Protrusio acetabuli refers to a protrusion of the femoral head and acetabulum toward the lesser pelvis. It can be congenital or result from certain diseases.
What is protrusio acetabuli?
In medicine, we speak of a protrusio acetabuli when the acetabulum and femoral head bulge toward the lesser pelvis, which doctors refer to as protrusion. This results in restricted movement of the hip in all directions. If the protrusion appears on only one side of the body, leg shortening is possible. Protrusio acetabuli often appears in the context of various diseases, among which is Marfan syndrome. This condition is a connective tissue disorder caused by a gene mutation. The protrusion of the acetabulum was first described in Breslau in 1824. According to studies, about one third of all Marfan syndrome patients suffer from protrusio acetabuli, affecting both hip joints. Protrusio acetabuli is also known as the Otto Chrobak pelvis. It was named after the German anatomist Adolph Wilhelm Otto (1786-1845) and the Austrian gynecologist Rudolf Chrobak (1843-1910). Physicians distinguish between a primary as well as a secondary protrusio acetabuli. In the primary form, there is said to be a dominant inheritance. It is primarily seen in women. The secondary form is called protrusio acetabuli, which is caused by different hip diseases. It is recorded in equal proportions in both sexes.
Causes
Causes of protrusio acetabuli include osteomalacia, coxarthrosis, Marfan syndrome, fibrosis dysplasia, and Paget’s disease (osteodystrophia deformans). In some cases, trauma or hip TEP implantation are also responsible for protrusion of the acetabulum. In principle, protrusio acetabuli is a prearthrotic deformity. As a result, the femoral head sinks into the acetabulum. The transition to the pathological form is fluent. People over 30 years of age are particularly affected by protrusio acetabuli. If the protrusion is already apparent in childhood, a serious course is imminent.
Symptoms, complaints, and signs
In the early stages, protrusio acetabuli still progresses without symptoms. This is also the reason why the disease is often detected so late. Even in the advanced stage, not every patient experiences painful symptoms. In some patients, the change in shape causes secondary signs of wear, with cartilage abrasion and deformation of the femoral head. In such cases, the term protrusion coxarthrosis is used. This refers to a protrusion arthrosis of the hip. In the further course of protrusio acetabuli, movement restrictions at the hip joint become increasingly apparent. Initially, this involves movements such as abduction, extension and rotation. Later, affected individuals suffer from pain even at rest, especially at night. In addition, they are no longer able to walk without pain. Even complete stiffening of the hip is possible. In women, there is also a risk of narrowing of the small pelvis, which in turn results in mechanical disabilities. This can have a negative effect on the birth process in the event of childbirth.
Diagnosis and course of the disease
Diagnosing protrusio acetabuli is not always easy. This is especially true if it runs free of symptoms, so that it can usually only be discovered by chance. If, on the other hand, typical symptoms occur, these are considered an indication of the protrusion. One of the most important examination methods is the taking of X-ray images. On the radiographs, the physician can see the recess of the acetabular base in the direction of the pelvis. X-ray examination criteria include a change or loss of the so-called Köhler’s tear figure. Crossing of the internal pelvic line over the hip joint line and increase in the center-kerf angle are also considered for examination. The course of protrusio acetabuli depends on its extent. Thus, in some cases, it may be necessary to replace the damaged hip joint with an implant.
Complications
Due to protrusio acetabuli, affected individuals suffer from discomfort in the hip.However, these complaints do not have to be associated with pain in every case. In most cases, the disease is therefore also diagnosed late, because the symptoms are not clear or occur only in a very mild form. Furthermore, however, the patient’s hip is severely worn down by protrusio acetabuli. As the disease progresses, pain may occur without treatment. Especially at night, the pain can be very uncomfortable, leading to sleep problems or depression. Restricted movement is also not uncommon due to protrusio acetabuli. Stretching and extending the entire body is significantly limited due to the disease. Treatment of protrusio acetabuli is not associated with complications. In most cases, the symptoms of the disease can be limited with physiotherapy measures. It also does not affect or reduce the patient’s life expectancy. However, in severe cases, affected individuals rely on surgical intervention to continue moving around.
