Epidemiology and socioeconomic consequences of work-related pelvic and acetabular fractures recorded in the German Social Accident Insurance.

INTRODUCTION: Pelvic and acetabular fractures can result from work-related accidents and frequently require lengthy medical treatments. Consequently, high medical costs as well as delayed or absent return to work can be the consequence. Therefore, we aimed to study the socioeconomic consequences of work-related pelvic and acetabular fractures. MATERIALS AND METHODS: This retrospective study investigated work-related pelvic and acetabular fractures recorded in the German Social Accident Insurance in 2011 and 2017, in terms of age, sex, type of accident, duration of incapacity to work, reductions in earning capacity, costs for outpatient and inpatient treatment and costs for pension and severance pay. RESULTS: Among a total of 606 injuries in 2011 and 619 injuries in 2017, male patients and patients between 40 and 65 years were predominantly affected. Acetabular fractures caused higher rates of long absence from work of 6-12 months (2011: 24.7% vs. 9.5-16.9%; 2017: 26.1% vs. 6.1-11.0%) and >12 months (2011: 15.8% vs. 9.8-10.2%; 2017: 13.3% vs. 1.9-8.2%) as well as more cases with a reduction in earning capacity of at least 20% (2011: 61 vs. ≤27 cases; 2017: 39 vs. ≤12 cases) compared to pelvic ring fractures. The total costs for pelvic ring and acetabular fractures in the German social accident insurances amounted € 18,726,630 and € 9637,189 in the periods 2011-2020 and 2017-2020, respectively. The average costs per case for treatment and rehabilitation until 2020 was € 19,079 for injuries from 2011 and € 13,629 for injuries from 2017. Acetabular fractures were found to be the most cost-intensive injuries compared to anterior, posterior or complex pelvic ring fractures. CONCLUSIONS: Work-related pelvic and especially acetabular fractures have a considerable socioeconomic impact in the German Social Accident Insurance. Measures to prevent work-related accidents and to improve treatment of pelvic injuries can help to reduce their socioeconomic burden.

A Register Analysis after Tibial Plateau Fracture in Statutory Accident Insurance. / Ergebnisse und Kosten nach Tibiakopffraktur in der gesetzlichen Unfallversicherung ­ eine Registeranalyse.

OBJECTIVE: To analyse the results after tibial plateau fractures with a focus on socioeconomic consequences. METHODS: On the basis of the data from the rehabilitation documentation of the German Statutory Accident Insurance (DGUV) on tibial plateau fractures (Code 83), a retrospective anonymised evaluation of the injuries which occurred in 2010 and 2016 was carried out. The registry data allowed subdivision into 3 groups: Medial, lateral and bicondylar tibial plateau fractures. The data have been analysed with regard to the following parameters: age, gender, treatment, time of return to work (AU), costs per case, total costs, workers compensation (MdE) and total payments. RESULTS: The analysis includes 1046 isolated tibial plateau fractures for 2010 and 1072 for 2016. In 2016, 798 fractures could be assigned to the medial, lateral or bicondylar fracture groups. In 551 cases, both condyles were involved. In another 221 cases, the lateral plateau and in 26 the medial plateau was injured. There were 476 (59.7%) men and 322 (40.4%) women. The mean age was 43.4 (SD ± 16.7) years with a peak of 180 cases in the 55-60 year subgroup and 98 aged 15-20 years. The mean age of the cases with isolated lateral plateau involvement was 48.1 (SD ± 13.8) and was 47.5 (SD ± 16.6) in those with medial plateau fractures and 41.4 (SD ± 17.2) years in the subgroup with bicondylar patterns. The mean time of return to work was 39.4 (SD ± 25.3) weeks for the bicondylar tibial plateau fractures, 28.1 (SD ± 27.2) weeks for the medial and 24.5 (SD ± 22.8) weeks for the lateral groups. For the 2016 group, the mean costs were 5212 € for outpatient, 10358 € for inpatient and 7622 € for rehab costs per case (total costs over three years of 4247443 € for outpatient and 7506508 € for acute inpatient treatment). The highest costs per case were caused by the inpatient acute treatment of bicondylar tibial plateau fractures, at a mean of 22292 €. 17.6% of the 2016 casualty group resulted in compensation of at least 20%. The treatment costs for the 2010 group over 9 years (2010-2019) amounted to 4190855 € for outpatient treatments and € 9565313 for inpatient treatments. In addition, compensations of 8632448 € and lump-sum payments of 483289 € were paid from 2010 to 2019. Over a period of 9 years, 456 (66%) of 692 patients needed another in patient follow-up treatment. A total of 51% (n = 353) needed these treatments within the first year. CONCLUSION: Tibial plateau fractures, in particular bicondylar tibial plateau fractures, show long-term, cost-intensive healing processes with reduced occupational capacity. Tibial plateau fractures are of economic importance in the statutory accident insurance in the long term. Preventive measures, optimal care and rehabilitation are therefore essential, together with innovative research to improve clinical outcomes.

