Summary The VIRTUGUIDE™ Software* utilizes AI technology to automatically analyze the patient’s anatomy based on provided CT or X-ray images and assists in selecting the most appropriate Virtual Alignment and Correction (VAC) Guide based on the patient deformity, providing a consistent and streamlined approach to planning for bunion correction. Early users experienced a reduced operative time by using the software recommended, patient matched VAC Guide for deformity correction compared to their previous technique. In addition, they agreed that the software recommended, patient matched VAC Guide improved the consistency of achieving surgical correction compared with their prior technique. Related Implants DYNABUNION™ Plates fixation with implant is described as compatible with a range of J and JMedTech Lapidus fixation options, including DynaBunion™ Lapidus constructs TriLEAP™ Plates fixation with implant is described as compatible with TriLEAP™ Lapidus plate options Continuous Compression Implants fixation with implant is described as compatible with continuous compression implant options CCHS Screws cannulated compression headless screw options are shown as potential fixation options Indications Indications general Lapidus indications often include hallux valgus (bunion) deformity tarsometatarsal (TMT) joint fusion Contraindications general contraindications and risk factors often considered for elective arthrodesis include active infection at or near the surgical site insufficient bone quality or severe osteoporosis that would compromise fixation or fusion patients unable to undergo required preoperative imaging needed for patient-matched planning severe neuropathy noncompliance with post-op restrictions Preoperative Planning Imaging CT configured for weight bearing CT scans of the entire foot images should be DICOM files image requirements slice thickness less than 1.25 mm slice spacing less than 1.0 mm pixel spacing less than 0.9 mm per-instance resolution at least 320 by 320 series should include all axial slices with low observational noise and good contrast between bone and tissue imaging is recommended to avoid metallic materials, such as prostheses x-ray configured for anterior-posterior (AP) X-rays of the entire foot images should be DICOM modality DX or CR with pixel spacing less than 0.9 mm and per-instance resolution at least 512 by 512 must be calibrated prior to software analysis using X-ray scaling factors to enable AI-automated measurements in mm if a magnification factor is unavailable and a default value is used, the software does not display measurements in mm and shows only angle calculations imaging is recommended to avoid metallic materials, such as prostheses Software analysis and planning workflow create a case, upload CT or X-ray images, and review image slices prior to planning approve the AI-automated anatomy analysis by adjusting and approving anatomical landmarks as needed plan the case using an automatically generated virtual deformity correction with updated plan measurements and a suggested patient-matched VAC Guide adjust IM and FP angle correction as desired and manually adjust measurements and instrument choices as needed optionally template various implant options to assess placement and fit when CT scans are used review and approve the plan prior to export, noting the plan cannot be changed once approved export generates a final report that includes the pre-operative and virtual plan and the required VAC Guide instrument kit for surgery postoperative or follow-up scans may be uploaded to enable direct visual comparison between preoperative and postoperative situation Anatomy Osteology first metatarsal and medial cuneiform form the first TMT joint targeted in Lapidus arthrodesis sesamoid apparatus under the first metatarsal head is a key driver of hallux valgus deformity and rotational malalignment assessment second metatarsal and intercuneiform space are at risk during wire placement and saw cuts based on intraoperative fluoroscopic trajectories Muscles tibialis anterior insertion on the medial cuneiform and first metatarsal base influences first ray position and dorsiflexion forces peroneus longus plantar course supports first ray plantarflexion and can affect sagittal plane balance after fusion extensor hallucis longus is a landmark for dorsomedial incision planning Ligaments first TMT capsuloligamentous complex and plantar structures contribute to stability and fusion surface containment lateral capsular and lateral sesamoidal ligament contractures can contribute to persistent sesamoid subluxation after bony correction Nerves dorsal medial cutaneous nerve branches are at risk with dorsomedial approach and should be protected deep peroneal nerve region is relevant dorsally near the first web space and dorsum during instrumentation Approach Dorsomedial incision is created approximately 