Interpedicular height as a predictor of radicular pain in adult degenerative scoliosis

Abstract

Background Context Spine surgeons must correlate clinical presentation with radiographic findings in a patient-tailored approach. Despite the prevalence of adult degenerative scoliosis (ADS), there are few radiographic markers to predict presence of radiculopathy. Emerging data suggest that spondylolisthesis, obliquity, foraminal stenosis and curve concavity may be associated with radiculopathy in ADS. Purpose The purpose of this study was to determine if radicular pain in ADS is associated with reduced interpedicular heights (IPHs) as measured on routine radiographs. Study Design/Setting Retrospective case-controlled study. Patient Sample The authors carried out a retrospective chart review at a tertiary care referral center that included ADS patients referred to scoliosis surgeons between 2012 and 2014. Inclusion criteria included patients with ADS and no prior thoraco-lumbar surgery. Data were collected from initial spine surgeon clinic notes and radiographs. Outcome Measures Clinical outcome data included presence, side(s) and level(s) of radicular pain; presence of motor deficits; and presence of sensory deficits. Methods Variables included age, gender, Scoliosis Research Society-30 (SRS-30) and Oswestry Disability Index (ODI) questionnaire data, and radiographic measurements. Radiographic measurements included Cobb angles and L1 to S1 IPHs on upright and supine radiographs. Associations between variables and outcome measures were assessed with univariate and multivariate statistical analyses. Authors have no conflicts of interests relevant to this study. Results A total of 200 patients with an average age of 51 years met the inclusion criteria. 60/200 presented with radicular pain. Increased age was associated with radicular pain, weakness and sensory deficits. Patients that were 55 years or older were approximately 8 times more likely to have a radicular pain (OR = 7.96, 95% CI 3.73, 17.0; p <0.001), 5 times more likely to have a motor deficit (OR = 5, 95% CI 2.55, 9.79; p <0.001), and 5 times more likely to have a sensory deficit (OR = 5.2, 95% CI 2.65, 10.2; p <0.001) than those younger than 55. More caudally-located nerve roots are more likely to develop radicular pain (p <0.001). Motor deficits were associated with worse SRS-30 functional (p=0.02) and ODI scores (p=0.005), but radicular pain and sensory deficits were not associated with lower SRS-30/ODI scores. Ipsilateral and same-level radicular pain were associated with reduced IPH in supine radiographs (p=0.002 and p=0.0002, respectively). Finally, reduced IPH on upright radiographs was associated with side- and level-specific radicular pain (p = 0.04). Conclusion Radicular pain in ADS patients is associated with reduced IPHs and increased age. Measuring IPHs on routine radiographs may be helpful in associating clinical radiculopathy with radiographic measures to guide patient management and surgical planning.

Minimally invasive transforaminal lumbar interbody fusion with expandable versus static interbody devices: radiographic assessment of sagittal segmental and pelvic parameters

“…To quantify foraminal height, the interpedicular distance was measured as previously described. 6 Index-level segmental lordosis (i.e., fused segment angle) was measured as the Cobb angle of the superior and inferior endplates at the TLIF level. Lumbar lordosis was measured as the lateral Cobb angle from the superior endplate of L-1 to the superior endplate of S-1.…”

“…A reduced or collapsed disc and foraminal height are associated with radicular symptoms, pain, and disability. 6,21 Few studies have evaluated the effects of MIS-TLIF on restoring disc height, and these studies have shown variable results. 8,10 For deformity surgery, restoring pelvic incidence-lumbar lordosis mismatch to less than 10° had a great impact on improving clinical performance scores.…”

Correlation between multifidus muscle atrophy, spinopelvic parameters, and severity of deformity in patients with adult degenerative scoliosis: the parallelogram effect of LMA on the diagonal through the apical vertebra

“…R 2 value of multiple linear regression analysis of LMA and CVA was very low in our study, which indicated that LMA could not accurately predict CVA. This might be explained by the effects of various factors on CVA [27].…”

Posterior column osteotomy plus unilateral cage strutting for correction of lumbosacral fractional curve in degenerative lumbar scoliosis

“…Compensatory curve at the lumbosacral region below the major curve is named the fractional curve; the nerve roots on the concave side of the fractional curve are the most frequent radicular pain generators in DLS patients [ 3 – 5 ]. The neurologic symptoms derived from the nerve root compression is strongly correlated with the decision to pursue surgical treatment; spine surgeons must include in surgical planning the symptomatic radicular levels that are related to the fractional curve instead of the major curve [ 6 ]. It has been recommended that all fractional curves greater than 15° must be corrected and included within the instrumentation [ 7 ].…”