As symptoms of hip dysplasia worsen, a doctor and patient may consider two categories of surgeries. The first reshapes, redirects or salvages bone in order to preserve the natural joint for as long as possible. The second, total hip replacement (THR), replaces the entire joint and is used in cases of severe pain, considerably compromised mobility and cartilage that is so worn that replacement is necessary. Many surgical procedures can prolong the amount of time before the patient needs a THR. This has several advantages:
- Using their own bone and cartilage allows for a live joint with full sensation.
- There are no activity restrictions.
- Bone is preserved rather than lost to an artificial joint.
- A proper "roof" is created so that if a THR is needed later on it should be successful.
- There is no worry about the possible effects of metal decomposition of an artificial joint for either the patient's body or a fetus, as this surgery is often performed on women of childbearing age.
Children have two surgical options: soft tissue surgery and bone surgeries, also known as osteotomies. One soft tissue surgery is open reduction. This is the surgical option for children over the age of 2 at the time of their first diagnosis, or for those whose closed reduction failed to correct the joint. In an open reduction, the surgeon cuts into the hip capsule and re-positions the femoral head. Once the hip is sutured, a spica cast is applied for 4 months or longer to stabilize the hip. Open reductions and other soft tissue surgeries like tendon lengthening are normally only an option in babies and very young children.
Once children are a little older, there are bone surgeries, including reshaping and redirecting:
- Reshaping reshapes the actual hip socket and is performed on young patients whose hips are pliable. These osteotomies include Dega, Pemberton, San Diego and acetabuloplasties.
- Redirecting is performed on older patients who no longer have pliable bone. In these cases, the surgeon repositions the socket but does not change its shape. These osteotomies include the periacetabular, spherical, triple and others.
There are also salvage procedures, like a shelf and Chiari osteotomy, in which non-articular cartilage is used to help hold the hip in place. The cartilage added in these procedures is fibrocartilage rather than true articular cartilage. In severe cases of dysplasia, avascular necrosis (AVN), in which poor blood supply leads to bone death or arthritis, can occur. In such cases, or in cases where the hip socket is misshapen or small, a shelf and Chiari osteotomy may be the only alternative. Another salvage option is an arthrodesis, or fusion, which eliminates all motion of the hip. This procedure is used mostly in young, active patients with poor cartilage.
Osteotomies can realign the weight-bearing surfaces of the joint while maintaining the natural bone. They can be performed on the pelvic bone or the thigh bone, or both. A surgery on the femoral side of the joint is a femoral osteotomy. One on the acetabulum side is a pelvic or innominate osteotomy. On the following pages, we'll look at two ostotomies that use these two approaches.
Arthroscopy is a surgical procedure often performed on the soft tissue surrounding the joint. It's a minimally invasive procedure that can postpone more invasive surgery. In some cases where the dysplasia is relatively non-advanced, arthroscopy can rule out the need for further surgery altogether. Arthroscopic surgery is a relatively short procedure, and often the patient will go home the same day.
For a patient requiring either an osteotomy or replacement/resurfacing, arthroscopy can address painful soft tissue conditions and greatly improve the health of the hip. Such conditions include:
- Loose bodies: In a joint with arthritis, the formerly smooth surface of the cartilage cracks, and pieces of cartilage can break off and float in the joint. These loose bodies cause the joint to catch. They also scratch the still-smooth cartilage.
- Torn labrum: The thick rim of cartilage around the socket can tear and partially flip itself into the joint, scratching the cartilage. Arthroscopy can trim the labral tear and stop it from damaging the cartilage.
- Synovitis: The synovial membrane, a lubricating layer of tissue, can become inflamed and cause disabling pain, requiring removal. Arthroscopy can be used to remove portions of the synovium. However, a complete synovectomy (removal of entire synovium) is not possible with arthroscopy.