Medial Malleolar Fixation: Sex Appeal Long 3.5 mm screws Bob Zura, - PowerPoint PPT Presentation

Medial Malleolar Fixation: Sex Appeal – Long 3.5 mm screws Bob Zura, MD LSU Health New Orleans OSET 2017 Las Vegas Acknowledge Bill Ricci

Disclosures • Consultant: – Smith-Nephew – Bioventus – Cardinal Health

http://images.fanpop.com/images/image_uploads/Las-Vegas-united-states-of- america-697059_726_491.jpg TRANSVERSE FRACTURE PATTERNS

Transverse Fracture Fixation • Typically 2 screws • Tension Band

http://1g1uem2nc4jy1gzhn943ro0gz50.wpengine.netdna- cdn.com/wp-content/uploads/2009/11/vegas_strip.jpg NOT VERTICAL FRACTURE PATTERNS

Vertical Fracture • Anti-glide plate • Lag screws

Transverse Fracture Fixation • Typically 2 screws • Tension Band

Transverse Fracture Fixation • Typically 2 screws • Tension Band

What is Best Length?

Or – The New Gold Standard

Objectives Compare medial malleolar screw fixation methods Biomechanical Evaluation Radiographic & Clinical Evaluation

Biomechanics Matched pair human cadavers MM Osteotomy 3.5 mm FT Cortical 4.0 mm PT Cancellous 45 mm 70 mm – 100 mm

Biomechanics • Screws inserted until stripped – Maximum insertion torque measured

Biomechanics - Results 4.0 PT 3.5 FT 20.00 3.9 in-lpf 14.4 in-lpf >3.5 x increase 15.00 P<0.0002 in-lbf 10.00 5.00 0.00 1 2 3 4 5 6

Cohorts N=25 N=64 Age Gender DM Isolated Medial Malleolus Fx’s Bimalleolar Fx’s Syndesmotic Injuries

Results N=25 N=64 Radiographic Loosening 1 (4%) 12 (19%) 1 ROH

Results N=25 N=64 Non-Union 0 2

Study Conclusions • Bicortical lag screws – Preferred method • Technically easy • Requires long screws – Average 80 mm

Thank You!