[GMK rotating hinge prosthesis. A valid option for complex revision knee prosthetic surgery].

Abstract

Introduction: revision joint replacement surgery presents a surgical challenge. The use of rotating hinge prostheses is an option in patients with femorotibial bone defects, ligament insufficiency, or significant deformities. The aim of this study was to evaluate the clinical, functional, and radiological outcomes of a series of patients who underwent surgery using the GMK Hinge (Medacta®) rotational hinge model.

Material and methods: a descriptive, retrospective, and analytical study was conducted on a series of 36 patients, with a mean age of 72.5 years (47-85), operated on by the same surgical team between January 2015 and January 2022. The etiology of revision was chronic infection in 38.9% of cases, instability in 33.3%, aseptic loosening in 19.4%, and stiffness in 8.4%. The Knee Society Score (KSS) and the Forgotten Joint Score (FJS) were used to assess functional outcomes. The degree of femorotibial bone defect was evaluated using the Anderson Orthopaedic Research Institute (AORI) classification. Postoperative complications are also recorded.

Results: a total of 36 patients, 17 males and 19 females, were included, with a mean follow-up of 30 months (12-66). Twelve patients had type 1 defects, ten had 2A defects, ten had 2B defects, and two had type 3 defects on the femoral side, with the use of wedges required for asymmetrical defects (21 patients). The predominant tibial defect was type 1 without the need for wedges. The majority achieved a satisfactory outcome on the KSS scale (72.2 ± 9.4), with significant differences compared to the previous KSS (54.3 ± 8.9). A score of 31 (12-67) was also obtained on the FJS scale. Postoperative complications were present in 16.7% of patients.

Conclusions: complex prosthetic revision surgery using a rotating hinge prosthesis represents a suitable therapeutic option, yielding appropriate clinical and functional outcomes, albeit not without complications.