Accuracy of Latarjet graft and screw position after using novel drill guide.

PURPOSE: For the success of Latarjet procedure a correct graft positioning is mandatory. Furthermore, the correct screw placement is important to avoid cartilage damage and soft tissue irritation. Due to a cadaveric experimental study, the accuracy of graft and screw positioning utilizing a novel drill guide for a minimal-invasive Latarjet procedure was analyzed. METHODS: Five human fresh-frozen shoulder specimens have been treated in accordance with the Congruent-Arc Latarjet technique using the glenoid bone loss set (Arthrex, Naples, FL, USA) with 3.75 mm cannulated screws throughout a 5 cm skin incision without detachment of the scapularis tendon. All procedures were performed by one single, experienced shoulder surgeon. The accuracy of graft and screw positioning was assessed due to a CT scan. RESULTS: A noticeable learning curve was noted during the study period as the first surgery took 45 min and the last 33 min. All grafts were correctly positioned with regard to the articular line of the glenoid surface. Impingement with the maximum head circumference was not encountered. The screw positions did not affect the suprascapular nerve. A damage of the graft was not noticed. CONCLUSIONS: The authors can recommend the usage of the new drill guide tested in this study. It seems to be beneficial in the Latarjet procedure and may ease correct graft positioning and prevent screw misplacement. Compared to fully arthroscopically performed Latarjet procedures it provides much steeper learning curve and seems technically easier and quicker to handle.

Significance of clinical examination, CT and MRI scan in the diagnosis of posterior pelvic ring fractures.

INTRODUCTION: Patients with a fracture in the anterior pelvic ring often simultaneously demonstrate pain in the posterior pelvic ring. The aim of the present prospective study was to assess the sensitivity of CT, MRI and clinical examination in the detection of fractures in the posterior pelvic ring in patients with fractures of the anterior pelvic ring diagnosed in conventional radiographs. METHODS: Sixty patients with radiographic signs of an anterior pelvic ring injury were included in this prospective analysis. Following a focused clinical examination of the posterior pelvis, all patients underwent both a CT and then a MRI scan of their pelvis. Two board certified radiologists evaluated the CT and MRI scans independently. To estimate the presence of osteoporosis the Hounsfield units of the vertebral body of L5 were measured in each case. RESULTS: Fifty-three women and seven men, with a mean age of 74.7+/-15.6 years were included into the study. A fracture of the posterior pelvic ring was found in fourty-eight patients (80%) patients using MRI. Fractures of the posterior pelvic ring would have been missed in eight cases (17%), if only CT had been used. Eighty-five percent of the patients with a posterior fracture had an osteoporosis. The majority of the cases suffered from a low energy trauma. Thirty-eight patients (83%) with positive clinical signs at the posterior pelvic ring actually had a fracture of the posterior pelvic ring in the MRI. The clinical examination proved to be equally effective to CT in detecting posterior pelvic ring fractures. CONCLUSION: The significance of both, clinical examination and CT was confirmed in the detection of fractures in the posterior pelvic ring. MRI examination of the pelvis however, was found to be superior in detecting undislocated fractures in a cohort of patients with a high incidence of osteoporosis. Using MRI may be beneficial in select cases, especially when reduced bone density is suspected.

[Surgical treatment of posterior shoulder dislocation: importance of arthroscopy]. / Operative Versorgung der posterioren Schulterluxation: Stellenwert der Arthroskopie.

