Effect of time-restricted diet on infrapatellar fat pad in high-fat diet-induced obese rats and relevant mechanisms / 中国组织工程研究

BACKGROUND:Overweight or obesity is the most significant risk factors for knee osteoarthritis.Time-restricted diet shows an effective effect in preventing overweight or obesity.Whether infrapatellar fat pad,an important component of the knee joint,is affected by time-restricted diet and thus influences knee osteoarthritis remains unclear. OBJECTIVE:To employ a high-fat diet-induced rat model to investigate the effect of weight loss by time-restricted diet on infrapatellar fat pad,thereby providing evidence for early prevention and treatment of obesity-related knee osteoarthritis. METHODS:Fifteen male Sprague-Dawley rats were randomly divided into three groups(n=5 per group).Rats in the control group were allowed to eat at will for 24 hours and were fed the defined control diet(12%fat);rats in the high-fat diet group were allowed to eat at will for 24 hours and were fed the high-fat diet(45%fat);and rats in the high-fat diet with time-restricted diet group were fed the high-fat diet only from 9:00(2 hours after the light)to 17:00(2 hours before the dark).After 8 weeks of feeding,mDixon-Quant sequence was used to assess proton density fat fraction in the infrapatellar fat pad and subcutaneous adipose tissue in the right inguinal region.ELISA was used to quantify differences adipokine.Sirius red staining was used to evaluate changes in fibrosis of the infrapatellar fat pad.The expressions of uncoupling protein-1 in the infrapatellar fat pad and subcutaneous adipose tissue in the right inguinal region as well as leptin,adiponectin and tumor necrosis factor-α in the infrapatellar fat pad were detected by immunohistochemistry staining. RESULTS AND CONCLUSION:After 8 weeks of feeding,compared with the high-fat diet group,the body mass of rats in the control group(P=0.036)and the high-fat diet with time-restricted diet group(P=0.003)was significantly reduced.The proton density fat fraction in the infrapatellar fat pad in the high-fat diet group was significantly higher than that in the control group(P<0.001)and the high-fat diet with time-restricted diet group(P=0.004),while there was no significant difference in the proton density fat fraction of the subcutaneous adipose tissue among the three groups.The serum leptin levels of rats in the high-fat diet group were significantly higher than those in the control group(P=0.030)and the high-fat diet with time-restricted diet group(P=0.018).Compared with the high-fat diet group,the infrapatellar fat pad fibrosis characterized by Sirius red staining in the control group(P<0.001)and the time-restricted diet group(P=0.003)was significantly decreased.The expression of leptin in IFP of the high-fat diet group was significantly higher than that of the control group(P<0.001)and the high-fat diet with time-restricted diet group(P<0.001).The expression of adiponectin in the infrapatellar fat pad of the high-fat diet group was significantly lower than that of the control group(P=0.004)and the high-fat diet with time-restricted feeding group(P=0.048).However,there was no positive expression of uncoupling protein-1 in the infrapatellar fat pad and subcutaneous adipose tissue of all the three groups,and no positive expression of tumor necrosis factor-α in the infrapatellar fat pad.To conclude,time-restricted diet could retard the fibrosis of the infrapatellar fat pad,reduce the proton density fat fraction of the infrapatellar fat pad,and affect the level of adipokine in serum and infrapatellar fat pad.Time-restricted diet may become a simple and effective option for the treatment and prevention of obesity-related knee osteoarthritis.

A cross-sectional study on the correlation between MRI signal for IPFP and knee osteoarthritis / 中南大学学报(医学版)

