Two-stage arthrodesis for complex, failed, infected total knee arthroplasty.

Area of Science:

• Orthopedic Surgery
• Infectious Diseases
• Biomaterials Science

Background:

• Chronic infection following total knee arthroplasty (TKA) presents a significant challenge, with limited salvage options.
• Arthrodesis is an infrequently utilized salvage procedure for infected TKA, lacking extensive outcome data.
• Complex TKA infections often involve extensor mechanism deficiency and require advanced reconstructive techniques.

Purpose of the Study:

• To evaluate the reliability, durability, and safety of knee arthrodesis as a definitive treatment for complex, chronically infected TKA.
• To assess the long-term outcomes of a two-stage knee arthrodesis protocol in a contemporary patient cohort.

Main Methods:

• Retrospective analysis of 41 patients undergoing two-stage knee arthrodesis for complex infected TKA between 2002 and 2016.
• Detailed patient demographics, including age, BMI, extensor mechanism status, and host/limb classification.
• Characterization of infection type (polymicrobial, multi-drug resistant) and fixation methods (intramedullary nail, external fixator, dual plates).

Main Results:

• Five-year survivorship free from amputation was 95%; free from persistent infection was 85%; free from reoperation was 64%.
• Reoperation occurred in 32% of patients; radiological nonunion developed in 24%, significantly correlated with persistent infection and external fixation.
• Among successfully salvaged limbs, 87% of patients remained mobile with 79% reporting minimal or no pain.

Conclusions:

• Two-stage knee arthrodesis provides high amputation-free survival (95%) and good functional mobility (87%) for complex infected TKA.
• High rates of early reoperation (32%) and nonunion (24%) were observed, reflecting the severity of the included patient population.
• This salvage procedure is a viable option for 'worst-case' infected TKA scenarios, despite the associated surgical challenges.