Disc Arthroplasty Essay

Degenerative disc disease have been a problem for many people as this disease brings about low back pain that seems to paralyze the working force,   the middle adulthood population (Smeltzer, 2004). Not only does it bring impaired quality of life to those who suffer from it, but Arvind Kulkarni adds large health care expenses to the list of problems brought about by this disease as seen in his article entitled Prosthetic Lumbar disc replacement for degenerative disc disease. Spinal fusion, which is the medical management for degenerative disc disease, has been criticized by several doctors in the practice due to its untoward effects in the patient’s overall recovery and lifetime improvement. Specialist in the field, Christoph Siepe, identified these unpleasant effects as accelerated adjacent system degeneration, pseudarthrosis, spinal canal stenosis, and donor site morbidity. Adjacent segment degeneration, as mentioned by Peter Ullrich in his article entitled Fusion versus Artificial Disc Arthroplasty for Lumbar Degenerative Disc Disease, stated that this is the major complication of spinal fusion and the reason why most surgeons want this procedure replaced. Adjacent segment degeneration or ASD happens when mechanical stress is transferred to the adjacent segment, also mentioned by Peter Ullrich. But research showed that this procedure can be modified to show more positive results. An anterior lumbar interbody fusion showed a low occurrence of revision surgery needed, which meant low frequency of adjacent segment degeneration, all pointed out in Mr. Ullrich’s paper.   However, to achieve this outcome, Mr. Ullrich declared that there should be an improvement in patient selection and in the procedure. The patients should be those patients having degenerative disc disease in their 5th lumbar to 1st sacral segment, because there is minimal motion at this level. By doing so, he states that fusing these segments do not change the patient’s mobility as much.   But not all are satisfied of this result. Doctors and specialists are continuously making efforts to totally changing the primary medical management for degenerative disc diseases. Studies have been conducted, and several replacement procedures were approved by the FDA. Peter Ullrich stated in his paper that the total disk replacement procedure was approved for medical use by the FDA in the year 2004 using the Charite artificial disc but for only one level of the spinal vertebrae, being the L4 – L5 or the L5 – S1. This is not the first time that a total or partial disc replacement was done. The history of this procedure was mentioned in an article in a website by Spine-Health that disc nucleus replacement was done first in 1955 by David Cleveland by injecting methyl-acrylic. Ever since then, there have two other FDA approved products aside from the Charite, the website Spine-Health states that the Prodisc was approved on August 2006 and the Kineflex lumbar on June 2005.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   A total disc replacement is being described by Jose Reyna in his article, Advances in Artificial Disc Technology, as being composed of two pieces of plates made of metal that has teeth to be able to attach itself to the end plates of the vertebral bones above and below it. This means that the particular intervertebral disc that is causing pain has to be removed and replaced by an artificial disc. Several artificial discs have been developed by various manufacturers in the country and they only differ in design and composition. The Charite, as mentioned earlier, is made up of a unique sliding core with two metal alloy end plates. The Prodisc being based on spherical articulations is made up of cobalt chromium molybdenum alloy as stated in the website Spine-Health. Inventors Qi-Bin Bao and Paul Higham developed a hydrogel prosthetic nucleus made up of PVA powder and a solvent mixed together, as seen on the article, Hydrogel intervertebral disc nucleus with diminished lateral bulging. The total disc replacement procedure has its advantages and disadvantages. Even after some models being approved by the FDA, it is still being assessed thoroughly by specialists in the field. Charles Rosen and Douglas Kiester report poor results and complications in the total disc replacement procedure. As it was mentioned in their study, this procedure causes fractures, severe pain, dislocations, extrusion of the implant, facet joint degeneration, and unexplained radiculopathy. They attribute these substandard results to the fact that the center of rotation of segmented motion is erroneous. Jose Reyna Jr. also mentions several disadvantages of the procedure in his study, stating that the anterior approach to the surgery can cause injury to the aorta and the common iliac vessels, can cause retrograde ejaculation in men by injuring the superior hypogastric plexus, hemorrhage can result from the retroperitoneal approach, and infection can occur. However, he also stated some advantages, as this procedure is said to maintain range of motion in majority of the patients as a long-term outcome. There are still a lot of studies to be conducted, and patients to be experimented on. A three year study conducted by Christoph Siepe et al., entitled Clinical Results of Total Lumbar Disc Replacement With ProDisc II: Three-Year Results for Different Indications, intended to assess total disc replacement outcome in patients who actually underwent the operation. Their results showed that not all degenerative disc diseases can be treated with this medical management. The best outcome was seen in patients exhibiting degenerative disc disease condition plus soft disc herniation or nucleus pulposus prolapse. Outcome was measured against the patient’s improvement from their preoperative levels. There were inferior results from the patients who had bisegmental damages, and a higher complication rate. Also it was mentioned that the younger patients, more specifically those aged below forty exhibited better outcome than those older than forty. Technology like this is still being developed, studied and modified as we speak. What is important is that there are people out there who care and who try to make a difference, whether it is by inventing, criticizing or being the experimental person wherein these new devices will be made a reality. References Charles Rosen, Douglas Kiester, Thay Q. Lee: The Potential Biomechanical Etiology for Lumbar Disc Replacement Failures: Review of 24 Patients and the Rationale for Revision . The Internet Journal of Minimally Invasive Spinal Technology. 2007. Volume 1 Number 2. Medscape. (2002). Advance in Artificial Disc Technology. Retrieved January 22, 2008 from http://www.medscape.com/viewarticle/445057 Medscape. (2002). Clinical Results of Total Lumbar Disc Replacement With ProDisc II: Three-Year Results for Different Indications. Retrieved January 22, 2008 from http://www.medscape.com/viewarticle/542479 Neurology India. (2005). Prosthetic Lumbar disc replacement for degenerative disc disease. Retrieved January 22, 2008 from http://www.neurologyindia.com/article.asp?issn=0028-3886;year=2005;volume=53;issue=4;spage=499;epage=505;aulast=Kulkarni Neurospine. (no indicated year). Fusion versus Artificial Disc Arthroplasty for Lumbar Degenerative Disc Disease. Retrieved January 22, 2008 from http://www.neurospinewi.com/newsletters/fusionvsartificial.html Patent Storm. (1996). Hydrogel intervertebral disc nucleus with diminished lateral bulging. Retrieved January 22, 2008 from http://www.patentstorm.us/patents/5534028-fulltext.html Smeltzer, S. and Bare, B. (2004). Medical-Surgical Nursing. Philadelphia: Lippincott Williams & Wilkins. Spine-Health. (1997-2007). Lumbar artificial disc surgery for chronic back pain. Retrieved January 22, 2008 from http://www.spine-health.com/research/discupdate/artificial/artificial01.html