Infrapatellar Fat Pad Preservation Versus Resection on Clinical Outcomes After Total Knee Arthroplasty(IPAKA)

NCT03763448 | Completed

• 1 other identifier: 2017-GJGBK-001
• Study Type: interventional
• Target: 377
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to compare the postoperative clinical outcomes of Infrapatellar Fat Pad (IPFP) preservation versus resection after total knee arthroplasty (TKA) in patients with knee osteoarthritis. Participants will be identified as normal IPFP or abnormal IPFP based on MRI findings before randomization. The primary outcome is the change from baseline to 12 months in the mean score on five Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales (KOOS5), covering pain, symptoms, activities of daily life, sport \& recreation, knee-related quality of life, with scores ranging from 0 (worst) to 100 (best). The secondary endpoints will be included: KOOS subscales, Knee Society Score (KSS), 100 mm Visual Analogue Scale (VAS) Pain, timed up-and-go test, depression, patellar tendon shortening, 100 mm VAS self-reported efficacy of reduced pain and increased quality of life. Adverse events will be recorded. Primary and secondary outcomes will be evaluated or reported blindly at baseline and at postoperative 3 months, 6 months, and 1 year. Intention-to-treat analyses will be used.

Conditions

Arthropathy of Knee; Knee Osteoarthritis

Keywords

Infrapatellar Fat Pad; Knee Osteoarthritis; Total Knee Arthroplasty; Randomized Clinical Trial

Outcome Measures

Primary Outcomes (1)

• The mean score on five Knee Injury and Osteoarthritis Outcome Score(KOOS) subscales

  The primary outcome was the change from baseline to 12 months in the mean score on five Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales, covering pain, symptoms, activities of daily living, sport and recreation function, and knee-related quality of life (KOOS5), with scores ranging from 0 (worst) to 100 (best). The KOOS, a valid, reliable and responsive self-reported questionnaire applied to evaluate the short and long-term patient-relevant outcomes following TKA, consists of five subscales with a total of 42 items: pain (9 items), symptoms (7 items), function in ADL (17 items), sport and recreation function (5 items) and knee-related quality of life (4 items).

  From pre-operation to 12 months after operation

Secondary Outcomes (6)

• Five individual subscales of Knee Injury and Osteoarthritis Outcome Score (KOOS)

  From pre-operation to 12 months after operation

• Knee Society Score(KSS)

  From pre-operation to 12 months after operation

• Self-reported efficacy of reduced pain and increased quality of life

  From pre-operation to 12 months after operation

• Insall - Salvati Ratio (ISR)

  From pre-operation to 12 months after operation

• Timed Up and Go test

  From pre-operation to 12 months after operation

Study Arms (2)

Infrapatellar Fat Pad Preservation

EXPERIMENTAL

The IPFP retention of more than 80% in actual operation shall be regarded as IPFP retention.

Procedure: Infrapatellar Fat Pad preservation

Infrapatellar Fat Pad Resection

ACTIVE COMPARATOR

In the clinical practice, more than 80% of IPFP volume is commonly resected by surgeons during total knee arthroplasty. The investigators hereby define resection of more than 80% IPFP volume as IPFP excision.

Procedure: Infrapatellar Fat Pad resection

Interventions

Infrapatellar Fat Pad preservation PROCEDURE

In the IPFP preservation group, IPFP (more than 80%) will be preserved by retracting out of the operative field.

Also known as: Infrapatellar fat pad retention

Infrapatellar Fat Pad Preservation

Infrapatellar Fat Pad resection PROCEDURE

In the IPFP resection group, more than 80% IPFP will be resected during the total knee arthroplasty.

