Risk factors for the development of DJK in AIS patients undergoing posterior spinal instrumentation and fusion.

PURPOSE: Typically, selection of lowest instrumented vertebra (LIV) in Adolescent Idiopathic Scoliosis (AIS) is based on the coronal radiograph; however, increasing evidence suggests that fusions proximal to the stable sagittal vertebrae (SSV) on the lateral radiograph can result in distal junctional kyphosis (DJK). The purpose of this study is to compare rates of DJK in patients with AIS that have a discordance between the Lowest Touched Vertebra (LTV) and the SSV and to identify risk factors for developing DJK. METHODS: Patients with AIS Lenke type 1, 2 and 3 curves treated with a posterior spinal fusion were separated into two groups. Group 1 had SSV that was proximal to the LTV whereas group 2 had SSV that was distal to the LTV. Comparisons were made for patients that were fused to the SSV(a), LTV(b) or between(c). Distal junctional angle (DJA) > 5° and increasing kyphosis at the end of the fusion construct were evaluated as risk factors for DJK. RESULTS: The rate of DJK was 0.0% in group 1a, 1b, and 1c compared to 4.3%, 18.5% and 10.0% in groups 2a, 2b and 2c, respectively(p < 0.001). The rate of DJK was 22.9% when the distal junctional angle(DJA) > 5° versus 1.4% when the DJA < 5°(p < 0.001). CONCLUSION: There was a low risk for progression of DJK when the SSV was proximal to the LTV, however, those with SSV distal to the LTV represent a high-risk group. Importantly, the development of DJK occurred almost exclusively in patients with LIV at the thoracolumbar junction which demonstrates that surgeons need to be cautious when ending fusions at T11, T12, and L1 in patients at high risk for DJK. Furthermore, having a distal junctional angle 5° or greater increased the risk of developing DJK by roughly 16-fold. At a minimum of 5-year follow-up, the development of DJK did not appear to adversely impact SRS outcomes or revision rates.

White Cord Syndrome and Acute Tetraplegia After Posterior Cervical Decompression: A Case Report.

CASE: A 55-year-old man undergoes posterior cervical decompression and instrumentation for progressive cervical myelopathy and develops white cord syndrome (WCS) postoperatively with acute tetraplegia. CONCLUSION: WCS is a rare complication of spinal surgery that is thought to be due to reperfusion injury. We diagnosed WCS in our patient through postoperative examination consisting of acute tetraplegia and magnetic resonance imaging revealing increased signal in the cord. In this case, we used intravenous dexamethasone and mean arterial pressure above 90 mm Hg resulting in markedly improved clinical examination.

Intraoperative Neuromonitoring Use Patterns in Degenerative, Nondeformity Cervical Spine Surgery: A Survey of the Cervical Spine Research Society.

STUDY DESIGN: A cross-sectional survey study. OBJECTIVE: To determine the neuromonitoring (NM) usage patterns among cervical spine surgeons when performing degenerative, nondeformity cervical spine surgery. SUMMARY OF BACKGROUND DATA: Intraoperative NM is frequently used in spine surgery. Although there is literature to support the use of NM in deformity surgery, its utility in degenerative cervical spine surgery remains unclear. MATERIALS AND METHODS: A survey was distributed to members of the Cervical Spine Research Society to assess practice patterns of NM use during degenerative cervical spine surgery. The survey consisted of 17 multiple choice questions. The first 3 questions focus on practice experience. The remaining 14 questions pertain to NM practice patterns in the setting of radiculopathy and myelopathy. RESULTS: Significantly more surgeons routinely (>75% of the time) used NM for myelopathy versus radiculopathy (64% vs. 38%, P<0.001). Private practitioners were overall more likely to use NM than academicians (55% vs. 28%, P=0.007 for radiculopathy; 75% vs. 57%, P=0.09 for myelopathy). No significant difference in NM usage was found comparing neurosurgeons and orthopedic spine surgeons. The most commonly cited primary reasons for NM usage were prevention of positioning/hypotension-related neurological complications, and medicolegal protection. CONCLUSIONS: Routine NM use during degenerative cervical surgery is significantly more common in myelopathy and is thought to be of more value than in radiculopathy. However, the most common reasons for usage were to provide medicolegal cover and to mitigate neurological complications related to positioning/hypotension, rather than to protect against direct surgical events. These findings contrast the prevailing notion that NM is beneficial in reducing complications related to events occurring in the surgical site when performing spinal deformity correction. We believe that these data provide an important baseline for informing best practice guidelines and further study regarding appropriate NM use for degenerative, nondeformity, cervical spine surgery.

