Hip and Femur Injuries
Injuries to the hip and femur, are very common injuries that your COA doctor is very familiar treating. While your active toddler can break his femur from a simple fall on a slippery floor, as he gets older and the bone gets stronger, a much higher force (such as from a car accident) is necessary to break his femur.
Hip and Femur (Thigh) Anatomy:
The hip joint is the connection between the pelvis and the femur bone. The pelvic portion of the hip joint is known as the acetabulum, while the portion of the femur that contributes to the hip joint is the femoral head and neck. It is a ball and socket joint similar to the shoulder. Because of the ball and socket joint structure, the hip has an extensive and circular range of motion that allows us to perform our daily activities such as walking and climbing stairs, but also allows us to perform other activities where this range of motion is necessary - such as with gymnastics, skating, hockey, and soccer. Whereas the shoulder joint relies on the muscles and tendons surrounding it for it to be stable, the hip joint gains its stability on its bony articulation with the pelvis.
The femur bone has various nomenclature from top to bottom, and this includes the head and neck of the femur which articulates with the pelvis, the shaft of the femur, which is the long tubular portion in the middle of the bone, and the distal (or bottom) of the femur. The growth area at the distal femur (known as the physis) is responsible for 70% of the growth of the femur bone, and therefore, injuries to this area are concerning for future growth problems.
The pelvis and femur are two of the strongest bones in the body, and the muscles surrounding this area are also amongst the strongest. Some of the more familiar muscles around the hip joint and femur are the quadriceps muscle in the front, which functions to flex the hip and extend (straighten the knee), and the hamstrings in the back which function to extend the hip and flex the knee. Other important muscles about the hip include the gluteal muscles which also allow the hip to move out to the side (abduction), and the iliopsoas muscle which is one of the main hip flexors.
ACUTE HIP AND FEMUR INJURIES
If your child happens to sustain a hip fracture, this does not mean that your child has osteoporosis. In fact, these injuries are quite rare in children because their bones are often very strong. There are typically only two circumstances in which a child can sustain a hip fracture:
1. a high-energy injury such as a motor vehicle collision or being hit by a car
2. a low-energy injury in which the fracture occurs through a weak portion of the bone, usually a bone cyst
The more common type of hip fracture (as pictured here) occurs through a portion of the femur bone that has a rich blood supply. They typically occur through a benign bone cyst that can occur in children. Many times, these fractures are fixed with a plate to allow your child to be up on their feet quickly after surgery.
The less common type of hip fracture occurs near the head or neck of the femur bone. This is truly an emergent situation. The danger results from the blood supply to the bone being temporarily compromised. Although not proven, some believe that if the fracture is fixed early, it may decrease the chance that the blood supply is lost from the bone permanently. Therefore, in certain situations, your doctor may fix this type of fracture in the middle of the night.
In the case of all hip fractures, your physician will want to follow your child for a long time after the fracture – at least eighteen months. This is because it may take a long time for the loss of blood supply (known as avascular necrosis) to occur and/or, it may take a long time, but it is quite possible for a bone cyst to reoccur.
Femur (Shaft) Fractures:
Femur fractures are extremely common in children. The treatment is based upon the age and size of your child, as well as the location of the fracture.
In general, if your child is four years old or younger, then your physician will likely recommend a treatment in a cast. This type of cast is known as a spica cast (as pictured here). This cast starts near the nipple line, and extends the entire length of the fractured limb, and then the entire length or half the length of the other limb.
Spica casts are applied in the operating room with your child completely asleep to prevent any discomfort to the child and so the surgeon can better manipulate the large cast. Once the cast is on and your child wakes up from anesthesia, usually they can be discharged from the hospital and go home the same day. It may be necessary to make some modifications like adding straps to your car seat and possibly using a wheel chair if your child is too big to fit in a stroller. The hospital case managers will assist in getting this equipment prior to discharge from the hospital.
Most children are treated in a spica cast for a femur fracture for a total of six weeks. Once the cast is removed, your child may experience:
- Stiffness and perceived pain
- Inability to walk for a few days to a few weeks
- Walking with a limp for a few months
- Rash on the skin where the cast was removed
For children five years of age and older, the treatment of the femur fracture is more dependent on the location of the fracture and the size of the child. Often, the surgeons at Children's Orthopaedics of Atlanta use flexible rods to line up the broken ends of the femur fracture. These rods are inserted into the femur bone near the knee. The surgery is fairly minimally invasive and most children recover quickly. However, your child will need another surgery to remove the rods, usually nine to twelve months after the injury.
Other times, a plate is used to fix the fracture. And then less commonly, a rod may be placed from the top of the femur bone and go all the way down, similar to how adults are currently treated.
Femur Physis (Growth Plate) Fractures:
Fractures can occur in either the proximal (top) physis or the distal (bottom) physis. Both are concerning for different reasons. Fractures of the proximal femoral physis are much more rare. The proximal physis is located between the head and neck of the femur bone. As this growth area only contributes 30% of the growth of the femur, the concern to an injury in this area is not as much a loss of ultimate height, but more importantly, a permanent loss of blood supply to the hip joint. As mentioned in hip fractures above, fractures to this area are concerning for a complication known as avascular necrosis.
A relatively common problem amongst primarily obese children is a problem known as a slipped capital femoral epiphysis (SCFE). It is typically not due to an acute injury, but pain develops gradually over time. If your child has been diagnosed with a SCFE, or you are concerned for this problem, please click here for more information.
Fractures to the distal femur require a great amount of force to occur. They typically occur from a direct blow to the area, such as with a soccer collision, football tackle, or getting hit by a car. Since this portion of the femur contributes 70% of the growth of the femur, injuries to this area are concerning for permanent growth problems. The risk of growth probelms increases with the severity of injury. In general, approximately 50% of children may suffer from some type of growth problems. If only a portion of the growth area continues to grow, while another does not, the concern is not only for a difference in limb length differences when your child is fully grown, but also for an angular deformity, where the bone grows crooked.
If your child has been diagnosed with this type of fracture, and you have not been evaluated since the initial treatment, it is probably time to get checked once again. Please call us at 404-255-1933 for an appointment, or request an appointment online.
An apophysis is a normal outgrowth of the bone that has its own seperate bony growth area that later fuses to the larger native bone during growth and devlopment of your child. An apophysis serves as a site of attachment for typically very important tendons or ligaments in the body. While your child is growing, the apophysis represents a site vulnerable to injury prior to its fusion to the native bone.
The most commonly injured apophyes (whether acute or chronic) in the hip and knee include the tibial tubercle (the outgrowth at the top of the tibia bone where the patella tendon inserts for knee extension), the anterior superior and inferior iliac spines, and the ischial tuberosity. These injuries occur when these strong tendons have a sudden contracture, such as during a sporting activity, and this force breaks the apophyseal attachment from the rest of the bone.
To read more about tibial tubercle fractures, click here, while if you are concerned for an apophyseal injury of the hip, please click here.
If you are under the belief that your child needs needs the medical attention of our COA experts, please do not hesitate to call us at 404-255-1933 for an appointment.