346 THE MUSCULAR SYSTEM. 
trochanter of the femur to the linea aspera, and to the upper fourth of the linea 
aspera itself. 
The adductor brevis is the central muscle of the adductor group. It is almost 
wholly concealed by the pectineus and adductor longus. It rests upon the 
adductor magnus; at its upper border is the obturator externus, separated from 
it by the internal circumflex artery; at the lower border is the adductor longus, 
separated by the deep femoral artery. It separates the superficial and deep parts 
of the obturator nerve in their course down the thigh. 
Obturator nerve Sacrum 
PYRIFORMIS 
/ GLUTEUS MAXIMUS 
Pubis 
AY | Pelvic fascia 
oN 
Deep branch ATWAS = 
iq 
| 
Descending muscular branches—]q7_ 12 
aia |e) V4 
PSOAS MAGNUS 
We OBTURATOR INTERNUS 
Branch to hip-j¢ 
OBTURATOR EXTERNUS 
Superficial branch Ischium 
Ane Ui cat branch to digital fossa 
: 1 // of femur 
{____QUADRATUS FEMORIS 
= 7, aa circumflex artery 
al’ Bi Descending muscular branches 
Ascending branch to obturator 
externas | 
Internal circuinflex _ 
ADDUCTOR LONGUS ADDUCTOR MAGNUS 
ADDUCTOR BREVIS 
Branch to knee-joint 
7 \ 
Branch to femoral artery GRACILIS 
Fic. 254.—ScHEME OF THE COURSE AND DISTRIBUTION OF THE OBTURATOR NERVE. 
The adductor magnus, the largest of the adductor group, is a roughly tri- 
angular muscle arising by a curved origin from the lower part of the outer border of 
the ischial tuberosity and the edge of the pubic arch, its most anterior fibres arising 
between the obturator externus and adductor brevis. Its upper fibres are directed 
horizontally outwards from the pubis towards the upper part of the femur; the 
lowest fibres are directed downwards from the ischial tuberosity to the internal 
condyle of the femur; while the intermediate fibres radiate obliquely outwards and 
downwards. The muscle is inserted (1) into the space below the insertion of 
the quadratus femoris, above the linea aspera; (2) into the whole length of the 
linea aspera; (3) into the internal supracondyloid ridge of the femur; and (4) 
into the internal condyle of the femur. The part of the muscle attached to the 
space above the linea aspera is often separated from the rest as the adductor 
minimus. The attachment of the muscle into the supracondyloid ridge is inter- 
rupted for the passage of the femoral vessels to the popliteal space. The attachment 
to the internal condyle is by means of a strong tendon which receives the fibres 
arising from the ischium (the part of the muscle associated with the hamstring 
group). This tendon is closely connected with the internal lateral ligament of the 
knee-joint. 
The adductor magnus intervenes between the other adductor muscles in front 
and the hamstring muscles behind. It is concealed anteriorly by the pectineus, 