Infrapatellar Fat Pad Resection

Eligibility Criteria

• Age: 40 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Participants diagnosed with knee osteoarthritis by X-ray plain film (Kellgren-Lawrence score of ≥ 2)
• The need for TKA was confirmed after evaluation by the orthopedic surgeon
• One week before surgery, knee pain 100mm pain visual analogue scale score was greater than 20mm
• Understanding of the study requirements and willing to participate in this study

You may not qualify if:

• Rheumatoid arthritis,psoriatic arthritis,lupus,malignant tumor
• Requiring contralateral TKA within one year
• The visual analogue score of 100mm of knee pain before operation was less than 20mm
• Having a possible or planned pregnancy
• With poor compliance
• Suffering from somatic disease, psychiatric or cognitive disorders, neurological disorders that will compromise the safety, compliance, consent, participation, follow-up and the interpretation of the results
• Severe knee valgus
• Contraindications with TKA or MRI

Sponsors & Collaborators

• Zhujiang Hospital: lead
• The First Affiliated Hospital of Anhui Medical University: collaborator
• First Affiliated Hospital of Jinan University: collaborator
• Anhui Provincial Hospital: collaborator
• Tianjin Hospital: collaborator
• Youjiang Medical College for Nationalities: collaborator
• Xiangya Hospital of Central South University: collaborator
• Peking University People's Hospital: collaborator

Study Sites (1)

Zhujiang Hospital

Guangzhou, Guangdong, 510285, China

Location

Related Publications (2)

• Han W, Cao P, Cen H, Li B, Chen M, Li Y, Yang C, Lu M, Zhang H, Ke Y, Zhu Z, Liu X, Gao P, Zhou X, Liu Y, Dou Z, Liu Y, Zhang M, Lin J, Zha Z, Yin Z, Tian J, Lin L, Shang X, Hunter DJ, Liu J, Lei G, Ding C. Infrapatellar Fat Pad Preservation versus Resection in Total Knee Arthroplasty. NEJM Evid. 2026 Apr;5(4):EVIDoa2500135. doi: 10.1056/EVIDoa2500135. Epub 2026 Mar 24.

  PMID: 41874257 DERIVED

• Zhu Z, Han W, Lu M, Lin J, Yin Z, Shang X, Weng X, Zha Z, Tian J, Lei G, Hunter DJ, Ding C. Effects of infrapatellar fat pad preservation versus resection on clinical outcomes after total knee arthroplasty in patients with knee osteoarthritis (IPAKA): study protocol for a multicentre, randomised, controlled clinical trial. BMJ Open. 2020 Oct 23;10(10):e043088. doi: 10.1136/bmjopen-2020-043088.

  PMID: 33099502 DERIVED

MeSH Terms

Conditions

Osteoarthritis, Knee

Condition Hierarchy (Ancestors)

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

Study Officials

• Changhai Ding, MD

  Clinical Research Center of Zhujiang Hospital,Southern Medical University

  PRINCIPAL INVESTIGATOR

• Jianhao Lin, MD

  Peking University People's Hospital

  PRINCIPAL INVESTIGATOR

• Xisheng Weng, MD

  Peking Union Medical College Hospital

  PRINCIPAL INVESTIGATOR

• Guanghua Lei, MD

  Xiangya Hospital of Central South University

  PRINCIPAL INVESTIGATOR

• Zongsheng Yin, MD

  The First Affiliated Hospital of Anhui Medical University

  PRINCIPAL INVESTIGATOR

• Zhengang Zha, MD

  First Affiliated Hospital of Jinan University

  PRINCIPAL INVESTIGATOR

• Jing Tian, MD

  Zhujiang Hospital

  PRINCIPAL INVESTIGATOR

• Xifu Shang, MD

  Anhui Provincial Hospital

  PRINCIPAL INVESTIGATOR

• Yujin Tang, MD

  Youjiang Medical College for Nationalities

  PRINCIPAL INVESTIGATOR

• Jun Liu, MD

  Tianjin Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: participants, outcome assessors, data analysts and chief investigators are masked during the study procedure.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Director,Clinical Research Center

Study Record Dates

• First Submitted: October 19, 2018
• First Posted: December 4, 2018
• Study Start: December 17, 2018
• Primary Completion: May 13, 2024
• Study Completion: May 13, 2024
• Last Updated: December 5, 2025

Record last verified: 2025-11

Locations

CN (1)