Radiation Risk in Orthopedic Surgery: Ways to Protect Yourself and the Patient

Intraoperative fluoroscopic radiation in orthopedic trauma: correlation with surgery type and surgeon experience

Background

While fluoroscopy is widely used in orthopedic trauma surgeries, it is associated with harmful effects and should, therefore, be minimized. However, reference values for these surgeries have not been defined, and it is not known how surgeon experience affects these factors. The aims of this study were to analyze the radiation emitted and exposure time for common orthopedic trauma surgeries and to assess whether they are affected by surgeon experience.

Methods

Data from 1842 trauma orthopedic procedures were retrospectively analyzed. A total of 1421 procedures were included in the analysis. Radiation dose and time were collected to identify reference values for each surgery and compared for when the lead surgeon was a young resident, a senior resident, or a specialist.

Results

The most performed surgeries requiring fluoroscopy were proximal femur short intramedullary nailing (n = 401), ankle open reduction and internal fixation (ORIF) (n = 141), distal radius ORIF (n = 125), and proximal femur dynamic hip screw (DHS) (n = 114). Surgeries using higher radiation dose were proximal femur long intramedullary nailing (mean dose area [DAP]): 1361.35 mGycm²), proximal femur DHS (1094.81 mGycm²), and proximal femur short intramedullary nailing (891.41 mGycm²). Surgeries requiring longer radiation time were proximal humerus and/or humeral shaft intramedullary nailing (02 mm:20 ss), proximal femur long intramedullary nailing (02 mm:04 ss), and tibial shaft/distal tibia intramedullary nailing (01 mm:49 ss). Senior residents required shorter radiation time when performing short intramedullary nailing of the proximal femur than young residents. Specialists required more radiation dose than residents when performing tibial nailing and tibial plateau ORIF and required longer radiation time than young residents when performing tibial nailing.

Conclusions

This study presents mean values of radiation dose and time for common orthopedic trauma surgeries. Orthopedic surgeon experience influences radiation dose and time values. Contrary to expected, less experience is associated with lower values in some of the cases analyzed.

Improved Radiation Exposure Monitoring of Orthopaedic Residents After Institution of a Personalized Lead Protocol

Background:

Radiation exposure of orthopaedic residents should be accurately monitored to monitor and mitigate risk. The purpose of this study was to determine whether a personalized lead protocol (PLP) with a radiation monitoring officer would improve radiation exposure monitoring of orthopaedic surgery residents.

Materials and Methods:

This was a retrospective case-control study of 15 orthopaedic surgery residents monitored for radiation exposure during a 2-year period (March 2017 until February 2019). During the first 12-month period (phase 1), residents were given monthly radiation dosimeter badges and instructed to attach them daily to the communal lead aprons hanging outside the operating rooms. During the second 12-month period (phase 2), a PLP (PLP group) was instituted in which residents were given lead aprons embroidered with their individual names. A radiation safety officer was appointed who placed the badges monthly on all lead aprons and collected them at the end of the month, whereas faculty ensured residents wore their personalized lead apron. Data collected included fluoroscopy use time and radiation dosimeter readings during all orthopaedic surgeries in the study period.

Results:

There were 1,252 orthopaedic surgeries using fluoroscopy during phase 1 in the control group and 1,269 during phase 2 in the PLP group. The total monthly fluoroscopy exposure time for all cases averaged 190 minutes during phase 1 and 169 minutes during phase 2, with no significant difference between the groups (p < 0.45). During phase 1, 73.1% of the dosimeters reported radiation exposure, whereas during phase 2, 88.7% of the dosimeters reported radiation exposure (p < 0.001). During phase 1, the average monthly resident dosimeter exposure reading was 7.26 millirems (mrem) ± 37.07, vs. 19.00 mrem ± 51.16 during phase 2, which was significantly higher (p < 0.036).

Conclusions:

Institution of a PLP increased the compliance and exposure readings of radiation dosimeter badges for orthopaedic surgery residents, whereas the actual monthly fluoroscopy time did not change. Teaching hospitals should consider implementing a PLP to more accurately monitor exposure.

Level of Evidence:

3.

Ionization Radiation Shielding Effectiveness of Lead Acetate, Lead Nitrate, and Bismuth Nitrate-Doped Zinc Oxide Nanorods Thin Films: A Comparative Evaluation

The fabrication of Nano-based shielding materials is an advancing research area in material sciences and nanotechnology. Although bulky lead-based products remain the primary choice for radiation protection, environmental disadvantages and high toxicity limit their potentials, necessitating less costly, compatible, eco-friendly, and light-weight alternatives. The theme of the presented investigation is to compare the ionization radiation shielding potentialities of the lead acetate (LA), lead nitrate (LN), and bismuth nitrate (BN)-doped zinc oxide nanorods-based thin films (ZONRs-TFs) produced via the chemical bath deposition (CBD) technique. The impact of the selected materials' doping content on morphological and structural properties of ZONRs-TF was investigated. The X-ray diffractometer (XRD) analyses of both undoped and doped TFs revealed the existence of hexagonal quartzite crystal structures. The composition analysis by energy dispersive (EDX) detected the corrected elemental compositions of the deposited films. Field emission scanning electronic microscope (FESEM) images of the TFs showed highly porous and irregular surface morphologies of the randomly aligned NRs with cracks and voids. The undoped and 2 wt.% BN-doped TFs showed the smallest and largest grain size of 10.44 nm and 38.98 nm, respectively. The linear attenuation coefficient (µ) values of all the optimally doped ZONRs-TFs measured against the X-ray photon irradiation disclosed their excrement shielding potency. The measured µ values of the ZONRs-TFs displayed the trend of 1 wt.% LA-doped TF > 1 wt.% LN-doped TF > 3 wt.% BN-doped TF > undoped TFs). The values of μ of the ZONRs-TFs can be customized by adjusting the doping contents, which in turn controls the thickness and morphology of the TFs. In short, the proposed new types of the LA-, LN- and BN-doped ZONRs-TFs may contribute towards the development of the prospective ionization radiation shielding materials.

Malaysian Nurses' Knowledge of Radiation Protection: A Cross-Sectional Study

Radiology is a vital diagnostic tool for multiple disorders that plays an essential role in the healthcare sector. Nurses are majorly involved in a healthcare setting by accompanying patients during the examination. Thus, nurses tend to be exposed during inward X-ray examination, requiring them to keep up with radiation use safety. However, nurses' competence in radiation is still a concept that has not been well studied in Malaysia. The study aimed to define the level of usage understanding and radiation protection among Malaysian nurses. In this research, a cross-sectional survey was conducted among 395 nurses working in hospitals, clinics, and other healthcare sectors in Malaysia. The survey is based on the developed Healthcare Professional Knowledge of Radiation Protection (HPKRP) scale, distributed via the online Google Forms. SPSS version 25.0 (IBM Corporation) was used to analyze the data in this study. Malaysian nurses reported the highest knowledge level in radiation protection with a mean of 6.03 ± 2.59. The second highest is safe ionizing radiation guidelines with 5.83 ± 2.77, but low knowledge levels in radiation physics and radiation usage principle (4.69 ± 2.49). Therefore, healthcare facilities should strengthen the training standards for all nurses working with or exposed to radiation.

Does Computer-assisted Surgery Improve Lag Screw Placement During Cephalomedullary Nailing of Intertrochanteric Hip Fractures?

BACKGROUND

Computer-assisted surgery (CAS) techniques have been shown to improve implant placement and reduce the radiation time during cephalomedullary nailing in cadaveric and pilot clinical studies of intertrochanteric hip fractures. However, clinical comparisons of CAS and conventional techniques are lacking. It is unclear whether CAS offers clear advantages in terms of radiation time, operative time, and accuracy of lag-screw placement in patients undergoing surgery for intertrochanteric hip fractures and whether any potential difference in accuracy is associated with a change in the risk of lag-screw cut-out postoperatively.

