Common Hip Injuries
Fracture of the Pelvis
The pelvis is a ring-like structure of bones at the lower end of the trunk. The two sides of the pelvis are actually three bones (ilium, ischium, and pubis) that grow together as people age. Strong connective tissues (ligaments) join the pelvis to the large triangular bone (sacrum) at the base of the spine. This creates a bowl-like cavity below the rib cage. On each side, there is a hollow cup (acetabulum) that serves as the socket for the hip joint.
Many digestive and reproductive organs are located within the pelvic ring. Large nerves and blood vessels to the legs pass through it. The pelvis serves as an attachment point for muscles that reach down into the legs and up into the trunk of the body. A pelvic fracture is often associated with substantial bleeding, sensory and motor dysfunction, and other injuries.
How it happens
Growing teens, especially those involved in sports, are one group of people at risk for a particular type of pelvic fracture. Many "pulled muscles" may actually be undetected avulsion fractures of the pelvis. These fractures usually occur with sudden muscle contractions. A small piece of bone from the top of the hipbone is torn away by the muscle. This is a very stable type of fracture. It does not involve the entire pelvic ring or injure internal organs.
Another group at risk for pelvic fractures is elderly people with osteoporosis. An individual may fracture the pelvis during a fall, such as when getting out of the bathtub or descending stairs. These injuries usually do not damage the structural integrity of the pelvic ring, but may fracture an individual bone.
However, most pelvic fractures involve high-energy forces, such as those generated in a motor vehicle accident, crush accident or fall. Depending on the direction and degree of the force, these injuries can be life-threatening.
A broken pelvis is painful, often swollen and bruised. The individual may try to keep the hip or knee bent in a specific position to avoid aggravating the pain. If the fracture is due to trauma, there may also be injuries to the head, chest or legs. There is usually considerable bleeding, which can lead to shock. Summon emergency assistance. The injuries must be stabilized and the individual taken to a trauma center for definitive care. All pelvic fractures require X-rays, usually from different angles, to show the degree of displacement to the bones. A computed tomography (CT) scan may be ordered to define the extent of other injuries. The physician will also examine the blood vessels and nerves to the legs to see if they have been injured.
Stable fractures such as the avulsion fracture experienced by an athlete will normally heal without surgery. The physician may prescribe a painkiller (analgesic). The patient will have to use crutches or a walker, and will have to avoid putting weight on the hip until the bones heal. Because mobility may be limited for several months, the physician may also prescribe a blood thinner to reduce the risk of blood clots forming in the veins of the legs.
Pelvic fractures that result from high-energy trauma are often life-threatening injuries because of the extensive bleeding. In these cases, doctors may use an external fixator to stabilize the pelvic area. This device has long screws that are inserted into the bones on each side and connected to a frame outside the body. The external fixator allows surgeons to address the internal injuries to organs, blood vessels, and nerves. What happens next depends on the type of fracture and the patient's condition. Each case must be assessed individually, particularly with unstable fractures. Some pelvic fractures may require traction; for others, the external fixator may be sufficient. Unstable fractures may require surgical insertion of plates or screws of a biocompatible metal.
Hip fractures are a serious health problem common among elderly men and women who fall in their own homes. In 2003 there were about 345,000 hospitalizations for hip fractures (Source: National Center for Health Statistics; Centers for Disease Control and Prevention; 2003 National Hospital Discharge Survey). Only one in four patients recover completely.
A hip fracture is a break near the top of your thighbone (femur) where it angles into your hip socket. When you break your hip, it usually hurts too much to stand and your leg may turn outward or shorten. In most cases, you need hospitalization and surgery. Get to your doctor or emergency room right away.
Your doctor will X-ray both of your hips to determine exactly where the bone broke and how far out of place the pieces have moved. If the fracture does not show up on X-rays, you might also get an MRI (magnetic resonance imaging) scan. Most hip fractures are one of two types:
- Femoral neck fractures are 1-2 inches from the joint.
- Intertrochanteric fractures are 3-4 inches from the joint.
Surgery and early mobilization
Modern treatment for a hip fracture aims to get you back on your feet again as soon as possible while your broken bone heals. (Treatment may vary for certain elderly people who were already bedridden, have other complicated medical conditions and are not in much pain.) Your doctor will reposition the fracture and hold it in place with an internal device.
- Femoral neck fracture: Pins (surgical screws) are used if you are younger and more active, or if your broken bone has not moved much out of place. If you are older and less active, you may need a high strength metal device that fits into your hip socket, replacing the head of your femur (hemiarthroplasty). In some patients, a total hip replacement is the best option.
- Intertrochanteric fracture: A metallic device (compression screw and side plate or hip nail) holds the broken bone in place while it lets the head of your femur move normally in your hip socket.
Your doctor will tell you when you should start standing and walking again after surgery. You will probably need crutches, a walker or other help. You may need to do physical therapy or rehabilitation exercises to get back to your normal level of activity.