{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T19:14:54Z","timestamp":1790709294900,"version":"4.1.0"},"reference-count":17,"publisher":"International Journal of Sports Physical Therapy","issue":"1","license":[{"start":{"date-parts":[[2026,1,1]],"date-time":"2026-01-01T00:00:00Z","timestamp":1767225600000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>Fibrosis of the infrapatellar fat pad (Hoffa\u2019s disease) is a frequently missed cause of anterior knee pain in young, active individuals. A diagnostic test that involves injection of the infrapatellar fat pad with local anesthetic and subsequent stress with treadmill running, is a simple in office strategy to effectively diagnose pathology of the fat pad. Selective arthroscopic debridement of the fat pad using superolateral viewing portal aids in adequate visualization not otherwise feasible using standard anterior viewing portals alone.<\/jats:p>\n                  <jats:p>The purpose of this case report is to describe two cases of anterior knee pain arising from fibrosis of the infrapatellar fat pad as identified on imaging and arthroscopy. Both patients were found to suffer from pain arising from a fibrotic infrapatellar fat pad and responded well to surgical intervention.<\/jats:p>\n                  <jats:sec id=\"level-of-evidence\">\n                    <jats:title>Level of Evidence<\/jats:title>\n                    <jats:p>5<\/jats:p>\n                  <\/jats:sec>","DOI":"10.26603\/001c.153923","type":"journal-article","created":{"date-parts":[[2025,12,31]],"date-time":"2025-12-31T22:03:39Z","timestamp":1767218619000},"source":"Crossref","is-referenced-by-count":1,"title":["Chronic Infrapatellar Fat Pad Fibrosis: Hoffa\u2019s Disease, a Commonly Unrecognized Source of Anterior Knee Pain \u2013 A Report of Two Cases"],"prefix":"10.26603","volume":"21","author":[{"given":"Brendan","family":"Swift","sequence":"first","affiliation":[{"name":"Cincinnati Sports Medicine Research and Education Foundation"},{"name":"Mercy Health- Cincinnati Sports Medicine and Orthopaedic Center"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frank","family":"Noyes","sequence":"additional","affiliation":[{"name":"Cincinnati Sports Medicine Research and Education Foundation"},{"name":"Mercy Health- Cincinnati Sports Medicine and Orthopaedic Center"},{"name":"Noyes Knee Institute"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"11140","published-online":{"date-parts":[[2026,1,1]]},"reference":[{"issue":"2","key":"ref1","doi-asserted-by":"publisher","first-page":"108","DOI":"10.1136\/ard.62.2.108","article-title":"Cytokine production in the infrapatellar fat pad: another source of cytokines in knee synovial fluids","volume":"62","author":"T. 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Dragoo","year":"2012","journal-title":"Sports Med"},{"issue":"4","key":"ref11","doi-asserted-by":"publisher","first-page":"268","DOI":"10.1007\/s00167-004-0592-7","article-title":"The infrapatellar fat pad: Anatomy and clinical correlations","volume":"13","author":"J. Gallagher","year":"2005","journal-title":"Knee Surg Sports Traumatol Arthrosc"},{"issue":"8","key":"ref12","doi-asserted-by":"publisher","first-page":"1873","DOI":"10.1177\/0363546504263946","article-title":"Biomechanical and kinematic influences of a total infrapatellar fat pad resection on the knee","volume":"32","author":"M. Bohnsack","year":"2004","journal-title":"Am J Sports Med"},{"issue":"11","key":"ref13","doi-asserted-by":"publisher","first-page":"3515","DOI":"10.1007\/s00167-018-4943-1","article-title":"The infrapatellar fat pad is a dynamic and mobile structure, which deforms during knee motion, and has proximal extensions which wrap around the patella","volume":"26","author":"J. M. Stephen","year":"2018","journal-title":"Knee Surg Sports Traumatol Arthrosc"},{"key":"ref14","doi-asserted-by":"publisher","first-page":"117364","DOI":"10.1016\/j.biopha.2024.117364","article-title":"The biphasic role of the infrapatellar fat pad in osteoarthritis","volume":"179","author":"S. Yue","year":"2024","journal-title":"Biomed Pharmacol"},{"issue":"4","key":"ref15","doi-asserted-by":"publisher","first-page":"R145","DOI":"10.1186\/ar4607","article-title":"Infrapatellar fat pad in the knee: is local fat good or bad for knee osteoarthritis?","volume":"16","author":"W. Han","year":"2014","journal-title":"Arthritis Res Ther"},{"key":"ref16","doi-asserted-by":"publisher","first-page":"110931","DOI":"10.1016\/j.jbiomech.2021.110931","article-title":"Mechanical behavior of infrapatellar fat pad of patients affected by osteoarthritis","volume":"131","author":"C. G. Fontanella","year":"2022","journal-title":"J Biomech"},{"key":"ref17","doi-asserted-by":"publisher","first-page":"342","DOI":"10.1002\/jor.20498","article-title":"Preponderance of sensory versus sympathetic nerve fibers and increased cellularity in the infrapatellar fat pad in anterior knee pain patients after primary arthroplasty","volume":"26","author":"B. Lehner","year":"2008","journal-title":"J Orthop Res"}],"container-title":["International Journal of Sports Physical Therapy"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/ijspt.scholasticahq.com\/article\/153923-chronic-infrapatellar-fat-pad-fibrosis-hoffa-s-disease-a-commonly-unrecognized-source-of-anterior-knee-pain-a-report-of-two-cases","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,2]],"date-time":"2026-01-02T22:05:56Z","timestamp":1767391556000},"score":1,"resource":{"primary":{"URL":"https:\/\/ijspt.scholasticahq.com\/article\/153923-chronic-infrapatellar-fat-pad-fibrosis-hoffa-s-disease-a-commonly-unrecognized-source-of-anterior-knee-pain-a-report-of-two-cases"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,1]]},"references-count":17,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026]]}},"URL":"https:\/\/doi.org\/10.26603\/001c.153923","relation":{},"ISSN":["2159-2896"],"issn-type":[{"value":"2159-2896","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,1]]}}}