Evaluation and Treatment of Tandem Spinal Stenosis

In This Article

Abstract and Introduction

Abstract

Tandem spinal stenosis (TSS) refers to simultaneous narrowing of noncontiguous regions of the spinal canal, typically the cervical and lumbar region. Symptomatic TSS may be present in more than 10% of patients presenting with spinal symptoms secondary to stenosis in any one region. Clinical presentation may present challenges because of a mixture of upper and lower motor neuron lesions that can confuse and mislead the clinician. Stenosis at another level may only be detected late, when there is failure to improve after treatment, and, if not detected, can result in either poor treatment outcomes or catastrophic complications. There is no uniform agreement in the management of TSS, and the reported surgical strategies include both simultaneous and staged approaches with each having positive and negative features. This article aims to provide the reader with details on the prevalence, evaluation, and guidance in treatment strategy for TSS.

Introduction

Spinal stenosis can be simply defined as a reduction in cross-sectional area of the spinal canal. Stenosis is most often "acquired" as a result of degenerative disease of the disk, facet joints, and ligamentum flavum, leading to a reduction in spinal canal dimension, or may be "congenital" with the loss in canal dimensions present at the level of the pedicle—both can be associated with compromise of the neural elements. Although stenosis may be asymptomatic, it is most frequently encountered in the lumbar spine, classically presenting with spinal claudication and/or features of lumbar radiculopathy.

However, stenosis may also occur at any level throughout the spinal column including cervical and, less commonly, thoracic—tandem spinal stenosis (TSS) is defined as stenosis affecting two or more noncontiguous anatomic regions of the spine. Classically, TSS is considered as the one which simultaneously affects the cervical and lumbar region, but the thoracic spine can also be involved, and in rare instances, all three regions of the spine may be affected simultaneously.^[1–3]

TSS may present with a constellation of symptoms and signs that can confuse and mislead the clinician. It may be difficult to persuade a patient presenting with lumbar spine–dominant symptoms that a previously undetected cervical spinal stenosis (CSS) is a greater priority for intervention and vice versa. The aim of this review is to provide guidance for the clinician in the diagnosis and treatment of patients with TSS.

Table 1. Details From Cohort Studies Evaluating the Presence of Tandem Spinal Stenosis in Selected Cohorts
Author	Design	Number Sex Age	Salient Findings
Nagata et al⁴	MRI study	931 304 M 68.2 yr 627 F 66.9 yr	Cervical cord compression in 24.7% LSS in 30.2% TSS in 11.0% TSS more prevalent in those with developmental canal stenosis; TSS more prevalent in men and increases with age
Matsumoto et al³⁶	MRI study	94 48 M 48 ± 13.4 yr	LSS in 12.8% CSS in 13.8% Tandem spinal stenosis in 4.3%
Kong et al⁵	Retrospective review of patients with surgery for CSM	317 208 M 63.9 ± 7.6 yr	39 patients (22 M) subsequently diagnosed with LSS after surgery for CSM More likely in those with a narrower cervical canal
Adamova et al³⁷	Cross-sectional study comparing cohort of patients with known LSS and volunteers	156 96 M 65.5 yr	Cervical cord compression in 84.6% of patients with LSS; present in 57.7% of age- and gender-matched volunteers Myelopathy in 16.7% and 1.1%
Iizuka et al⁷	Retrospective analysis of patients with LSS	237 117 M 68.8 yr	21 had coexistent CSM Torg-Pavlov ratio most important predictive factor for CSM in patients with LSS
Lee et al³⁸	Retrospective study of patients with LSS	93 38 M 69.9 yr	Moderate-severe cord compression in 23.7% Positive correlation between Lumbar Stenosis Index and severity of cord compression (r = 0.54)
Kim et al¹⁹	Retrospective study of patients with LSS	101 39 M 71 yr	76.2% and 29.7% had cervical and thoracic lesions; 23.4% had cervical cord compression with or without signal change—only 9 showed mild symptoms

CSM = cervical spondylotic myelopathy, CSS = cervical spinal stenosis, F = female, LSS = lumbar spinal stenosis, M = male, TSS = tandem spinal stenosis

Table 2. Potential Clinical Scenarios Encountered That Should Prompt the Clinician to Search for Additional Level(s) of Spinal Stenosis
Potential Clinical Scenarios Suggesting TSS
History and examination consistent with CSM but the absence of UMN signs in the lower extremities	Suspect concomitant LSS
History consistent with neurogenic claudication but the presence of imbalance, bladder/bowel dysfunction, and/or compromise of fine motor tasks	Suspect concomitant proximal stenosis either cervical or thoracic
History consistent with either CSS or LSS but symptoms disproportionate to the clinical picture	Suspect noncontiguous stenosis as possible explanation

CSM = cervical spondylotic myelopathy, CSS = cervical spinal stenosis, LSS = lumbar spinal stenosis, TSS = tandem spinal stenosis; UMN = upper motor neuron

Table 3. Comparison of Symptoms and Signs Expected With Stenosis at Either the Cord/Conus or Cauda Equina Level
Level of Stenosis	Symptoms	Signs
Cord/conus	Loss of balance Loss of fine motor control/manual dexterity Bladder and/or bowel dysfunction	UMN signs Hyperreflexia Clonus Positive Babinski Myelopathy hand signs Inverted supinator/radial reflex Hoffman's test Finger escape sign Positive Romberg's test
Cauda equina	Spinal claudication Lumbar radiculopathy Bladder and/or bowel dysfunction (rare)	LMN signs Diminished or absent reflexes

LMN = lower motor neuron, UMN = upper motor neuron

Table 4. Considerations for Surgical Strategy, Either Staged or Simultaneous
Staged	Simultaneous
Elderly; frail; >60 years of age	Young; robust; <60 years of age
Comorbidities—lack of physiologic reserve or frailty may mandate that invasive procedures performed separately in a staged fashion	Comorbidities—may be desirable to avoid multiple surgeries in high-risk patients
Noncontiguous lesions, ie, cervical and lumbar	Contiguous lesions, eg, across cervicothoracic or thoracolumbar junctions
LSS symptoms may improve after cervical stenosis addressed; simultaneous surgery does not necessarily confer long-term advantage	Potential delay in functional gains if the second site of stenosis remains symptomatic
Greater surgical invasiveness, prolonged surgical time at each affected region	Use of minimally invasive techniques to reduce surgical insult