Berlin, Connor

BACKGROUND AND OBJECTIVES: There has been limited assessment between anterior cervical diskectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) on patient-reported outcome measures (PROMs) in the treatment of cervical spondylotic myelopathy. We sought to compare PROMs from two-level ACDF with single-level ACCF procedures. We evaluate these results in the context of minimum clinically important difference (MCID) thresholds, which have not been performed previously. METHODS: This retrospective analysis of prospectively collected data from the Quality Outcomes Database Spine Collaborative Research Study Group compared two-level ACDF and single-level ACCF at 3-, 12-, and 24 months postoperatively. PROMs included arm pain Numeric Rating Scale, neck pain Numeric Rating Scale, Neck Disability Index, and North American Spine Society Patient Satisfaction Index. Multivariate logistic regression was used to determine differences in perioperative outcomes, as well as the impact of two-level ACDF vs one-level ACCF on PROMs. MCID thresholds were based off previously established limits. RESULTS: Three hundred and thirty patients were included (236 ACDF, 94 ACCF), and the follow-up rate was 82% at 2 years. There was a significantly higher baseline age, American Society of Anesthesiologists grade, proportion of diabetes, osteoarthritis, ambulation dependence, and myelopathy severity in the ACCF cohort. On multivariable analysis, the ACCF group had greater average length of stay and estimated blood loss. There were no significant differences between reoperation rates or nonroutine discharge. There were similar rates of MCID achievement for PROMs at all time points. CONCLUSION: This study suggests that both ACDF and ACCF procedures for cervical spondylotic myelopathy are able to achieve similar, clinically meaningful improvements in PROMs by 2 years. Patients undergoing single-level ACCF have more estimated blood loss and longer length of stay, as well as worse baseline myelopathy. Both procedures have efficacious, durable outcomes. It is reasonable that other factors, such as radiographic characteristics and patient symptoms, may influence patient selection for ACDF vs ACCF.

OBJECTIVE Primary rod fracture after surgery for adult spinal deformity (ASD) is a leading cause of revision, with recent prospective multicenter fracture rates reported at 11%–14% by 2 years. Consequently, the addition of supplemental rods has been explored to reduce fractures. Here the authors describe their experience with a novel iliac accessory rod technique in which each accessory rod anchors to an independent iliac bolt caudally via lateral connector, and attaches to the primary rod rostrally via side-to-side connector. METHODS This retrospective, single-center case series included patients who underwent thoracolumbar/lumbar fusion for ASD between March 2019 and August 2023. Data on baseline demographics, radiographic parameters, surgical characteristics, complications, rod fracture, and revision rates were collected. Paired, 2-tailed t-tests were used to compare pre- and postoperative radiographic outcomes. Rod fracture rates were compared to prior investigations via chi-square goodness of fit testing. The technique for iliac accessory rod placement is described. RESULTS The study consisted of 82 patients (mean age 66 years, 51% female, 26% with prior fusion) with a median follow-up of 2 years (IQR 28–104 weeks). A total of 50 patients (61%) had ≥ 2-year follow-up. Each surgery involved an average of 4 posterior column osteotomies and 8 segments. Iliac accessory rods were cobalt chromium and were placed bilaterally in 87% of constructs. Postoperative alignment improved significantly in the following parameters: maximum coronal Cobb angle, fractional curve, sagittal vertical axis, lumbar lordosis, thoracic kyphosis, and pelvic incidence to lumbar lordosis mismatch (p < 0.001 for all comparisons). Of 50 patients with ≥ 2-year follow-up, rod fracture occurred in 1 (2.0%), which was incidentally found and required no intervention. The present rod fracture rate was significantly lower than the authors’ historically reported institutional rate of 21% for traditional dual-rod constructs, and the 11%–14% reported in recent prospective multicenter studies that used traditional and supplemental rod constructs (p < 0.05 for all comparisons). Reoperation occurred in 12 patients (14.6%); 7 (8.5%) for proximal junctional kyphosis and 5 (6.1%) for wound complication. CONCLUSIONS Here the authors describe their experience with a novel iliac accessory rod technique to prevent rod fracture in patients undergoing surgery for ASD. The 2-year rod fracture rate (2.0%) in this study is significantly lower than the authors’ historical dual-rod fracture rate, and other prospective multicenter investigations. Future studies with longer follow-up are needed to determine the durability of this technique.

OBJECTIVE While surgical decompression is an important treatment modality for cervical spondylotic myelopathy (CSM), it remains unclear if the severity of preoperative myelopathy status affects potential benefit from surgical intervention and when maximum postoperative improvement is expected. This investigation sought to determine if retrospective analysis of prospectively collected patient-reported outcomes (PROs) following surgery for CSM differed when stratified by preoperative myelopathy status. Secondary objectives included assessment of the minimal clinically important difference (MCID). METHODS A total of 1151 patients with CSM were prospectively enrolled from the Quality Outcomes Database at 14 US hospitals. Baseline demographics and PROs at baseline and 3 and 12 months were measured. These included the modified Japanese Orthopaedic Association (mJOA) score, Neck Disability Index (NDI), quality-adjusted life-years (QALYs) from the EQ-5D, and visual analog scale from the EQ-5D (EQ-VAS). Patients were stratified by preoperative myelopathy severity using criteria established by the AO Spine study group: mild (mJOA score 15–17), moderate (mJOA score 12–14), or severe (mJOA score < 12). Univariate analysis was used to identify demographic variables that significantly varied between myelopathy groups. Then, multivariate linear regression and linear mixed regression were used to model the effect of severity and time on PROs, respectively. RESULTS For NDI, EQ-VAS, and QALY, patients in all myelopathy cohorts achieved significant, maximal improvement at 3 months without further improvement at 12 months. For mJOA, moderate and severe myelopathy groups demonstrated significant, maximal improvement at 3 months, without further improvement at 12 months. The mild myelopathy group did not demonstrate significant change in mJOA score but did maintain and achieve higher PRO scores overall when compared with more advanced myelopathy cohorts. The MCID threshold was reached in all myelopathy cohorts at 3 months for mJOA, NDI, EQ-VAS, and QALY, with the only exception being mild myelopathy QALY at 3 months. CONCLUSIONS As assessed by statistical regression and MCID analysis, patients with cervical myelopathy experience maximal improvement in their quality of life, neck disability, myelopathy score, and overall health by 3 months after surgical decompression, regardless of their baseline myelopathy severity. An exception was seen for the mJOA score in the mild myelopathy cohort, improvement of which may have been limited by ceiling effect. The data presented here will aid surgeons in patient selection, preoperative counseling, and expected postoperative time courses.