OBJECTIVE: Posterior dislocations of the shoulder represent a rare injury with frequently occurring soft tissue and/or bony concomitant lesions such as the reverse Hill-Sachs lesion and the dorsal labrum tear. For the combination of these injuries, no evidence-based therapeutic recommendations exist. AIM OF STUDY: Reflecting on two clinical cases and the current literature data, options for the treatment of combined osseous and soft tissue injuries due to posterior dislocation of the shoulder are presented. METHODS: We report two cases of fresh traumatic first-time posterior dislocations that were each explored arthroscopically and subsequently operated using an open technique. In the first case, we performed refixation of the labrum, followed by open osteosynthesis with bone substitution. Treatment of the second case included diagnostic arthroscopy and - after a frustrating attempt to elevate the defect in an arthroscopically assisted retrograde technique - open reconstruction of the humeral head with an allograft. RESULTS: In both cases good clinical outcomes with Constant scores of 79 and 86 points at the 16- and 12-month follow-ups, respectively, were achieved. Radiologically complete integration of the used materials was found. CONCLUSION: These cases show that for the operative treatment of fresh, traumatic posterior shoulder dislocation, it is useful to explore the joint arthroscopically to identify concomitant injuries of the labrum and if necessary treat them. The bony pathology of the humeral head can subsequently be addressed in an open technique, whereby the appropriate treatment should be chosen based on the size of the defect.

Management of traumatic spinopelvic dissociations: review of the literature.

PURPOSE: Spinopelvic dissociation is a rare high-energy injury pattern in adults associated with high morbidity and an increased rate of neurological deficits. The purpose of this article is the conception of fracture type-associated treatment recommendations. METHODS: This article is based on our own experience with spinopelvic dissociations and a review of the current literature. RESULTS: Bilateral vertical plus an optional transverse fracture component configures spinopelvic dissociations as "U"- or "H"-shaped, with the result of a spinopelvic dissociation. "Y"-, "T"- or "II"-shaped fractures do not necessarily belong to this entity but can be subsumed to this entity in a wider sense. The surgical treatment of these injuries remains challenging. Initial haemodynamic stabilisation represents the main goal of primary care until definitive treatment can be performed. Anatomical reduction is demanding and even more complex in fracture areas with large comminution. Surgical treatment options depend on the fracture type, including transsacral screws, sacral banding and spinopelvic fixation, plus combinations of these procedures. CONCLUSIONS: Spinopelvic dissociations remain highly complex injuries. "U"- and "H"-shaped fractures usually require triangular fixation, whereas "II"-, "Y"- and "T"-shaped fractures might be sufficiently stabilised with transsacral screws.

Sacroplasty in a cadaveric trial: comparison of CT and fluoroscopic guidance with and without balloon assistance.

Sacral insufficiency fractures can cause severe, debilitating pain to patients concerned. The incidence of this fracture type correlates with the appearance of osteoporosis in the elderly population. A polymethylmethacrylate (PMMA) cement injection procedure called sacroplasty has been recently described as an optional method for the treatment of this fracture type. However, the correct cement placement in the complex anatomical structure of the sacrum is a surgical challenge. The aim of the study is to compare the precision, safety, and radiation exposure of standard multiplanar fluoroscopy and computed tomography (CT) guidance for PMMA application to the sacrum using both balloon-assisted sacroplasty and conventional sacroplasty. A controlled experimental investigation in a human cadaver trial has been performed. Two imaging and two application modalities to monitor percutaneous PMMA injection to the sacrum were examined. The application forms were randomized from side to side of the pelvis. We found less cement extravasation in the CT-guided groups, but also a significant higher radiation exposure (P < 0.05) by using CT guidance. The conventional fluoroscopy-guided sacroplasty revealed the shortest procedure time (incision to closure time) of all treatment groups (P < 0.01). These findings show no difference regarding cement extravasation between ballon-assisted and conventional sacroplasty. Further, in comparison to fluoroscopy-assisted technique, the CT-guided cement injection seems to decrease the risk of cement extravasation, irrespective of the use of an additional balloon assistance. However, we have to consider a greater radiation exposure using CT guidance. Further investigations will proof the suitability in the normal course of clinical life.

The treatment of intertrochanteric fractures: results using an intramedullary nail with integrated cephalocervical screws and linear compression.

