Motion Preservation in Hallux Rigidus After Failure of Hydrogel Implantation: Treatment Considerations and a Report of 2 Cases.

Hallux rigidus is a common condition treated daily by surgeons worldwide. During the past decade, the standard treatment algorithm has been questioned by both patients and surgeons seeking alternatives to arthrodesis, which was previously considered the gold standard for advanced disease. Patients are living longer, and many have a more active lifestyle; thus, recreating and improving range of motion and achieving pain relief are increasingly desirable. The treatment spectrum and implant options for motion-preserving techniques in the metatarsophalangeal joint has been widened with the recent US Food and Drug Administration approval of a polyvinyl-alcohol hydrogel implant. In the controlled US Food and Drug Administration trial, the 2-year revision rate was 9.2% and all failures were revised to a first metatarsophalangeal arthrodesis. Outcomes comparison of these revisions to primary fusions showed less predictable pain relief and may warrant alternative treatment considerations, preferably those that allow for continuation of motion preservation. Revision of failed hydrogel implants to arthrodesis can be performed through various first metatarsophalangeal fusion techniques or, as introduced in this review, with a fourth-generation threaded hemiarthroplasty. Excellent 10-year results with primary hemiarthroplasty supported its use as revision procedure in 2 failed polyvinyl-alcohol implantations, preserving arthrodesis for future salvage if necessary. The purpose of this report was to outline a motion-preserving technique after failed hydrogel implants and describe preoperative, intraoperative, and postoperative considerations for optimized outcomes.