On the human body, the limbs can be divide into segments, such as the arm and the forearm of the upper limb, and the thigh and the leg of the lower limb.
If these segments are cut transversely, it is apparent that they are divided into multiple sections. These are called fascial compartments, and are formed by tough connective tissue septa.
Knowledge of these compartments not only simplifies the learning of innervation, it is also important in situations where pressure can build up in one compartment, potentially damage the contents.
This problem is called compartment syndrome and have happen acutely in a bleed (possibly caused by a fracture), or gradually, as with an athelete's overuse of a muscle.
Increased pressure within the compartment compresses the nerves, and it also decreases blood perfusion. In an acute situation it can cut off blood supply completely, leading to necrosis of the tissues in that compartment.
Compartment syndrome can be treated by a fasciotomy, where the septum enclosing the compartment is cut to relieve the pressure.
- Anterior - supplied by the femoral nerve, contains the knee extensors and hip flexors.
- Medial - supplied by the obturator nerve, contains the hip adductors.
- Posterior - supplied by the sciatic nerve, contains the knee flexors and hip extensors.
- Anterior - supplied by the deep peroneal nerve and anterior tibial artery, contains the dorsiflexors.
- Lateral - supplied by the superficial peroneal nerve, contains the evertors of the foot.
- Posterior - supplied by the tibial nerve, contains the plantar flexors.
The forearm is divided into two compartments: