Browse

You are looking at 1 - 10 of 45 items for

  • User-accessible content x
  • By Author: Park, Paul x
Clear All
Free access

Jacob R. Joseph, Jennylee S. Swallow, Kylene Willsey, Andrew P. Lapointe, Shokoufeh Khalatbari, Frederick K. Korley, Mark E. Oppenlander, Paul Park, Nicholas J. Szerlip and Steven P. Broglio

OBJECTIVE

This prospective observational cohort study of high-school football athletes was performed to determine if high-acceleration head impacts (HHIs) that do not result in clinically diagnosed concussion still lead to increases in serum levels of biomarkers indicating traumatic brain injury (TBI) in asymptomatic athletes and to determine the longitudinal profile of these biomarkers over the course of the football season.

METHODS

Sixteen varsity high-school football athletes underwent baseline neurocognitive testing and blood sampling for the biomarkers tau, ubiquitin C-terminal hydrolase L1 (UCH-L1), neurofilament light protein (NF-L), glial fibrillary acidic protein (GFAP), and spectrin breakdown products (SBDPs). All athletes wore helmet-based accelerometers to measure and record head impact data during all practices and games. At various time points during the season, 6 of these athletes met the criteria for HHI (linear acceleration > 95g and rotational acceleration > 3760 rad/sec2); in these athletes a second blood sample was drawn at the end of the athletic event during which the HHI occurred. Five athletes who did not meet the criteria for HHI underwent repeat blood sampling following the final game of the season. In a separate analysis, all athletes who did not receive a diagnosis of concussion during the season (n = 12) underwent repeat neurocognitive testing and blood sampling after the end of the season.

RESULTS

Total tau levels increased 492.6% ± 109.8% from baseline to postsession values in athletes who received an HHI, compared with 164% ± 35% in athletes who did not receive an HHI (p = 0.03). Similarly, UCH-L1 levels increased 738.2% ± 163.3% in athletes following an HHI, compared with 237.7% ± 71.9% in athletes in whom there was no HHI (p = 0.03). At the end of the season, researchers found that tau levels had increased 0.6 ± 0.2 pg/ml (p = 0.003) and UCH-L1 levels had increased 144.3 ± 56 pg/ml (p = 0.002). No significant elevations in serum NF-L, GFAP, or SBDPs were seen between baseline and end-of–athletic event or end-of-season sampling (for all, p > 0.05).

CONCLUSIONS

In this pilot study on asymptomatic football athletes, an HHI was associated with increased markers of neuronal (UCH-L1) and axonal (tau) injury when compared with values in control athletes. These same markers were also increased in nonconcussed athletes following the football season.

Free access

Anthony L. Asher, Panagiotis Kerezoudis, Praveen V. Mummaneni, Erica F. Bisson, Steven D. Glassman, Kevin T. Foley, Jonathan R. Slotkin, Eric A. Potts, Mark E. Shaffrey, Christopher I. Shaffrey, Domagoj Coric, John J. Knightly, Paul Park, Kai-Ming Fu, Clinton J. Devin, Kristin R. Archer, Silky Chotai, Andrew K. Chan, Michael S. Virk and Mohamad Bydon

OBJECTIVE

Patient-reported outcomes (PROs) play a pivotal role in defining the value of surgical interventions for spinal disease. The concept of minimum clinically important difference (MCID) is considered the new standard for determining the effectiveness of a given treatment and describing patient satisfaction in response to that treatment. The purpose of this study was to determine the MCID associated with surgical treatment for degenerative lumbar spondylolisthesis.

METHODS

The authors queried the Quality Outcomes Database registry from July 2014 through December 2015 for patients who underwent posterior lumbar surgery for grade I degenerative spondylolisthesis. Recorded PROs included scores on the Oswestry Disability Index (ODI), EQ-5D, and numeric rating scale (NRS) for leg pain (NRS-LP) and back pain (NRS-BP). Anchor-based (using the North American Spine Society satisfaction scale) and distribution-based (half a standard deviation, small Cohen’s effect size, standard error of measurement, and minimum detectable change [MDC]) methods were used to calculate the MCID for each PRO.