Biomechanical analysis of fixation methods in acetabular fractures: a systematic review of test setups.

PURPOSE: Optimal anatomical reduction and stable fixation of acetabular fractures are important in avoiding secondary dislocation and osteoarthritis. Biomechanical studies of treatment options of acetabular fractures aim to evaluate the biomechanical properties of different fixation methods. As the setup of the biomechanical test can influence the experimental results, this review aimed to analyze the characteristics, comparability and clinical implications of studies on biomechanical test setups and finite element analyses in the fixation of acetabular fractures. METHODS: A systematic literature research was conducted according to the PRISMA guidelines, using the PubMed/MEDLINE and Web of Science databases. 44 studies conducting biomechanical analyses of fixation of acetabular fractures were identified, which met the predefined inclusion and exclusion criteria and which were published in English between 2000 and April 16, 2021. The studies were analyzed with respect to distinct parameters, including fracture type, material of pelvis model, investigated fixation construct, loading direction, loading protocol, maximum loading force, outcome parameter and measurement method. RESULTS: In summary, there was no standardized test setup within the studies on fixation constructs for acetabular fractures. It is therefore difficult to compare the studies directly, as they employ a variety of different test parameters. Furthermore, the clinical implications of the biomechanical studies should be scrutinized, since several test parameters were not based on observations of the human physiology. CONCLUSION: The limited comparability and restricted clinical implications should be kept in mind when interpreting the results of biomechanical studies and when designing test setups to evaluate fixation methods for acetabular fractures.

Evaluation of a syndromic panel polymerase chain reaction (spPCR) assay for the diagnosis of device-associated bone and joint infections (BJI).

OBJECTIVE: Pathogen detection is crucial for diagnosis and targeted therapy in implant-associated bone and joint infections (BJI). Culture-based microbiology regularly fails to identify causative pathogens. This study evaluated the diagnostic accuracy and clinical usefulness of a syndromic panel polymerase chain reaction (spPCR) assay targeting common BJI pathogens in tissue specimens from patients with implant-associated BJI. METHODS: Results obtained by spPCR assay and a 16S rDNA PCR were compared with results obtained from a standard of care (SOC) culture-based diagnostics, serving as a gold standard. In total, 126 specimens obtained from 73 patients were analyzed. RESULTS: The spPCR assay correctly identified 33/40 culture-positive samples (82.5 %) and was positive in 9/86 (10.5 %) culture-negative samples, resulting in an overall sensitivity of 84.6 % (95% confidence interval [CI] 68.79-93.59%) and specificity of 89.35% (95% CI 80.6-94.81%). The spPCR was more sensitive compared with the 16S rDNA PCR (37.5%). The spPCR identified pathogens in 7/51 (13.7%) SOC-negative patients. Re-evaluation of spPCR results in clinical context suggested their clinical significance. CONCLUSION: An spPCR assay targeting common pathogens causing implant-associated BJI may help to identify causative agents in culture-negative cases. As false-negative results are possible, spPCR assays appear as an add-on approach for pathogen detection in implant-associated BJI.

Stresses and deformations of an osteosynthesis plate in a lateral tibia plateau fracture.

