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Rates of medial and/or lateral gutter impingement after total ankle replacement are not insignificant. If impingement should occur, it typically arises an average of 17 months after total ankle replacement. Our patient underwent treatment for right ankle medial gutter bony impingement with arthroscopic debridement 5 years after her initial total ankle replacement. Standard anteromedial and anterolateral portals and a 30° 2.7-mm-diameter arthroscope were used. An aggressive soft-tissue and bony resection was performed using a combination of curettes, a 3.5-mm shaver, a 5.5-mm unsheathed burr, a drill, and a radiofrequency ablator. This case shows that arthroscopic treatment is an effective and potentially advantageous alternative to open treatment of impingement after total ankle replacement. In addition, symptoms of impingement often improve in a short amount of time after arthroscopic debridement of the medial and/or lateral gutter.
Medial and lateral gutter ankle impingement may result after total ankle replacement (TAR). Impingement after TAR can be a source of pain and decreased patient satisfaction, which in turn results in poor outcomes.1 Impingement is of an unknown, complex etiology and is likely multifactorial. Often, nonoperative management is not successful in the setting of impingement after TAR; thus surgery is often pursued. This can be either open or arthroscopic. There is not much literature to support one treatment technique over the other, but both techniques have been shown to be safe and effective in treating the pain and disability associated with impingement after TAR. The patient in Video 1 underwent arthroscopic treatment of impingement after right TAR using the STAR device (Stryker, Kalamazoo, MI) for symptomatic medial gutter bony impingement. Preoperative anteroposterior, mortise, and lateral weight-bearing radiographs showed bone in the medial gutter with the prosthesis immediately adjacent to the medial malleolus (Fig 1).
The operation is performed with the patient under regional anesthesia in a supine position. A thigh tourniquet is placed. The operative extremity is prepared and draped in the standard sterile fashion. The leg is exsanguinated, and the thigh tourniquet is inflated to 300 mm Hg. Standard anteromedial and anterolateral ankle arthroscopy portals are created simultaneously, with care taken to avoid the intermediate branch of the superficial peroneal nerve (Video 1). We introduce an 18-gauge spinal needle to confirm positioning at the level of the joint. A hemostat is carefully directed to and through the joint capsule. Once intra-articular, an aggressive soft-tissue dissection is carried out with the hemostat and then the trocar to break up the adhesions and scar tissue that form within the joint. To perform a medial debridement, a 2.7-mm arthroscope (Henke Sass Wolf, Tuttlingen, Germany) is introduced into the anterolateral portal, and a 3.5-mm shaver (Stryker) is inserted through the anteromedial portal.
At first, it may be difficult to visualize the shaver because of the amount of scar tissue within the joint. To localize the shaver, we touch the shaver to the arthroscope and slide down in front of it to visualize the shaver cutting edge. Care should be taken to ensure that one is immediately adjacent to the talus when beginning the debridement. The hooded portion of the shaver is kept in contact with the prosthesis to prevent resecting too much talar bone and to prevent damage to the metal and polyethylene of the TAR implant. Scuffs and scratches on the metal prosthesis can potentially lead to abrasive or third-body wear of the polyethylene (Fig 2). The most effective way to remove soft tissue from the gutter and medial malleolus is with the use of a radiofrequency ablator (Smith & Nephew, London, England). This is far more effective than the shaver. Care must be taken not to be disoriented because the shaver reflection in the prosthesis can sometimes be disconcerting.
The radiofrequency ablation device is used in short bursts so as to not allow the intra-articular fluid to become too hot. A curette (OrthoMed, Tigard, OR) is alternatively used to scarify and loosen the soft tissue to make it easier for the shaver to remove the scar tissue. Once the anterior aspect of the medial gutter is visualized, the soft tissue in the gutter is excised or ablated until the medial malleolus and medial aspect of the talus and/or prosthesis are seen. Next, a 4.0-mm unguarded burr (Stryker) is used to burr away both the medial malleolus and prominence of the talus (Fig 3). One must take care to visualize what needs to be sculpted. Although the unguarded burr is more efficient, it is also more risky to the prosthesis. At any point, one may need to switch to a larger arthroscope such as a 4.0-mm 30° arthroscope typically used in knees for better visualization and increased flow.
