A cervical disc is a softer structure located between two bony vertebral bodies to allow movement between the two bodies.
A cervical disc prolapse is posterior dislocation of the cervical disc thereby causing compression on either the spinal cord or the nerve of the upper limb exiting from the spinal cord.
The spinal cord or exiting nerve gets damaged progressively with time due to continued compression.
Pressure on only the exiting nerve of the upper limb leads to Cervical Radiculopathy . If only the exiting nerve is compressed, the patient may present with neck pain radiating to the arm which is termed Cervical Radiculopathy
With continued severe nerve root compression, the nerve may get damaged resulting in slowly progressive numbness, weakness, loss of muscle bulk in the upper limb or rarely even sudden onset of severe weakness/loss of power in a part of the upper limb. Sudden onset of severe weakness/loss of power in a part of the upper limb does not carry a good prognosis. Therefore, it is imperative that patients undergo MRI of the cervical spine when they present with significant neck pain radiating to the upper limb to pick up significant exiting nerve root compression.
Pressure on the spinal cord leads to cervical myelopathy
Subtle symptoms may includeFor a long time, radiological and silent damage may go on occurring without symptoms. Actually, the spinal cord goes on tolerating slow progressive damage without symptoms for a long time. However, due to compression on the spinal cord, the protective layer of CSF (cerebrospinal fluid) between the bony spine and the spinal cord is lost. Therefore, many patients present with sudden weakness or even total loss of power in all 4 limbs following a minor injury to the neck whereby the bony spine hits the spinal cord directly without the cushioning effect of CSF. This can be a catastrophic presentation because neurological recovery after spinal cord injury is always unpredictable despite surgery.
Therefore, it is imperative that patients undergo MRI of the cervical spine even with subtle symptoms to pick up significant spinal cord compression.
MRI would diagnose correctly the levels, severity, location of cervical disc prolapses and the extent of compression on the spinal cord/exiting nerve root and the extent of spinal cord damage.
Surgery is done from the front of the neck through a tiny incision in a skin crease of the neck (for a good cosmetic result) via which the surgeon reaches the front of the disc space and thereafter under microscopic vision, removes all the disc material from the front to the back including the posterior part compressing the spinal cord/exiting nerve root.
After taking the pressure off the spinal cord/exiting nerve root, the surgeon has to replacethe gap in the spine thus created by disc removal. Most surgeons place a Titanium/PEEK cage filled with bone graft in the gapand thereafter fix it with screws and/or plates to the normal vertebral bodies above and below the gap created in the spine.
I prefer a PEEK cage filled with Tricalcium Phosphate with teeth on the upper and lower sides of the cage which fix it in place between the two vertebral bodies thus not requiring additional screw/plate fixation and bone graft harvest, making the surgery even more minimally-invasive. The absence of plates/screws leaves Zero artefact on postoperative MRI.
This surgery is called Anterior Cervical Microdiscectomy and Fusion because the disc gets replaced by a cage with bone graft which fuses the upper vertebral bone to the lower vertebral bone.
A trendy surgery is replacing the removed disc by an artificial disc thus retaining movement between the two vertebral bodies which was the original function of the cervical disc as given by God. That is why, this surgery is called Motion-Preserving Cervical Disc Replacement or Motion-Preserving Cervical Arthroplasty.
The patient has to wear a collar for some time following a fusion surgery to avoid aggressive neck movements.
An aggressive exercise/physiotherapy regimen is crucial to maximizing recovery post-operatively and needs to start from post-operative day 1.
Minimally Invasive Neck Surgery for Cervical Disc prolapse leads to a successful quick return to normal life. Patients with severe neck pain radiating to the upper limb have near immediate miraculous disappearance of their pain post-operatively.
Moreover, Minimally Invasive Neck surgery for Cervical Disc prolapse is almost a non-painful surgery
Recovery in patients who already have symptoms of spinal cord/nerve root damage depends on extent of symptoms, extent of spinal cord damage on pre-operative MRI and precision of surgery. Recovery will happen slowly over many months and is maximized by an aggressive exercise/physiotherapy regimen. However, the extent and time-period of recovery is unpredictable. But it must be mentioned that many patients exhibit miraculous improvement over a few months. And therefore, it is never too late to try.
Advanced symptoms such as bowel/bladder involvement and gross weakness/paralysis with wasting or loss of muscle bulk are unlikely to reverse completely. Therefore, it is imperative that patients undergo identification and surgery for this problem before developing such advanced symptoms.
There are some medications for residual symptoms such as spasticity/heaviness of the legs, paraesthesias or abnormal sensations, burning sensations, nerve pain radiating along the arms or legs.