RESULTS

A total of 441 patients (80 who underwent laminectomies alone and 361 who underwent fusion procedures) from 11 participating sites were included in the analysis. The changes in functional outcome scores between baseline and the 1-year postoperative evaluation were as follows: 23.5 ± 17.4 points for ODI, 0.24 ± 0.23 for EQ-5D, 4.1 ± 3.5 for NRS-LP, and 3.7 ± 3.2 for NRS-BP. The different calculation methods generated a range of MCID values for each PRO: 3.3–26.5 points for ODI, 0.04–0.3 points for EQ-5D, 0.6–4.5 points for NRS-LP, and 0.5–4.2 points for NRS-BP. The MDC approach appeared to be the most appropriate for calculating MCID because it provided a threshold greater than the measurement error and was closest to the average change difference between the satisfied and not-satisfied patients. On subgroup analysis, the MCID thresholds for laminectomy-alone patients were comparable to those for the patients who underwent arthrodesis as well as for the entire cohort.

CONCLUSIONS

The MCID for PROs was highly variable depending on the calculation technique. The MDC seems to be a statistically and clinically sound method for defining the appropriate MCID value for patients with grade I degenerative lumbar spondylolisthesis. Based on this method, the MCID values are 14.3 points for ODI, 0.2 points for EQ-5D, 1.7 points for NRS-LP, and 1.6 points for NRS-BP.

Free access

Kanwaljeet Garg, Ankita Aggarwal and Rishab Gupta

Free access

Andrew K. Chan, Erica F. Bisson, Mohamad Bydon, Steven D. Glassman, Kevin T. Foley, Eric A. Potts, Christopher I. Shaffrey, Mark E. Shaffrey, Domagoj Coric, John J. Knightly, Paul Park, Kai-Ming Fu, Jonathan R. Slotkin, Anthony L. Asher, Michael S. Virk, Panagiotis Kerezoudis, Silky Chotai, Anthony M. DiGiorgio, Alvin Y. Chan, Regis W. Haid and Praveen V. Mummaneni

OBJECTIVE

The American Association of Neurological Surgeons launched the Quality Outcomes Database (QOD), a prospective longitudinal registry that includes demographic, clinical, and patient-reported outcome (PRO) data, to measure the safety and quality of neurosurgical procedures, including spinal surgery. Differing results from recent randomized controlled trials have established a need to clarify the groups that would most benefit from surgery for degenerative lumbar spondylolisthesis. In the present study, the authors compared patients who were the most and the least satisfied following surgery for degenerative lumbar spondylolisthesis.

METHODS

This was a retrospective analysis of a prospective, national longitudinal registry including patients who had undergone surgery for grade 1 degenerative lumbar spondylolisthesis. The most and least satisfied patients were identified based on an answer of “1” and “4,” respectively, on the North American Spine Society (NASS) Satisfaction Questionnaire 12 months postoperatively. Baseline demographics, clinical variables, surgical parameters, and outcomes were collected. Patient-reported outcome measures, including the Numeric Rating Scale (NRS) for back pain, NRS for leg pain, Oswestry Disability Index (ODI), and EQ-5D (the EuroQol health survey), were administered at baseline and 3 and 12 months after treatment.

RESULTS

Four hundred seventy-seven patients underwent surgery for grade 1 degenerative lumbar spondylolisthesis in the period from July 2014 through December 2015. Two hundred fifty-five patients (53.5%) were the most satisfied and 26 (5.5%) were the least satisfied. Compared with the most satisfied patients, the least satisfied ones more often had coronary artery disease (CAD; 26.9% vs 12.2%, p = 0.04) and had higher body mass indices (32.9 ± 6.5 vs 30.0 ± 6.0 kg/m2, p = 0.02). In the multivariate analysis, female sex (OR 2.9, p = 0.02) was associated with the most satisfaction. Notably, the American Society of Anesthesiologists (ASA) class, smoking, psychiatric comorbidity, and employment status were not significantly associated with satisfaction. Although there were no significant differences at baseline, the most satisfied patients had significantly lower NRS back and leg pain and ODI scores and a greater EQ-5D score at 3 and 12 months postoperatively (p < 0.001 for all).

CONCLUSIONS

This study revealed that some patient factors differ between those who report the most and those who report the least satisfaction after surgery for degenerative lumbar spondylolisthesis. Patients reporting the least satisfaction tended to have CAD or were obese. Female sex was associated with the most satisfaction when adjusting for potential covariates. These findings highlight several key factors that could aid in setting expectations for outcomes following surgery for degenerative lumbar spondylolisthesis.

