[Intraoperative virtual implant planning for volar plate osteosynthesis of distal radius fractures]. / Intraoperative virtuelle Implantatplanung bei der volaren Plattenosteosynthese distaler Radiusfrakturen.

BACKGROUND: Digital planning of implants is in most cases conducted prior to surgery. The virtual implant planning system (VIPS) is an application developed for mobile C-arms, which assists the virtual planning of screws close to the joint line during surgery for treatment of distal radius fractures with volar plate osteosynthesis. The aim of this prospective randomized study was to acquire initial clinical experiences and to compare the VIPS method with the conventional technique. METHOD: The study included 10 patients for primary testing and 30 patients with distal radius fractures of types A3, C1 and C2, divided in 2 groups. In the VIPS group, after placement of the plate and fracture reduction, a virtual 3D model of the plate was matched with the image of the plate from the fluoroscopic acquisition. Next, the length and position of the screws close to the joint line were planned on the virtual plate. The control group was treated with the same implant in the conventional way. Data were collected regarding screw replacement, fluoroscopy and operating room (OR) times. RESULTS: The VIPS group included six A3, one C1 and eight C2 fractures, while the control group consisted of six A3 and nine C2 fractures. Three screws were replaced in the VIPS group and two in the control group (p = 0.24). The mean intraoperative fluoroscopy time of the VIPS group amounted to 2.58 ± 1.38 min, whereas it was 2.12 ± 0.73 min in the control group (p = 0.26). The mean OR time in the VIPS group was 53.3 ± 34.5 minutes and 42.3 ± 8.8 min (p = 0.23) in the control group. CONCLUSION: The VIPS enables a precise positioning of screws close to joint line in the treatment of distal radius fractures; however, for routine use, further development of the system is necessary.

Comminuted Fracture of Elbow - Ostheosynthesis vs. Total Joint Replacement.

Comminuted fractures of the elbow are very rare and in most cases very complex and the successful treatment can be a challenge for the treating surgeon. Due to the elbow joint's complex functional anatomy, the multi-fragmentary nature of many fractures and concomitant destabilizing associated injuries, comminuted fractures of the elbow still present a serious challenge for the orthopedic surgeon. Especially in more severe communicated injuries an osteosynthesis or endoprosthesis must be discussed with the patient. There is a lack of clear treatment recommendations based on solid evidence. An overview of the literature including a treatment algorithm to guide decision making for the distal humeral fracture in the adults is presented and own results are analyzed. Key words: comminuted fracture of elbow, total joint replacement of the elbow, elbow prosthesis, elbow arthroplasty, distal humeral fracture.

Is Whole-Body Computed Tomography the Standard Work-up for Severely-Injured Children? Results of a Survey among German Trauma Centers.

PURPOSE OF THE STUDY: Whole-body computed tomography is accepted as the standard procedure in the primary diagnostic of polytraumatised adults in the emergency room. Up to now there is still controversial discussion about the same algorithm in the primary diagnostic of children. The aim of this study was to survey the participation of German trauma-centres in the care of polytraumatised children and the hospital dependant use of whole-body computed tomography for initial patient work-up. MATERIAL AND METHODS: A questionnaire was mailed to every Department of Traumatology registered in the DGU (German Trauma Society) databank. RESULTS: We received 60,32% of the initially sent questionnaires and after applying exclusion criteria 269 (53,91%) were applicable to statistical analysis. In the three-tiered German hospital system no statistical difference was seen in the general participation of children polytrauma care between hospitals of different tiers (p = 0.315). Even at the lowest hospital level 69,47% of hospitals stated to participate in polytrauma care for children, at the intermediate and highest level hospitals 91,89% and 95,24% stated to be involved in children polytrauma care, respectively. Children suspicious of multiple injuries or polytrauma received significantly fewer primary whole-body CTs in lowest level compared to intermediate level hospitals (36,07% vs. 56,57%; p = 0.015) and lowest level compared to highest level hospitals (36,07% vs. 68,42%; p = 0.001). Comparing the use of whole-body CT in intermediate to highest level hospitals a not significant increase in its use could be seen in highest level hospitals (56,57% vs. 68,42%; p = 0.174). CONCLUSION: According to our survey, taking care of polytraumatised children in Germany is not limited to specialised hospitals or a defined hospital level-of-care. Additionally, there is no established radiologic standard in work-up of the polytraumatised child. However, in higher hospital care -levels a higher percentage of hospitals employs whole-body CTs for primary radiologic diagnostics in polytraumatised children.