20 degrees from direct dorsal and medial to the extensor hallucis longus Incision length is described as 3 to 4 cm Skin incision is retracted laterally A small direct dorsal stab incision is made into the TMT joint capsule to expose access to the joint Stab incision size is described as just large enough to fit the paddle of the Joint Seeking Pin Guide Joint capsule is not fully exposed or mobilized and an osteotome is not placed into the joint, keeping the joint space tight Technique Device-specific workflow pre-op imaging to planning obtain and upload CT or X-ray imaging per software requirements review AI-identified landmarks, adjust as needed, and approve the analysis review virtual deformity correction, adjust IM and FP correction as desired, and approve the plan confirm the VAC Guide instrument kit recommended by the software and approved by the surgeon is available for the procedure joint seeking pin placement attach Joint Seeking Pin Guide to a Universal Handle and place into the TMT joint through the dorsal stab incision insert the Joint Seeking Pin through the guide in a direct dorsal orientation until apposing the plantar cortex using a wire driver or mallet verify on AP and lateral fluoroscopy that the Joint Seeking Pin is centered on the joint VAC Guide placement and wire insertion assemble the distal insert into the VAC Guide with orientation markings for side and proximal direction slide the VAC Guide over the Joint Seeking Pin through the central hole until in apposition with the foot pivot the guide around the pin until the proximal portion is central over the cuneiform place four 2.0 mm wires in the sequence described for cuneiform and metatarsal using a combination of short and long wires to reduce skiving and trajectory alteration confirm under fluoroscopy that all four wires have bicortical placement before proceeding remove the distal insert, then remove the Joint Seeking Pin and VAC Guide bone resections using the cut guide dissect the joint capsule to expose the joint without mobilizing the joint place the cut guide over the metatarsal wires through the holes marked 0 and resect the metatarsal using a long sawblade place the cut guide on the proximal wires and resect the cuneiform while keeping all wires fixated if additional resection is needed, use the re-cut slot marked 1 to make an additional cut on either surface avoid sawblade position and angulation that risks cutting the second metatarsal joint preparation distract the joint using a Hintermann retractor placed over the central wires remove bony wafers created during resections fenestrate joint surfaces with preferred technique and assess the clinical need for additional soft-tissue releases prior to proceeding realignment and compression using the RAC block start with the 0 RAC block and align the four dorsal holes over the four dorsal wires slide the RAC block over all four wires to compress the joint space and generate correction and alignment apply plantar counter-pressure during RAC block placement to reduce undesired plantar translation of the metatarsal verify desired correction by assessing IM and FP angles under fluoroscopy if additional frontal plane rotation is desired, use RAC blocks with 5 or 10 degrees of additional rotation if sagittal translation is desired, translate and hold the metatarsal plantarly while finalizing RAC block placement and confirm sagittal alignment verify compression under AP and lateral fluoroscopy by confirming apposition of joint surfaces if additional compression is needed, replace the 0 RAC block with a 1 or 2 RAC block to increase compression until apposition is achieved optionally place oblique wires through the RAC block to maintain alignment if removing the RAC block and the other four wires to reduce implant interference additional intermetatarsal angle correction (optional) remove the RAC block and cuneiform wires, then place the wire guide over the metatarsal wires and insert the joystick handle make a small incision between the necks of the second and third metatarsals and insert the DynaBunion IM radiolucent reducer secure the reducer to the first metatarsal head, use the joystick to rotate sesamoids into alignment, and place a short wire through the reducer into the first metatarsal head close down the IM angle using the reducer to the desired correction, then reinsert cuneiform wires through the wire guide perform an additional cuneiform resection using the cut guide as described and continue with RAC block placement fixation with implants implants are not part of the VIRTUGUIDE™ System VIRTUGUIDE™ instruments are described as compatible with a range of Lapidus fixation options General Lapidus and hallux valgus concepts hallux valgus deformity is commonly multiplanar, including intermetatarsal angle, hallux valgus angle, and first metatarsal pronation with sesamoid subluxation