Purpose. To evaluate the use of cutaneous marking of the sacrum for percutaneous iliosacral screw fixation. Iliosacral screw placement is dependent upon spatial perception, multiplanar fluoroscopic imaging, and an appreciation of pelvic anatomy which often makes learning the technique difficult for residents. Cutaneous marking of the sacrum may facilitate iliosacral screw insertion by providing additional cues to the orientation of the sacrum. Method. A cross-over study design was used for placing iliosacral screws in whole cadaver specimens using standardized operative and imaging techniques with and without cutaneous sacral markings. Lateral fluoroscopic imaging and a radio-opaque straight edge were used to trace the lateral profile of the sacrum with a marking pen. Total procedure time and fluoroscopy time were recorded. A total of 14 residents (6 seniors and 8 juniors) each placed two iliosacral screw guide-wires in a total of seven whole cadavers (14 SI joints). Group 1 performed the procedure first with no markings and then with markings. Group 2 performed the procedure first with markings and then without markings. Statistical analysis included T test, Wilcoxon Rank Sum Test, and Signed-Rank Test for Difference (p = 0.05). Participants also reported their opinions on each technique. Results. Mean procedure time for Group 1 was 8.83 minutes (3.77 17.17) and mean fluoroscopy time was 0.77 minutes (0.4 1.2) for the no-marking attempt and 10.33 min (5.88 15.25) and 1.06 min (0.6 2.3) respectively for the marking attempt. Mean procedure time for Group 2 was 11.3 min (6.33 16.5) and mean fluoroscopy time was 1.19 min (0.6 2.3) for the marking attempt and 7.22 min (2.83 17.27) and 0.97 min (0.4 1.8) respectively for the no-marking attempt. There were no significant differences between groups. T test analysis of all marking vs. no marking showed no significant difference for total procedure time (p= O.7020) or fluoroscopy time (p= 0.8297). Wilcoxon Rank Sum Test analysis showed no significant difference for total procedure time (p= 0.4415) or fluoroscopy time (p=0.7486) and Signed-Rank Test for Difference showed no significant difference for total procedure time (p=0.0625) or fluoroscopy time (p=0.1459). Senior residents reported they found the cutaneous marking helpful and would use it again whereas junior residents had mixed feelings on its utility. Conclusion. Cutaneous marking of the sacrum did not significantly impact total procedure time or fluoroscopy time but was generally reported to be helpful for residents learning percutaneous iliosacral screw fixation

Objectives. Percutaneous iliosacral screw placement is a standard, stabilization technique for pelvic fractures. The purpose of this study was to assess the effectiveness of a novel biplanar robot navigation aiming system for percutaneous iliosacral screw placement in a human cadaver model. Methods. A novel biplanar robot navigation aiming system was used in 16 intact human cadaveric pelvises for percutaneous iliosacral screw insertion. The number of successful screw placements and mean time for this insertion and intra-operative fluoroscopy per screw-pair were recorded respectively to evaluate the procedure. The accuracy of the aiming process was evaluated by computed tomography. Results. Sixteen intact human cadaveric pelvises were treated with percutaneous bilateral iliosacral S1 screw placement (32 cannulated screws, diameter-7.3mm, Synthes, Switzerland). All screws were placed under fluoroscopy-guided control using the biplanar robot navigation aiming system (TINAV, GD2000, China). There was no failed targeting for screw-pair placements. Computed tomography revealed high accuracy of the insertion process. 32 iliosacral screws were inserted (mean operation time per screw-pair 56 ± 3 minutes, mean fluoroscopy time per screw-pair 11.7 ± 9 seconds). In post-operative CT-scans the screw position was assessed and graded as follows: I. secure positioning, completely inserted in the cancellous bone (86%); II. secure positioning, but contacting cortical bone structures (9%); III. malplaced positioning, penetrating the cortical bone (5%). Conclusion. This cadaver study indicated that an aiming device–based biplanar robot navigation system is highly reliable and accurate. The promising results suggest that it has the advantages of high positioning accuracy, decreased radiation exposure, operational stability and safety. It can be used not only for the percutaneous iliosacral screw placement but also for other orthopedic surgeries that require precise positioning

