NCT07657481

Brief Summary

Knee osteoarthritis (OA) is one of the most common joint disorders worldwide and is a leading cause of pain, limited mobility, and functional disability, particularly in the elderly population. According to 2020 data, approximately 654 million individuals aged 40 years and older are affected by knee OA worldwide, with a global prevalence of 22.9% in this age group. In our country as well, OA is reported as the second most common rheumatologic disease. The disease not only negatively affects individuals' quality of life but also creates a significant socioeconomic burden through work loss, hospital admissions, and the need for surgical interventions. The pathogenesis of knee OA is a complex process involving articular cartilage degeneration, subchondral bone sclerosis, synovial tissue proliferation, and osteophyte formation. Once cartilage damage begins, its capacity for spontaneous healing is extremely limited; therefore, early interventions aimed at slowing or halting disease progression are of critical importance. In this context, non-pharmacological interventions, particularly exercise programs that may contribute to maintaining cartilage integrity, are strongly recommended as first-line treatment options in current clinical guidelines. The beneficial effects of exercise therapy on pain and function in patients with knee OA are well documented. However, the structural effects of exercise on femoral cartilage thickness have been relatively less investigated. Tuna et al. evaluated femoral cartilage thickness using ultrasonography in 40 patients with knee OA following a 12-week quadriceps strengthening program and reported statistically significant increases in cartilage thickness in the medial condyle, lateral condyle, and intercondylar region at 3 months. This pioneering study suggests that muscle strengthening programs may have not only symptomatic but also structural benefits. Similarly, Bozan et al. reported a strong positive correlation between quadriceps muscle thickness (rectus femoris + vastus intermedius) and femoral cartilage thickness, supporting the idea that muscle loss parallels cartilage degeneration. However, these studies focused exclusively on the quadriceps muscle, and the effects of hip musculature on femoral cartilage thickness have not been investigated. Recent biomechanical studies indicate that hip abductor and adductor muscles play a critical role in knee joint loading patterns. Hip abductor muscles provide pelvic stability during gait and directly influence knee adduction moments. Weakness of the gluteus medius leads to contralateral pelvic drop, increasing medial compartment loading on the ipsilateral knee and accelerating medial tibiofemoral cartilage wear. Indeed, Segal et al., using data from the Multicenter Osteoarthritis Study (MOST), demonstrated via MRI that greater hip abductor strength significantly reduces the risk of progression of medial patellofemoral and lateral tibiofemoral cartilage damage. On the other hand, hip adductor muscles are also thought to contribute to knee adduction moments by eccentrically controlling femoral varus motion; however, this relationship has been studied far less compared to quadriceps and abductors. Systematic reviews and meta-analyses have shown that individuals with knee OA have up to 24% lower isometric hip abductor strength compared to healthy controls. Randomized controlled trials investigating combined hip and quadriceps strengthening programs have reported significant improvements in pain and function. However, none of these studies have used femoral cartilage thickness measured by ultrasonography as a primary outcome. A review of the current literature reveals that although studies exist examining the effects of quadriceps strengthening on femoral cartilage thickness, no randomized controlled trial has compared hip abductor and adductor strengthening exercises with a quadriceps strengthening program, using ultrasonographic femoral cartilage thickness as the primary outcome measure. This study aims to address this gap. All interventions will be applied as non-invasive home exercise programs, and all measurements will be performed using ultrasonography. Baseline, 1-month, and 3-month assessments will also allow evaluation of the temporal effects of exercise on cartilage structure. The findings are expected to provide scientific evidence regarding the structural protective effects of hip exercises in knee OA rehabilitation and serve as pilot data for future large-scale multicenter studies. The aim of this study is to compare patients with knee OA receiving quadriceps strengthening exercises alone with those receiving additional hip abductor/adductor strengthening exercises in terms of changes in femoral cartilage thickness, and to evaluate whether there is a correlation between femoral cartilage thickness and the thickness of the rectus femoris, gluteus medius,

Trial Health

63
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
56

participants targeted

Target at P25-P50 for not_applicable

Timeline
11mo left

Started Aug 2026

Geographic Reach
1 country

1 active site

Status
not yet recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

June 14, 2026

Completed
4 days until next milestone

First Posted

Study publicly available on registry

June 18, 2026

Completed
2 months until next milestone

Study Start

First participant enrolled

August 20, 2026

Expected
7 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

April 1, 2027

3 months until next milestone

Study Completion

Last participant's last visit for all outcomes

July 1, 2027

Last Updated

June 22, 2026

Status Verified

June 1, 2026

Enrollment Period

7 months

First QC Date

June 14, 2026

Last Update Submit

June 17, 2026

Conditions

Keywords

knee osteoartritisfemoral cartilage thiknessquadriceps strengthening exerciseship abductor and adductor strengthening exercises

Outcome Measures

Primary Outcomes (1)

  • Medial femoral condyle cartilage thickness (mm)

    All ultrasonographic measurements will be performed using a Clarius L7 HD3 linear high-frequency transducer (7.5-12 MHz) with the knee positioned in 90° flexion in a standardized manner. Three measurements will be obtained at each anatomical location, and the mean value will be recorded for analysis.