triplanar correction concepts emphasize frontal plane rotation control in addition to transverse plane correction Lapidus arthrodesis targets first TMT stability and alignment, aiming to restore first ray position and reduce recurrence drivers postoperative fusion success depends on joint preparation, compression, fixation strategy, and patient adherence to weight-bearing restrictions Technical specifications Software and imaging parameters software is configured to accept weight bearing CT scans and AP X-rays of the entire foot weight bearing imaging may influence deformed anatomy and may provide more accurate analysis of deformity correction needed CT requirements include DICOM format, slice thickness less than 1.25 mm, slice spacing less than 1.0 mm, pixel spacing less than 0.9 mm, and per-instance resolution at least 320 by 320 with all axial slices X-ray requirements include AP entire foot, DICOM modality DX or CR, pixel spacing less than 0.9 mm, and per-instance resolution at least 512 by 512 X-ray calibration using scaling factors enables AI-automated measurements in mm, and default magnification eliminates mm display VAC Guide patient-matched to deformity and incorporates IM and FP angles for wire placement in correction-specific positions 3D printed and supplied sterile packed single patient use only and must never be reused instrument kits are available as left- and right-foot options across multiple IM and frontal plane angle combinations Disposable and reusable instrumentation patient-matched VAC guide 2.0 mm K-wires with trocar in 102 mm and 152 mm lengths long sawblade Joint Seeking Pin reusable instruments include the Joint Seeking Pin Guide, cut guide, Universal Handle, and RAC blocks, supplied via a modular tray system Cut guide bone resection metrics cut guide position 0 is described to remove between 0.9 and 2.1 mm of metatarsal and cuneiform bone depending on distraction re-cut slot position 1 is described to remove an additional 1.5 mm of bone RAC block options 0, 1, and 2 levels of compression 0, 5, and 10 degrees of additional frontal plane rotation, with left, right, and universal configurations depending on the block Implants and screw options shown with fixation implants shown are described as potential Lapidus fixation options and are not components of the VIRTUGUIDE™ System cannulated compression headless screw options are shown across multiple diameters and lengths, with short- and long-thread configurations described by proportion of total length device-specific implant materials, compatibility details, and full fixation construct recommendations: not specified in provided manufacturer materials Pearls & Pitfalls Pearls ensure imaging meets CT or X-ray requirements and calibrate X-rays before analysis to enable mm-based measurements when available review AI-generated landmarks and adjust as needed before approving the plan, recognizing clinical assessment is necessary for proper system use confirm the recommended VAC guide instrument kit and required sterile disposable items are available prior to the case verify the joint seeking pin is centered on the joint on AP and lateral fluoroscopy before proceeding ensure VAC guide positioning is central over the cuneiform and avoid proximal wire holes that are too close to the intercuneiform space confirm bicortical placement of all four wires under fluoroscopy prior to bone cuts use a combination of short and long wires to reduce wire skiving and trajectory alteration from adjacent wires apply plantar counter-pressure during RAC block placement to reduce undesired plantar translation and confirm sagittal plane alignment verify correction of IM and FP angles and confirm compression with joint apposition under fluoroscopy consider RAC block rotation and compression options when additional correction or compression is required, and consider optional oblique wires if wire removal is needed to reduce implant interference Pitfalls using suboptimal imaging quality or imaging with metallic artifacts may reduce analysis quality and deformity correction planning failing to calibrate X-rays or relying on default magnification may limit mm-based measurements placing the joint seeking pin off-center can propagate alignment errors through guide placement and wire trajectories allowing wires to skive, remain unicortical, or drift due to crowding can compromise accuracy and stability during resection and compression inadequate sawblade control can risk iatrogenic injury to adjacent structures, including the second metatarsal failing to apply plantar counter-pressure during RAC block placement can lead to undesired plantar translation of the metatarsal proceeding without confirming correction and compression fluoroscopically can result in residual deformity or insufficient joint apposition reusing the VAC guide kit is contraindicated by device handling instructions