Misaligned Versus Straight Placement of Anterior Cervical Plates: A Clinical and Radiologic Outcomes Study.

BACKGROUND: In anterior cervical diskectomy and fusion (ACDF), misaligned plates are concerning because of the risk of screw-and-plate failure; however, these plates also hypothetically have the potential for asymmetric micromotion on the facet and uncovertebral joint. The aim of this study was to determine whether misaligned plate placement during ACDF had clinical benefits compared with straight plate placement. METHODS: Postoperative AP radiographs of 128 consecutive patients who underwent ACDF with anterior cervical plate (ACP) fixation were reviewed, and plate alignment was assessed. Patients were separated into control group 1 (straight plates) or group 2 (misaligned plates). RESULTS: The mean age of patients was 51.5 ± 0.9 years, and women represented 51% of the total population. There was no significant difference between groups with regard to the preoperative visual analog scale (VAS) and Neck Disability Index (NDI) scores (P = 0.744 and P = 0.943, respectively). At 6 weeks postoperatively, the VAS scores for group 1 decreased from 7.6 ± 0.2 to 4.0 ± 0.2 compared with the scores in group 2, which decreased from 7.7 ± 0.2 to 2.1 ± 0.1, which demonstrated statistical significance (P = 0.019). At 2-year follow-up, no significant difference was demonstrated between the groups' VAS and NDI scores (P = 0.670 and P = 0.266). CONCLUSION: Misaligned plates have increased torsional strength and are associated with better clinical outcomes compared with those of straight plates in the early postoperative period. After fusion, no significant difference in clinical outcomes between the groups was noted, which may reduce the concerns regarding misaligned plates. LEVEL OF EVIDENCE: Retrospective comparative study.

Eligibility of Outpatient Spine Surgery Candidates in a Single Private Practice.

STUDY DESIGN: Level III. PURPOSE: To retrospectively review the eligibility of surgical patients meeting predetermined outpatient surgery criteria in a single-surgeon private practice. SUMMARY OF BACKGROUND DATA: There is a burgeoning awareness among patients, surgeons, and insurers of the cost benefits and safety of outpatient spine surgeries. At the end of 2014, Centers for Medicare & Medicaid Services have released its final 2015 payment rules and codes for spinal decompression and fusion. This move confirms the safety of procedures being performed in the ambulatory surgery centers (ASCs). METHODS: We conducted a database review between 2008 and 2014 and identified 1625 orthopedic procedures. All nonsurgical spine procedures were excluded from the study. Eligibility for outpatient spine surgery was based on criteria generated from a combination of published standard of care for major operations and the chief surgeon's experience. A matched cohort based on type of surgery in each facility of all spine surgery patients was created, group 1 (hospital patients) and group 2 (ASC patients). RESULTS: A total of 708 patients underwent spinal surgery during this time period with a 53% female population. A total of 557 of 708 (79%) patients were eligible for outpatient spine surgery. There were 210 surgical procedures in group 1 (inpatient) comprised of 72 decompression and 138 fusion procedures. In group 2 (outpatient), there were 347 procedures made up of 150 patients undergoing decompression and 197 undergoing fusion or disc replacement. To confirm that hospital procedures are eligible to be performed in the ASC, the χ test was performed. We found that ASC-eligible hospital patients can indeed be done in an ASC (P=0.037). CONCLUSIONS: Outpatient spine surgery is feasible in 79% of patients in this single-surgeon private practice. On the basis of these results, a majority of spine procedures can be performed in an outpatient setting following our eligibility criteria.

Clinical Outcomes With Midline Cortical Bone Trajectory Pedicle Screws Versus Traditional Pedicle Screws in Moving Lumbar Fusions From Hospitals to Outpatient Surgery Centers.

STUDY DESIGN: Level III. OBJECTIVE: To report on the outcomes of midline cortical bone trajectory (CBT) pedicle screw surgical technique for posterior lumbar fixation in the outpatient surgery center (OSC) compared with traditional pedicle screws in the hospital. SUMMARY OF BACKGROUND DATA: Traditional pedicle screws have been the gold standard for posterior lumbar fusion. Advances in spine surgery, including less invasive procedures have propelled the design of instruments and implants to achieve greater posterior spinal fixation, with decreased tissue destruction and higher safety margins. Biomechanical studies have validated the superior pullout strength of cortical screws versus the traditional pedicle screws and represent an opportunity to perform safe lumbar fusions in OSCs with same day discharge. MATERIALS AND METHODS: The medical records of 60 patients with prospectively collected data were reviewed. Two matched cohort groups consisting of 30 patients each, CBT pedicle screws performed in OSC patients (group 1) was compared with traditional pedicle screws performed in hospital patients (group 2). Outcomes were assessed with self-reported Visual Analog Scale (VAS) scores, Oswestry Disability Index scores, and radiologic fusion rate. RESULTS: Totally, 33 males and 27 females, age range (28-75), average 58±3 years. Average body mass index was 29±1.15 kg/m. A total of 65% of surgeries were at L5-S1 level. Significant improvement noted in VAS back pain scores in the OSC group from 7.8±0.5 to 2.5±0.7, P=0.001. Comparing intergroup VAS back pain scores and Oswestry Disability Index scores, OSC group demonstrated significant improvement, P=0.004 and 0.027, respectively. Fusion rate at 2 years was similar, P=0.855 between groups. CONCLUSIONS: We successfully transitioned our lumbar fusions from hospitals to OSCs using a midline CBT pedicle screw technique. Although traditional pedicle screw placement is effective and may be viable in an OSC, we see more advantages to use midline cortical screws over traditional pedicle screws.

