Faculty Bibliography

STUDY DESIGN/METHODS:Retrospective Cohort Study. OBJECTIVE:To compare MI-PCF and ACDF in the treatment of unilateral cervical radiculopathy. SUMMARY OF BACKGROUND DATA/BACKGROUND:Minimally invasive posterior cervical foraminotomy (MI-PCF) has been shown to be equally effective as ACDF in treating cervical radiculopathy due to foraminal stenosis and similar pathologies. Additionally, it has been hypothesized that preserving motion and avoiding fusion reduces risk for adjacent segment disease (ASD), but potentially increases risk for subsequent revision to an ACDF. With similar short-term outcomes and substantial advantages, MI-PCF may be an effective alternative to ACDF for addressing appropriate cervical pathology. METHODS:A retrospective review was performed to identify patients between 2009-2013 who underwent ACDF or MI-PCF with a minimum follow-up of 7-years. Demographic data was recorded. Revision rates and average time to revision between cohorts were compared. Clinical outcomes were assessed at each follow-up visit with Neck Disability Index (NDI) and Visual Analog Scale for neck and arm pain (VAS-n and VAS-a) scores. All complications were reviewed. Standard binomial and categorical comparative analysis were performed. RESULTS:A total of 251 consecutive patients were included (205 ACDF, 46 MI-PCF). Mean follow-up for the ACDF and MI-PCF groups were 98.3 and 95.9 months, respectively. Complication rates were 2.9% and 2.2% for the ACDF and MI-PCF cohorts, respectively (p = 0.779). Revision rates were 7.8% for the ACDF cohort and 8.7% for the MI-PCF cohort (p = 0.840). Both cohorts experienced significant improvements in their clinical scores compared to their preoperative values. Final VAS-n (ACDF: 2.6; MI-PCF: 1.6) and VAS-a (ACDF: 1.1; MI-PCF: 0.4) scores differed significantly at final follow-up (p =  < 0.001; p =  < 0.001). CONCLUSION/CONCLUSIONS:MI-PCF is a safe and effective alternative to ACDF in the treatment of cervical radiculopathy, demonstrating substantial benefit. After final follow-up, MI-PCF demonstrated superior improvements in VAS scores, without increased complication or revision rates.Level of Evidence: 3.

BACKGROUND CONTEXT/BACKGROUND:Although highlighted in joint arthroplasty studies, long-term outcomes between differing biomaterial composites, such as metal-on-metal (MoM) and metal-on-plastic (MoP) in anterior cervical disc replacement (ACDR) have not been thoroughly investigated. PURPOSE/OBJECTIVE:The purpose of this study was to evaluate the patient-reported clinical outcomes, overall reoperation rates, complications, and rates of ASD of MoM versus MoP artificial discs in two-level ACDR for the treatment of cervical DDD. STUDY DESIGN/SETTING/METHODS:Meta-analysis and systematic review PATIENT SAMPLE: 980 patients (442 MoM, 538 MoP) across 7 studies OUTCOME MEASURES: Patient reported clinical outcomes (NDI, VAS-n, VAS-a), overall reoperation rates, complications and rates of ASD METHODS: A systematic search strategy of three electronic databases (PubMed, CINAHL Plus, and SCOPUS) was conducted utilizing terms related to two-level ACDR. All studies included had a sample size of >10 patients, had a minimum 5-year follow-up, and reported data on adjacent segment disease. Cadaver studies, non-English manuscripts, articles with less than 5-year follow-up and studies in which only single-level ACDR was investigated were excluded. A total of 7 studies were included in this analysis. Studies were analyzed for demographic data, clinical outcome scores (NDI, VAS-neck, and VAS-arm), overall reoperation rates, complications, and rates of ASD. A random-effects model of meta-analysis was used for groups that were determined to be heterogenous and a fixed-effects model was utilized for groups that were not. An overlap of 95% confidence intervals suggests no statistically significant difference at the p<0.05 level. RESULTS:Seven studies were included with data on 980 patients (442 MoM, 538 MoP). The study population was 52.84% female, with a mean age of 48.01 years, and a mean follow-up of 85.66 months. The mean improvement in NDI was 34.42 (95% CI, 32.49-36.36) and 29.72 (95% CI, 27.15-32.29) for the MoM and MoP groups, respectively. The mean improvement in VAS-neck was 11.20 (95% CI, 10.69-11.70) and 8.78 (95% CI, 7.81-9.74) for the MoM and MoP groups, respectively. The mean improvement in VAS-arm was 10.73 (95% CI, 9.83-11.63) and 8.49 (95% CI, 7.59-9.39) for the MoM and MoP groups, respectively. 3.85% (95% CI, 2.40-6.10) of patients who underwent ACDR with a MoM implant required reoperation compared to 5.33% (95% CI, 3.68-7.65) of patients with a MoP implant. Heterotopic ossification and dysphagia were the most common complications in both groups. The MoM cohort showed a higher incidence of HO (72.62% vs. 21.07%), but a lower incidence of dysphagia (0.96% vs 16.31%) compared to the MoP cohort. The MoM cohort had a larger proportion of patients with ASD who underwent subsequent surgery at an adjacent level (7.89% MoM versus 1.91% MoP). CONCLUSIONS:Our present meta-analysis suggests that the use of MoM artificial discs in two-level ACDR results in superior clinical outcome score improvement, but higher rates of ASD requiring secondary surgery compared to MoP discs after a follow-up period of 5 years or more.

