Tokyo, Sept. 18 -- UMIN Clinical Trials Registry (UMIN-CTR) received information related to the study (UMIN000059103) titled 'Study on the Effects of Cryotherapy and Electrical Stimulation Rehabilitation after Total Knee Arthroplasty' on Sept. 18.

Study Type: Interventional

Study Design: Basic Design - Cross-over Randomization - Randomized Blinding - Open -no one is blinded Control - Active

Primary Sponsor: Institute - Social Medical Corporation Yahata Steel Memorial Hospital

Condition: Condition - Patients after total knee arthroplasty (TKA) Classification by malignancy - Others Genomic information - NO

Objective: Narrative objectives1 - To clarify whether cryotherapy administered prior to neuromuscular electrical stimulation (NMES) improves maximum tolerable current intensity (CT) and quadriceps strength in patients after total knee arthroplasty (TKA). Basic objectives2 - Others

Intervention: Interventions/Control_1 - Name: Cryotherapy + NMES Period / Number / Frequency: Performed once on postoperative days 7, 8, 14, and 15 (total of 4 sessions). Time window: 10:00-12:00 am on each assessment day.

Procedure:

Electrodes: Surface electrodes are placed on the quadriceps muscle.

Positioning / Fixation: The knee joint is fixed at 60 deg flexion using an isometric dynamometer (e.g., Cybex). The trunk and thigh are secured with straps, and the distal lower leg is fixed.

NMES settings: Frequency 50 Hz; pulse width 300 us.

Intensity setting (CT measurement): Before the intervention, NMES is applied. The current intensity is gradually increased, and the maximum tolerable current intensity (CT; mA) is recorded. Thereafter, knee extension strength (isometric torque) during NMES at the CT intensity is measured.

Cryotherapy: The anterior knee is cooled for approximately 10 min using an ice pack and elastic bandage. Immediately after cooling, skin temperature is measured with a non-contact thermometer to confirm the cooling effect.

Reassessment: After skin temperature measurement, CT is reassessed, and knee extension strength at the CT intensity is measured again. Three trials are performed with 1 min rest between each trial, and the highest value (normalized to body weight in Nm/kg if necessary) is adopted. Interventions/Control_2 - Name: NMES only (no cryotherapy) Period / Number / Frequency: Performed once on postoperative days 7, 8, 14, and 15 (total of 4 sessions). Time window: 10:00-12:00 am on each assessment day. No cryotherapy (ice pack or ice bag) is applied during this period. Procedure:

Electrodes: Surface electrodes are placed on the quadriceps muscle.

Positioning / Fixation: The knee joint is fixed at 60 deg flexion using an isometric dynamometer (e.g., Cybex). The trunk and thigh are secured with straps, and the distal lower leg is fixed.

NMES settings: Frequency 50 Hz; pulse width 300 us.

Intensity setting (CT measurement): The current intensity is gradually increased, and the maximum tolerable current intensity (CT; mA) is recorded at the point when the participant reports "no longer tolerable".

Strength measurement: At the CT intensity, the isometric knee extension torque generated at the NMES "ON" timing is automatically recorded. Three trials are performed with 1 minute rest intervals, and the highest value (normalized to body weight in Nm/kg if necessary) is adopted.

Eligibility: Age-lower limit - 60 years-old = Gender - Male and Female Key inclusion criteria - Patients scheduled to undergo unilateral total knee arthroplasty (TKA) at our hospital between September 2025 and March 2027

Male or female patients aged 60 to 90 years

Patients who were able to walk independently or with a T-cane prior to surgery

Patients who are in a clinically stable condition after surgery and judged to be able to safely undergo postoperative rehabilitation

Patients who understand the content of the study and provide written informed consent Key exclusion criteria - Patients who have undergone bilateral TKA or revision TKA

Patients with difficulty in understanding instructions due to cerebrovascular disease, neuromuscular disorders, or severe dementia

Patients with cardiac pacemakers or implantable cardioverter-defibrillators (contraindication for NMES)

Patients with skin disorders, surgical site infection, or severe swelling around the knee (making NMES or cryotherapy infeasible)

Patients who develop postoperative readmission or surgical complications (e.g., deep infection, venous thromboembolism)

Patients judged unable to continue physical therapy during the intervention period Target Size - 20

Recruitment Status: Recruitment status - Preinitiation Date of protocol fixation - 2025 Year 07 Month 29 Day Date of IRB - 2025 Year 08 Month 20 Day Anticipated trial start date - 2025 Year 09 Month 17 Day Last follow-up date - 2027 Year 03 Month 31 Day

To know more, visit https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000067587

Disclaimer: Curated by HT Syndication.