THE REGION OF THE KNEE 



453 



alar folds (ligamenta alarm). An extra-synovial but intra- 

 capsular pad of fat lies behind the ligamentum patellae,, and the 

 portion of it which is carried in between the two layers of the 

 patellar synovial fold (Fig. 131) is frequently the site of hyper- 

 trophy (lipoma arborescens). In this condition grape -like 

 pieces may become detached and constitute loose bodies within 



Supra-patellar bursa 

 Quadriceps tendon 



Distal epiphyseal line 



of femur 



Anterior cruciate lig. 



Oblique popliteal lig. 



Proximal epiphysea 

 line of tibia 



Prepatellar bursa 



Infra-patellar pad of fat 

 atellar synovial fold 

 ^Ligamentum patellae 



Deep infra-patellar bursa 



Subcutaneous infra-patellar 

 bursa 



FIG. 131. Sagittal Section through the Knee-joint. 



Light blue = articular cartilage. Green periosteum. 



Striped blue = tendons and ligaments. Red = synovial membrane. 



the joint. Similar hypertrophy may affect the pad of fat which 

 intervenes between the femur and the supra-patellar bursa 



(Fig. 131). 



Both the femoral and the tibial surfaces of the menisci 

 (semilunar cartilages) are covered by the synovial membrane 

 (Fig. 132) which helps to attach their peripheral margins to 

 the tibia (coronary ligaments). 



In the posterior part of the joint the synovial membrane is 

 drawn off the central part of the posterior ligament by the 



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