Sacroiliac joint cut accuracy: Comparing new technologies in an idealized sawbones model

The anatomical complexity of the pelvis creates challenges for orthopaedic oncologists to accurately and safely resect tumors involving the sacroiliac joint. Current technology may help overcome these obstacles.

Four fellowship-trained orthopaedic oncologists performed 22 all-posterior sacroiliac cuts using freehand, computerized navigation, and patient-specific cutting guides on a Sawbones male pelvis model. Cut accuracies to preoperative planned margins were analyzed via a high-resolution optical scanner. Soft tissue damage was determined by visually inspecting the Sawbones foam placed on the far side of the cut.

Within 5 mm of the margins, the freehand technique resulted in 67.0% cut accuracy, the navigation technique had 71.1%, and the patient-specific cutting guide technique had 85.6% (P = .093). Within 2 mm, the techniques showed an accuracy of 25.8%, 32.5%, and 47.5%, respectively (P = .022). Regarding soft tissue damage, the freehand technique exhibited minimal penetration damage for 16.7% of the cuts, while navigation and patient-specific guide techniques exhibited 25.0% and 75.0%, respectively (P = .046). Years of surgical experience of the operator (1-7) did not influence the cut accuracy for any method.

Under ideal conditions, patient-specific guide technology possesses the same or better accuracy as other cutting techniques as well as the circumvention of soft tissue damage.