Cervical Laminoplasty: A Novel Surgery
Cervical laminoplasty is one of the newer and novel surgical procedures done on the neck for Cervical Spondylotic Myelopathy. This surgery is performed from the back of the neck. This surgery is done in patients who have weakness due to compression of the spinal cord in the neck.
Laminoplasty is a non-fusion surgery, which means that it does not lead to restriction of movement of the neck as opposed to fusion surgeries that cause restriction of the movement of the neck. It gives excellent results in appropriately chosen patients.
Cervical Laminoplasty is performed in patients who have spinal cord compression at multiple levels in the neck. These patients may have compression of the spinal cord due to wear and tear and aging changes. Some patients may also have underlying cervical spine stenosis These patients with stenosis have a smaller diameter of the spinal canal. Patients with congenital spinal canal stenosis are at higher risk of developing spinal cord compression and its subsequent complications.
An ideal patient for laminoplasty is one who does not have any neck pain or any pain going down into the arm (cervical radiculopathy). These patients have a good contour of their neck (Cervical Lordosis) and are not found to have any gross instability of the neck.
Prior imaging of the neck and sometimes the whole spine is done before the surgical treatment is planned. X-rays, MRI, and CT scans are performed to find the right candidate as well as do good surgical planning. Occasionally, the patient may have to undergo EMG and nerve conduction study before surgery to confirm the diagnosis.
These patients usually have weakness in their legs, which manifests in the form of gait problems and imbalance. These patients may also have weakness in their hand and upper extremity. Occasionally, thereby the patients who have more weakness in their upper extremity than their lower extremity as is the presentation of central cord syndrome.
Patients who have pain in one or both upper extremities only are not a good candidate for the surgery. Also, patients who have an inflammatory disease of their neck including ankylosing spondylitis or rheumatoid arthritis are not good candidates for this type of surgery.
Patients who have weakness along with pain in one or both arm can be a candidate for the surgery along with decompression of their nerve root, which can be done at the same time.
Laminoplasty is done under general anesthesia and an endotracheal tube is passed into the patient’s windpipe to maintain the ventilation during the surgery. We also use spinal cord monitoring by the use of electrodes and monitoring the sensory and motor functions of the nerves during the surgery. This helps in knowing if something is going bad with the nerve or the spinal cord during the surgery and helps us do the procedure safely.
Patient is positioned prone on their belly on the operating table and their head is fixed. The hairs from the back of the head are shaved. The shoulders are taped to the bed. We use intraoperative imaging to confirm our levels and treatment.
The surgical incision is given in the midline on the back of the neck and the back of the spine is exposed with meticulous dissection and control of bleeding. This surgery involves opening up the spinal canal from the back thereby giving space for the spinal cord and relieving the compression from the spinal cord.
The compression is usually from the front of the spinal cord. In patients who have a good neck contour, the surgery allows the spinal cord to move back. This drifting of the spinal cord towards the back relieves it off the pressure.To open the spinal canal, the lamina of the back of the spine is cut sequentially over multiple levels on one side.
This cut is through-and-through into the spinal canal. A similar cut is made on the lamina on the other side but is not through-and-through. This allows hinging the spinous process onto another side of lamina. Once the hinging is done, the spinal canal opens on the one side.
This opening is kept in place by the use of plate and screws. Many plates and screws can be used in the fixation. This opening of the canal allows the spinal cord to drift back and relieve its pressure.
Once it is done, the spinal cord is meticulously examined and all the bleeding is controlled. If the patient has radicular pain also then foraminotomy to relieve the pressure from the nerve root can also be performed at the same time. The incision is closed.
We regularly use vancomycin antibiotic powder to prevent infection and allow good healing. Patients are put in a cervical collar for a couple of weeks for comfort
Carefully selected patients who undergo laminoplasty do well after the surgery. They recover gradually over a period of time. Occasionally, they may have to go to rehab especially if their activities are grossly limited due to their disease process. Laminoplasty allows the patient to retain and recover there range of motion.
Complications of laminoplasty surgery are usually low and similar or less than other surgery including fusion and laminectomy, the complications may include delayed wound healing, infection, worsening of the neck posture, recurrence of stenosis, loss of normal neck balance, neck pain and nerve paralysis among others.
Laminoplasties are safe surgery in appropriately chosen patients of Cervical Spondylotic Myelopathy with or without radiculopathy. This is a non-fusion technique, which allows patients to keep the movement of their neck intact. This surgery does not involve removal of excessive bone from the back thereby keeping the anatomy intact. Occasionally, this surgery can be also used as a hybrid procedure with foraminotomy or fusion at other levels or the same level.