Cervical Spondylotic Myelopathy Treated by Oblique Corpectomy: A Prospective Study

In Reply: I appreciate the opportunity to clarify the points that were previously included in my commentary on the article by Drs. Kiris and Kilinçer (1). The authors maintain that their work is a prospective study. They also assert that informed consent was obtained; however, it remains unclear whether the informed consent was for surgery to be performed or for the patient to participate in a study evaluating the risks, benefits, and alternatives of a new surgical procedure. The most concerning aspect of their review is the lack of definition of the denominator of this study. To determine the generalizability of their results, it is imperative to know how often they chose to use this approach. For instance, they state that any patient with 2 mm or more of motion was excluded. How often does this occur in their study population? Did 40 of 50 patients, or 80% of those who were initially assessed, qualify for the study, or did 40 of 200 patients, or 20%, qualify? This information is needed to evaluate the study. Furthermore, to refer to 40 “consecutive” patients in this study is misleading, as there appear to have been a substantial number of patients either excluded or sent back to their referring neurosurgeon for fusion. Knowledge of this number is not able to be determined after a careful review of their published report. Lastly, it was not clear when the final x-rays were obtained for each patient. Was it at the time of the last clinical follow-up examination? If they did obtain x-rays at a mean duration of follow-up of 59 months, as their comment implies, then it would have been very easy and very valuable to have included specific data regarding the changes in sagittal alignment at late follow-up. The clear concern for a procedure such as this is that the 31 patients who were not already fused (3 were fused preoperatively, and 6 were fused postoperatively) would be at risk for late kyphotic angulation. If the authors have these data, it would have been preferable for them to have shared it with the readers who are attempting to evaluate the utility of their procedure. Robert F. Heary Newark, New Jersey