Proximal third humeral shaft fractures fixed with long helical PHILOS plates in elderly patients

The optimal treatment for humeral shaft fracture remains controversial. Although a large proportion of these fractures can be treated without surgery, a recent study, involving a randomized controlled trial, compared bridge plate with functional brace fixation for humeral shaft fractures and concluded that surgical plating has a statistically significant advantage with a better DASH score, lower non-union rate, and lower residual deformity rate [1]. As for proximal third humeral shaft fractures, they were thought to be complicated with a higher non-union rate when treated conservatively compared with middle and distal fractures [2, 5, 16]. Since the helical plating technique was introduced for the treatment of humeral fractures, some studies have shown that this technique resulted in increased stiffness compared to fixation with a straight plate under torsional loading and produced satisfactory clinical outcomes [14, 17]. However, how to produce a suitable helical plate for each individual patient is a big question for surgeons. Previous studies have proven that the 3D printing technique is a good tool for designing surgical plans and pre-contouring plates used to treat other bone fractures [18–20]. Our results demonstrate the benefit of pre-contouring plates on a 3D-printed model for this special technique.

In this study, all kinds of fractures (from type A to type C) were treated by helical plating technique, and satisfactory outcomes were obtained. It was coincident with our previous cadaveric study results [11], so we thought this special technique was a good choice for these fractures. Previously, Stedtfeld and Biber reported that approximately 49.3% of the proximal third humeral shaft fractures extend into the humeral head and that this type of fracture cannot be characterized by conventional AO classification [6]. In our study, a total of 41.3% (19/46) of fractures involved the proximal humerus, a rate slightly lower compared with their report, but still a high rate of these fractures. Consequently, attention should be paid on the proximal third humeral shaft fractures since about half of them need adequate proximal fixation.

At the 1-year follow-up visit, all fractures were healed and none of the patients had suffered non-union, an outcome better than that reported for other treatment methods [1, 2, 5, 9, 21–23]. The mean union times of the Synbone group and the 3D-printed groups were 16.16 and 15.57 weeks, respectively, which was similar to other studies even though our patients were older than in other studies [11, 17, 24]. Functional evaluations were satisfactory but were worse than those reported by others who conducted the same surgeries (Constant-Murley score 76.80, 76.95 vs. 88.6) [13, 17]. This may be attributed to the fact that our population was much older, so that humeral fracture might be combined with rotator cuff degeneration in our enrolled patients.

The primary outcomes of this study were that surgical duration and blood loss were reduced by the use of a 3D-printed model for pre-contouring the plates before surgery. This result was consistent with our hypothesis and can be explained by the fact that the humeri of older patients in our country are much shorter than the standard Synbone, requiring surgeons to adjust the plates during surgery. Since the 3D-printed model represented the actual size of the bone, the plates pre-contoured on these models were always suitable for fixing the fractures. Because of MIPO technique application, there was only 15 ml of blood loss difference between the two groups; maybe it was not clinically relevant, but on the whole, it reduced 12.5% of blood loss volume and presented a small part of the benefit of 3D-printed technique.

We compared the outcomes between the two grades of surgeons in the 3D-printed group. Although senior attending doctors are much more experienced than junior attending doctors, the results showed that there was no significant difference between them in terms of outcome. We believed that the 3D printing technique would make this novel technique much easier and make it available for use by less specialized surgeons. However, since all fractures in the Synbone group were finished by senior attending doctors, it was impossible to compare the results with a control group.

There are some limitations to this study: (I) the retrospective design limits the level of evidence and only represents one single center; (II) some patients who died within 1 year of surgery are excluded from this study, which may influence the final results; (III) all these surgeries were finished by surgeons in one trauma center, so personal differences cannot be avoided; and (IV) this study only included Asian population, and maybe the results could be challenged by other races because of different skeletal sizes.

Third Thumb is the 3D-printed prosthesis you didn't know you needed until now

Why it matters to you

This Third Thumb prosthetic may look weird, but it could actually be pretty handy. No pun intended.

Want to look like a cyborg from some dystopian sci-fi movie about survivors in a post-apocalyptic nuclear wasteland? Then you will probably want to check out this awesome 3D-printing prosthetics project from Dani Clode, a graduate student at London’s Royal College of Art (RCA). Clode developed a functional prosthetic third thumb that is capable of carrying out an impressive range of motions designed to extend the wearer’s abilities.

