47 Salto Talaris Total Ankle Replacement Abstract The Salto Talaris total ankle replacement is a fixed-bearing implant used to treat end-stage ankle arthritis with the goals of providing pain relief, restoring mechanical alignment, and allowing motion of the ankle joint. This chapter aims to describe the operative technique of the Salto Talaris total ankle replacement with step-by-step instructions for the procedure, as well as pearls for implantation and tips to optimize outcomes and limit complications. This chapter also highlights preoperative preparation, hazards and pitfalls of the operation, salvage options, and postoperative care. Keywords: Salto Talaris, total ankle replacement, total ankle arthroplasty, ankle arthritis, posttraumatic ankle arthritis, ankle osteoarthritis, fixed bearing, technique guide • This procedure is reserved for end-stage tibiotalar degeneration secondary to osteoarthritis, posttraumatic arthritis, or inflammatory arthritis. • A thorough preoperative assessment is performed to include a history of prior trauma to the ankle or other less common etiologies such as inflammatory arthropathy, gout, or infection. A detailed physical examination is performed that includes gait analysis, range of motion of the ankle and hindfoot, and a neurovascular examination. It is especially important to take note of previous ankle operations, the quality of the soft tissues, and overall alignment of the ankle and foot. This is critical for planning of potential adjunctive procedures such as hardware removal, ligament balancing, equinus correction, or reconstructive procedures (osteotomies and tendon transfers).1–3 • Patients are evaluated with a complete series of weight-bearing ankle and foot radiographs to evaluate the extent of their arthrosis, predict component sizing, check talar dome shape, and plan for potential adjunctive procedures, particularly hardware removal or reconstructive procedures requiring deformity correction.1 • Advanced imaging with computed tomography (CT) can be useful to evaluate patients with questionable bone stock or to evaluate cystic lesions. • Activity modification. • Physical therapy. • Nonsteroidal anti-inflammatory drugs (NSAIDs). • Shoe wear modification with a rocker-bottom. • Bracing with an ankle–foot orthosis for mechanical unloading. • Cortisone injections. • Active ankle joint infection or osteomyelitis of the surrounding bone. • Inadequate soft-tissue envelope. • Morbid obesity. • Inadequate bone stock. • Severe deformity. • Patient preference for ankle arthrodesis. • Loss of protective sensation/neuro-arthropathy. • Osteonecrosis. • Severe vascular disease. • To provide pain relief with restoration of the mechanical alignment and soft-tissue stability of the ankle joint. • Potential to maintain or restore ankle joint motion. • Avoidance of nonunion risk with ankle arthrodesis. • Improved gait kinematics compared to arthrodesis. • Avoidance or reduction of adjacent joint disease. • Diligent preoperative planning to identify and avoid potential pitfalls. This involves being prepared for potential adjunctive procedures to correct alignment and provide stability to the ankle. • Meticulous soft-tissue handling. • Minimal bone resections to provide compact bone for impaction of implants and to conserve bone stock. • Be familiar with the instrumentation to ensure efficient and reproducible results. We do not routinely template preoperatively, and this is why: We tend to intentionally undersize the initial tibial cut (using a size 1 or 0 cutting block) in order to not cut too much malleoli at the outset. The final determination of tibial implant size will ultimately be determined during implant trialing using a lateral fluoroscopic image to verify coverage in the anterior to posterior dimension. We feel it is critical to ensure adequate implant coverage in this plane so that the tibial baseplate has adequate support on the posterior cortex. If upsizing is necessary at this point, it is then easy to gradually increase the medial to lateral width with the reciprocating saw as needed. For the talus, it is the same initial cutting guides for the 1, 2, and 3 talar prostheses. This means that typically the final decision for implant size does not need to be made until after the initial cuts. Additionally, it is imperative to take into account whether an ankle is “tight” or “loose,” which will be in intraoperative finding. A looser ankle demands less bony resection (in the superior-to-inferior plane) and thus often results in a smaller talar component. This protocol allows us to make intraoperative decisions that best fit the patient, for both the tibia and the talus. • This procedure is performed under a regional take-home anesthetic block and/or general anesthesia with preoperative antibiotics. The regional anesthetic is typically an indwelling popliteal catheter with a single-shot saphenous block. • Supine, foot positioned at the end of a radiolucent table. • Bump under the operative hip to place the foot in a neutral position and prevent external rotation. Fig. 47.1 Placement of the external alignment guide. Note how to control resection level (set screw A), mediolateral orientation (set screw B), and rotation (set screw C) with guide. • Thigh tourniquet recommended. • Large C-arm fluoroscopy used, brought in perpendicular to the table from the operative side. • Stack of towels or custom bone foam under the operative ankle is optional. This elevates the operative extremity above the contralateral extremity to aid with imaging. • A 10to 12-cm longitudinal, midline incision is marked out. It starts a fingerbreadth lateral to the tibial crest and extends longitudinally toward the second web space. • Incise through skin. Find and protect the superficial peroneal nerve, resting just above the fascia. Retract the nerve laterally. • Incise the extensor retinaculum and divide longitudinally over the extensor hallucis longus (EHL) sheath. The EHL is retracted lateral and the tibialis anterior is kept within its sheath and retracted medially. The neurovascular bundle will be seen laterally under the EHL. Once the bundle is safely identified and protected, incise straight down to bone on the medial side of the bundle. There are always crossing veins, which should be cauterized. Raise