Posttraumatic limb swelling and joint stiffness are not causally related experimental observations in rabbits.

Periarticular and intraarticular fractures frequently cause limb swelling and joint stiffness. The two effects are widely assumed to be related--an assumption long held but never tested. Over a ten-year period, a rabbit hind limb model was developed and tested to ascertain methods of preventing or reducing limb swelling and joint stiffness after a local skeletal injury. Limb swelling was monitored for the three- to four-week duration of the studies by volume displacement, and joint stiffness was determined arthrographically. Mechanical treatment modalities tested included limb pressurization, passive motion of varying duration (from four to 24 hours daily), creation of an intraarticular hematoma, and creation of dependent edema. Chemical modalities tested included systemic and intraarticular steroids, intramuscular and oral nonsteroidal antiinflammatory drugs, topical dimethyl sulfoxide, two antihistamine drugs, and two diuretics. At statistically significant levels, all of the modalities tested affected swelling or stiffness, but only terfenadine, an antihistamine, affected both. Treatment with terfenadine resulted in decreased stiffness but increased swelling. When reviewing the results of all of the treatment modalities in concert, it is apparent that, in this model, limb swelling and joint stiffness after injury are not causally related. The significance of this work in forthcoming clinical trials for treatment of posttraumatic joint stiffness are noteworthy.