Free access

Khoi D. Than, Praveen V. Mummaneni, Kelly J. Bridges, Stacie Tran, Paul Park, Dean Chou, Frank La Marca, Juan S. Uribe, Todd D. Vogel, Pierce D. Nunley, Robert K. Eastlack, Neel Anand, David O. Okonkwo, Adam S. Kanter and Gregory M. Mundis Jr.

OBJECTIVE

High-quality studies that compare outcomes of open and minimally invasively placed pedicle screws for adult spinal deformity are needed. Therefore, the authors compared differences in complications from a circumferential minimally invasive spine (MIS) surgery and those from a hybrid surgery.

METHODS

A retrospective review of a multicenter database of patients with spinal deformity who were treated with an MIS surgery was performed. Database inclusion criteria included an age of ≥ 18 years and at least 1 of the following: a coronal Cobb angle of > 20°, a sagittal vertical axis of > 5 cm, a pelvic incidence–lumbar lordosis angle of > 10°, and/or a pelvic tilt of > 20°. Patients were propensity matched according to the levels instrumented.

RESULTS

In this database, a complete data set was available for 165 patients, and after those who underwent 3-column osteotomy were excluded, 137 patients were available for analysis; 76 patients remained after propensity matching (MIS surgery group 38 patients, hybrid surgery group 38 patients). The authors found no difference in demographics, number of levels instrumented, or preoperative and postoperative radiographic results. At least 1 complication was suffered by 55.3% of patients in the hybrid surgery group and 44.7% of those in the MIS surgery group (p = 0.359). Patients in the MIS surgery group had significantly fewer neurological, operative, and minor complications than those in the hybrid surgery group. The reoperation rates in both groups were similar. The most common complication category for the MIS surgery group was radiographic and for the hybrid surgery group was neurological. Patients in both groups experienced postoperative improvement in their Oswestry Disability Index and visual analog scale (VAS) back and leg pain scores (all p < 0.05); however, MIS surgery provided a greater reduction in leg pain according to VAS scores.

CONCLUSIONS

Overall complication rates in the MIS and hybrid surgery groups were similar. MIS surgery resulted in significantly fewer neurological, operative, and minor complications. Reoperation rates in the 2 groups were similar, and despite complications, the patients reported significant improvement in their pain and function.

Free access

Pierce D. Nunley, Gregory M. Mundis Jr., Richard G. Fessler, Paul Park, Joseph M. Zavatsky, Juan S. Uribe, Robert K. Eastlack, Dean Chou, Michael Y. Wang, Neel Anand, Kelly A. Frank, Marcus B. Stone, Adam S. Kanter, Christopher I. Shaffrey, Praveen V. Mummaneni and the International Spine Study Group

OBJECTIVE

The aim of this study was to educate medical professionals about potential financial impacts of improper diagnosis-related group (DRG) coding in adult spinal deformity (ASD) surgery.

METHODS

Medicare’s Inpatient Prospective Payment System PC Pricer database was used to collect 2015 reimbursement data for ASD procedures from 12 hospitals. Case type, hospital type/location, number of operative levels, proper coding, length of stay, and complications/comorbidities (CCs) were analyzed for effects on reimbursement. DRGs were used to categorize cases into 3 types: 1) anterior or posterior only fusion, 2) anterior fusion with posterior percutaneous fixation with no dorsal fusion, and 3) combined anterior and posterior fixation and fusion.

RESULTS

Pooling institutions, cases were reimbursed the same for single-level and multilevel ASD surgery. Longer stay, from 3 to 8 days, resulted in an additional $1400 per stay. Posterior fusion was an additional $6588, while CCs increased reimbursement by approximately $13,000. Academic institutions received higher reimbursement than private institutions, i.e., approximately $14,000 (Case Types 1 and 2) and approximately $16,000 (Case Type 3). Urban institutions received higher reimbursement than suburban institutions, i.e., approximately $3000 (Case Types 1 and 2) and approximately $3500 (Case Type 3). Longer stay, from 3 to 8 days, increased reimbursement between $208 and $494 for private institutions and between $1397 and $1879 for academic institutions per stay.

CONCLUSIONS

Reimbursement is based on many factors not controlled by surgeons or hospitals, but proper DRG coding can significantly impact the financial health of hospitals and availability of quality patient care.