Humerus shaft fractures - where are we today?

Humeral shaft fractures account for about 1-3% of all fractures. These fractures are regarded as the domain of non-surgical management. This is certainly still the contemporary view but there is an obvious trend towards surgical stabilization. Surgical treatment of humeral shaft fractures has nonetheless been greatly facilitated by the development of new implants. In particular, a new generation of nails that general permit immediate mobilization have become available for improved management of longitudinal and multi-segmental fractures. Retrograde and antegrade nails have advantages and disadvantages and selection procedure is often based on the distal or proximal location of the fracture. Plates also offer an alternative for certain indications and have advantages at the proximal and distal shaft in particular. If there is primary lesion of the radial nerve, exploration is not very advisable, but in the absence of remission exploration can be conducted after several months with the same degree of success. Since the published literature offers no comparative studies with a high level of evidence, our statement can only be regarded as an up-to-date recommendation in the hope that future prospective randomized studies will address this issue.

Clinical outcome after surgical treatment of transitional fractures of the distal tibia in children.

PURPOSE OF THE STUDY: Fractures affecting a partially closed physis are described as transitional fractures. The distal tibia is one of the most common locations for transitional fractures second only to the distal radius. Aim of this retrospective study was to evaluate the clinical and radiological results after surgical treatment of transitional fractures of the distal tibia. PATIENTS AND METHODS: From May 2003 to March 2009 24 children (median age 14 years) received surgical treatment for transitional fractures of the distal tibia. 89% (21/24) of patients were followed up after 27.5 (range 6 to 72) months to assess functional out come (using the AO Foot and Ankle Score). RESULTS: Nine girls and 15 boys were included in the study with the girls being younger on average (12.4 ± 0.9 vs. 14.3 ± 1.1 years, p = 0.00013). Two-plane fractures were present in 4 cases, 15 and 5 children sustained tri-plane I and II fractures, respectively. Median preoperative fracture displacement was measured at 4 mm (range 3 to 11 mm). Traumatic supination of the ankle joint during sports activities was the predominant injury mechanism (18/24 cases) followed by bicycle or motorbike accidents (6/24). A satisfactory reduction (1 mm or less) was achieved in all but one patient. In this case revision surgery was necessary to restore anatomical reduction. No perioperative complications occurred in the remaining 23 cases. Metal implants were removed upon fracture consolidation after 8.2 ± 6.7 months. At the time of follow-up none of the children were impaired in activities of daily living and there were no restrictions in sporting activity. All patients sco- red good or excellent results on the AO Foot and Ankle Score. DISCUSSION: Surgical stabilization can be recommended as a safe and effective treatment strategy in displaced transitional fractures of the distal tibia and will lead to good or excellent mid term results.

Surgical treatment of supracondylar humerus fractures in children.

PURPOSE OF THE STUDY: Surgical techniques for the treatment of supracondylar fractures in children are repeatedly the subject of discussion. The aim of the present study was to compare experience with the technique of crossed Kirschner wires at our own hospital with current literature. PATIENTS AND METHODS: In the period from 2000-2006 a total of 86 children aged 1.7 to 12.7 years were treated by means of crossed K-wire osteosynthesis. Follow up was conducted at an average of 32 months. Outcomes were evaluated based on von Laer's criteria. RESULTS: Reported complications were migration of the K-wires in 7% of cases and secondary dislocation and re-operation in 4% of cases. Lesion of the radial nerve was diagnosed postoperatively in two cases. Hospital stay was 1.5 days on average. Postoperative immobilization in an upper arm splint and implant removal after 6 weeks on average. 57% of the children received physiotherapy during the course of treatment. Slight varization was found in 11% of children and an unsatisfactory range of motion in 13%. Satisfactory outcomes were recorded for 83% of patients. CONCLUSION: K-wire osteosynthesis is associated with a low complication rate and continues to be a safe standard procedure for the stabilization of supracondylar humerus fractures. Key words: supracondylar humerus fracture, Kirschner wires, paediatric fractures.