Thoracolumbar spinal fractures associated with ground level falls in the elderly: An analysis of 254,486 emergency department visits.

STUDY DESIGN: retrospective. OBJECTIVES: To investigate the epidemiology of elderly (age ≥65 years) patients who presented to the emergency department (ED) in the United States with thoracolumbar (TL) fractures after ground level falls. METHODS: Using the National Emergency Department Sample database, we queried all ED visits in the United States from 2009 through 2012 of elderly patients who presented after ground level falls. We identified patients who sustained TL fractures with and without neurological injury. Resulting data was used to analyze the fracture prevalence, ED and patient characteristics, associated injuries, treatment patterns, inpatient mortality, and hospital charges. RESULTS: Of the 6,654,526 ED visits in the elderly for ground level falls, 254,486 (3.8%) were associated with a diagnosis of TL fracture. 39% patients had multiple injuries, and upper extremity fractures were the most common associated injuries. Overall, 55.6% were admitted to the hospital. Of those, 77.7% were treated non-operatively, 20.4% were treated with cement augmentation alone, 1.5% were treated with spinal fusion surgery, and 0.4% were treated with spinal decompression alone. The overall rate of inpatient mortality was 2.14%. CONCLUSIONS: This investigation evaluated the epidemiology of elderly patients who presented to the ED in the United States with TL fractures after ground level falls. The study demonstrated a rather high incidence of TL fractures in this patient cohort. As a result, it is important for ED physicians and orthopaedic surgeons to be highly suspicious of TL fractures in elderly patients who sustain low energy trauma. With the continued aging of the population and rising health care costs, future effort ought to focus on fall prevention and increased surveillance for TL injuries in the elderly.

Fusions ending above the sagittal stable vertebrae in adolescent idiopathic scoliosis: does it matter?

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To validate whether fusions that end proximal to the sagittal stable vertebrae are at risk for developing distal junctional kyphosis in adolescent idiopathic scoliosis. BACKGROUND: Posterior spinal fusion is routinely used for the treatment of patients with adolescent idiopathic scoliosis. Fusions that end in either the lower thoracic or upper lumbar spine have the advantage of preserving motion segments. However, fusions ending proximal to the sagittal stable vertebrae has been shown to be at higher risk for developing distal junctional kyphosis. METHODS: A multi-center database of prospectively enrolled subjects was queried for patients with adolescent idiopathic scoliosis that had Lenke type 1, 2 and 3 curves treated with posterior pedicle screw instrumentation. PA (posterior-anterior) and lateral full-length scoliosis films were obtained on each patient. PA radiographs were viewed to determine the coronal deformity and lateral radiographs to determine the sagittal deformity. Distal junctional kyphosis was defined as a greater than 10° increase in segmental kyphosis between the LIV and the LIV + 1 vertebra. RESULTS: 346 patients were included with 85% being female and mean age of cohort 14.2 [Formula: see text] 2.08 years. At 5 years postoperatively, there was significant difference occurrence of distal junctional kyphosis dependent on whether the LIV relative to SSV with only 2.2% of fusions below the SSV developing DJK compared to 6.5% for fusions ending at the SSV and 15% for fusions with LIV above the SSV (p < 0.001). There was no statistical difference in revision rates based on the relationship of LIV to SSV. CONCLUSION: There is an increased risk for development of DJK in patients with AIS treated with posterior fusion where the LIV was chosen proximal to the SSV. LEVEL EVIDENCE: Level III.

