Georg C. Perthes (1869-1927) was born in the Rhineland and educated in Freiburg, Berlin, and Bonn. When his chief, Trendelenburg, moved to Leipzig, Perthes accompanied him. Shortly after, Perthes served in the expeditionary force sent to China during the Boxer Rebellion (1900-1901). Upon his return from China he was made Professor and Director of the Surgical Polyclinic Institute in Leipzig, serving between the years 1903-1910. In 1911, he succeeded von Braunns as Professor and Director of the Surgical Clinic in Tübingen where he finished out his career. He was a busy surgeon and also wrote on vascular and chest diseases and on maxillofacial injuries and war surgery. He was one of the early exponents of the clinical use of X-rays in Germany. Through his interest in tuberculosis, he became aware of those atypical cases that he separated from tuberculous hip disease and called arthritis deformans juvenilis, his first paper on this subject appearing in 1910. In a second publication he was able to accurately describe the gross and microscopic changes in a hip obtained at autopsy.
Leonard F. Peltier, MD
In February, 1909, an 11-year-old boy was brought to the clinic because his parents had noticed a limp. Examination revealed normal hip flexion, but abduction, adduction, and rotation were completely restricted. The top of the trochanter extended one centimeter above Nelaton's line. Pain was present both with motion and pressure on the joint. The X-ray showed that our first impression, i.e., coxa vara, was incorrect. The angle of the femoral neck was completely normal; the head of the femur, instead of being round, was a truncated cone. The limitation of abduction and rotation with the preservation of flexion was the result of this mechanical relationship and further observations during the next year revealed significant signs of the onset of arthritis deformans. As a result of these first observations, our attention was directed to arthritis defor-mans in the juvenile hip joint and within one year we had seen no fewer than six similar cases.
These observations are being published because the practical significance of this affection is essentially greater than we had thought up to this time. Almost all authors who had written about juvenile arthritis deformans have emphasized this rarity. After Maydl reported the first case of this kind there have been only a few similar papers. Six years went by until von Brunn (1903) in a thorough review called attention again to this subject. More recently, each year has seen its series of new observations which can be summarized as follows: there have been 38 cases, 26 involving one hip, 12 involving both hips. Among the 26 unilateral cases 16 were male, 10 female; among the 12 bilateral cases, 5 male, 7 female. There does not seem to be a predilection for either sex. The fact that after the first case was correctly diagnosed in our clinic six more cases were seen within a year raises the supposition that similar cases seen previously were incorrectly diagnosed as coxa vara or tuberculosis of the hip.
The study of the pathologic changes on the X-rays naturally cannot be substituted for direct pathologic-anatomical examination; however, especially in the early stages it can be a valuable supplement since the pathologic anatomical material in juvenile arthritis deformans is relatively rare and is mostly from far advanced cases.
The first and most important changes are seen in the head of the femur. Among the seven affected hips in our six patients, five had deformity of the proximal femoral epiphysis although it was preserved; in the two other hips, the epiphysis had disappeared except for a slight residue. In five cases in the first group, all apparently in an early stage of the disease, the first change was flattening of the superior portion of the head of the femur. The thickness of the bony epiphysis was definitely reduced, and it was noted that this narrowing progressed over a year of followup. We also observed a flattening of the medial portion of the epiphysis. The superior and medial portions of the epiphyseal line formed an obtuse angle with one another which almost approached a right angle, and a rounded point of the femoral neck lay in this angle.
The X-ray projection in the horizontal (AP) plane does not completely reveal the three dimensional shape of the femoral head. It requires a combination of the X-ray and the examination of the patient to reveal his functional impairment. In all five of our cases flexion was limited slightly if at all while abduction, adduction, and rotation were markedly limited or completely absent. Obviously, on the basis of the limited motion and the X-ray findings, the round shape of the femoral head had changed to that of a truncated cone whose axis lay in line with the femoral neck. If one desires, one can speak of a cylindrical form, a type which is well known in arthritis deformans in older patients.
