It’s a common question we hear: can hip replacement surgery correct a leg length discrepancy? The short answer is yes, but it’s not quite that simple. Here’s what you need to know about leg length discrepancy and hip replacement surgery.
Hip replacement is a surgery to replace the hip joint with an artificial one. It’s a treatment option for severe hip pain and hip dysfunction. The goal of hip replacement is to relieve pain, help the hip joint work better, and improve walking and other motions.
There are two types of hip replacement: total hip replacement and partial (unicompartmental) hip replacement. In a total hip replacement, the damaged bone and cartilage is removed from your hip joint and replaced with an artificial joint usually made of metal and plastic components. In a partial (unicompartmental)hip replacement, only the damaged cartilage is removed and replaced.
Hip replacement surgery is usually done when other treatments haven’t worked to relieve your pain or improve yourfunction, or when you have arthritis in your hip that has caused major disability.
What is leg length discrepancy?
There are two bones in the lower leg — the tibia, which is the larger of the two, and the smaller fibula. These bones are connected at the knee by a joint called the tibiofibular joint. The tibia and fibulum also meet at the top of the ankle in a joint called the talocrural joint.
The two bones are held together at these joints by ligaments (bands of tissue that connect bone to bone). The ligaments allow some movement but they also provide stability.
The muscles and tendons around these joints also help to stabilize the bones. The muscles themselves attach to the bones through strong bands of tissue called tendons.
In a normal healthy leg, all of these structures work together to allow us to walk, run, and jump without pain or discomfort.
However, sometimes either due to an injury or congenital condition (present at birth), there can be a discrepancy in the lengths of the two bones in the lower leg. This is called leg length discrepancy (LLD).
Causes of leg length discrepancy
There are a number of different causes of leg length discrepancy, which can be divided into congenital (present from birth) and acquired causes.
Congenital causes include:
Hemihypertrophy – one side of the body grows faster than the other. This can be due to a growth hormone imbalance, or an genetic condition such as Fibrodysplasia Ossificans Progressiva.
Limb length discrepancies may also be caused by partial or complete absence of a limb. This can occur due to a birth defect known as hemimelia, or following amputation of a limb.
Acquired causes include:
Bone fractures – if the bones in the leg are broken in separate accidents and heal at different rates, this can lead to a limb length discrepancy. This is more common in children, as their bones are more pliable and easier to break than adult bones. Over time, the Post-Polio Syndrome can also lead to limb length discrepancy, as the polio virus attacks and weakens muscles on one side of the body more than the other.
How is leg length discrepancy treated?
There are a number of ways to treat leg length discrepancy, depending on the cause and severity of the condition. In some cases, no treatment is necessary. For example, many children with mild discrepancies (less than 2 centimeters) do not require treatment. Instead, they may be monitored over time to see if the discrepancy increases.
If leg length discrepancy is due to a structural problem in the bones or joints, your child’s doctor may recommend one or more of the following treatments:
- Epiphyseodesis. This procedure involves surgically fusion of the growth plate to the bone above or below it. This essentially “turns off” the growth of that bone, allowing the other bone to catch up. Epiphyseodesis is typically performed when discrepancies are significant (greater than 4 centimeters) and still growing. It’s also occasionally used for cosmetic purposes or to alleviate pain associated with LLD.
- Limb lengthening. During this procedure, cuts are made in the bones of the shorter limb and an internal or external device is used to gradually pull these bones apart (lengthen them). New bone forms between the gaps created by this process, eventually leading to equalization of limb lengths. Limb lengthening can be performed at any age but is most often done between ages 5 and 9. The surgery can take several months to complete, and your child will need crutches or other devices during this time. There’s also a risk of complications, such as infection and nerve damage.
- Osteotomy. This procedure involves cutting and reshaping bones in order to correct limb length discrepancy. It’s usually performed on children who have stopped growing (usually around age 11 or 12) and have a small discrepancy (2 centimeters or less). Osteotomies can be performed on either the upper or lower limbs; however, they’re most commonly done on upper limbs.
Can hip replacement correct leg length discrepancy?
It is possible that hip replacement surgery can correct a leg length discrepancy, depending on the cause of the discrepancy and the type of hip replacement surgery being performed. If the discrepancy is due to a difference in the length of the bones in the legs, hip replacement surgery may be able to shorten or lengthen the bones to even out the difference. However, if the discrepancy is due to a problem with the muscles or joints around the hip, surgery may not be able to correct it.
Risks and complications associated with hip replacement
Many people report excellent outcomes after hip replacement. In fact, most people who have this surgery are able to relieve their pain and regain their mobility. However, as with any surgery, there are some risks and complications associated with hip replacement.
The most common complication is infection. This can occur at the site of the incision or in the joint itself. Other potential complications include:
-Dislocation of the implant
-Loosening of the implant
-Hip joint stiffness
-Failure of the implant
Recovery after hip replacement
After having a hip replacement, you will need to spend time recovering in the hospital. The length of your stay will depend on how well you are doing and how quickly you are able to progress through physical therapy. Once you are able to walk with a cane or walker and take care of yourself, you will be able to go home.
You will likely need to use a walker or cane for several weeks after going home. Your surgeon will let you know when it is safe for you to stop using these devices. Recovery times vary from person to person, but most people can expect to return to their regular activities within 3-6 months.
It is important to follow your surgeon’s instructions during your recovery in order to ensure a successful outcome. One potential complication after hip replacement is leg length discrepancy. This condition can be corrected with additional surgery, so it is important to keep your surgeon updated on your progress and alert them of any problems.
While a hip replacement can sometimes help to correct a leg length discrepancy, it is not always successful. In cases where the discrepancy is minimal, it is more likely that the hip replacement will be successful in correcting the issue. However, if the discrepancy is significant, there may be still be a noticeable difference after the surgery.