Surgical Procedure
The tip of the probe palpates the defect and opening in the subtalar joint (see diagnostic image) and locates the opening of the cyst. When you place the 5 mm sheath with trocar parallel to the probe, the drill will exactly end up in the cyst. The probe and sheath with trocar are introduced through the same portal. The scope is in the posterolateral portal while the trocar with sheet is in the posteromedial portal. After removing the trocar, the 4.5 mm drill is applied through the 5 mm sheath.
A 4.5-mm drill is used to create a hole in the posterior talar process. The drill goes right into the cyst.
Situation after drilling a 4.5-mm drill hole into the cyst with the tip of the probe in the cyst. The scope now is in the posteromedial portal while the probe is in the posterolateral portal.
The cyst is filled with a bone graft (red circle).
Pearls & Pitfalls
Pearls & Pitfalls
1. Positioning the probe exactly into the opening of the cyst. This will determine the direction of your drill (exactly parallel to the probe).
2. When applying the bone graft through the sheath, apply small pieces at a time it can be useful to stop irrigation at this point and perform a dry scope procedure.