It is not the cut deepness that matters but the size of the cut and the amount of muscle and bone damage that occurs during the surgery. There are 3 main types of surgery traditional open surgery, minimally invasive surgery and endoscopic.
Open traditional surgery requires a large skin incision and significant muscle retraction and bone removal to reach and visualize the spine. This was the original back surgery. New procedures have been developed to avoid the long term muscle and bone damage and weakness.
Minimally invasive spine surgery (MISS) is done through a METRx tube dilating rather then retracting the muscles. The tube is placed onto the spinal lamina. Part of the lamina bone is removed to get into the spinal canal. The nerve sac and spinal nerves are retracted to find and remove the herniated disk. The procedure is similar but less destructive then open traditional surgery.
Percutanous lumbar endoscopic discectomy (PLED) is usually done from the side (posterolateral) of the spine. The disk or spinal canal is entered and the herniated disk is removed with very little to no bone removal. Patients can be awake during the procedure decreasing operative risks. Endoscopic surgery appears to have less complications and pain after surgery. Other advantages include same day surgery, quicker recovery and earlier return to work, sometimes 2 days after surgery.
I do minimally invasive and endoscopic surgeries, but have switch almost entirely over to endoscopic surgery due to the greater benefits of these procedures. Please click Treatment Options for more details on these surgeries. Good Luck!