Hip Dislocation - posterior prosthesis

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These techniques are described for the most common type of hip dislocation, which is the posterior dislocation of the artificial hip. The natural hip is a true ball and socket joint, unlike the shoulder which is more like a golf ball resting on a tee. This gives the hip far more stability but less range of movement, with large forces (high velocity trauma) required to dislocate the joint, meaning that associated injuries almost always occur - simple closed reduction in the emergency department may not be possible.

The following techniques use either the position of weakness (flexion/adduction/internal rotation) or a zero position-style technique to reduce the effect of the spasming muscles to cause reduction. Due to the true ball and socket nature of this artificial joint and the inherent stability (in normal position) and tightness (in dislocation) of the surrounding muscles, an element of traction is usually required. This should not be applied until the desired position is achieved for the flexion position, and only applied in a steady continuous manner throughout movement for the extension technique.

This technique can be done with the operator stood next to the bed (my preference) or squatting on the bed over the patient. This will depend on your size and length of levers (forearms etc) and the size/weight of the patient's leg. A second operator can be used to help secure the pelvis in place, they are more likely to slide with any traction if they are light weight or on a moving surface (such as a slide sheet). This operator is not trying to fight against your traction, which should only be applied once in the correct position - at least 90 degrees flexion, adduction, and internal rotation, and with a 'feel 'of the head at the rim of the socket.  

Click here for a clinical video demonstrating this technique (with thanks to Nick FareBrother, Dr Rachel O'Dwyer and Dr Domagoj Vodanovich)

1 - Flexion to at least 90 degrees

2 - Adduct to approximately 30 degrees

3 - Find the spot. Internal/external rotation to find angle where ball sits on rim of socket (you may feel a clunking movement)

4 - Traction. Fix the pelvis, then (and only then)  apply upwards traction ensuring you maintain flex/adduct positioning as you pull up through the axis of the femur

5 - Rotation while maintaining traction. Add internal/external rotation movements - the knee shouldn't move side to side or anterior/posterior, just rotate. The femoral axis shouldn't change, the rotation at the knee transmitted through to femoral head.

Click below for a brief tutorial on the flexion technique (with thanks to Dr Nick Bailey).

1 - Comfortable squat that does not extend the hip when you 'sit back' into it

2 - Elbows wedged into thighs for a leverage from a stable platform

3 - Hands under patient's knee

4 - Patient's foot firmly in your abdomen

Click below for a step-by-step demonstration of the on-the-bed flexion technique including the starting position.

This is the technique I have used when putting hips back in without sedation/analgesia and so requires a cooperative patient. Can also be used once you have sedated/relaxed a patient, and can be a good option if the lower limb is very heavy.This technique is aiming for a hip ‘zero position’ where the majority of the muscles traversing the hip are aligned in a longitudinal fashion over the hip. This removes the translational forces of the muscles and with a combination of voluntary relaxation of the muscles and longitudinal traction at the right angle, can result in a gentle reduction. Final position is approximately 30 degrees adduction, 30 degrees flexion. A small amount of internal rotation and momentum generated by small internal/external rotation movements assist with the final point of reduction. Theoretically, this would work with traction applied to a slightly bent knee - a bit awkward to apply (patient diagonal and leg hanging off bed) but would shorten the hamstrings therefore loosening them further.

Click below for a brief video tutorial on the extension technique (with thanks to Dr Nick Bailey)

I live in Melbourne and for the locals, AFL is a massive part of the culture. So, when I went to see a frustrated elderly gentleman who had been brought into resus he was less annoyed by his recurrent hip dislocation than the fact that he was going to miss watching the match with his mate. He had been on a tram when he decided to tie his shoelace, the tram jerked and next minute his hip was out and he was on the floor. Having spent a few days in hospital recently following a dislocation he was very unimpressed at the idea of staying in again. After a quick X-Ray to confirm the diagnosis I suggested trying a drug free technique which would at least reduce the amount of time he would need to stay in hospital. He readily agreed and a quick extension technique later the hip slipped in painlessly. My man didn’t even wait for a repeat X-ray, jumping out of bed and walking out with a “thanks doc, I’ll get to my mate’s house for the match!”