Free access

Yamaan S. Saadeh, Brandon W. Smith, Jacob R. Joseph, Sohaib Y. Jaffer, Martin J. Buckingham, Mark E. Oppenlander, Nicholas J. Szerlip and Paul Park

OBJECTIVE

Spinal cord injury (SCI) results in significant morbidity and mortality. Improving neurological recovery by reducing secondary injury is a major principle in the management of SCI. To minimize secondary injury, blood pressure (BP) augmentation has been advocated. The objective of this study was to review the evidence behind BP management after SCI.

METHODS

This systematic review was conducted following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Using the PubMed database, the authors identified studies that investigated BP management after acute SCI. Information on BP goals, duration of BP management, vasopressor selection, and neurological outcomes were analyzed.

RESULTS

Eleven studies that met inclusion criteria were identified. Nine studies were retrospective, and 2 were single-cohort prospective investigations. Of the 9 retrospective studies, 7 reported a goal mean arterial pressure (MAP) of higher than 85 mm Hg. For the 2 prospective studies, the MAP goals were higher than 85 mm Hg and higher than 90 mm Hg. The duration of BP management varied from more than 24 hours to 7 days in 6 of the retrospective studies that reported the duration of treatment. In both prospective studies, the duration of treatment was 7 days. In the 2 prospective studies, neurological outcomes were stable to improved with BP management. The retrospective studies, however, were contradictory with regard to the correlation of BP management and outcomes. Dopamine, norepinephrine, and phenylephrine were the agents that were frequently used to augment BP. However, more complications have been associated with dopamine use than with the other vasopressors.

CONCLUSIONS

There are no high-quality data regarding optimal BP goals and duration in the management of acute SCI. Based on the highest level of evidence available from the 2 prospective studies, MAP goals of 85–90 mm Hg for a duration of 5–7 days should be considered. Norepinephrine for cervical and upper thoracic injuries and phenylephrine or norepinephrine for mid- to lower thoracic injuries should be considered.

Free access

Brandon W. Smith, Jacob R. Joseph, Michael Kirsch, Mary Oakley Strasser, Jacob Smith and Paul Park

OBJECTIVE

Percutaneous pedicle screw insertion (PPSI) is a mainstay of minimally invasive spinal surgery. Traditionally, PPSI is a fluoroscopy-guided, multistep process involving traversing the pedicle with a Jamshidi needle, placement of a Kirschner wire (K-wire), placement of a soft-tissue dilator, pedicle tract tapping, and screw insertion over the K-wire. This study evaluates the accuracy and safety of PPSI with a simplified 2-step process using a navigated awl-tap followed by navigated screw insertion without use of a K-wire or fluoroscopy.

METHODS

Patients undergoing PPSI utilizing the K-wire–less technique were identified. Data were extracted from the electronic medical record. Complications associated with screw placement were recorded. Postoperative radiographs as well as CT were evaluated for accuracy of pedicle screw placement.

RESULTS

Thirty-six patients (18 male and 18 female) were included. The patients’ mean age was 60.4 years (range 23.8–78.4 years), and their mean body mass index was 28.5 kg/m2 (range 20.8–40.1 kg/m2). A total of 238 pedicle screws were placed. A mean of 6.6 pedicle screws (range 4–14) were placed over a mean of 2.61 levels (range 1–7). No pedicle breaches were identified on review of postoperative radiographs. In a subgroup analysis of the 25 cases (69%) in which CT scans were performed, 173 screws were assessed; 170 (98.3%) were found to be completely within the pedicle, and 3 (1.7%) demonstrated medial breaches of less than 2 mm (Grade B). There were no complications related to PPSI in this cohort.

CONCLUSIONS

This streamlined 2-step K-wire–less, navigated PPSI appears safe and accurate and avoids the need for radiation exposure to surgeon and staff.

Free access

Praveen V. Mummaneni, Erica F. Bisson, Panagiotis Kerezoudis, Steven Glassman, Kevin Foley, Jonathan R. Slotkin, Eric Potts, Mark Shaffrey, Christopher I. Shaffrey, Domagoj Coric, John Knightly, Paul Park, Kai-Ming Fu, Clinton J. Devin, Silky Chotai, Andrew K. Chan, Michael Virk, Anthony L. Asher and Mohamad Bydon

OBJECTIVE

Lumbar spondylolisthesis is a degenerative condition that can be surgically treated with either open or minimally invasive decompression and instrumented fusion. Minimally invasive surgery (MIS) approaches may shorten recovery, reduce blood loss, and minimize soft-tissue damage with resultant reduced postoperative pain and disability.

