Reduced fluoroscopic radiation, reduced time, increased accuracy Clinical summary of intramedullary nails: Evaluation of a new computer-assisted guidance system *, Panagiotis, Evangelopoulos Dimitrios-Stergios, Vlamis John of Hospital, Athens, Greece goldstandardfor However, distal afrustratingpart of thesurgeon, the a considerable amount of procedure.Insome approacheshalf Fluoroscopy is of great facilitates the the nail’s entry radiationexposure, oftheprocedure methods for IMNs.Theseincludemodifiedfreehandtechniqueswithorwithoutuseof radiolucentdrillsandjigs,mechanical guidingsystemsthatare attachedeithertotheproximal partof thenailortotheimage intensifieror even to the surgical tableand computer- assisted navigation systems with or without application of robotics.Accuratetargetingof thedistal holesisproblematic duetotheinevitabledeformationof thenail after its insertionto thetibiaorthefemurandthatisthemaincauseof failurefor manyoftheaforementionedtargetingsystems, especiallyforthose that are mountedtothe proximal sectionof the nail. Computer- assistedmethodsprovidesatisfactoryaccuracy, butimposestime- consuming set upandstill dependonfluoroscopyfor the initial mapping of the surgical field.Application of electromagnetic fields offers anattractivesolution. The SURESHOTDistal Targeting System(Smith&Nephew, Inc., Memphis, TN, USA) is a novel commercially available radiation-freeaimingsystemutilizingcomputerizedelectromag- netic field tracking technology for distal IMN locking. In a comparativestudywithstandardfluoroscopicfreehandtechnique oncadaveric limbs, the newtechnique was foundto be equally effective(100%vs. 94%for thetibial nail, 96%for bothtechniques forthefemoral nail), faster(by32%forthefemoral nail and47.5% for thetibial nail) totraditional distal locking, whiletheaverage radiation time saved was 36 13sec (tibial nail) and 49 25sec (femoralnail)accountingfor785 285mRadand2362 1232mRad radiationexposuretothelimb, respectively.To evaluate the efficacy of the systemwe conducted the present study. Injury, Int. J. CareInjuredxxx(2012) xxx–xxx * Correspondingauthorat:ThirdOrthopaedicDepartment, UniversityofAthens, KATHospital, 10, Athinasstr., Kifissia, AthensPC14561, Greece. Tel.: +302108018123; fax: +302108018122. E-mail address: [email protected](I. Stathopoulos). ARTI CL E I NF O ABS TRACT lockingofintramedullarynails(IMNs)isadifficultpartofintramedullarynailing(IMN)thatcould time-consumingandexposethesurgeon, thesurgerypersonnel andthepatient toaconsiderable ofradiationasfluoroscopyisusuallyguidingtheprocedure. Utilizationofelectromagneticfields purpose offers anattractive alternative. The SURESHOTDistal Targeting System(Smith& Nephew, Inc., Memphis, TN, USA) is anovel commerciallyavailableradiation-freeaimingsystemthat computerizedelectromagneticfieldtrackingtechnologyforthedistallockingofIMNs. Inorderto evaluatetheefficacyof thesystemweconductedthepresent study. Nineteenpatients (sixfemales– males, meanage39.5years, range17–85years) withcloseddiaphyseal fractureof thefemur patients) or the tibia (elevenpatients) were treated with IMNusing the SURESHOTDistal Targeting Systemfor the distal interlocking. All targeting attempts were successful at first try and followedbycorrect positioningof thescrews. Meantimefor distal lockingof tibial IMNs(twoscrews) 219sec(range200–250sec). Meantimefor distal lockingof femoral IMNs(twoscrews) was249 220–330sec). In the current study the SURESHOTDistal Targeting Systemproved to be accurate, fast andeasytolearn. ß2012Elsevier Ltd. All rightsreserved. G4 Please cite this article inpress as: Stathopoulos I, et al. Radiation-free distal locking of intramedullary nails: Evaluationof a new electromagnetic computer-assistedguidancesystem. Injury(2012), http://dx.doi.org/10.1016/j.injury.2012.08.051 Contentslistsavailableat SciVerseScienceDirect Injury nmepage: www.elsevier.com/locate/injury 0020–1383/$–seefront matterß2012ElsevierLtd. All rightsreserved. http://dx.doi.org/10.1016/j.injury.2012.08.051 ORIGINAL ARTICLE The Insertion of Intramedullary Nail Locking Screws Without Fluoroscopy: A Faster and Safer Technique Daniel S. Chan, MD,* Richard B. Burris, MD,† Murat Erdogan, MD,‡ and H. Claude Sagi, MD* This study was designed to compare the accuracy, time, and radiation exposure during the insertion of intramedullary nail fluoroscopic assistance or an electromagnetic (EM)-based navigational system without fluoroscopy. Patients were divided into 2 groups: group 1 (fluoro- scopic assistance), consisted of standard freehand fluoroscopically assisted insertion of locking screws (OEC 9900; G.E. HealthCare, Waukesha, WI), whereas group 2 (EM), consisted of EM naviga- fluoroscopy (SureShot; Smith & Nephew, Memphis, TN). Technician arrival time, setup (SU) time, fluoroscopy time (seconds), radi- ation exposure (mrads), and accuracy (hit or miss) were recorded for each screw. For group 1, the SU time was recorded as the time and “”before insertion, and for group 2, the SU time was recorded as the time required to set up the navigational EM unit. Data collected regarding SI were then com- Forty-one locking screws were inserted in group 1, whereas 60 screws were inserted in group 2. Accuracy was 100% for both groups. For group 1, mean technician wait time was 77 seconds plus a mean perfect circle SU time of 105 seconds (9.2 mrads and 10 seconds fluoroscopy). Mean SU time for group 2 was 94 seconds (no fluoroscopy). Mean insertion time was 342 seconds per screw for group 1 fluoroscopy) compared with fluoroscopy). These differences fiPThe use of EM navigation (SureShot; Smith & Nephew) for the insertion of intramedullary nail locking screws fluoroscopic-guided insertion. However, EM-guided locking SI resulted in a significantly shorter total procedural time and completely eliminated radiation exposure. Key Words: IMN, fluoroscopy, radiation, locking screw, electro- magnetic, SureShot Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence. (J Orthop Trauma 2013;27:363–366) INTRODUCTION Currently, locking screws for intramedullary nails (IMN) are placed either with a jig attached to the nail or with fluoroscopic assistance (FA) using the “perfect circle” technique. Whether the surgeon is a novice or an expert with this technique, the patient, operating surgeon, and operating room personnel are exposed to additional radiation. Previous studies have reported that the use of fluoroscopy for all lock- ing screw placement can add an additional 1.1–6.9 minutes of fluoroscopy time and an additional 12 mrems of radiation to the dominant hand of the surgeon.1–5 Various techniques have been developed in an effort to decrease or eliminate the need for fluoroscopy during locking screw placement6–11; however, none of these methods have consistently demonstrated sufficient efficacy or accuracy. Recently, a navigational system using electromagnetic (EM) field–based tracking technology (Trigen Sureshot; Smith and Nephew, Memphis, TN) has been developed to assist in the placement of locking screws in IMNs with out the need for fluoroscopy. Tornetta et al reported on a decrease in screw insertion (SI) time while maintaining accuracy without the need for fluoroscopy when this system was tested in a cadav- eric model against the standard freehand technique.12 The purpose of this study was to compare setup (SU) time, fluoroscopic time, radiation exposure, insertion time, and accuracy for intramedullary rod locking screw placement in vivo when using standardfluoroscopically assisted technique and EM navigation without fluoroscopy. Our hypothesis was that the EM technique would require less time and eliminate radiation while maintaining similar or improved accuracy. METHODS Study Design This was a prospective Institutional Review Board approved study. Patients that underwent femoral or tibial From the *Orthopaedic Trauma Service, Florida Orthopaedic Institute, Tampa, †‡Ondokuz Mayis Uni- Presented at the Annual Meeting of the Orthopaedic Trauma Association, H. Claude Sagi is a consultant for Smith & Nephew, Synthes, and Stryker. flThere was no external funding source for this study. The SureShot device was provided for use at our institution by Smith & Nephew, Memphis, TN. Reprints: Daniel S. Chan, MD, Orthopaedic Trauma Service, Florida Ortho- paedic Institute, 5 Tampa General Circle, Suite 710, Tampa, FL 33606 Volume 27, Number 7, July 2013 www.jorthotrauma.com| 363 Next generation distal locking for intramedullary nails using an electromagnetic X-ray-radiation-free real-time navigation system Michael Hoffmann, MD, MBA, Malte Schro ¨der, MD, Wolfgang Lehmann, MD, PhD, Michael Kammal, MD, Johannes Maria Rueger, MD, PhD, and Andreas Herrman Ruecker, MD, Hamburg, Germany Distal locking marks one challenging step during intramedullary nailing that can lead to an increased irradiation and pro- longed operation times. The aim of this study was to evaluate the reliability and efficacy of an X-ray-radiation-free real-time navigation system for distal locking procedures. A prospective randomized cadaver study with 50 standard free-hand fluoroscopic-guided and 50 electromagnetic-guided distal locking procedures was performed. All procedures were timed using a stopwatch. Intraoperative fluoroscopy exposure time and absorbed radiation dose (mGy) readings were documented. All tibial nails were locked with two mediolateral and one anteroposterior screw. Successful distal locking was accomplished once correct placement of all three screws was confirmed. Successful distal locking was achieved in 98 cases. No complications were encountered using the electromagnetic navigation system. Eight complications arose during free-hand fluoroscopic distal locking. Undetected secondary drill slippage on the ipsilateral cortex accounted for most problems followed by undetected intradrilling misdirection causing a fissural fracture of the contralateral cortex while screw insertion in one case. Compared with the free-hand fluoroscopic technique, electro- magnetically navigated distal locking provides a median time benefit of 244 seconds without using ionizing radiation. Compared with the standard free-hand fluoroscopic technique, the electromagnetic guidance system used in this study showed high reliability and was associated with less complications, took significantly less time, and used no radiation exposure for distal locking procedures. (J Trauma Acute Care Surg. 2012;73: 243Y248. Copyright *2012 by Lippincott Williams & Therapeutic study, level II. Intramedullary nailing; distal locking; radiation exposure; targeting devices; time. losed intramedullary nailing has proven its efficacy in the treatment of diaphyseal fractures of long bones.1,2Despite the advances made over the years in nail design and instrumen- tation, distal locking remains a demanding step of the pro- cedure resulting in potential vast theater time consumption3,4 and increased radiation exposure for both the patient and the Great efforts have been made over the years to find an enduring solution for this problem. These include hand-held targeting devices and radiolucent drill guides,7 laser-guided 8 9 self-locking nailing sys- 3 image-intensifier-mounted targeting devices,10,11 and 12 Each of these devices features its own privileges pitfalls, and limitations, and successful use requires a certain learning curve.3 However, proximally mounted targeting devices seem to fail due to lack- ing compensation for insertionrelated deformation of the im- plant.3,12Therefore, the freehand fluoroscopic technique remains the most common method for distal locking.12The purpose of this study was to compare the efficacy of the standard free-hand fluoroscopic technique with a new electromagnetic navigation system for distal locking in terms of reliability, operation time, and radiation exposure. MATERIALS AND METHODS Tibial intramedullary nailing was performed in a pro- spective study on 20 nonfractured cadaveric limbs (10 bodies) using the semi-extended approach with the torso supine. Distal locking was performed randomized using either the standard fluoroscopic free-hand technique or the new electromagnetic navigation system. Both techniques were performed randomized by two senior surgeons locking with one technique and then backing the nail up and rotating it slightly for further locking procedures. For the standard free-hand fluoroscopic technique, the image intensifier was aligned with the two distal nail holes until the passage for each screw appeared as a perfect circle in the center of the image, indicating coaxial alignment of the hole. A following skin incision was made through the fascia, down to the bone cortex. The drill was mounted on a radiolucent drill guide. Targeting was performed using pulsed fluoroscopy aiming for a circle in circle alignment of both the drill guide and the distal locking hole of the nail. Once the hole was palpated ORIGINAL ARTICLE J Trauma Acute Care Surg Volume 73, Number 1 243 Submitted: June 30, 2011, Revised: January 9, 2012, Accepted: January 12, 2012, From the Department of Trauma (M.H., M.S., W.L., J.M.R., A.H.R.), University Medical Centre Hamburg-Eppendorf, Hand and Reconstructive Surgery, Mar- tinistrasse, Hamburg, Germany; and Department of Forensic Medicine (M.K.), University Medical Centre Hamburg-Eppendorf, Martinistrasse, Hamburg, Germany. Address for reprints: Michael Hoffmann, MD, MBA, Department of Trauma, Uni- versity Medical Centre Hamburg-Eppendorf, Hand and Reconstructive Surgery, Martinistrasse 52, D-20246 Hamburg, Germany; email: [email protected]. DOI: 10.1097/TA.0b013e31824b0088 Copyright © 2012 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. ORIGINAL ARTICLE Distal Locking Using an Electromagnetic Field–Guided Computer-Based Real-Time System for Orthopaedic Trauma Patients Maxwell K. Langfitt, MD,* Jason J. Halvorson, MD,* Aaron T. Scott, MD,* Beth P. Smith, PhD,* Gregory B. Russell, MS,† Riyaz H. Jinnah, MD, FRCS,* Anna N. Miller, MD,* and Eben A. Carroll, MD* Objectives: To compare the efficacy of