Is Univalving or Bivalving of Long Arm Casts for Forearm Fractures Necessary?

Following cast application, little is known regarding the need to split the cast, either in a univalve (a split along a single side of the cast) or bivalve (a split along both sides of the cast) fashion. Theoretically, the splitting of the cast allows for expansion and soft tissue swelling. However, review of the literature yields a paucity of evidence demonstrating the efficacy of splitting a cast. In a study by Nietosvaara et. al, a retrospective examination of 109 pediatric patients initially treated with closed cylindrical casting for closed forearm fractures were evaluated. Of these 109 patients, one-sixth required the initial cast to be split, trimmed, or removed secondary to post-traumatic swelling.

However, the splitting of a cast is not without risks in itself. Once the initial swelling dissipates, a univalved or bivalved cast can become excessively loose. This loosening has been associated with a loss of reduction. If the loss or reduction is substantial, it may require a re-reduction or operation to correct. In addition, with every use of the cast saw a patient is placed at risk for iatrogenic cast saw injury. Thermal burns and abrasions from cast saws can cause lifelong emotional and physical scars for a patient. They can also be an inciting event for litigation against the hospital and or provider, with settlements averaging greater than $12,000 per centimeter of cast saw injury.