Today, surgically implanted spinal rods are adding stability and alleviate pain for a growing number of the population suffering from back pain. When properly manufactured and installed, these rods support spinal columns and separate compressed vertebrae. As with any medical implant and surgical procedure, lessons learned along the way have contributed toward making the experience a safe and effective alternative to back pain sufferers.
Kinks & Fatigue
These rods must be rigid enough to provide support yet flexible to bend to conform to the unique size and curvature of each spine. Surgical screws are used to affix the metal to the vertebrae. Typically, spinal rods are installed by attaching the end of the rod at a point and moving along the spinal column bending and attaching the metal along the way.
Surgeons generally employ a tool known as a French Bender to flex the rods. (Note: So called because the French invented it with the help of a local electrician. They are often used by electricians for bending conduit.) Early models of these tools often put a kink in the metal at the bending point during instillation. These kinks became stress points weakening the metal and leading to failure. The weakened rods would eventually break creating sharp metal edges that caused painful and often significant damage as these knife-like edges irritated or lacerated soft tissue surrounding the break point. Needless to say there were many instances of failure and resulting lawsuits against manufacturers, surgeons, and healthcare facilities.
Going to School
So what lessons were learned from past failures and how have they contributed to make the procedure more safe and reliable? Today’s improved version of French Benders creates a larger radius when bending the rods. In this way, stress is extended over a larger surface area and not concentrated in one small location significantly decreasing the likelihood of failure. Surgeons have also learned to become increasingly aware to avoid nicks or dents in the spinal rod while bending.
The Cost of Higher Education
Speaking of “going to school” – a quick anecdote on the high cost of education. Several years ago I sent an employee to a seminar. He, along with approximately thirty others, spent the cold and snowy weekend learning about medical metals. As luck would have it, the power went out at the lodge where the seminar was being held. Fortunately, the lodge was equipped with a large fireplace allowing the seminar to go on as scheduled. Throughout the duration of the seminar attendees pitched in carrying wood from the stack out back inside to stoke the fire. Learning took place around the fireside. (Just like Abraham Lincoln!)
That Monday, I met with the employee to discuss the seminar. He showed me a swollen hand and redness and soreness in his arm. I advised him to go to the emergency room right away. There it was determined that he had suffered several bites from a brown recluse spider that was hidden in the wood pile!
I’m happy to report that the employee recovered fully. However, I have no information on the condition of the spider.
John McCloy has plenty more disturbing details about implants gone wrong:
Look out for more horror stories in the future! Find more information on Engineered Assurance here.