Posterior Approach to Sacroiliac Joint

The posterior approach to sacroiliac joint is a simple, safe approach that does not endanger any vital structures.
Posterior Approach to Sacroiliac Joint uses include:
1. Open reduction and internal fixation of disruptions of the sacroiliac joint.
2. Open reduction and internal fixation of fractures of the ilium near the joint.
3. Treatment of infections of the sacroiliac joint or surrounding bones.
The popularity of this approach has decreased with the increasing use of percutaneous screw fixation techniques.

Landmarks:
1. Posterior iliac crest.
2. Posterior superior iliac spine.
Incision:
- Make a curved incision overlying the posterior iliac crest, beginning 3 cm distal and lateral to the posterior superior iliac spine.
- Extend the incision from this spot to the posterior superior iliac spine and then continue along the crest to its highest point.

Divide the subcutaneous tissues in line with the skin incision.
Cut down into the outer border of the subcutaneous surface of the iliac crest to reveal the layer of fascia that covers the gluteus maximus muscle.
Detach the origin of the gluteus maximus from the crest and carefully reflect the muscle downward and laterally.
As the gluteus maximus muscle is reflected, the gluteus medius and piriformis muscles will be uncovered as they emerge through the greater sciatic notch.

Gently elevate the gluteus medius muscle from the outer wing of the ilium.
The muscle cannot be elevated much anteriorly because its deep surface is tethered by its neurovascular bundle , the superior gluteal nerves and vessels.
In cases of trauma, the ruptured sacroiliac joint or fracture is easily visible, but reduction is extremely difficult.
To evaluate any reduction, detach part of the origin of the piriformis muscle from around the greater sciatic notch and insert a finger through the notch to palpate the joint from its anterior surface.
The surface of the joint will feel smooth if it has been reduced.

The Posterior Approach to Sacroiliac Joint can be extended anteriorly and the gluteus medius and gluteus minimus muscles elevated from the outer side of the iliac wing.
This will enable more extensive fractures of the wing and the ilium to be dealt with.