BACKGROUND CONTEXT/BACKGROUND:Obese patients can pose significant challenges to spine surgeons in lumbar fusion procedures. The increased risk of complications has led surgeons to be wary in pursing operative interventions in these patients. Since the advent of minimally-invasive techniques in lumbar fusion, surgeons are turning to these procedures in an attempt to minimize operative time, blood loss and overall cost. With an increased proportion of obese patients in the population, it is imperative to understand the long-term outcomes in these minimally-invasive approaches. PURPOSE/OBJECTIVE:The purpose of this study was to evaluate the long-term safety and efficacy of extreme lateral interbody fusion (XLIF) in the obese. STUDY DESIGN/SETTING/METHODS:Retrospective Cohort Study. PATIENT SAMPLE/METHODS:115 patients (53 non-obese and 62 obese) who underwent XLIF with a minimum of 5-year follow-up. OUTCOME MEASURES/METHODS:). Functional outcomes were assessed by comparing pre- and postoperative VAS and ODI scores. Reoperation rates were compared between cohorts. PI-LL mismatch was calculated from both pre- and postoperative radiographs. Rates of graft subsidence and fusion were measured at final follow-up. RESULTS:115 consecutive patients were included (53 non-obese & 62 obese) with a mean follow up of 95.3 months. Mean BMI was 25.3 in the non-obese group and 35.3 in the obese group (p<0.001). There were more females in non-obese cohort. VAS scores decreased by a mean of 5.7 in the non-obese cohort, and 5.4 in the obese cohort (p=0.213). ODI improvement was also similar between the groups. 5.6% of non-obese patients required reoperation compared to 9.6% of obese patients (p=0.503). Graft subsidence rates at final follow-up were 5.66% and 8.06% for the non-obese and obese groups, respectively (p= 0.613). Rates of successful fusion were 96.23% and 98.39% for the non-obese and obese groups, respectively (p= 0.469). Both cohorts achieved a similar proportion of PI-LL mismatch correction, 85% in obese vs 78% in non-obese patients (p=0.526). CONCLUSION/CONCLUSIONS:Obese patients have similar surgical outcomes to non-obese patients with respect to functional outcome scores, reoperation rates, graft subsidence and correction of PI-LL mismatch after long-term follow-up. With similar outcome and reoperation profiles, minimally-invasive approaches to the spine, such as XLIF, may be an acceptable alternative to traditional open procedures in obese patients.