Comparison of the Radiation Dose from Cone Beam Computed Tomography and Multidetector Computed Tomography in Examinations of the Hand.

PURPOSE: Comparison of radiation dose of cone beam computed tomography (CBCT) and multidetector computed tomography (MDCT) in examinations of the hand. MATERIALS AND METHODS: Dose calculations were carried out by means of Monte Carlo simulations in MDCT and CBCT. A corpse hand was examined in a 320-row MDCT scanner and a dedicated extremities CBCT scanner with standard protocols and multiple low-dose protocols. The image quality of the examinations was evaluated by 5 investigators using a Likert scale from 1 (very good) to 5 (very poor) regarding depiction of cortical bone, cancellous bone, joint surfaces, soft tissues and artifacts. For a sum of ratings of all structures < 50 a good overall image quality was expected. The studies with at least good overall image quality were compared with respect to the dose. RESULTS: The dose of the standard examination was 13.21 (12.96 to 13.46 CI) mGy in MDCT and 7.15 (6.99 to 7.30 CI) mGy in CBCT. The lowest dose in a study with good overall image quality was 4.54 (4.43 to 4.64 CI) mGy in MDCT and 5.72 (5.59 to 5.85 CI) mGy in CBCT. CONCLUSION: Although the dose of the standard protocols in the CBCT is lower than in the MDCT, the MDCT can realize a good overall image quality at a lower dose than the CBCT. Dose optimization of CT examination protocols for the hand is useful in both modalities, the MDCT has an even greater potential for optimization. KEY POINTS: • Low dose examinations of the hand are feasible in CBCT and MDCT.• In default settings CBCT has a lower dose than MDCT.• MDCT enables a good image quality at a lower dose than CBCT. Citation Format: • Neubauer J, Neubauer C, Gerstmair A et al. Comparison of the Radiation Dose from Cone Beam Computed Tomography and Multidetector Computed Tomography in Examinations of the Hand. Fortschr Röntgenstr 2016; 188: 488 - 493.

Biomechanical evaluation of two innovative locking implants for comminuted olecranon fractures under high-cycle loading conditions.

INTRODUCTION: The relatively high complication rate after fixation of olecranon fractures has led to an increasing application of anatomically pre-contoured locking plate systems. The purpose of the present study was to conduct a biomechanical comparison of olecranon osteosyntheses by applying the Olecranon VA-LCP and the 3.5mm LCP Hook Plate (LCP, locking compression plate) to an unstable fracture model under high-cycle loading conditions. METHODS: After creating an unstable fracture (Schatzker type B), osteosynthesis was performed on eight pairs of fresh-frozen cadaveric ulnae by application of either the Olecranon VA-LCP (Synthes, Solothurn, Switzerland) or the 3.5mm LCP Hook Plate (Synthes, Solothurn, Switzerland). Loading (50,000 alternating loads, cyclic and sinusoidal 10-300 N) was conducted by application of tensile load with the elbow in 90° flexion to simulate the tensile strength of the triceps brachii. For statistical analysis, angular displacement in the region of the humeral trochlea was taken as a measure of olecranon dislocation. RESULTS: In Group 1 (Olecranon VA-LCP), a median angular displacement of 0.36° (minimum 0.10°; maximum 0.80°) was observed after 500 alternating loads. In Group 2 (3.5-mm LCP Hook Plate), the medial displacement was 0.80° (minimum 0.13°; maximum 2.72°). The difference was nonsignificant (p = 0.128). The mean value for angular displacement in Group 1 after 50,000 cycles was 0.80° (minimum 0.31°; maximum 1.99°), whereas in Group 2 a mean angular displacement of 2.02° (minimum 0.71°; maximum 6.40°) was recorded. The difference was statistically significant (p = 0.017). In Group 2, implant failure in the form of proximal plate pullout occurred in one construct after 756 cycles. CONCLUSION: A significantly higher biomechanical stability can be achieved in the fixation of unstable olecranon fractures by application of the Olecranon VA-LCP rather than the 3.5mm LCP Hook Plate.

Sonographical detection of free gas in the peritoneal cavity.