OBJECTIVE: A new device for the treatment of intertrochanteric fractures that uses 2 cephalocervical screws in an integrated mechanism allowing linear intraoperative compression and rotational stability of the head/neck fragment has been developed. The aim of this study was to describe the results using this device for the treatment of stable and unstable intertrochanteric fractures. DESIGN: Prospective, consecutive. SETTING: Academic Trauma Center. METHODS: Between March 1, 2005, and July 31, 2006, 100 consecutive patients with an intertrochanteric fracture were treated with a new trochanteric antegrade nail (InterTan; Smith-Nephew, Memphis, TN). All living patients were followed up for a minimum of 1 year postoperatively (range 12-27 months). Clinical and radiographic examinations were performed until healing and at the 1-year anniversary of the index procedure. Healing, pain with ambulation, return to activities of daily living, the modified Harris hip score, and Barthel Index were used to evaluate outcomes. RESULTS: The mean age of the patients was 81.2 (+/-11.3) years. Thirty-seven patients died, 12 were too infirmed for follow-up, and 3 could not be located, leaving 48 patients available for final evaluation. The average surgical time was 41 minutes (13-95 minutes). This rose significantly with the complexity of the fracture (OTA/AO classification: A1 versus A3, P = 0.016). All fractures healed within 16 weeks (range 10-16 weeks). Radiographic analysis at healing revealed no loss of reduction, no uncontrolled collapse of the neck, no nonunions, no femoral shaft fractures, and no implant failures. Two cases in the series were poorly reduced and settled into varus malalignment. There was no varus malposition seen in the remaining 46 fractures. The mean prefracture Harris hip score (75.1 +/- 13.4) was significantly reduced at the time of follow-up (70.3 +/- 14.5, P = 0.003); 58% of the patients recovered their prefracture status. No significant difference was seen for the Barthel Index. CONCLUSIONS: The InterTan device appears to be a reliable implant for the treatment of intertrochanteric femoral fractures. Its design provides for stability against rotation and minimizes neck malunions (shortening) through linear intraoperative compression of the head/neck segment to the shaft. As a result of the negligible complication rate and improved clinical outcomes, this implant is now the standard treatment for all intertrochanteric fractures at our institution.

[Periprosthetic fractures. Long-term results after plate osteosynthesis stabilization]. / Periprothetische Femurfrakturen. Langzeitergebnisse nach plattenosteosynthetischer Stabilisierung.

BACKGROUND: Due to the increasing age of patients and the rising number of joint replacements, the incidence of periprosthetic fractures (PPF) is also increasing. The treatment should be selected with knowledge of the prefracture interface status and the type of fracture involved. The aim of this study was to evaluate our treatment of PPF with long-term follow-up. PATIENTS AND METHODS: From 1988 to 2006, 99 patients with PPF were treated in our department. In 86 cases a plate osteosynthesis was used. After a mean time of 7.3+/-2.8 years, we studied 56 patients and monitored their complications. RESULTS: The most diagnosed fracture was Johansson type III (44%). Seventy-one patients were treated with a conventional and 15 with locking-plate osteosynthesis. In 15 cases (17.5%) we found severe complications (3 breaks and 3 dislocations of the plates, 6 cases of pseudarthrosis, 2 deep wound infections, and 1 case of postoperative bleeding). CONCLUSION: Due to the minor frequency of severe complications, plate osteosynthesis of a periprosthetic fracture with a loosened interface is a good therapeutic option for individual patients, particularly for geriatric patients and those without disorders specific to a loosened interface.

[Early interdisciplinary geriatric rehabilitation after hip fracture : Effective concept or just transfer of costs?]. / Die geriatrische Frührehabilitation nach hüftgelenknahem Oberschenkelbruch: Nachhaltiges Konzept oder lediglich Kostenverschiebung?