Study Design/UNASSIGNED:Retrospective cohort study. Purpose/UNASSIGNED:To assess long-term clinical outcomes of adjacent segment disease (ASD) in patients who underwent lumbar interbody fusion with percutaneous pedicle screw (PS) instrumentation. Overview of Literature/UNASSIGNED:ASD is a well-known sequela of spinal fusion, and is reported to occur at a rate of 2%-3% per year. There is debate as to whether ASD is a result of the instrumentation and fusion method or is the natural history of the patient's disease. Minimally invasive percutaneous PS augmentation of lumbar interbody fusion aims to prevent the disruption of posterior soft tissue stabilizers. Methods/UNASSIGNED:From 2004-2014, 419 consecutive patients underwent anterior, lateral, or minimally invasive transforaminal lumbar interbody fusion with percutaneous PS placement at a single institution. The mean follow-up was 4.5 years. The primary outcome measure was reoperation due to ASD. Patients were divided into two cohorts: those who underwent revision surgery secondary to ASD and those who did not require further surgery. Radiographic parameters were performed using postoperative radiographs. Patients with a pelvic incidence-lumbar lordosis (PI-LL) mismatch >10° were noted. Results/UNASSIGNED:Revision proportion secondary to ASD was 4.77% (n=20). Mean time to revision surgery was 2.5 years. Revision rate secondary to ASD was 1.1% per year. Patients who developed ASD were younger than those who did not (50.5 vs. 56.9 years, p=0.015). There was no difference in number of levels fused between cohorts. Revision proportion secondary to ASD was similar between approaches (anterior, lateral, minimally invasive). There was no significant difference in PI-LL mismatch between those who underwent revision for ASD and those who did not (22.2% vs 18.8%, p=0.758). Conclusions/UNASSIGNED:ASD rates in patients who underwent percutaneous PS placement were lower than those previously published after open PS placement, possibly related to greater preservation of the posterior stabilizing elements of the lumbar spine.

While extragonadal seminomas resulting in spinal cord compression are rarely reported in the literature, most have been treated with surgical decompression followed by radiation therapy. In this report, we present the unique and interesting case of a 38-year-old man who initially presented as an outpatient with a chief complaint of axial neck pain and lateral thoracic wall pain. After an extensive malignancy workup, he was diagnosed with a primary cervical spine seminoma and was treated with a C6-T1 laminectomy with posterior spinal instrumentation from C5 to T2. He has since undergone chemotherapy with cisplatin, vinblastine, and bleomycin, and at 24-month follow-up, he remains asymptomatic with no signs of recurrent disease.

STUDY DESIGN/METHODS:Systematic review and meta-analysis. OBJECTIVE:To evaluate clinical outcomes, complications, and reoperations of minimallyinvasive posterior cervical foraminotomy (MI-PCF) for unilateral cervical radiculopathy without myelopathy, in comparison to anterior cervical decompression and fusion (ACDF). SUMMARY OF BACKGROUND DATA/BACKGROUND:ACDF is a standard treatment for cervical radiculopathy secondary to lateral disc herniation or foraminal stenosis. Recent studies have suggested MI-PCF to be an effective alternative to ACDF. However, concern for re-operation and whether similar improvements in clinical outcomes can be achieved has led to a debate in the literature. METHODS:We comprehensively searched PubMed, CINAHL Plus, and SCOPUS utilizing terms related to MI-PCF. Two independent reviewers assessed potential studies and extracted data on clinical outcome scores (NDI, VAS-neck and VAS-arm), reoperation proportion and complications. Studies included were on non-central cervical pathology, published in the past 10 years, had a sample size of >10 patients, reported data on minimally-invasive techniques for posterior cervical foraminotomy. Heterogeneity and publication bias analyses were performed. The pooled proportions of each outcome were compared to those of ACDF obtained from two previously published studies. RESULTS:14 studies were included with data of 1216 patients. Mean age of the study population was 51.57 years, 61.8% male and had a mean follow-up of 30 months. MI-PCF resulted in a significantly greater improvement in VAS-arm scores compared to ACDF, and similar improvements in VAS-neck and NDI scores. Proportions of complications and reoperations were similar between the two cohorts. The most common complications were transient neuropraxia, wound-related, and durotomy. CONCLUSION/CONCLUSIONS:Our findings suggest that MI-PCF may be utilized as a safe and effective alternative to ACDF in patients with unilateral cervical radiculopathy without myelopathy, without concern for increased reoperations or complications. LEVEL OF EVIDENCE/METHODS:3.

STUDY DESIGN/UNASSIGNED:Retrospective cohort study. OBJECTIVES/UNASSIGNED:To evaluate the impact of computed tomography angiography (CTA) in the management of trauma patients with cervical spine fractures by identifying high-risk patients for vertebral artery injury (VAI), and evaluating how frequently patients undergo subsequent surgical/procedural intervention as a result of these findings. METHODS/UNASSIGNED:All trauma patients with cervical spine fractures who underwent CTA of the head and neck at our institution between January 2013 and October 2017 were identified. Patients were indicated for CTA according to our institutional protocol based on the modified Denver criteria, and included patients with cervical fractures on scout CT. Those with positive VAI were noted, along with their fracture location, and presence or absence of neurological deficit on physical examination. Statistical analysis was performed and odds ratios were calculated comparing the relationship of cervical spine fracture with presence of VAI. RESULTS/UNASSIGNED:= .007). Of the 25 who had a VAI, 9 were unable to undergo reliable neurologic examination. Of the remaining 16 patients, 5 (31.3%) had motor or sensory deficits localized to the side of the VAI, with no other attributable etiology. CONCLUSIONS/UNASSIGNED:Cervical spine fractures located in the region of the C1-C3 vertebrae were more likely to have an associated VAI on CTA. VAI should also be considered in cervical trauma patients who present with neurological deficits not clearly explained by other pathology. Despite a finding of VAI, patients rarely underwent subsequent surgical or procedural intervention.

