Comparison of the French and CARDS classifications for lumbar degenerative spondylolisthesis: reliability and validity

Degenerative lumbar spondylolisthesis: review of current classifications and proposal of a novel classification system

PURPOSE

To review existing classification systems for degenerative spondylolisthesis (DS), propose a novel classification designed to better address clinically relevant radiographic and clinical features of disease, and determine the inter- and intraobserver reliability of this new system for classifying DS.

METHODS

The proposed classification system includes four components: 1) segmental dynamic instability, 2) location of spinal stenosis, 3) sagittal alignment, and 4) primary clinical presentation. To establish the reliability of this system, 12 observers graded 10 premarked test cases twice each. Kappa values were calculated to assess the inter- and intraobserver reliability for each of the four components separately.

RESULTS

Interobserver reliability for dynamic instability, location of stenosis, sagittal alignment, and clinical presentation was 0.94, 0.80, 0.87, and 1.00, respectively. Intraobserver reliability for dynamic instability, location of stenosis, sagittal alignment, and clinical presentation were 0.91, 0.88, 0.87, and 0.97, respectively.

CONCLUSION

The UCSF DS classification system provides a novel framework for assessing DS based on radiographic and clinical parameters with established implications for surgical treatment. The almost perfect interobserver and intraobserver reliability observed for all components of this system demonstrates that it is simple and easy to use. In clinical practice, this classification may allow subclassification of similar patients into groups that may benefit from distinct treatment strategies, leading to the development of algorithms to help guide selection of an optimal surgical approach. Future work will focus on the clinical validation of this system, with the goal of providing for more evidence-based, standardized approaches to treatment and improved outcomes for patients with DS.

Outcomes in Lumbar Fusion Patients Stratified by the Clinical and Radiographic Degenerative Spondylolisthesis (CARDS) Classification System

Background and objective The Meyerding classification system remains the most common classification system for spondylolisthesis based on the percentages of vertebral translation. However, the majority of patients with degenerative disease fall into Grade 1, limiting its utility in this subset of patients. The Clinical and Radiographic Degenerative Spondylolisthesis (CARDS) classification system provides a simple radiographic framework for classifying degenerative lumbar spondylolisthesis (DLS) patients by incorporating disc height, kyphosis, and anterior translation. The purpose of this study was to evaluate how clinical characteristics, treatments, and outcomes vary across different CARDS groups in patients undergoing one- or two-level lumbar fusion for DLS. Methods The patients were classified into one of the following four CARDS groups - Type A: advanced disc space collapse with no evidence of kyphosis; Type B: partially preserved disc space with less than 5.0 mm of translation; Type C: partially preserved disc space with greater than 5.0 mm of translation; and Type D: kyphotic alignment. Univariate analyses were performed to compare demographics, symptoms, clinical outcomes, and Patient-Reported Outcomes Measurement Information System (PROMIS) physical (PH) and mental health (MH) scores across groups. Results Ninety-one patients were included in the study. Based on the CARDS classification, there were three (3%) Type A patients, 25 (28%) Type B, 58 (64%) Type C, and five (5%) Type D. No significant differences in baseline demographics, symptom duration, or PROMIS scores were observed across groups. Interbody utilization varied, ranging from 19% in CARDS C (n=11) to 60% in CARDS B (n=15) and D (n=3) patients (p=0.005). Thirty-day clinical outcomes were similar across groups. At an average follow-up of 8.9 months, improvements in PROMIS PH and MH scores and rates of clinically significant improvement were similar across groups. Conclusions Based on our findings, patients undergoing lumbar fusion for DLS present with similar demographic and clinical characteristics and experience similar clinical and patient-reported outcomes when stratified using the CARDS classification system. Posterolateral fusion (PLF) can be effective for various radiographic presentations of DLS. Further research is warranted to assess the utility of CARDS in preoperative planning.

Comparison of SDSG and CARDS classifications for L5/S1 lumbar degenerative spondylolisthesis: an independent inter- and intra-observer agreement study

BACKGROUND

Lumbar degenerative spondylolisthesis (DS) has been a common disease that makes increasing patients to suffer from different degrees of low back pain and radicular symptoms. The Spinal Deformity Study Group (SDSG) and the Clinical and Radiographic Degenerative Spondylolisthesis (CARDS) systems are commonly used to classify the disease, and help to make a more detailed treatment plan. The objective of this study is to compare the reliability and reproducibility of SDSG and CARDS classifications, and to explore their clinical application value.

METHODS/DESIGN

All 117 patients with L5/S1 lumbar DS were enrolled. Five experienced spine surgeons were selected to assess DS with SDSG and CARDS systems. Kappa (K) value was used to check the coefficient consistency for multi-factor and assess the inter- and intra-observer agreement. After 12 weeks, the analysis was repeated.

RESULTS

The inter-observer reliability and intra-observer reproducibility of SDSG system were substantial with K values of 0.704 and 0.861, while those of CARDS system were substantial with values of 0.620 and 0.878.

CONCLUSION

SDSG system had better inter-observer reliability in comparison with CARDS system, and though CARDS system is more intuitive and simpler, it is more likely to produce deviations when using it. Both SDSG and CARDS systems show substantial agreement and have great significance in surgical strategy of L5/S1 lumbar DS, they can be widely used in clinical practice.