Using suitable examination technique free gas in the peritoneal cavity can be as reliably detected by sonography as by x-ray. The identical sensitivity of both methods is experimentally proved up to a gas-volume of 1 ml.

Ivermectin quantitation with an abamectin internal standard.

The potent antiparasitic ivermectin is detected at low concentrations (ng/g) in liver and muscle tissue by liquid chromatography after conversion to a fluorescent derivative with 1-methylimidazole and trifluoroacetic anhydride. This acetylation reaction can be compromised by residual water that leads to decreased yields. Yields of derivatives of ivermectin and abamectin, a related avermectin, are identical under all circumstances tested. Use of abamectin as an internal standard eliminates derivative yield as a source of analytical variation.

Solid-phase extraction cleanup for ivermectin in liver tissue.

Extraction of liver tissue with organic solvent produces coextractants with compounds of interest. The solid-phase extraction (SPE) cleanup of liver tissue developed for ivermectin removes nonpolar coextractants. Liver extract that has been reduced to dryness is reconstituted in 0.5 mL acetonitrile. The mixture is passed through 0.1 g C18 SPE column, and the eluate is collected. The column is eluted further with 2 mL acetonitrile. Combined eluates are derivatized with 1-methylimidazole and trifluoroacetic anhydride, and the ivermectin derivative is determined by liquid chromatography with fluorescence detection.

Minimally invasive stabilization of distal humerus fractures: a pilot study with biomechanical evaluation.

BACKGROUND: Fracture of the distal humerus is a fairly rare injury and makes high demands on the treating surgeon. Prerequisites for a good outcome are anatomical reconstruction and osteosynthesis stable enough for exercises. A method permitting early restoration of function is especially important for patients with osteoporosis. The extensive surgical approach necessary for open reduction is associated with a high number of wound healing disorders and infections with a frequency of 11% being reported in the literature. Although open reduction and internal fixation in double-plating technique is unavoidable for complex intraarticular fractures, an alternative, minimally invasive and, consequently, tissue-preserving procedure is desirable for simpler fractures. OBJECTVE: To investigate this issue further an angular stable nail system developed for the distal radius was implanted as a stabilizer and the construct tested biomechanically as part of a feasibility study. METHODS: Distal humerus fractures were stabilized by insertion of a distal radius nail, namely, the Targon DR (Aesculap, Tuttlingen) and a K-wire. To test the hypothesis six cadaveric bones fixed in formalin were tested biomechanically for displacement, implant failure, and stiffness. Displacement was determined by means of an ultrasound-based system. RESULTS: An average displacement of 1.6 mm ± 0.7 was recorded at a maximum compression force of 100 N in extension and an average displacement of 1.4 mm ± 0.9 in flexion. Implant failure was not observed for any of the constructs. CONCLUSIONS: The study presented here permits the conclusion that a minimally invasive procedure is possible at the distal humerus and does ensure adequate stability. Although the nail was not specifically designed for the humerus, current findings form the basis for a promising approach that will be pursued further after modification of the nail design.

[Fractures of the humerus head]. / Frakturen des Humeruskopfes.

Fractures of the proximal humerus are commonly seen especially in the elderly population. High-energy trauma in young people can be distinguished from low-energy trauma in the elderly resulting from falls of a low height which are typically characterized by osteoporosis. A precise analysis of fractures is essential for a good understanding of the fracture and an individual therapy for which the LEGO-Codman classification provided by Hertel is recommended. Nonsurgical therapy is commonly performed and widely accepted not only for simple fractures. For osteosynthesis angular stable implants became the gold standard but are frequently associated with a high rate of complications some of which can be lowered by an improved surgical technique. Even today varus dislocated fractures are challenging, especially in combination with destruction of the medial column. In those cases where stable osteosynthesis can no longer be achieved arthroplasty is indicated. The clinical results of anatomic fracture arthroplasty are strongly related with correct ingrowth of the tuberosities. Reverse fracture arthroplasty may be considered but indications should be interpreted with caution and preferably used in patients older than 75 years.

[Therapy of humeral shaft fractures]. / Therapie der Humerusschaftfraktur.