BACKGROUND: Modern strategies for postoperative care of patients with hip fractures include early discharge from the acute care hospital to inpatient interdisciplinary rehabilitation facilities. Whether these programs are effective for the patients and improve their long-term outcomes or if they simply transfer costs, with a reduction of the inpatient days in the acute care hospital, is currently under discussion. PATIENTS AND METHODS: This prospective study included 282 patients with hip fracture admitted to our trauma center were included into the prospective study. The mean patient age was 86+/-8 (65-110) years. All patients were treated operatively. After a mean of 12+/-9 days, the patients underwent inpatient interdisciplinary geriatric rehabilitation for a mean of 27+/-13 (4-103) days. The primary outcome measure was their activities of daily living (Barthel index) before, at the end of rehabilitation, and 1 year after trauma. In addition, patient-related variables were correlated with the Barthel index. RESULTS: With discharge from the acute care hospital, the Barthel index was 42+/-20 points and it increased during rehabilitation to 65+/-26 points. One year later the Barthel index was 67+/-28 points. Ninety percent of patients improved their Barthel index during rehabilitation. Within 1 year, 40% of patients deteriorated in their activities of daily living. Fifty one percent of patients were reintegrated back to their homes. Patients who lived at home before trauma and were reintegrated back to their homes had a significant higher Barthel index (75+/-24) 1 year after trauma than patients who were living in a nursing care facility before the trauma (Barthel index 52+/-27). The variables of age, level of cognition, and type of fracture had no influence on the long-term outcome. An extension of rehabilitation above the mean time period did not improve the sustainable clinical outcome. CONCLUSION: Postoperative inpatient rehabilitation programs enhance short-term activities of daily living. In particular, patients who lived at home before the trauma and were reintegrated back home benefited in perpetuity from geriatric rehabilitation. A policy for early discharge to geriatric rehabilitation is associated with extension of overall hospital stay. This association along with the related increased health care costs should be weighed against the sociofunctional effectiveness of these programs.

Comparison of open versus percutaneous pedicle screw insertion in a sheep model.

Minimally invasive surgery has become more and more important for the treatment of traumatic spine fractures. Besides, some clinical studies, objective data regarding the possible lower damage to the surrounding tissue of the spine is still missing. Here we report a sheep model where we compared a percutaneous versus an open approach for dorsal instrumentation with pedicle screws to the spine. Twelve skeletally mature sheep underwent bilateral pedicle screw fixation at the L4-L6 level. Forty-eight pedicle screws were bilaterally inserted into the pedicles and connected with rods using either an open dorsal standard or a percutaneous approach. Operation time, blood flow, compartment pressure, radiation time, loss of blood, laboratory findings and EMG were evaluated to objectify possible advantages for the percutaneous operation technique. Loss of blood and the distribution of CK-MM as a marker for muscle damage were significantly lower in the percutaneous group. However, radiation time was significantly longer in the percutaneous group. Other parameters like compartment pressure, blood flow and also measurement of the EMG at different time points did not reveal significant differences. Based on the results we found in the present study, percutaneous screw insertion can bring moderate advantages but it should be noted that essential functional deficits to the muscle could not be detected.

[CT-guided balloon-assisted sacroplasty. Preliminary results of a feasibility study]. / CT-gesteuerte Sakroplastie unter Verwendung insufflierbarer Ballons. Ergebnisse einer Machbarkeitstudie.

OBJECTIVE: The procedure of sacroplasty was introduced recently and involves the percutaneous application of cement to the sacral bone. Currently there are no standardized data available reflecting clinical results such as leakage rates or other complications. The aim of this study was to evaluate the feasibility and results of a balloon-assisted, CT-guided cement application in a controlled experimental approach. MATERIAL AND METHODS: The trials were conducted on preserved human cadaveric specimens (n=6). The cement application was supported by kyphoplasty balloons (Kyphon) on the right hand side, and was performed without balloons on the opposite side. CT scans were obtained for preoperative planning and postoperative assessment, while CT fluoroscopy was used for intraoperative guidance (Philips Brilliance 64). RESULTS: The procedure revealed a good feasibility with an average procedure time of 36.9+/-2.4 min (range 33.1-38.9). The chosen scan protocol produced the following effective doses: 0.99 mSv in females and 0.63 mSv in males per scan and 0.33 mSv (females) and 0.25 mSv (males) per CT fluoroscopy image. Extraosseous cement spreading was not observed after both balloon-assisted and conventional application. CONCLUSION: The CT-guided technique presented in this study enables surgeons to perform sacroplasty with high precision and moderate radiation exposure. Further clinical studies are necessary to show if the balloon-assisted cement application can promote lower leakage rates than the conventional technique in patients with sacral fractures.