There has been a trend towards operative management of pelvic injuries. Posterior pelvic integrity is more important for functional recovery. Percutaneous iliosacral screw fixation is being increasingly preferred for posterior pelvic stabilisation. Outcome reporting for this procedure remains inconsistent and un-standardised. Retrospectively, all percutaneous iliosacral screw fixations done at this institute during a 5-year period (2008–2012) were reviewed. 28 patients, who had had at least 12 months follow-up, were contacted and clinical scoring was done by postal correspondence. Radiographs were measured for displacements and leg-length discrepancy. Possible factorial associations and correlations were investigated. Mean Majeed score was 83 (median 87), mean EQ-Visual Analog Score (EQ-VAS) was 75.5 (median 80) and the two scores were correlated with statistical significance. Tile AO type C injuries produced worse outcomes and patients who'd anterior pelvic fixation did better. Our results show high patient-reported outcomes, excellent radiologically measured reductions and unions. The incidence of complications is very low. There is a significant correlation between the EQ-VAS arm of the EQ5D instrument and the Majeed score in this patient population. Incidence of non-pelvic surgical procedures in these patients was significantly associated with worse outcomes. Leg length discrepancies appeared to increase after patients were fully weight bearing

Minimally invasive placement of iliosacral screws (SI-screw) is becoming the standard surgical procedure for sacrum fractures. Computer navigation seems to increase screw accuracy and reduce intraoperative radiation compared to conventional radiographic placement. In 2012 an interdisciplinary hybrid operating theatre was installed at the University of Ulm. A floor-based robotic flat panel 3D c-arm (Artis zeego, Siemens, Germany) is linked to a navigation system (BrainLab Curve, BrainLab, Germany). With a single intraoperative 3D scan the whole pelvis can be visualised in CT-like quality. The aim of this study was to analyse the accuracy of SI-screws using this hybrid operating theater. 32 SI-screws (30 patients) were included in this study. Indications ranged from bone tumour resection with consecutive stabilisation to pelvic ring fractures. All screws were implanted using the hybrid operating theatre at the University of Ulm. We analysed the intraoperative 3D scan or postoperative computed tomography and classified the grade of perforation of the screws in the neural foramina and the grade of deviation of the screws to the cranial S1 endplate according to Smith et al. Grade 0 stands for no perforation and a deviation of less than 5 °. Grade 1 implies a perforation of less than 2 mm and a deviation of 5–10°, grade 2 a perforation of 2–4 mm and a deviation of 10–15° and grade 3 a perforation of more than 4 mm and a deviation of more than 15°. All patients were tested for intra- and postoperative neurologic complications and infections. The statistical analysis was executed using Microsoft Excel 2010. 32 SI-screws were implanted in the first 20 months after the hybrid operating theatre had been established in 2012. All 30 patients were included in this study (15 men, 15 women). The mean age was 59 years ±23 (13–95 years). 20 patients received a single screw in S1 (66.7%), 1 patient 2 unilateral screws in S1 and S2 (3.3%), one patient 2 bilateral screws in S1 (3.3%) and 8 patients a single screw stabilising both SI-joints (26.7%). 27 screws showed no perforation (84.4%), 1 screw a grade 1 perforation (3.1%) and 4 screws a grade 2 perforation (12.5%). There was no grade 3 perforation. Furthermore there was no perforation of the neural foramina or the ventral cortex in the axial plane of the SI-screws stabilising one SI-joint (24 screws). Only single SI-screws bridging both SI joints showed a perforation of the neural foramina (37% grade 0, 12.5% grade 1, 50% grade 2, 0% grade 3). In the frontal plane 23 screws (71.9%) showed a deviation of less than 5°. In 5 screws a grade 1 deviation (15.6%) and in 4 screws a grade 2 deviation (12.5%) could be found. There was no grade 3 deviation. There were no infections or neurological complications. The high image quality and large field of view in combination with an advanced navigation system is a great benefit for the surgeon. All SI-screws stabilising only one joint showed completely intraosseous placement. Single SI-screws bridging 2 SI-joints intentionally perforated the neural foramina ventrally in 5 cases because of dysmorphic sacral anatomy. This makes image-guided implantation of SI-screws in a hybrid operating theatre a very safe procedure

The royal victoria hospital is a tertiary trauma centre receiving pelvic injury referrals for a population of 1.7 million. The use of ilio-sacral screw fixation with low anterior frame stabilisation has been adopted as the principle treatment for unstable pelvic ring injuries in our institution. We aim to describe our practice and outcomes following the use of percutaneous screw fixation of the pelvis.

