All you need to now about Prosthetics of the Intervertebral Disc
The main indication for prosthetics of intervertebral disc is spinal hernia with nerve entrapment caused by degenerative changes of intervertebral disc. Prosthetic surgery is also prescribed in the following cases:
- osteochondrosis vertebralis;
- durable low back pain that is localized between the 12th pair of ribs and gluteal furrows;
- damage of structure of vertebral disc, loss of its height;
- narrowing of radicular foramen of the spinal cord (foraminal stenosis).
Prosthetics of intervertebral disc allows to:
- eliminate pain;
- save mobility of the spinal cord and improve life quality;
- take a long-term effect from treatment;
- restore work productivity and get back to normal lifestyle quickly;
- continue doing sports and exercising.
The structure of intervertebral disc
Modern intervertebral disc prostheses have a natural physiology and can restore spinal cord mobility in six directions, including crunching and sprain. They perfectly imitate the anatomy of the human spinal cord and possess all the necessary biochemical characteristics. In addition, their shape and material features allow you to save neighboring vertebrae and strictly fix them. That is why artificial discs are not discarded by the patient's body, and rehabilitation does not require much time.
The intervertebral disc prosthesis is made of titanium and polymers. Today, new types of bioprostheses are successfully used: their properties are close to human organic tissues. The implant has two movable loops, and its outer plates repeat the shape of the vertebrae, to which the artificial disk will fit. A movable core is placed inside the prosthesis, which allows you to move the new joint in all directions. All elements of the device repeat the functions of the fibrous ring and the pulpous nucleus of the natural intervertebral disc.
Implants of intervertebral discs: types, peculiarities, advantages
Intervertebral implants can differ depending on the material, which defines the area where the device will be used, and its advantages.
One type of prosthesis is made of cobalt-molibdenic plates covered with titanium: it ensures simple and efficient growth of prosthesis to the bone. Between the plates, a nucleus responsible for segment mobility is placed. Such devices are used for disc replacement in the neck-bone. If discs in lumbar vertebra are replaced, prostheses made of cobalt-chrome-molibdenic plates covered with titanium alloy are used. The construction of such implant is similar to the previous one.
However, this is not the only type of implants used today. Surgeons start introducing revolutionary biological prosthesis of intravertebral discs that have features maximally close to natural discs’. Such implants are made of collagen which promotes efficient growth of prosthesis into natural tissues and prevents its wearing.
Besides, modern types of intravertebral discs prostheses can be divided into three main categories:
- spherical implants – their construction reminds of a sphere placed in the hollow part of nucleus pulposus;
- mechanical implants – such prostheses consist of plates with a nucleus in the center and allow fully restoring functions of the spinal cord;
- physiological prostheses – their nucleus is made of polyurethane or hydrogel, and it restores the disc while absorbing and emitting fluid from intervertebral cavity which helps to distribute load optimally.
When this or that type of intervertebral implant is chosen, a doctor should take many factors into consideration, including the peculiarities of condition and its stage, patient’s age, physiological features, etc. For example, when intervertebral discs are replaced in men with a strong muscle frame, prostheses that save joint movement should not be used. In this case, the choice of prosthesis should be individual.
How prosthesis operation is performed?
Minimally invasive operations for disc replacement on the spinal cord are performed in two stages:
- removal of the damaged disc;
- installation of prosthesis.
Before the operation, a patient goes through analyses and diagnostics with ultrasound and MRT. The obtained data will help doctor to decide whether full or partial replacement of intravertebral disc is required, and find a suitable prosthesis.
It should be noted that prosthetics of intravertebral disc is a serious surgical invasion, because it affects nervous spinal cord. However, modern German medicine has rich experience of minimally invasive operations on the spinal cord, which allows reducing the risk of damage to minimum. The operation is performed under general anesthesia and lasts for about two hours.
During the procedure, a doctor makes a small cut (not more than 6 cm) and fully removes the intravertebral disc. If the operation is made in the cervical part of the spinal cord, the cut is made on the neck from the left side. If it’s made in the lumbar spine – the cut is made on the abdomen, between the hipbone and the navel. Such access to the spinal cord reduces the risk of damage of spinal nerves.
After that, a special construction that holds the lower part of foramen intervertebrale is installed, after which the surgeon removes vertebral osteophyte, small hernias that push on the spinal cord and nerve roots. At the final stage of the operation, optimal height of the intravertebral disc is adjusted, then the construction is removed for a prosthesis to be installed on its place. This manipulation is made with the help of a microscope only and with X-ray imaging.
Rehabilitation after intervertebral disc prosthetics is very important. After two hours of surgery, the patient is allowed (and even recommended) to move freely, even if he experiences minor postoperative pain.
Drugs for the treatment of thrombosis are prescribed before spinal surgery and when the patient goes home. A few days after the operation, an ultrasound scan is performed to make sure that the blood flow in the legs and pelvic area is normal. If there are no complications, the patient can leave the hospital after 3-4 days.
Within 1.5 months after surgery, the patient should wear a special soft bandage (all the time, except during sleep). During this period, the patient is prohibited from driving a car, motorcycle or any other vehicle.
Removal and fixation of the intervertebral disc prosthesis is monitored after a certain period of time using radiography. At the end of the rehabilitation period, all restrictions on movement are canceled, and the patient can return to his normal lifestyle and routine tasks, including playing sports, exercises, driving, physical work, etc.