QUESTIONS/PURPOSES

In patients undergoing cephalomedullary nailing for intertrochanteric hip fractures compared with the conventional technique, we asked: (1) Is the CAS technique associated with a decrease in tip-apex distance (TAD), with less variation and fewer outliers at the standard (25 mm) and lower (15 mm) TAD thresholds? (2) Is the CAS technique associated with a decrease in radiation and operative time? (3) If the CAS technique results in a decrease in TAD, is this decrease associated with a decrease in lag screw cut-out postoperatively?

METHODS

Between Oct 2007 and June 2015, 964 stable and unstable intertrochanteric hip fractures were treated surgically at our institution. Of these, 23% (225 of 964) were isolated, acute intertrochanteric hip fractures managed by a single surgeon. Ninety-five percent (213 of 225) of hip fractures were surgically treated with the same cephalomedullary nail based on the general indications of displaced fractures, poor bone quality, and medical complexity. This same surgeon used a sliding hip screw device in the remaining 5% (12 of 225) of hip fractures for the treatment of nondisplaced and minimally displaced fractures in younger patients with fewer medical comorbidities and good bone quality. Between October 2007 and August 2011, all procedures were performed with conventional lag screw placement (n = 110), and between September 2011 and June 2015, all procedures were performed with CAS (n = 103) for lag screw placement. Postoperative radiographs were missing or unavailable for TAD analysis for 3% (3 of 110) of the conventional technique group and 6% (6 of 103) of the CAS group, so these patients were excluded. The remaining 97% (107 of 110) of conventional procedures and 94% (97 of 103) of CAS procedures were included in the TAD, radiation time, and operative time analysis. For the evaluation of cut-out postoperatively, 24% (26 of 107) of conventional patients and 25% (24 of 97) of CAS patients were excluded due to mortality and/or loss to follow-up at a minimum of 1 year. The remaining 76% (81 of 107) of conventional patients and 75% (73 of 97) of CAS patients were included in the cut-out analysis. A retrospective chart review was performed to obtain the data and then compare TAD, radiation time, operative time, and cut-out between the two cohorts.

RESULTS

The median TAD for the CAS procedures was lower than the median TAD for the conventional procedures (median 13 mm versus median 16 mm, median difference 3 mm; p < 0.001 power for difference = 85%). In addition, the TAD variation was also less for the CAS procedures compared with the conventional procedures (interquartile range [IQR] 4 mm versus IQR 9 mm, IQR difference 5 mm; p < 0.001, power for difference = 98%). A TAD greater than 25 mm was found in 1% (1 of 97) of the CAS procedures and 12% (13 of 107) of the conventional procedures. A difference between the proportions could be detected indicating a lesser chance of a TAD > 25 mm in the CAS cohort (odds ratio = 0.075 [95% confidence interval 0.010 to 0.587]; p = 0.002, power for difference 90%). A TAD > 15 mm was found in 23% (22 of 97) of the CAS procedures and 56% (60 of 107) of the conventional procedures, also indicating a lesser chance of a TAD > 15 mm in the CAS cohort (OR = 0.230 [95% CI 0.125 to 0.423], relative risk for TAD > 15 mm = 0.404 [95% CI 0.270 to 0.606]; p < 0.001, power for difference > 99%). The median radiation time for the CAS cohort was lower than the median radiation time for the conventional cohort (median 1.4 minutes versus median 1.7 minutes, median difference 0.3 minutes; p = 0.002, power for difference = 81%). No difference in median total operating time was found for the CAS procedures compared with the conventional procedures (median 36 minutes versus median 38 minutes, median difference 2 minutes; p = 0.227, power for difference = 18%, power for equivalency = 93%). There was no difference in cut-out noted with the use of the CAS compared with the conventional technique with the numbers available. Based on the current results, the upper 95% probability for a cutout complication ranges from 0% to 5% in the CAS cohort versus 0% to 9% in the conventional cohort (difference of upper 95% CI = 4%).

