Cobalt Chrome Spine Implants in Kids Set Off Airport Alarms (MedPageToday)
But stainless steel devices were invisible to TSA metal detectors.
LAS VEGAS — Children with cobalt chrome spinal fusion implants, but not stainless steel, triggered airport security alarms 24% of the time,researchers reported here.
Out of 50 pediatric spinal fusion patients, 24% of those with cobalt chrome versus none of the children with stainless steel implants set off Transportation Security Administration (TSA) metal detector or body scanner alarms, Regina P. Woon, MPH, of Children’s Hospital Los Angeles, reported at the annual meeting of the American Association of Orthopaedic Surgeons.
“In our series, cobalt chrome constructs are more likely to incur additional airport security screening when compared with more traditional stainless steel constructs,” Woon said in her presentation at the meeting.
However, she said, one of the patients in the study who set off the alarm in a U.S. airport reported going through airport security outside the country where she did not trigger the alarm. “We’re not exactly sure what the levels of detection are for the various airports,” Woon said.
Her team surveyed 33 patients with cobalt chrome and 17 with stainless steel implants. The children were ages 4 to 22 (average 14) at the time they underwent spinal fusion surgery. All surgeries were performed from 2004-2013.
Patients who had alerted the TSA or airline about the implant prior to arriving at the airport were excluded from the study.
This study only included patients with pedicle screws for 80% or more of their anchors.
Out of 28 patients with cobalt chrome rods, 18% set off the archway metal detectors, and 17% triggered full-body scanner alarms.
In patients with cobalt chrome implants, the number of anchors used didn’t appear to effect the risk of setting off an alarm:
- Two children with 0-10 anchors set off alarms
- Five children with 11-20 anchors set off alarms
- One child with 21-28 anchors set off an alarm
Also, the number of levels fused didn’t predict alarms in cobalt chrome patients:
- One child with 2-5 levels fused set off an alarm
- Four children with 6-10 levels fused set off alarms
- Three children with 11-15 levels fused set off alarms
In cobalt chrome patients, the authors didn’t find significant differences between the alarm detection rates and the levels fused (P=0.03), the number of anchors (P=0.15), or the rod diameter (P=0.17), although the study may have been underpowered to detect such differences.
Previous research by Ramirez et al. found that roughly half of all orthopedic implants set off metal detectors in an airport setting. And, compared with stainless steel, cobalt chrome and titanium implants were more likely to trigger the alarm. Chinwalla et al. found that titanium did not set off any walk-through airport metal detectors.
The authors listed a couple of limitations including potential recall bias and retrospective study design.