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Kilian Wegmann - One of the best experts on this subject based on the ideXlab platform.
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plate osteosynthesis of Proximal Ulna fractures a biomechanical micromotion analysis
Journal of Hand Surgery (European Volume), 2017Co-Authors: Michael Hackl, L P Muller, Katharina Mayer, Mareike Weber, Manfred Staat, Roger P Van Riet, Klaus J Burkhart, Kilian WegmannAbstract:Purpose Double plating has been promoted, in recent years, as an alternative treatment method for Proximal Ulna fractures. This study aimed to compare the biomechanical properties of double-plate osteosynthesis with posterior plate fixation using a novel investigational design utilizing a 3-dimensional camera system to analyze fracture micromotion. Methods Fourteen fresh-frozen specimens were available for this study. Mayo type IIA fractures of the olecranon were created and internal fixation was performed with either an angular stable posterior plate or angular stable double plates. Fracture micromotion was evaluated by means of digital image correlation with a 3-dimensional camera system before and after dynamic cyclic loading from 15° to 90° of elbow flexion with a pulling force of 25 N to 80 N. Results Micromotion of fragments was less pronounced in double-plate osteosynthesis when compared with single plates before and after cyclic loading. However, overall results were similar. Two of the single plates failed during cyclic loading but there were no failures in the double plates. Conclusions This biomechanical analysis shows that single and double plating results in comparable stability of fixation. Although the double-plating technique tends to provide more stable fixation, relevant differences were not observed. Clinical relevance Double plating potentially represents an efficient option for fixation of Proximal Ulna fractures. It could decrease the risk of soft tissue complications owing to their low profile and the superior soft tissue coverage.
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reconstruction of monteggia like Proximal Ulna fractures using different fixation devices a biomechanical study
Injury-international Journal of The Care of The Injured, 2016Co-Authors: Kilian Wegmann, Johannes Christof Hopf, L P Muller, K Engel, Emmanouil Skouras, Michael Hackl, Thomas C KoslowskyAbstract:Abstract Background Comminuted Proximal Ulna fractures are rare and reconstruction of these fractures is discussed controversially. The aim of this study was to test three currently available plate devices in a standardized comminuted four-part fracture model created in Proximal Ulna sawbones. Material and methods A standardized four-part fracture of the Proximal Ulna was created in 80 sawbones. Reconstruction was performed by five experienced test surgeons according to a standardized reconstruction protocol. Each surgeon reconstructed 4 fractures with a 3.5 mm eight-hole reconstruction plate, 4 fractures with seven-hole third-tubular double plates and 4 fractures with a 3.5 mm anatomical seven-hole locked angle Proximal Ulna plate. 4 more fractures were reconstructed with simple K-wires as a reference construct for further experiments. Outcome measurements were time for reconstruction, quality of reconstruction and stability of the reconstruction. Stability testing was done in 90° and 30° flexion of the elbow. Testing in 30° flexion was done to test the anteroposterior stability regarding the fixed coronoid process. Results Time for reconstruction was significantly less for K-wire fixation than for the plate devices. Time for reconstruction plating and locked angle plating was significantly lower than for double plating (p 0.05). For all devices the testing in 30° flexion showed a significantly higher rigidity compared to 90° flexion. Conclusion The locked angle plate system showed the highest stability in 90° of elbow flexion. Each implant was more stable in 30° flexion than in 90° flexion. Testing of the anterior stability of the elbow did not show any differences between the different implants. Because of the superior stability of this device, we conclude that locked angle plating should be preferred for reconstruction of monteggia like complex Proximal Ulna fractures.