Objective:To investigate the correlation between MRI signal for infrapatellar fat pad (IPFP) and pathological changes in knee osteoarthritis (KOA),and to analyze the role of IPFP in the development of knee osteoarthritis.Methods:A total of 114 subjects (without special knee disease) were enrolled for this study.The intensity of MRI signal for IPFP was determined by fat-suppressed proton-density-weighted turbospin-echo magnetic resonance imaging.Based on the cartilage defects and osteophytes of knee joint,the subjects were divided into a KOA group and a control group.The difference of MRI signal for IPFP between two groups was analyzed.Results:After excluding the potential confounders of age,gender and BMI,the intensity of MRI signal for IPFP was positively correlated with defections in patellar,medial femur,lateral tibial or knee joint (OR 1.333 to 2.168,P 0.006 to 0.023);the intensity of MRI signal for IPFP was also positively correlated with osteophytes in patellar,medial femur,lateral tibial or knee joint (OR 1.309 tol.781,P 0.004 to 0.046);the intensity of MR/signal for IPFP in the KOA group was significantly higher than that in the control group (P=0.028).Conclusion:The increase in the density of MRI signal for IPFP is an imaging manifestation for knee degeneration.IPFP inflammation and endocrine abnormalities may play an important role in KOA.

Imaging Evaluation of Xiaoding Ointment in the Treatment of Acute Patellar Bursitis / 中国药房

OBJECTIVE:To evaluate clinical efficacy through comparing the change of CT image in infrapatellar fat pad before and after Xiaoding ointment in the treatment of acute patellar bursitis of knee joint. METHODS:73 patients with acute patellar bur-sitis were randomly divided into observation group(39 cases)and control group(34 cases). Observation group was given Xiaoding ointment for local application,qd,7 d as a courses,3 courses in total;control group was given triamcinolone acetonide 30 mg af-ter the extraction of articular cavity effusion,once a week,totally for 3 times. All patients of two groups underwent knee CT exami-nation for observation of the infrapatellar fat pad and articular cavity effusion volume change before and after treatment. Clinical ef-ficacies were compared between 2 groups. RESULTS:CT image alterations of treatment group showed that infrapatellar fat pad den-sity were decreased,anteroposterior diameter,vertical diameter,internal to external diameter were significantly reduced. The total effective rate of treatment group was 92.31%,which was better than that of control group(88.24%),with statistical significance (P<0.05). CONCLUSIONS:Xiaoding ointment demonstrate markedly curative effects in the treatment of acute patellar bursitis, and CT image is an effective method for diagnosis of infrapatellar fat pad.

Progress of the research for infrapatellar fat pad disorder / 临床外科杂志

The infrapatellar fat pad(IFP),also known as the Hoffa's fat pad,is an intracapsular, extrasynovial structure that fills the anterior knee compartment,and is richly vascularized and innervated. It involved knee joint biomechanics,damaged cells repairing and some other processes.Factors such as trauma or operation lead to pathological changes,including fibrosis,edema,and inflammation,and finally result in disorder syndrome.IFP was discovered and named by German surgeon Albert Hoffa in 1904.It is one of the main causes of knee pain under the patellar.Clinically,it is mainly diagnosed by physical exam-ination and MRI.Treatments include physical therapy,local anesthetics,arthroscopic resection,etc.

Advance in Hoffa's Disease and Substance P Positive Nerve Fibers (review) / 中国康复理论与实践

Hoffa's disease is the clinical condition characterized by anterior knee joint pain secondary to inflammation and/or impinge-ment of the infrapatellar fat pad. The substance P positive nerve fibers rich in the infrapatellar fat pad were stimulated by the noxious stimu-li, which may associated with the pain of Hoffa's disease. The relationship between Hoffa's disease and substance P positive nerve fibers in the infrapatellar fat pad was reviewed in this paper.

A Case of Localized Tenosynovial Giant Cell Tumor in the Infrapatellar Fat Pad of the Knee

Localized giant cell tumor of the tendon sheath (GCTTS) usually occurs in extensor an tendon sheath of the fingers and toes. It has rarely been observed in the fat pad of the knee joint. We treated a case of a 2.5x3x4 cm mass arising from the infrapatellar fat pad, which presented with extension limitation and knee pain due to lateral femorotibial joint impingement. The tumor was successfully treated using arthroscopic excision with a motorized shaver. Histologic findings were diagnosed as localized GCTTS. Herein we report this case with a literature review.

