Injuries to the lumbosacral plexus
In the same way that the brachial plexus connects the spinal cord to the upper limb, the lumbo-sacral plexus provides all the nerves to the lower limb. A complete or partial injury to the lumbo-sacral plexus therefore leaves the patient with a deficit in the sensation and/or movement in the lower limb and pain which has got the typical characteristics of burning/cramping or sometimes tingling. Movements of hip, knee, ankle, foot and toes can be affected to a different degrees up to a complete injury where the whole limb is flail and there is no control of the hip with complete paralysis of the gluteal muscles. If the gluteal muscles are still working the possibility of a lesion of the sciatic nerve proper is more likely.
The treatment and the likelihood of full recovery depends on the cause and the delay between damaging event and treatment itself. In some cases the lesion is at the level of the origin of the lumbo-sacral plexus and that means inside the spinal canal where the nerves originate. In these cases the only surgical option is reconnection of the nerves at this level. Sometimes the reconnection is performed with nerve grafts (nerves taken from other parts of the body, usually the sural nerve) directly to the femoral and sciatic nerve).