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Proximal Ulna fractures
Obere Extremität, 2014Co-Authors: Kilian Wegmann, Michael Hackl, Klaus J BurkhartAbstract:Fractures of the olecranon are common in adults and can be complex lesions. Triceps pull is acting as a dislocating force. The soft tissue envelope at the back of the Proximal Ulna is only tenuous. In fractures following direct trauma, accompanying soft tissue lesions are common. Combined with swelling by fracture hematoma and oedema, skin closure can be challenging. Bulky implants increase the risk of wound healing issues. As another factor, fracture configuration and bone quality play an important role in fixing these lesions. While conservative treatment has been advocated only for low demand patients, non-comminuted simple fractures are amenable to cerclage techniques. With figure of eight cerclages, strong fixation is feasible. However, the procedure should not be seen as a particularly easy procedure. Misplacement of the wires may lead to failure of the construct. Incomplete burial of the cerclage locks may lead to iatrogenic complications with wound healing. The comminuted fractures should be fixed using osteosynthesis plates. On the market, different types of plates are available. Standard 3.5 LCP can help to stabilize uncomminuted distal olecranon fractures. The comminuted fractures of the Proximal portion of the olecranon demand specific features of the plates, so that the sometimes small Proximal fragment can securely be stabilized with as many screws as possible. As a new concept, double plating of the olecranon is being done with one plate at the medial aspect of the olecranon and a second one on the lateral aspect. In that way, the plates can be hidden under the anconeus muscle laterally and the flexor carpi Ulnaris muscle medially. By that, optimal soft tissue management is possible. Whether double plating of the olecranon is of significant benefit will be investigated by clinical studies in the future.
Dominique M Rouleau - One of the best experts on this subject based on the ideXlab platform.
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impact of olecranon fracture malunion study on the importance of puda Proximal Ulna dorsal angulation
Injury-international Journal of The Care of The Injured, 2016Co-Authors: Julie Chapleau, Frederic Alg, Edward J Harvey, Jeremie Menard, Frederic Vauclai, Yves G Laflamme, Jonah Hebertdavies, Dominique M RouleauAbstract:Abstract Purpose The Proximal Ulna Dorsal Angulation (PUDA) is part of the Proximal Ulna’s normal anatomy. The importance of restoring Ulnar anatomy characteristics precisely after olecranon fracture is not known, however, failure to recreate the PUDA after surgery may result in poorer functional outcomes. The purpose of this study is to evaluate the impact of minimal Proximal Ulna malunion on elbow ROM and function at least one year after olecranon ORIF. Method A retrospective comparative cohort study took place in three level-1 trauma centers. Forty-nine adult volunteers who underwent ORIF for olecranon fracture were included. Patients were separated into two groups according to PUDA malreduction—defined as more than 5° of difference between the fractured and the contralateral elbow. Outcome measurements Radiographic ROM measurement, demographic data and quality of life questionnaires were recorded (PREE, MEPS, Q-DASH, SF12, VAS). Results The mean follow up was 3 years and 9 months (1–7 years). There was no difference in terms of outcome, quality of reduction or range of motion between patients treated with plate or tension band. The mean PUDA on the fracture side was different from the normal side (2.20 vs 4.90, p Conclusion Incidence of olecranon malunion—as defined by PUDA measurement − was 29% and it was associated with decreased elbow range of motion. Alcohol consumption was correlated with a worse prognosis in our series of patients. Tension band and plate fixation can maintain a good reduction in terms of PUDA and the choice of fixation method does not influence outcome. Level of evidence III Therapeutic study.
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radial head subluxation after malalignment of the Proximal Ulna a biomechanical study
Journal of Orthopaedic Trauma, 2014Co-Authors: Emilie Sandman, George S. Athwal, Fanny Canet, Yvan Petit, George Y Laflamme, Dominique M RouleauAbstract:Objectives:Understanding the anatomy of Proximal Ulna is important when treating complex injuries, since nonanatomic reconstruction may lead to malunion, arthrosis, and instability. The Proximal Ulna has a sagittal bow, termed the Proximal Ulna dorsal angulation (PUDA). The purpose of this study was
George S. Athwal - One of the best experts on this subject based on the ideXlab platform.
