Patel S J, Kaplan P A, Dussault R G, Kahler D M
Department of Radiology, University of Virginia Health Sciences Center, Charlottesville 22908, USA.
AJR Am J Roentgenol. 1998 Jun;170(6):1551-5. doi: 10.2214/ajr.170.6.9609172.
The purpose of this study was to determine the prevalence and nature of a horizontal cleft in the posterior aspect of Hoffa's infrapatellar fat pad and to show pathologic processes involving this cleft.
Fifty consecutive MR imaging examinations of the knee were evaluated for the presence and appearance of a cleft in the infrapatellar fat pad. Examples of abnormalities involving the cleft were collected from additional MR studies. MR imaging, gross dissection, and histologic examination of a cadaveric knee were also performed to evaluate the anatomy and histology of the cleft.
The cleft in the infrapatellar fat pad was revealed on MR imaging in 45 of 50 knees and had a variable shape, either linear (82%), pipe-shaped (7%), or globular-shaped (11%). Joint effusion or anterior cruciate ligament tear did not affect the appearance of the cleft. The cleft was located anterior to the distal insertion of the anterior cruciate ligament on the tibia. At gross dissection of the cadaveric knee, the roof of the cleft was formed by the ligamentum mucosum (infrapatellar plica), and the cleft was lined with synovium. The prospective evaluation of additional MR imaging examinations of the knee revealed pathologic entities of the cleft such as ganglion cysts, loose bodies, nodular synovitis, and amyloid.
A horizontal cleft located in the posterior aspect of the infrapatellar fat pad is a common and normal MR imaging finding with a prevalence of 90%. The horizontal cleft is lined with synovium and its roof is formed by the ligamentum mucosum (infrapatellar plica). This cleft communicates with the knee joint. A distended cleft can form a prominent recess mimicking pathologic processes; conversely, disorders can arise in the cleft.
本研究旨在确定Hoffa髌下脂肪垫后方水平裂隙的发生率及性质，并展示涉及该裂隙的病理过程。
对连续50例膝关节磁共振成像（MR）检查评估髌下脂肪垫裂隙的存在及表现。从其他MR研究中收集涉及该裂隙异常情况的实例。还对一具尸体膝关节进行了MR成像、大体解剖及组织学检查，以评估该裂隙的解剖结构和组织学特征。
50例膝关节中有45例在MR成像上显示出髌下脂肪垫裂隙，其形状各异，呈线性（82%）、管状（7%）或球状（11%）。关节积液或前交叉韧带撕裂不影响裂隙的表现。该裂隙位于前交叉韧带在胫骨远端附着点的前方。在尸体膝关节大体解剖时，裂隙顶部由黏膜韧带（髌下皱襞）形成，裂隙内衬有滑膜。对膝关节额外MR成像检查的前瞻性评估发现了该裂隙的病理情况，如腱鞘囊肿、游离体、结节性滑膜炎和淀粉样变。
位于髌下脂肪垫后方的水平裂隙是一种常见且正常的MR成像表现，发生率为90%。该水平裂隙内衬有滑膜，其顶部由黏膜韧带（髌下皱襞）形成。此裂隙与膝关节相通。扩张的裂隙可形成类似病理过程的明显隐窝；反之，裂隙内也可出现病变。