This study has the aim to investigate the strain and stress in an anterolateral locking plate applied for the fixation of a lateral split fracture. To simulate a complex fracture situation, three segments were separated. With a FEM analysis, representative places for strain and stress measurement were determined. A locked osteosynthesis plate was instrumented with strain gauges and tested on a fractured and a non-fractured Saw Bone model. To simulate different loading situations, four different points of force application, from the center of the condyles to a 15 mm posterior position, were used with a medial-lateral load distribution of 60:40. The simulations as well as the biomechanical tests demonstrated that two deformations dominate the load on the plate: a bending into posterior direction and a bulging of the plate head. Shifting the point of application to the posterior direction resulted in increasing maximum stress, from 1.16 to 6.32 MPa (FEM analysis) and from 3.04 to 7.00 MPa (biomechanical study), respectively. Furthermore, the comparison of the non-fractured and fractured models showed an increase in maximum stress by the factor 2.06-2.2 (biomechanical investigation) and 1.5-3.3 (FEM analysis), respectively.

Radiation Dose to the Eye Lens Through Radiological Imaging Procedures at the Surgical Workplace During Trauma Surgery.

Background: Due to the drastic reduction of the eye lens dose limit from 150 mSv per year to 20 mSv per year since 2018, the prospective investigation of the estimated dose of the eye lens by radiological imaging procedures at the surgical site during trauma surgery in the daily work process was carried out. This was also necessary because, as experience shows, with changes in surgical techniques, there are also changes in the use of radiological procedures, and thus an up-to-date inventory can provide valuable information for the assessment of occupationally induced radiation exposure of surgical personnel under the current conditions. Methods: The eye lens radiation exposure was measured over three months for five trauma surgeons, four hand surgeons and four surgical assistants with personalized LPS-TLD-TD 07 partial body dosimeters Hp (0.07). A reference dosimeter was deposited at the surgery changing room. The dosimeters were sent to the LPS (Landesanstalt für Personendosimetrie und Strahlenschutzausbildung) measuring institute (National Institute for Personal Dosimetry and Radiation Protection Training, Berlin) for evaluation after 3 months. The duration of the operation, occupation (assistant, surgeon, etc.), type of surgery (procedure, diagnosis), designation of the X-ray unit, total duration of radiation exposure per operation and dose area product per operation were recorded. Results: Both the evaluation of the dosimeters by the trauma surgeons and the evaluation of the dosimeters by the hand surgeons and the surgical assistants revealed no significant radiation exposure of the eye lens in comparison to the respective measured reference dosimeters. Conclusions: Despite the drastic reduction of the eye lens dose limit from 150 mSv per year to 20 mSv per year, the limit for orthopedic, trauma and hand surgery operations is well below the limit in this setting.

Low-pressure micro-mechanical re-adaptation device sustainably and effectively improves locomotor recovery from complete spinal cord injury.

Traumatic spinal cord injuries result in impairment or even complete loss of motor, sensory and autonomic functions. Recovery after complete spinal cord injury is very limited even in animal models receiving elaborate combinatorial treatments. Recently, we described an implantable microsystem (microconnector) for low-pressure re-adaption of severed spinal stumps in rat. Here we investigate the long-term structural and functional outcome following microconnector implantation after complete spinal cord transection. Re-adaptation of spinal stumps supports formation of a tissue bridge, glial and vascular cell invasion, motor axon regeneration and myelination, resulting in partial recovery of motor-evoked potentials and a thus far unmet improvement of locomotor behaviour. The recovery lasts for at least 5 months. Despite a late partial decline, motor recovery remains significantly superior to controls. Our findings demonstrate that microsystem technology can foster long-lasting functional improvement after complete spinal injury, providing a new and effective tool for combinatorial therapies.

Biomechanical comparison of a multidirectional locking plate and conventional plates for the osteosynthesis of mandibular angle fractures-A preliminary study.

PURPOSE: The objective of surgical fracture management is to reduce and fixate fractures accurately and rapidly. Two osteosynthesis plates are usually used in the treatment of mandibular angle fractures to enhance torsional stiffness. We conducted biomechanical tests under static and cyclic loading to assess whether a single locking plate is as efficacious as two conventional plates in the osteosynthesis of mandibular angle fractures. MATERIALS AND METHODS: Fracture gaps were created in synthetic mandible replicas. After pretests, the stiffness of a single locking plate and different types of non-locking, two-plate systems was assessed and compared under static and cyclic loading. The plates were subjected to a maximum static load of 750 N and underwent cyclic loading at a constant force of 400 N during a maximum of 500,000 cycles. RESULTS: No plastic deformation occurred in the static tests. Both types of osteosynthesis showed high static stability. The locking plate was significantly stiffer than the non-locking plates (p = 0.0079). Cyclic loading tests did not reveal any significant differences. CONCLUSION: Within the limitations of this preliminary study, a single locking miniplate appears to be as efficacious in biomechanical tests as non-locking, two-plate systems for the management of mandibular angle fractures.