[Distal fracture of the humerus]. / Distale Humerusfraktur.

Independently of lacerated anatomic structures, the ensuing fracture type, concomitant injuries around the joint, the primary aim in treating distal humeral fractures is the restoration of a painfree, mechanically loadable elbow that has a free range of motion. To achieve these goals the fracture and its associated injuries have to be adequately diagnosed, adequately surgically treated, and after reconstruction must undergo an early physical therapy (PT) protocol. Adequate diagnostics, except for standard X-ray films, include in most cases an additional preoperative CT for evaluation and planning of the surgical approach. Adequate surgical treatment entails anatomic reconstruction and stable fixation via an approach that causes a minimum of additional iatrogenic injury to the adjacent soft tissues. Adequate PT is synonymous with early onset of movement, i.e. as early as the 1st postoperative day if the fixation is stable enough. However, a demanding problem is the increasing number of osteoporosis-associated distal humeral fractures in the elderly population with the development of complex fracture types, partly due to poor bone quality, that are not easily addressed and might lead to unsatisfactory results even after applying standardized protocols including anatomically contoured angular stable plates.

[Consequences of occult insufficiency fractures of the sacrum]. / Folgen der okkulten Insuffizienzfraktur des Os sacrum.

Low back pain disorders of the elderly can potentially be caused by sacral insufficiency fractures due to osteoporosis, radiation necrosis or seldom malignant processes. In our institution an increasing numbers of patients suffering from osteoporotic sacral insufficiency fractures could recently be observed. In a case report study clinical symptoms, diagnostic procedures as well as therapeutic options are discussed.

[Balloon assisted cement application for stable fixation of pedicle screws in osteoporosis]. / Ballonassistierte Zementaugmentation zur stabilen Pedikelschraubenverankerung bei Osteoporose.

In Germany more than 40,000 patients suffer from osteoporotic vertebral fractures every year. Most of these fractures do not require operative stabilisation. However, if surgical stabilisation is necessary, stable fixation of transpedicular implants will be difficult to obtain. In a case study we report on the possibility of a kyphoplasty-guided technique for stable pedicle screw fixation.

[Percutaneous, 2D-fluoroscopic navigated iliosacral screw placement in the supine position: technique, possibilities, and limits]. / Perkutane, 2D-fluoroskopisch navigierte Sakrumverschraubung in Rückenlage: Technik, Möglichkeiten und Grenzen.

OBJECTIVE: In pelvic surgery, computer-assisted procedures are currently used predominantly for percutaneous iliosacral screw placement. The aim of this study was to evaluate the possibilities and limits of a 2D-fluoroscopic navigated procedure used for this indication. METHODS: A consecutive series of patients with non or slightly displaced injuries of the posterior pelvic ring were prospectively investigated. Cannulated cancellous screws of 7.3 mm were percutaneously implanted in the supine position. The navigated procedure was performed using an active optoelectronical system and a 2D C-arm. Target parameters were practicability, precision and intraoperative radiation exposure time compared to patients treated using a non-navigated technique. RESULTS: In a 15 month period, 35 screws were implanted in 20 patients. The average procedure took 36.2+/-12.5 min (range 18-62 min), with a fluoroscopic time of 0.9+/-0.3 min (range 0.6-1.8 min) per screw. The displacement rate was 8% (n=3/35, CI 1.8-23.0). Compared to retrospectively selected patients treated using a non-navigated technique (n=13), a significant increase in procedure time (P=0.01), a significant decrease of radiation exposure time (P<0.001) and a decreased displacement rate (P>0.05) were observed in the navigated group. CONCLUSION: The 2D-fluoroscopic navigated procedure used in this study can be recommended for percutaneous stabilisation of non or minor displaced injuries of the posterior pelvis. This procedure reduces intraoperative radiation exposure and improves intraoperative orientation but does not crucially enhance the precision of screw placement compared to the non-navigated technique. Finally, it is limited by its poor image resolution and lack of three-dimensionality.