    Participants receiving treatment will be evaluated at baseline (T0), at Month 1 (T1), and at Month 3 (T2).

Secondary Outcomes (9)

  • Lateral femoral condyle cartilage thickness (mm)

    Participants receiving treatment will be evaluated at baseline (T0), at Month 1 (T1), and at Month 3 (T2).

  • Intercondylar area cartilage thickness (mm)

    Participants receiving treatment will be evaluated at baseline (T0), at Month 1 (T1), and at Month 3 (T2).

  • Ultrasound Femoral Cartilage Degeneration Grade

    Participants receiving treatment will be evaluated at baseline (T0), at Month 1 (T1), and at Month 3 (T2).

  • Synovial Hypertrophy Grade

    Participants receiving treatment will be evaluated at baseline (T0), at Month 1 (T1), and at Month 3 (T2).

  • Rectus femoris muscle thickness (cm)

    Participants receiving treatment will be evaluated at baseline (T0), at Month 1 (T1), and at Month 3 (T2).

  • +4 more secondary outcomes

Study Arms (2)

Quadriceps Plus Hip Strengthening Group

EXPERIMENTAL

For 3 months, 3 days per week, participants will perform quadriceps strengthening exercises combined with hip abductor and adductor strengthening exercises. In addition to all exercises included in the Quadriceps Strengthening Group, participants will perform: Hip abduction (side-lying position with ankle weights) Clamshell exercise (for gluteus medius activation) Hip adduction (supine position with isometric contraction using a pillow) Side-lying hip abduction with a resistance band

Other: Quadriceps Plus Hip Strengthening Exercises

Quadriceps Strengthening Group

ACTIVE COMPARATOR

For 3 months, 3 days per week, participants will perform a quadriceps strengthening exercise program only. The program will include: Knee extension (in a seated position, with and without resistance) Terminal knee extension Straight leg raise Mini squat (0-30° knee flexion)

Other: Quadriceps Strengthening Exercises

Interventions

quadriceps strengthening exercises combined with hip abductor and adductor strengthening exercises

Quadriceps Plus Hip Strengthening Group

quadriceps strengthening exercise program

Quadriceps Strengthening Group

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Age ≥18 years
  • Diagnosis of knee osteoarthritis according to ACR criteria, Kellgren-Lawrence grade 2-3
  • Knee pain for at least 3 months
  • Having the physical capacity to perform a home exercise program
  • Willingness to provide written informed consent

You may not qualify if:

  • History of knee, hip, or spine surgery
  • Active inflammatory arthritis (e.g., rheumatoid arthritis, gout, psoriatic arthritis)
  • Intra-articular injection within the last 3 months
  • Neurological or neuromuscular disorders
  • Body mass index (BMI) \> 40 kg/m²
  • Pregnancy
  • Cardiovascular or orthopedic contraindications preventing participation in a regular exercise program
  • Cognitive impairment

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Kütahya Physical Therapy and Rehabilitation Hospital

Kütahya, Turkey (Türkiye)

Location

Related Publications (27)

  • Lee CL, Huang MH, Chai CY, Chen CH, Su JY, Tien YC. The validity of in vivo ultrasonographic grading of osteoarthritic femoral condylar cartilage: a comparison with in vitro ultrasonographic and histologic gradings. Osteoarthritis Cartilage. 2008 Mar;16(3):352-8. doi: 10.1016/j.joca.2007.07.013. Epub 2007 Oct 24.

  • Karalilova R, Kazakova M, Batalov A, Sarafian V. Correlation between protein YKL-40 and ultrasonographic findings in active knee osteoarthritis. Med Ultrason. 2018 Feb 4;1(1):57-63. doi: 10.11152/mu-1247.

  • Tuzun EH, Eker L, Aytar A, Daskapan A, Bayramoglu M. Acceptability, reliability, validity and responsiveness of the Turkish version of WOMAC osteoarthritis index. Osteoarthritis Cartilage. 2005 Jan;13(1):28-33. doi: 10.1016/j.joca.2004.10.010.

