Clinical reasoning of ultrasound imaging-guided manual passive manipulation for adhesion prevention in a patient with total knee arthroplasty: a case report.

INTRODUCTION: Patients with total knee arthroplasty occasionally develop postoperative abnormalities such as posttraumatic knee stiffness and arthrofibrosis, which may affect activities of daily living. However, there are no clear assessment methods or interventions for knee stiffness. Musculoskeletal ultrasound imaging enables real-time evaluation of mobility and flexibility of tissues. The purpose of this case report was to describe the use of musculoskeletal ultrasound imaging for evaluating the optimal location and methods of passive manipulation. CASE DESCRIPTION: The patient was an 82-year-old woman who had undergone total knee arthroplasty. She was unable to climb stairs due to limited knee flexion. Based on the results of musculoskeletal ultrasound imaging assessment, we hypothesized that the knee flexion limitation was caused by decreased sliding movement of the suprapatellar pouch. Hence, we performed passive manipulation on the tissue with decreased sliding under musculoskeletal ultrasound guidance. OUTCOMES: The patient's knee flexion angle increased from 90° to 110° within 1 week of intervention, and her gait speed improved from 16.48 to 13.2 s per 10 m. Furthermore, after the intervention, she was able to climb 10 steps using a handrail. DISCUSSION: Ultrasound imaging is important because it allows the examination of tissues with mobility changes such as in arthrofibrosis. Our work highlights the use of musculoskeletal ultrasound imaging for identifying the target region for therapy and for providing guidance during passive manipulation.

Effect of Increased Flexor Hallucis Longus Muscle Activity on Ground Reaction Force during Landing.

Repeated high-impact ground forces can lead to injury and decreased performance. While increasing flexor hallucis longus (FHL) muscle activity is known to increase stiffness and elasticity, it is unknown if this also decreases ground reaction forces by shock absorption during landing. This study aimed to determine whether increasing FHL muscle activity affects ground reaction force during landing in healthy subjects. Eight subjects performed single-leg steps onto a force platform for five trials, with and without flexion of the metatarsophalangeal (MTP) joint at the moment of landing. Integrated surface electromyography (sEMG) of the FHL and medial gastrocnemius (MG) and ground reaction forces (GRFs) were measured. sEMG and GRF during the 50 ms before and 100 ms following initial ground contact were analyzed and compared. Flexion of the MTP joint condition significantly decreased the vertical and mediolateral force peaks of GRF, and FHL muscle activity increased. Flexion of the MTP joint at the moment of landing reduces GRF in healthy subjects through force dissipation in the foot, by increased FHL muscle activity. The results suggest that this may contribute to injury prevention by reducing the impact force through flexing the MTP joint at the moment of landing.

Immediate effects of plantar vibration stimuli during static upright posture following total hip arthroplasty in females.

PURPOSE: Proprioceptive function of the lower limbs deteriorates in patients following total hip arthroplasty. Patients show poor balance and rely more on visual information than proprioceptive information. Plantar vibration stimuli can mechanically enhance somatosensory input from the plantar cutaneous mechanoreceptors, thereby improving static balance. Plantar vibration stimuli may improve static balance in patients after total hip arthroplasty. This is the first study to investigate whether plantar vibration stimuli affects static balance during the early phase following total hip arthroplasty. MATERIALS AND METHODS: In this cross-over design study, 16 female patients (aged 65.1 ± 11.0 years) received plantar vibration stimuli for 2 minutes or the sham interventions after total hip arthroplasty in a randomized order on different days. The foot centre of pressure was measured for the total path length, mediolateral path length, and anteroposterior path length directions before and immediately after the interventions in the static standing position both with eyes open and closed. Patients were instructed to minimize body sway when standing. RESULTS: A significant increase was observed in the centre of pressure parameters in the eyes closed condition than in the eyes open condition. The centre of pressure parameters for the eyes closed condition was significantly decreased after vibration interventions than that before intervention. CONCLUSIONS: This study supports the view that plantar vibration stimuli can change static balance in patients in the early phase after total hip arthroplasty temporarily by up-weighting sensory information. These stimuli may serve as a treatment option for influencing balance following total hip arthroplasty.