distal interlocking during intramedullary nailing using a freehand technique versus an electromagnetic field real-time system (EFRTS). Design: A prospective, randomized controlled trial. Setting: Level I academic trauma center. Patients/Participants: Patients older than 18 years who sus- tained a femoral or tibial shaft fracture amenable to antegrade intramedullary nailing were prospectively enrolled between August 2010 and November 2011. Exclusion criteria included injuries requiring retrograde nailing and open wounds near the location of the distal interlocks (distal third of the femur, knee, or distal tibia). Intervention: Each patient had 2 distal interlocking screws placed: one using the freehand method and the other using EFRTS. Main Outcome Measurement: Techniques were compared on procedural time and number of interlocking screw misses. Two time points were measured: time 1 (time tofind perfect circles/time from wand placement to drill initiation) and time 2 (drill initiation until completion of interlocking placement). Results: Twenty-four tibia and 24 femur fractures were studied. EFRTS proved faster at times 1 and 2 (P,0.0001 andP,0.0002) and total time (P ,0.0001). This difference was larger for junior residents, though reached statistical significance for senior residents. Senior residents were faster with the freehand technique compared with junior residents (P ,0.004), but the 2 were similar using EFRTS (P= 0.41). The number of misses was higher with free hand compared with EFRTS (P= 0.02). Conclusion: These results suggest that EFRTS is faster than the traditional freehand technique and results in fewer screw misses. Key Words: distal locking, intramedullary nailing, femur/tibia frac- ture, electromagnetic, fluoroscopy, orthopaedic trauma Level of Evidence: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence. (J Orthop Trauma 2013;27:367–372) INTRODUCTION Intramedullary nails are the gold standard for the treatment of lower extremity long bone fractures.1–4The tech- nique for both femoral and tibial antegrade nails has been well described.1–3Many surgeons use a freehand or "perfect circle" technique for placement of the distal locking screws, which involves intraoperative fluoroscopy to guide freehand drilling through the bone and intramedullary nail followed by place- ment of the locking screw. Although effective, potential pit- falls of this technique include increased operative time and radiation exposure, as well as the potential to "miss" the nail with the drill or locking screw. For surgeons who do not often perform intramedullary nailing, distal locking can be difficult and time consuming. To improve the method of distal locking screw placement, an ideal system would decrease radiation exposure, improve accuracy of drill/screw placement, be easy and accessible to the community surgeon, and decrease oper- ating room time while also being cost effective. Numerous systems and techniques have been proposed and are well described.5–15 However, many of these systems continue to expose the patient and surgeon to radiation, are cumbersome, and may have a steep learning curve for the surgeon. A new system, an electromagnetic field real-time system (EFRTS) (Trigen Sureshot, Smith & Nephew, Mem- phis, TN), aims to provide surgeons with a fast, reliable, and accurate technique for distal locking screw placement without radiation exposure. The EFRTS uses an electromagnetic field Accepted for publication February 7, 2013. From the *Department of Orthopaedic Surgery, Wake Forest Baptist Medical Center, Winston-Salem, NC; and †Department of Biostatistical Sciences, Wake Forest Baptist Medical Center, Winston-Salem, NC. This study was supported by research grant provided by Smith and Nephew. Dr. Anna Miller receives research support from Synthes and Smith and Nephew not related to this study. Drs M. K. Langfitt, J. J. Halvorson, B. P. Smith, E. A. Carroll, and Mr G. B. Russell have nothing to disclose that relates to this study and no conflicts of interest that relate to this study. Dr A. T. Scott has provided expert testimony and given lectures in an activity unrelated to this study. Presented as a podium presentation at the Eastern Orthopaedic Association Conference, Bolton Landing, NY, June 21, 2012, and at the Southern Orthopaedic Association Conference, White Sulphur Springs, WV, July 19 2012. Reprints: Eben A. Carroll, MD, Department of Orthopaedic Surgery, Wake Forest Baptist Medical Center, Medical Center Boulevard, Winston- Salem, NC 27157 (e-mail: [email protected]). Copyright © 2013 by Lippincott Williams & Wilkins J Orthop Trauma Volume 27, Number 7, July 2013 www.jorthotrauma.com| 367