A pelvic osteotomy for acetabular dysplasia is a surgical procedure to alter the shape and depth of the bony cup that houses the femoral joint. This aims to improve function and reduce hip inflammation and pain.
An osteotomy is a surgical procedure that involves cutting and reshaping of a bone. A pelvic osteotomy is a means by which the hip is stabilized. This aids in preventing early osteoarthritis in patients with acetabular dysplasia. A pelvic osteotomy is performed to reshape a shallow hip socket to accommodate the ball of the hip joint (femoral head).
Anatomy of the hip joint
The hip joint is a ball-and-socket joint. The hip joint is formed where the thigh bone (femur) meets the pelvis. The femur has a ball-shaped head on its end that fits into a socket formed in the pelvis that is called the acetabulum. Large ligaments, tendons and muscles around the hip joint hold the bones and the joint in place and prevent it from a dislocation.
Why is a pelvic osteotomy performed?
The goals of a pelvic osteotomy are to eliminate hip irritability and instability and minimize the chances of a further hip joint degeneration.
A pelvic osteotomy is indicated in various hip disorders such as developmental dysplasia of the hip involving an acetabular dysplasia and a dislocation, avascular necrosis (bone death) such as Legg-Calve-Perthes-Disease and neuromuscular hip instability. A pelvic osteotomy can reduce the load by enhancing the contact area between the femoral head and acetabulum. It also helps to improve the femoral head coverage by correcting the defect in the acetabulum.
What is an acetabular dysplasia?
An acetabular dysplasia, also called hip dysplasia, is a disorder that occurs when the acetabulum is shallow and does not provide sufficient support to the femoral head causing instability of the hip joint. Over time, this instability causes damage to the labrum (a ring of fibrous cartilage around the edge of the joint surface of a bone) and cartilage lining of the joint, which can result in pain and development of early hip osteoarthritis.
An acetabular dysplasia can be a result of developmental dislocation of the hip that was treated in infancy or childhood. Therefore, children treated for hip dysplasia should be closely followed by a physician until their bones are fully grown. An acetabular dysplasia can exist as a mild issue that can take years to decades for symptoms to develop. Patients who have been diagnosed with an acetabular dysplasia often have a family history of early hip osteoarthritis or hip dysplasia.
- Patients with an acetabular dysplasia present with
- pain in the hip or groin,
- feelings of instability or “giving way” of the hips,
- change in gait and
- hip dislocation.
How is a pelvic osteotomy performed?
Symptomatic medical therapy, muscle-strengthening exercises and weight-relieving exercises can be provided until the surgery and can be continued thereafter.
The surgery is performed under general anesthesia.
Pelvic osteotomies can be categorized into three types based on the surgical technique:
Redirectional, reshaping and salvage/augmentation osteotomies.
- Redirectional osteotomies: These alter the orientation of the acetabulum.
- Reshaping osteotomies: These are involved in changing the shape and volume of the acetabulum.
- Salvage or augmentation osteotomies: These aim to improve the coverage of the defective femoral head.
What are the complications of pelvic osteotomies?
Like any major surgery, there are complications encountered during a pelvic osteotomy such as
- injury to the nerves and blood vessels,
- pain, swelling and bruising,
- bleeding,
- infection,
- damage to the structures forming the joint,
- delayed union between bone grafts and
- heterotopic ossification (formation of the bone in abnormal sites, usually in the soft tissues).