Risk of Clavicle Fracture Following Coracoclavicular Ligament Reconstruction for High Grade Acromioclavicular Joint Dislocations

2012 ◽  
Author(s):  
Peter A. Gustafson ◽  
Mark Omwansa ◽  
Andrew G. Geeslin ◽  
Vani J. Sabesan
Keyword(s):  
Acromioclavicular Joint ◽  
Clavicle Fracture ◽  
Axial Loading ◽  
Reconstruction Technique ◽  
High Grade ◽  
Qualitative Comparison ◽  
Three Point Bending ◽  
Four Point Bending ◽  
Joint Dislocations ◽  
Cantilever Bending

Finite element models are used for qualitative comparison of the risk of fracture associated with clavicle tunnels in reconstruction of the coracoclavicular ligaments for treatment of high-grade acromioclavicular joint (ACJ) injury. The two-tunnel reconstruction technique is found likely to have higher fracture risk than the less anatomic single tunnel reconstruction. The models suggest that four point bending is more likely than three point bending, cantilever bending, or axial loading to differentiate the reconstruction techniques in a laboratory experiment. The results must be narrowly interpreted only in a laboratory context due to the limitations of the study.

Factors Predicting the Outcome After Arthroscopically Assisted Stabilization of Acute High-Grade Acromioclavicular Joint Dislocations

2019 ◽  
Vol 47 (11) ◽  
pp. 2670-2677 ◽  
Author(s):  
Nina Maziak ◽  
Laurent Audige ◽  
Carmen Hann ◽  
Marvin Minkus ◽  
Markus Scheibel
Keyword(s):  
Clinical Outcome ◽  
Acromioclavicular Joint ◽  
High Grade ◽  
Radiological Outcome ◽  
Ac Joint ◽  
Level Of Evidence ◽  
Outcome Parameters ◽  
Joint Dislocations ◽  
Anatomic Reduction ◽  
Arthroscopically Assisted

Background: Factors influencing the outcome after arthroscopically assisted stabilization of acute high-grade acromioclavicular (AC) joint dislocations remain poorly investigated. Purpose: To identify determinants of the radiological outcome and investigate associations between radiological and clinical outcome parameters. Study Design: Cohort study; Level of evidence, 3. Methods: The authors performed a retrospective analysis of patients who underwent arthroscopically assisted stabilization for acute high-grade AC joint dislocations. The following potential determinants of the radiological outcome were examined using univariable and multivariable regression analyses: timing of surgery, initial AC joint reduction, isolated coracoclavicular (CC) versus combined CC and AC stabilization, ossification of the CC ligaments, age, and overweight status. In addition, associations between radiological (ie, CC difference, dynamic posterior translation [DPT]) and clinical outcome parameters (Subjective Shoulder Value, Taft score [TS] subjective subcategory, and Acromioclavicular Joint Instability Score [ACJI] pain subitem) were evaluated using univariable analysis. Results: One hundred four patients with a mean (±SD) age of 38.1 ± 11.5 years were included in this study. The mean postoperative follow-up was 2.2 ± 0.9 years. Compared with patients with an overreduced AC joint after surgery, the CC difference was 4.3 mm (95% CI, 1.3-7.3; P = .006) higher in patients with incomplete reduction. Patients with anatomic reduction were 3.1 times (95% CI, 1.2-7.9; P = .017) more likely to develop DPT than those with an overreduced AC joint. An incompletely reduced AC joint was 5.3 times (95% CI, 2.1-13.4; P < .001) more likely to develop DPT versus an overreduced AC joint. Patients who underwent isolated CC stabilization were 4.8 times (95% CI, 1.1-21.0; P = .039) more likely to develop complete DPT than patients with additional AC stabilization. Significantly higher CC difference values were noted for patients who reported pain on the subjective TS ( P = .025). Pain was encountered more commonly in patients with DPT ( PTS = .049; PACJI = .038). Conclusion: Clinicians should consider overreduction of the AC joint because it may lead to favorable radiological results. Because of its association with superior radiographic outcomes, consideration should also be given to the use of additional AC cerclage.