CONCLUSION

CAS use is associated with a decrease in median TAD with less variation and fewer outliers during cephalomedullary nailing. Compared with the conventional technique, fewer outliers were noted with the CAS at the standard TAD threshold of 25 mm and a lower TAD threshold of 15 mm. Additional research is needed to determine the association of TAD variation and outliers on cut-out and to determine if there is any clinical value to the decrease in TAD variation and outliers noted here. The patient and surgical team are exposed to less radiation with the CAS compared with the conventional technique, but this difference is small and it is unclear if this benefit justifies CAS use. Incorporating CAS into the cephalomedullary nailing procedure is not associated with a change in operative time, so there are no costs or risks associated with increased operative time. More procedures would be needed to provide adequate power to better analyze the risk of lag screw cut-out, allowing a more complete understanding of the value of this technology compared with its cost.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Radiation Exposure of Anaesthetists Visualised by Real-time Dosimetry

BACKGROUND

Chronic exposure to occupational ionising radiation is seen as one reason for elevated cancer prevalence.

OBJECTIVE

The aim of this retrospective study was to evaluate radiation exposure of anaesthetists by real-time dosimetry.

METHODS

Data of 296 patients were analyzed. Ten types of trauma operation procedures including osteosynthesis of upper and lower extremity fractures and minimally invasive stabilisation of traumatic and osteoporotic vertebral fractures were accomplished. Evaluation was performed by an occupational dosimetry system, which visualises anaesthetists radiation exposure feedback compared to surgeons in real-time.

RESULTS

A significantly lower radiation exposure to anaesthetists compared to surgeons was observed in four types of operative procedures: Plate fixation of proximal humerus fractures, osteosynthesis of proximal femoral fractures, stabilisation of traumatic and osteoporotic vertebral fractures. In four types of operations (plate osteosynthesis of proximal humeral, distal radial and tibial fractures and intramedullary nailing of the clavicle), anaesthetists` amount of radiation exceeded one-third of the surgeons' exposure, especially if the C-arm tube was positioned close to the anaesthetists work station at the patients' head.

CONCLUSION

By using the occupational radiation dose monitoring system, radiation exposure to anaesthetists was visualised in real-time during trauma operations. Radiation exposure of anaesthetists depends on the type of operation and the position of the C-arm. The system may help to increase anaesthetists` awareness concerning radiation exposure and to enhance compliance in using radiation protection techniques.

Development and validation of a psychometric scale for assessing healthcare professionals' knowledge in radiation protection

INTRODUCTION

Healthcare professionals must sufficiently understand ionising radiation and the associated protection measures to avoid unnecessarily exposing patients and staff to ionising radiation. Hence, a proper safety culture is important to lowering health risks. The development and establishment of an instrument that can indicate healthcare professionals' understanding/knowledge of radiation protection concepts can greatly contribute to a good safety culture. The purpose of the present study was to develop and psychometrically test the Healthcare Professional Knowledge of Radiation Protection (HPKRP) self-evaluation scale, which was designed to measure the knowledge level of radiation protection by healthcare professionals working with ionising radiation in a clinical environment.

METHODS

The presented research employed a cross-sectional study design. Data were collected from eight Finnish hospitals in 2017. A total of 252 eligible nurses responded to the newly developed HPKRP scale. The face and content validity were tested with the Content Validity Index (CVI). Explorative factor analysis was used to test construct validity, whereas reliability was tested with Cronbach's alpha.

RESULTS

Overall S-CVI for the HPKRP scale was 0.83. Exploratory factor analysis revealed a three-factor model for the HcPCRP scale containing 33 items. The first factor was defined by Radiation physics and principles of radiation usage, the second factor by Radiation protection, and the third factor by Guidelines of safe ionising radiation usage. These three factors explained 72% of the total variance. Cronbach's alpha coefficient for the scale ranged from 0.93 to 0.96.

