The effect of contouring on fatigue resistance of three types of fracture fixation plates

Lin, Angela; Fechter, Chelsea M.; Magill, Mark; Wipf, Felix; Moore, Thomas J.; Guldberg, Robert E.

doi:10.1186/s13018-016-0439-1

Cited by 15 publications

(13 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Techniques of surgical repair of the vertical ramus of the mandible described include external 27 and internal fixation, with internal fixation using an LCP considered ideal. 1,2 However, the use of a LCP in this area is not without some important limitations: considerable bending of the plate is required to match the angle of the mandible with subsequent weakening of the construct, 7 if the surgeon accidentally bends the plate across the plate hole, the locking function is lost, 9 if the plate is over-bent, any attempt at reverse bending likely further compromises the repair quality 10,11 and the locking screws are expensive. The use of the SOP system in this case helped to overcome some of these limitations.…”

Section: Discussionmentioning

confidence: 99%

“…9 If the surgeon over-estimates the angle and has to reverse bend the LCP, the resultant deformation of the constituent metal decreases the stiffness and strength of the implant and plate failure becomes more likely. 10,11 Finally, but perhaps most fatefully, the use of multiple locking screws quickly becomes expensive and may deter owners from pursuing repair.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Internal Fixation of a Complicated Mandibular Fracture in a Filly Using a String-of-Pearls Locking Plate Assisted by a 3D Printed Model

et al. 2020

View full text Add to dashboard Cite

Objective The aim of this study was to describe the successful surgical treatment of a complicated mandibular fracture with a 3.5 mm string-of-pearls (SOP) locking plate in a 5-month-old Appaloosa filly presenting with neurological signs. Study Design This is a case report. Results The neurological signs were due to severe head trauma and stabilized with medical treatment. Financial concerns initially prevented advanced imaging; radiographs identified a mandibular symphysis fracture, a fracture of the left vertical ramus that originated at the junction between the horizontal and vertical ramus and extended toward the coronoid process and rostral maxillary fractures. Following intra-dental wiring of the symphysis fracture, a lateral malocclusion developed. Computed tomography additionally identified fractures of the right wing of the basisphenoid bone, right zygomatic arch, left paracondylar process and the lateral body of the mandible. The vertical ramus fracture was repaired utilizing a 20-hole 3.5 mm SOP plate contoured to the ventral aspect of the angle of the mandible. A scaled (1:4) three-dimensional printed model aided pre- and intra-operative surgical planning. The filly was comfortable and eating well at the 4-week recheck. Radiographs showed good callus formation at the maxilla, healing of the mandibular symphysis and ramus. Just prior to the 10-week recheck, the filly suffered severe enterocolitis and was euthanatized. Conclusion The locking function of the SOP plate provided adequate stability for the fracture to heal without the expense of locking screws. The three-dimensional printed model aided in navigation of the complex fracture without the availability of fluoroscopy.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Internal Fixation of a Complicated Mandibular Fracture in a Filly Using a String-of-Pearls Locking Plate Assisted by a 3D Printed Model

et al. 2020

View full text Add to dashboard Cite

show abstract

“…18,19 Multiple contouring may cause a decreased fatigue resistance, through the initiation of microscopic cracks followed by gradual propagation and eventually fracture. 20,21 Fundamentally, plate hydroforming can increase the interfacial fit between the plate and mandible. Although the reconstruction plate is a load-bearing plate, nevertheless load can be transferred by physical contact.…”

