Outcomes of Transfemoral Osseointegration for Patients With Prior Amputation to Manage Infected Total Knee Arthroplasty.

Background: Management of total knee arthroplasty (TKA) periprosthetic joint infection (PJI) can prompt knee fusion or transfemoral amputation, both associated with poor mobility. The titanium transcutaneous osseointegrated nail (TiTON) provides superior mobility versus traditional socket prostheses but has been minimally studied for amputees with prior TKA PJI. Purpose: This study investigated the complications and mobility experience of 9 transfemoral osseointegration patients whose initial amputation was for TKA PJI management. Methods: A retrospective review of a prospectively maintained registry was conducted of 9 patients whose unilateral transfemoral osseointegration was performed following TKA PJI. Complications associated with the implantation of the titanium implant were noted, specifically antibiotic prescription or any additional surgery. K-level mobility performance before and after osseointegration was also compared. Results: Three patients (33.3%) had management for an infectious concern: 2 had a 10-day course of oral doxycycline for periportal drainage, and 1 had operative debridement with implant retention. No other complications (periprosthetic fracture, implant removal, and additional amputation) occurred. Eight patients (88.9%) improved their K-level, while 1 remained at K3. None declined. All achieved at least K2. Three patients were wheelchair-bound (K0) before osseointegration and achieved K3 or better. Conclusions: While infection may occur in patients who have TiTON following TKA PJI, our findings suggest that it does not seem inevitable, severe, or likely to further disable the patient. We noted meaningful mobility improvement that was common and lasting. Although our sample was small, we suggest that TiTON seems safe and reasonable to offer to patients seeking improved mobility and quality of life after amputation for TKA PJI management. Further study is warranted.