Deformity Correction Planning Utilizing A Mobile Device Application

Radiographic analysis for surgical intervention involving the foot and ankle has historically been recognized as a vital component of pre-operative planning.¹ This is especially true when dealing with complex foot and ankle deformities.² The advent of digital radiology has made the process of radiographic evaluation one of greater convenience and reproducibility.³ The creation of programs available for computers, smartphones and tablets has made it possible for busy surgeons to have these images at their fingertips.    Prior to using digital radiographs, surgeons were forced to rely on more traditional methods of preoperative planning, including tracing paper cutouts, acetate templates and PowerPoint manipulations. The availability of PACS (picture archiving and communication systems), which stores digital images, has replaced traditional radiographic films. The use of computerized digital radiographs makes transmission of material easy and quick.    A recent study in US Radiology noted that “Digitalized radiography has become the standard modality in most orthopedic centers in industrialized countries over the past decade, creating the need for digitalized templating for the purposes of surgical planning.”⁴ Access to these digital images are available to physicians at hospitals and private practices as well as by remote login.⁵ This convenience has led to the advancement of computer software tools. Surgeons now have the ability to download these digital images for manipulation, measuring and planning via various commercial-based radiology software.    Although basic digital radiology software allows for measurement of distances and angles, many are not equipped with tools essential for performing deformity correction planning. Advancements in mobile technology software in the form of applications on computers, tablets and smartphones have changed how many surgeons are using digital photographs in planning for deformity correction.    One such application that is transforming the way surgeons plan for common to complex orthopedic procedures is Bone Ninja (Sinai Hospital, Baltimore). Bone Ninja is an application that was first introduced at the 2012 Baltimore Limb Deformity Course and is now available through Apple iTunes. Bone Ninja is an educational tool that allows users to upload a digital radiograph,plain film radiograph or even a photo of a radiograph for manipulation, measuring and deformity planning.    Physicians can use the program for assessment of length, angulation, translation and alignment. Special tabs within the application allow for placement of osteotomies, angulation/rotation of selected segments, the addition of internal/external fixation and other deformity correction-related tools. In addition, the Bone Ninja comes with a feature of image calibration, which authors have shown to be essential in using digital programs to accurately measure radiographs.⁶ The program also provides preloaded deformity cases with corrected solutions. These cases are available for those who wish to practice and gain experience in deformity planning principles.

What The Literature Reveals About Digital Radiographs And Pre-Op Planning Protocols

The medical and surgical literature has numerous examples of using digital radiographs in preoperative planning protocols. In particular, the use of computer programs, such as TraumaCad, reportedly provides essential tools in appropriately measuring limb length discrepancy.⁴ TraumaCad is a program that was developed for deformity planning and templating for many orthopedic procedures. Drs. Siddiqui and Lamm have an article in press for publication utilizing this software for the correction of flatfoot deformity. We found that utilizing the TraumaCad software accurately can predict the bone graft sizes needed for complete flatfoot correction with the Evans calcaneal osteotomy.    Several other studies have shown that digital radiographic measurements have similar or higher rates for inter- and intra-rater reliability in comparison to conventional counterparts.^1,3,6,7 Bone Ninja takes this idea forward by allowing the surgeon to have this tool readily available without having to access PACS.

Weighing The Pros And Cons Of The Bone Ninja Application

Dr. Lamm, the senior author, has long been implementing preoperative planning and deformity correction principles for common and complex foot and ankle pathology at the International Center for Limb Lengthening/Rubin Institute for Advanced Orthopedics. Dr. Lamm and various authors have discussed the benefits of preoperative planning within the foot and ankle surgical community.^8-13 Both Drs. Siddiqui and Lamm routinely use the Bone Ninja application for preoperative planning of most all foot and ankle surgeries. It is also a valuable tool for case preparation, illustrating to patients their pathology and the planned procedure. It also is a great platform to educate fellows and residents at the International Center for Limb Lengthening about deformity correction planning and principles.    Bone Ninja reinforces deformity planning principles by utilizing nomenclature that surgeons commonly use to discuss deformity correction. The application comes with preloaded cases that serve as an educational guide for those new to deformity planning. It also allows surgeons to upload their own cases to practice and plan for cases. The application has multiple help tools that provide new users tutorial guidance that makes using the application very easy. The touch features and tabs allow users to navigate through the application with minimal instruction, making the Bone Ninja very user friendly.    The advantages of the Bone Ninja application are its low cost, availability and accessibility in comparison to traditional deformity correction software. Traditional software programs, such as TraumaCad, are costly and limited licensing rules do not allow transferability to multiple computers. TraumaCad also requires a direct connection to the PACS at a hospital/practice. The ability to use the Bone Ninja application on multiple mobile devices allows surgeons to have planning available at their fingertips and bypasses the need for PACS accessibility. Therefore, the cost of Bone Ninja is a fraction of traditional planning software without the licensing limitations on multiple devices.    There are some limitations. One limitation is that the Bone Ninja application is limited to the iTunes store and is not available on other platforms. It is also yet to be validated as a device equivalent to traditional planning software.