Section: Discussionmentioning

confidence: 99%

Improved accuracy of hemimandibular reconstructions involving the condyle by utilizing hydroformed reconstruction plates rather than hand‐bent stock plates

et al. 2019

View full text Add to dashboard Cite

Background Computer‐aided design/computer‐aided manufacturing (CAD/CAM) surgical templates allow precise mandibular reconstructive surgery. However, their clinical accuracy is limited by manual plate bending. Digitally hydroformed plates maintain a digital workstream in virtual planning. Methods Twelve patients with Brown's class IIc mandibular defects were randomized into two groups: group I (experimental), the reconstruction plate was digitally hydroformed, and group II (control), surgeries were performed CAD/CAM guided with the reconstruction plate manually prebent. The linear and angular deviations of reconstruction outcomes were compared to surgical simulation in both groups. Results The mean linear and angular deviations of middle and posterior segments were 2.14 ± 0.79 mm, 3.71 ± 0.95 mm, 8.73° ± 1.91°, and 9.06° ± 0.96° in group I and 4.31 ± 0.78 mm, 6.74 ± 1.40 mm, 16.35° ± 0.72°, and 31.48° ± 3.38° in group II, respectively. Measurements in group I were significantly lower than group II (P < .005). Conclusion Digital hydroforming for plate prebent is a reliable method that helps improving the clinical accuracy of CAD/CAM‐guided mandibular reconstruction surgery.

show abstract

“…-Image binarization-a process of converting a colour or greyscale digital image to a black and white image. 16 -Otsu's cluster variance maximization method-one of the most successful image binarization methods based on image variance. 17 -Canny edge detection-an algorithm that allows detection of a wide range of edges in images.…”

Section: Glossarymentioning

confidence: 99%

How Do the Locking Screws Lock? A Micro-CT Study of 3.5-mm Locking Screw Mechanism

Kaczmarek¹,

Bartkowiak

Paczos

et al. 2020

Vet Comp Orthop Traumatol

View full text Add to dashboard Cite

Objective To quantify the amount of the screw head thread and the plate hole thread connection in two 3.5 mm locking plates: Locking Compression Plate (LCP) and Polyaxial Locking System (PLS). Materials and Methods A micro - CT scan of a screw head - plate hole connection was performed pre- and post destructive tests. Tests were performed on bone surrogates in a fracture gap model. The 3.5 LCP and 3.5 PLS plates, with 3 perpendicular screws per segment were used in a destructive static test. The 3.5 PLS plates with mono- and polyaxial screws were compared in a cyclic fatigue tests in two orthogonal directions. Pre - and post - test scan datasets were compared. Each dataset was converted into serial images depicting sections cut orthogonally to locking screw axis. The amount of engagement was detected through automated image postprocessing. Results The mean amount of the thread connection for the LCP was 28.85% before and 18.55% after destructive static test. The mean amount of the connection for the PLS was 16.20% before and 14.55% after destructive static test. When inserted monoaxially, the mean amount of the connection for the PLS screws was 14.4% before and 19.24% after destructive cyclic test. The mean amount of the connection for the polyaxial inserted PLS screws when loaded against plate thickness was 2.99% before and 2.08% after destructive cyclic test. The mean amount of the connection for the polyaxial inserted PLS screws when loaded against plate width was 3.36% before and 3.93% after destructive cyclic test. The 3D visualization of the thread connection showed that the initial interface points between screw head and plate hole are different for both LCP and PLS after the destructive testing. Depending on the type of applied force, there was either loss or increase of the contact. Clinical Relevance Micro-CT offers news possibilities in locking implant investigation. It might be helpful in better understanding the nature of locking mechanism and prediction of possible mode of failure in different systems.

show abstract

The effect of contouring on fatigue resistance of three types of fracture fixation plates

Cited by 15 publications

References 18 publications

Internal Fixation of a Complicated Mandibular Fracture in a Filly Using a String-of-Pearls Locking Plate Assisted by a 3D Printed Model

Internal Fixation of a Complicated Mandibular Fracture in a Filly Using a String-of-Pearls Locking Plate Assisted by a 3D Printed Model

Improved accuracy of hemimandibular reconstructions involving the condyle by utilizing hydroformed reconstruction plates rather than hand‐bent stock plates

How Do the Locking Screws Lock? A Micro-CT Study of 3.5-mm Locking Screw Mechanism

Contact Info

Product

Resources

About