Elasticity of the Hoffa's Fat Pad in Patients With Knee Osteoarthritis

Knee osteoarthritis (OA) is a common problem in clinical settings. Knee OA is well known for its association with the wear and tear of the cartilage and osteophyte formation. Evidence has suggested the importance of the infrapatellar fat pad, known as Hoffa's fat pad, during the development of knee OA. Some studies have demonstrated the protective role of the infrapatellar fat pad, whereas others have suggested an inflammatory role such as increased fibrosis and proinflammatory cytokine levels. Ultrasound is exceptionally convenient in the assessment of the musculoskeletal system, and elastography is a tool to evaluate tissue texture. Therefore, in this study, we investigated the Hoffa's fat pad in knee OA patients by using elastography.

Study Overview

• Status: Completed
• Conditions: Knee Osteoarthritis; Elasticity Imaging Techniques

Detailed Description

This was an observation study that included a control group. We enrolled 20 patients with knee OA, as well as 10 healthy individuals. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Kellgren-Lawrence X-ray grading were employed to determine disease severity. All the study participants received elastography assessment, including strain and shear wave elastography in the knee extension and flexion position. The strain elastography contained color mapping that enabled the calculation of the relative texture and strain ratio. The shear wave elastography revealed the qualitative velocity, which was measured 3 times. Each patients with knee OA received elastography examination twice: once before hyaluronic acid injection and once 1 month after the injection.

• Study Type: Observational
• Enrollment (Actual): 33

Contacts and Locations

Study Locations

• Taiwan
  • Taipei, Taiwan
    • Taipei Veterans General Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 86 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

individuals with knee osteoarthritis diagnosis is classified as K-L grading I - IV individuals in control group has no knee pain or osteoarthritis history

Description

Inclusion Criteria:

OA group

• Kellgren-Lawrence grading I-IV proved by knee X-ray Healthy group
• No knee pain or received injection during the past 1 year
• No history of knee OA

Exclusion Criteria:

• History of knee surgery, trauma or malignancy
• History of patellar tendinopathy or patellofemoral pain syndrome
• Refused informed consent

Study Plan

How is the study designed?

Design Details

• Observational Models: Other
• Time Perspectives: Prospective

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
knee osteoarthritis group; individuals being diagnosed with osteoarthritis and classified by K-L grading
healthy group; individuals without knee pain or diagnosis of knee osteoarthritis

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
shear modulus	the absolute quantitative measurement of elasticity (kPa) of Hoffa's fat pad	before and 1-3 months after hyaluronic acid injection
strain ratio	the semiquantitative measurement of elasticity of Hoffa's fat pad, a ratio with patellar tendon as reference	before and 1-3 months after hyaluronic acid injection
thickness of Hoffa's fat pad	the thickness of Hoffa's fat pad from mid patellar tendon to femur cartilage	before and 1-3 months after hyaluronic acid injection

Collaborators and Investigators

• Sponsor: Taipei Veterans General Hospital, Taiwan
• Investigators: Study Chair: Ding-Hao Liu, Physical and Rehabilitation Medicine, Veterans General Hospital

Study record dates

Study Major Dates

• Study Start (Actual): December 3, 2021
• Primary Completion (Actual): April 11, 2022
• Study Completion (Actual): August 5, 2022

Study Registration Dates

• First Submitted: May 19, 2022
• First Submitted That Met QC Criteria: June 27, 2022
• First Posted (Actual): June 30, 2022

Study Record Updates

• Last Update Posted (Estimate): February 22, 2023
• Last Update Submitted That Met QC Criteria: February 20, 2023
• Last Verified: February 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Joint Diseases; Musculoskeletal Diseases; Rheumatic Diseases; Arthritis; Osteoarthritis; Osteoarthritis, Knee
• Other Study ID Numbers: 2021-09-013AC

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No