Air Medical Evacuations From the German North Sea Wind Farm Bard Offshore 1: Traumatic Injuries, Acute Diseases, and Rescue Process Times (2011-2013).

OBJECTIVE: Our purpose was 2-fold: 1) to show emergency-related traumatic injury and acute disease patterns and 2) to evaluate air rescue process times in a remotely located German offshore wind farm. Optimally, this will support methodologies to reduce offshore help time (time from the incoming emergency call until offshore arrival of the helicopter). METHODS: The type and severity of traumatic injuries and acute diseases were retrospectively analyzed for 39 air medevacs from August 2011 to December 2013, and the process times of air rescue missions were evaluated in detail. RESULTS: Forty-nine percent of the medevacs were related to traumatic injuries, whereas 41% were associated with acute diseases and 10% remained unclear. Cardiovascular and gastrointestinal disorders accounted for 90% of internal medical cases. About 69% of the trauma was related to contusions, lacerations, and cuts. The main body regions injured were limbs (∼59%) and head (∼32%). The total rescue time until arrival at the destination facility averaged 175.3 minutes (standard deviation = 54.4 minutes). The mean helicopter offshore arrival time was 106.9 minutes (standard deviation = 57.4 minutes) after the incoming emergency call. In 64% of the medevacs, the helicopter arrived on scene within a help time of 90 minutes. CONCLUSION: A reduction of help time (≤ 60 minutes) for time-critical severe trauma and acute diseases may be anticipated through rapid and focused medical and logistic decision-making processes by the onshore dispatch center combined with professional, qualified, and well-trained flight and rescue personnel.

Experimental Strategies to Bridge Large Tissue Gaps in the Injured Spinal Cord after Acute and Chronic Lesion.

After a spinal cord injury (SCI) a scar forms in the lesion core which hinders axonal regeneration. Bridging the site of injury after an insult to the spinal cord, tumor resections, or tissue defects resulting from traumatic accidents can aid in facilitating general tissue repair as well as regenerative growth of nerve fibers into and beyond the affected area. Two experimental treatment strategies are presented: (1) implantation of a novel microconnector device into an acutely and completely transected thoracic rat spinal cord to readapt severed spinal cord tissue stumps, and (2) polyethylene glycol filling of the SCI site in chronically lesioned rats after scar resection. The chronic spinal cord lesion in this model is a complete spinal cord transection which was inflicted 5 weeks before treatment. Both methods have recently achieved very promising outcomes and promoted axonal regrowth, beneficial cellular invasion and functional improvements in rodent models of spinal cord injury. The mechanical microconnector system (mMS) is a multi-channel system composed of polymethylmethacrylate (PMMA) with an outlet tubing system to apply negative pressure to the mMS lumen thus pulling the spinal cord stumps into the honeycomb-structured holes. After its implantation into the 1 mm tissue gap the tissue is sucked into the device. Furthermore, the inner walls of the mMS are microstructured for better tissue adhesion. In the case of the chronic spinal cord injury approach, spinal cord tissue - including the scar-filled lesion area - is resected over an area of 4 mm in length. After the microsurgical scar resection the resulting cavity is filled with polyethylene glycol (PEG 600) which was found to provide an excellent substratum for cellular invasion, revascularization, axonal regeneration and even compact remyelination in vivo.

Accuracy of a hexapod parallel robot kinematics based external fixator.