Once the burr creates a shelf posteriorly, a 3.5-mm drill is used to penetrate the posterior shelf of bone (Fig 4). Under direct visualization, the shelf is penetrated in a linear vertical line. After this, the right-angled curette is used to break the bone between the drill holes (Fig 5). We believe a complete decompression requires that the posterior tibial tendon be visualized through the anterolateral viewing portal in the medial gutter (Fig 6) and the peroneal tendon if the lateral gutter is being debrided. Using the drill technique avoids having to bring the burr in direct contact with the posterior soft tissues.
Intraoperative fluoroscopy is used to verify adequate debridement of all areas of bony impingement. Pearls and pitfalls of using arthroscopy to debride medial or lateral gutter impingement are shown in Table 1. The incision sites are closed with an absorbable suture on the capsular tissue and a nylon suture on the skin. Postoperatively, the patient is placed into a Controlled Ankle Motion boot walker and allowed to bear weight immediately. At 2 weeks, the sutures are removed and the patient is allowed to perform range-of-motion activities. Two weeks later, the patient is transitioned to use of a normal shoe. Postoperative weight-bearing radiographs show increased space between the medial malleolus and talar components (Fig 7). It is not uncommon for patients to have no tenderness to palpation along the medial gutter at 6 months postoperatively.
Current survival rates for TAR at 2.8 to 3.7 years are 94% to 96%,2, 3, 4 and survival rates at 8.9 to 14 years are 45.6% to 88.7%.5, 6 However, good outcomes in these patients can be negatively affected by impingement. To prevent impingement, surgeons should (1) attain appropriate ligament balancing intraoperatively to prevent dynamic impingement; (2) insert the correct component size—paying particular attention not to overstuff the talar component, which may result in immediate impingement between the implant and medial/lateral malleoli; (3) perform adequate medial and lateral gutter debridement at the time of the index procedure; and (4) avoid undercorrection or overcorrection of coronal-plane deformity.
Despite these recommendations, impingement has been reported to occur in 6% to 45% of patients after TAR.7, 8, 9, 10 In addition, in a review of 478 patients, Schuberth et al.11 reported the following impingement rates with the following implants: 11% for INBONE (Wright Medical Group, Arlington, TN), 12% for Salto Talaris (Tornier, Amsterdam, Netherlands), and 4% for STAR, with an average time to debridement of 17 months.
Patients with impingement will often present with medial or lateral pain exacerbated by plantar flexion and/or dorsiflexion, subfibular pain, and/or pain with palpation over the medial or lateral gutter. Often, nonoperative treatment does not provide adequate relief for these patients, thereby necessitating operative intervention. Indications for operative intervention for ankle impingement after TAR include pain localized to the medial or lateral gutter, mechanical symptoms, and/or evidence of bony impingement on radiographs. Currently, there is no gold standard to manage patients with bony or soft-tissue impingement. Both open11 and arthroscopic1, 12 techniques have been described in the literature. There are several advantages of using arthroscopic treatment over open treatment (Table 2). At our institution, the decision to perform an arthroscopic versus open procedure is based on surgeon preference and whether additional surgery is required at the time of the impingement debridement. Specifically, we use the open technique when the polyethylene liner needs to be exchanged or when additional soft-tissue or bony work needs to be performed. This is because fluid extravasation from the arthroscopy can make associated procedures difficult because of swelling. We propose using arthroscopy whenever possible to allow patients to more quickly return to mobilization and weight bearing.
The authors report the following potential conflict of interest or source of funding: J.K.D. receives support from Stryker, Wright Medical, Tornier, Merck, Exactech, and Bio Pro.
The patient presented with right medial gutter bony ankle impingement 5 years after a STAR procedure. The patient was placed in a supine position, and standard medial and anterolateral viewing portals, as well as a 30° 2.7-mm-diameter arthroscope, were used. A combination of curettes, a 3.5-mm shaver, a 5.5-mm unsheathed burr, a drill, and a radiofrequency ablator were used to perform an aggressive soft-tissue and bony resection.