  • Manske RC, Wolfe C, Page P, Voight M. Diagnostic Musculoskeletal Ultrasound in the Evaluation of Adductor Longus Injuries: Implications for Rehabilitation Providers. Int J Sports Phys Ther. 2025 Nov 1;20(11):1670-1674. doi: 10.26603/001c.146209. eCollection 2025.

  • Whittaker JL, Emery CA. Sonographic measures of the gluteus medius, gluteus minimus, and vastus medialis muscles. J Orthop Sports Phys Ther. 2014 Aug;44(8):627-32. doi: 10.2519/jospt.2014.5315. Epub 2014 Jul 16.

  • Tillquist M, Kutsogiannis DJ, Wischmeyer PE, Kummerlen C, Leung R, Stollery D, Karvellas CJ, Preiser JC, Bird N, Kozar R, Heyland DK. Bedside ultrasound is a practical and reliable measurement tool for assessing quadriceps muscle layer thickness. JPEN J Parenter Enteral Nutr. 2014 Sep;38(7):886-90. doi: 10.1177/0148607113501327. Epub 2013 Aug 26.

  • KELLGREN JH, LAWRENCE JS. Radiological assessment of osteo-arthrosis. Ann Rheum Dis. 1957 Dec;16(4):494-502. doi: 10.1136/ard.16.4.494. No abstract available.

  • Bennell KL, Hunt MA, Wrigley TV, Hunter DJ, McManus FJ, Hodges PW, Li L, Hinman RS. Hip strengthening reduces symptoms but not knee load in people with medial knee osteoarthritis and varus malalignment: a randomised controlled trial. Osteoarthritis Cartilage. 2010 May;18(5):621-8. doi: 10.1016/j.joca.2010.01.010. Epub 2010 Feb 6.

  • Powers CM. The influence of abnormal hip mechanics on knee injury: a biomechanical perspective. J Orthop Sports Phys Ther. 2010 Feb;40(2):42-51. doi: 10.2519/jospt.2010.3337.

  • Bennell KL, Wrigley TV, Hunt MA, Lim BW, Hinman RS. Update on the role of muscle in the genesis and management of knee osteoarthritis. Rheum Dis Clin North Am. 2013 Feb;39(1):145-76. doi: 10.1016/j.rdc.2012.11.003. Epub 2012 Nov 22.

  • Kean CO, Bennell KL, Wrigley TV, Hinman RS. Relationship between hip abductor strength and external hip and knee adduction moments in medial knee osteoarthritis. Clin Biomech (Bristol). 2015 Mar;30(3):226-30. doi: 10.1016/j.clinbiomech.2015.01.008. Epub 2015 Feb 3.

  • Yuenyongviwat V, Duangmanee S, Iamthanaporn K, Tuntarattanapong P, Hongnaparak T. Effect of hip abductor strengthening exercises in knee osteoarthritis: a randomized controlled trial. BMC Musculoskelet Disord. 2020 May 7;21(1):284. doi: 10.1186/s12891-020-03316-z.

  • Segal NA, Nevitt MC, Gross KD, Hietpas J, Glass NA, Lewis CE, Torner JC. The Multicenter Osteoarthritis Study: opportunities for rehabilitation research. PM R. 2013 Aug;5(8):647-54. doi: 10.1016/j.pmrj.2013.04.014.

  • Deasy M, Leahy E, Semciw AI. Hip Strength Deficits in People With Symptomatic Knee Osteoarthritis: A Systematic Review With Meta-analysis. J Orthop Sports Phys Ther. 2016 Aug;46(8):629-39. doi: 10.2519/jospt.2016.6618. Epub 2016 Jul 3.

  • Thomas DT, R S, Prabhakar AJ, Dineshbhai PV, Eapen C. Hip abductor strengthening in patients diagnosed with knee osteoarthritis - a systematic review and meta-analysis. BMC Musculoskelet Disord. 2022 Jun 29;23(1):622. doi: 10.1186/s12891-022-05557-6.

  • Eijking HM, Verlaan L, Emans P, Boymans T, Meijer K, Senden R. Patient with knee osteoarthritis demonstrates improved knee adduction moment after knee joint distraction: a case report. Acta Orthop Belg. 2024 Mar;90(1):147-153. doi: 10.52628/90.1.11515.

  • Lewis CL, Segal NA, Rabasa GV, LaValley MP, Williams GN, Nevitt MC, Lewis CE, Felson DT, Stefanik JJ. Hip Abductor Weakness and Its Association With New or Worsened Knee Pain: Data From the Multicenter Osteoarthritis Study. Arthritis Care Res (Hoboken). 2023 Nov;75(11):2328-2335. doi: 10.1002/acr.25160. Epub 2023 Jun 22.

