Varus osteotomies, for many years, have been the treatment for developmental hip dysplasia. In this patient you see the result after 11 years (Fig 1). The joint space laterally is worn-off. The weightbearing area was too small and was not covering the femoral head broad enough and horizontally.

Reorienting rotational osteotomies of the acetabulum is the more physiological way to avoid pain and osteoarthrosis. The acetabulum has to be rotated laterally and anteriorly. Then the weightbearing area can get normal angles (Fig. 2).

Many different osteotomies have been described since LeCoer 1965 and Hopf (1966) began with the first ones. They differ regarding the distance to the acetabulum and whether they release the acetabulum from the sacroischial ligaments. Our osteotomy could be placed under letter C, but it is an oblique, not a transverse osteotomy of the ischium, to maintain the bony contact after anterior rotation and avoid pseudarthroses.(Fig. 3).

In Fig. 4 and 5 you see the oblique osteotomy of the ischium ascending cranio-dorsally separating the acetabulum from the two sacroischial ligaments. This is also achieved in the periacetabular osteotomy of Ganz (Fig. 6), but only in these two. Other osteotomies can not rotate to the full extent necessary in severe dysplasia.

The chisel should be directed anteriorly no less than 10° and no more than 30° anteriorly to avoid problems (Fig. 7).

A few remarks I have to make to the measurements we used. The lateral view of Lequesne and deSeze is difficult to take exactly and to measure and is not always reliable (Fig. 8). But this radiography shows us the second plane of the hip.

During operation we also check in the image intensifier a.p. the relation of the anterior and posterior rim of the acetabulum to each other and at the end we can take a radiography of the lateral view by turning the pelvis and leg 25° anteriorly on the table.

It is essential, that we rotate the acetabulum. Levering it only laterally, would lengthen the pelvic wing. We have seen one scoliosis where one pelvic wing was longer and the other shorter after bilateral osteotomies. The rotation of this acetabulum was perfect. In the beginning we left them a bit lateral in the position, which can also cause pain and instability.

Later we rotated the lateral part of the pubis after osteotomy higher than the medial and shifted the joint medially.

In the second plane an exact rotation is necessary too. With the Schanz-screw the posterior part of the acetabulum should be rotated upwards as these figures demonstrate (Fig. 9).

The radiography is seen here (Fig. 10). The lower edge of the acetabular fragment has moved dorsally and upwards on the plane of the ischial osteoteomy.

In Fig. 11 only a levering anteriorly has been performed. This dislocates the center of the hip anteriorly and should be avoided.

In the beginning we did not realize the influence of torsional deformities of acetabulum and femur. I have to add here that Visser and Anda demonstrated that acetabular anteversion decreases with anterior tilt, that means more inclination of the pelvis, and increases with less anterior inclination than normal (Fig. 12).

Here, at the left, we see a joint in which the upper anterior margin of the acetabulum also overlaps the posterior. Anteversion is partially decreased. After operation this overlaps even more (Fig. 13).

As far as this patient is concerned, postoperatively, the anterior margin overlaps the posterior to a great extent (Fig. 14).

So with anterior rotation of the acetabulum we have to rotate 10-15 degrees internally to avoid a decrease of internal rotation of the hip. We control it on a vertically implanted K-wire in the acetabulum (Fig 15).

The technique of the operation during recent years has been changed in some ways also by my former coworker Dr. Kalchschmidt. Therefore his name should be added as an author. He does not detach the medial gluteus muscle from the pelvis any more and performs the ilium osteotomy from the inner side of the pelvis. The wire cerclage for the pubic osteotomy was given up and a screw fixation was introduced, that gives more stability (Fig. 16).

Reinvestigations were performed at different times. One contained the unselected early material operated between 1977 and 1987 and reinvestigated between 5 and 16 years. The other was initiated by my follower Prof. Katthagen on selected patients with a follow-up of mainly 10 years from the year 1988.

216 joints could be reinvestigated. 78 operations had been peformed in children and adolescents and 138 in adults.

