Floating Knee Arthrodesis After Periprosthetic Knee Infection: A Multi-Center Study

Area of Science:

• Orthopedic Surgery
• Infectious Diseases
• Arthroplasty

Background:

• Periprosthetic joint infection (PJI) of the knee often necessitates salvage procedures.
• Knee arthrodesis offers an alternative to above-knee amputation in managing complex knee PJIs.

Purpose of the Study:

• To analyze the outcomes of floating knee arthrodesis in patients with a history of PJI.
• To externally validate the Baeza-Ortega scale for functional assessment in this patient cohort.

Main Methods:

• Retrospective study of 86 patients undergoing floating knee arthrodesis for PJI between 2012-2022.
• Data collected from three Spanish referral centers for complex bone and joint infections.
• Clinical, analytical, radiographic, and functional assessments using the Baeza-Ortega scale.

Main Results:

• 15% reinfection rate and 29% complication rate observed at a mean 4-year follow-up.
• McPherson Limb Grade 3 was associated with a higher reinfection risk (P=0.036).
• 53% of patients achieved excellent or acceptable functional outcomes, with a significant correlation between satisfaction and function (P=0.0006).

Conclusions:

• Floating knee arthrodesis is an effective and safe procedure for managing recurrent PJI when knee prosthesis revision is not feasible.
• The procedure provides satisfactory functional results and avoids amputation.