Clinical Comparison of Selective versus Nonselective Decompression for Symptomatic Tandem Stenosis of the Cervical and Thoracic Spine: A Retrospective Cohort Study

Tandem stenosis of the cervical and thoracic spine: a systematic review

BACKGROUND

Tandem spinal stenosis (TSS) is a condition characterized by the narrowing of the spinal canal in multiple segments of the spine. Predominantly observed in the cervical and lumbar regions, TSS also manifests in the conjunction of the cervical and thoracic spine. The simultaneous occurrence of cervical and thoracic spinal stenosis engenders intricate symptoms, potentially leading to missed and delayed diagnosis. Furthermore, the presence of tandem cervical and thoracic stenosis (TCTS) introduces a notable impact on the decision-making calculus of surgeons when contemplating either one-staged or two-staged surgery. Currently, there is no agreed-upon strategy for surgical intervention of TCTS in the literature.

METHODS

Medical databases in English (Pubmed, Web of Science, Embase, the Cochrane Database of Systematic Reviews) and Chinese (CNKI, Wanfang Data, VIP CMJD) were searched using Medical Subject Heading queries for the terms "tandem cervical and thoracic stenosis", "cervical stenosis AND thoracic stenosis", "tandem spinal stenosis" and "concomitant spinal stenosis" from January 1980 to March 2023. We included studies involving adult individuals with TCTS. Articles exclusively focused on disorders within a single spine region or devoid of any mention of spinal disorders were excluded.

RESULTS

Initially, a total of 1625 literatures underwent consideration for inclusion in the study. Following the elimination of the duplicates through the utilization of EndNote, and a meticulous screening process involving scrutiny of abstracts and full-texts, 23 clinical studies met the predefined inclusion criteria. Of these, 2 studies solely focused on missed diagnosis, 19 studies exclusively discussed surgical strategy for TCTS, and 2 articles evaluated both surgical strategy and missed diagnosis.

CONCLUSION

Our study revealed a missed diagnosis rate of 7.2% in TCTS, with the thoracic stenosis emerging as the predominant area susceptible to oversight. Therefore, the meticulous identification of TCTS assumes paramount significance as the inaugural step in its effective management. While both one-staged and two-staged surgeries have exhibited efficacy in addressing TCTS, the selection of the optimal surgical plan should be contingent upon the individualized circumstances of the patients.

Do Cervical Parameters Increase the Risk of Thoracic Spinal Stenosis in Patients with Cervical Spinal Stenosis?

OBJECTIVES

The diagnosis and treatment of tandem stenosis have been widely discussed. However, studies on concurrent cervical and thoracic spinal stenosis are rare in the literature. This study was aimed to investigate the risk factors for thoracic spinal stenosis (TSS) in patients with cervical spinal stenosis (CSS).

METHODS

This retrospective cohort study assessed the risk factors for TSS in 162 patients who were diagnosed with CSS. Patients were divided into TSS (n = 45) and non-TSS (n = 117) groups. We retrospectively analyzed clinical characteristics and radiographic parameters including age, gender, body mass index, ossification of the cervical posterior longitudinal ligament (OPLLc), hypertrophy of cervical ligamentum flavum (HLFc), cervical stenosis segments, and cervical sagittal parameters. Cervical sagittal parameters were measured on T2-weighted magnetic resonance imaging including C2-7 Cobb angle, cervical tilt, T1 slope, thoracic inlet angle (TIA), C2-C7 sagittal vertical axis (C2-C7), and cervical curvature.

RESULTS

Two groups showed significant differences in ossification of the cervical posterior longitudinal ligament, HLFc, cervical stenosis segments, and TIA. The receiver operating characteristic curves demonstrated that the optimal threshold for TIA was 68.25. In multivariate logistic regression analysis, OPLLc (odds ratio [OR] = 4.403, 95% confidence interval [CI] = 1.782-10.880, P = 0.001), HLFc (OR = 4.849, 95% CI = 1.995-11.782, P < 0.001), and TIA >68.25 degrees (OR = 2.555, 95% CI = 1.044-6.251, P = 0.040) were independent risk factors for TSS. Moreover, the multiindex receiver operating characteristic curve demonstrated that the area under the curve for predicted probability was 0.799 (P < 0.001).

CONCLUSIONS

Routine thoracic magnetic resonance imaging assessment is strongly recommended in CSS patients with OPLLc, HLFc, and enlarged TIA to screen for neglected but vital thoracic disease.

Current understanding of tandem spinal stenosis: epidemiology, diagnosis, and surgical strategy

Tandem spinal stenosis (TSS) is defined as the concomitant occurrence of stenosis in at least two or more distinct regions (cervical, thoracic, or lumbar) of the spine and may present with a constellation of signs and symptoms. It has four subtypes, including cervico-lumbar, cervico-thoracic, thoraco-lumbar, and cervico-thoraco-lumbar TSS. The prevalence of TSS varies depending on the different subtypes and cohorts.

The main aetiologies of TSS are spinal degenerative changes and heterotopic ossification, and patients with developmental spinal stenosis, ligament ossification, and spinal stenosis at any region are at an increased risk of developing TSS.

The diagnosis of TSS is challenging. The clinical presentation of TSS could be complex, concealed, or severe, and these features may be confusing to clinicians, resulting in an incomplete or delayed diagnosis. Additionally, a consolidated diagnostic criterion for TSS is urgently required to improve consistency across studies and form a basis for establishing treatment guidelines.

The optimal treatment option for TSS is still under debate; areas of controversies include choice of the decompression range, choice between simultaneous or staged surgical patterns, and the order of the surgeries.

The present study reviews publications on TSS, consolidates current awareness on prevalence, aetiologies, potential risk factors, diagnostic dilemmas and criteria, and surgical strategies based on TSS subtypes. This is the first review to include thoracic spinal stenosis as a candidate disorder in TSS and aims at providing the readers with a comprehensive overview of TSS.