Monocentric Study on Acetabulum Patient-specific Pin Drilling Guides

Prospective Randomised Controlled Monocentric Study on Acetabulum Patient-specific Pin Drilling Guides

A prospective, interventional, monocentric, controlled and randomized study will compare a conventional surgical technique to a surgical technique with the assistance of the Acetabular Cup Orientation Guide (ACOG, Materialise) System during total hip replacement (THR).

Background: The Acetabular Cup Orientation Guide(ACOG) System from MATERIALISE NV was developed and is intended to be used as a surgical instrument to assist in the positioning of acetabular cup components intra-operatively using anatomical landmarks of the pelvis that are clearly identifiable on preoperative computed tomography (CT) imaging scans. Use of ACOG is a relative new technique. ACOG, based on CT imaging data, fit directly into the patient's anatomy and enable primary total hip replacement . Data showing extra benefit of this technique compared to conventional THR technique are not widely available. Aim: To determine the safety of this new surgical technique compared to conventional THR. Methods: 30 participants will be randomized to 2 groups. One group will be operated for a THR with the conventional technique and the other group will be operated for a THR with the assistance of the ACOG System. CT imaging will be taken pre and post operatively to measure cup orientation.

Full leg computed tomography pre-operatively and post-operatively. Cup positioning will be recorded in both groups.

Inclusion Criteria: Is selected to undergo a primary THR Informed consent Exclusion Criteria: Is unable to undergo CT imaging of the full pelvis Requires surgical treatment within less than 4 weeks of initiation Is unable to undergo a THR through a anterolateral approach Presents acute/chronic local or systemic infection Is allergic to polyamide Patient's BMI > 35 Patients with severe wear of the acetabular rim or other disorders that affect acetabular rim anatomy and bony landmark recognition.Patients exhibiting severe wear. Has impaired decision-making capacity Is a prisoner Is pregnant Has metal components that will result in scatter on the CT imaging

Hananouchi T, Saito M, Koyama T, Hagio K, Murase T, Sugano N, Yoshikawa H. Tailor-made surgical guide based on rapid prototyping technique for cup insertion in total hip arthroplasty. Int J Med Robot. 2009 Jun;5(2):164-9. doi: 10.1002/rcs.243.

Hananouchi T, Saito M, Koyama T, Sugano N, Yoshikawa H. Tailor-made Surgical Guide Reduces Incidence of Outliers of Cup Placement. Clin Orthop Relat Res. 2010 Apr;468(4):1088-95. doi: 10.1007/s11999-009-0994-4. Epub 2009 Jul 24.