The Role of Stenosis Ratio in Predicting Surgical Satisfaction on Patients with Lumbar Spinal Canal Stenosis: A Receiver-Operator Characteristic (ROC) Curve Analysis

Abstract

BAckground: The aim of this study was to evaluate to elucidate independent factors to predict surgical satisfaction in lumbar spinal canal stenosis (LSCS) patients.

Materials and Methods: Patients who underwent surgery were grouped based on the age, gender, duration of symptoms, walking distance, Neurogenic Claudication Outcome Score (NCOS) and the stenosis ratio (SR) described by Lurencin. We recorded on 2-year patient satisfaction using standardized measure. The optimal cut-off point in SR, NCOS and walking distance were required for predicting surgical satisfaction from sensitivity and specificity calculations and receiver operator characteristic (ROC) curves.

Results: One hundred fifty consecutive patients (51 male, 99 female, mean age 62.4±10.9 years) were followed up for 34±13 months (range 24-49). One, two, three and four level stenosis was observed in 10.7%, 39.3%, 36.0 % and 14.0% patient, respectively. Post-surgical satisfaction was 78.5% for the 2 years follow up. In ROC curve analysis, the asymptotic significance is less than 0.05 in SR and the optimal cut-off value of SR to predict worsening surgical satisfaction was measured as more than 0.52, with 85.4% sensitivity and 77.4% specificity (AUC 0.798, 95% CI 0.73-0.90; P < 0.01).

Conclusion: The findings show that the SR could be a preferred parameter for predictable to surgical satisfaction compared to walking distance and NCOS in Iranian population into clinical practice.

 Keywords: Lumbar spinal canal stenosis, predicting, surgical satisfaction, ROC analysis, stenosis ratio