Popliteus and Quadriceps Muscle Thickness and Clinical Parameters in Knee Osteoarthritis

NCT07834827 | Active Not Recruiting

• 1 other identifier: 2026/505
• Study Type: observational
• Target: 130
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to examine the relationships between the ultrasonographic muscle thicknesses of the popliteus and quadriceps muscles and functional capacity, balance, and pain levels in elderly patients with knee osteoarthritis (KOA). Knee osteoarthritis is a major degenerative joint disorder causing pain, stiffness, and reduced mobility, where surrounding muscle architecture plays a pivotal role in functional performance and joint stability. The study will recruit approximately 150 participants aged 65 years and older with Grade 3-4 KOA (Kellgren-Lawrence) and intact cognitive status (SMMSE score ≥24) presenting to the Physical Medicine and Rehabilitation Outpatient Clinic of Afyonkarahisar Health Sciences University Health Application and Research Center, while excluding individuals with central nervous system, visual pathologies, or prior lower extremity surgeries. Muscle thicknesses of the popliteus and quadriceps (rectus femoris and vastus intermedius) will be measured via high-frequency B-mode ultrasonography by a specialist physician, using standardized anatomical landmarks and patient positioning. Functional capacity and mobility will be evaluated using the Timed Up and Go (TUG) and 5-Times Sit-to-Stand (5STS) tests, balance and proprioception via the Romberg Test, and knee-specific functional status and pain severity using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Visual Analog Scale (VAS).

Conditions

Knee Arthritis Osteoarthritis; Balance Assessment

Keywords

knee osteoarthritis

Outcome Measures

Primary Outcomes (7)

• Ultrasound measurement of popliteus and quadriceps muscle thickness

  Popliteus and quadriceps (rectus femoris + vastus intermedius) muscle thickness will be measured via B-mode ultrasonography using a high-frequency linear probe (10-15 MHz), with three measurements averaged per muscle. The correlation between mean popliteus and mean quadriceps thickness (mm) will be assessed using Pearson or Spearman correlation coefficients, depending on data distribution.

  Baseline (single assessment visit)

• Timed Up and Go Test (TUG):

  The participant sits on a standard armless chair (43-46 cm height); upon the "start" command, they stand up, walk a marked 3-meter distance, turn, walk back to the chair, and sit down. The time elapsed from the start command until the participant sits down is recorded in seconds. The individual wears comfortable footwear, walks at a normal walking speed, and any standard assistive devices (e.g., cane) used are noted

  baseline

• 5-Times Sit-to-Stand Test (5STS)

  It is a reliable test used to assess sitting and standing ability. In older adults, it evaluates functional mobility, lower extremity muscle strength, and balance (19). The participant crosses their arms over their chest, and the time required to complete 5 consecutive sit-to-stand repetitions is measured.

  Baseline

• Knee Injury and Osteoarthritis Outcome Score (KOOS)

  KOOS is a comprehensive and reliable instrument for knee injuries and knee osteoarthritis. The scale consists of 5 subscales: Pain (9 items), Other Symptoms (7 items), Function in Daily Living (ADL) (17 items), Sport/Recreation Function (5 items), and Knee-Related Quality of Life (4 items). Each subscale is normalized to a score of 0-100, where 100 indicates no problems and 0 indicates extreme problems

  Baseline

• Romberg Test

  The patient is asked to stand upright with their feet together and arms hanging freely at their sides.The patient must wear hard, thin-soled shoes during this test. Without receiving any support, the patient is asked to stand first with eyes open and then with eyes closed. Safety precautions must be taken during this test to prevent falls; the examiner must remain close to the patient at all times and be prepared to catch them if they fall. In peripheral vestibular pathologies, the direction of sway/fall is toward the side of the lesion

  Baseline

• Visual Analog Scale (VAS)

  Participants will be asked to mark their average perceived pain intensity on a 10-centimeter (cm) line (defined as 0 = no pain, 10 = unbearable pain) during rest, activity, and sleep. Baseline pain scores will be obtained by measuring the distance between the marked point and the zero point using a ruler

  Baseline

• Standardized Mini-Mental State Examination (SMMSE)

  Developed by Folstein et al. in 1975 to assess cognitive status in adults. Its validity and reliability for the Turkish population were conducted by Güngen et al. A modified version is also available for individuals with less than five years of education. SMMSE is categorized under five main headings: orientation (10 points), registration/memory (3 points), attention and calculation (5 points), recall (3 points), and language (9 points). The scale is evaluated out of a total of 30 points. In scoring: results between 24 and 30 points indicate "normal" cognitive status, 18 to 23 points indicate "mild dementia," 12 to 17 points indicate "moderate dementia," and scores below 12 indicate "severe dementia" (Güngen et al., 2002). Individuals scoring 24 and above on the SMMSE were included in our study.

  Baseline

Study Arms (1)

Knee OA Patients

Elderly patients diagnosed with knee osteoarthritis who meet the inclusion criteria. Popliteus and quadriceps muscle thickness will be measured using ultrasonography, and their relationship with functional capacity, balance, and pain levels will be evaluated.

Eligibility Criteria

• Age: 65 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

Participants for this study will consist of individuals aged 65 years and older diagnosed with Grade 3 and Grade 4 knee osteoarthritis according to the Kellgren-Lawrence classification by a specialist physician, presenting to the Physical Medicine and Rehabilitation Outpatient Clinic of Afyonkarahisar Health Sciences University Health Application and Research Center. All evaluations within the scope of the study will be performed at the Physical Medicine and Rehabilitation Outpatient Clinic of Afyonkarahisar Health Sciences University Health Application and Research Center. Ultrasound (US) evaluations of the participants classified under Kellgren-Lawrence Grade 3 and Grade 4 will be performed.

You may qualify if:

• Individuals aged 65 years and older
• Individuals with a Standardized Mini-Mental State Examination (SMMSE) score of 24 and above
• Individuals classified as Grade 3-4 according to the Kellgren-Lawrence grading scale

You may not qualify if:

• Individuals under the age of 65
• Individuals with an SMMSE score below 24
• Individuals with central nervous system and visual pathologies that may affect balance
• Individuals with a history of lower extremity surgery

Sponsors & Collaborators

• Afyonkarahisar Health Sciences University: lead

Study Sites (1)

Afyonkarahisar Health Science University

Merkez, Afyonkarahisar, Turkey (Türkiye)

Location

MeSH Terms

Conditions

Osteoarthritis, Knee

Condition Hierarchy (Ancestors)

Osteoarthritis; Arthritis; Joint Diseases; Musculoskeletal Diseases; Rheumatic Diseases

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: asist. prof.

Study Record Dates

• First Submitted: September 17, 2026
• First Posted: September 22, 2026
• Study Start: August 20, 2026
• Primary Completion (Estimated): August 1, 2027
• Study Completion (Estimated): August 1, 2028
• Last Updated: September 22, 2026

Record last verified: 2026-09

Locations

TU (1)