J Knee Surg 2017; 30(07): 639-646
DOI: 10.1055/s-0037-1604447
Special Focus Section
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Infrapatellar Fat Pad Impingement: A Systematic Review

Jason Genin
1   Department of Orthopaedic Surgery, Cleveland Clinic, Cleveland, Ohio
Mhamad Faour
1   Department of Orthopaedic Surgery, Cleveland Clinic, Cleveland, Ohio
Prem N. Ramkumar
2   Department of Orthopedics, Cleveland Clinic, Cleveland, Ohio
George Yakubek
1   Department of Orthopaedic Surgery, Cleveland Clinic, Cleveland, Ohio
Anton Khlopas
2   Department of Orthopedics, Cleveland Clinic, Cleveland, Ohio
Morad Chughtai
1   Department of Orthopaedic Surgery, Cleveland Clinic, Cleveland, Ohio
Michael A. Mont
2   Department of Orthopedics, Cleveland Clinic, Cleveland, Ohio
Dominic King
1   Department of Orthopaedic Surgery, Cleveland Clinic, Cleveland, Ohio
› Author Affiliations
Further Information

Publication History

17 February 2017

25 June 2017

Publication Date:
25 July 2017 (online)


Infrapatellar fat pad impingement represents a source of anterior knee pain that is often overlooked. Due to the scarcity of reports related to this disorder, we conducted a systematic review of the literature related to infrapatellar fat pad impingement in evaluating the following: (1) clinical presentation, (2) imaging, (3) management, and (4) clinical outcomes. A systematic review was conducted investigating all available primary literature related to the clinical presentation, imaging, management, and outcomes of infrapatellar fat pad impingement syndrome. A total of 15 studies (9 case reports, 1 case series, and 5 retrospective studies) comprising 167 patients met eligibility criteria for this review. Patients with infrapatellar fat pad impingement were found to most often present with anterior knee pain that worsened with activity, and was frequently associated with trauma. Anterior knee pain, tenderness to palpation over the patellar tendon, loss in terminal extension, and pain with direct pressure on the medial or lateral side of the patella with the knee extended was often found on examination. Although patients may have classic imaging findings on magnetic resonance imaging (localized edema of the infrapatellar fat pad, deep fluid-filled infrapatellar bursa, nonvisualization of clefts, fibrosis, and calcifications), not all patients had positive imaging findings, thus making infrapatellar fat pad impingement a clinical diagnosis. Treatment begins with nonoperative management, but in recalcitrant cases, patients can be surgically treated with arthroscopic fat pad resection. Most patients who undergo operative treatment report improvement or complete resolution of symptoms in terms of pain and range of motion, and are able to return to work. To the best of our knowledge, this is the first comprehensive review on infrapatellar fat pad impingement to better aid the orthopaedic surgeons in diagnosing, treating, and managing patient expectations for this often overlooked knee pathology.

