The surgical hip dislocation approach is a combination of the posterior-lateral approach with a trochanteric flip and anterior dislocation of the hip. The advantage of this technique is access to the entire hip joint without compromising the blood supply to the femoral head.

Slipped-capital femoral epiphysis (SCFE)

SCFE is a condition that affects the femoral head at the level of the growth plate where the femoral head slips off the neck. In lay terms, can be described as the ice cream falling off the ice-cream cone. This most often happens in overweight adolescents between the ages of 10-16. Treatment varies depending on the type of slip and severity.

Classic treatment is called pinning in situ (see procedure pinning in situ), where the femoral head is kept from further slipping off the neck by 1 or 2 large screws that eventually cause the growth plate to close (refer to pictures 1-3 below). This treatment does not correct the underlying slip deformity, which can lead to femoral-acetabular impingement causing labral tears and pre-mature wearing of the hip.

Picture 1                                                                                  Picture 2

Picture 3

Surgical hip dislocation as a treatment for SCFE (refer to picture 4), corrects the slip deformity by putting the femoral head back on the neck (the ice cream back onto the cone) safely and holding it there with 2 large screws (refer to picture 5). By correcting the deformity of the slip, the hip can then function normally without impinging.

Picture 4: Surgical hip x-ray with a SCFE

 

Picture 5

Femoral-acetabular impingement

Femoral-acetabular impingement is a condition affecting young adults where the shape of the femoral neck or acetabulum (the ball or the socket) are abutting (impinging) one another causing pain and damage to the hip joint.

There are two types (or a combination of both):

  • CAM impingement:is when there is a bump lesion on the femoral neck that impinges on the acetabulum (the socket)
  • Pincer impingement:is when the acetabulum (the socket) is protruding out and impinging on the femoral neck.

Illustration demonstrating cam (A) and pincer (B) femoroacetabular impingement. (Reproduced with permission from Ganz R, Parvizi J, Beck M, Leunig M, Nötzli H, Siebenrock KA: Femoroacetabular impingement: A cause for osteoarthritis of the hip. Clin Orthop Relat Res 2003;417:112-120.)

Surgical intervention to reshape the femoral neck or the acetabulum or both is sometimes required to prevent further damage and alleviate the symptoms.  Hip arthroscopy (see procedure Hip arthroscopy) is the preferred surgical option for CAM type impingement. For pincer impingement, a surgical hip dislocation is often necessary to adequately correct the problem

Surgical technique:

  1. The patient is placed on the table in a lateral position (on the side).
  2. A lateral skin incision is made.
  3. The leg is internally rotated so we can see the posterior border of the gluteus medius muscle. This muscle is traced to the posterior ridge of the vastus lateralis muscle.
  4. A 1.5cm thick trochanteric osteotomy is performed following the trace mentioned above using a saw.
  5. The soft tissues are pulled aside and an incision is made of the anterolateral surface of the hip capsule.
  6. The hip is then dislocated anteriorly by flexing and externally rotating the femur.
  7. The leg is then placed in a sterile bag over the front of the table
  8. The surgeon can now access the femoral head and the acetabulum and address the pathology as needed.
  9. A 2.0mm hole is drilled in the femoral head to document preservation of the blood supply and assess viability of the head during this portion of the surgery.

For SCFE

  • If unstable, prior to dislocating the hip, 2 K-wires are placed to secure the head to the neck.
  • Once dislocated, the neck periosteum (layer of fascia around the bone) of the femur is cut and peeled (like a banana) on the anterior-lateral portion of the neck to preserve the blood supply to the femoral head (refer to picture 6).
  • The neck is exposed to be able to reposition the head on the neck and two large screws are used to fix it in place (refer to picture 7).

Picture 6

Picture 7

For FAI

  • For pincer impingement, the labrum is detached from the acetabulum like a bucket handle and the overhanging bone of the acetabulum is removed (refer to picture 8).
  • The labrum is then re-attached using anchors
  • The femoral neck is then assessed for CAM lesions and reshaped to ensure that there is no impingement (refer to pictures 9-10).

Picture 8

Picture 9                                                                                                Picture 10

  1. The hip is then reduced by applying manual traction on the flexed knee followed by internal rotation and extension.
  2. The wound is irrigated and the capsulotomy is closed with a vicryl suture.
  3. The greater trochanter is secured using two 3.5mm cortical screws directed towards the lesser trochanter.
  4. The tensor fascia lata and soft tissues, as well as the skin, are then closed.

 

Post-Operative Care

Dressings are left in place until 1st follow up visit 10-14 days after surgery.

The patient is permitted to shower after 1st follow up appointment 10-14 days after surgery.

Prophylactic anticoagulation with subcutaneous injections are generally recommended for at least 2 weeks but will vary depending on the patients underlying conditions.

Heterotopic ossification prophylaxis is given by taking oral anti-inflammatory medication for 6 weeks.

X-rays are done post-operatively in order to ensure adequate alignment and concentric hip reduction.

Physiotherapy after surgery

For SCFE:

Patients are placed in a hip spica brace and are permitted to toe touch weight bear on the affected side for 6 weeks after surgery and then progressively increase their weight bearing. Training is provided to use crutches to assist walking.

For FAI:

Patients are placed in a hip spica brace and are permitted to weight bear as tolerated with crutches.

Mobilisations of the hip joint begin immediately after surgery and strengthening exercises are added gradually with the supervision of a qualified physiotherapist.

Potential complications

  • Avascular necrosis (AVN) of the femoral head
  • Nerve injury to the sciatic nerve (Neuropraxia)
  • Trochanteric non-union or malunion
  • Heterotopic ossification
  • Infection of the bone (osteomyelitis)
  • Neurovascular injury (rare)
  • Deep vein thrombosis (rare)

For a complete list of the risks and complications, please see Patient info.

Patients who will undergo this procedure should read the following sections in the Patient information tab.

1- Immediate post-operative care