]4.50 



CLINICAL AND TOPOGRAPHICAL ANATOMY 



re ,\I^^ ?^ J-^ ^"^^ between the patella and skin, the bursa prepatellaris subcutanea 

 (fag 1167); (2) a deeper one between the ligamentum patella and the upper part of the tibia- 

 (3) between the skin and the lower part of the tuberosity of the tibia. This is not constant 



B On the medial side.— (1) One between the medial head of the gastrocnemius and medial 

 condyle, often extending between the above muscle and the semi-membranosus This is the 

 largest of the bursse about the knee-joint, and, after adult life, usually communicates with the 

 knee-joint. But, owing to the narrow communication, it is rarely possible, when the parts are 

 relaxed by flexion of the joint, to empty the cyst. For its removal a straight incision is made 

 over the most prominent part of the swelling, its neck found by drawing aside the tendons A 

 ligature IS then pushed high up around the neck, and the cyst cut away. (2) One superficial 

 to the tibial (collateral) hgament, between it and the tendon of the sartorius, gracilis, and semi 



Fig. 1167.— Vertical Section of the Knee-joint in the Antero-posterior Direction. 

 (The synovial bursa usually present above the upper synovial cul-de-sac is not shown.) 

 (The bones are somewhat drawn apart.) (After Braune.) 



M. vastus lateralis 



M. vastus inter - 

 medius 



Femur / ./ / 

 Synovial cavity 



Patella 



Prepatellar bursa 



Alar lig. 



Anterior crucial lig 



Lig. patella 



M. gastrocnemius 



M. soleus 



M. tibialis post 



tendinosus. (3) Oneibcneath the ligament, between it and the tendon of the semi-membrano- 

 sus. (4) One between the medial condyle of the tibia and the semi-membranosus. (5) One 

 between the semi-mcmbranoHus and scnii-tendinosus. Of the above bursse, the first two alone 

 are constant. 1 he second and third are often one bursa prolonged. 



C. On the lateral side.— (1) One b(>tweon the lateral head of the gastrocnemius and the 

 condyle!; (2) one superficial to the fibular collateral ligament between it and the biceps tendon; 

 (3) one under the ligament betw(;en it and the popliteus tendon; (4) one between the popliteus 

 tendon and the lateral condyle of the femur. This is usually a diverticulum from the synovial 

 merrihrane. *^ 



The following explanations may bo given of an inflamed knee-joint usually taking the 

 Hexetl pasition:— (I) By expcnniental injc.-tions. lirauiu^ found that the capacity of the synovial 

 sac reaches its maximum with a definite degree of llcxion, i. e., at an angle of twenty-five degrees. 