  • References

  • 1 Draghi F, Ferrozzi G, Urciuoli L, Bortolotto C, Bianchi S. Hoffa's fat pad abnormalities, knee pain and magnetic resonance imaging in daily practice. Insights Imaging 2016; 7 (03) 373-383
  • 2 von Engelhardt LV, Tokmakidis E, Lahner M. , et al. Hoffa's fat pad impingement treated arthroscopically: related findings on preoperative MRI in a case series of 62 patients. Arch Orthop Trauma Surg 2010; 130 (08) 1041-1051
  • 3 Wei W, Rudjito E, Fahy N. , et al. The infrapatellar fat pad from diseased joints inhibits chondrogenesis of mesenchymal stem cells. Eur Cell Mater 2015; 30: 303-314
  • 4 Bastiaansen-Jenniskens YM, Clockaerts S, Feijt C. , et al. Infrapatellar fat pad of patients with end-stage osteoarthritis inhibits catabolic mediators in cartilage. Ann Rheum Dis 2012; 71 (02) 288-294
  • 5 Han W, Cai S, Liu Z. , et al. Infrapatellar fat pad in the knee: is local fat good or bad for knee osteoarthritis?. Arthritis Res Ther 2014; 16 (04) R145
  • 6 Ioan-Facsinay A, Kloppenburg M. An emerging player in knee osteoarthritis: the infrapatellar fat pad. Arthritis Res Ther 2013; 15 (06) 225
  • 7 Bohnsack M, Hurschler C, Demirtas T, Rühmann O, Stukenborg-Colsman C, Wirth C-J. Infrapatellar fat pad pressure and volume changes of the anterior compartment during knee motion: possible clinical consequences to the anterior knee pain syndrome. Knee Surg Sports Traumatol Arthrosc 2005; 13 (02) 135-141
  • 8 Teichtahl AJ, Wulidasari E, Brady SRE. , et al. A large infrapatellar fat pad protects against knee pain and lateral tibial cartilage volume loss. Arthritis Res Ther 2015; 17: 318
  • 9 Duran S, Aksahin E, Kocadal O, Aktekin CN, Hapa O, Gencturk ZB. Effects of body mass index, infrapatellar fat pad volume and age on patellar cartilage defect. Acta Orthop Belg 2015; 81 (01) 41-46
  • 10 Cai J, Xu J, Wang K. , et al. Association between infrapatellar fat pad volume and knee structural changes in patients with knee osteoarthritis. J Rheumatol 2015; 42 (10) 1878-1884
  • 11 Hoffa A. The influence of the adipose tissue with regard to the pathology of the knee joint. JAMA 1904; 43 (12) 795-796
  • 12 Dragoo JL, Johnson C, McConnell J. Evaluation and treatment of disorders of the infrapatellar fat pad. Sports Med 2012; 42 (01) 51-67
  • 13 Keser S, Bayar A, Numanoğlu G. An unusual cause for anterior knee pain: strangulated intra-articular lipoma. Knee Surg Sports Traumatol Arthrosc 2005; 13 (07) 585-588
  • 14 Emad Y, Ragab Y. Liposynovitis prepatellaris in athletic runner (Hoffa's syndrome): case report and review of the literature. Clin Rheumatol 2007; 26 (07) 1201-1203
  • 15 Mathieu L, Chetouani M, Janku D, Vandenbussche E, Augereau B. Posttraumatic dislodgement of the infrapatellar fat pad: an unusual type of superolateral impingement. Orthop Traumatol Surg Res 2011; 97 (07) 776-778
  • 16 Larbi A, Cyteval C, Hamoui M. , et al. Hoffa's disease: a report on 5 cases. Diagn Interv Imaging 2014; 95 (11) 1079-1084
  • 17 Ghate SD, Deokar BN, Samant AV, Kale SP. Tumor like swellings arising from Hoffa's fat pad: a report of three patients. Indian J Orthop 2012; 46 (03) 364-368
  • 18 Krebs VE, Parker RD. Arthroscopic resection of an extrasynovial ossifying chondroma of the infrapatellar fat pad: end-stage Hoffa's disease?. Arthroscopy 1994; 10 (03) 301-304
  • 19 Turhan E, Doral MN, Atay AO, Demirel M. A giant extrasynovial osteochondroma in the infrapatellar fat pad: end stage Hoffa's disease. Arch Orthop Trauma Surg 2008; 128 (05) 515-519
  • 20 Park JH, Park JH, Lee AH, Lee DH. An unusual presentation of Hoffa's disease in an elderly patient with no trauma history: a case report. Acta Orthop Traumatol Turc 2011; 45 (03) 195-199
  • 21 Radu A, Discepola F, Volesky M, Munk PL, Le H. Posterior Hoffa's fat pad impingement secondary to a thickened infrapatellar plica: a case report and review of the literature. J Radiol Case Rep 2015; 9 (03) 20-26
  • 22 Maljanovič M, Ristič V, Rasovič P, Matijevič R, Milankov V. Solitary synovial chondromatosis as a cause of Hoffa's fat pad impingement. Med Pregl 2015; 68 (1-2): 49-52
  • 23 Ogilvie-Harris DJ, Giddens J. Hoffa's disease: arthroscopic resection of the infrapatellar fat pad. Arthroscopy 1994; 10 (02) 184-187
  • 24 Kumar D, Alvand A, Beacon JP. Impingement of infrapatellar fat pad (Hoffa's disease): results of high-portal arthroscopic resection. Arthroscopy 2007; 23 (11) 1180-1186.e1
  • 25 House CV, Connell DA. Therapeutic ablation of the infrapatellar fat pad under ultrasound guidance: a pilot study. Clin Radiol 2007; 62 (12) 1198-1201
  • 26 De Smet AA, Davis KW, Dahab KS, Blankenbaker DG, del Rio AM, Bernhardt DT. Is there an association between superolateral Hoffa fat pad edema on MRI and clinical evidence of fat pad impingement?. AJR Am J Roentgenol 2012; 199 (05) 1099-1104
  • 27 Lysholm J, Gillquist J. Evaluation of knee ligament surgery results with special emphasis on use of a scoring scale. Am J Sports Med 1982; 10 (03) 150-154
  • 28 Tegner Y, Lysholm J. Rating systems in the evaluation of knee ligament injuries. Clin Orthop Relat Res 1985; (198) 43-49
  • 29 Noyes FR, Barber SD, Mooar LA. A rationale for assessing sports activity levels and limitations in knee disorders. Clin Orthop Relat Res 1989; (246) 238-249