Lumbar mcrodisectomy is the most common operation performed by neurosurgeons to treat leg pain / sciatica. A small incision (under an inch long) is made in the middle of the back, an opening is made into the spinal canal and part of the piece of offending disc is removed. 
Lumbar Disc Shock-absorber
Not all of the disc is removed because most of the disc is still acting as a valuable “shock-absorber” within the spine. Consultant Neurosugeon, Mr Ranjeev Bhangoo says, "The operation typically takes less than one hour. Patients should be encouraged to walk around as soon as possible after the procedure and some are even well enough to go home on the evening of the procedure, although an overnight stay is more common. Patients usually report some moderate back discomfort for the first few days after the procedure. Depending on your occupation a period of between two and six weeks off work is usually recommended."
More than 90% of patients notice an immediate relief from leg pain. In around one in 20 patients a recurrence of the herniation may occur at some point in future life. See - Neurosugery for Pain Management / Leg Pain Sciatica
Endoscopic Lumbar Microdisectomy 
This operation is now increasingly performed using keyhole surgery or 'endoscopically' - see Endoscopic Microdisectomy, As Consultant Neurosurgeon in Minimally Invasive Spinal Surgery, Mr Irfan Malik explains: Endoscopic microdiscectomy is currently deemed suitable for patients with sciatica caused by a prolapsed (slipped) disc. Whether an individual patient would benefit from this technique as opposed to conventional open surgery is a decision best made by the patient in consultation with a surgeon who is expert in the technique as various technical considerations (that vary from patient to patient) do play a significant role in the success of this technique.