The review included standardised assessment of health-related quality of life (SF-36) as well as the Iowa pelvic score and Majeed pelvic injury outcome scores. Data was also collected on associated injuries, post-operative complications, nerve injury and pain scores.

A total case series of 45 patients undergoing percutaneous ilio-sacral screw fixation following traumatic pelvic injury were identified over a 5 year period. Of these 23 were contactable to follow-up or responded to questionnaire review.

The mean follow up was 680 days (range 151–1962). The mean age was 33 (range 18–57).

The mean SF-36 physical and mental scores were 38 and 46 respectively. The mean Majeed score was 69 and Iowa pelvic score was 65. The mean pain score was 3.5 (range 0–7). There were no incidences of deep infection, post-operative PE or nerve injury related to screw insertion.

Patients with isolated pelvic injuries performed better on outcome scoring however the low SF-36 scores highlight the severity of pelvic injuries

Dysmorphic pelves are a known risk factor for malpositioned iliosacral screws. Improved understanding of pelvic morphology will minimise the risk of screw misplacement, neurovascular injuries and failed fixation. Existing classifications for sacral anatomy are complex and impractical for clinical use. We propose a CT-based classification using variations in pelvic anatomy to predict the availability of transosseous corridors across the sacrum. The classification aims to refine surgical planning which may reduce the risk of surgical complications. The authors postulated 4 types of pelves. The “superior most point of the sacroiliac joint” (sSIJ) typically corresponds with the mid-lower half of the L5 vertebral body. Hence, “the anterior cortex of L5” (L5. a. ) was divided to reference 3 distinct pelvic groups. A 4. th. group is required to represent pelves with a lumbosacral transitional vertebra. The proposed classification:. A – sSIJ is above the midpoint of L5. a. B – sSIJ is between the midpoint and the lowest point of L5. a. C – sSIJ is below the lowest point of L5. a. D – pelves with a lumbosacral transitional vertebra. Specific measures such as the width of the S1 and S2 axial and coronal corridors and the S1 lateral mass angles were used to differentiate between pelvic types. Three-hundred pelvic CT scans were classified into their respective types. Analysis of the specific measures mentioned above illustrated the significant difference between each pelvic type. Changes in the size of S1 and S2 axial corridors formed a pattern that was unique for each pelvic type. The intra- and inter-observer ratings were 0.97 and 0.95 respectively. Distinct relationships between the sizes of S1 and S2 axial corridors informed our recommendations on trans-sacral or iliosacral fixation, number and orientation of screws for each pelvic type. This classification utilises variations in the posterior pelvic ring to offer a planning guide for the insertion of iliosacral screws

