sheet no.18

Medial Compartment of lower limb :



-located between med. And post. Intermuscular septi
-it consists of 5muscles
1-gracilis
2-add. Longus
3-add. brevis
4-add. Magnus
5-obturator externus

-all supplied by obturator N. except part of the add. Magnus that is supplied by the sciatic N. (hamstring head)
-all supplied by the profunda of the femoral and obturator A.
-all originate from the pubic bone and the ischium or both, except obturator exter. That originates from the outer surface of the obturator foramen
-all inserted to the femur except gracilis into tibia
-all add. The hip joint
-all cross only one joint except gracilis that crosses two joints (hip and knee)

Add. Longus
O: pubic bone
Ins: linea aspra of femur
Add. Brevis
-It is located below add. Longus and above add. Magnus i.e. it is sandwiched between them.
- It is also sandwiched between the ant. Division of obturator N. and the post. Division of the obturator N. (both of them supply it)
O:pubic bone and ischium
Ins: linea aspra of femur
Gracilis
O:pubic bone
Ins: upper medial surface of tibia (SGS area of tibia)
Ac: it add. The hip and lat. Rotate the knee because it crosses two joints(hip and knee)

** NOTE:SGS area: it is the insertion site of 3 M. with different N. supply)
S:sartoreus (N.S. femoral N.)
G:gracilis (N.S. obturator N.)
S:semitendinosis (N.S. sciatic N.)

Add. Magnus
Deepest, largest, most powerful muscle of the add. Group M. with two nerves supply that acts as between med. Comp. and post. Comp. of the thigh and represented by its nerve supply
-It has two heads:
1st: add. Head(part)
O: from inf. Pubic ramus and ischial ramus
Isn: upper 4\5 of the med.side of linea aspran
N.S.: obturator N.
Act: it add. The hip
2nd: hamstring head(part) and also it is the post. Comp. Part(flexors of hip).
- O:ischial tubrosity ( because all hamstring muscles originate from ischial tubrosity)
- Ins: lower part of med. Side of femur which specially in an area called add. Tubercle of femur located above med. Epicondile (named so because the add. Magnus is inserted in it)
N.S.: sciatic N.
Act: add. And extend the hip

NOTE: it has 2 parts because it is located between 2 compartments , one is the med.(add.) Comp. and the other is the post.(hamstring) Comp.. therefore, it is a midway muscle between these two comp. In embryological development.


Obturator N.
- O: ant. Divisions of the ventral rami L2 , L3 , L4 of lumbar spinous nerve
-then crosses the pelvis then leave through obturator foramen below pectineus ,there it divides into ant. Division and post. Division to sandwich the add. Brevis
Branches:
1-muscular branch
2-articular branch: to hip and knee joints
3-one coetaneous branch: to skin and med. Side of the thigh.

**NOTE: pregnant ladies lay on their back flexing there knee and hip in the last weak before labor and that is to decrease the pain because baby at that time is pressing at the obturator N. by his head that is located in the pelvic inlet which is painful.


I dedicate this sheet to all my friends and to all medicine students especially;
Dana twalbeh\ basher sharma \ bashar kako \ ous samer \ fahad naji \ sahar basil \ fahaf adel \ yazan radaydeh \ omar radaideh \ yezan 3toom
Special thanks for dr. Maher al-hadidi