Fractures of the humeral shaft are less frequent than those of the proximal humerus. The formerly recommended treatment of humeral shaft fractures was conservative according to Böhler. This still remains an adequate concept of treatment but according to a change in the technical possibilities and the demands of patients and physicians on fast restoration of function and low pain, there is a trend towards surgical stabilization of humeral shaft fractures. The implant of choice is discussed controversially and consists of various types of nails versus plating. The technique of nailing is antegrade or retrograde and depends on the localization of the fracture. In our opinion good indications for plating are combined fractures of the proximal humerus and the shaft as well as very distal humeral shaft fractures. A primary lesion of the radial nerve is no imperative indication for exploration and different studies have shown the same results for exploration after 2 or 3 months if there is no spontaneous remission.

[Monteggia lesions in children--a clinical trial]. / Monteggia-Verletzungen im Kindesalter.

BACKGROUND: The Monteggia lesion is a rare injury of the elbow in children. This lesion is defined as a shaft fracture of the ulna combined with a luxation of the radial head. The primary problem in this injury is the proper diagnosis because the misalignment of the radial head is often missed. The purpose of this study was to retrospectively analyse the results after Monteggia lesions in children. PATIENTS AND METHODS: Ten children between two and nine years of age (six boys and four girls) were clinically assessed using the Morrey score. They were treated in our department between December 1999 and October 2004. RESULTS: The Morrey score after 54 months (min.: 26/max.: 84) had a median value of 100 points with 100 being the maximum (min.: 95/max.: 100). We found two complications, a combined lesion of the radial and ulnar nerves which completely recovered after six months. In one case a k-wire dislocated, which was removed earlier. DISCUSSION: If the Monteggia lesion in children is correctly diagnosed and treated early enough, only good and very good results may be expected. After delayed diagnosis and treatment, the clinical results are not as good or even very poor.

Stabilisation of articular fractures of the distal humerus: early experience with a novel perpendicular plate system.

INTRODUCTION: The treatment of fractures of the distal humerus is difficult and involves the risk of bad functional results, particularly with articular fractures or impaired bone quality. Anatomical reconstruction and stable fixation allowing early mobilisation of the elbow are the basic prerequisites for good clinical outcomes. The aim of our study was to evaluate whether the Distal Humerus Plate (DHP, Synthes), a novel, perpendicular, fixed-angle plate system, fulfils the requirements for this treatment goal. METHODS: From 2004 to 2007, 46 consecutive patients (19 men and 21 women; mean age of 60.5 years) underwent open reduction and internal fixation with the new DHP system. Six patients were lost to follow up. The remaining 40 patients were followed up for 11 months (range 4-24 months). Follow up involved assessment of functional outcome using the Mayo Elbow Performance Score (MEPS) and Liverpool Elbow Score (LES), reduction results and complication rates. Subgroup analyses involved comparisons of younger (<60 years) to elderly (> or =60 years) patients and type C3 injuries versus other fracture patterns. RESULTS: Only six cases received primary internal fixation, whilst 31 patients were temporarily stabilised by either external fixation or cast before ORIF could be performed. Three patients were treated for implant failure (systems other than DHP) after surgery in other hospitals. The mean time from injury to internal fixation was 7 days. Open fractures were present in 10 cases. Olecranon osteotomy was required for reduction in 35 cases. Mean operation time was 215 min. 'Good' or 'excellent' results were observed in 29/40 patients. Median MEPS and LES were 84 and 8.1 points, respectively. Mean ROM was 100 degrees. We found no significant differences in the subgroup analyses; however, there was a tendency towards better functional results in younger patients and injuries without comminution of the articular surface. Complications comprised two superficial wound infections, two cases of heterotopic ossification, one case of delayed union and five cases of transient ulnar neuropathy. Implant failure was observed twice in one patient. CONCLUSION: Open reduction and internal fixation with the DHP system provides reliable, stable fixation allowing early functional mobilisation of the elbow joint, even in complex fractures and impaired bone quality, resulting in good outcomes for the majority of patients. The complication rate reported here is comparable to that of other implants, but the low number of implant failures is promising and warrants further investigation.

[What is the value of the whole body spiral CT in the primary radiological imaging of severely injured children?]. / Welchen Stellenwert hat das Ganzkörper-Spiral-CT in der Primärdiagnostik polytraumatisierter Kinder?

