Efficacy Analysis Of Multi - Segment Cervical Disc Replacement And Its Correlation With Dredging

BackgroundCervical disc herniation (CDH) is one of the most common-seen spinal degenerative diseases, often caused by trauma or long-term overstrain resulting in cervical intervertebral disc damage, and nucleus pulposus herniation. Herniated nucleus pulposus compressed the relative spinal cord and nerves, consequently causing a series of clinical symptoms.In the early stage of cervical disc herniation, conservative therapies such as acupuncture, massage, physical therapy and medications are recommended to relieve symptoms. However, its clinical effect is limited for patients with severe cervical intervertebral disc herniation manifested with obvious compression of spinal cord or nerves by herniated cervical intervertebral disc, who need operative treatment after vain conservative therapies. Anterior cervical discectomy and fusion (ACDF) has been the preferred effective surgical procedure in treating cervical disc herniation. However, a large number of clinical trials and experimental studies have discovered that, ACDF can change the disc pressure of adjacent segments, joints kinematic mechanics and zygapophyseal joints pressures, resulting in adjacent segments degeneration.Recently, a new technology, artificial cervical disc replacement (ACDR) has developed rapidly, which provides a new approach to treat cervical disc herniation. The artificial cervical disc can replace the damaged intervertebral disc and function well, with the advantages of maintaining the movement function of damaged segments and preventing the secondary degeneration of adjacent segments. Lots of biomechanical researches and clinical trials have focused on single-segment cervical disc replacement. However, cervical disc herniation often involves two or more than two segments. And few trials explore the follow-ups of patients undergoing multi-segments cervical disc replacement.In the theory of traditional Chinese medicine (TCM), Du meridian has a close relationship with spinal cord. It runs along spinal cord inside the spine and joins the brain and kidney, spinal cord and Du meridian connect brain, viscera, meridians, as well as qi, blood and body fluid, ensuring the normal physiological function of them. The main pathological changes of CDH is that the herniated disc compressed the adjacent spinal cord or nerve root. The concept of "compression" was similar with "stasis" in TCM theory. Thus, we proposed that the key pathogenesis of CDH in TCM theory was Du meridian stasis which affected the whole course of CDH. Besides, in the clinical practice, the author found that patients with multi-segments cervical disc herniation usually have the clinical manifestations of Du meridian stasis. Hence, we hypothesized that ACDF can maintain the movement function of surgical segment, decompress spinal canal and relief the symptoms of Du meridian stasis.ObjectiveTo evaluate the radiological imaging changes, clinical effect, and its correlation with dredging Du meridian in the theory of TCM.MethodsTwenty patients undergoing Bryan multi-segments cervical disc replacement (including 14 cases of two-segments and 6 cases of three-segments cervical disc replacement) were analyzed retrospectively. The disc height of replaced and adjacent segments, range of motion (ROM) of replaced segment and cervical vertebra, TCM syndrome score of Du meridian stasis, JOA score, VAS score and Odom rating were evaluated to clinical effect of ACDF.Results1. Analysis of clinical indexesThe duration of follow-up ranged from 1 to 12 months, with the average duration of 6.5 months. The TCM syndrome score of Du meridian stasis before operation was 5.5±1.54, and increased to 7.7±1.873 months after operation (P<0.05). The TCM syndrome score of Du meridian stasis 6 months after operation increased to 9.2±1.20, representing an significant difference as compared with that 3 months after operation (P<0.05). There was no statistically significant difference between 6 and 12 months after operation (P> 0.05). The JOA score before operation was 10.55±1.57, while the postoperative JOA score increased to 12.25±1.653 months after operation (P<0.05). The JOA score 6months after operation increased to 14.25±1.45, representing an significant difference as compared with that 3 months after operation (P<0.05). There was no statistically significant difference between 6 and 12 months after operation (P> 0.05). The VAS score before operation was 5.85±1.09, which decreased to 3.7±0.923 months after operation (P< 0.05). The VAS score 6 months after operation decreased to 2.55±1.00, representing an significant difference as compared with that 3 months after operation (P<0.05). There was no statistically significant difference on VAS score between 6 and 12 months (P> 0.05). As for Odom rating,10 cases were graded to "good" level,6 to "fine" level and 4 to "fair" level respectively at all follow-ups. The patient satisfaction rate reached 100%. The results were similar at 6-month and 12-month follow-ups. There were 18 cases of pathological signs (such as Hoffmann’s sign, Babinski sign, patella clonus, ankle clonus). The positive cases decreased to 6 cases at day 7 after operation,4 cases at 6-month follow-up, and 2 cases at 12-month follow-up.2. Analysis of imaging materialsThe disc height of replaced segment at week 1 after operation increased significantly compared with that before operation (P< 0.05). There was no statistically significant difference at 3,6,12 months when compared with that at week 1 after operation (P> 0.05). No significant difference was found in the disc height of adjacent segments at all follow-ups when compared with that before operation (P> 0.05). The ROM of replaced segment and adjacent segments at week 1 after operation decreased significantly compared with that before operation (P< 0.05). However, there was no statistically significant difference at 3,6, 12 months when compared with that before operation (P> 0.05).ConclusionsBryan multi-segments cervical disc replacement represents a satisfying short-term clinical effect in treating cervical disc herniation. It can maintain the ROM and cervical lordosis, and reduce the incidence of adjacent segment degeneration. Besides, ACDF can relief the symptoms of Du meridian stasis. Thus, Bryan multi-segments cervical disc replacement is a preferred strategy for patients with multi-segments cervical disc herniation accompanied by compression of nerves or spinal cord.