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reconstruction techniques for fractures of the Proximal Ulna and radial head
2016Co-Authors: James M Mclean, George S. Athwal, Parham DaneshvarAbstract:The decision to operate on an elbow fracture is variable and is dependent on several factors. Careful consideration should be given to patients with multiple comorbidities, a high risk of non-compliance and patients in whom the procedure is unlikely to meet their expectations. Surgery is generally recommended for fractures that cannot be reduced by closed means, inherently unstable fracture patterns and for fractures with significant ligamentous injuries in which the stability of the elbow is compromised
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radial head subluxation after malalignment of the Proximal Ulna a biomechanical study
Journal of Orthopaedic Trauma, 2014Co-Authors: Emilie Sandman, George S. Athwal, Fanny Canet, Yvan Petit, George Y Laflamme, Dominique M RouleauAbstract:Objectives:Understanding the anatomy of Proximal Ulna is important when treating complex injuries, since nonanatomic reconstruction may lead to malunion, arthrosis, and instability. The Proximal Ulna has a sagittal bow, termed the Proximal Ulna dorsal angulation (PUDA). The purpose of this study was
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Fractures and Dislocations of the Proximal Ulna and Radial Head
Essentials In Elbow Surgery, 2014Co-Authors: Parham Daneshvar, J. Whitcomb Pollock, George S. AthwalAbstract:This chapter presents a comprehensive review of isolated fractures of the Proximal Ulna and radial head, along with the most complex patterns of injury, including fracture-dislocations of the elbow. The epidemiology, pathomechanics, and diagnostic plan are exposed along with modern strategies for elbow reconstruction. Tips and tricks for radial head reconstruction or arthroplasty, coronoid fixation, and ligament repair are described. A standardized protocol for dealing with the most complex elbow fracture-dislocations and an algorithm to understand the most appropriate treatment for these patients are provided.
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the Proximal Ulna dorsal angulation a radiographic study
Journal of Shoulder and Elbow Surgery, 2010Co-Authors: D M Rouleau, Kenneth J Faber, George S. AthwalAbstract:Background Recognition of the Proximal Ulna dorsal angulation (PUDA) is important for anatomic reduction of Proximal Ulna fractures, nonunions, malunions, or osteotomies, especially when using newer straight precontoured Ulnar plates. The purpose of this study was to characterize the PUDA in 50 patients with bilateral elbow radiographs. Materials and methods Commercial software was used to magnify 100 bilateral elbow radiographs 4 times. The PUDA was measured from the intersection of lines perpendicular to the subcutaneous border of the olecranon and the Ulnar shaft. The olecranon tip-to-apex distance of the PUDA was also measured. Three orthopedic surgeons independently examined the radiographs, and intraobserver and interobserver reliability was calculated using intraclass correlation. Results A PUDA was present in 96% of radiographs. The average PUDA was 5.7° (range, 0°-14°). The Pearson correlation coefficient for a side-to-side comparison was 0.860 ( P Discussion A mean PUDA of 5.7° is present in 96% of patients at an average of 47 mm distal to the olecranon tip. Measurement of the PUDA has good-to-excellent interobserver and intraobserver reliability. Conclusion Contralateral PUDA measurements are reliable in determining the angle in patients with comminution or distorted anatomy. Recognition of the PUDA may be helpful in anatomic plating of the Ulna. Recognition of the PUDA may be helpful in anatomic plating of the Ulna for fractures, nonunions or malunions. Level of evidence Radiographic study.
Goo Hyun Baek - One of the best experts on this subject based on the ideXlab platform.