METHODS

The authors queried the national, multicenter Quality Outcomes Database (QOD) registry for patients undergoing posterior lumbar fusion between July 2014 and December 2015 for Grade I degenerative spondylolisthesis. The authors recorded baseline and 12-month patient-reported outcomes (PROs), including Oswestry Disability Index (ODI), EQ-5D, numeric rating scale (NRS)–back pain (NRS-BP), NRS–leg pain (NRS-LP), and satisfaction (North American Spine Society satisfaction questionnaire). Multivariable regression models were fitted for hospital length of stay (LOS), 12-month PROs, and 90-day return to work, after adjusting for an array of preoperative and surgical variables.

RESULTS

A total of 345 patients (open surgery, n = 254; MIS, n = 91) from 11 participating sites were identified in the QOD. The follow-up rate at 12 months was 84% (83.5% [open surgery]; 85% [MIS]). Overall, baseline patient demographics, comorbidities, and clinical characteristics were similarly distributed between the cohorts. Two hundred fifty seven patients underwent 1-level fusion (open surgery, n = 181; MIS, n = 76), and 88 patients underwent 2-level fusion (open surgery, n = 73; MIS, n = 15). Patients in both groups reported significant improvement in all primary outcomes (all p < 0.001). MIS was associated with a significantly lower mean intraoperative estimated blood loss and slightly longer operative times in both 1- and 2-level fusion subgroups. Although the LOS was shorter for MIS 1-level cases, this was not significantly different. No difference was detected with regard to the 12-month PROs between the 1-level MIS versus the 1-level open surgical groups. However, change in functional outcome scores for patients undergoing 2-level fusion was notably larger in the MIS cohort for ODI (−27 vs −16, p = 0.1), EQ-5D (0.27 vs 0.15, p = 0.08), and NRS-BP (−3.5 vs −2.7, p = 0.41); statistical significance was shown only for changes in NRS-LP scores (−4.9 vs −2.8, p = 0.02). On risk-adjusted analysis for 1-level fusion, open versus minimally invasive approach was not significant for 12-month PROs, LOS, and 90-day return to work.

CONCLUSIONS

Significant improvement was found in terms of all functional outcomes in patients undergoing open or MIS fusion for lumbar spondylolisthesis. No difference was detected between the 2 techniques for 1-level fusion in terms of patient-reported outcomes, LOS, and 90-day return to work. However, patients undergoing 2-level MIS fusion reported significantly better improvement in NRS-LP at 12 months than patients undergoing 2-level open surgery. Longer follow-up is needed to provide further insight into the comparative effectiveness of the 2 procedures.

Free access

Jacob R. Joseph, Brandon W. Smith, Xilin Liu and Paul Park

OBJECTIVE

Surgical robotics has demonstrated utility across the spectrum of surgery. Robotics in spine surgery, however, remains in its infancy. Here, the authors systematically review the evidence behind robotic applications in spinal instrumentation.

METHODS

This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Relevant studies (through October 2016) that reported the use of robotics in spinal instrumentation were identified from a search of the PubMed database. Data regarding the accuracy of screw placement, surgeon learning curve, radiation exposure, and reasons for robotic failure were extracted.

RESULTS

Twenty-five studies describing 2 unique robots met inclusion criteria. Of these, 22 studies evaluated accuracy of spinal instrumentation. Although grading of pedicle screw accuracy was variable, the most commonly used method was the Gertzbein and Robbins system of classification. In the studies using the Gertzbein and Robbins system, accuracy (Grades A and B) ranged from 85% to 100%. Ten studies evaluated radiation exposure during the procedure. In studies that detailed fluoroscopy usage, overall fluoroscopy times ranged from 1.3 to 34 seconds per screw. Nine studies examined the learning curve for the surgeon, and 12 studies described causes of robotic failure, which included registration failure, soft-tissue hindrance, and lateral skiving of the drill guide.

CONCLUSIONS

Robotics in spine surgery is an emerging technology that holds promise for future applications. Surgical accuracy in instrumentation implanted using robotics appears to be high. However, the impact of robotics on radiation exposure is not clear and seems to be dependent on technique and robot type.