Observational Prospective Unblinded Case-Control Study to Evaluate the Effect of the Gamma3® Distal Targeting System for Long Nails on Radiation Exposure and Time for Distal Screw Placement

Published:November 21, 2022DOI:


      • The Stryker Gamma3® Distal Targeting System was found to significantly decrease radiation exposure (77% lower) compared to the freehand “perfect circles” method.
      • Use of the distal targeting system resulted in significantly decreased time from lag screw placement to placement of distal interlocking screw (60% lower).
      • Fluoroscopy time was significantly less using the distal targeting system compared to the perfect circles method (64% lower).
      • There were zero misdrillings with the distal targeter and no difference in complications at 30 and 90 days versus the perfect circles method.



      To determine if the DTS decreases radiation exposure (primary outcome measure), fluoroscopy time (secondary outcome measure), and time to distal screw placement (secondary outcome measure) compared to the freehand “perfect circles” method when used for locking of cephalomedullary nails in the treatment of femur fractures


      Fifty-eight patients with hip or femoral shaft fractures that were treated with a long cephalomedullary nail were enrolled in this study. Cohorts were determined based on the method of distal interlocking screw placement into either the “Perfect Circles” or “Distal Targeting” cohort. Time from cephalad screw placement to placement of final distal interlocking screw (seconds), radiation exposure (mGy), and fluoroscopy time (seconds) were compared between groups. Hospital quality measures were compared between cohorts.


      Use of the DTS resulted in 77% (4.3x) lower radiation exposure (p<0.001), 64% (2.7x) lower fluoroscopy time (p<0.001), and 60% (1.7x) lower intraoperative time from end of cephalad screw placement to end of distal interlocking screw placement (p<0.001) compared to the freehand “perfect circles” method. There was no difference in 30-day or 90-day complication rates between cohorts.


      The Stryker Gamma3® Distal Targeting System is a safe, effective and efficient alternative to the freehand “perfect circles” method.


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