INTRODUCTION. Isolated injuries of the sacral bone are rare. The pathomechanism of these injuries are usually high velocity accidents or falls from large heights. The computer-assisted implantation of iliosacral screws (SI-screw) becomes more important in the treatment of dorsal pelvic ring fractures. The advantage of the minimal-invasive screw placement is the reduction of the non-union and deep wound infection rate. Another advantage of computer-navigated SI-screw placement is the reduction of intraoperative radiation for the patient and the surgical staff. The purpose of this study was to analyse the position of navigated iliosacral screws. METHODS. In the study group 74 screws (49 patients) were included and radiologically analysed. All screws were implanted using 3D-navigation (BrainLAB Vector Vision, Brainlab, Germany). Navigation was always executed with the same 3D c-arm (ARCADIS Orbic 3D, Siemens, Germany) and navigation system. We determined the grade of perforation and angular deviation in the postoperative CT-scans in all screws. The classification was performed according to Smith et al in 4 grades. Grade 0 implies no perforation and grade 1 a perforation less than 2 mm. Grade 2 correlates a perforation of 2–4 mm and grade 3 a perforation of more than 4 mm. Furthermore the intra- and postoperative complications as well as the body-mass-index, the co-morbidities and the duration of radiation were documented. The statistical analysis was executed using Microsoft Excel 2003. RESULTS. The mean age of the 49 patients was 42.2 years ± 18 (16–79 years). 28 male and 21 female patients were included. 25 patients received a single iliosacral screw in S1. In 19 cases a screw in S1 and S2 was placed on the same side. Four patients got bilateral SI-screws in S1 and another patient received bilateral screw placement in S1 as well as an additional screw in S2. The mean operation time was 100 min ±103 (20–540 min). The isolated time for SI-placement was 50 min ± 20 (20–93 min). The mean radiation time was 3 min ± 1.7 (0.9–7.4 min) (n = 28). Altogether 84% of the screws showed an intraosseous position (grade 0). In the axial plane 7 screws perforated ventrally, 5 screws penetrated the adjacent neural foramen. In the frontal plane the screws showed greater variations, 61% deviated less than 5° (grade 0). In the study group 5 screws needed surgical revision because of either malplacement or postoperative pain. There were no infections or neurological complications. There was no statistical correlation between screw perforation and the body-mass-index. CONCLUSION. The computer-assisted implantation of iliosacral screws is a safe method in relation to screw perforation. It shows a high security and accuracy concerning the ventral and dorsal cortical perforation. There is a frequent angular deviation in the frontal view without appearance of screw perforation or mechanic, neurologic and angiologic complications. The minimal-invasive procedure shows a low postoperative revision rate

Traditionally, unstable anterior pelvic ring injuries have been stabilised with an external fixator or by internal fixation. Recently, a new percutaneous technique of placement of bilateral supraacetabular polyaxial screws and subcutaneous connecting bar to assemble an “internal fixator” has been described. We present the surgical technique and early clinical results of using this technique in twenty-five consecutive patients with a rotationally unstable pelvic ring injury and no diastasis of the symphysis pubis treated between April 2010 and December 2013. Additional posterior pelvic stabilisation with percutaneous iliosacral screws was used in 23 of these patients. The anterior device was routinely removed after three months. Radiological evidence of union of the anterior pelvic ring was seen in 24 of 25 patients at a minimum 6 month follow-up. Thirteen patients developed sensory deficits in the lateral femoral cutaneous nerve (five bilateral) and only one fully recovered. The anterior pelvic internal fixator is a reliable, safe and easy percutaneous technique for the treatment of anterior pelvic ring injuries, facilitating the reduction and stabilisation of rotational displacement. However, lateral femoral cutaneous nerve dysfunction is common. The technique is recommended in cases with bilateral or unilateral pubic rami fractures and no diastasis of the symphysis pubis

Objective. To report clinical results of patients who underwent closed reduction and percutaneous iliosacral screw fixation for Tile Type C fractures. Materials and Methods. Retrospective, we collected data using medical records and images of patients treated in our centre. Prospectively, we followed up patients with two questionnaires. Minimum follow up time was 12 months with the mean being 24 months. 36 patients were followed up with a mean age 34 years (range 14- 65) from 2001-2009. Fracture types included 1 C1-1, 18 C1-2, 26 C1-3. Functional status was assessed using the Majeed pelvic score and the Iowa pelvic Score. Results. Types of injury included 38% road traffic accidents, 16% pedestrians hit by a car, 11% crush injuries, 11% falls from a significant height (>10ft),and 9% forklift injury. 32% of injuries occurred at work. The most commonly associated injury was pubic rami fractures closely followed by spinal injury and femoral fractures. The average Majeed score for those unemployed, pre injury, was 68 (good) and those employed was 67 (fair). The average Iowa score was 71 (good). 36% of patients returned to work, 36% were unable to return to work, 4% retired and, 22% were unemployed pre and post injury. The average visual pain score was 3.9/10 and 20% of patients experience no pain. Surgical complications included 2 non unions requiring open reduction and internal fixation, and 1 wound infection requiring removal of metalwork. Three patients required removal of metalwork due to ongoing back pain, of these 2 patients symptoms improved. Conclusion. Our patients experienced a low rate of complications and had a good functional outcome after undergoing closed reduction and percutaneous iliosacral fixation for Tile Type C fractures