Patients with radiculopathy have worse baseline disability and greater improvements following anterior cervical discectomy and fusion compared to patients with myelopathy

BACKGROUND CONTEXTAnterior cervical discectomy and fusion (ACDF) is commonly performed in patients with radiculopathy and myelopathy. Although the goal of surgery in patients with radiculopathy is to improve function and reduce pain, patients with myelopathy undergo surgery to halt disease progression. Although the expectations between these preoperative diagnoses are generally understood to be disparate by spine surgeons, there is limited literature demonstrating their discordant outcomes.PURPOSETo compare improvements in patient reported outcome measures (PROMs) for patients undergoing ACDF for myelopathy or radiculopathy. Secondarily, we analyzed the proportion of patients who attain the minimum clinically important difference (MCID) postoperatively using thresholds derived from radiculopathy, myelopathy, and mixed cohort studies.STUDY DESIGN/SETTINGSingle institution retrospective cohort studyPATIENT SAMPLEPatients undergoing primary, elective ACDF with a preoperative diagnosis of radiculopathy or myelopathy and a complete set of preoperative and one-year postoperative PROMs.OUTCOME MEASURESOutcome measures included the following PROMs: Short-Form 12 Physical Component (PCS-12) and Mental Component (MCS-12) scores, the Visual Analog Scale (VAS) Arm score, and the Neck Disability Index (NDI). Hospital readmissions and revision surgery were also collected and evaluated.METHODSPatients undergoing an ACDF from 2014 to 2020 were identified and grouped based on preoperative diagnosis (radiculopathy or myelopathy). We utilized “general MCID” thresholds from a cohort of patients with degenerative spine conditions, and “specific MCID” thresholds generated from cohorts of patients with myelopathy or radiculopathy, respectively. Multivariate linear regressions were performed for delta (?) PROMs and multivariate logistic regressions were performed for both general and specific MCID improvements.RESULTSA total of 798 patients met inclusion criteria. Patients with myelopathy had better baseline function and arm pain (MCS-12: 49.6 vs 47.6, p=.018; VAS Arm: 3.94 vs 6.02, p<.001; and NDI: 34.1 vs 41.9, p<.001), were older (p<.001), had more comorbidities (p=.014), more levels fused (p<.001), and had decreased improvement in PROMs following surgery compared to patients with radiculopathy (?PCS-12: 4.76 vs 7.21, p=.006; ?VAS Arm: -1.69 vs -3.70, p<.001; and ?NDI: -11.94 vs -18.61, p<.001). On multivariate analysis, radiculopathy was an independent predictor of increased improvement in PCS-12 (β=2.10, p=.019), ?NDI (β=-5.36, p<.001), and ?VAS Arm (β=-1.93, p<.001). Radiculopathy patients were more likely to achieve general MCID improvements following surgery (NDI: Odds ratio (OR): 1.42, p=.035 and VAS Arm: OR: 2.98, p<.001), but there was no difference between patients with radiculopathy or myelopathy when using radiculopathy and myelopathy specific MCID thresholds (MCS-12: p=.113, PCS-12: p=.675, NDI: p=.108, and VAS Arm: p=.314).CONCLUSIONSPatients undergoing ACDF with myelopathy or radiculopathy represent two distinct patient populations with differing treatment indications and clinical outcomes. Compared to radiculopathy, patients with myelopathy have better baseline function, decreased improvement in PROMs, and are less likely to reach MCID using general threshold values, but there is no difference in the proportion reaching MCID when using specific threshold values.LEVEL OF EVIDENCEIRB