CONCLUSION

The results provide strong evidence for the validity and reliability of the HPKRP scale. Additionally, educators can use the scale to evaluate healthcare students' understanding in radiation safety before and after education.

Inverted C-arm Orientation During Simulated Hip Arthroscopic Surgery

Background

Fluoroscopic guidance is routinely utilized during hip arthroscopic surgery. Previous studies have shown that the C-arm orientation can significantly affect radiation exposure for both the surgeon and the patient during orthopaedic procedures. However, this has not been previously assessed for hip arthroscopic surgery.

Hypothesis

Using an inverted C-arm during hip arthroscopic surgery will reduce radiation exposure to the patient and surgeon.

Study Design

Descriptive laboratory study.

Methods

A simulation study measured scatter radiation during hip arthroscopic surgery performed in the supine position under fluoroscopic guidance with an anthropomorphic pelvic phantom on a radiolucent operating table. Radiation exposure tested 2 different C-arm orientations: standard and inverted. Testing was performed at 6 locations corresponding to the patient, surgeon's neck, surgeon's waist, surgical technician, anesthesiologist, and radiology technician. Statistical analysis was performed using univariate and multivariate analyses assessing radiation exposure between the C-arm orientations. A risk calculation for carcinogenesis was performed based on reported radiation dosages.

Results

Radiation exposure (in mGy/min) was more than 100-fold higher for the patient compared with the surgeon in both C-arm orientations. The inverted C-arm orientation resulted in a 2.48-fold decrease in patient radiation exposure when compared with the standard orientation (10.8 mGy/min vs 26.8 mGy/min, respectively). There was a small but significant increase in surgeon radiation exposure in the inverted orientation compared with the standard orientation (0.072 vs 0.067 mGy/min, respectively). The patient's carcinogenesis risk was decreased 2.64-fold with the inverted orientation compared with the standard orientation (1.4 × 10^-5 vs 3.7 × 10^-5, respectively).

Conclusion

The inverted C-arm orientation resulted in a 2.48-fold decrease in patient radiation exposure with a 2.64-fold decrease in the carcinogenesis risk compared with the standard orientation. Inadvertently, the inverted orientation provided a 9-cm increase in the surgeon's working area. Our data supported the clinical utilization of the inverted C-arm orientation during hip arthroscopic surgery to minimize patient radiation exposure. Although there was a minimal but significant increase in surgeon radiation exposure with the inverted orientation, we believe that this is negligible when incorporated with standard leaded protective equipment as contrasted with the significant dose reduction for the patient as well as the decreased risk of carcinogenesis and hereditary disorders.

Clinical Relevance

Patients undergoing hip arthroscopic surgery routinely acquire radiation exposure during the use of the C-arm. Measures to minimize radiation via the inverted C-arm orientation will decrease the unnecessary risk to the patient while continuing to allow for optimal treatment.

Intra-operative fluoroscopic radiation exposure in orthopaedic trauma theatre

INTRODUCTION

Radiation exposure from intra-operative fluoroscopy in orthopaedic trauma surgery is a common occupational hazard. References for fluoroscopy use in the operating room for commonly performed operations have not been reported adequately. This study aimed to report appropriate intra-operative fluoroscopy use in orthopaedic trauma and compare the effect of surgery type and surgeon grade on radiation exposure.

METHODS

Data on 849 cases over an 18-month period were analysed retrospectively. Median and 75th centile values for dose area product (DAP), screening time (ST), and number of fluoroscopy images were calculated for procedures where n > 9 (n = 808).

RESULTS

Median DAP for dynamic hip screws for extracapsular femoral neck fractures was 668 mGy/cm2 (ST 36 s), 1040 mGy/cm2 (ST 49 s) for short proximal femoral nail, 1720 mGy/cm2 (ST 2 m 36 s) for long femoral nail for diaphyseal fractures, 25 mGy/cm2 (ST 25 s) for manipulation and Kirschner wire fixation in distal radius fractures, and 27 mGy/cm2 (ST 23 s) for volar locking plate fixation in distal radius fractures. These represented the five commonest procedures performed in the trauma operating room in our hospital. Experienced surgeons utilized less radiation in the operating room than junior surgeons (DAP 90.55 vs. 366.5 mGy/cm2, p = 0.001) and took fewer fluoroscopic images (49 vs. 66, p = 0.008) overall.

