I know, I know, you’re not mice. But hear me out. There are three types of injuries I see very regularly that take a lot longer to heal than others: Rib strains, injuries to nerves, and ligament strains.

And now two recent studies have shown that smokers are at risk of having even slower ligament healing. “Exposure to cigarette smoke delays the chondrogenic phase of fracture repair as well as ligament healing in mice”, according to two reports in the December 2006 issue of the Journal of Orthopaedic Research

In the first study, a team of researchers investigated whether smoking cigarettes would interfere with the ability of mice to generate new matrix at the site of medial collateral ligament injury (it’s on the inside of your knee).

Smoke-exposed mice showed significantly less increase in cell density at the site of injury at day 3 and day 7, the investigators report.

By day 7, controls showed significantly higher type I collagen gene expression than did smoking animals, the report indicates. Translation – non smokers heal quicker.

In the second study, mice were randomly assigned to a control group or to a group in which they were exposed to smoke in a smoking chamber for 6 days per week for a month, before undergoing tibial fracture under anesthesia. You read correctly, they broke the little fellas legs!

By day 14 after fracture, the report indicates, the poor little passive smoking mice were still struggling to move on from growing cartilage to growing bone over the fracture, whereas the cartilage had been replaced by bone in the normal controls.

Take home message – smoking slows your ligament and bone healing rates.

Looking for a new years resolution? Look no further…