A Case of a Extrasynovial Ossifying Chondrolipoangioma in the Infrapatellar Fat Pad: Advanced Stage of Hoffa's Disease

Hoffa's disease refers to inflammation, subsequent hypertrophy and impingement of the infrapatellar fat pad, and this is all triggered by acute trauma or repetitive microtrauma. Patients with Hoffa's disease manifest with anterior knee pain and functional impairment. The chronic impingement of the infrapatellar fat pad, which contains many progenitor cells, may promote fibrocartilaginous formation and osteochondral metaplasia of adipose tissue, so osteochondroma is sometimes found in patients with advanced Hoffa's disease. We report here on an ossifying chondrolipoangioma as an advanced form of Hoffa disease that occurred in the infrapatellar fat pad.

Aislamiento e identificación de células madre adultas a partir de la grasa infrapatelar de Hoffa / Isolation and identification of stem cells derived of infrapatelar fat pad

Introducción: La grasa infrapatelar de Hoffa es una inclusión infraarticular presente en la rodilla y existen evidencias que células multipotentes están presentes en tejido adiposo del humano adulto. Objetivo: El propósito de este trabajo es aislar e identificar células mesenquimales a partir de muestras de la grasa de Hoffa tomadas de pacientes a los que se les practicó cirugía de rodilla que expongan este tejido. Metodología: Una vez obtenido el consentimiento informado de un total de 12 pacientes, se obtuvo la muestra de tejido graso. La grasa fue disgregada incubándola en colagenasa en PBS a 37ºC y con agitación, luego se inactivó con suero fetal bovino, se separaron mediante centrifugación los adipocitos maduros de las células multipotentes y se obtuvieron las muestras para sembrar en medio Mesencult. Una porción de muestra fue utilizada para identificación mediante citometría de flujo y otra parte para ser coloreada con azul de metileno. Resultados y Discusión: Tanto en las tinciones con azul de metileno como en los cultivos celulares se han apreciado células con la morfología propia de una célula mesenquimal en forma de estrella y que fueron corroborados mediante citometría de flujo para los marcadores CD13, CD29, CD59 y CD105; igualmente hemos podido observar la efectividad del tratamiento enzimático. Conclusiones: En la actualidad nos encontramos consolidando los cultivos primarios para posteriormente diferenciarlos en líneas celulares específicas que puedan ser utilizadas en estudios de patologías, tales como obesidad, diabetes y trastornos articulares...

Introduction: The infrapatellar fat pad (sometimes know Hoffa's pad) is a soft tissue that lies beneath the patella (kneecap) separating it from the femoral condyle. There is evidence suggesting the presence of stem cells on adipose tissue in the adult human. Objective: The purpose of this work is to isolate and identify grown stem cells from Hoffa's fat samples obtained from patients undergoing surgeries exposing this tissue. Materials and Methods: After obtaining informed consent, the biopsy of Hoff's fat pad was obtained. The samples were incubated with collagenase and PBS a 37ºC and agitated, then it was inactivated with fetal bovine serum and centrifuged, washed twice with PBS, the pellet was resuspended and one part was cultivated on Mesencult medium the other part was used for flow cytometry and stained with methylene blue for morphologic analysis. Also before and after the enzyme digestion, the samples were added to 10% formaldehyde to evaluate the collagenase treatment. Results and analysis: The results show the effectiveness of the enzymatic treatment, the architecture of the adipose tissue was lost. The star shape stem cells morphology was appreciated with methylene blue in the cultures, it was corroborated by flow cytometry with CD13, CD29, CD59 and CD 105 markers. Conclusions: Primary cultures are consolidating, the next aim will be to obtain differentiated specific cell types that can be use in the study of obesity, diabetes and articular illnesses...

Intraarticular Ganglion cyst under Patellar Tendon: Case Report / 대한정형외과학회잡지

Intraarticular ganglion of the knee joint is a cystic mass found around cruciate ligaments in infrapatellar fat pad or under patellar tendon. The first report on intraarticular ganglion of the knee joint along with some intermittent case reports or ganglion around the cruciate ligaments were in 1924 by Caan. Ganglion under the patellar tendon or in the patellar fat pad was first reported in 1972 by Muckle and Monahan. The two cases were treated with open arthotomy and mass excision. There was been no report on ganglion under patellar tendon since then. We managed two cases of ganglion under the patellar tendon with arthroscopic debridement. After 16 months of treatment, there has no recurrence of symptom. We report two cases of ganglion under patellar tendon with the review of the literature.