STABLYX ® Surgical Approach

STABLYX ® Surgical Approach

  • 1. EXPOSURE
    Make a 4cm incision centered
    over the carpometacarpal
    (CMC) joint along the course
    of the extensor pollicis brevis
    (EPB) tendon.

  • 2. EPB TENDON RELEASE
    Dissect to expose and
    release the EPB tendon
    proximal and distal, then
    retract it ulnarly.

    Note: Be sure to protect the radial
    artery, as well as the lateral
    and dorsal branches of the
    radial nerve.

  • 3. CAPSULOTOMY
    Elevate the joint capsule
    as an ulnar based flap
    and release ligaments
    circumferentially.

  • 4. APL TENDON RELEASE
    Partially release the proximal
    part of the insertion of the
    abductor pollicis longus
    (APL) tendon to allow full
    access to the base of the
    metacarpal.

  • 5. METACARPAL RESECTION
    Secure the metacarpal with
    the bone holding forceps.

    Resect the base of the
    metacarpal just distal to
    the articular surface and
    perpendicular to the axis of
    the metacarpal.

  • 6. ACCESSING THE VOLAR CAPSULE
    Expose the joint, then
    remove excessive synovium
    and resect osteophytes from
    the metacarpal.

  • 7. LOCATING PALMAR OSTEOPHYTE
    A palmar osteophyte on
    the trapezium prevents joint
    reduction in osteoarthritic
    patients.

    Using the Capsular Elevator,
    release the volar capsule
    from the trapezium to
    expose this osteophyte.

  • 8. REMOVAL OF PALMAR OSTEOPHYTE
    The FCR tendon is found
    beneath the palmar
    osteophyte.

    Using the Curved
    Osteotome, remove
    the bulk of the offending
    palmar osteophyte.

  • 9. TRAPEZIOPLASTY
    Insert the Trapezial Rasp
    between the FCR tendon
    and the trapezium.

    Rasp the central aspect of
    the trapezium into a saddle
    shape.

    Note: The Capsular Elevator
    should be used as a probe
    to confirm the palmar
    osteophyte has been
    removed.

  • 10. TRAPEZIOPLASTY
    Insert the Trapezial
    Contouring Tool between
    the FCR tendon and
    trapezium.

    Complete the final
    contouring of the trapezium
    into a smooth saddle shape
    using an oscillating rotary
    motion.

    Occasionally in a severely
    deformed trapezium, the
    use of a small curette or burr
    may be useful.

  • 11. TRAPEZIAL SIZING
    Determine the size of the
    trapezium by positioning
    the Trapezial Sizing Tool
    over the midpoint of the
    trapezium.

    The correct sizing is achieved
    when the Trapezial Sizing Tool:

    A. Loosely fits to allow 1mm of
    translation in the AP direction.

    B. Can fit across the width of
    the trapezium.

  • 12. SURROUNDING OSTEOPHYTE REMOVAL
    Remove any remaining
    motion restricting
    dorsal, medial or lateral
    osteophytes.

  • 13. METACARPAL CANAL PREPARATION
    The system includes five
    Metacarpal Reamers that
    corresponds to each of the
    Trapezial Sizing Tools.

    Attempt to ream up to the
    corresponding Trapezial
    Sizing Tool selected in
    Step 11.

    If unable to ream to the
    corresponding trapezial size,
    additional trapezioplasty
    may be required.

  • 14. ESTABLISHING METACARPAL ROTATION
    To establish the correct
    rotational alignment, use a
    STABLYX® trial one size smaller
    as it will freely rotate within the
    intramedullary canal.

    A. Place the thumb in full
    opposition by opposing the
    thumb to the small finger and
    mark the location of the tab.

    B. Now place the thumb in
    full radial abduction and
    mark the location of the
    tab. Identify the rotational
    midpoint.

  • 15. TRIAL REDUCTION
    Replace the undersized trial
    with the appropriate size.

    Confirm that the proper
    clearance for the volar
    lip has been achieved by
    placing the CMC joint in full
    opposition and observing
    that hinging does not occur.

    When reducing the CMC
    joint, be sure to avoid injury
    to the trapezial surface
    by using the back of the
    Capsular Elevator.

  • 16. TRIAL FLUOROSCOPY
    Under fluoroscopy, articulate
    the joint through its full range
    of motion to confirm proper
    alignment and kinematics.

    Confirm that all offending
    osteophytes have been
    removed and that proper
    clearance for the volar lip
    of the implant has been
    achieved.

  • 17. SUTURE STABILIZATION
    The STABLYX® prosthesis
    provides suture holes for
    attachment to the FCR
    tendon. This provides
    temporary stabilization
    during the early healing
    process.

    Pass an absorbable suture
    through the FCR tendon at
    the midpoint of the trapezial
    surface.

    Pass each lead of the suture
    through the corresponding
    hole of the prosthesis.

  • 18. ROTATIONAL ALIGNMENT
    Rotational alignment of the
    prosthesis should correspond
    to the previously marked
    rotational midpoint.

    A. Align the etched mark of
    the prosthesis to the marked
    rotational midpoint on the
    metacarpal.

    B. Now insert the prosthesis
    until the keel firmly engages
    cancellous bone.

  • 19. PROSTHETIC SEATING
    Pull the suture lines taut, then
    use the Impactor to fully seat
    the prosthesis.

  • 20. CLOSING THE CAPSULE
    Confirm that the FCR tendon
    is not interposed within the
    CMC joint.

    Tie the suture over the
    prosthesis creating a
    suspensionplasty.

  • 21. IMPLANT VALIDATION
    Manipulate the joint through
    its full range of motion to
    confirm implant stability and
    proper kinematics.

  • 22. DORSAL CAPSULE REPAIR
    Suture back the ulnar based
    capsular flap to the APL
    tendon.

    Optional: Pass the FCR suture leads
    through the repaired flap
    and tie them over the dorsal
    capsule.

  • 23. FINAL FLUOROSCOPY
    Confirm proper implant
    placement using
    fluoroscopic imaging.

    Close the incision in your
    usual fashion.

  • 24. POST-OP MANAGEMENT
    Support the thumb in a splint
    for 3-4 weeks, then allow
    functional use.