Fusions ending at the thoracolumbar junction in adolescent idiopathic scoliosis: comparison of lower instrumented vertebrae.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To compare clinical outcomes and radiographic parameters between patients treated with a posterior spinal fusion that had a lower instrumented vertebra at T11, T12, and L1. BACKGROUND: Posterior instrumented fusions are well established for treating patients with adolescent idiopathic scoliosis (AIS). Fusions limited to the thoracic spine can adequately correct a spinal deformity while preserving lumbar segmental mobility. However, fusions that end at the thoracolumbar junction have been proposed to cause adjacent segment complications. Studies comparing outcomes between patients who were treated with fusions that end at the thoracolumbar junction with varying LIVs are limited. METHODS: A multicenter database was queried for patients with AIS that had Lenke Type 1 and 2 curves treated with a fusion that had an LIV at T11, T12, or L1. Coronal curve magnitude, degree of junctional kyphosis, C7-central sacral line, thoracic apical translation, and sagittal stable vertebrae were measured. Clinical and functional outcomes were assessed using the Scoliosis Research Society-22 (SRS-22) questionnaire and lumbar flexibility testing. RESULTS: The lower instrumented level was below the sagittal stable vertebrae in 22.7%, 40%, and 66.2% of patients in the LIV-T11, T12, and L1 groups, respectively (p < 0.001). The 5-year postoperative lumbar curve magnitudes were 20.3°, 16.3°, and 14.0° for T11, T12, and L1-LIV, respectively (p < 0.001). No patients in the T11 group (0%), two patients in the T12 group (2.5%), and one patient in the L1 (0.8%) group developed distal junctional kyphosis (p = 0.5). The 5-year postoperative total SRS-22 scores were 4.21, 4.50, and 4.38 (p = 0.029). Lumbar flexion decreased by 0.78 cm in the T11-LIV group, increased by 0.01 cm in the T12-LIV group, and decreased by 0.15 cm in the L1-LIV group (p = 0.434). CONCLUSION: There was no significant difference in SRS-22 scores, development of distal junctional kyphosis or loss of lumbar mobility between patients treated with a spinal fusion that had an LIV at T11, T12, or L1. LEVEL OF EVIDENCE: Level III.

The impact of prophylactic intraoperative vancomycin powder on microbial profile, antibiotic regimen, length of stay, and reoperation rate in elective spine surgery.

BACKGROUND CONTEXT: There is growing concern that the microbial profile of surgical site infection (SSI) in the setting of prophylactic vancomycin powder may favor more resistant and uncommon organisms. PURPOSE: To demonstrate the impact of prophylactic intraoperative vancomycin powder on microbial profile, antibiotic regimen, length of stay (LOS), and reoperation rate in spine surgical site infection. STUDY DESIGN AND/OR SETTING: Retrospective cohort study. PATIENT SAMPLE: the study included 115 postoperative spine patients who were required to return to the operating room for SSI. OUTCOME MEASURES: The outcome measures were microbial profile, reoperation rate, antibiotic regimen, and LOS for patients with postoperative spine infection who either did (treated) or did not (untreated) receive prophylactic vancomycin powder during their index procedure. METHODS: A retrospective review of patients who underwent posterior thoracic and/or lumbar spine surgery between 2010 and 2017 was conducted. Those undergoing surgical treatment of SSI were identified, and patients were divided into two groups - those who were treated with intraoperative vancomycin (treated) and those who were not (untreated). The organism profile for each group was compared. The average LOS, reoperation rate, and number of patients requiring more than 1 antibiotic were calculated for each patient in both groups. RESULTS: There were 5,909 procedures performed. One hundred and fifteen SSIs were identified, resulting in a 1.9% infection rate. Prophylactic vancomycin powder was used in the index procedure for 42 of those cases. 23.8% of cultures in the vancomycin group were polymicrobial and 16.7% were gram-negative compared with 9.6% (p=0.039) and 4.1% (p=0.021) in the untreated group, respectively. In the vancomycin-treated group, 26.1% of patients underwent repeat irrigation and debridement compared with 38.4% in the untreated group (p=0.184). The percentage of patients in the treatment and untreated group who required more than 1 antibiotic was 26.0% and 26.1%, respectively (p=0.984). Mean LOS in the treatment group was 8.0 versus 7.9 for the untreated group (p=0.945) CONCLUSIONS: In this series, vancomycin powder was associated with a higher prevalence of gram-negative and polymicrobial organisms in patients that ultimately developed postoperative SSI. However, this did not adversely affect the need for multiple reoperations, antibiotic regimen, or LOS for these patients.