  • Bozan A, Erhan B. The relationship between quadriceps femoris thickness measured by US and femoral cartilage thickness in knee osteoarthritis, its effect on radiographic stage and clinical parameters: comparison with healthy young population. J Frailty Sarcopenia Falls. 2023 Sep 1;8(3):155-162. doi: 10.22540/JFSF-08-155. eCollection 2023 Sep.

  • Tuna S, Balci N, Ozcakar L. The relationship between femoral cartilage thickness and muscle strength in knee osteoarthritis. Clin Rheumatol. 2016 Aug;35(8):2073-2077. doi: 10.1007/s10067-016-3271-4. Epub 2016 Apr 18.

  • Kolasinski SL, Neogi T, Hochberg MC, Oatis C, Guyatt G, Block J, Callahan L, Copenhaver C, Dodge C, Felson D, Gellar K, Harvey WF, Hawker G, Herzig E, Kwoh CK, Nelson AE, Samuels J, Scanzello C, White D, Wise B, Altman RD, DiRenzo D, Fontanarosa J, Giradi G, Ishimori M, Misra D, Shah AA, Shmagel AK, Thoma LM, Turgunbaev M, Turner AS, Reston J. 2019 American College of Rheumatology/Arthritis Foundation Guideline for the Management of Osteoarthritis of the Hand, Hip, and Knee. Arthritis Care Res (Hoboken). 2020 Feb;72(2):149-162. doi: 10.1002/acr.24131. Epub 2020 Jan 6.

  • Moseng T, Vliet Vlieland TPM, Battista S, Beckwee D, Boyadzhieva V, Conaghan PG, Costa D, Doherty M, Finney AG, Georgiev T, Gobbo M, Kennedy N, Kjeken I, Kroon FPB, Lohmander LS, Lund H, Mallen CD, Pavelka K, Pitsillidou IA, Rayman MP, Tveter AT, Vriezekolk JE, Wiek D, Zanoli G, Osteras N. EULAR recommendations for the non-pharmacological core management of hip and knee osteoarthritis: 2023 update. Ann Rheum Dis. 2024 May 15;83(6):730-740. doi: 10.1136/ard-2023-225041.

  • Mo L, Jiang B, Mei T, Zhou D. Exercise Therapy for Knee Osteoarthritis: A Systematic Review and Network Meta-analysis. Orthop J Sports Med. 2023 Jun 5;11(5):23259671231172773. doi: 10.1177/23259671231172773. eCollection 2023 May.

  • Hwang HS, Kim HA. Chondrocyte Apoptosis in the Pathogenesis of Osteoarthritis. Int J Mol Sci. 2015 Oct 30;16(11):26035-54. doi: 10.3390/ijms161125943.

  • Sanchez-Lopez E, Coras R, Torres A, Lane NE, Guma M. Synovial inflammation in osteoarthritis progression. Nat Rev Rheumatol. 2022 May;18(5):258-275. doi: 10.1038/s41584-022-00749-9. Epub 2022 Feb 14.

  • Cay HF, Akinci A, Altan L, Ataman S, Aydogdu S, Diracoglu D, Genc H, Hepguler S, Ketenci A, Ones K, Uyar M, Gumru S, Hacibedel B, Helvacioglu K, Olmez A, Tuncer T. Evaluation of disease burden, patient journey, unmet diagnosis and treatment needs of patients with HIP and knee osteoarthritis in Turkey: A study through Delphi Methodology. Osteoarthr Cartil Open. 2022 Dec 24;5(1):100332. doi: 10.1016/j.ocarto.2022.100332. eCollection 2023 Mar.

  • Cui A, Li H, Wang D, Zhong J, Chen Y, Lu H. Global, regional prevalence, incidence and risk factors of knee osteoarthritis in population-based studies. EClinicalMedicine. 2020 Nov 26;29-30:100587. doi: 10.1016/j.eclinm.2020.100587. eCollection 2020 Dec.

  • Li E, Tan J, Xu K, Pan Y, Xu P. Global burden and socioeconomic impact of knee osteoarthritis: a comprehensive analysis. Front Med (Lausanne). 2024 May 16;11:1323091. doi: 10.3389/fmed.2024.1323091. eCollection 2024.

Central Study Contacts

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
SINGLE
Who Masked
OUTCOMES ASSESSOR
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Medical Specialist

Study Record Dates

First Submitted

June 14, 2026

First Posted

June 18, 2026

Study Start (Estimated)

August 20, 2026

Primary Completion (Estimated)

April 1, 2027

Study Completion (Estimated)

July 1, 2027

Last Updated

June 22, 2026

Record last verified: 2026-06

Data Sharing

IPD Sharing
Will not share

Locations