[Prolonged vascular complications with subsequent finger necrosis after humeral head luxation fracture in the elderly]. / Protrahierte Gefässkompromittierung mit konsekutiver Langfingergangrän nach Humeruskopfluxationsfraktur des alten Menschen.

Fractures of the proximal humerus represent a typical injury of the elderly. Additional lesions of nerves or arteries are rare and there is only little information in the literature on the co-occurrence of proximal humerus fractures and compromised peripheral circulation which could lead to the loss of the upper extremity. To prevent damage to the injured limb, it is necessary to invent and initiate a standardized algorithm involving trauma care matching the special needs of this combined injury.

[16-Row multidetector CT of the pelvis after iliosacrally inserted osteosynthetic screws: experimental study of dose adjustment on preserved human cadaver specimens]. / 16-Zeilen-Spiral-CT des knöchernen Beckens nach Schraubenosteosynthese der iliosakralen Gelenke--Untersuchungen zur Dosisanpassung in einem Ex-vivo-Modell.

PURPOSE: The study was performed to assess the necessity of dose adjustment (kV or mAs (eff.)) in 16-slice CT (MDCT) in postoperative controls of iliosacrally inserted osteosynthetic screws (OS) on preserved human cadaver specimens. The minimal tube settings for diagnostic imaging of the pelvic bone were analyzed and the effective doses and important organ doses were calculated. MATERIALS AND METHODS: 16 preserved human cadaver specimens with transiliac osteosynthetic screws were scanned on a 16-slice CT (collimation 16 x 0.75 mm, pitch 0.7) with 10 different tube settings (35, 50, 75, 100, 150 mAs (eff.) and 120 and 140 kV). 32 datasets (blinded for name and scan parameters) with and without OS were independently evaluated by four observers. The 10 series were sorted by subjective image quality (image noise, contours, artifacts), and the series with the lowest but still diagnostic quality was selected. The statistical analysis included multi-rater-kappa-test and Wilcoxon test for paired samples. RESULTS: The multi-reader agreements for sorting the series were fair (kappa = 0.38). The agreements in comparing the lowest diagnostic image qualities were slight to fair (kappa = 0.08-0.23). The paired sample test comparing the lowest diagnostic image quality with and without OS showed no statistical significance (p = 0.29). 87.5 % of the readouts (n = 64 [16 examinations, 4 readers]) with OS and 78.1 % of those without OS could be adequately diagnosed using the three series with the lowest effective doses (0.9-1.4 mSv for men, 1.4-2.0 mSv for women; 120 kV-35 mAs (eff.), 120-50, 140-35). CONCLUSION: MSCT scans of the pelvic bone can be performed with very low effective doses. It is not necessary to adjust tube settings when imaging bones with osteosynthetic screws. If the concept for the control of the pelvic osteosynthetic screw position includes more than 2 conventional films (for example anterioposterior view with additional inlet and outlet views), a low dose CT is preferable to conventional radiography.

[Computer-assisted screw placement into the posterior pelvic ring: assessment of different navigated procedures in a cadaver trial]. / Computerassistierte Verschraubung des hinteren Beckenrings : Systematischer Vergleich verschiedener Navigationsverfahren am Kadaverpräparat.

OBJECTIVE: Computer-assisted procedures have recently been introduced for navigated iliosacral screw placement. Currently there are only few data available reflecting results and outcome of the different navigated procedures which may be used for this indication. We therefore evaluated the features of a new 3D image intensifier used for navigated iliosacral screw placement compared to 2D fluoroscopic and CT navigation. MATERIALS AND METHODS: Twenty fixed human cadavers were used in this trial. Cannulated cancellous screws were percutaneously implanted in the supine position in four treatment groups. An optoelectronic system was used for the navigated procedures. Screw placement was postoperatively assessed by fluoroscopic 3D scan and CT. The target parameters of this investigation were practicability, precision as well as procedure and fluoroscopic time per screw. RESULTS: All navigated procedures revealed a significant loss of time compared to non-navigated screw placement (2D: p<0.001, 3D: p>0.05, CT: p<0.001). Simultaneously a significant decrease of radiation exposure time was observed in the navigated groups (p<0.001 each). The misplacement rate was 20% in the non-navigated and the 2D fluoroscopic navigated group each. Procedures providing 3D imaging of the posterior pelvis did not produce any screw misplacement (p>0.05). However, the CT procedure was associated with time-consuming registration and high rates of failed matching procedures. CONCLUSION: Our data show a clear benefit of using C-arm navigation for iliosacral screw placement compared with the CT-based procedure. While both fluoroscopy-based navigation procedures decrease intraoperative radiation exposure times, only 3D fluoroscopic navigation seems to improve the precision compared to non-navigated screw placement.

