Quadriceps Strengthening At Different Angles in Patellofemoral Pain

Official title

Quadriceps Strengthening Under Limited Range of Motion Compared to Patient-guided Range of Motion on Pain, Kinesiophobia and Function in Individuals with Patellofemoral Pain: a Randomized Clinical Trial

Overview

Introduction: Patellofemoral pain (PFP) is characterized by anterior, retropatellar and/or peripatellar pain during activities such as running, squatting, kneeling, or prolonged sitting. This condition affects approximately 25% of the general population. Given its complex and multifactorial etiology, PFP presents a significant treatment challenge. All clinical practice guidelines recommend strengthening the quadriceps femoris muscle as a key component in the management of PFP. However, exercises aimed at strengthening the quadriceps place considerable stress on the patellofemoral joint and are often poorly tolerated by patients. Clinicians commonly employ a conservative strategy that restricts open kinetic chain knee extension exercises to a limited range of 90° to 45° of knee flexion and closed kinetic chain exercises to 0° to 45°. Yet, restricting the range of motion may result in suboptimal outcomes for patients with higher load tolerance and may foster beliefs regarding knee joint fragility. Objective: We aim to compare the effects of quadriceps femoris strengthening within a limited range to a patient-guided range of motion on pain, function, knee confidence, and kinesiophobia in individuals with PFP. Methods: A randomized clinical trial will be conducted with two parallel groups, using a balanced 1:1 allocation and a double-blind design. The study population will include men and women aged 18 to 35 years, diagnosed with PFP. Participants will be randomly assigned to either the limited range group or the patient-guided range of motion group. They will participate in a supervised therapeutic protocol, with sessions averaging 40 minutes, twice a week, for six consecutive weeks. The primary outcome will be pain, assessed using the numerical pain rating scale (0-10), and kinesiophobia, assessed by the Tampa Scale . Secondary outcomes will include pain, self-reported function, measured by the Anterior Knee Pain Scale (AKPS), perceived improvement by the Global Rating of Change Scale, quadriceps strength, kinesiophobia and analgesic consumption.

Detailed description

Participants with patellofemoral pain will be randomized into two intervention groups. All participants will start with a warm-up on a stationary bike, followed by dynamic stretching exercises targeting the quadriceps, hamstrings, calf muscles, adductors, and abductors.

Open kinetic chain exercises will be performed using a leg extension machine, while closed kinetic chain exercises will include free squats and Bulgarian squats.

The Limited-RoM Quadriceps Strengthening group will perform open-kinetic-chain quadriceps strengthening exercises within a range of 90° to 45° of knee flexion and closed-kinetic-chain within a range of 0° to 45°.

The Patient-Guided-RoM Quadriceps Strengthening group will perform quadriceps strengthening exercises in both open and closed kinetic chains to the maximum tolerated by the patient based on their symptoms. The patient-guided maximum range of motion will be adjusted based on pain intensity, comfort, and patient response, following a shared decision-making approach with a clinician. The goal will be to maintain exercises at the greatest possible range of motion.

The identification of the patient-guided angle in both open and closed kinetic chain exercises will be determined as follows: the patient will perform 10 maximum repetitions on the leg with PFP, prioritizing range of motion over load. During the execution, the range of motion and load will be guided by the numerical pain rating scale and the perceived exertion scale.

Participants will complete 12 sessions, twice a week, supervised by a physiotherapist. Assessments will be conducted at baseline, six weeks, and six months, evaluating pain, function, kinesiophobia, crepitus, perception of effect, and weekly pain-killer consumption.

Interventions

• Other Protected Range Quadriceps Strengthening group
  Warm-up: Start with 5 minutes of stationary biking. Then, proceed with two sets of 30-second dynamic stretches targeting the quadriceps, hamstrings, calf muscles, and adductors, followed by static stretching for the abductors. Strengthening: Complete 3 sets of 8-12 repetitions for each exercise, aiming for a perceived effort level on the Borg scale between 60% and 80%. Increase the load by 2%-10% when the patient can perform 14 or more repetitions in the final set while maintaining the Borg sca
• Other Patient-Guided Range Quadriceps Strengthening group
  Warm-up: 5 minutes of stationary biking. Next, perform two sets of 30-second stretches for the quadriceps, hamstrings, calf muscles, adductors and abductors hip. Strengthening: Patients will complete 3 sets of 8 to 12 repetitions for each exercise, aiming for a perceived effort level of 60% to 80% on the Borg scale. Load will be increased by 2% to 10% when patients can complete 14 or more repetitions in the final set while maintaining the Borg scale between 60% and 80%. Quadriceps strengthenin

Primary outcome measures

• Knee pain intensity [Time frame: Knee pain intensity measured by the NPRS after six-week intervention.]
• Kinesiophobia [Time frame: Kinesiophobia assessed by the Tampa Scale of Kinesiophobia after six-week intervention.]

