Functional Outcomes of Early Weight Bearing after Modified Kidner Procedure

Abstract

Category: Midfoot/Forefoot; Sports Introduction/Purpose: The Kidner procedure is performed to treat the symptomatic accessory navicular that has failed nonoperative treatment. Classically, the Kidner procedure involves excision of the accessory navicular with detachment and advancement of the posterior tibial tendon to the base of the navicular tuberosity. Various modifications of the Kidner procedure have been reported in the literature in which the accessory navicular is excised but without complete detachment of the PTT. Typically, the PTT is reinforced back to the navicular tuberosity insertion, usually with a suture anchor. The standard postoperative protocol includes non weightbearing for six weeks. Early weight bearing is gaining popularity in the foot and ankle community. No study to date has evaluated outcomes with early weight bearing after a Kidner procedure. Methods: This is a retrospective comparative study of 34 patients who underwent a Kidner procedure involving excision of the accessory navicular with detachment and reattachment of the posterior tibial tendon with suture or a suture anchor. Surgery was performed by two fellowship trained foot & ankle surgeons from a single institution. A total of 16 patients (17 feet) were included in the early weightbearing protocol group (2 weeks). A set of matched patients (n=17) with a similar age and surgical date were used as the control group with standard weight bearing at 6 weeks postoperative. Postoperative function and complications were obtained from a retrospective chart review of prospectively collected data until final follow up (mean, 18 weeks). This was a qualitative assessment specifically looking at whether early weight bearing led to increased complications and/or decreased function compared to standard weight bearing at six weeks. Results: Of the 34 total patients, there were no cases of postoperative posterior tibial tendon rupture or failure of the repair. In the early weight bearing group, there was one complication. This patient had a chronic flatfoot and developed a posterior tibial tendonitis at 6 months postoperative after returning to routine activity. This required boot immobilization and physical therapy. The standard weight bearing group had four complications. Two patients had posterior tibial tendon weakness and prolonged rehabilitation at 4 and 6 months postoperative. One patient had stiffness and pain at 6 months postoperative. And one patient developed a deep vein thrombosis at 3 weeks postoperative. Otherwise, all patients had returned to routine shoewear and resumed their normal activities, including sports, at final follow up. Conclusion: Early weight bearing after foot and ankle procedures is becoming increasingly popular. This study found that early weight bearing at 2 weeks postoperative after the Kidner procedure has no increased complication rates compared to standard weight bearing at 6 weeks postoperative. Based on the complications that occurred in the standard weight bearing group, early weight bearing may actually be protective against complications that occur with prolonged immobilization, such as weakness, stiffness, and deep vein thromboses.