Periacetabular Osteotomy

Periacetabular osteotomy is a surgical procedure that can restore proper hip joint function. This involves separating the acetabulum from the pelvic bone and repositioning it in alignment with the femoral head. By reducing pain, restoring function, and preventing further deterioration of the hip joint, this surgery can increase the lifespan of the hip joint and delay the need for total hip replacement.

This surgery can be performed on children over the age of 10 as well as adults, preferably those under 40 years of age.

Hip anatomy

The hip joint consists of a ball-and-socket structure, where the ball-shaped head of the femur connects with the acetabulum of the pelvic bone. The edge of the socket is encompassed by cartilage, forming a rim known as the labrum. The labrum helps to deepen the socket, providing stability to the joint.

The head of the femur and the acetabulum are covered with cartilage, a resilient and flexible tissue that enables smooth movement between the two bones without friction.

Hip dysplasia is a congenital condition of the hip where patients have a shallow acetabulum (acetabular dysplasia) or an abnormality in the shape of the upper part of the femur. This results in symptoms such as limping, waddling, or walking on their toes. As hip dysplasia progresses, it leads to premature degeneration of the hip joint's cartilage and may result in a labral tear or rim fracture. Patients typically experience groin pain between the ages of 20 to 30 years.

Diagnosis of hip dysplasia is based on the patient's medical history, symptoms, and a physical examination by a doctor. An X-ray of the hip joint is performed to confirm the diagnosis, and an MRI scan may be ordered to assess the condition of the labrum.

Initial treatment is aimed at managing the symptoms of pain and inflammation. Surgical treatment, such as periacetabular osteotomy or total hip replacement, is necessary for the treatment of hip dysplasia. If left untreated, hip dysplasia leads to progressive arthritis, increasing pain, and a decline in hip function.

Surgical procedure 

To provide the surgeon with continuous live X-ray guidance during periacetabular osteotomy, the technically challenging surgery is performed under Fluoroscopy.

The patient is placed under general anesthesia and positioned on their back before an incision is made over the hip joint. The acetabulum is then completely cut from the rest of the pelvis with a surgical saw. Next, the fragment of the bone containing the acetabulum is rotated to a new position, allowing it to cover the head of the femur more naturally, and then secured in the new position with screws. Finally, the incision is closed using sutures and surgical staples.

During the operation, the surgeon may determine that cutting and repositioning of the femoral head is necessary, which requires a separate incision and is known as a femoral osteotomy.

Risks and complications

Although periacetabular osteotomy is generally considered a safe surgical procedure, it is not without risks. Possible complications include bone non-union, wound infection, deep vein thrombosis, nerve damage, and pulmonary embolism.

After the surgery, patients are given pain medication and blood thinners. For the first six weeks, crutches are necessary to avoid putting full weight on the operated hip. X-rays are taken a few days after the procedure to confirm the new position of the acetabulum. Physical therapy is initiated as soon as possible to strengthen the hip muscles and improve hip function. Full recovery can take up to four months.

Compared to total hip replacement, periacetabular osteotomy has several advantages for young patients with dysplastic hips. Patients who undergo periacetabular osteotomy have no restrictions on hip movement and can lead an active life without the risk of joint dislocation. Moreover, the natural bone is preserved, which is better than an artificial joint that can wear out and potentially release metal ions, posing a risk to women of childbearing age. Additionally, periacetabular osteotomy is performed on young patients who are expected to outlive the lifespan of an artificial implant. THR can still be performed later, if necessary, but it has a higher risk of complications, and the patient would lose full sensation of the hip joint.