Final Notes

In conclusion, we are currently in the process of publishing data to validate Bone Ninja as a planning tool for deformity correction. This along with future research is needed to transform Bone Ninja from an educational tool to one with surgical utility gained from scientific scrutiny. Current literature supports the use of digital software programs for radiographic analysis.⁶ Bone Ninja is an application that provides all the necessary tools to perform accurate radiographic deformity planning and allows one to do so from the convenience of a portable device. As technological advances continue to become integrated into modern medicine, it is pertinent that foot and ankle surgeons harness this emerging technology for the improvement of patient care.    Dr. Siddiqui is affiliated with the International Center for Limb Lengthening at the Rubin Institute for Advanced Orthopedics at Sinai Hospital in Baltimore.    Dr. Creech is a third-year resident at Temple University Hospital in Philadelphia.    Dr. Lamm is the Head of Foot and Ankle Surgery at the International Center for Limb Lengthening and the Director of the Foot and Ankle Deformity Correction Fellowship at the Rubin Institute for Advanced Orthopedics at the Sinai Hospital in Baltimore. He is the Rotation Director for the Podiatric Residency at Harvard Medical School. Dr. Lamm is a Fellow of the American College of Foot and Ankle Surgeons. He also is an editor for the Journal of Foot and Ankle Surgery and serves on the PRESENT Podiatry Advisory Board. References 1. Varghese B, Muthukumar N, et al. Reliability of measurements with digital radiographs—a myth. Acta Orthop Belg. 2011;77(5):622-625. 2. Paley D, Tetsworth K. Mechanical axis deviation of the lower limbs. Preoperative planning of multiapical frontal plane angular and bowing deformities of the femur and tibia. Clin Orthop Relat Res. 1992;(280):65-71. 3. Segev E, Hemo Y. Intra- and interobserver reliability analysis of digital radiographic meausrements for pediatric orthopedic parameters using a novel PACS integrated computer software system. J Child Orthop. 2010:4(4):331–341. 4. Steinberg E, Segev E. Pre-operative planning using the Traumacad software system. US Radiology. 2010;2(1):87–90. 5. Strickland NH. PACS (picture archiving and communication systems): filmless radiology. Arch Dis Child. 2000;83(1):82-6. 6. Kumar PG, Kirmani SJ, Humberg H, Kavarthapu V, Li P. Reproducibility and accuracy of templating uncemented THA with digital radiographic and digital TraumaCad templating software. Orthopedics. 2009;32(11):815. 7. Khakharia S, Bigman D, Fragomen AT, Pavlov H, Rozbruch SR. Comparison of PACS and hard-copy 51-inch radiographs for measuring leg length and deformity. Clin Orthop Relat Res. 2011;469(1):244–250. 8. Siddiqui NA, Herzenberg JE, Lamm BM. Supramalleolar osteotomy for realignment of the ankle joint. Clin Podiatr Med Surg. 2012;29(4):465-482. 9. Lamm BM, Gesheff MG, Salton HL, Dupuis TW, Zeni F. Preoperative planning and intraoperative technique for accurate realignment of the Dwyer calcaneal osteotomy. J Foot Ankle Surg. 2012;51(6):743-8. 10. Mendicino RW, Catanzariti AR, John S, Child B, Lamm BM. Long leg calcaneal axial and hindfoot alignment radiographic views for frontal plane assessment. J Am Podiatr Med Assoc. 2008;98(1):75-8. 11. Mendicino RW, Lamm BM, Catanzariti AR, Statler TK, Paley D. Realignment arthrodesis of the rearfoot and ankle: a comprehensive evaluation. J Am Podiatr Med Assoc. 2005;95(1):60-71. 12. Lamm BM, Mendicino RW, Catanzariti AR, Hillstrom HJ. Static rearfoot alignment: a comparison of clinical and radiographic measures. J Am Podiatr Med Assoc. 2005;95(1):26-33. 13. Lamm BM, Paley D. Deformity correction planning for hindfoot, ankle, and lower limb. Clin Podiatr Med Surg. 2004;21(3):305-26.