BACKGROUND: Extensor training improves the quadriceps contraction intensity of knee osteoarthritis. But the duration of effects is limited. This study aimed to assess whether electroacupuncture (EA) with extensor training (EA + E) has better short-and long-term effects than simple extensor training (E). METHODS: Fifty-four patients were categorized into EA + E and E groups. Elastic shear wave imaging was employed to ascertain the quadriceps elastic modulus values (EMV) at different time points and extension angles. WOMAC scale was used to measure knee function. RESULTS: Compared to before EA, the vastus lateralis (VL) EMV with 180° knee extension immediately after EA increased significantly. After 1 month, the vastus medialis (VM) EMV with 180° extension increased and WOMAC scores decreased significantly than immediately after EA. The EMV of the VM and VL of group EA + E increased, and WOMAC scores decreased significantly compared to group E after 1 month. After 6 months, EMV of the VM and VL in EA + E group significantly increased, and WOMAC scores significantly decreased compared to E group. CONCLUSIONS: In short- and long-term, EA with extensor training enhances the contraction strength of the quadriceps and knee function for OA. TRIAL REGISTRATION: This prospective single-center randomized controlled trial was approved by the Review Committee of the First Affiliated Hospital of Sun Yat-sen University (Registration date: 28/02/2023, Ethical Number: [2023] 005
The Clinical trial registration number: ChiCTR2300076651. KEY POINTS: • The contraction strength of the quadriceps femoris muscle in OA was detected with shear wave elastic ultrasound, and electroacupuncture immediately enhanced the contraction strength. • After the completion of electroacupuncture treatment, the quadriceps strength and the function of knee joint in OA can be continuously improved, which will last for 6 months. • In short and long term, electroacupuncture with extensor training has better enhancement of quadriceps contraction strength of and knee function for OA than extention only.