As in any surgery, spine surgery also has complications attached to it, which could lead to pain, impairment or supplementary surgery. Inabilities to create enough space around spinal nerves and spinal cord and creating too much space around nerves results in spinal instability.
Spinal surgery comprises of three attributes namely decompression of neural elements, stabilizing motion and balance of vertebrae.
Apart from resection of herniated disc, eliminating osteophytes and curing spondylolisthesis, only arthrodesis can maintain surgical outcomes of extreme cases like scoliosis, fixation of multiple spine segments and bone fusion. However, arthrodesis is susceptible to loss of motion and has the risk of initiating junctional kyphosis and adjacent segment disease (ASD) to name a few.
Though cervical disc arthroplasy (CDA) and many equivalent approaches have proven their effectiveness compared to anterior cervical discectomy and fusion (ACDF), CDA has not proven to mitigate ASD.
When a patient browses treatment options for spinal pain, it is advisable to research the cause of pain and isolate it so that the best device and procedure to could be arrived at. One should keep in mind that no device or set of device handles all causes of pain.
Motion preservation spine surgery is gaining prominence in the past decade especially in total disc replacement in cervical and lumbar spine.
Motion preservation spine surgery or MPSS is a surgical alternative for normal surgeries which are cumbersome and time consuming. They also provide the patient with the advantage of avoiding spinal fusion, which has adverse risks of infection and pain that should be borne by patients from 4 weeks to 6 months approximately. Spinal fusion also immobilizes vertebrae to avert pain, a condition which is not affordable to bear with.
Motion preservation preserves spinal motion, diminishes need for revision surgery and doubles up recovery time. It aims to create a normal biomechanics condition which enables motion in patients and mitigate adjacent segment disc disease.
In spinal fusion, the possibilities of developing degenerative disc disease (DDD), whereas are averted in motion preservation techniques. Annular repair or nucleus replacement can postpone or prevent possibilities of spinal fusions.
Though considered as a new development in spine surgery, motion preservation techniques were previously carried out at appendicular skeleton, especially in hip and knee joint replacement. Unlike these appendicular joints, surgery in functional spinal unit is complicated as it involves interaction of disc space and two facet joints.
After cervical artificial disc replacement, the patient can gradually return to routine life, under the supervision though. While even a regular shower needs approval, physical therapy could put the patient back on feet. Neck mobility must be ensured to drive though running and other sports activities should be put on hold.
Cervical artificial disc replacement (CDR), lumbar artificial disc replacements(LDR) are two motion preservation techniques. In the lumbar spine, motion preservation is classified as anterior and posterior techniques while in cervical spine it is limited to total disc replacement.
Alternate approaches to motion preservation include total disc replacement, disc nucleus replacement, interspinous process spacers, posterior dynamic stabilization devices and facet replacement or total element replacement devices.
Prodisc C, since its inception in 1990, is developed using the ball and socket formula. Composed of three components including two cobolt chrome alloy endplates and an ultra high molecular weight polyethylene (UHMWPE) inlay, Prodisc C is validated in 125,000 device implantations.
Besides removing the diseased disc and restoring normal height, the surgery decompresses surrounding neural spaces, Prodisc C not only provides motion to the vertebrae but also enables patient function.
18 anatomical sizes based on 6 foot prints and 3 heights (5, 6 and 7 mm) enable to accurately match patient anatomy.
Other cervical discs include Mobi-C cervical disc, Medtronic Prestige LP and M6-C artificial cervical device. Such artificial disc replacements last for 7 decades with no necessity for revision.
ProDisc L is the most popular and longest studied ADR. Artificial lumbar disc replacement is usually suggested only if one or two discs in the lower spine cause back pain besides absence of joint disease and compression of nerves in the spine.
SB Charite, Maverick, Flexicore, Mobidisc are few other lumbar disc replacement where the last three are under trial. Lumbar discs are planted from the anterior in minimally invasive approach.
Interspinous process spacers like X-STOP, Wallis and DIAM, for instance, open the central canal and the opening where nerve roots come out of spinal canal in order to mitigate pain and activity limitations in spinal stenosis. The devices are advantageous to senior citizens and avert elaborate open surgery.
Posterior dynamic stabilization devices employ controlled motion in spine so that normal movement is successfully achieved. Currently, they are employed with fusion and not independently.
Facet replacement or total element replacement devices are used in degeneration of facet joints and replace the same. They replace all elements back of the spine.
Interspinous process spacers, Posterior dynamic stabilization devices and facet replacement devices are still under investigation.
The previous decade saw a dramatic development in spine surgery techniques and tools and the innovations are expected in future too.
Surgeons are excited over addressing spinal pathology sans morbidity in conventional methods. Few others feel that following convergence of cardiovascular surgery and interventional cardiology, similar events would occur among spine interventionalist and surgeons.
Amidst other technologies such as spinal medicine, new image guidance technologies, informatics and artificial intelligence, they see motion preservation technologies are on the horizon. Patients could now return home, hours after their surgery.
A drive towards minimally invasive procedures especially in lumbar spine is expected along with the hope to shorten the learning curve, fading complications and low radiation exposure to patient and surgeon.
Surgeons are also happy with the evolution in pain diagnosis. They accolade the innovation in past decade that cured chronic back or neck pain (CBNP) and assert that a clear comprehension of pain cause, helped produce solutions. The trends in diagnosis enabled physicians to pin point cause of pain to the patients within hours of their visit.