ABSTRACT
BACKGROUND: Factors influencing recovery after decompression surgery for cauda equina syndrome (CES) are not completely identified. We aimed to investigate the most valuable predictors (MVPs) of poor postoperative recovery (PPR) in patients with CES and construct a nomogram for discerning those who will experience PPR. METHODS: 356 patients with CES secondary to lumbar degenerative diseases treated at *** Hospital were randomly divided into training (N=238) and validation (N=118) cohorts at a 2:1 ratio. Moreover, 92 patients from the **** Hospital composed the testing cohort. Least Absolute Shrinkage and Selection Operator regression (LASSO) was used for selecting MVPs. The nomogram was developed by integrating coefficients of MVPs in the logistic regression, and its discrimination, calibration, and clinical utility were validated in all three cohorts. RESULTS: After 3 to 5 years of follow-up, the residual rates of bladder dysfunction, bowel dysfunction, sexual dysfunction, and saddle anesthesia were 41.9%, 44.1%, 63.7%, and 29.0%, respectively. MVPs included stress urinary incontinence, overactive bladder, low stream, difficult defecation, fecal incontinence, and saddle anesthesia in order. The discriminatory ability of the nomogram was up to 0.896, 0.919, and 0.848 in the training, validation, and testing cohorts, respectively. Besides, the nomogram showed good calibration and clinical utility in all cohorts. Furthermore, the optimal cut-off value of the nomogram score for distinguishing those who will experience PPR was 148.02, above which postoperative outcomes tend to be poor. CONCLUSION: The first pre-treatment nomogram for discerning CES patients who will experience PPR was developed and validated, which will aid clinicians in clinical decision-making.
ABSTRACT
BACKGROUND: Symptoms of cauda equina syndrome (CES) secondary to degenerative lumbar spine diseases are sometimes mild and tend to be ignored by patients, resulting in delayed treatment. In addition, the long-term efficacy of surgery is unclear. OBJECTIVE: To determine the predictive factors of CES and post-operative recovery in patients with symptoms lasting > 3 months. METHODS: From January 2011 to December 2020, data of 45 patients with CES secondary to lumbar disk herniation/lumbar spinal stenosis were collected from a single center. The patients had bladder, bowel or sexual dysfunction and decreased perineal sensation that lasted for > 3 months. A 2-year post-operative follow-up was conducted to evaluate recovery outcomes, which were measured by validated self-assessment questionnaires conducted by telephone and online. RESULTS: Overall, 45 CES patients (57.8% female; mean age, 56 years) were included. The duration of pre-operative CES symptoms was 79.6 weeks (range, 13-730 weeks). The incidence of saddle anesthesia before decompression was 71.1% (n = 32), bladder dysfunction 84.4% (n = 38), bowel dysfunction 62.2% (n = 28) and sexual dysfunction 64.4% (n = 29). The overall recovery rate of CES after a 2-year follow-up was 64.4%. The rates of the residual symptoms at the last follow-up were as follows: saddle anesthesia 22.2%, bladder dysfunction 33.3%, bowel dysfunction 24.4% and sexual dysfunction 48.9%. Pre-operative saddle anesthesia, overactive bladder and sexual dysfunction were risk factors for poor prognosis after decompression. CONCLUSION: CES patients with symptoms lasting > 3 months may recover after surgery. Sexual dysfunction has a high residual rate and should not be ignored during diagnosis and treatment.