The deformations of the joints were quite different. Therefore we introduced four grades of decentration (Tab. 1). In grade 1 the joint is fairly centered and spherical and best results can be expected. In grade 2 the femoral head is dislocated in an elongated acetabulum, but can be recentered. The false acetabulum in grade 3 has only a smaller sector and weightbearing area. But it is enlarged in the horizontal position. In grade 4 the femoral head is higher dislocated. But it can be reduced by abduction.

Our material shows high percentages of marked deformation of the hips, 26% already of false acetabula and 40-45% of the elongated acetabula. The clinical grading regarding pain, walking and patients opinion was "good" and "very good" in 85% (Tab. 2).

For the evaluation of the position of the hip joint we have earlier already introduced a score of normal values grade 1 and degrees of deviation from normal 2 to 4, which we can compare before and after operation.

We have tested these angles again regarding the presence of pain in our patients. In the angle of the weightbearing zone, the maximum of joints free of pain was 74% at the angles - 5° to + 5°, so practically the horizontal plain. The range is -10° to + 10°
(Tab. 3).

So we came to the optimal angles and the angles of overcorrection, causing also pain. This too has to be considered.

In Fig. 17 and 18 you find the correction of the weightbearing zone, the most important indicator of a normal hip similar to Bombelli. Yellow - the preoprative value, - red the postoperative - at the left in the centered joints, at the right in the elongated acetabula, there, the preoperative values were much more pathological than in the centered joints. After operation, in the centered joints 78% had grade 1, in the decentered slightly less. But this has changed later with more rotation and elevation of the tear drop figure.

In the false joints the deformation is even more accentuated before operation, and less improvement postoperatively. But this improved later too.

Interesting is a survivalrate curve regarding absence of pain, when optimal normal values of a joint and expanded normal values are compared with pathological angles in the lower curve. In the latter the remission of pain was significant.

Therefore the achievement of normal values is quite essential.

There are, however, other factors too, where we have no influence: the degree of arthrosis of a joint and the loss of sphercity of a femoral head as measured by the circles of Mose. Joints without arthrosis are free of pain in 70% (Tab. 4) and joints of Mose grade 1 and 2 are also free of pain in 71% (Tab. 5). Therefore treatment should begin with regular pain, not with the appearance of osteoarthrosis.

The results may be summarized: 74.5% of the joints were free of pain or had a continuous improvement of pain. In 82% there was no increase of arthrosis. Secondary operations were rare. Nine patients (4%) needed later a total hip when the deformations or the degree of arthrosis was too anvanced.

Let us now look at the new reinvestigation of Katthagen, Küpper et al. Here all patients operated in 1988 were followed up 10 years when the degree of decentering was only 1 and 2, the degree of arthrosis 0 and 1, the classification of Mose 0 to 2. Therefore the number of joints is only 56. For the survivalrate curve, we included joints of the opposite side when they were operated earlier or a short time later. The number of joints then came to 77.

Here I present the survivalrate curve of the early material (Fig. 20) and the 10 year follow-up of Küpper, Katthagen et al (Fig. 21). Pain was classified after the Harris groups.

No pain at all, the horizontal line on top, is his group A. In the second curve from the top, the occasional and the mild pain of groups B and C is represented, and in the lowest curve the groups D and E, the pain which is limitating function and the severe. 49% were free of pain in the first material and 39% in the second, but here the group of the occasional and mild pain was somewhat larger with 51% compared to 43% in the first material.

The 8 patients with severe pain, I was astonished to see, that they had lower lumbar pain and at the iliosacral joints. Their hip measurements were all normal. I think, this in total, are good results for a time of 10 years.

At the end, complications have to be mentioned. Katthagen established a statistics of all 251 hips operated in 1999 (Tab. 6). Pseudarthroses were found in 4.4%, mainly in the pubis (Tab. 7).

Delayed ossifications were seen in 10.8% and operated in 8.4%. Lesions of the sciatic nerve in triple osteotomy alone are listed with 2.1%, but with additional femoral osteotomy in 4.8% (Tab. 8).