When should you see a doctor?
In any case, the disease protrusio acetabuli must be treated by a doctor. It otherwise comes to various complications and also does not heal itself, so the treatment of the disease is essential. The earlier the doctor is consulted in case of protrusio acetabuli, the higher are the chances of complete healing. As a rule, protrusio acetabuli is not manifested by any particular complaints or symptoms, so unfortunately the disease is diagnosed and treated much too late. Therefore, early treatment is usually not possible. In this case, the affected person suffers from movement restrictions at the hip joint. Therefore, if these restrictions occur, a doctor should be consulted immediately. In some cases, pain also occurs, which can also be accompanied by pain at rest. Especially at night, this can lead to pain and thus to sleep problems. Protrusio acetabuli can be diagnosed by a general practitioner or by an orthopedist. However, the treatment depends strongly on the exact manifestation and the type of disease, so that no general prediction can be made here.
Treatment and therapy
The treatment of protrusio acetabuli can be performed both conservatively and surgically. Which therapy is ultimately most appropriate depends on the stage of the protrusion and what symptoms the patient is suffering from. If there is no pain, the patient usually waits. Thus, secondary coxarthrosis does not necessarily occur in everyone. In principle, an X-ray examination is recommended every two years to monitor the further progression of protrusio acetabuli. If the patient suffers from pain, this is initially combated with conservative means. These may include the administration of painkillers, physiotherapeutic treatments such as physiotherapy exercises, hydrotherapy or electrotherapy. Weight loss and the use of orthopedic aids such as walkers or buffer heels are also considered important. In addition, the patient should move the hip joint slightly. Despite relief of symptoms, conservative therapy cannot prevent protrusio acetabuli from progressing. If the pain worsens as well as the movement restrictions, surgery is often necessary. In children, there is still the possibility of closing the growth plates. In adult patients, the insertion of an artificial hip joint is often advisable. In this way, the long-term results are considered excellent. Problems may possibly exist due to a thinned-out acetabular base, which makes it difficult to anchor the artificial acetabulum in the joint. In such cases, plastic reconstructive treatments take place, mostly using the patient’s own bone.
Prevention
Preventive measures against protrusio acetabuli are not known. Thus, the condition is sometimes already congenital.
Aftercare
Affected patients usually have only a few and also only limited measures of aftercare available for protrusio acetabuli. For this reason, patients should seek medical attention at the first symptoms and signs of the disease to prevent further complications. As a rule, there can be no independent healing, so that the affected person is dependent on a medical examination and treatment.The earlier a doctor is consulted, the better the further course of the disease usually is. The treatment depends strongly on the severity of the protrusio acetabulis, so that no general course can be given. In most cases, patients are dependent on taking various medications, whereby attention must be paid to the prescribed dosage and also to regular intake. If there are any uncertainties or side effects, a doctor should be consulted first. Regular check-ups by a doctor are also very important. If the disease is treated by surgery, the affected person should take it easy after the procedure, especially protecting the affected region.
What you can do yourself
The discomfort caused by protrusio acetabuli can be alleviated with consistent physiotherapy, which noticeably reduces the pain. In everyday life, it is important to interpret the physical signs and assess the pain. The sooner the disease is diagnosed, the better the chances of recovery. However, the difficulty in recognizing the symptoms means that the diagnosis is often made very late. To reduce problems, it is advisable to reduce weight. Orthopedic aids are also available. The use of walking aids or special buffer heels mitigates the restrictions in everyday life. Targeted physiotherapy and light movements of the hip joint reduce the pain level. At the same time, the advancing wear and tear process slows down. However, the progress of hip disease cannot be stopped, only delayed. Patients should talk to their doctor about the possibility of surgery. Depending on the situation, this intervention can significantly improve the quality of life. Especially in sensitive individuals, the pain and discomfort often lead to psychological problems. In such cases, psychotherapeutic care should be provided in addition to physiotherapeutic measures. In some cities there are self-help groups for osteoarthritis patients who feel understood. The exchange helps to deal with the situation better.
