Hip Dysplasia and Periacetabular Osteotomy (PAO)
Orthopaedic Faculty with this Specialization
University Orthopaedic Resources:
Q) What is hip dysplasia?
A) Dysplasia can also be referred to as developmental dysplasia of the hip (DDH), where through a child's early development, the hip socket (acetabulum) doesn't form normally. It is usually too shallow and the femoral head (ball) is partially uncovered, sometimes it can be facing more backward than forward (retroversion).
Q) What are common symptoms with dysplasia?
A) Many people, especially women, have dysplasia and don't know it until their mid to late twenties or thirties. Most of the time, people will start to get pain in the front of their hip (groin) after prolonged sitting or walking. Walking up or downhill can also be difficult. Sometimes they feel a dull ache in the groin, other times catching or popping.
Q) What happens inside a dysplastic hip?
A) Since the weight bearing surface of the acetabulum (socket) is smaller/shallow, it has to withstand more force and tends to wear out faster than if it shared the forces with more of the acetabulum. The cartilage and labrum are the cushion between the ball and socket (clear space on x-rays), and this can get damaged and start to degenerate (develop small tears and arthritis). If left untreated the majority of dyplastic hips need hip replacement (total hip arthroplasty) at some time in their life.
Q) How do I know if I need surgery?
A) Pain that is in the anterior groin (front) that affects daily activities and prevents you from doing the things you want to. Also if x-rays show dysplasia with early degenerative changes (mild arthritis) but still evidence of good cartilage, you may be a candidate for an osteotomy.
Q) Does pain correlate with dysplasia?
A) Not necessarily. Sometimes people have significant dysplasia without significant symptoms to warrant a big surgery. In those patients, we observe the hips over time with x-rays and re-evaluate their symptoms every year or two.
Q) What does "Periacetabular Osteotomy" mean?
A) "Peri" means around, "acetabular" means the hip socket, and "osteotomy" means to cut bone. Thus the surgery involves cutting out or carving around the hip socket to move it to a new and better location.
Q) What is involved in a Periacetabular Osteotomy (PAO)?
A) The surgeon goes through an incision over the front of the hip about 6-8 inches long, separating muscles to get to the pelvis, then with x-ray guidance (fluoroscopy) carefully cuts through the three pelvic bones (ischium, pubis, ilium) around the acetabulum to free it from its original position. Then holding the acetabulum in its new location, we fix it there with screws (usually 3-6) and use bone graft if needed.
Q) What other surgical options are there?
A) Sometimes if the angle made by the femur and head is too low (varus) or too high (valgus), then an osteotomy of the femur may be needed. This helps the femoral head to be in a more normal position to preserve it from wearing out. This surgery is called a proximal femoral osteotomy.
Q) Will I need a blood transfusion?
A) You may. We recycle the blood you lose at surgery and give it back to you if there is enough. But sometimes you will need a transfusion of 1-2 units after surgery. We usually like you to donate your own blood if you are able, but if not, the blood bank is very safe and we can use that.
Q) How long will I be in the hospital?
A) Usually, the hospital stay is 2-3 days after surgery.
Q) What physical therapy do I have to do?
A) Starting the day after surgery you will have Physical Therapy twice a day that includes gentle exercises, learning to sit, stand and walk with partial weight-bearing and crutches. You may take a few steps the first day around your room, and the second day out into the hallway and so on. After you leave the hospital, the only important therapy you have to do is walk, rest and let your surgery heal. We do not want formal physical therapy for the first six weeks, after that we evaluate your needs on an individual basis.
Q) What are the major risks to the surgery?
A) Blood clot: we reduce risk of this by using a blood thinner, T.E.D. hose (compressive stockings) and compression boots on your feet to increase circulation. Infection: you are given IV antibiotics before surgery, which is continued for 24 hours after, then keep a close watch of the incision for redness or drainage, especially in the groin.
Nerve Palsy: a sensory nerve called the lateral femoral cutaneous nerve is right where we do surgery. We do our best to identify it and protect it but there is a 50% chance you will have some numbness over the front of your thigh, over time sensation usually returns. There are also bigger nerves, femoral and sciatic nerves, which are deeper and can get stretched with a big correction/surgery, but this is very rare (<1%).
Failure to heal: this is also uncommon but always a concern, especially if you smoke. If the bone doesn't heal, the screws can break and the socket can move. An additional surgery to increase bone healing could be needed, but very rarely.
Q) What happens when I leave the hospital?
A) If you have family at home - you will usually need 24 hour help for a week. Or if you don't have adeQ)uate help at home, we could consider a Rehabilitation center. The final plans will be made while you are recovering in the hospital.
Q) What do I do at home while recovering?
A) For the first 6 weeks: finish taking blood thinners (aspirin for 6 weeks); wear T.E.D. hose; walk with crutches (partial weight bearing); keep wound clean.
For the next 6 weeks: transition to 1 cane or crutch as instructed by your physician until three months after surgery; may start gentle stretching or strengthening exercises; walk;
After 3 months: return to work part time or full time as tolerated (2-3 months from surgery), continue to walk, and return to gentle exercise.
After 6 months: You may return to full activity (when the bone cuts are completely healed) except for running/jumping activities. The best lifelong activities are walking, swimming, biking to preserve your hip's health.
Q) How long do I take narcotics?
A) Only as long as you need to, about 7-21 days from surgery. Be aware that sometimes anti-inflammatories (NSAIDS) can slow down bone healing, but Tylenol is not a problem.
Q) When can I drive?
A) Usually 3-4 weeks after surgery (when you're safe enough to not be at fault if you get in an accident and off narcotics).
Q) When do I see my doctor after surgery?
A) You will probably have staples and should see your doctor in 2 weeks, then again 6 weeks after surgery for x-rays, then 3 months, 6 months, 1 year, and every year or two so we can see how the hip progresses.
Q) Who do I call if I'm having problems after surgery?
A) The nurse/MA who works with your surgeon. Call the orthopedic clinic and ask for her voicemail, she will get back to you within a day (m-f) otherwise, call the orthopedic resident on-call.
Q) How long will it take to fully recover from this surgery?
A) You will be walking within a couple days of surgery, but on 1-2 crutches for 3 months, and it usually takes 9-12 months to feel fully recovered.
Q) How long will the PAO last? Will I need another surgery?
A) We hope to prolong the time between now and when you need a hip replacement (total hip arthroplasty). But the exact time in years is unknown, and based on the amount of arthritis in your hip already.
Q) What lifelong activities can I do or not do?
A) We advise patients to resume what they can tolerate, especially walking, swimming and bicycle riding. We discourage repetitive jumping, running and heavy manual labor and lifting. These activities tend to wear out your hip faster.
The information provided may be useful for patients to become more knowledgeable about their specific injury, surgery or condition. It is provided for informational purposes only, and does not replace the advice of a physician.
