• Transcranial Electrical Motor Evoked Potentials (tceMEP) in Anterior Cervical Discectomy and Fusion Surgery: A Comparison Study between Automated and Non-Automated Technologies

    INTRODUCTION: Spinal cord injury resulting in postoperative motor deficits is a serious complication of major spine surgery. Intraoperative electrophysiologic monitoring is performed to assess the functional integrity of the spinal cord in order to recognize and avoid injury. Motor pathways have been successfully monitored using transcranial electrical motor evoked potentials (tceMEP or MEP). A novel system offers automated intraoperative monitoring capabilities that utilize the “threshold-level” alert criteria method which provides more detailed myotome-specific responses, contrasted with the conventional “presence-or-absence” technique which uses a single supramaximal stimulus to obtain responses from one or all myotomes. The automated system then displays this feedback to the end user in a simplified form. The purpose of this study was to compare the automated system to that of conventional, non- automated technology.
  • SURGICAL RESULTS AND COMPLICATIONS OF LAMINOPLASTY FOR CERVICAL COMPRESSION MYELOPATHY IN ELDERLY PATIENTS 70 YEARS OF AGE OR OLDER

    INTRODUCTION: Radiological studies have shown that 75% of people over the age 70 years have evidence of cervical degenerative diseases, which may lead to compression myelopathy. Due to the increasing life expectancy as well as the widespread use of noninvasive imaging methods like MRI, increasing numbers of elderly patients are being presented for decompressive surgery of the cervical spine. Despite the fact, surprisingly few papers have been published with regard to the surgical treatment of cervical compression myelopathy in elderly patients, and it is still controversial whether age is associated with a poor outcome from decompressive surgery.
  • 10 SECONDS TEST (GRIP-AND-RELEASE TEST) -USEFUL NEUROLOGICAL EXAMINATION FOR CERVICAL MYELOPATHY

    INTRODUCTION: Clumsiness of the hands is one of the common symptoms in cervical spondylotic myelopathy (CSM). Crandall (1966) described these clumsy hands as “Slow stiff opening and closing of the fists”. Ono (1987) also mentioned that CSM patients could not grip and release rapidly with the fingers (grip-and release test). Therefore, we hypothesize that the number of grip-andrelease movement in a fixed time may quantitate the severity of spondylotic myelopathy objectively.
  • NEURAL INSTABILITY OF THE LOWER CERVICAL SPINE

    INTRODUCTION: Classical evaluation of the lower cervical spine in the clinic involves assessment of instability based upon extensive work by White and Panjabi[1]. Although their definition of clinical instability addresses the importance of the spine's ability to protect the neural tissue, few studies have specifically examined this role. We define neural instability as the potential for compressive injury to the spinal cord or nerve roots. Since neurologic deficits typically dictate the functional outcome of musculoskeletal injuries, it appears necessary that patient evaluation include a measure of both structural instability as well as neural instability. Examining the cervical spine from the perspective of neural instability will further improve the utility of clinical instability assessment. The purpose of this study is to examine the effect of simulated lesions on lower cervical stability using human cadaver cervical spine specimens. Structural lesions were sequentially introduced to the vertebral column and the resulting changes in neural instability quantified.
  • LOAD CARRYING CAPACITY OF THE HUMAN CERVICAL SPINE IN COMPRESSION IS INCREASED UNDER A FOLLOWER LOAD

    INTRODUCTION: The human cervical spine supports the weight of the head (≈50N) and can withstand substantial compressive loads in vivo. The compressive load approaches three times the weight of the head due to muscle co-activation forces in balancing the head in the neutral posture. Compressive load increases during flexion and extension, contact sports, and other activities of daily living, and is estimated to range from 120 N to 1200 N (1, 2). In normal individuals, the cervical spine sustains these loads without damage or instability. However, ex vivo experiments show that the osseoligametous cervical spine buckles in the frontal plane under a small vertical load of 10 N (3). In the sagittal plane, large changes in lordosis occur due to bending at small vertical load levels. This has been a limiting factor in testing a whole ligamentous cervical spine specimen under physiologic loads. For the cervical spine to sustain large compressive loads, the internal shear forces and bending moments must be small.
  • CORRECTION OF CERVICAL KYPHOSIS USING PEDICLE SCREW FIXATION SYSTEMS.

    PURPOSES: The purposes of this report are to investigate the clinical results of correction of cervical kyphosis using pedicle screw fixation and to introduce our surgical techniques. MATERIALS AND METHODS: Between 1991 and 1996, 31 patients with cervical kyphosis were treated using pedicle screw fixation. Causes of kyphosis were old cervical spinal injury in 11 patients, subaxial lesion of RA in nine, cervical spondylosis in five, postlaminectomy kyphosis in three, destructive spondyloarthlopathy in two, and old pyogenic spondylitis in one. Kyphosis caused by flesh spinal injuries or spinal tumors was excluded from this study. Pedicle screw-plates system designed for the cervical spine (CPS) was used in 25 patients.
  • ANALYSIS OF A NEW TECHNIQUE USING BICORTICAL ICBG FOLLOWING CORPECTOMY

    INTRODUCTION: Despite many proposed alternatives to autologous bone grafting for cervical reconstruction, autologous iliac crest bone grafts (ICBG) are still considered the biological and biomechanical standard. Use of tricortical ICBG, however, is a major source of post-operative morbidity. Complications include pain, nerve injury, infection, cosmetic deformity, and anterior superior iliac spine (ASIS) avulsion fracture. In an attempt to reduce this morbidity, the authors report the clinical results of a new technique using bicortical rather than tricortical ICBG in patients undergoing cervical corpectomy.
  • Reperfusion and Time-Dependent Recovery After Spinal Cord Injury

    INTRODUCTION: Residual spinal cord compression after impact occurs in the majority of patients with acute spinal cord injury. Our objectives were to determine the importance of early time-dependent spinal cord decompression on recovery of evoked potential and neurologic motor function and determine if regional blood flow changes are associated with neurologic recovery. Earlier decompression would prevent neural damage measured by histopathologic methods and MRI.