scholarly journals Modified Weaver-Dunn Procedure Versus The Use of Semitendinosus Autogenous Tendon Graft for Acromioclavicular Joint Reconstruction

2016 ◽  
Vol 10 (1) ◽  
pp. 166-178 ◽  
Author(s):  
Galal Hegazy ◽  
Hesham Safwat ◽  
Mahmoud Seddik ◽  
Ehab A. Al-shal ◽  
Ibrahim El-Sebaey ◽  
...  
Keyword(s):  
Acromioclavicular Joint ◽  
Tendon Graft ◽  
Semitendinosus Tendon ◽  
Reconstruction Technique ◽  
Coracoclavicular Ligaments ◽  
Joint Reconstruction ◽  
Oxford Shoulder Score ◽  
Joint Dislocations ◽  
Rockwood Type Iii ◽  
Shoulder Score

Background: The optimal operative method for acromioclavicular joint reconstruction remains controversial. The modified Weaver-Dunn method is one of the most popular methods. Anatomic reconstruction of coracoclavicular ligaments with autogenous tendon grafts, widely used in treating chronic acromioclavicular joint instability, reportedly diminishes pain, eliminates sequelae, and improves function as well as strength. Objective: To compare clinical and radiologic outcomes between a modified Weaver-Dunn procedure and an anatomic coracoclavicular ligaments reconstruction technique using autogenous semitendinosus tendon graft. Methods: Twenty patients (mean age, 39 years) with painful, chronic Rockwood type III acromioclavicular joint dislocations were subjected to surgical reconstruction. In ten patients, a modified Weaver-Dunn procedure was performed, in the other ten patients; autogenous semitendinosus tendon graft was used. The mean time between injury and the index procedure was 18 month (range from 9 – 28). Clinical evaluation was performed using the Oxford Shoulder Score and Nottingham Clavicle Score after a mean follow-up time of 27.8 months. Preoperative and postoperative radiographs were compared. Results: In the Weaver-Dunn group the Oxford Shoulder Score improved from 25±4 to 40±2 points. While the Nottingham Clavicle Score increased from 48±7 to 84±11. In semitendinosus tendon graft group, the Oxford Shoulder Score improved from 25±3 points to 50±2 points and the Nottingham Clavicle Score from 48±8 points to 95±8, respectively. Conclusion: Acromioclavicular joint reconstruction using the semitendinosus tendon graft achieved better Oxford Shoulder Score and Nottingham Clavicle Score compared to the modified Weaver-Dunn procedure.

scholarly journals Early Versus Delayed Surgical Treatment of High-grade Acromioclavicular Joint Dislocations

2019 ◽  
Vol 3 (4) ◽  
pp. 255
Author(s):  
Alexandre Lädermann ◽  
Olivia Zbinden ◽  
Sébastien Piotton
Keyword(s):  
Surgical Treatment ◽  
Acromioclavicular Joint ◽  
High Grade ◽  
Joint Dislocations

Weighted or internal rotation radiographs are not useful in the classification of acromioclavicular joint dislocations

2020 ◽  
pp. 028418512093927
Author(s):  
Jonas S Nordin ◽  
Felicia Mogianos ◽  
Anders Hauggaard ◽  
Karl Lunsjö
Keyword(s):  
Confidence Interval ◽  
Internal Rotation ◽  
Acromioclavicular Joint ◽  
High Grade ◽  
Laboratory Studies ◽  
Exclusion Criteria ◽  
Injured Side ◽  
Joint Dislocations ◽  
The Mean