“The Third Thumb is a 3D-printed thumb extension for your hand, controlled by your feet,� Clode told Digital Trends. “The Third Thumb investigates the relationship between the body and prosthetic technology in new ways. It is part tool, part experience, and part self-expression; a model by which we better understand human response to artificial extensions.�

The thumb’s 3D parts are connected using a Bowden cable system, similar to a bike brake, that is made of Teflon tubing and wire. “3D printing is the perfect medium for this project, as it enables quick prototyping, customized designs for various hand sizes, and one-off production,� Clode said.

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The prosthesis’ motors are controlled via two pressure sensors retrofitted into the wearer’s shoes and receives its instructions via Bluetooth. Clode said she chose foot control for the project because she was inspired by the already strong connection between our hands and feet in various well-established products — such as driving a car, using a sewing machine, or playing the piano. The pressure sensors are designed to give plenty of control over the thumb, with one sensor controlling the flexion and extension, and the other controlling the thumb’s adduction and abduction. The results combine to create the kind of dynamic movement we would expect from, well, a regular thumb.

“The Third Thumb still needs more motor development before it could be commercialized,� Clode said. “The battery and motors are always the challenge with small wearables. I think it is a really unique product though, and it would be really interesting to develop it to that stage. The goal for the Third Thumb is to create a catalyst for society to consider human extension, framed in an approachable, accessible design. Success would be a widespread social engagement with The Third Thumb — from a jewelry designer to a falcon handler to a tattoo artist to a toddler. The more people who experience it, the better.�

Between this and some of the other awesome augmented human projects we have seen as of late, it seems the cyborg world really is no longer limited to science fiction.

Library is third department to get 3D printer

Published: Monday, April 21, 2014

Updated: Monday, April 21, 2014 22:04


photo By Jonathan A. Capriel | staff

Cody Behles, emerging technologies librarian, show students how to the MakerBot Replicator feeds plastic into the machine in order to create objects.

Walking into the McWherter Library, students might hear the rhythmic R2D2-like beeping and buzzing of the MakerBot Replicator 3D printer, or see the sculptures, toys and tiger’s heads fabricated from melted plastic, that sit beside it.

The 3D printer, which sits beside the Research and Information Services desk on the first floor, is one of two recently purchased printers that students can use without charge, Emerging Technologies Librarian Cody Behles said. 

“Many schools will allow you to come up with a design and print it for you,” Behles said while he demonstrated how to use the machine. “But they won’t let you touch the 3D printer. Memphis is one of the only campuses where students can learn how to use these on their own.”

Students are allowed to schedule up to four hours a week with the 3D printer. Behles teaches the 10-minute training course that must be completed before they are allowed to use the printer. 

“Everyone must also sign a release form,” Behles said. “It is actually pretty safe, but if you put your hand to close melted plastic you can burn your hand. Besides that, the printer is actually pretty straight forward.”

Released in March of this year, the fifth generation 3D printer is faster and easier to use than any other made by MakerBot, according to the company’s website. Behles said these were major reasons why this printer was chosen over the others. 

“We want students to be able to create their works of art,” Behles said. “On the library website, we have links to already made projects students can use. We even have downloads for three programs that will allow them to edit and build models. These things will be everywhere in the future, so it is better students get some practice with them now.”

Although the library has the newest printer on campus, it is not the only one that students have access to. The Crews Center for Entrepreneurship carries the 3D Touch and Cubex Trio, both made by 3D Systems. Director of the Crews Center Mike Hoffmeyer said they are in the process of getting a third one. 

“We are getting the MakerBot Replicator Z18,” Hoffmeyer said. “It is much bigger than the two we have currently. We will roll it out at the University Center when we get it so students can see what it can do.”

All 3D printing must be cleared by Hoffmeyer first. He requires student projects to promote “creativity, innovations or entrepreneurship.” However, he did explain that they can encompass a large variety of ventures. 

“We won’t let people just print out toys,” Hoffmeyer said. “We want students to work on prototypes that will hopefully be mass produced one day, but we have had some pretty fun things made here. We had students make jewelry and light up garments for a fashion show.”

The Crews Center also advises students on a business model and design their project. Derrick Meyers, a mechanical engineering junior, will help turn student drawings into a 3D model. 

“We show them how the programs run then we teacher them how to use it,” Meyers said. “We will help a student do everything from 3D modeling on the Auto CAD program to circuitry of their product.”  

However, the title of first and most expensive 3D printer on campus goes to the Herff College of Engineering. The Alaris 30 made by Objet was purchased two years ago and cost approximently $35,000. It is also only available for students in the engineering program said associate Professor Thomas Banning.

“Robert Hewett really pushed for us to get this and he usually the only person allowed to physically operate it,” Banning said while he picked up a white plastic crescent wrench. “It does amazing work. This tool has moving parts but was made all in one print.”  

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