CONCLUSIONS

This study reports reference values for common trauma operations. These can be utilized by surgeons in the operating room to raise awareness and perform clinical audits of appropriate fluoroscopy use for orthopaedic trauma, using this study as guidance for standards. We demonstrated a significant reduction in fluoroscopy usage with increasing surgeon experience.

Pulsation and Collimation During Fluoroscopy to Decrease Radiation: A Cadaver Study

Background

Awareness of the harmful effects of long-term low-dose radiation is rising. Many studies have assessed both patient and physician exposure to radiation in association with the use of fluoroscopy in the operating room. However, to our knowledge, previous studies have not assessed, in a detailed fashion, the reduction in radiation exposure that pulsation and collimation provide.

Methods

Seven fresh cadavers were irradiated for 5 minutes with C-arm fluoroscopy with use of standard x-ray and pulsed and collimated x-ray beams. The x-ray sources were placed under the table, over the table, and lateral to the table. Radiation exposure doses were measured at different points, such as the center of the radiation field on the cadaver as well as at the locations of the surgeon's hand and thyroid gland. In addition, Monte Carlo simulation (a physics equation to predict exposure) was performed to estimate the dose reduction and to confirm the experimental results.

Results

The radiation exposure doses associated with the use of pulsed fluoroscopy (8 times per second) were reduced by approximately 30% for the patient and by approximately 70% for the surgeon's hand and thyroid gland as compared with those associated with the use of continuous fluoroscopy. The radiation exposure doses associated with the use of collimated beams were reduced to approximately 65% for the surgeon's hand and thyroid gland as compared with those associated with the use of non-collimated fluoroscopy. These results were consistent with the simulation, and the phenomena could be appropriately explained by physics.

Conclusions

The present study revealed the effectiveness of pulsed and collimated x-ray beams in reducing radiation exposure doses resulting from C-arm fluoroscopy. Surgeons should consider using the techniques of pulsed fluoroscopy and collimation to protect patients and themselves from radiation.

Clinical Relevance

This study presents data regarding the reduction of radiation exposure provided by pulsed fluoroscopy and collimation.

Decreased Radiation Exposure Among Orthopedic Residents Is Maintained When Using the Mini C-Arm After Undergoing Radiation Safety Training

The resident curriculum of the American Board of Orthopaedic Surgery emphasizes radiation safety. Gendelberg showed that, immediately after a program on fluoroscopic safety, residents used less radiation when using the mini C-arm to reduce pediatric fractures. The current study evaluated whether this effect lasted. Residents underwent a new annual 3-hour session on mini C-arm use and radiation. Group A included 53 reductions performed before training. Group B included 45 reductions performed immediately after training. Group C included 46 reductions performed 11 months later. For distal radius fractures, exposure time and amount were 38.1 seconds and 83.1 mR, respectively, for group A; 26.7 seconds and 32.6 mR, respectively, for group B; and 24.1 seconds and 40.0 mR, respectively, for group C. When radiation time and amount were compared between group B and group C, P values were .525 and .293, respectively. When group C and group A were compared, P values were <.05 and <.01, respectively. For both bone forearm fractures, exposure time and amount were 41.2 seconds and 90.9 mR, respectively, for group A; 28.9 seconds and 30.4 mR, respectively, for group B; and 31.2 seconds and 43.6 mR, respectively, for group C. When radiation time and amount were compared between group B and group C, P values were .704 and .117, respectively. When group C and group A were compared, P values were .183 and .004, respectively. No significant difference in radiation exposure was noted immediately after training vs 11 months later. A sustained decrease in radiation exposure occurred after an educational program on safe mini C-arm use. [Orthopedics. 2017; 40(5):e788-e792.].

