Tag Archives: fracture

What Is: A Pars Fracture / Defect

Radiologists sure know their anatomy! The vast majority of the time, I actually know what they are describing. But every once in a while they’ll toss in some term that I know I probably learned about in medical school (last century). For whatever reason though, I’m just not able to retrieve it.

Which brings me to the pars fracture. Hmm. I figure that if I have to hit the books again to look something up, there are probably a few other trauma professionals out there who are dying to know what it is, too. Here’s a diagram of a typical vertebra:

The arch extending away from the vertebral body consists of the pedicles, which are connected by the lamina. A number of things jut off from this arch, including the transverse and spinous processes and the articular processes.

The area between the lamina and pedicle and adjacent to the articular process is called the pars interarticularis. This area is a bit thinner and flatter than the rest of the arch and can fracture if sufficient acute stress is applied. It can also fracture if enough chronic stress in the area occurs. This pattern is typically seen in the lumbar spine, but may also occur at the cervical level. Thus, a pars fracture or pars defect is simply a fracture through this area.

Another term you may see with regard to the pars is spondylolysis. This is defined as a defect in the pars interarticularis, typically from a fracture. So if you see either of these terms in a radiology report, recognize that they are basically one and the same.

Here is a nice image showing the location of the pars, and the axial CT appearance of “bilateral pars defects.”

Mystery solved! Amaze your friends!

Giving Vitamin D After Fracture

The role of Vitamin D in fracture healing is well known. So, of course, trauma professionals have tried to promote Vitamin D

supplementation to counteract the effects of osteoporosis. A meta-analysis of of 12 papers on the topic relating to hip and other non-vertebral fractures showed that there was roughly a 25% risk reduction for any non-vertebral fractures in patients taking 700-800 U of Vitamin D supplements daily.

Sounds good. So what about taking Vitamin D after a fracture occurs? Seems like it should promote healing, right? A very recent meta-analysis that is awaiting publication looked at this very question.

Unfortunately, there was a tremendous variability in the interventions, outcomes, and measures of variance. All the authors could do was summarize individual papers, and a true meta-analysis could not be performed.

Here are the factoids:

  •  81 papers made the cut for final review
  • A whopping 70% of the population with fractures had low Vitamin D levels
  • Vitamin D supplementation in hospital and after discharge did increase serum levels
  • Only one study, a meeting abstract which has still not seen the light of day in a journal, suggested a trend toward less malunions following a single loading dose of Vitamin D

Bottom line: Vitamin D is a great idea for people who are known to have, or are at risk for, osteoporosis and fractures. It definitely toughens up the bones and lowers the risk of fracture. However, the utility of giving it after a fall has not been shown. Of the 81 papers reviewed, none showed a significant impact on fracture healing. The only good thing is that Vitamin D supplements are cheap. Giving them may make us think that we are helping our patient heal, but it’s not. 

References:  

  • What is the role of vitamin D supplementation in acute fracture patients? A systematic review and meta-analysis of the prevalence of hypovitaminosis D and supplementation efficacy. J Orthopaedic Trauma epub Sep 22 2015.
  • Fracture prevention with vitamin D supplementation: a meta-analysis of randomized controlled trials. JAMA 293(18):2257-2264, 2005.

What Is: The Monteggia Fracture

Yesterday, I wrote about one of the many fractures that occurs during falls onto outstretched hands, the Galeazzi fracture. Today, I’ll describe another one, the Monteggia fracture. Yes, this one is named after another Italian surgeon! And like the other one, the person it was named after was actually the second to describe it.

Think of the Monteggia fracture as the exact opposite of a Galeazzi fracture. The fractured bone is switched, as is the dislocation. Whereas the Galeazzi is a distal radius fracture with a distal ulnar dislocation which pulls the radio-ulnar joint apart, the Monteggia is a proximal ulnar fracture with a proximal radial head dislocation.

Here’s what it looks like:

Of course, the orthopedic surgeons have a classification system for this based on the directions the bones fracture and dislocate. I won’t bore you with the details.

Unlike the Galeazzi fracture, all of these require operative repair, even in children. This helps stabilize the radial head and decreases the incidence of malunion.

What Is: The Galeazzi Fracture?