Outpatient and Inpatient Single-level Cervical Total Disc Replacement: A Comparison of 30-day Outcomes.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: The aim of this study was to compare 30-day postoperative outcomes between patients undergoing outpatient and inpatient single-level cervical total disc replacement (TDR) surgery. SUMMARY OF BACKGROUND DATA: Cervical TDR is a motion-sparing treatment for cervical radiculopathy and myelopathy. It is an alternative to anterior cervical discectomy and fusion (ACDF) with a similar complication rate. Like ACDF, it may be performed in the inpatient or outpatient setting. Efforts to reduce health care costs are driving spine surgery to be performed in the outpatient setting. As cervical TDR surgery continues to gain popularity, the safety of treating patients on an outpatient basis needs to be validated. METHODS: The National Surgical Quality Improvement Program (NSQIP) database was queried for patients who underwent single-level cervical disc replacement surgery between 2006 and 2015. Complication data including 30-day complications, reoperation rate, readmission rate, and length of stay data were compared between the inpatient and outpatient cohort using univariate analysis. RESULTS: There were 531 (34.2%) patients treated as outpatients and 1022 (65.8%) were treated on an inpatient basis. The two groups had similar baseline characteristics. The overall 30-day complication rate was 1.4% for inpatients and 0.6% for outpatients. Reoperation rate was 0.6% for inpatient and 0.4% for outpatients. Readmission rate was 0.9% and 0.8% for inpatient and outpatient, respectively. There were no statistical differences identified in rates of readmission, reoperation, or complication between the inpatient and outpatient cohorts. CONCLUSION: There was no difference between 30-day complications, readmission, and reoperation rates between inpatients and outpatients who underwent a single-level cervical TDR. Furthermore, the overall 30-day complication rates were low. This study supports that single-level cervical TDR can be performed safely in an outpatient setting. LEVEL OF EVIDENCE: 3.

Total Disk Replacement Adjacent to a Multilevel Fusion in the Cervical Spine: A Biomechanical Motion Analysis.

OBJECTIVE: Cervical total disk replacement (TDR) has emerged as a motion-preserving alternative to anterior cervical diskectomy fusion (ACDF). Biomechanical studies have demonstrated that the TDR preserves motion at the diseased segment and minimizes motion and stress at adjacent segments compared with fusion. There has been growing interest in performing a TDR adjacent to a cervical fusion. The purpose of this study was to investigate the kinematics of a TDR after sequentially fusing adjacent segments. METHODS: Seven fresh-frozen human cadaveric cervical spine specimens from C1-T1 were used (average age, 56.2 ± 7.3 years). The effect on cervical flexion-extension motion, by instrumenting a TDR above or below a 1-, 2-, or 3-level fusion, was measured. The protocol consisted of taking fluoroscopic images of each cervical specimen obtained at maximal angular displacement in flexion and extension during force application. Cobb angles were measured on digital radiographs to determine flexion-extension range of motion (ROM). RESULTS: Segmental ROM of the C6-7 TDR in the unfused spine was 11.3° ± 1.9°. After performing a 3-level fusion at C3-6, the motion of the C6-7 TDR increased to 12.9° ± 1.3° (P = 0.33). ROM of the C2-3 TDR in the unfused spine was 5.0° ± 1.1°. After performing a 3-level fusion of C3-6, the C2-3 TDR segmental motion was 6.1° ± 1.3° (P = 0.09). CONCLUSIONS: Biomechanically performing a cervical TDR adjacent to a long-segment fusion did not subject the implant to significantly greater motion than when the TDR was instrumented alone.

The impact of insurance coverage on access to orthopedic spine care.

