Clinical study of anterior cervical decompression assisted with microscope versus mobile microendoscopic discetomy for cervical spondylotic myelopathy / 中华骨科杂志

ABSTRACT

Objective To explore the feasibility of anterior cervical decompression assisted with the microscope and mobile microendoscopic discectomy (MMED),and to compare their clinical efficacy.Methods From May 2015 to February 2017,thirty patients with cervical spondylotic myelopathy (CSM) underwent anterior cervical decompression assisted with microscope or MMED.Among them,conventional transverse anterior cervical incisions were used,and intervertebral distractors were placed in order to complete the decompression,then the fusion and fixation procedure were conducted under direct vision,and the operative time and intraoperative blood loss were recorded.Of 30 cases,15 cases were in microscope cohort (anterior cervical discectomy and fusion,ACDF 12 cases;anterior cervical corpectomy and fusion,ACCF 3 cases),including 4 males and 11 females with a mean age of 54.00±11.10 years (range,32-71 years).Another 15 cases were in MMED cohort (ACDF 13 cases,ACCF 2 cases),including 9 males and 6 females with a mean age of 59.60± 11.10 years (range,39-73 years).Neurological and cervical function were evaluated before surgery and at the follow-up according to the Japanese Orthopaedic Association (JOA) and the neck disability index (NDI) scores,and the neurologic improvement grade (NIG) was used to evaluate the neurological function.Results Both the microscope and MMED cohort underwent decompression successfully,and the visual field was clear.No neurological symptoms became worse.For the microscope,its lens and the instrument had to be adjusted separately,whereas MMED lens could move synchronously with the instrument.It was easier for MMED to reveal the posterior edge of the vertebral body and the left and right side of the spinal canal.The operation time of the microscope cohort was 90-180 min,with an average of 124.67±36.42 min;the M MED cohort was operated for 80-130 min with an average of 110.00± 15.12 min,and there was no significant difference between the two cohorts (t=1.440,P=0.161).The intraoperative blood loss for microscope cohort was 20-200 ml,with an average of 66.00±49.11 ml;MMED cohort was 30-150 ml with an average of 60.00±35.25 ml;there was no significant difference between the two cohorts (t=0.384,P=0.704).The JOA score of the microsurgery cohort improved from 8.67±3.20 preoperatively to 15.93± 1.53 at the latest follow-up,and its difference was significant (t=8.687,P=0.000).According to NIG,neurological improvement was excellent in 12 cases and good in 3 cases,giving an excellent to good rate of 100％.NDI was reduced from 18.00％±9.75％ preoperatively to 5.93％±2.58％ at the latest follow-up,with significant difference (t=5.137,P=0.000).The JOA score in MMED cohort improved from 8.87±3.11 preoperatively to 15.53±1.69 at the latest follow-up,and its difference was significant (t=9.413,P=0.000).and Among these 15 patients,11 were excellent and 4 were good,giving an excellent-good rate 100％.NDI decreased from 17.13％± 8.00％ preoperatively to 5.80％±2.43％ at the latest follow-up,and its difference was significant (t=5.592,P=0.000).There was no significant difference in JOA (t=0.680,P=0.502),NIG (P=1.000) and NDI (t=0.146,P=0.885) between the two cohorts at the latest follow-up.Conclusion Both microscope and MMED could provide a clear and magnified field of view,which was beneficial for adequate decompression during the anterior cervical surgery to ensure better clinical results.Compare to the microscope,MMED has relatively narrow indications and steep learning curve,so the surgeon should select cases strictly.