Flexible Reamers – and Anatomic Tunnel Placement Orthopedic Summit 2017 Mark E. Steiner, MD New England Baptist Hospital Boston
Disclosures • Royalties Stryker • Fellowship Support Don Joy Mitek Smith & Nephew Con Med • Research Support Don Joy Stryker
Transtibial Drilling Can Place Nonanatomic Vertical Grafts Independent Drilling Outperforms Conventional Transtibial Drilling in ACL Reconstruction AJSM ‘09 NO YES • • • Anatomic Independent Drilling Transtibial Drilling Anterior Translation + Pivot Normal Translation No Pivot
Can Transtibial Drilling Place an Anatomic Tibial & Femoral Tunnels ? Yes, But . . . AJSM ‘08 Compromise ? Femur AM Tibia PL Impractical Starting point
Transtibial Drilling to place Anatomic Femoral Tunnel Tibial or Femoral Tunnel will be compromised Drilling under Tibial Plateau Failed Vertical Tunnel Conventional Tibial Tunnel Places a Vertical Femoral Tunnel
Failures of ACL Reconstruction • “Failure” up to 25% • Technical error in tunnel Placement (most common reason)
Locating an “Anatomic” Femoral Tunnel • ? Remnants • Clock face • Ridges • Measurements J Arthro 2015
Measurements in 90° flexion Davis J Arthro 2015
FINDING THE ACL WITH MEASUREMENTS KNEE 90° FLEXION Height 7.2 mm 8.7 mm 9.6 mm Depth 33% 55% 66%
Preferred Approach AM Drilling Anatomic Tunnel But Challenge of Hyperflexion Flexible Instruments Outperform Rigid Instruments to Place Anatomic Anterior Cruciate Ligament Femoral Tunnels Without Hyperflexion J Arthro 2011 90 ° 125 °
AM Aimer at Height of ACL → Point close to ACL center • 7 mm offset aimer • Elevated 8.5 mm
View Pilot Hole from Medial Portal Lateral Portal View Medial Portal View
Aimer Placed Through AM Portal Pin Positioned in Starter Hole
Guidepin Placement • Pin Exits in safe zone on lateral thigh
Advance Flexible Reamer Over Pin
Nitinol Pin and Reamer Create a Straight Tunnel
Tunnel low at 90° = Tunnel posterior at 20° V extended 90°
Lateral Wall Impingement with AM Drilling Udagawa AJSM ‘14 “Tibial tunnel should be medial as possible” medial lateral impingement
Failure with Anatomic ACL ? It’s the Tibial Tunne! Galdi OJSM ‘16 Wagner ARTH ’13 AM 7 midsubstance tears 5.2% AM fail vs 3.2% TT fail with lateral wall hypertrophy
Notch Dimensions vary between patients
? Anatomic Tibial Tunnel or Nonimpinging Tibial Tunnel 15 mm
Medial Tibial Tunnel + Anatomic Femoral Tunnel = No Roof or Lateral Wall Impingement
Anatomic Nonimpinging Graft
Keep It Anatomic Old Thank you
Recommend
More recommend