The complex musculosketal structure of the hand and wrist enable a wide range of movements and provide the body with the ability to precisely manipulate objects in many different ways.
A total of 27 bones constitute the basic skeleton of the wrist and hand. The forearm's ulna and radius support the many muscles that manipulate the bones of the hand and wrist.
Fractures happen when enough force is applied to a bone to break it. This is typically the result of trauma, but in some instances may be due to a disease process such as osteoporosis or cancer. Falls, sports injuries, and car accidents are the most frequent sources of trauma.
Fractures in the hand and wrist are common injuries. They may occur as an isolated injury, or in conjunction with other soft tissue injuries. Because of the delicate anatomy of the hands and wrists, fractures must be treated urgently. Otherwise, the bones may not heal in the proper alignment causing permanent damage as well as laying the groundwork for future problems. Fractures that extend into a joint may cause arthritis years later.
Commonly fractured bones in the hand and wrist include:
- Distal Radius Fractures - This occurs when the radius bone of the forearm breaks close to the wrist. The most common cause is a fall on an outstretched arm.
- Finger Fractures - The bones of the fingers are known as phalanges. Each finger has three phalanges, except the thumb, which has two. A finger fracture is a crack or break in one or more of these bones. A direct blow to the finger is the most common cause.
- Thumb Fractures - These occur when either of the two phalanges, which make up the thumb break. Bennett and Rolando fractures happen at the base of the thumb and involve the joint between the thumb metacarpal and one of the bones of the wrist. These fractures are more difficult to treat.
- Boxer’s Fracture - A fracture of one of the metacarpal bones of the hand. This fracture typically occurs across the neck of the bone and is often associated with hitting an object with a closed fist.
- Hook of Hamate Fracture - The hamate is one of the largest carpal bones of the wrist and is located on the pinky side of the palm. It has a protrusion called the "hook of hamate." Hook fractures can occur from a direct injury to the bone or from an indirect blow that occurs most commonly in sports.
- Scaphoid Fracture - The scaphoid is one of the small bones in the wrist. It is located on the thumb side of the wrist, in the area where the wrist bends. A scaphoid fracture is usually caused by a fall on an outstretched hand, with the weight landing on the palm.
Hand and wrist fractures typically cause pain and swelling. The pain increases with movement. It can be difficult to bend the fingers and grip an object. Additionally there can be tenderness, bruising, numbness, tingling, and obvious deformity.
Hand and wrist fractures can injure nearby nerves and blood vessels. When checking for a broken bone, the doctor will also assess if blood flow is impaired or if there is any evidence of nerve damage. Many fractures can be diagnosed with a complete physical exam and an x-ray. Additional tests such as an MRI, CT scan, or a bone scan may be ordered to obtain a more detailed look at the injured area. Once diagnosed, treatment depends on the type and severity of the fracture.
A splint or cast may be used to provide stability and protect non-displaced fractures as well as fractures that have been set. If the ends of the bone are not in alignment they will have to be brought back into proper position. This sometimes requires a surgical procedure and may be supplemented with screws, pins, or plates. When a bone is crushed or segments missing, a bone graft may be necessary. Severe fractures may require additional procedures such as joint reconstruction or replacement.
The average healing time process for a broken bone is six to eight weeks. In cases where surgery is required, this may be a longer period of time. Periodic x-rays can be taken to ensure that the fracture is healing properly. The doctor will provide guidelines for a return to activity as well as recommendations for a physical therapy regimen. Strict adherence to a rehabilitation program in order to restore flexibility, range of motion, and function is essential.