The Effect of Plating on Adjacent Segments in Anterior Cervical Discectomy and Fusions in Patients with Degenerative Spine Disease: A Retrospective Cohort Study.

Introduction: Plate distance is correlated with an increased incidence of adjacent segment pathologies (ASP). However, a correct plate-to-disk distance >5 mm is often not achieved. Therefore, this study aimed to quantify the effect of short plate-to-disk distance on the development of ASP using epidemiological measures in patients with cervical degenerative spine disease undergoing single-level anterior cervical discectomy and fusion (ACDFs). Methods: Medical records of all patients with cervical degeneration undergoing single-level ACDF with plating (between January 2015 and December 2017), and a follow-up of at least 1 year, were reviewed retrospectively. Radiologic and clinical outcomes were assessed preoperatively, postoperatively, and at last follow-up. The plate-to-adjacent disk distance was measured, and epidemiological measures were calculated to quantify the risk on adjacent-level ossification development (ALOD) and adjacent segment degeneration (ASD). Results: Thirty-eight (47.5%) of the 80 patients developed ALOD, and 12 (15.0%) developed ASD after a 2-year follow-up. The incidence of ALOD was significantly lower if the plate was >5 mm away from the adjacent disk space compared to <5 mm (cranial adjacent segment, 22.5% vs. 51.3% [P=0.010] and caudal, 21.4% vs. 47.8% [P=0.029]). A correct plate-to-disk distance resulted in a relative risk reduction of 57.2% for the cranial segment and 56.0% for the caudal segment, with a number needed to treat of 4. The ASD was only observed in the cranial adjacent segments, and a correct plate-to-disk distance resulted in a relative risk reduction of 32.1% and a number needed to treat of 18. Conclusions: Only four patients need to be treated with a correct plate-to-disk distance to avoid one case of ALOD. Therefore, it is advisable to keep the plate at a distance >5 mm away from the adjacent disk.

Troubleshooting an unusual complication following intrathecal chemotherapy delivered via Ommaya catheter: A case report.

The authors report the case of a 39-year-old woman with leukemic meningitis. A right frontal Ommaya reservoir was placed for intrathecal chemotherapy. During and immediately following the first injection of chemotherapy, the patient developed an episode of nausea, emesis, frontal headache and diarrhea. These same symptoms were later elicited during a second and third administration of chemotherapy. Post-placement head computed tomography showed the tip of the catheter projecting approximately 1.5 cm inferior to the floor of the left frontal ventricle. After a revision of the Ommaya catheter due to suboptimal positioning, subsequent intrathecal chemotherapy administration was tolerated without any of the adverse symptoms previously encountered. The case documents an unusual complication arising from catheter migration in the setting of intrathecal chemotherapy and also demonstrates the value in troubleshooting Ommaya reservoir complications rather than prematurely abandoning its use in favor of lumbar puncture.