The impact of falling on an outstretched hand can be several times an individual’s body weight, leading to broken bones. In fact, 20% of all upper extremity injuries caused by bicycle falls are fractures.
One of the most common fractures is of the distal radius, the large bone of the forearm that articulates with the smaller carpal bones in the wrist. The break will often lead to pain in the forearm, approximately one inch away from the wrist. More severe breaks could show some deformity if the bones are displaced, which will likely cause the rider to seek immediate medical attention; however, it is important to know that the blood vessels and nerves that supply the hand are funneled into a fairly compressed area in the wrist, and a fracture or the subsequent swelling that occurs could disrupt this neurovascular integrity.
Example of External Fixator
These symptoms include numbness or tingling, discoloration, and temperature change in the hand. Most bike injuries happen over the weekend, when your doctor’s office is closed. If this is the case and you have any of the above symptoms, then you should go to the emergency room. Even without these symptoms, it is important to get evaluated by a hand surgeon soon after the injury occurs in order to initiate treatment.
Wrist fractures, if non-displaced, may be treated with immobilization in a cast; however, any misalignment may cause a loss of function in the wrist and is difficult to correct without surgical fixation. Screws and plates may be placed internally, or a device called an external fixator may be placed to hold the fracture in place.
The scaphoid is a small bone located in the wrist, at the base of the thumb. When a bike rider falls on an outstretched hand, the scaphoid is compressed and could fracture. The primary symptoms are acute pain and tenderness on the thumb side of the wrist lasting longer than a few days, swelling, and limited thumb function. Diagnosis is usually confirmed with X-ray; however, this type of fracture often will not be visible on X-ray until a week after the injury. In this case, the doctor will splint the patient’s hand and have them return in one week for a repeat exam. If the fracture is located further toward the thumb, then the treatment may be immobilization in a short arm cast for several weeks. If the bone is fractured more toward the forearm, surgical treatment may be necessary as the scaphoid has poor blood supply in this area.
Surgical treatment consists of placing a small screw or wire through the bone fragments to create proper alignment. In some cases where the scaphoid has broken into several pieces, a bone graft taken from another part of the patient’s body may be used to stimulate healing. In all cases, there will be a period of immobilization and limited activity, followed by physical or occupational therapy by one of our therapists that specialize in hand rehabilitation.
Wrist and Finger Sprains
A sprain occurs when a ligament holding one bone to another bone at a joint is torn, either partially or completely. With a fall from a bike, the ligaments most likely to be torn are on the palm side of the wrist and where the fingers meet the hand. Again, this is due to the extreme backward bending (extension) of the wrist and fingers as one tries to break their fall with the arms. Pain and swelling in the affected joint are likely, but should start to subside after a few days. If pain is severe or persistent, you should see a doctor in order to rule out a fracture.
Treatment for wrist sprains could be as simple as careful observation over several weeks or splinting and activity modification to allow the ligament to heal. In severe cases, surgical reconstruction using tendon grafts may be necessary to restore optimal function.
Not all bike falls will be avoided, but there are a few things that we can do as riders to prevent injuring ourselves:
Being aware of your surroundings is paramount, which includes being able to hear approaching vehicles from the rear. Avoid listening to music when sharing the road with motorists.
When cycling with others, break up your party into groups of no more than 3 riders in line. This will help avoid a driver from squeezing you off the road in the presence of oncoming traffic.
Mountain bikers may want to reconnoiter a new obstacle or downhill challenge prior to attempting it at full speed.
Wear padded gloves to avoid skin abrasions on the hands if you fall. They also protect against nerve compression in the wrists.