Choi ES, et al. Clin Orthop Surg. 2021 Mar;13(1):60-66. https://doi.org/10.4055/cios20111

To compare the clinical and radiological outcomes between patients with long posterior cervical fusion (PCF) in which fusion stopped at C7 versus patients in which fusion crossed the cervicothoracic junction (CTJ). The patients were divided into 2 groups on the basis of the lower-most instrumented vertebra (LIV); C7 group patients (n = 25) and upper thoracic (UT) group (n = 21). We analyzed the visual analogue scale of arm/neck pain, Japanese Orthopedic Association (JOA) score, and neck disability index (NDI). And we also measured the following parameters: (1) pseudomotion of fused segments; (2) C2–C7 sagittal vertical axis; (3) T1 slope; and (4) C2–C7 lordosis. Arm and neck pain were similar in both groups pre- and postoperatively. Interestingly, mean postoperative NDI score in the UT group was significant worse when compared with the C7 group (9.7±4.6 vs. 14.2±3.7, p = 0.006). Although UT patients had longer fusion levels, the fusion rates were not significantly different between the C7 and UT groups (96.0% vs. 90.5%; p = 0.577). The radiographic parameters did not show any significant differences between the groups at final follow-up. Our study demonstrates that multi-level PCF stopping at C7 does not negatively affect C7-T1 segment failure, fusion rate, neck pain, neurologic outcomes, and global sagittal alignment of the cervical spine. Hence, it is unnecessary to extend the long PCF levels caudally across the healthy CTJ for fear of development of adjacent segmental disease (ASD) at the C7-T1 segment.

Park HG, et al. Clin Orthop Surg. 2021 Dec;13(4):539-548. https://doi.org/10.4055/cios20255

Background: Objective: White cord syndrome is extremely rare and search of the literature has revealed very few cases. Postoperative MR scan revealed hyperintense intrinsic cord signal changes within cord ischemia and edema. It is thought to be caused by reperfusion injury of the spinal cord. This is called white cord syndrome. This report is very rare case of ‘White Cord Syndrome’ with paraplegia after anterior cervical discectomy and fusion (ACDF). Case presentation: A 49-year-old woman presented with neck pain lasting for several months and second and third finger radiating pain. Severe cervical herniated intervertebral disc findings could be identified at C6–7 level on C-spine MRI. ACDF C6–7 surgery was performed. Immediately after the operation, physical examination revealed paraplegia and emergency MRI was performed. On MR images, T2 high signal myelopathy suspected as reperfusion injury at C6–7 level, and emergency surgery was performed under diagnosis of white cord syndrome. After the emergency operation, the paraplegic problem was gradually resolved. Before discharge, motor power and sensory deficit of bilateral lower extremity were fully recovered. Conclusion: Surgeons should explain the possibility of white cord syndrome before cervical decompression surgery and should perform a neurological examination immediately after surgery. We recommend that the importance of early recognition and prompt treatment of white cord syndrome.

No significant differences in clinical results and union rates were found between PLIF and PLF patients. Selection of the operation technique will reflect the surgeon's preferences and patient condition.

This study aimed to analyze radiological outcomes in patients with adolescent idiopathic scoliosis (AIS) who underwent posterior correction with high-density pedicle screw-only constructs. We hypothesized that high-density pedicle screw-only constructs in AIS would provide a high correction rate and would facilitate the maintenance of the correction or obviate the loss thereof. We retrospectively analyzed radiological outcomes over a minimum follow-up period of 5 years in patients with AIS who underwent posterior correction with high-density pedicle screw-only constructs. A total of 124 consecutive patients were included. Demographic data, including age, sex, operated fusion level, numbers of screw, Lenke curve type, Risser stage, and follow-up period were retrospectively collected from electronic medical records and radiological measurements including serial follow-up. The average number of pedicle screws was 1.96/vertebra. The average curve correction was 48.3% for the proximal thoracic (PT) curve, 83.1% for the main thoracic (MT) curve, and 80.2% for the thoracolumbar/lumbar (TL/L) curve at final follow-up. Use of high-density pedicle screw-only constructs helped achieve excellent correction rates, with no significant loss of correction at final follow-up. We obtained excellent correction rates of 48.3% for PT, 83.1% for MT, and 80.2% for TL/L curves using high-density pedicle screw-only constructs in AIS, with no significant loss of correction at final follow-up.