AIM: Whole body spiral CT scans have become a routine method in the radiological imaging of severely injured patients in emergency rooms of an increasing number of hospitals. The routine use of CT scans is, however, still discussed controversially, especially with regard to its use in children. This is mainly due to the reportedly higher level of exposure to radiation of CT scans as compared to plain radiographs. The aim of the present study was to compare the dose of exposure to radiation of a whole body CT scan to that of a plain radiograph protocol in an animal model for severely injured children. MATERIAL AND METHODS: We chose 3 female pigs of different weights to serve as a model for children at different ages. 4 film radiation dosimeters (positioned on the eye, under the breast, paravertebrally on the thoracic spine and in the small pelvis, respectively) were implanted into every pig for each examination. Plain radiographs of the chest and the pelvis in one plane and of the skull and the complete spine in two planes were performed. The CT scan included skull, cervical spine and the whole body from the thorax to pelvis. RESULTS: The radiation dose of CT scans was 7 times higher as compared to the X-ray protocol, but the performance of CT scans was faster (8 vs. 18 min). The radiation dose of the whole body CT scan was at about 15 mSv. CONCLUSION: Based on our data and a review of the literature we will use whole body spiral CT scans as the preferred method in the primary radiological imaging of severely injured patients. In our opinion, the evident benefit of a reduced time of imaging in combination with superior image information outweighs the higher level of exposure to radiation.

[Halo-fixator vest--indications and complications]. / Halo-Fixateur - Indikationen und Komplikationen.

Over the period between 06/00 and 03/03, 41 patients with different injuries of the upper cervical spine were treated by a halo fixator and were statistically recorded. The collective showed different injury patterns, 2 fractures of occiput condyles (5%), 3 Jefferson fractures (7%), 1 combined injury of the odontoid process and an atlas fracture (2%), 32 odontoid fractures (78%), 2 hanged-man-fractures Typ Effendi II (5%) and one case of pathologic fractures from the 2. to the 4. cervical vertebral body based on a plasmocytoma (2%). 31 of 41 patients could be examined for a follow up; 40 complete medical histories were well documented and could be analysed. As complications we had screw loosening in 6 cases (15%), a complete tear out of screws in 2 cases (5%). One patient took the halo away by himself two times, so after the second time surgical stabilisation was performed (2,5%). One case of intracranial penetration of a screw happened after the patient fell down in an accident with the halo (2,5%). Infection of the screw pins appeared in 4 cases (10%) and we had 2 cases of skin necrosis (5%). A second reduction after redisplacement was necessary in 8 cases (20%). 23 patients suffered from pain at the insertion of the screws (75%) and 18 patients complained of pressure in the head (58%). On the question of the comfort of this kind of therapy answered 18 patients with "intolerable" (58%), 10 patients with middle (32%) and 3 patients with tolerable (10%). Despite of the large number of different complications and the miscomfort of a halo fixator we think that there are still indications for treatment of special injuries of the upper cervical spine with a halo fixator. One important aspect is the lack of adequate alternatives even with regard to the biomechanical stability.

[Congenital radial head dislocation on both sides]. / Kongenitale Radiusköpfchenluxation beidseits.

Both traumatic and congenital dislocation of the radial head are very rare in childhood. It can sometimes be difficult to tell them apart in practice. In this paper therefore, we present one case and discuss the various aspects of both conditions with reference to the available literature. Traumatic dislocation of the radial head is generally easily reduced without open surgery, and an open procedure is virtually never indicated in a patient who is still growing. In contrast, specific treatment of congenital radial head dislocation is not necessary because most patients are free of pain.

[Intertrochanteric femoral fractures in children]. / Intertrochantäre Femurfrakturen im Kindesalter.

Based on two cases and a review of the literature, we describe a rare injury in childhood, intertrochanteric femoral fracture. Because of the insertion and traction of muscles at the proximal femur, conservative treatment is difficult. The hip muscles pull the proximal fragment into flexion, abduction and external rotation. In our opinion, surgical stabilization is the therapy of choice. We use an angular stable, locking compression plate for the stabilization of these fractures. Postoperatively, mobilization with full weight bearing is possible.