Effects of a Squatting With Hip Adduction in Patients With Patellofemoral Pain Syndrome

Not Applicable

Completed

• Conditions: PFPS

• Registration Number: NCT06681961
• Lead Sponsor: China Medical University Hospital

Brief Summary

An imbalance in the activation and onset time of the vastus medialis oblique (VMO) and vastus lateralis (VL) muscles may be one of the primary causes of PFPS. Several studies have discussed various exercise methods believed to selectively contract the (VMO) muscle for treating patellofemoral pain syndrome. VMO activity is higher during static closed-chain tasks combined with hip adduction, indicating that performing hip adduction exercises may selectively strengthen the VMO muscle.

Detailed Description

Patellofemoral pain syndrome (PFPS) poses challenges in motor control and pain management, especially regarding balanced muscle activation of the vastus medialis oblique (VMO) and vastus lateralis (VL). This study introduces a home-based PFPS rehabilitation approach involving a squat exercise program with hip adduction, examining its effects on motor control and clinical outcomes. Thirty PFPS participants were randomly assigned to conventional squatting (SQU) or squatting with hip adduction (SQU-HA) groups. Participants performed exercises five days a week for 8 weeks, with pre- and post-assessments capturing clinical measures and motor control indicators using electromyography (EMG). This home-based program, integrating hip adduction into squats, enhances motor control, reduces knee stress, and improves daily function, ensuring continued care post-pandemic.

Study Timeline

• Study Start: 2017-11-27
• Primary Completion: 2018-11-30
• Study Completion: 2019-01-05
• Status Verified: 2024-11
• Study First Submitted: 2024-11-04
• Study First Submitted QC: 2024-11-07
• Last Update Submitted: 2024-11-07
• Study First Posted: 2024-11-11
• Last Update Posted: 2024-11-11

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 30

Inclusion Criteria

• Age 20-50 years.
• Pain around the patella at least two of the following activities¬-standing up after prolonged sitting, going up and down the stairs, running, jumping, squatting, kneeling, and high-angle knee flexion for a long time.
• Knee joint pain for ≥3 months.
• Pain level of ≥ 30 mm on a 100-mm visual analog scale (VAS).

Exclusion Criteria

• Had a history of patellar subluxation, dislocation, or knee surgery.
• Had central or peripheral neurological pathology.
• Had an obvious knee joint deformity or lower extremity malalignment.
• Experienced severe knee joint pain (VAS) score > 80 mm), or received nonsteroidal anti-inflammatory drugs, injections, or physical therapy within the past 3 months.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
VMO/VL ratio	pre-intervention and after 8-week intervention	represents the amplitude ratio of VMO relative to VL.
Onset time (unit: msec)	pre-intervention and after 8-week intervention	at 200 ms before the beginning of the trial, as the baseline, the onset of EMG activation was identified as the point at which the EMG amplitude was more than three standard deviations from the baseline level for at least 25 ms.
VMO - VL (unit: msec)	pre-intervention and after 8-week intervention	represented the onset time differences of VMO relative to VL, with a positive (negative) value indicating a delayed (early) onset time of VMO relative to VL.
Q angle (unit: degree)	pre-intervention and after 8-week intervention	The angle was calculated with the intersection formed by two lines crossing the center of the patella. The first line went from the ASIS to the center of the patella and the second from the anterior tuberosity of the tibia to the center of the patella.
The visual analogue scale (VAS) (unit: mm)	pre-intervention and after 8-week intervention	VAS was used to assess pain severity. The participants were asked to mark their pain levels on a 100-mm ruler (ranging from 0 = "no pain" to 100 = "unbearable pain") before and after the exercise program.
patellofemoral pain severity scale (PSS) (unit: score)	pre-intervention and after 8-week intervention	PSS was used to measure PFPS associated with functional activities over the past week. The scale comprises 10 items, including climbing/descending stairs, squatting, walking, jogging, running/sprinting, participating in a sport, sitting with knees bent (for 20 min), kneeling, resting, and following an activity. The maximum score was 100 points. The participants rated their pain on a 100-mm VAS, ranging from 0 = "no pain" to 100 = "unbearable pain".
Amplitudes of muscle activation (unit: %MVC)	pre-intervention and after 8-week intervention	represented the mean RMSs for each muscle which was normalized by the maximal voluntary contractions (MVC).

Trial Locations

Locations (1)

China Medical University; 🇨🇳 Taichung, Taiwan