA; joint angle, internal moment, and power of the lower extremity at the first and second peaks of the vertical component of the floor reaction force were assessed for the operated side. PROMs were evaluated using the Japanese Orthopedic Association Hip Disease Evaluation Questionnaire (JHEQ). The relationship between the JHEQ score and extracted gait parameters was analyzed using gender and gait speed as control factors. RESULTS: For the JHEQ sub-domain, movement was positively correlated with the internal knee extension moment values at the first peak (r = 0.347). There was no significant correlation between JHEQ and the internal hip abduction moment value at the first peak. Mental status was negatively correlated with the hip flexion angle value at the second peak (r = -0.373), and positively correlated with the hip flexion moment value (r = 0.348). Total JHEQ scores and mental status were negatively correlated with the power of hip flexion value at the second peaks, respectively (r = -0.316, -0.444). SIGNIFICANCE: The results of this study may provide recovery guidelines to be used as an index for gait assessment in the early post-THA period. Further studies are needed to verify whether gait parameters can improve PROMs in the early post-THA period.

Relationships between early postoperative gait biomechanical factors and patient-reported outcome measures 6 months after total knee arthroplasty.

BACKGROUND: This study was focused on the gait parameters of the knee extensor and hip abductor muscle groups, which are believed to contribute to knee joint function improvement in early postoperative TKA. The associations between patient-reported outcome measures (PROMs) 6 months after total knee arthroplasty (TKA) and the early postoperative internal knee extension moment, knee extension negative joint power, and internal hip abduction moment while walking were investigated. METHODS: Twenty-one patients who underwent primary TKA for knee osteoarthritis were included. Three weeks after TKA, gait at a comfortable speed was measured by three-dimensional motion analysis. The lower limb joint angle, internal joint moment, and joint power parameters on the operated side while standing were calculated. The PROMs 6 months after TKA were assessed using the Japanese Knee Osteoarthritis Measure (JKOM). The relationship between each gait biomechanical parameter and the JKOM was determined. RESULTS: The maximum internal knee extension moment and maximum knee extension negative joint power during the early stance showed moderate negative correlations with the JKOM scores. The maximum internal hip abduction moment was not correlated with the JKOM scores. The maximum internal hip extension moment during the early stance and internal hip flexion moment during the late stance showed moderate negative correlations with the total JKOM scores. CONCLUSION: The early postoperative internal knee extension moment, maximum knee extension negative joint power, and internal hip extension and flexion moment are associated with patient PROMs 6 months after TKA.

Changes in the brain activation balance in motor-related areas after constraint-induced movement therapy; a longitudinal fMRI study.

PRIMARY OBJECTIVE: This study investigated the longitudinal changes in brain activation balance in motor-related areas after Constraint-Induced Movement Therapy (CIMT). METHODS AND PROCEDURES: The subjects included seven ischemic stroke patients with mild right hemiparesis. Eight normal subjects were also included. The patients underwent functional MRI and motor function tests (Fugl-Meyer Assessment; FMA, modified Wolf Motor Function Test; mWMFT) both before and immediately after CIMT and also after a 3-month follow-up. RESULTS: The motor function test scores improved immediately after CIMT; moreover, these scores were either maintained or improved even at the 3-month follow-up. In a comparison of the chronological data of the contralaterality index of the affected hand movement, the cerebellar activity changed significantly to ipsilateral activation immediately after CIMT and thereafter the cerebellar activity further changed to ipsilateral activation at the 3-month follow-up. A correlation was observed among the contralateral activation, FMA and mWMFT scores in SM1 and the ipsilateral activation and in the mWMFT scores in the cerebellum at the 3-month follow-up examinations. CONCLUSION: The participation of the contralateral SM1 and the ipsilateral cerebellum is thus considered to play an important role in the satisfactory recovery of the motor function after CIMT intervention.