Orthopedic surgeons have so many names for fractures, it gets confusing! Today, let’s dig in to the “Galeazzi fracture.” This one was named for an Italian surgeon during the early 20th century) although it was actually first described by an Englishman named Cooper a hundred years earlier).

The Galeazzi fracture is an uncommon one, and consists of two components: a radius fracture at the junction of the distal and middle thirds, and a dislocation of the distal radio-ulnar joint. Here’s what it looks like:

Notice the obvious dislocation seen in the lateral view. Of course, a whole classification system has been developed to describe the various nuances of this fracture pattern, but that’s beyond the scope of this post.

What to do about it? This one needs prompt orthopedic consultation, and due to the dislocation component it requires operative management in adults. In children, initial closed reduction is the treatment of choice.

Monday, I’ll describe this fracture’s evil twin, The Monteggia fracture.

Trauma Mythbusters: NSAIDs And Fracture Healing

Trauma hurts like hell. Over the years, we’ve developed quite a few ways of combating this pain. A number of drug classes have been developed to reduce it. One of the more common non-narcotic drug classes are the NSAIDs. As I’ve mentioned before, every drug has dozens of effects. Drug companies market a particular medication based on one of the predominant effects. All the others are considered side effects.

NSAIDs are not unique; they have lots of side effects as well. In 2003, several papers brought to light possible interactions between these drugs and fracture healing. Specifically, there were questions about these drugs interfering with the healing process and of increasing the number of delayed unions or nonunions. But once again, how convincing were these papers, really?

It would seem to make sense that NSAIDs could interfere with bone healing. This  process relies heavily on the regulation of osteoblast and osteoclast function, which itself is regulated by prostaglandins. Since prostaglandins are synthesized by the COX enzymes, COX inhibitors like the NSAIDs should have the potential to impair this process. Indeed, animal studies in rats and rabbits seem to bear this out.

But as we have seen before, good animal studies don’t always translate well to human experience. Although a study from 2005 suggested that NSAID administration in older patients within 90 days of injury had a higher incidence of fracture nonunion, the study design was not a very good one. It is equally likely that patients who required these drugs in this age group may have been at higher risk for nonunion in the first place.

In fact, there are no large, prospective randomized studies that have explored the effect of short-term or long-term NSAID administration on fracture repair. But there have been several smaller studies that showed absolutely no effect on nonunion with short-term administration of this drug class. Yet the dogma that leads us to avoid giving these drugs persists.

A recent analysis looked at the quality of the published research, both for and against NSAID usage in fracture patients. They used the Coleman Methodology Score, which evaluates study size and type, mean followup, detailed description of treatment, subject selection, outcomes, and outcome assessment. The maximum score was 100. 

Here are the factoids:

  • There were 4x as many total subjects in the “NSAIDS are okay” papers than in the “avoid NSAIDS” papers
  • The quality of the “NSAIDS are okay” papers were significantly higher than “avoid NSAIDS” group (59 vs 40)
  • Interestingly, the “avoid NSAIDS” papers are cited twice as often
  • All of the reviews ended with my pet peeve catch phrase “further (good) research is needed”

Bottom line: Once again, the animal data is clear but the human data is not. Although there are theoretical concerns about their use, there is not enough solid risk:benefit information to abandon short-term NSAID use in patients who really need them. NSAIDs can and should be prescribed in patients with short-term needs and simple fractures.

References:

  1. Effects of nonsteroidal anti-inflammatory drugs on bone formation and soft-tissue healing. J AM Acad Orthop Surg 12:139-43, 2004.
  2. Effect of COX-2 on fracture-healing in the rat femur. J Bone Joint Surg Am 86:116-123, 2004.
  3. Effects of perioperative anti-inflammatory and immunomodulating therapy on surgical wound healing. Pharmacotherapy 25:1566-1591, 2005.
  4. Pharmacological agents and impairment of fracture healing: what is the evidence? Injury 39:384-394, 2008.
  5. High dose nonsteroidal anti-inflammatory drugs compromise spinal fusion. Can J Anaesth 52:506-512, 2005.
  6. Nonsteroidal Anti-Inflammatory Drugs and Bone-Healing: A Systematic Review of Research Quality. JBJS Rev 4(3), 2016.