Functional Outcome of Above-Knee Amputation After Infected Total Knee Arthroplasty

Background: Periprosthetic joint infection is a serious complication of total knee arthroplasty (TKA). Management usually involves irrigation and debridement, polyethylene liner exchange, one-stage revision, two-stage revision, knee arthrodesis, or ultimately above-knee amputation (AKA). We present our experience with 21 patients who underwent AKA as a sequela of unresolved infected TKA, highlighting their etiology and functional outcomes. Methods: A retrospective chart review was performed for all cases of infected TKA treated with AKA at 1 institute from January 2007 to December 2020, with a minimum follow-up of 1 year. Patient demographics, Charlson comorbidity index, culture results, ambulation status, prosthesis fitting, and functional outcomes were collected. Short Form-36 and activities of daily living questionnaires were used for functional outcome assessment. Results: Twenty-one patients were identified, 7 of whom were male (33.3%). Mean ± standard deviation follow-up was 5.7 ± 3.1 years (range, 1-11 years). Mean ± standard deviation age was 57.9 ± 10.7 years (range, 38-87 years), and the mean body mass index was 33.5 ± 6.4 kg/m2 (range, 25.4-46 kg/m2). Gram-positive organisms were identified in 15 cases (66.7%). Prosthesis fitting was successful in 17 patients (81%). Post-AKA ambulation was achieved in 12 patients (57.1%). The ambulating group showed higher Short Form-36 and activities of daily living scores when compared with patients who did not ambulate (60.2 vs 43.3, P = .041, and 67.2 vs 52.7, P = .029, respectively). Conclusions: AKA should be considered solely as the final recourse for infected TKA. Despite the low-to-moderate patient-reported postoperative outcomes, prosthesis fitting and maintaining ambulation can improve postoperative functional outcomes

Efficacy of Infection Eradication in Antibiotic Cement-Coated Intramedullary Nails for Fracture-Related Infections, Nonunions, and Fusions

Antibiotic cement-coated intramedullary nails (ACCINs) are increasing in popularity as a viable solution for the treatment of fracture-related infections (FRIs), infected long bone nonunions, and arthrodeses without an external fixator. ACCINs effectively manage to fulfill three of the basic principles for eradicating osteomyelitis: dead space management, antibiotic delivery, and bone stability. We performed a retrospective review of 111 patients who were treated with ACCINs between January 2014 and December 2020. In our series, 87.4% (n = 97) of patients achieved healed and uninfected bone or stable arthrodesis at a mean follow-up of 29.2 months (range, 6–93 months). Additionally, 69.1% (n = 67) of healed patients were resolved after only one procedure, and the remainder (30.9%, n = 30) healed after one or more additional procedures. The mean number of additional procedures was 2.1 (range, 1–6 additional procedures). The overall limb salvage rate was 93.7% (n = 104). The majority of the total cohort were successfully treated in only one surgery. This study suggests that ACCINs are effective in the treatment of FRIs, infected long bone nonunions, and infected ankle and knee arthrodeses

Tobramycin Blood Levels after Local Antibiotic Treatment of Bone and Soft Tissue Infection

Local antibiotic delivery using different carriers plays an important role in both infection prophylaxis and treatment. Besides dead space management, these carriers have the advantage of providing a high concentration of local antibiotics with a lower risk of systemic toxicity. Few studies have reported on systemic toxicity associated with antibiotic-impregnated carriers. The present study investigates the systemic tobramycin concentration at 24, 48 and 72 h postoperatively after using tobramycin-loaded polymethyl methacrylate (PMMA) and calcium sulfate (CS) as local antibiotic carriers. Additionally, this work assesses the renal function postoperatively for indications of acute kidney injury (AKI). Fifty-two patients were treated in 58 procedures with tobramycin and vancomycin-loaded PMMA, CS, or both. All systemic tobramycin levels were <2 mcg/mL at 72 h, and the resulting rate of AKI was 12% (7/58). In conclusion, local tobramycin antibiotic delivery using PMMA, CS, or both remains a safe and effective modality in the treatment of osteomyelitis as long as the surgeon is aware of its possible nephrotoxic effect