Effects of Clamshell Exercises in Addition to Standardized Physical Therapy in the Management of Patellofemoral Pain Syndrome. A Randomized Controlled Trial
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 40
- 试验地点
- 1
- 主要终点
- Change in Pain Intensity Measured by the Numeric Pain Rating Scale (NPRS)
研究概览
简要总结
This randomized controlled trial aims to evaluate whether adding clamshell exercises to standardized physical therapy provides greater improvements in pain and knee function than standardized physical therapy alone in individuals with patellofemoral pain syndrome (PFPS). PFPS is a common musculoskeletal condition characterized by pain around or behind the kneecap that is aggravated by activities such as stair climbing, squatting, running, and prolonged sitting.
Participants aged 18-45 years with clinically diagnosed PFPS will be randomly assigned to one of two groups. The control group will receive standardized physical therapy consisting of warm-up exercises, stretching, quadriceps and lower-limb strengthening exercises, and cool-down activities. The experimental group will receive the same standardized physical therapy program with the addition of clamshell exercises targeting the gluteus medius and hip external rotator muscles.
Both groups will participate in supervised treatment sessions lasting approximately 45 minutes, three times per week, for four weeks. Pain intensity will be measured using the Numeric Pain Rating Scale (NPRS), and knee function will be assessed using the Kujala Anterior Knee Pain Scale before and after the intervention. The findings of this study may help determine whether incorporating clamshell exercises into routine physiotherapy improves rehabilitation outcomes for patients with PFPS.
详细描述
Patellofemoral pain syndrome (PFPS) is one of the most common causes of anterior knee pain, affecting both physically active individuals and the general population. The condition is associated with pain during activities that increase patellofemoral joint loading, including squatting, stair climbing, running, jumping, and prolonged sitting. Altered lower-limb biomechanics, particularly weakness of the hip abductors and external rotators, may contribute to excessive femoral internal rotation and dynamic knee valgus, thereby increasing patellofemoral joint stress.
Conventional physiotherapy for PFPS typically includes stretching, quadriceps strengthening, and functional rehabilitation. Although these interventions are beneficial, many patients continue to experience persistent symptoms or recurrence. Recent evidence suggests that strengthening the hip musculature, particularly the gluteus medius, may improve lower-limb alignment and reduce patellofemoral joint stress. The clamshell exercise is a simple, low-cost exercise designed to activate the hip abductors and external rotators and may provide additional clinical benefit when combined with standard physiotherapy.
The purpose of this randomized controlled trial is to determine whether adding clamshell exercises to standardized physical therapy results in greater reductions in pain and improvements in knee function compared with standardized physical therapy alone in patients with PFPS.
Participants aged 18-45 years who meet the American Physical Therapy Association clinical diagnostic criteria for PFPS and have symptoms lasting at least three months with a pain score of 3 or higher on the Numeric Pain Rating Scale (NPRS) will be recruited. Participants with previous knee surgery, significant ligament or meniscal injuries, patellar dislocation, osteoarthritis, lumbar radiculopathy, hip pathology, systemic inflammatory arthritis, recent corticosteroid injection or surgery, neuromuscular disorders, pregnancy, or other exclusion criteria will not be eligible.
Approximately 40 participants will be enrolled using purposive sampling after accounting for potential loss to follow-up. Participants will be randomly allocated into one of two treatment groups:
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Single (Outcomes Assessor)
盲法说明
This is a single-blind randomized controlled trial. The outcome assessor will be blinded to treatment allocation to minimize assessment bias. Due to the nature of the exercise interventions, the treating physiotherapist cannot be blinded. Participants will not be informed of the study hypothesis or comparative purpose of the interventions, although complete blinding of participants is not feasible.
入排标准
- 年龄范围
- 18 Years 至 45 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Adults aged 18 to 45 years. Male or female participants. Clinically diagnosed with patellofemoral pain syndrome (PFPS) according to the American Physical Therapy Association (APTA) clinical practice guidelines.
- •Presence of retropatellar or peripatellar pain. Reproduction of retropatellar or peripatellar pain during squatting or other functional activities that load the patellofemoral joint in knee flexion.
- •Symptoms present for at least 3 months. Pain intensity of ≥3 on the Numeric Pain Rating Scale (NPRS) during aggravating activities.
- •Able and willing to provide written informed consent and comply with the study procedures.
排除标准
- •History of knee surgery, ligament injury, meniscal tear, patellar dislocation, or knee osteoarthritis.
- •Lumbar radiculopathy, hip pathology, or systemic inflammatory arthritis (e.g., rheumatoid arthritis).
- •Corticosteroid injection or knee surgery within the previous 3 months. Neuromuscular disorders affecting muscle function (e.g., stroke or Parkinson's disease).
- •Pregnancy or within 6 months postpartum. Family history of early degenerative joint disease. Any condition that, in the investigator's opinion, would interfere with safe participation or completion of the study.
结局指标
主要结局
Change in Pain Intensity Measured by the Numeric Pain Rating Scale (NPRS)
时间窗: Baseline and Week 4 (end of intervention)
Pain intensity will be assessed using the 11-point Numeric Pain Rating Scale (NPRS), where 0 indicates no pain and 10 indicates the worst imaginable pain. The primary outcome is the change in NPRS score from baseline to the end of the intervention.
次要结局
- Change in Knee Function Measured by the Kujala Anterior Knee Pain Scale(Baseline and Week 4 (end of intervention))