Uncommon in United States, half of Dr. Angulo’s clinical patients are referrals from pediatrics to confirm hip dysplasia in babies under 5 months old. Babies after 3 months old are usually referred to an orthopaedic specialist for confirmation that their hips are growing correctly. Hip dysplasia is when the hip bone shifts up and the humeral head shifts out of the socket. The model shows that the yellow part of the humeral head has shifted out of the socket. It can be genetic or formed due to positional circumstances.
It is assumed that babies in Bolivia, and not in other countries, commonly get hip dysplasia because of the way they are positioned during the first few months. The babies are positioned with their legs side by side and wrapped tight in a blanket that goes on the mother’s back to be carried. In this erect position, the baby’s legs are straight, the humeral head faces internally and that forces the hip bones to shift externally. In contrast, American babies are usually carried in the mother’s arms with their legs spread around her side. This position allows the baby’s hips to grow properly because the hip bones are ideally opened up. It is very important to diagnose it as soonas possible to allow repositioning of the hip joint before 5 months, and even more important before 14-16 years old.
When a baby’s x-rays were brought in for review, I measured the hip angle to diagnose hip dysplasia. A line is drawn from the bottom of the pubic arch to the lateral sides of the ishium. This angle must be lessthan 24 cm to be considered healthy. A diagnosis of hip dysplasia is given when the angle is more than 24 cm.
This x-ray shows the left angle at 3o cm and the right angle at 37 cm. A diagnosis for severe hip displaysia.
When the hip is diagnosed early, treatment can correct the deformation. Treatment includes an apparatus (cost is about $11) that holds the femoral bone externally rotated with the legs spread. The apparatus (shown on left) is worn for a minimum of 3 months, 24 hours a day. After the third day, the apparatus can be taken off for 15 minutes to give the baby a shower but must be put on immediately. If the dysplasia is minor, exercises are prescribed. The exercises include moving each hip joint in 10 circles 3 times separately with each side every day until the dysplasia is gone.
Today a 5 month old baby came in and I measured 30 cm on the left hip and 35 cm on the right. In November, the patient was measured at 27 and 27 cm. Within two months the baby had grown hip dysplasia. An apparatus was given to correct the deformity. Another 7 month old came in who had a 38 cm measurement on the right side. Because the baby had gone so long without treatment, the acetabelum had grown a roof (it takes about 11 months to form) and would not allow the humeral head to be pushed back into the socket with treatment alone. In this case, surgery was the only treatment so that the acetabelum could be chipped away at to allow room for movement in the socket.
For most patients living in Bolivia’s indigenous communities, no access to pediatrics, or the Bolivian pediatric doesn’t properly diagnose nor refer thepatient to an orthopaedic specialist, the patient can go undiagnosed and untreated for many years. Going undiagnosed between the ages of 14-16 years old is the most dangerous. Bolivian doctors end up seeing patients who are well into their adult years for hip dysplasia. This is when surgery is the only option.
Hip dysplasia surgery for adults is dangerous and very invasive. If the cartilage in the hip’s acetebelum is still intact, a procedure invented by the Swiss is performed. Most likely, the hip is arthritic. That was probably the primary reason the patient even went to the doctor in the first place, and then happened to get diagnosed with hip dysplasia. When the hip is arthritic, arthroplasty is recommended to replace the arthritic femoral head and acetabelum.
Arthroplasty is very common in United States. 168,000 Americans undergo hip replacement yearly. I have done research and have viewed many hip replacement surgeries by the popular Orthopaedic surgeons (Dr. Bozic, Ries, Jergesen, Vail) at UCSF Medical Center in San Francisco, California. Patients are always pleased and the outcomes are very beneficial for the patient to continue living a normal and active life.
Hip replacement surgery involves making a large lateral incision at the hip, dislocating the hip joint, the femoral head is cut off and then the acetabelum is reamed. A plastic liner is placed in the acetabelum and a metal femoral prothesis is cemented into the hollow hole made in the femoral shaft. Finally a metal ball is attached to the femoral stem and then hip is placed back into the socket.
Last week, my uncle and aunt invited me to have dinner with them at Dr. Cruz’s house. Dr. Cruz and his family are good friends with my mom as well. I was told that Dr. Cruz was as famous in Bolivia as the other Trauma and Orthopaedic surgeon Dr. Zalles from Hospital Juan VVIII, where I was working. He greeted me with a huge hug and immediately started asking me questions. He had to leave for an emergency call but when he came back we talked about, well surgery of course!! He was one of the smartest and friendliest older man that I’d met, which made our conversation so easy.
When he started sharing his new invention for a hip replacement, our conversation just flowed because that was a topic I knew all about. I told him how I worked at The Biomechanical Testing Facility in San Francisco General Hospital. Everything just clicked and we both started scheming how I could help him bring his invention to United States. With a huge smile on his face, he invited me to his office for an interview. That smile plastered on his face the rest of the night was enough motivation for me to go all out with this project.
I went to Dr. Cruz’s office as the first part of the project. He spent an hour explaining his procedure with me. It was something I had pondered about myself so I was very interested. His procedure follows the regular steps for a hip replacement (refer above) up until the plastic liner is placed in the acetabelum. Before the plastic is placed inside, he carves a very special angled triangle into the bone superior to the acetabelum with a special drill saw. He then uses the femoral head bone that was cut off and shapes it to fit like a puzzle into the angled triangle. He either makes the triangle too small or the femoral head piece too big to purposely make a tight fit in order to initiate the like with like rule. Sometimes if the fit is tight enough, he skips using a screw to keep it stabilized. The purpose of this procedure is to make a perfect fitting superior surface for the plastic liner. His theory is that the plastic liner, which can be cemented or screwed into the acetabelum, can move and therefore cause another displacement. Some older patients that grow arthritic hip bones no longer support the screw holding the plastic liner in place and allow the liner to shift, which requires another surgery. Dr. Cruz’s invention has proven to avoid this for hip replacement patients.
Dr. Cruz’s procedure is currently being used by himself and other local surgeons in Bolivia and is titled, “Encastrado de Cruz” (Encased by Cruz). There is another doctor in New Zealand who had invented a procedure similar to his and they are currently competing for the title. Dr. Cruz plans on attending the World Congress Conference in a few months in New Zealand to try to beat his competitor. My plan is to do a research project in San Francisco, demonstrate that the procedure is worthy compared to the original one, publish the article in a medical journal and have Dr. Cruz come work with the surgeons in San Francisco. Seeing his smile again is worth all the work.
To view more photos of the procedure, click here...
Dr. Cruz
Sam's Cafe- Tiburon, California
Weekly run along Crissy Fields
Swimming near Angel Island
Weekly run along Crissy Fields
Swimming near Angel Island
Cheering at Escape from Alcatraz Triathlon