Lateral Lumbar Interbody Fusion in Ambulatory Surgery Centers: Patient Selection and Outcome Measures Compared With an Inhospital Cohort.

STUDY DESIGN: Comparative analysis. OBJECTIVE: To evaluate the safety and outcomes of moving lateral lumbar interbody fusion (LLIF) surgeries to an outpatient setting. SUMMARY OF BACKGROUND DATA: LLIF has been popularized as a less invasive lumbar fusion surgery as an alternative approach to anterior lumbar interbody fusions, posterior lateral interbody fusion, and transforaminal lateral interbody fusion (TLIF). Lumbar fusions have been traditionally performed in a hospital setting because of the potential blood loss, length of surgery, and need for longer recovery. There is a movement to transition spine surgeries to outpatient settings with many benefits afforded by less invasive techniques and technologies. METHODS: The medical records of 70 consecutive patients with prospectively collected data were retrospectively reviewed. Two cohort groups, inpatients (40 patients) and outpatients (30 patients), were created. Patient demographics, risk factors, and body mass index (BMI) were evaluated to determine inclusion criteria for study. RESULT: A total of 34 males and 36 females, age range (31-71) average 59.3 ±â€Š2.3 years. Average BMI was 29.6 ±â€Š1.1 kg/m. The most common level operated on being L3-L4 in both groups (63%). Mean preoperative inpatient Oswestry Disability Index (ODI) increased from 48.5 ±â€Š3.0 to 55.5 ±â€Š3.2 compared with outpatient preoperative ODI means reduced from 45.2 ±â€Š5.1 to 39.1 ±â€Š4.6. There was no statistically significant change in VAS scores between groups. There was however significant improvement in outpatient preoperative VAS scores from 7.3 ±â€Š0.5 to 4.1 ±â€Š0.5, P = 0.045. CONCLUSION: The outcomes of the present study have shown that patients who had LLIF performed in the outpatient setting had statistically significant improvement in ODI scores compared with the inpatient setting (P = 0.013). Fusion was achieved in all patients and there was no evidence of implant failure or subsidence. Complications were transient in both settings. We conclude that outpatient LLIF improves patients' outcomes with similar safety profile as the hospital setting. LEVEL OF EVIDENCE: 3.

Pharmacokinetics of methylprednisolone acetate after intra-articular administration and subsequent suppression of endogenous hydrocortisone secretion in exercising horses.

OBJECTIVE: To determine the pharmacokinetics of methylprednisolone (MP) and the relationship between MP and hydrocortisone (HYD) concentrations in plasma and urine after intra-articular (IA) administration of 100 or 200 mg of MP acetate (MPA) to horses. ANIMALS: Five 3-year-old Thoroughbred mares. PROCEDURES: Horses exercised on a treadmill 3 times/wk during the study. Horses received 100 mg of MPA IA, then 8 weeks later received 200 mg of MPA IA. Plasma and urine samples were obtained at various times for 8 weeks after horses received each dose of MPA; concentrations of MP and HYD were determined. Pharmacokinetic-pharmacodynamic estimates for noncompartmental and compartmental parameters were determined. RESULTS: Maximum concentration of MP in plasma was similar for each MPA dose; concentrations remained greater than the lower limit of quantitation for 18 and 7 days after IA administration of 200 and 100 mg of MPA, respectively. Maximum concentration and area under the observed concentration-time curve for MP in urine were significantly higher (approximately 10-and 17-fold, respectively) after administration of 200 versus 100 mg of MPA. Hydrocortisone concentration was below quantifiable limits for ≥ 48 hours in plasma and urine of all horses after administration of each MPA dose. CONCLUSIONS AND CLINICAL RELEVANCE: Pharmacokinetics of MP may differ among IA MPA dosing protocols, and MP may be detected in plasma and urine for a longer time than previously reported. This information may aid veterinarians treating sport horses. Further research is warranted to determine whether plasma HYD concentration can aid identification of horses that received exogenous glucocorticoids.