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    Revision TKA: Tips and Tricks from the Experts

    Dr. Michael Ries and Dr. Christopher Peters share their top moves in the operating room when performing a revision total knee arthroplasty.

    At ICJR’s annual Winter Hip & Knee Course, 5 sessions was dedicated to the experts’ top move in performing primary and revision total knee (TKA) and total hip arthroplasty (THA).

    In this article, we focus on revision TKA, with tips and tricks from Michal D. Ries, MD, and Christopher L. Peters, MD

    Michael D. Ries, MD
    Tahoe Fracture and Orthopedic Medical Clinic, Carson City, Nevada

    Dr. Ries shared these top 5 moves in revision TKA with the meeting attendants:

    Use old incisions and raise a thick subcutaneous flap using subfascial dissection. Being aware of the blood circulation around the knee will help the surgeon pick the right incision, Dr. Ries said. The skin over the knee is supplied through the saphenous veins from medial to lateral. In addition, blood supply in the cross-sectional plane perforate from the muscle layer and go transversely in the subfascial plane, which is the reason Dr. Ries raises thick flaps using subfascial dissection.

    Remove the tibial insert as soon as possible and then debride the lateral gutter to mobilize the extensor mechanism. The key to a revision TKA is good exposure and mobilization. Dr. Ries accomplishes this by removing the tibial insert as soon as possible and then debriding the lateral gutter to mobilize the extensor mechanism.

    If an extensile exposure is necessary, use a “chevron cut” tibial tubercle osteotomy. If he can’t achieve good exposure using his standard arthrotomy, Dr. Ries prefers to proceed with a “chevron cut” tibial tubercle osteotomy (TTO). Dr. Ries reattaches the TTO using screw and wire fixation.

    Use distal and posterior femoral augments with a posteriorly offset stem instead of using a thicker polyethylene. In revision TKA, balancing is mainly achieved through component placement, Dr. Ries said. He uses distal and posterior augments combined with a posteriorly offset stem to move the femoral component distally and posteriorly, thereby balancing the gaps using a thinner polyethylene insert than would otherwise have been necessary.

    For severe patella Baja, shift the TTO proximally. if the knee still has severe patella Baja after proper component placement and gap balancing, Dr. Ries shifts the TTO proximally. Dr. Ries noted that the surgeon must be careful not to shift the TTO too far proximal, as the bone may then fracture and disrupt the extensor mechanism.

    Click the image below to watch his presentation.

    Christopher L. Peters, MD
    Department of Orthopaedics, University of Utah, Salt Lake City

    Dr. Peters finds the following 5 moves help him perform a successful revision TKA:

    Proper exposure. Dr. Peters believes that most complications related to revision TKA are caused by lack of good exposure, as good exposure is important for implant placement, postoperative function, and range of motion. He uses an extensile medial parapatellar arthrotomy with aggressive scar and synovium resection to mobilize the soft tissues, paying special attention to the extensor mechanism. For more difficult exposures, he uses a quadriceps snip, which he finds is sufficient for more than 90% of his cases.

    Component removal. The key to component removal is bone preservation, Dr. Peters said. He first uses an oscillating saw to cut the cement/bone interface, and then he uses a flexible osteotome to further separate bone and cement. Finally, Dr. Peters uses a handheld “footed” impactor to remove the components.

    Trial first technique. Dr. Peters noted that he rarely cuts any bone in a revision case. He also rarely uses standard cutting guides. Instead, he goes directly to component templates that are sized based on preoperative templating and the size of the previous implants.

    Offset cementless stems. In most cases, the stem determines the positioning and alignment of the components, Dr. Peters said, and in his hands, offset stems allow more accurate component placement. These stems can be used with or without cones and sleeves, depending on the amount of bone loss. Dr. Peters uses a hybrid cement technique with an uncemented metaphyseal stem.

    Use the least amount of constraint possible. Bearing choice is multi-factorial, Dr. Peters said. He evaluates each patient individually and chooses the bearing according to the amount of bone loss, the soft tissue integrity, and the patient’s activity level (low demand or high demand). He uses the least amount of constraint necessary, based on these factors. Dr. Peters, cautioned, however, that there are times where a hinge prosthesis is the right choice.

    Click the image below to watch his presentation.