Pearls: Direct Visualization of Alignment Correction and Stabilization in Calcaneal Osteotomies

Surgeons often use radiographic assessment to aid in bone alignment and confirm screw placement for orthopaedic reconstructive procedures. Several studies have questioned the reliability and safety of fluoroscopic imaging to assess correct positioning of hardware and alignment, particularly in the foot and ankle [1-3, 5-7]. There is a simple technique that will allow direct visualization of guide pin placement allowing for accurate screw placement during calcaneal osteotomy, while also enabling the surgeon to quantify the bone displacement during commonly performed osteotomies of the calcaneus. This tip saves time and radiation exposure in the operating room while improving accuracy of screw placement due to direct visualization.

We often use medial displacement calcaneal osteotomy to correct a planovalgus foot deformity. A Dwyer osteotomy (closing wedge lateral calcaneal osteotomy or the lateral displacement calcaneal osteotomy variant) is used to correct a varus deformity of the hindfoot. These osteotomies are commonly performed through a lateral approach to the calcaneus where an oblique cut in the calcaneus is made [4]. If it is needed for visualization, or to aid in stretching the soft tissues allowing for mobility of the bone, a laminar distractor can be temporarily inserted in the osteotomy. A guidewire from a 6.5 mm, 7.0 mm, or 7.3 mm screw set is placed at the posterior and plantar aspect of the calcaneus corresponding to the intended location for definitive fixation and advanced at an angle perpendicular to the bone cut until the tip is visualized within the osteotomy (Fig. 1). To quantify the amount of displacement, the guidewire can be advanced slightly to make a temporary “mark” in the superior bone and then backed up so the tip is just under the cut bone surface. A second parallel wire is commonly used for stability and placed in a similar fashion. The displacement of the osteotomy is easily made by using one guidewire as a joystick to move the calcaneal bone either medial or lateral and again, if needed, the guidewire can “mark” the superior bone to visualize and quantify the translation or distance between the two “marks”. When the displacement is judged appropriate under this direct visualization, the surgeon advances the guidewire into the superior calcaneus. The surgeon can feel confident of the osteotomy displacement and that the screws will be in the bone, saving radiation exposure and time. A single lateral view and Harris view can confirm the final positioning of screws. If lateral staples are used, the guidewire can be helpful for direct visualization of the corrective osteotomy and temporary fixation, followed by staple placement if preferred after which the guide pin is removed.

Fig. 1.

This figure shows the placement of the guidewire in the posterior-plantar heel with the tip visualized within the oblique osteotomy. The blue cylinder denotes the point in the bone marking the starting point prior to medial displacement of the calcaneus. This reference spot can be used to quantify the amount of translation of the bone prior to fixation. When the correction is completed, the guidewire is advanced safely as it is in appropriate position in the superior area of the calcaneus, verified by direct visualization.