Background Weighted radiographs are performed to classify acromioclavicular joint dislocations; however, the evidence regarding their usefulness is conflicting. Laboratory studies suggest that internal rotation views can replace weighted radiographs, but this has not been clinically evaluated. Purpose To evaluate whether weighted or internal rotation radiographs uncovers more high-grade acromioclavicular joint dislocations than non-weighted radiographs. Material and Methods A total of 162 patients with acromioclavicular joint dislocations were prospectively included. After applying exclusion criteria, 140 remained. Three panorama radiographs, including both coracoclavicular intervals, were completed of each participant: first, a weighted radiograph with 5-kg weights suspended from the wrists; second, a non-weighted radiograph; and third, an internal rotation radiograph. The coracoclavicular intervals were measured by two radiologists independently, and measurements were translated into Rockwood classifications. The classifications and measurements derived from the different radiographic views were compared. Results Weighted radiographs caused no significant changes in classification. For the internal rotation views, there was a significant change in classification for radiologist 2; however, the reason was that more injuries were downgraded compared to the non-weighted views. Relative to the non-weighted radiographs, the mean increase of the coracoclavicular interval on the injured side in the weighted view was 0.5 mm (95% confidence interval [CI] 0.37–0.65) and in the internal rotation view 0.2 mm (95% CI 0.04–0.33). While these changes were statistically significant, they were small and not clinically important. Conclusion This study does not support the use of weighted and internal rotation radiographs in the classification of acromioclavicular joint dislocations.

Study on Multi-Axial Mechanical Properties of a Polyurethane Foam and Experimental Verification

2011 ◽  
Vol 311-313 ◽  
pp. 301-308
Author(s):  
Shou Hong Han ◽  
Zhen Hua Lu ◽  
Yong Jin Liu
Keyword(s):  
Mechanical Properties ◽  
Constitutive Model ◽  
Polyurethane Foam ◽  
Axial Compression ◽  
Axial Loading ◽  
Hydrostatic Compression ◽  
Model Parameters ◽  
Loading Conditions ◽  
Three Point Bending ◽  
Pu Foam

In order to investigate the multi-axial mechanical properties of a kind of PU (polyurethane) foam, some experiments in different loading conditions including uni-axial tension, uni-axial compression, hydrostatic compression and three-point bending were conducted. It is shown that the hydrostatic component influences yield behavior of PU foam, the yield strength and degree of strain hardening in hydrostatic compression exceed those for uni-axial compression. In terms of the differential hardening constitutive model, the evolution of PU foam yield surface and plastic hardening laws were fitted from experimental data. A finite element method was applied to analyze the quasi-static responses of the PU foam sandwich beam subjected to three-point bending, and good agreement was observed between experimental load-displacement responses and computational predictions, which validated the multi-axial loading methods and stress-strain constitutive model parameters. Moreover, effects of two foam models applied to uni-axial loading and multi-axial loading conditions were analyzed and compared with three-point bending tests and simulations. It is found that the multi-axial constitutive model can bring more accurate prediction whose parameters are obtained from the tests above mentioned.

Design of crack arrestors for ultra high grade gas transmission pipelines: simulation of crack initiation, propagation and arrest

2011 ◽  
Vol 2 (2) ◽  
pp. 307-319
Author(s):  
F. Van den Abeele ◽  
M. Di Biagio ◽  
L. Amlung
Keyword(s):  
Crack Initiation ◽  
Crack Propagation ◽  
Large Scale ◽  
Large Diameter ◽  
Pipe Material ◽  
High Grade ◽  
Gas Pipelines ◽  
Ductile Crack ◽  
Reinforced Plastics ◽  
Four Point Bending

One of the major challenges in the design of ultra high grade (X100) gas pipelines is the identification of areliable crack propagation strategy. Recent research results have shown that the newly developed highstrength and large diameter gas pipelines, when operated at severe conditions, may not be able to arrest arunning ductile crack through pipe material properties. Hence, the use of crack arrestors is required in thedesign of safe and reliable pipeline systems.A conventional crack arrestor can be a high toughness pipe insert, or a local joint with higher wall thickness.According to experimental results of full-scale burst tests, composite crack arrestors are one of the mostpromising technologies. Such crack arrestors are made of fibre reinforced plastics which provide the pipewith an additional hoop constraint. In this paper, numerical tools to simulate crack initiation, propagationand arrest in composite crack arrestors are introduced.First, the in-use behaviour of composite crack arrestors is evaluated by means of large scale tensile testsand four point bending experiments. The ability of different stress based orthotropic failure measures topredict the onset of material degradation is compared. Then, computational fracture mechanics is applied tosimulate ductile crack propagation in high pressure gas pipelines, and the corresponding crack growth inthe composite arrestor. The combination of numerical simulation and experimental research allows derivingdesign guidelines for composite crack arrestors.

Sign in / Sign up

Export Citation Format

Share Document