This may be caused by longitudinal short traction or movement as well as retractors and should careful be avoided. At the ischial osteotomy the nerve should be left covered by the muscles. Double curved retractors are safer than sharp edged. Also the tendon of the internal obturator muscle should remain dissected, since it is a hypomochlion. Most of the lesions recovered to a great degree, but care has to be taken.

We prefer this operation because it has best possibilities to correct even severest dysplasias and deformations and the field of operation is good visible. Avascular necroses of the acetabulum have not been observed. Deliveries of babies are not impeded. With our forms of osteosynthesis the patients can walk on crutches after a few days and go home after two weeks.

A postcard almost 20 years after triple osteotomy I lately received from an air-pilot whom I had operated in 1982.

(Fig. 22 and 23) In his career he became even captain of an airbus, flying around the world. He was free of pain, had even taken part in mountain climbing in Bolivia and the Himalya montains and played tennis. This is astonishing since the joint was already somewhat decentered, but the weightbearing surface was large enough and could be brought into the horizontal position. This gives us hope for longer positive survivalrate curves in the future.

A short report now on the results: One reinvestigation of the first material, operated between 1977 and 1987, evaluated 216 joints with a follow-up of 5-16 years, mean value 7.7 years and was published in 1994 in the JPO, part B. The main result: In 77% of the joints continous improvement of pain. And: No new appearance and no deterioration of present osteoarthritis in 82%. This appears as a very promissing result.

The clinical results in a grading of Tschauner (Tab. 9) are very good and good each in 42% (Tab. 10).

The degrees of deviation from normal, pre- and postoperatively in the angle of the weightbearing zone, that should be around zero in grade 1, are seen here; at the left for the centered joints and at the right for the elongated acetabuli with a decentered femoral head (grade 2 of decentration). In the centered joints 78% had a normal horizontal coverage, in the decentered 51%. But this was in the beginning (Fig. 17 and 18).

With Küpper and Katthagen, 77 joints of 56 patients, operated in 1988, were completely reinvestigated after 10 years, some a few years later, when the opposite side was already operated. However we selected only grade 1 and 2 of decentration and osteoarthrosis and 2 grades of Mose.

In these survivalrate curves of the ealier material (Fig. 20) and the newer of 1988 (Fig. 21) , the critical event was a new onset pain according to 3 groups of the Harris score. The upper transverse lines present joints without pain. The next curves in the middle, with many stairs, contain joints with only occasional or mild pain. Finally the short, very steep curves underneath, belong to patients with moderate and severe pain.

Only 8 joints of 77 represented this group. The joint measurements of these patients were normal, but 3 of them had at both operated sides pain at the iliosacral joints, and 2 at one side. One complained of sciatic and lumbar pain and another had a scoliosis.

Three things we cannot change with our acetabular rotation, which are responsible for at least a slight pain over the years. At first, the grade of osteoarthrosis, that is already present, secondly a deformation of the femoral head, measured with the concentric circles at 2 mm distance of Mose. As you see (Tab. 4), with grade 0 of arthrosis almost 70% of the joints are free of pain. 71% are also free of pain, if there is no deformation of the spherical femoral head (Tab. 5).

And the third point is the acetabulum in its inner spherical form and size, which we cannot change, either when it is a false joint with a too short socket as in Fig. 24 when the acetabulum is elongated and flat up to this case. But the weight- or loadbearing area - is anyway enlarged and the patients feel even in such cases a relief after operation. For a total hip later the conditions were improved too.

For this relief one last example: acetabular rotation of a false joint in a 22 year old woman (Fig. 24) in 1981.

10 years later, at the age of 32 years, she had more signs of arthrosis, but was still content with her condition and did not want a total hip.

Triple pelvic osteotomy, if perfectly performed in all 3 planes, can relieve pain fully or partial and postpone arthrosis in a great number of hips, for how long, we have still to see. Spherical, congruent joints, of course, have the best expectation. With less congruity we have to wait, whether the pain increases or stays moderate for a longer time.