We suspect that the deformity of the head of the femur seen in our five cases and the associated functional disturbances are typical for the initial stages of this condition.
In X-rays in which the bony structure is well seen, the architecture of the bony trabeculae in the femoral neck are entirely normal. The bony trabeculae in the femoral neck on both the normal and the affected side appear to be similar as far as the epiphyseal line. In the early stages the only changes are in the proximal femoral epiphysis.
In later stages, the proximal epiphysis of the femur will, for the most part, have disappeared. In addition to bone atrophy, a disturbance of growth results in the proliferation of the epiphysis around its border. The head of the femur in our cases assumed a mushroom shape which is not unusual in cases of arthritis deformans in older age groups. Disturbances of growth similar to those seen in the head have also been seen in the greater trochanter. The head is drawn laterally onto the neck and the cavity between the rim of the head, and the trochanter becomes nearly filled in. The neck of the femur was involved in the process. It appeared to be shortened and thickened. Especially in one case, the distance between the trochanter and the joint surface was considerably shortened. It approached about half of the distance on the normal side. The femoral head had almost completely lost its normal shape. There is some increase in varus.
The participation of the acetabulum in the X-ray changes is noted in one of our most severe cases. There is enlargement of the acetabulum. The head of the femur opposes the acetabulum somewhat more laterally. It behaves like a wandering acetabulum which is seen not only in juvenile arthritis deformans but also especially after resections of the hip joint. In one of our cases, the head was badly deformed, the acetabulum appeared to be unaffected. Especially characteristic is the enormous hypertrophy of the greater trochanter which is associated with an increasing varus of the femoral neck.
Among the symptoms of this condition the two most prominent are loss of motion and the abnormal position of the greater trochanter.
It is a generally valid proposition that the loss of motion is the result of mechanical relationships which result from the incongruity of the joint surfaces and that reflex muscle spasms or joint adhesions play no role. This is obviously different from tuberculosis of the hip joint.
A review of our cases indicates that motion in the early stages is not limited in all directions but often only in one. This is in direct contrast to the findings of tuberculosis. This is the result of the fact that motion is lost because of the deformity of the head of the femur.
As a result of the partial disappearance of the femoral epiphysis, we generally note a slight elevation of the tip of the greater trochanter and a slight real shortening of the leg which is increased by the adduction contracture.
Palpation of the hip is normal except in far advanced cases with massive new bone formation in the region of the joint.
Pain is not a prominent early symptom coming on only after several months in spite of considerable deformity of the head of the femur.
In the majority of cases there is undoubtedly pain coming on for the most part after prolonged walking and sitting, and it may be referred to the knee as in tuberculosis of the hip. In our cases the pain was not severe enough to prohibit the children from attending school.
The limp observed with arthritis deformans juvenilis is especially significant. In many cases in the absence of pain it is the reason the patient is brought to the doctor.
There are several factors affecting the limp. There is the apparent shortening of the leg caused by the deformity and the real shortening due to the loss of height of the femoral epiphysis. The gait of our patients was very similar to patients with a unilateral congenital dislocation of the hip.
It is well known that Trendelenburg attributed the swaying gait in congenital dislocation of the hip to weak abductor muscles. All of our patients had a positive Trendelenburg sign. The weakness of the abductors, especially the gluteus medius and minimus in some of our cases, could be determined by palpation of the atrophic muscles.
The analogy of the symptoms of arthritis deformans juvenilis and coxa vara is obvious. Here we find loss of joint motion in only a particular direction while in the other directions it is free and painless. In both there is elevation of the greater trochanter. The differential diagnosis can only be established accurately by X-ray.
Although arthritis deformans juvenilis and congenital dislocation of the hip both exhibit a positive Trendelenburg sign and an elevation of the greater trochanter the differential diagnosis is usually not difficult. The history of arthritis deformans juvenilis is short without a previous history of a limp or difficulty of development. The elevation of the greater trochanter in the early stages is not as great as in congenital dislocation of the hip.
