Purpose: A conventional midline posterior approach is used for most of the described surgical techniques. We describe a technique of percutaneous fixation of the pars interarticularis, augmented where necessary by grafting the defect, which minimises muscle injury.
Method: A 4.5 mm partially threaded dynamic compression screw is placed over a wire inserted percutaneously across the pars interarticularis defect. Compression is achieved across the pars interarticularis defect on placement of the screw. The screw is locked in a compressed state.
Results: The patient is mobilised the same day with a corset for comfort and discharged the following day. Aerobic fitness is maintained for 3 months; then, focused rehabilitation performed until a CT scan confirms healing at 5-6 months, at which stage full (sports) activity is resumed.
Conclusions: The minimal tissue injury and small incision used allow for the minimising of complications and for a rapid recovery and discharge from hospital. With adolescents, we have the opportunity to treat symptomatic pars interarticularis defects with minimal disruption to their academic and physical development.
Keywords: Minimally invasive; Percutaneous screw; Spondylolysis.