Secondary outcome measures (7)

• Perception of effect [Time frame: Global Rating of Change Scale after six-week intervention and six-month follow-up.]
• Knee crepitus [Time frame: Crepitus during knee extension after six-week intervention.]
• Weekly analgesic consumption [Time frame: Weekly, throughout the six-week intervention period.]
• Knee pain intensity [Time frame: Knee pain intensity measured by the NPRS at six-month follow-up.]
• Knee function [Time frame: Self-reported function measured by the AKPS at six-week and six-month follow-up.]
• Kinesiophobia [Time frame: Kinesiophobia assessed by the Tampa Scale of Kinesiophobia six-month follow-up.]
• Quadriceps peak torque [Time frame: Quadriceps strength measured by the isokinetic dynamometer after six-week intervention.]

Eligibility criteria

Inclusion criteria

• Individuals aged between 18 and 35 years.
• Diagnosis of patellofemoral pain characterized by peri- or retropatellar pain.
• Pain reproduced in at least two of the following activities: ascending or descending stairs, squatting, kneeling, prolonged sitting, jumping, running, or palpation of the medial and/or lateral facets of the patella.
• Insidious onset of symptoms.
• Symptoms duration of at least three months.
• Minimum score of three on the numerical pain rating scale (NPRS) in the past week.
• Maximum score of 86 points on the Anterior Knee Pain Scale (AKPS)
• In cases of bilateral pain, the more symptomatic knee will be included.

Exclusion criteria

• History of surgery and/or fractures in the lower limb joints.
• Other knee joint-related injuries such as meniscal tears, ligament injuries.
• History of patellar subluxation or dislocation.
• Signs of osteoarthritis.
• Patellar and quadriceps tendinopathy.
• Osgood-Schlatter syndrome.
• Presence of knee joint edema.
• Contraindications to resistance exercises informed by a physician.
• Corticosteroid injection within the last 6 months.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Double blind

Primary purpose

Treatment

Study locations

Brazil · 1 center

• Physiotherapy Department, Federal University of Ceará — Fortaleza

Publications

• Almeida GPL, Rodrigues HLDN, Coelho BAL, Rodrigues CAS, Lima POP. Anteromedial versus posterolateral hip musculature strengthening with dose-controlled in women with patellofemoral pain: A randomized controlled trial. Phys Ther Sport. 2021 May;49:149-156. doi: 10.1016/j.ptsp.2021.02.016. Epub 2021 Mar 2. PMID 33689989
• Collins NJ, Bierma-Zeinstra SM, Crossley KM, van Linschoten RL, Vicenzino B, van Middelkoop M. Prognostic factors for patellofemoral pain: a multicentre observational analysis. Br J Sports Med. 2013 Mar;47(4):227-33. doi: 10.1136/bjsports-2012-091696. Epub 2012 Dec 13. PMID 23242955
• Collins NJ, Barton CJ, van Middelkoop M, Callaghan MJ, Rathleff MS, Vicenzino BT, Davis IS, Powers CM, Macri EM, Hart HF, de Oliveira Silva D, Crossley KM. 2018 Consensus statement on exercise therapy and physical interventions (orthoses, taping and manual therapy) to treat patellofemoral pain: recommendations from the 5th International Patellofemoral Pain Research Retreat, Gold Coast, Australia, PMID 29925502
• Crossley KM, Bennell KL, Cowan SM, Green S. Analysis of outcome measures for persons with patellofemoral pain: which are reliable and valid? Arch Phys Med Rehabil. 2004 May;85(5):815-22. doi: 10.1016/s0003-9993(03)00613-0. PMID 15129407
• da Cunha RA, Costa LO, Hespanhol Junior LC, Pires RS, Kujala UM, Lopes AD. Translation, cross-cultural adaptation, and clinimetric testing of instruments used to assess patients with patellofemoral pain syndrome in the Brazilian population. J Orthop Sports Phys Ther. 2013 May;43(5):332-9. doi: 10.2519/jospt.2013.4228. Epub 2013 Mar 13. PMID 23485881
• Escamilla RF, Fleisig GS, Zheng N, Barrentine SW, Wilk KE, Andrews JR. Biomechanics of the knee during closed kinetic chain and open kinetic chain exercises. Med Sci Sports Exerc. 1998 Apr;30(4):556-69. doi: 10.1097/00005768-199804000-00014. PMID 9565938
• Gallasch CH, Alexandre NM. The measurement of musculoskeletal pain intensity: a comparison of four methods. Rev Gaucha Enferm. 2007 Jun;28(2):260-5. PMID 17907648
• Giles L, Webster KE, McClelland J, Cook JL. Quadriceps strengthening with and without blood flow restriction in the treatment of patellofemoral pain: a double-blind randomised trial. Br J Sports Med. 2017 Dec;51(23):1688-1694. doi: 10.1136/bjsports-2016-096329. Epub 2017 May 12. PMID 28500081

Identifiers

NCT: NCT06502795 · PFPKarine

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