BACKGROUND: Different hexapod-based external fixators are increasingly used to treat bone deformities and fractures. Accuracy has not been measured sufficiently for all models. METHODS: An infrared tracking system was applied to measure positioning maneuvers with a motorized Precision Hexapod® fixator, detecting three-dimensional positions of reflective balls mounted in an L-arrangement on the fixator, simulating bone directions. By omitting one dimension of the coordinates, projections were simulated as if measured on standard radiographs. Accuracy was calculated as the absolute difference between targeted and measured positioning values. RESULTS: In 149 positioning maneuvers, the median values for positioning accuracy of translations and rotations (torsions/angulations) were below 0.3 mm and 0.2° with quartiles ranging from -0.5 mm to 0.5 mm and -1.0° to 0.9°, respectively. CONCLUSIONS: The experimental setup was found to be precise and reliable. It can be applied to compare different hexapod-based fixators. Accuracy of the investigated hexapod system was high.

A mechanical microconnector system for restoration of tissue continuity and long-term drug application into the injured spinal cord.

Complete transection of the spinal cord leaves a gap of several mm which fills with fibrous scar tissue. Several approaches in rodent models have used tubes, foams, matrices or tissue implants to bridge this gap. Here, we describe a mechanical microconnector system (mMS) to re-adjust the retracted spinal cord stumps. The mMS is a multi-channel system of polymethylmethacrylate (PMMA), designed to fit into the spinal cord tissue gap after transection, with an outlet tubing system to apply negative pressure to the mMS thus sucking the spinal cord stumps into the honeycomb-structured holes. The stumps adhere to the microstructure of the mMS walls and remain in the mMS after removal of the vacuum. We show that the mMS preserves tissue integrity and allows axonal regrowth at 2, 5 and 19 weeks post lesion with no adverse tissue effects like in-bleeding or cyst formation. Preliminary assessment of locomotor function in the open field suggested beneficial effects of the mMS. Additional inner micro-channels enable local substance delivery into the lesion center via an attached osmotic minipump. We suggest that the mMS is a suitable device to adapt and stabilize the injured spinal cord after surgical resection of scar tissue (e.g., for chronic patients) or traumatic injuries with large tissue and bone damages.

Is the Wave Plate Still a Salvage Procedure for Femoral Non-union? Results of 75 Cases Treated with a Locked Wave Plate.

OBJECTIVE: To analyse the results of the treatment of aseptic femoral non-unions using a singular locked implant. DESIGN: Consecutive case series. SETTING: A level-1 trauma center with a high number of specialist referrals. PATIENTS: The study is based on a consecutive series of patients with prospective data evaluation. From 1993 to 2003, 75 patients were treated with a wave plate. All patients had persistent non-union of the femoral shaft without clinical or laboratory signs of infection and previous unsuccessful attempts to treat the non-union. INTERVENTION: The method of treatment was standardized and included a lateral approach, cancellous bone hip grafting, osteosynthesis with a wave-shaped plate (PPF) and polyaxial locking screws as well as the application of a gentamicin-PMMA chain. MAIN OUTCOME MEASUREMENTS: Time to achieve union, rate of implant failure and number of remaining nonunions after treatment. A total of 75 patients had full follow-up and were included in the study. RESULTS: The union of the fracture was found in 64 patients after the initial procedure. In eight cases a second procedure was performed to achieve union in the form of a second bone graft because of a delay in callus formation. The mean time to union was 7.3 months with a range from 3 to 19 months. The implant failed in three cases accounting for 4% of the total. CONCLUSION: The locked wave plate offers a further reliable treatment for complex aseptic femoral non-unions.

Severe Fracture of the Tibial Pilon: Results with a Multidirectional Self-locking Osteosynthesis Plate Utilizing a Two-stage Procedure.