The differentiation of this interesting condition from tuberculosis of the hip joint is not as easy to resolve. However, for the most part in tuberculosis of the hip the motion of the joint is restricted in all directions by muscle spasms and this is not the same as restriction by bony incongruity in only one or two directions; furthermore the pain on motion and pressure on the joint present in tuberculosis is absent in arthritis deformans juvenilis.
If we attempt from this material to construct a picture of this disease, the most important fact is the constant progression of pathological anatomical changes. No cases have been observed for any length of time which were arrested at an early stage. In our patients followed for more than a year by X-ray all showed a progressive deformation without exception.
The tempo of the changes can progress at different rates in different patients. As the bony deformity progresses, there is a parallel increase in the complaints related to the functional disturbance. It appears that occasionally the disease can progress to involve the opposite hip. The involvement of other joints besides the hip joint in a patient with arthritis deformans juvenilis, with the exception of one, has not been observed. The failure of the disease to progress to involve other joints is characteristic and serves to separate it from chronic rheumatic polyarthritis.
Experience with treatment of arthritis deformans juvenilis is limited. Most commonly it has been treated by traction with rapid relief of pain. It is known that the treatment of arthritis deformans in the older patients by traction or immobilization is not effective. We saw in our cases that the limitation of motion developed in abduction
while flexion which was repeated cyclically while walking was not affected. From this came the thought that passive motion manually or with the help of a mechanical apparatus could work against the process going on in the head of the femur. Even if the process could not be arrested, we could at least hope that by molding the parts of the joint we could achieve a shape which permitted a better excursion of the joint.
We recommend that such medicomechanical therapy be supplemented by massage of the atrophic muscles, especially the abductors, and by hydrotherapy. Passive motion does not affect the joint adversely, while weight bearing can increase the deformity.
Resection can be considered when pain on walking is severe, in the late stages of the disease. The surgical remodeling of the head appears to be a rational operation (Axhausen).
When we discuss the cause of arthritis deformans juvenilis it is unfortunate that we must fall back on hypotheses, without proof. Trauma does not appear to play a significant role. We have, in our material, no findings which would suggest that arthritis deformans juvenilis is due to a static incongruity of the joint.
Bacterial inflammation may have a significant role in the etiology of arthritis deformans juvenilis.
One boy who, at 13 years of age, was seen with right sided hip joint deformity had been treated at the age of 10 weeks for osteomyelitis of the right femur. In spite of the long interval we believed the development of the arthritis deformans juvenilis in this case was probably related to his infection in infancy.
- The frequency and importance of arthritis deformans juvenilis is greater than has previously been noted.
- Trauma and improper static mechanical relationships do not appear to be significant in the etiology. Our cases of arthritis deformans juvenilis appear to be the result of bacterial infections of the hip joint during infancy which produced changes after a symptom free interval of many years.
- The first pathological changes in arthritis deformans juvenilis consists of flattening of the proximal femoral epiphysis which produces a characteristic deformity of the head of the femur. The progressive loss of height of the epiphysis can be followed by a series of X-rays. The X-rays demonstrate that there are nutritional disturbances within the deforming epiphyses which lead to areas of subchondral resorption.
- The limitation of hip motion in arthritis deformans juvenilis is the direct result of mechanically deranged joint.
- Pain is not evoked by active or passive motion of the joint nor by pressure. Pain comes on after walking for a long time and is commonly referred to the knee.
- Crepitation is noted only occasionally.
- The limp which as a rule is the first sign of the disease is like that seen in congenital dislocations of the hip or coxa vara and is due to the insufficiency of the abductor muscles.
- It is possible to confuse the diagnosis of arthritis deformans juvenilis, coxa vara, and tuberculosis of the hip joint.
- Immobilization of the joint should be avoided. Systematic passive motion and massage especially of the abductor muscles is recommended. In cases of far advanced bone change remodeling or resection of the femoral head should be considered.