Static Magnetic Fields within Spinal Interbody Cages for the Promotion of Spinal Arthrodesis: A Pilot Study.

BACKGROUND: Spinal arthrodesis is a commonly performed spinal operation. Spinal arthrodesis can be complicated by pseudoarthrosis and resultant hardware failure. Static magnetic fields (SMF) have the ability to improve bone fusion. We seek to assess the feasibility of the construction and implantation of a lumbar interbody cage equipped with a SMF in a caprine model. METHODS: Six skeletally mature female Boer goats underwent a lateral approach for placement of an interbody graft at lumbar (L) 1-2 and 3-4. The goats were divided into 2 groups of 3 animals. The interbody graft contained a neodymium iron boron magnet in the experimental group and a nonmagnetic titanium sham in the control group. Both groups contained a synthetic bone graft. Blinded radiographic and histologic evaluation was performed at predetermined timepoints to assess degree of bony fusion and osseointegration. RESULTS: All 6 goats underwent successful placement of lumbar interbody grafts. At the 1-month postoperative computed tomography, 1 goat in the experimental group and 1 goat in the control group were noted to have dislodged their intervertebral cage. Qualitative radiographic and histologic evaluation identified enhanced bone formation, bone density, and osteointegration of the graft in the experimental group. CONCLUSIONS: A spinal interbody cage containing a neodymium iron boron magnet for the production of a local SMF is feasible. Preliminary data suggests enhanced bone formation, bone density, and osseointegration of the graft.

Anticoagulant Medications and Operative Subdural Hematomas: A Retrospective Cohort Study Evaluating Reoperation Rates.

BACKGROUND: Anticoagulant therapy is common and complicates the operative management of acute and mixed-density subdural hematomas (SDHs). The risk of reoperation inferred by anticoagulant (AC) medication and the ability of reversal agents to reduce hemorrhagic complications in patients presenting with AC-associated SDHs are not fully understood. METHODS: Data were collected for 288 consecutive patients treated with craniotomy or craniectomy for evacuation of an acute or mixed-density SDH between 2012 and 2017 at 2 academic institutions. Primary end points were reoperation within 30 days and functional outcome at discharge. Groups were compared based on AC use. Logistic regression models were used to identify predictors of reoperation and functional outcome at discharge. RESULTS: Forty-six patients on ACs and 242 with no AC history were analyzed. All patients on AC underwent AC reversal before hematoma evacuation. Reoperation rates between groups were not significantly different (10.9% vs. 12.4%; P = 1.00); however, time to reoperation was significantly shorter in those on ACs (0.8 ± 1.1 days vs. 6.8 ± 10.4 days; P = 0.04). Aspirin use was independently associated with the need for reoperation (odds ratio, 3.05; confidence interval, 1.30-7.19; P = 0.01). Patients taking ACs were significantly older, had more medical comorbidities and were more likely to have a higher modified Rankin Scale score at discharge. CONCLUSIONS: Anticoagulant use was not associated with an increased reoperation rate, suggesting that reversal of AC may have eliminated the hemorrhagic risk conferred by these medications. Patients on ACs were significantly older, harbored more medical comorbidities, and had a worse functional outcome at discharge.

Effect of patient transfer on outcomes after open repair of ruptured abdominal aortic aneurysms.

Patients with ruptured abdominal aortic aneurysms (RAAAs) benefit from treatment in high-volume facilities. This study explored the effect of patient transfer on outcomes and the relationship between hemodynamic status and mortality. We performed a retrospective review of 83 consecutive patients who had open repair for RAAA at a single tertiary facility. The patients were divided into two groups based on arrival in the local emergency department, "local" (n = 44) versus "transfer" (n = 39) from an outside institution, and into three categories of hemodynamic status: (a) no obtainable blood pressure, "pulseless"; (b) requiring vasopressor support, "pressors"; and (c) no vasopressor support, "no pressors." Thirty-day mortality was 21.4%. There was no difference in mortality between the local (18.2%) and transfer (25.6%) patients (p = .41). There were no deaths during transfer. There was no difference in the hemodynamic status of the transfer versus the local group (p = .34). The mortality by category was pulseless, 100% (3 of 3); pressors, 71.4% (10 of 14); and no pressors, 7.6% (5 of 66) (p < .0001). Actuarial survival was 66%, 64%, and 62% at 1, 3, and 5 years, respectively. Patient transfer does not adversely affect mortality after RAAA repair. Patients without a palpable pulse and those requiring hemodynamic support have a significantly higher mortality.