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intra articular osteoid osteoma in the Proximal Ulna combined with radial head subluxation a case report
Journal of Shoulder and Elbow Surgery, 2012Co-Authors: Ji Hyeung Kim, Hyuk Jin Lee, Goo Hyun BaekAbstract:Osteoid osteoma is a relatively common benign bone tumor that was first described by Jaffe in 1935. Its typical clinical feature is pain, which is worse at night and relieved by nonsteroidal anti-inflammatory drugs (NSAIDs). Typical radiologic findings are a nidus with a small radiolucent area within an extensive reactive cortical thickening. This tumor has a predilection for the diaphysis or metaphysis of long bones, with 50-60% occurring in the femur or tibia. However, localization in the elbow is a very rare presentation, and shows an atypical picture that causes both diagnostic delay and therapeutic problems. We herein report a case of a 19-year-old man who had pain and limited motion of the left elbow as a result of osteoid osteoma at the sigmoid notch of the Proximal Ulna. Anterior subluxation of the radial head was also observed by simple radiographs. En bloc resection and synovectomy resulted in pain relief, motion recovery, and reduction of the subluxated radial head. The patient consented when asked if data concerning his case could be submitted for publication.
Wolfgang Pichler - One of the best experts on this subject based on the ideXlab platform.
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three dimensional morphometry of the Proximal Ulna a comparison to currently used anatomically preshaped Ulna plates
Journal of Shoulder and Elbow Surgery, 2012Co-Authors: Paul Puchwein, Thomas A Schildhauer, Sylvia Schoffmann, Nima Heidari, Gunter Windisch, Wolfgang PichlerAbstract:Background Anatomically preshaped plates are increasingly used for stabilization of comminuted olecranon and Monteggia fractures. The purposes of this study were to investigate the morphology of the Proximal Ulna and to compare morphologic findings with geometry of 4 preshaped Ulna plates. Materials and methods Forty human elbows (mean age, 68 years; range, 21-98 years) were measured by 2 independent observers using 64-slice computed tomography scans and 3-dimensional measuring software. Results Measurements showed a mean dorsal hook angle of 95.3° ± 9.0° (range, 74.7°-110.8°) with gender-specific differences (mean, 92.2° ± 8.1° in men and 98.3° ± 8.9° in women; P = .029); a mean distance from the tip of the olecranon to the Proximal edge of the Ulna of 24.7 ± 2.7 mm (range, 20-30.5 mm) with gender-specific differences ( P = .00068); a mean varus angulation of 14.3° ± 3.6° (range, 5.8°-21.2°); and a mean anterior angulation (Proximal Ulna dorsal angulation) of 6.2° ± 2.7° (range, 1.0°-11.2°). The investigated plates offered a tolerable (± standard deviation) hook angle in 25% to 68%, an appropriate varus angulation in 0% to 20%, and an adequate anterior angulation in 23% to 88%. The intraclass correlation coefficient was between 0.74 and 0.91. Conclusion The Proximal Ulna has a gender-specific and variable morphology. Some currently used anatomically preshaped Proximal Ulna plates differ significantly from these morphologic findings. In cases where reduction is not exactly possible, application of an "anatomically preshaped" plate may result in poor reduction. Especially in case of Monteggia fractures with instability of the radiocapitellar joint, surgeons could be misguided by plates that do not incorporate anterior angulation, resulting in subluxation of the radial head on the capitellum.
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the anatomy of the Proximal Ulna
Journal of Shoulder and Elbow Surgery, 2007Co-Authors: Gunther Windisch, H Clement, W Grechenig, N P Tesch, Wolfgang PichlerAbstract:The posterior border of the Ulna is the most important bony landmark for all dorsal surgical approaches and the guideline for open reduction, internal fixation of displaced comminuted fractures of the Proximal Ulna. We examined 74 cadaveric specimens to evaluate the anatomy of the Proximal Ulna, especially the course of the posterior border, the point of varus angulation, the width of the shaft, and the relationship of the posterior border to the interosseous and anterior ones. In 63 specimens, the mean point of varus angulation was 85.4 mm, and the average angulation angle was 17.7°. In 11 specimens, the posterior border was either radially bowed or the bow was poorly defined and not localized to a specific area along the length of the bone. In conclusion, the variations of the Proximal Ulna have to be considered if dorsal plates and intramedullary screws are used.