medial and lateral subperiosteal flaps proximally and distally. • Incise the anterior ankle joint capsule longitudinally and reflect the capsule and subperiosteal flaps up until both the medial and lateral gutters are accessible. Place a deep self-retaining retractor at the level of the ankle joint. • This guide (Fig. 47.1) should be placed parallel to the tibia’s mechanical axis and in neutral rotation to the ankle joint.4 A pin is placed in the tibial tubercle to secure the guide proximally. Make a small incision over the tubercle. Predrill and place the pin. • Place the alignment guide over the tubercle pin in the neutral hole with about two fingers between the guide and tibial tubercle. Distally the guide should rest flush to the tibia at the level of the plafond. The guide should also be roughly aligned centrally within the plafond in the medial to lateral plane. Have the height adjustment set initially at 15 mm (position zero) to allow for translation proximally in a few steps. • Stabilize the guide distally with a pin through the distal, medial hole (the guide should be positioned in the center of the metaphysis). • Use intraoperative fluoroscopy and direct inspection to determine the appropriate alignment, tibial component size, and resection level as guided by the external tibial alignment and cutting guides (Fig. 47.2). • Varus/valgus alignment: With the distal end of the guide at the level of the plafond, check an anteroposterior (AP) image to confirm that the resection will be perpendicular to the mechanical axis of the tibia. If a change needs to be made, move the guide on its proximal pinholes. Fig. 47.2 Fluoroscopic image used for sizing confirmation of the cutting block. • Resection level: The minimal recommended resection level is 9 mm (accounts for the composite thickness of the tibial plate and the lowest thickness of polyethylene [PE]). Use set screw A to translate the guide proximally from the level of the plafond to the desired resection level (if the guide was set at position zero, this will allow for up to 15 mm of translation). Tighten screw A to lock in the height of your cut. • Rotation: The goal is to have the alignment guide set at the bisection of the malleoli. Place the rotational jig on the distal end of the alignment guide and place a pin through the articulating arm. With the ankle in neutral position, check that the pin is aligned with the second ray. Confirm that set screw C is tightened to lock in rotation. • Medial to lateral alignment: Translate the alignment guide so that it aligns over the axilla of the medial malleolus. The rotational jig also has a series of medial and lateral holes that correspond to the available implant sizes (0, 1, 2, and 3). Tighten set screw B to lock in the mediolateral position once satisfied with position. • Place the cutting block on the alignment guide. The cutting block size should correspond to preoperative planning and the size confirmed by the last step. • Lateral slope: The alignment guide should be parallel to the anterior tibial slope on a lateral image. If a change in the slope needs to be made, raise or lower the guide on its proximal pin. • Once satisfactory position of the cutting guide is obtained, drill and fill the top medial and lateral holes in the cutting guide and mallet pins down to level of guide (protects malleoli from the sweep of the saw). Drill the remaining four distal holes bicortically to prepare the vertical cuts (drill holes but do not place pins). • Confirm that all set screws are tightened and perform the horizontal tibial cut with an oscillating saw, carefully avoiding penetration deep to the posterior tibial cortex. Slide the cutting block off. Complete the vertical cuts with a small osteotome or reciprocating saw. Remove the distal tibial segment. • The talar pin setting guide is placed on the distal end of the alignment guide. Maintain the ankle in neutral dorsiflexion and the foot in neutral rotation during pin placement. Predrill and place a pin in the hole (Fig. 47.3). • Place the appropriately sized talar dome resection guide over the talar pin. There is a guide for size 0 and one for sizes 1, 2, and 3. Use the largest size that will not impinge on either malleolus (Fig. 47.4). • The paddles on the resection guide must be flush with the dome of the talus. Confirm with a lateral fluoroscopic image. Drill and place four pins through the resection guide. Each pin should exit at the posterior articular surface of the talar dome. • The four pins define the upper plane of the talar cut. Remove the talar dome resection guide from the pins. Place ribbon retractors next to each malleoli to protect from the sweep of the saw blade. Make the talar dome resection with an oscillating saw, cutting flush on the top of the four pins (Fig. 47.5). • Remove all osteophytes from the talar neck with a rongeur. Place the anterior talar chamfer guide (with the talar position spacer inserted in the chamfer guide’s oblong window) on to the cut surface of the talar dome. The foot and ankle should be positioned at neutral dorsiflexion and neutral rotation, and the handle to the guide should be appropriately aligned down the second ray for correct rotation. Confirm positioning with a lateral fluoroscopic image. The anterior tibial cortex should be co-linear with the calibration line on the talar position spacer and the chamfer guide should rest flush on the cut surface of the talar dome. Once appropriately positioned, drill and pin the chamfer guide in place.
47.1 Indications and Pathology
47.1.1 Clinical Evaluation
47.1.2 Radiographic Evaluation
47.1.3 Nonoperative Options
47.1.4 Contraindications1–3
47.2 Goals of Surgical Procedure
47.3 Advantages of Surgical Procedure
47.4 Key Principles
47.5 Preoperative Preparation and Patient Positioning
47.5.1 Templating
47.5.2 Anesthesia
47.5.3 Positioning
47.6 Operative Technique
47.6.1 Exposure: Anterior Approach to the Ankle Joint
47.6.2 Placement of Tibial Alignment Guide
47.6.3 Adjustments of the Alignment Guide
47.6.4 Cutting the Tibia
47.6.5 Talar Pin Placement
47.6.6 Posterior Talus Resection
Remember that the final talar component MUST be the same size as the tibial component or one size less.
47.6.7 Anterior Talar Chamfer Resection
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