BACKGROUND: Poor socioeconomic status is a significant barrier to health care in the United States. Policy changes have attempted to expand insurance coverage in hopes of improving access to care. These policies have prioritized primary care and preventative medicine. Access to specialty care, particularly orthopaedic care, has not received the same attention. This study examines access to orthopaedic spine surgery practices based on type of insurance coverage. METHODS: Five offices with board certified orthopaedic spine surgeons were randomly contacted from each state. A fictitious patient provided a scripted surgical indication for their appointment. They provided their insurance coverage as either Medicare, Medicaid or a private plan. Timing of the provided appointment was recorded. Any appointment was subsequently canceled so as not to interfere with the practice's scheduling. RESULTS: Two hundred and thirty-four orthopaedic spine surgery practices were contacted between January and June of 2016. Eighty-six percent of practices accepted a private plan without primary care provider (PCP) referral. Greater than 99% of practices accepted privately insured patients if a PCP referral were included. Those with Medicare were able to obtain an appointment from 81% of practices. No practices contacted in this study offered an appointment to the caller with Medicaid. CONCLUSIONS: Policy changes have expanded insurance coverage in order to improve access to care for patients of low socioeconomic status. There was a significant barrier to accessing spine care for patients with Medicaid insurance. Access was greatest for those with private insurance followed by those with Medicare. This study demonstrates that there is a significant disparity in ability to access spine specialists despite having insurance coverage.

The 5-Item Modified Frailty Index Is Predictive of 30-Day Postoperative Complications in Patients Undergoing Kyphoplasty Vertebral Augmentation.

BACKGROUND: Vertebral compression fractures are the most common spine injury seen in elderly patients. Vertebral augmentation is considered a safe and effective treatment. The ability to predict outcomes based on comorbidities is lacking. The modified frailty index has been used to predict complications after orthopedic and surgical procedures. We hypothesized that despite a low rate of adverse outcomes, postoperative complications after kyphoplasty would be greater in patients who are frail. METHODS: The National Surgical Quality Improvement Program database was queried for patients who underwent kyphoplasty between 2006 and 2015. Complication data including 30-day complications, life-threatening complications, reoperation and readmission rate, and length of stay data was recorded, and 5-item modified frailty index (5i-mFI) scores were calculated. Univariate and multivariate logistic regression analyses were then conducted to analyze frailty as a predictor of postoperative complications after kyphoplasty. RESULTS: In total, 2465 patients were identified (mean age = 73.98). As 5i-mFI increased from 0 to ≥2, the rate of overall complications increased nearly 3-fold from 3.7% to 10.4% (P < 0.001) and the rate of life-threatening complications increased from 0.8% to 2.4% (P = 0.042). In addition, 30-day readmission increased from 8.9% to 12.9% (P = 0.005), adverse hospital discharge increased from 7.6% to 25.6% (P < 0.001), and length of stay increased from 1.66 days to 3.75 days (P < 0.001). Frailty was associated with increased total complications, Clavien-Dindo IV complications, length of stay, and 30-day readmission rates. CONCLUSIONS: The 5i-mFI is a straightforward assessment tool that correlates with outcomes after kyphoplasty. It can be used to help clinicians predict adverse events and facilitate informed discussions with their patients.

Epidemiology and treatment of central cord syndrome in the United States.

BACKGROUND: The objective of this study is to demonstrate the epidemiology and trends in management of patients with central cord syndrome (CCS) who present to the emergency department. Recent literature has reported that surgical treatment for CCS have increased over the previous decades. METHODS: The National Emergency Department Sample (NEDS) was queried from 2009 through 2012 to generate national estimates of patients who presented to the emergency department in the United States and were diagnosed with CCS. RESULTS: From 2009 through 2012, there were 11,975 emergency room visits for CCS (mean age 60 years). The two most common injury mechanisms were: fall (55%) and motor vehicle accident (15%). Concomitant cervical fractures were found in 10% patients. Ninety-three percent of patients were admitted to the hospital directly or after transfer to another facility, and 7% were discharged home. Fifty-five percent of patients were treated non-operatively, 39% were treated with cervical fusion surgery and 6% were treated with laminoplasty. Of patients who underwent cervical fusion, 62% received anterior decompression and fusion, 32% received posterior decompression and fusion, and 6% received combined anterior-posterior decompression and fusion. The incidence of in-hospital mortality was 2.6%. Mortality was associated with older patient age (OR 1.06, P<0.001) and greater comorbidities (OR 1.72, P<0.001). CONCLUSIONS: Majority of patients who presented to the emergency room for CCS in the United States were treated non-operatively. Advanced age and greater comorbidities were the factors that were most associated with increased risk of in-hospital mortality in patients with CCS.