Procedures - Disc replacement
Dr. Fabien Bitan has been one of the lead investigators of the FDA trial of the Charite Disc replacement. He has worked with this technology since the 1980s, during his training in France where he studied with Dr. Thierry David. He has had more than one hundred cases of simple and complex reconstructive disc replacements.
Previous European Experience
Decades after Orthopedic Surgeons have given up arthrodesis (fusion) in most cases of hip or knee arthritis, we still perform spinal fusions for degenerative arthritis of the spine. Impressed by the results of hips and knees, it has been the dream of many orthopedic surgeons involved in spine care to develop a "spine replacement". Unfortunately this has been a major challenge and despite several attempts we are still far from the universality of hip replacements. These attempts have essentially helped in understanding the complexity of the enterprise. The Link SB Charite Intervertebral Prosthesis, designed in Europe, has had the most extensive experience in the world over the last 15 years.
Lumbar Spinal Degenerative Disease when unresponsive to conservative treatment, might be treated surgically. Strategies include different combinations of disk excision, nerves decompression, and fusion (with or without internal fixation). Disk excision alone exposes to the risk of discogenic back pain, while decompression might lead to instability. Fusion is the usual response to these unfortunate outcomes. But fusions have their own share of complications: graft donor site problems (most often on the pelvis), failure of healing of the bone graft and adjacent disk deterioration. Internal fixation (IF) has become increasingly popular yielding higher rates of successful fusions. But IF popularity has been darkened by its own complications: breakage (usually related to a failure of fusion), neurological damage, and osteoporosis. The rigidity of the instrumentations probably also increases the risk of adjacent disk wear.
Disk Replacement could stand as one of the important breakthroughs in spinal surgery for the future, provided ongoing prospective studies confirm its efficiency and safety.
Several prototypes have been experimented in the past. The most extensive experience has been with the Link SB III Prosthesis. The SB III has been used in Europe and more recently in most continents over the last ten years. Close to 2500 devices at this date have been implanted. Several studies have been published reporting the results.
The rational of such a concept seems obvious: restoring normal function and normal range of motion.
The Prosthesis is a three-part device: a polyethylene spacer is inserted between two metal endplates. Several sizes of endplates are available to accommodate the vertebra dimensions.
Dr Thierry David
Dr Jean Phillipe Lemaire And Dr Fabien Bitan
Dr. David's (photo top left) experience from France is of 270 disks implanted in 250 patients. David published his first 10 patients with a 10-year follow-up. Three of them needed another operation due to the lack of experience at this time. In other patients there was no wear of the adjacent disks, on MRIs done at 10 years follow-up.
Dr. Lemaire (photo bottom left), with an experience of 150 patients, reported his first 100 cases with an average follow-up of 8 years. 87% of his patients returned to work (60% at the same level of activity).
Zeegers, with his experience of 450 cases, helped in defining the indications for this technique: a young patient with good bone stock and none or mild facet arthritis. The disk involved has to be studied with an MRI and a discogram. The main complaints should be back pain, which eliminates cases of severe spinal stenosis, and acute nerve compression by a herniated nucleus pulposus.
Shelokov from Dallas published an independent evaluation of 67 patients (91 prosthesis) operated in France and Germany. The mean age was 42 YO and the average follow-up was 6 years (16 to 119 months).
A prospective randomized study has been launched in Europe: RESORD (Multicentric Randomized European Study on Replacement of the Disk) with 180 patients within 7 centers over 2 years.
Post-operative Physical Therapy Protocol
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