The hip is deep articulation covered by a very powerful muscular apparatus that is burdened with the job of assuring stability and correct mobility. The surgeon who approaches the hip finds himself confronted with a dilemma : make an large enough exposure in order to implant a bipolar prosthesis and at the same time preserve the Gluteus musculature in order to avoid the instability of the arthroplasty, permitting the patient to recover his mobility as quickly as possible.

Surgeons have been blessed with a great deal of imagination concerning the numerous possibilities of accessing the hip. We will look at four approaches that are largely practised: Hueter approach, the lateral approach, the trochanterotomy and the classic posterolateral approach.

THE HUETER APPROACH :

It is the most anterior approach for penetrating the hip. The incision descends the anterior iliac spina in direction of the fibula head for a dozen centimeters. In his incision the surgeon leaves behind all the Gluteus muscles. In front, he leaves the rectus femoris then ties the anterior circumflex artery before encountering the iliopsoas muscle, that maintains a close relationship with the articulation, before ending at the lesser trochanter.

This approach by Hueter(The Hueter approach) has the advantage of being particularly anatomic. It does not touch the gluteus medius muscle and the operational follow-ups are in general very simple and rapid. However, it does require a special type of orthopedic table and its perfect realisation demands experienced hands.

A lesion of the cutaneous femoro nerve is not rare. This leads to a deficiency in the anterior external thigh face that is only a problem of sensitivity.

Rehabilitation:

The return to mobility is rapid. Dislocations are exceptional and occur only in the case of « extension with a outward rotation». In general, prevention of posterior dislocations is unnecessary. Crutches are rapidly abandoned between the second and third week. However, for the first five weeks, in order to prevent a tendinitis of the gluteus muscles, the patient should use a cane whenever he goes out.

THE HARDINGE OR DIRECT LATERAL APPROACH

The Hardinge approach can also be considered as an anterior approach because one must place the inferior limb in external rotation in order to obtain the dislocation of the hip. The incision is external with regard to the greater trochanter. After having vertically open the fascia lata, the surgeon discovers the greater trochanter. Attached to its upper part is the gluteus medius. To the lower part of the greater trochanter is inserted the vastus lateralis.

The valve created, the surgeon pushes it forwards with a spreader. The opening of the capsule and the section of the neck gives access to the cotyloid cavity.

At the end of the intervention, the reinsertion of the gluteus medius will be solid and effective because the anterior part of the gluteus medius is attached to the vastus lateralis muscle by a digastric neotendon (digastric tendon : tendon connecting two muscular bodies between each other).

Rehabilitation:

This approach has seduced many surgeons because it causes very few dislocations. The prevention of dislocations is legitimate but is less strict than with a posterior external approach. The patient must however use his canes 35 days - just until the complete cicatrization of the digastric tendon. There after the patient uses a cane for two months only when he goes out.

THE EXTERNAL APPROACH WITH TROCHANTEROTOMY

The patient is installed in lateral decubitus taking great care that all of the anterior iliac spina is place on the same plane.

The incision cut is identical, a length of about twenty centimeters, external, slightly incurved towards the back in order to follow the direction of the buttock fibers.

The aponeurosis of the fascia lata is cut. The incision grows longer up into the fibers of the large buttock which are isolated longitudinally. Once the two lips of the muscoloaponeurotic are separated, the deep planes appear. The external face of the greater trochanter is placed in evidence, upwards and towards the anterior part of the gluteus medius muscle, towards the back are the pelvic trochanterian muscles and below the vastus lateralis.

The decision to section the greater trochanter is defendable if it is esteemed that the exposition of the articulation is perfect, that the section of a bony segment – that will consolidate ad intégrum in 45 days – is preferred over a tendinous section that will never scar over perfectly.

After having liberated the large insertion of the vastus lateralis, the sectioning of the greater trochanter is done with a 25mm bone chisel. During this operation one always tries to respect the insertion of all the pelvic trochanterian muscles with the exception of the crural square which rests attached to the femur.

The greater trochanter is lifted up with a strong clamp. The adhesions between the capsule and gluteus medius are freed. The greater trochanter is then pent-up backward and maintained by several large caliber pins planted in the iliac bone above the acetabulum. (figure 9)

The capsule can then be totally cut out. The dislocation of the femoral head is made towards the front. the leg of the patient passes in front of the other leg and hangs vertically, the plantar vault directed towards the floor. The femoral neck is cut with a oscillating saw according to the preoperative planning based on the clinic observations and the tracings representing the prosthesis.

The preparation of the acetabulum is particularly simple because the exposition is extraordinary. For certain it is the privileged approach in case of complex acetabular problems.

At the end of the intervention, once the prosthesis is in place and the hip reduced, the greater trochanter is reinserted as solidly as possible with the aid of three or four steel threads. One can perhaps modify the initial position of the greater trochanter when there is a major malformation of the architecture of the superior extremity of the femur or an important cotyloid dysplasia that can be corrected.

This trochanterotomy, which during the intervention offers a incomparable situation concerning the joint, is also the origin of longest postoperative follow-up as complete support is not allowed until after six weeks. Despite this moratorium, the risk of pseudarthrosis is common and the revision surgery of this complication is not simple. It is this risk that is the origin of the stormy reputation of this approach.

Trochanterotomy has evolved. Certain surgeons try to preserve a continuity between vastus lateralis and the gluteus medius fiber in order to diminish the risks of postoperative ascension of the trochanter. Others section only anterior half of the greater trochanter, a little in the manner of the Hardinge approach. The procedures of reinserting the greater trochanter varies in such a manner that simply looking at the X-ray permits one to know who was the operating surgeon. The prevention of subsequent dislocations is indispensable especially if the surgeon has put in place a prosthesis with a 22.2mm head.

THE POSTERO-EXTERNAL APPROACH

From the technical point of view, its realisation is simpler. The entire first part of the approach is identical to the external approach of a trochanterotomy. The difference being that the pelvic trochanterian muscles and not the greater trochanter are sectioned.

In certain cases, it is possible to preserve the pyramidal muscle. But the internal obturator and the two Gemellus are obligatorily sacrificed. The hip is progressively placed in internal rotation. The capsule is cut and cut out. The dislocation is made towards the back. And if the inferior limb passes in front of the non operated limb, the leg and the plantar vault faces the ceiling. It is the inverse of what happens in the case of a trochanterotomy.

In general, two or three large caliber pins are planted in the pelvis in order to expose it. The access to the acetabulum and femur is good. It might be necessary to section all the posterior part of the tendon of the gluteus medius if the exposition is not perfect. The reinsertion of the pelvic trochanterian muscles at the end of the intervention is imaginary especially if, as often the case, there existed a limitation of the inside rotation in preoperative.

If this approach has for its merit simplicity, it also generates the most post operative dislocations. The precautions are known but not always sufficient : abduction cushion, raising up the chair and limiting inside rotation when in a sitting position. The use of crutches is vital during the first postoperative month.

AIn terms of this non-exhaustive review of surgical approaches to the hip, one will come to understand that a universal approach does not exist. The pure anterior approach is technically delicate and does not always offer the best solution for the femur; well realised it offers the best postoperative follow-up.

The Hardinge approach can result in postoperative pain and a weakness of the buttocks. The trochanterotomy exposes a risk of pseudarthrosis and the posterior approach leads to postoperative dislocation.