Invisible on X-ray
Anatomical Shape with Lock-in Flanges
Biocompatible, PEEK Radiolucence (invisible on X-ray)
X-ray Markers for Placement Confirmation
PitStop®
Subtalar Implant
The Implant is made of PEEK. This biocompatible and inert polymer is flexible, which allows for placement in the sinus tarsi with better load distribution on bone surfaces versus stiffer materials such as titanium and stainless steel.
The PitStop® Subtalar Implant facilitates the correction of pes plano valgus deformities.
X-RAY MARKERS
Two X-ray markers made of tantalum are located at each end of the implant to help guide the positioning of the implant.
LOCK-IN FLANGES
Lock-in flanges (small blades) are designed to provide primary stability in the sinus tarsi.
ANATOMICAL SHAPE
The anatomical shape, with the two symmetrical and flattened sides, is designed to reduce the compressive constraints and to improve distribution of stress. This may help to decrease incidence of reactive synovitis and improve patient tolerance.
CANNULATED IMPLANT
The PitStop is cannulated to facilitate and secure accurate positioning of the implant over a Guide Wire.
IMPLANT-INSTRUMENT ASSEMBLY
The easy keyed insertion device allows for a tight assembly between the implant and the instrument.
Surgical Technique
INCISION
A 1-3 cm incision is made on the lateral side of the foot in the skin overlying the sinus tarsi.
Blunt dissection with a hemostat to the level of the joint capsule.
OPTIONAL USE OF VILADOT’S LEVER
The Viladot’s Lever is introduced through the sinus tarsi. Move the lever slightly dorsal / medial and anterior / posterior to dilate the tarsal canal.
GUIDE WIRE INTRODUCTION
Once the talus is positioned on the calcaneus, the 1.6mm Guide Wire is introduced into the axis of the sinus tarsi until the wire is felt on the medial aspect of the hindfoot. Accurate placement may be confirmed with fluoroscopy.
INSERTER* / HOLDER PREP FOR TRIALS
Fig. A. Insert the Internal Holder through the base of the External Holder
Fig. B Then attach the Trial Implant to the end of the External Holder by aligning the pins of the Holder with the holes of the Trial Implant. The flat sides of the Trial Implant and the Inserter handle are aligned.
Fig. C Next, screw the Internal Holder through the External Holder into the Trial Implant and tighten.
TRIAL SIZER
The first Trial Implant is placed over the Guide Wire and seated in the sinus tarsi. Hindfoot mobility is assessed, and the size may be adjusted accordingly. Correct position of the Trial Implant may be verified by fluoroscopy. It is recommended to advance the leading edge of the Trial Implant close to but not past the talonavicular bisection on the AP view. The corresponding flat surfaces of the Trial and Inserter handle are aligned parallel to the lateral talar process, which is an approximately 45° angle to the fibula and the plantar aspect of the foot on the lateral view.
The Trial Implant is removed, leaving the Guide-wire in place.
INSERTER PREPARATION FOR IMPLANT
Fig. D As with the trial, the Implant is fixed to the External Holder.
Fig. E Then the implant is tightened onto the Internal Holder by turning the bottom knob to engage the Implant.
CANNULATED INSERTION
The Inserter is used to press fit the Implant in the correct position with a pushing motion. Do not screw Implant into place. X-ray markers at each end of the Implant help achieve the adequate depth with fluoroscopy visualization. The corresponding flat surfaces of the Implant and Inserter handle are aligned parallel to the lateral talar process, which is an approximate 45° angle to the fibula and the plantar aspect of the foot on the lateral view.
Unscrew the Internal Holder to release the Implant and push with finger pressure to remove the Holder from the Implant.
Hindfoot mobility is assessed to verify adequate correction. The wound should be closed according to surgeon preference.