Fluoroscopic freehand and electromagnetic-guided targeting system for distal locking screws of humeral intramedullary nail

PURPOSE

The current techniques used to lock distal screws for the nailing of long bone fractures expose the surgeons, radiologists and patients to a hearty dose of ionizing radiation. The Sureshot™ Distal Targeting System is a new technique that, with the same results, allows for shorter surgery times and, consequently, less exposure to radiation.

MATERIALS AND METHODS

The study was performed on 59 patients (34 males and 25 females) with a simple humerus fracture diagnosis, type 1.2.A according to the AO classification, who were divided into two groups. Group 1 was treated with ante-grade intramedullary nailing with distal locking screws inserted with a freehand technique. Group 2 was treated with the intramedullary nail using the Sureshot™ Distal Targeting System. Two intra-operative time parameters were evaluated in both groups: the time needed for the positioning of the distal locking screws and the time of exposure to ionizing radiations during this procedure.

RESULTS

Group 2 showed a lower average distal locking time compared to group 1 (645.48″ vs. 1023.57″) and also a lower average time of exposure to ionizing radiation than in group 1 (4.35″ vs. 28.96″).

CONCLUSION

The Sureshot™ Distal Targeting System has proven to be equally effective when compared to the traditional techniques, with the added benefits of a significant reduction in both surgical time and risk factors related to the exposure to ionizing radiation for all the operating room staff and the patient.

Electromagnetic navigation reduces surgical time and radiation exposure for proximal interlocking in retrograde femoral nailing

OBJECTIVES

To compare the time required for proximal locking screw placement between a standard freehand technique and the navigated technique, and to quantify the reduction in ionizing radiation exposure.

METHODS

A fresh frozen cadaver model was used for 48 proximal interlocking screw procedures. Each procedure consisted of insertion of 2 anteroposterior locking screws. Standard fluoroscopic technique was used for 24 procedures, and an electromagnetic navigation system was used for the remaining 24 procedures. Procedure duration was recorded using an electronic timer and radiation doses were documented.

RESULTS

Mean total insertion time for both proximal interlocking screws was 405 ± 165.7 seconds with the freehand technique and 311 ± 78.3 seconds in the navigation group (P = 0.002). All procedures resulted in successful locking screw placement. Mean ionizing radiation exposure time for proximal locking was 29.5 ± 12.8 seconds.

CONCLUSIONS

Proximal locking screw insertion using the navigation technique evaluated in this work was significantly faster than the standard fluoroscopic method. The navigated technique is effective and has the potential to prevent ionizing radiation exposure.

Radiation-free distal locking of intramedullary nails: evaluation of a new electromagnetic computer-assisted guidance system

Distal locking of intramedullary nails (IMNs) is a difficult part of intramedullary nailing (IMN) that could be time-consuming and expose the surgeon, the surgery personnel and the patient to a considerable amount of radiation as fluoroscopy is usually guiding the procedure. Utilization of electromagnetic fields for that purpose offers an attractive alternative. The SURESHOT™ Distal Targeting System (Smith & Nephew, Inc., Memphis, TN, USA) is a novel commercially available radiation-free aiming system that utilizes computerized electromagnetic field tracking technology for the distal locking of IMNs. In order to evaluate the efficacy of the system we conducted the present study. Nineteen patients (six females-thirteen males, mean age 39.5 years, range 17-85 years) with closed diaphyseal fracture of the femur (eight patients) or the tibia (eleven patients) were treated with IMN using the SURESHOT™ Distal Targeting System for the distal interlocking. All targeting attempts were successful at first try and followed by correct positioning of the screws. Mean time for distal locking of tibial IMNs (two screws) was 219sec (range 200-250sec). Mean time for distal locking of femoral IMNs (two screws) was 249 (range 220-330sec). In the current study the SURESHOT™ Distal Targeting System proved to be accurate, fast and easy to learn.