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

NCT ID: NCT03763448

Last Updated: 2025-12-05

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 377 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2018-12-17
• Study Completion Date: 2024-05-13

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.

Detailed Description

Knee Osteoarthritis (KOA) is a common chronic disease, which often leads to joint pain and limited function in the elderly, and thus affects participants' quality of life. Total knee arthroplasty (TKA) has been developed as a mature surgical procedure to relieve end-stage osteoarthritic joint pain and improve limb function. Although more than 80% of the patients reported in the literature are satisfied with the postoperative efficacy of TKA, there are still a large number of patients whose daily life is affected by persistent knee pain and limited function after the operation of the affected limb.

The IPFP is a fat mass located behind the patellar ligament, between the lower part of the patella and the tibial tubercle. The function of IPFP is controversial at present. It is reported that IPFP can provide blood supply for anterior cruciate ligament, patella and patellar ligament through the arterial network of the knee joint. In addition, it can fill the joint gap to lubricate the surface of the joint, reduce friction and absorb impulse so as to play a physiological protective role. On the contrary, studies have pointed out that abnormal IPFP could produce various pro-inflammatory cytokines such as interleukin (IL)-1β, tumour necrosis factor (TNF)-α, IL-6 and IL-8, as well as adipokines such as leptin and resistin, and thus might play a detrimental role in knee OA. Traditionally, the IPFP has been removed in order to improve surgical exposure and to prevent interposition during baseplate implantation. Despite the significant evolution of TKA technology which no longer requires the resection of IPFP for better surgical access, IPFP is still partially or totally resected in around 88% of TKAs.

The investigators' previous population-based cohort study revealed that IPFP maximal area and volume were associated with reduced knee pain, decreased loss of cartilage volume and reduced risks of cartilage defect progression, indicating a beneficial effect of IPFP size. On the other hand, the investigators' further investigation demonstrated that IPFP signal intensity alteration was negatively associated with maximum area of IPFP, and moreover, associated with increased knee cartilage defects, subchondral bone marrow lesion (BML) and knee pain, suggesting IPFP with abnormal quality may play a detrimental role in knee OA. Based on these findings, the investigators proposed that IPFP with normal quality should be preserved or not damaged during TKA, while IPFP with abnormal quality should be resected. This multicentre randomised controlled trial is designed to test the investigators' hypotheses: in patients with normal IPFP quality, preservation of IPFP during TKA procedure will reduce postoperative knee symptoms and improve joint function, comparing with IPFP resection during TKA procedures; in patients with abnormal IPFP quality, resection of IPFP during TKA procedure will reduce postoperative knee symptoms and improve joint function, comparing with IPFP preservation during TKA procedures. The results would provide evidence-based recommendations on clinical practice to improve OA patients' postoperative outcomes.

Three hundred and sixty eligible participants will be recruited and identified as having normal IPFP quality (signal intensity alteration score ≤ 1) or abnormal IPFP quality (signal intensity alteration score ≥ 2). Participants in each site will be randomly allocated to IPFP resection group or preservation group using computer-generated block randomisation.

Conditions

Knee Osteoarthritis; Arthropathy of Knee

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: TRIPLE

Study Groups

Infrapatellar Fat Pad Preservation

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

Group Type: EXPERIMENTAL

Infrapatellar Fat Pad preservation

Intervention Type: PROCEDURE

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

Infrapatellar Fat Pad Resection

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.

Group Type: ACTIVE_COMPARATOR

Infrapatellar Fat Pad resection

Intervention Type: PROCEDURE

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

Interventions

Infrapatellar Fat Pad preservation

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

Intervention Type: PROCEDURE

Infrapatellar Fat Pad resection

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

Intervention Type: PROCEDURE

Other Intervention Names

Infrapatellar fat pad retention

Eligibility Criteria

Inclusion Criteria

• 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

Exclusion Criteria

• 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

• Minimum Eligible Age: 40 Years
• Maximum Eligible Age: 80 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Tianjin Hospital

OTHER

Sponsor Role: collaborator

Peking University People's Hospital

OTHER

Sponsor Role: collaborator

The First Affiliated Hospital of Anhui Medical University

OTHER

Sponsor Role: collaborator

First Affiliated Hospital of Jinan University

OTHER

Sponsor Role: collaborator

Anhui Provincial Hospital

OTHER_GOV

Sponsor Role: collaborator

Youjiang Medical College for Nationalities

OTHER

Sponsor Role: collaborator

Xiangya Hospital of Central South University

OTHER

Sponsor Role: collaborator

Zhujiang Hospital

OTHER

Sponsor Role: lead

Responsible Party

Ding Changhai

Director,Clinical Research Center

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Changhai Ding, MD

Role: PRINCIPAL_INVESTIGATOR

Clinical Research Center of Zhujiang Hospital,Southern Medical University

Jianhao Lin, MD

Role: PRINCIPAL_INVESTIGATOR

Peking University People's Hospital

Xisheng Weng, MD

Role: PRINCIPAL_INVESTIGATOR

Peking Union Medical College Hospital

Guanghua Lei, MD

Role: PRINCIPAL_INVESTIGATOR

Xiangya Hospital of Central South University

Zongsheng Yin, MD

Role: PRINCIPAL_INVESTIGATOR

The First Affiliated Hospital of Anhui Medical University

Zhengang Zha, MD

Role: PRINCIPAL_INVESTIGATOR

First Affiliated Hospital of Jinan University

Jing Tian, MD

Role: PRINCIPAL_INVESTIGATOR

Zhujiang Hospital

Xifu Shang, MD

Role: PRINCIPAL_INVESTIGATOR

Anhui Provincial Hospital

Yujin Tang, MD

Role: PRINCIPAL_INVESTIGATOR

Youjiang Medical College for Nationalities

Jun Liu, MD

Role: PRINCIPAL_INVESTIGATOR

Tianjin Hospital

Locations

Zhujiang Hospital

Guangzhou, Guangdong, China

Countries

China

References

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.

Reference Type: DERIVED

PMID: 33099502 (View on PubMed)

Other Identifiers

2017-GJGBK-001

Identifier Type: -

Identifier Source: org_study_id