Hematoma Block vs. Bier Block: Which is More Effective for Closed Fracture Reduction?

The investigators objective of this study is to evaluate the effectiveness of hematoma block compared to intravenous regional anesthesia (Bier block) during closed reduction of distal radius fractures. Distal radius fractures represent one of the most commonly treated skeletal injuries in the US. Achieving a fracture reduction that restores anatomy of the distal radius is of paramount importance. Reductions that re-establish anatomical parameters can prevent a patient from requiring operative intervention for the fracture, eliminating the risks as well as costs that are inherent in undergoing surgery.

Intravenous regional anesthesia (IVRA) or 'Bier block' is an effective technique used to provide anesthesia to the distal extremity. IVRA involves venous infiltration of a local anesthetic with concomitant use of a tourniquet to restrict infiltration solely to the intended extremity. Hematoma block involves local infiltration of local anesthetic directly into the site of a hematoma to provide analgesia. Both IVRA and hematoma blocks can be used to provide analgesia during a variety of procedures including fracture manipulation and reduction, but there is a paucity of data regarding the possible superiority of one means of analgesia.

To date, only a few comparative studies has been performed regarding the use of these two analgesia methods. Numerous investigators have conducted studies evaluating these two methods of analgesia; but these studies were of relatively poor quality, are older (prior to 1995) or did not individually look at all radiographic parameters that are important to orthopedic surgical providers when determining if a distal radius fracture needs surgery, particularly ulnar variance and articular step-off or gapping.

The investigators institution is one of the few in the country that utilizes bier blocks, performed by orthopedic residents, for most closed reductions in the emergency department. This quality makes the investigators institution uniquely qualified and motivated to perform the proposed investigation.

Concerns regarding the implementation of the Bier block surround its' safety profile, including possible increased risk of carpal tunnel, and in more severe cases, seizures or cardiac arrest. Despite the frequency with which investigators manage distal radius fractures, our experience has been that the major complication profile of this technique is minimal. Other studies have supported the notion that catastrophic complications are rare and the most common "complication" is tourniquet pain. These studies are limited by their nature in that anesthesia or emergency medicine providers performed the Bier blocks, while in most instances having the orthopaedic provider perform the block as well as the reduction is more efficient.