The objective of this study is to determine the treatment result of severe fractures of the tibial pilon using a two-stage treatment plan with a singular implant type. The setting is a level 1 trauma centre, the design a consecutive series of patients with a retrospective data evaluation. Due to anatomical circumstances, soft-tissue treatment is extremely important for fractures of the tibial plafond. After promising results reported about a two-staged treatment plan with external fixation and secondary internal fixation, we incorporated this method in our treatment protocol. This consisted in a second stage of internal fixation with a specifically developed locked pilon plate with multi-directional applicable screws. Between March 2000 and February 2005, 42 patients with high-energy fractures of the tibial plafond were treated using a two-staged treatment plan: firstly the fracture was stabilized with an external fixator immobilizing the ankle joint. Secondly, after stabilization of the soft-tissue situation (mean 9.2 days) open reduction and internal fixation with a locked-screw plate was performed. Complications experienced included three cases of superficial wound necrosis, in two cases a deep vein thrombosis occurred. All fractures healed but two patients needed an early bone graft because of insufficient bony consolidation. At follow-up, six Patients had no deficit in the range of movement of the ankle compared with the unaffected side, 19 patients experienced a deficit of movement of less then one third compared to the opposite side. In 27 cases no or only mild posttraumatic arthritis of the ankle occurred. There was no secondary loss of reduction or need for arthrodesis. The mean AOFAS score was 73.4 (52-97). A two-stage treatment plan in fractures of the distal lower limb with external fixation followed by locked-plate osteosynthesis reduces local complications with a good functional result.

Unstable Cervical Spinal Injury in Children - Case Report and Review of the Literature.

Large studies about the management of pediatric patients with unstable flexion-distraction injuries of the midcervical spine are rare. We present the case of a 12-year-old girl who sustained a cervical spinal injury with unilateral facet dislocation and discuss details and problems of diagnostic procedures and treatment in the light of the recent literature. The management and pitfalls of a unilateral facet dislocation in a child are summarized. After initial reposition, a multisegmental instability with neurology developed. Although distraction-flexion cervical spine injuries are common in adults and often occur with concomitant neurological sequelae, they also can occur in the pediatric population. In conclusion, an MRI seems advisable. A treatment of postoperative malalignment with reposition via a halo-fixator cannot be recommended. Repositioning is possible but was lost when the fixator was removed. Comparing the historic and recent literature there is only weak evidence overall, nevertheless a ventral fusion seems to be the treatment option of choice.

Results of total hip replacement using the Robodoc surgical assistant system: clinical outcome and evaluation of complications for 97 procedures.

BACKGROUND: A computerized robotic surgical system was developed from 1986 by the Thomas J. Watson Research Center. In 1992 the system unit Orthodoc and the milling robot Robodoc were first used on humans. We present the results achieved with Robodoc-assisted total hip arthroplasty in 97 hips. METHODS: Between 1997 and 2002, 143 total hip replacements (128 patients) were performed using the Robodoc system. This is a consecutive series. Complete follow-up was possible in 97 hips at a mean follow-up period of 3.8 years. RESULTS: Technical complications directly related to the robotic device occurred in nine cases (9.3%). The pre-operative Merle d'Aubigne score was determined at 8.1 points compared to a post-operative mean score of 16.2. There was no sign of femoral stem loosening on radiographs. CONCLUSIONS: Robotic-assisted total hip arthroplasty with the Orthodoc/ Robodoc system achieves equal results as compared to a manual technique. However, there was a high number of technical complications directly or indirectly related to the robot.

Osteitis and Septic Arthritis after Tibial Head Fracture: Results of a Radical Treatment Regime.

OBJECTIVES: We report a series of 37 consecutive patients with both bone infection and septic arthritis of the knee following fracture of the proximal tibia. Aim of this study is to evaluate treatment results using a standardized treatment regime. The treatment regime consisted of an aggressive surgical approach to both the bone and the joint. In 61% the joint function was preserved, in the reminder an arthrodesis was required, there were no amputations. The difficulties in dealing with this condition are described as well as the clinical, radiological and occupational results. DESIGN/SETTING: Data collection was prospective. Data gathered at follow up included clinical examination, radiographs and the Rassmussen scoring system. Setting is a bone and joint infection and reconstruction unit of a tertiary referral hospital. PATIENTS/METHODS: Nine patients were female (24.3%). Mean age was 47.7 years (16.6-76.7 years). We classified fracture types according to Schatzker; ofwhich type VI fractures were the largest group with 13 cases. RESULTS: About 3.2 operations where required on average (1-7) for the treatment of infection. For 22 patients the joint function was salvaged. In the remaining cases an arthrodesis was required. CONCLUSIONS: The reported treatment regime gives reliable results for the treatment of combined bone and joint infection of the knee after fracture. In a large group of cases it was possible to salvage joint function. Comparison to other forms of treatment is not possible as there are no reported results so far.