inaugural pass accuracy of guide telegram interpolation. The decision of the optimize collar insertion point and guidebook wire placement for the femoral neck prison guard required respectively 4.0 and 4.1 attempts in the conventional group, whereas alone 1.0 undertake was performed under navigate guidance for both .
radiation exposure. Using the standard operational procedure, on average of 33 ± 8.8 fluoroscopic images with a fluoroscopy exposure time of 17.4 ± 4.6 seconds compared to only 2.6 ± 1.1 images with a fluoroscopy vulnerability time of 1.5 ± 0.5 seconds were necessity for the voyage Gamma3 complete interpolation .
No significant difference was observed for the overall procedure time in our experimental set up ( group I : 584 ± 99.2 seconds vs. group II 662 ± 64.9 seconds ). however evaluating the different steps of the procedure, a reduction for all navigated guide wire placements ( clock save : 51 % to determine the interpolation point of nail, 74 % to align the femoral neck screw position ) and the controls of plant insertion ( fourth dimension preservation : 35 % for the nail ; 23 % for the femoral neck screw ) were discernible. This is chiefly caused by the virtual navigate control in two acquired images only, whereas in the conventional technique several images in two orthogonal projections are mandatary for each footstep ( both lead wires, american samoa well as the complete and femoral neck screw interpolation ). however this decrease of operative clock time was neutralized by extra navigation specific steps, like the calibration of instruments, the placement of a dynamic mention base and the learning of the two fluoroscopic images for the navigate procedure. Using an optimize seafaring workflow with calibration of instruments before the function procedure will be started or parallel to the operation by the nurse, a far decrease of function time by 10,8 % can be expected ( group I : 584 ± 99.2 seconds vs. group II 520 ± 48,8 seconds ). In all steps necessary for both operational procedures, that are independent of fluoroscopic or navigated control ( like cannulated drillings to open the nail insertion point ( p= 0,15 ) and to prepare the femoral neck screw duct ( p= 0,48 ), deoxyadenosine monophosphate well as placement of the distal lock fuck ( p= 0,78 ) ), no meaning differences were observed. All Gamma3 nails in both groups were accurately placed without any malposition. No differences were observed for the beggarly tap – vertex – outdistance and the status of the femoral neck fuck in the postoperative CT scans. The extra fluoroscopic images – lone acquired after each template electrify placement to evaluate the navigation accuracy – showed an exact congruity of the plan on the navigation organization display and the concluding guide electrify side ( Figure 3, Figure 4 ). The use of 2D-fluoroscopic based navigation decreases the radiation exposure for the patient and the operate team substantially during Gamma3 collar insertion. For all function steps, that need fluoroscopic see of lead telegram or plant placement, a reduction in procedure clock time was observed, but was equalized by extra seafaring specific steps, like calibration of instruments, fixation of the dynamic citation al-qaeda and learning of the two fluoroscopic images. The final accuracy for the 20 breeze through insertions was alike and autonomous of the conventional or navigate technique used.
however, surgical navigation seems to be a bright procedure for the insertion of Gamma3 nails, as reported in this report for the foremost clock. specially, the 93 % reduction of fluoroscopic images during the nail insertion is one of the most authoritative benefits, as reported for navigate screw fixations in most experimental and clinical studies ( 87 % ), a well as the navigate interpolation of dynamic hip screws ( 75 % ) [ 9, 10 ]. Whereas the patient is only once exposed to radiation only once, the operate team and predominantly the hands of the surgeon are in close proximity to the radiation shine every day [ 4 ]. furthermore, the frequent movements of the c-arm in the antero-posterior and axial projections during the standard procedure may jeopardize the sterility of the operational field and is associated with increased operate on time. One drawback of most navigation procedures is the drawn-out operate time, leading to minor adoption of most surgeons. specially for surgical procedures in older patients with several comorbidities this is of relevant business. In contrast to the recently published studies ( mesa 2 ), no increase of routine time was observed by use of a navigation system compared to the standard technique. A likely beginning for far time savings is the calibration of instruments before starting the routine, ampere well as faster surface referencing with address base fixation by velcro-tapes and unfold films, which is under evaluation for accuracy at the moment .Table 2
Studies of navigation-assisted surgery of the proximal femur
Full size table amazingly the final examination preciseness for the Gamma3 breeze through interpolation did not differ in both groups, but using the voyage approach a first gear fall accuracy was observed for the placement of guide wires ( compared to 4 attempts for determination of the nail interpolation period and 4.1 attempts for the cannulate femoral neck screw interpolation ). versatile studies have identified the “ first passing accuracy ” of guide wire placement as a relevant advantage of navigation procedures [ 3, 11 ]. Beside a reduction of procedure time, a reduce incidence of incorrect drillings prevents weakening of the lateral lens cortex and of the cancellate bone in the femoral neck and thereby may reduce the risk for translation of the femoral neck screw [ 5, 12 ]. In addition, after multiple unsuccessful attempts of lead wire placement the risk of guide cable slipping into the old drill canals increases with each correction manoeuver. Some limitations of the cogitation have to be considered before the voyage routine can be used in clinical settings :
first, an alternate non-invasive fixation of the active reference book base should be preferred to prevent consociate morbidities, such as iatrogenic fractures, heterotopic ossifications and soft tissue damage, as reported for different applications of seafaring in orthopedic surgery [ 13 ]. second, unintended movements of the femoral headway fragment in relative to the femoral shaft after image skill will not be detected in the navigate technique. Therefore we recommend extra fluoroscopic images, first to control the final guide wire placement for the femoral neck fuck and second during the femoral neck screw insertion to visualize a potential fracture displacement by femoral head rotation. third, the procedures were performed by a surgeon experienced in seafaring operation and therefore the measured parameters do not represent the well-known eruditeness curve of inexperienced surgeons, as reported in early studies [ 9 ] .