As a consultant, the orthopaedic spine surgeon is often asked to evaluate patients with acute-onset extremity weakness. In some cases, patient's deficits can be attributed to nonspinal pathology; therefore, it is important to be aware of nonorthopaedic diagnoses when evaluating these patients. We report a case of thyrotoxic periodic paralysis that was initially confused by the consulting service with spinal pathology. A 32-year-old Hispanic man presented to our emergency department with rapid onset of lower extremity weakness. The consulting team ordered CT of the cervical and lumbar spine, as well as MRI of the lumbar spine which was aborted due to the patient's worsening tachycardia and chest pain. The spine service was subsequently consulted to evaluate the patient. Review of the metabolic panel revealed a low potassium, and additional testing led to the eventual diagnosis of thyrotoxic periodic paralysis. After correction of the patient's potassium, his weakness rapidly resolved, and no additional spinal workup was pursued. We describe this patient's presentation and outline the differential diagnosis for acute, nontraumatic extremity weakness, including both orthopaedic and other medical causes, that the spine surgeon should be aware of when evaluating patients with extremity weakness.

OBJECTIVE:The aim of this study is to present a unique case of a patient who presented to our Emergency Department with evidence of a chronic traumatic spondylolisthesis of the axis with severe displacement treated with anterior cervical discectomy and fusion (ACDF) of C2-C3 as well as and posterior cervical fusion (PCF) of C1-C3. METHODS:One patient with an untreated traumatic spondylolisthesis of the axis with Levine type II injury pattern and 1.2 cm of anterior subluxation underwent ACDF C2-C3 and PCF C1-C3. RESULTS:The patient recovered well, radiographs demonstrated reduction of the anterior subluxation, and the patient reported a neck disability index (NDI) score of 20 at 6-month follow-up with full neurologic function intact. The patient was then lost to follow-up. CONCLUSION/CONCLUSIONS:In this report, we present an alcoholic patient with a history of many falls who presented with a Levine type II traumatic spondylolisthesis of the axis with signs of chronicity seen on magnetic resonance imaging (MRI). We were able to partially reduce the anterior displacement with traction, but needed both anterior and posterior cervical approaches to achieve adequate reduction and stabilization of the injury.

OBJECTIVE:Our purpose was to assess United States data to determine if there were changes in the number of adult cases that graduating orthopaedic surgery resident logged. DESIGN/METHODS:We assessed the Accreditation Council for Graduate Medical Education data from 2010 to 2016 to identify the number of cases that were reported by graduating orthopaedic surgery residents through the United States. Specifically, we analyzed the mean total number of adult cases per graduating resident. We substratified the data based on the subspecialty to include total number of cases performed in: (1) upper extremity; (2) lower extremity; (3) spine; (4) oncology; and (5) trauma. SETTING/METHODS:All data collection was performed at the Seton Hall School of Health and Medical Sciences. PARTICIPANTS/METHODS:All United States orthopaedic surgery residents were considered participants RESULTS: During the study period, the total number of cases performed by each resident had decreased from 1791 to 1311 (p = 0.0001). There was only an increase in the number of pelvis/hip cases (p = 0.0001). Among upper extremity cases, there was a decrease in each subtype of cases (p = 0.0001). There was a decrease in the number of femur/knee, leg/ankle, and foot/toes cases per resident (p = 0.0001). Furthermore, there was a decrease in the number of spine and trauma cases performed (p = 0.0001). There was no difference in the number of oncology cases performed (p = 0.47). CONCLUSIONS:We noted a decrease in the number of cases logged by graduating residents over the past 6 academic years. This provides a great deal of insight into the need for residencies to ensure that the appropriate Accreditation Council for Graduate Medical Education bench marks are met. Future studies should analyze how cases may be increased.