[On the problem of halo vest treatment in the elderly. Results of a retrospective analysis]. / Zur Problematik des Halofixateurs beim alten Patienten. Ergebnisse einer retrospektiven Untersuchung.

INTRODUCTION: The treatment of unstable cervical spine injuries with the halo vest represents an established procedure. So far no data reflecting the quality of life of patients following a halo vest treatment are available. Elderly people make up a large part of the inpatients in our hospital. Therefore special attention is payed to this group of patients in this study. METHODS: In this study 41 patients (average age of 51.8 +/- 23.5 years) with an unstable injury of the upper cervical spine were investigated. All of them underwent a halo vest therapy in our hospital during 1988-2003. The health-related quality of life was assessed in the mean 8.0 years after the trauma by using the SF-36 Health Survey. Additionally, the incidence of complications and the union rate over time were observed. RESULTS: The evaluation of the data obtained from the SF-36 revealed a reduced quality of life in the patient group in comparison to the reference population. This was particularly apparent in patients older than 60 years. The fracture healing under halo vest treatment was comparably slow. In 17% of the cases no fracture union was obtained after 12 weeks. This was only seen for patients older than 60 years. The complication rate associated to the halo vest amounted to 43% and was independent of age. CONCLUSION: The treatment of unstable fractures of the upper cervical spine with a halo vest results in a prolongated fracture healing for elderly people. Furthermore a halo vest therapy reduces the health related quality of life. Therefore, even for elderly patients an internal osteosynthetic stabilization of an unstable injury of the upper cervical spine should be considered if indicated.

Computer-assisted screw insertion into the first sacral vertebra using a three-dimensional image intensifier: results of a controlled experimental investigation.

Currently there are few data available regarding the application and efficacy of computer-assisted procedures in the sacral spine. In order to optimize and standardize this procedure, a controlled experimental investigation has been performed. The aim of the study is to systematically assess the efficacy of a novel three-dimensional image intensifier used for navigated transiliac screw insertion into the first sacral vertebra. Screws were inserted iliosacrally into the first sacral vertebra of preserved human cadaver specimens. The instrument navigated procedure was performed with the "Siremobil Iso-C(3D) " (Siemens Medical Solutions) and the "Navigation System" by Stryker. The accuracy and quality of the imaging procedure as well as the fluoroscopic exposure times were measured. These results were compared to three control groups (CT-based navigation, C-arm navigation, and fluoroscopic guidance). In each group a total amount of 20 screws was implanted. Screw position was postoperatively assessed by Iso-C(3D) or CT-scan. The navigated procedure using the Iso-C(3D) provided good feasibility characteristics without requiring a specific matching process. It revealed the shortest procedure time of all navigated procedures and significantly decreased fluoroscopic time compared to C-arm navigation and fluoroscopic guidance. Furthermore, Iso-C(3D) navigation showed no screw malposition and was in this regard superior to C-arm navigated and fluoroscopic guided procedures. The quality of imaging was sufficient for accurate placement, but did not share the high-resolution level of CT-based navigation. These findings indicate that application of the Iso-C(3D) for navigated transiliac screw insertion into S1 can be recommended as a feasible and safe technique, enabling the surgeon to reduce procedure and fluoroscopic time. Further progress in improving the quality of the Iso-C(3D) image should be attempted.