Wrist Fractures II

Distal Radius Fractures: Distal radius fractures (fractures of the big bone of the wrist) are the most common fracture in the entire human body. Despite the fact that some physician’s belief that ‘they all do well’, they are probably the most treacherous fracture in the entire arm. If they heal in poor position, wrist fractures often lead to wrist pain, arthritis and stiffness. In addition, as the wrist is the foundation of the hand, if the wrist heals in poor position the fingers may get stiff and hand function may be compromised. Many patients whose distal radius healed in poor position have required multiple surgeries to correct the deformity and to release the fingers to regain motion.

Not all distal radius fractures require surgery. Some may be treated in a simple cast. However, many will do better if surgically fixed to assure that they heal in good position. Often, a CT scan is needed to obtain more information to assist with this decision making. It is important that the ultimate position of healing be acceptable. Many traditional forms of fixation, such as pins and external fixation have a high complication rate and may allow the fracture to collapse back into a poor position after they are removed. Although the fracture may have initially been placed into an acceptable position, if it collapses and ultimately heals an unacceptable position, hand and wrist function may be compromised. Newer plates placed on the bottom of your wrist have screws that lock into them, providing long-lasting rigid fixation that often allows for earlier motion and a quicker return to function. With the wrist held firmly in a good position, hand use is encouraged so that stiffness and dysfunction don’t often occur.

Wrist fractures may be associated with ligament injuries. Some of these ligament injuries may be diagnosed and treated at the time of surgery. Others may not be detected until after the fracture has healed. If pain or other problems continue following fracture healing, a hand surgeon can determine if there are any additional injuries to your wrist, and what can be done about them.

Scaphoid Fractures: The scaphoid is probably the worst bone in the entire arm to break. It has a poor blood supply, it is subjected to high stresses, and it is a very important wrist bone. Scaphoid fractures are serious injuries. Textbooks have been written about them. They love to not heal (ie. ‘go on to non-union’) and/or have part of the bone die (avascular necrosis: like a heart attack of bone). And if they don’t heal, the wrist inevitably develops arthritis.

Scaphoid fractures take a long time to heal. In adults, a fresh fracture can take 3-6 months to heal, depending on where it’s broken. Some locations of scaphoid fractures have a very poor rate of healing, even if casted for a prolonged period of time. Some require surgical screw fixation to have a better chance to heal.

Scaphoid fractures often don’t show up on the initial X-rays. They may take 2 weeks to be able to be seen on X-ray. It’s very important not to miss them. So if you injure your wrist and you’re tender over the scaphoid you can either be casted for two weeks and then have repeat X-rays taken, or get an MRI. Althought it’s more expensive, an MRI can diagnose a scaphoid fracture, or not, within 24 hours.

In order to avoid 3 months in a cast, most active patients with scaphoid fractures elect to have a screw placed into their scaphoid percutaneously. Percutaneously means through a very small (1-2 cm) incision. Percutaneous screw placement does not disrupt the blood supply around the scaphoid, allowing it to heal quicker than when using a traditional open incision. If the scaphoid screw is placed within 4 weeks after the fracture, there is a 95% chance of healing. After 4 weeks the success rate drops. This decreased healing can be slowed down by casting the wrist, which is why if a scaphoid fracture is suspected but not proven, a cast is put on until we’re sure the scaphoid isn’t fractured. If the scaphoid fracture is diagnosed and fixed quickly, most times it heals well with no significant loss of motion; it’s almost like it never happened. Displaced fractures (fractures that have moved) will not heal without surgery, and often require an open incision to fix.

Following surgery, if the fracture was treated early (within 4 weeks) immobilization after surgery is only one week; a removeable splint is then used, which allows showering. Sports and heavy lifting must be avoided until the fracture is healed. Certain locations of scaphoid fractures are less stable, and may be casted for 6 weeks or longer. Every scaphoid fracture is different.

Many times patients don’t realize that they’ve broken their scaphoid until many years after the fact. They remember just ‘spraining’ their wrist. The scaphoid may become non-painful as it’s temporarily stabilized by scar. Years later the scar can break due to a minor injury. These non-healed fractures (non-unions) are far more difficult to get to heal and often require an open incision combined with bone graft from the distal radius (large wrist bone). After surgery, these fractures are casted until they heal. Sometimes patients already have wrist arthritis from the unhealed fracture. These patients are often best salvaged by a partial wrist fusion, which work well, but do not provide a normal wrist.