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.
Patients who have had hip replacements are often told not to lift their knee above the level of their hip, or cross their legs, and with good reason - this is a position of weakness. A combination of hip flexion, adduction and internal rotation places the ball at the posterior rim of the socket, and can allow the ball to roll over the rim. Subsequent decrease of the flexion/adduction/internal rotation leaves the ball sitting behind the rim, with any spasm from the muscles traversing longitudinally over the hip joint causing superior movement of the ball and further wedging of the ball. This can be seen in the X-ray above, and clinically as leg shortening and internal rotation.
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 standing/kneeling over patient. A second operator can be used to help secure the pelvis in place, especially with a light patient, or 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)
If excessive traction is used (or the ‘pull’ operator loses track of the 3-dimensional space due to exertion or positional difficulty) and the following problems can occur which will stop you getting into the correct position and subsequently require huge forces to achieve reduction:
- Pelvis tips upward, this causes a reduction in hip flexion angle, leaving the ball wedged more posteriorly behind the rim. A similar effect can occur with traction directed through the femur in a downwards way during traction.
Abduction of hip either from pelvis being tilted medially (affected side) or the knee being pulled outwards during traction, or a combination of both. This leaves the ball wedged more medially behind the rim.
Flexion to at least 90 degrees
Internal/external rotation to find angle where ball sits on rim of socket
Then apply upwards traction
Click below for a brief tutorial on the flexion technique (with thanks to Dr Nick Bailey).
This is the technique I have used when putting hips back in without sedation/analgesia and so requires a cooperative patient. 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. This technique can also be applied with a sedated patient. Theoretically, this would work with traction applied to a slightly bent knee - a bit awkward to apply but would shorten the hamstrings therefore loosening them further.
Traction – hold ankle with leg in full extension. Lean back to provide gentle steady traction
Lift affected leg over other leg. Aim for hip ‘zero position’ – 30 degrees adduction, 30 degrees flexion
Small internal/external rotation movements
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!”
I’m often asked who my role models are, and the answer is easy – my Dad. These techniques are dedicated to him. Having finally talked Dad into having his hip replaced a couple of years ago, he’s had a new lease of life and runs around coaching football for his grandchildren (he still has a wicked right foot shot!) In fact, the op was so successful he now thinks it was his idea. He’s not a huge fan of hospitals so if at some point in the future you have a grumpy patient called Neil Cunningham who has popped his hip out while attempting an overhead kick, go easy on him, and please make my mum a cup of coffee.