Acetabular Screw Placement and Safe Zones Draw quadrants first line drawn from ASIS to center of acetabulum second line drawn perpendicular to first line Quadrant posterior-superior quadrant "target zone" is the ideal place for supplemental component screws. elevating the hip center in revisions can place sciatic nerve at risk in this quadrant posterior-inferior quadrant "caution zone" if screw exceeds 20mm the following structures are at risk sciatic nerve inferior gluteal nerve and vessels internal pudendal nerve and vessels anterior-inferior quadrant "danger zone" obturator nerve, artery, and vein at risk anterior-superior quadrant "death zone" external iliac vessels at risk Exceptions in the "high hip" the structures in the anterosuperior and anteroinferior quadrants are often found in the posterosuperior quadrant Avoiding Prosthesis Impingement Leaving the anterior rim of the acetabular component proud above the native acetabulum may result in anterior iliopsoas tendon impingement evaluate with cross-table lateral radiograph and anesthetic injection of the iliopsoas tendon sheath Causes of impingement medializing and raising acetabulum cup center of rotation will increase risk of bone-on-bone impingement by decreasing femoral offset lateralizing cup will increase risk of metal femoral neck-on-metal acetabulum impingement femoral head-to-neck ratio (<2:1) will increase risk of impingement femoral head skirts small femoral head
QUESTIONS 1 of 6 1 2 3 4 5 6 Previous Next Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (OBQ11.92) A 64-year-old male undergoes acetabular revision of his failed total hip arthroplasty using a large uncemented component. Post-operatively he is noted to have a foot drop and radicular pain in the operative extremity. A CT scan of the hip is obtained and reveals screw penetration into the sciatic notch. Where was this screw most likely inserted in the acetabulum? QID: 3515 Type & Select Correct Answer 1 Anterior superior quadrant 5% (226/4370) 2 Through the medial wall 6% (249/4370) 3 Anterior inferior quadrant 9% (396/4370) 4 Posterior superior quadrant 77% (3377/4370) 5 Through the femoral nerve 2% (101/4370) L 1 Question Complexity B Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 4 Review Tested Concept Review Full Topic (OBQ11.5) In order to determine the boundaries of the posterior-superior safe zone for acetabular screw placement during THA, a line is initially drawn through which of the following two anatomic landmarks, represented by dots on the illustration? QID: 3428 FIGURES: A Type & Select Correct Answer 1 A and C 61% (2918/4776) 2 B and C 8% (365/4776) 3 D and C 16% (763/4776) 4 C and E 3% (123/4776) 5 A and E 12% (586/4776) L 1 Question Complexity B Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 1 Review Tested Concept Review Full Topic Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (OBQ04.160) When placing acetabular screws to supplement cementless acetabular fixation in total hip arthroplasty, placing screws in which zone poses the highest risk to damaging the external iliac vasculature? QID: 1265 Type & Select Correct Answer 1 anterior-inferior zone 15% (545/3646) 2 anterior-superior zone 77% (2814/3646) 3 posterior-inferior zone 4% (160/3646) 4 posterior-superior zone 3% (106/3646) 5 oblique zone 0% (12/3646) L 1 Question Complexity C Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 2 Review Tested Concept Review Full Topic
All Videos (5) Podcasts (1) 2021 ICJR 10th Annual Direct Anterior Approach Hip Course Acetabular Exposure in Direct Anterior Hip Replacement - Ted Manson, MD Recon - THA Acetabular Screw Fixation 7/26/2022 624 views 4.8 (5) Login to View Community Videos Login to View Community Videos 2021 ICJR 10th Annual Direct Anterior Approach Hip Course ICJR '21 The Acetabulum Panel Discussion Recon - THA Acetabular Screw Fixation 7/26/2022 26 views 0.0 (0) Login to View Community Videos Login to View Community Videos Acetabular Component Extraction with a Motorized Saw - Tim P. Lovell, MD Recon - THA Acetabular Screw Fixation 7/26/2022 8 views 0.0 (0) Recon⎪THA Acetabular Screw Fixation Orthobullets Team Recon - THA Acetabular Screw Fixation Listen Now 0:0 min 5/13/2020 211 plays 5.0 (2) See More See Less
INFECTED BIPOLAR HRA RIGHT HIP WITH HETEROTOPIC OSSIFICATION AND FIRST STAGE REVISION THR (C2215) Rohit Vikas Recon - THA Acetabular Screw Fixation E 4/27/2015 58 1 9 knee stiffness (C1822) Mohammed Al Sobeai Recon - THA Acetabular Screw Fixation E 3/13/2014 91 0 4 hip dislocation,hip arthritis ;resorbed humeral head (C1470) Surendra Shetty Recon - THA Acetabular Screw Fixation E 4/8/2013 88 1 6 See More See Less