Aiming for anatomical femoral axis on the coronal plane leads to good-to-excellent short-term outcomes in isolated patellofemoral arthroplasty.

BACKGROUND: In patellofemoral replacement (PFR) coronal alignment is mostly influenced by local condylar anatomy. However, there is still a lack of consensus regarding references to follow intraoperatively for the optimal positioning of the trochlear component. The aim of this study was to assess whether aiming for the anatomical femoral axis on the coronal plane leads to improved clinical outcomes and whether coronal alignment correlates with clinical outcomes. METHODS: Forty-two patients who underwent PFR were retrospectively evaluated at a minimum one-year follow-up using Kujala and Knee Society Score (KSS). Moreover, patients underwent an anteroposterior hip-to-knee X-ray to evaluate the coronal alignment of the trochlear component with respect to the femoral anatomic and mechanical axis. Prosthesis coronal alignment, Kujala, and KSS were assessed for possible correlation. RESULTS: Mean follow-up time: 29.1 months. Mean KSS for pain: 90 (±8.9), for function: 93.7 (±15.9); mean Kujala: 89.2 (±13.6). Mean prosthesis coronal alignment was 3.3 ± 2.3° in valgus with respect to the femoral anatomic axis and 7.4 ± 2.6° in valgus with respect to the femoral mechanical axis. No correlations were found between coronal alignment and KSS or Kujala scores. CONCLUSIONS: Results from the current study showed that PF replacement with a third-generation implant led to good-to-excellent outcomes. In addition, the surgical technique used for aligning femoral component in this study resulted in reduced coronal alignment variability and achieved good short-term clinical outcomes.

Peri-Prosthetic Knee Infection Management: Spacers Loaded with Two or Three Antibiotic Agents.

BACKGROUND: The purpose of this work was to compare pre-made antibiotic-loaded spacers with two commercially available antibiotic agents and custom-made cements with three antibiotic agents added. We evaluated: (a) the validity of our procedures, (b) the control of the rate of infection in the long term, (c) complications, and (d) quality of life and patient satisfaction. METHODS: A retrospective cohort study was performed on 112 consecutively treated patients between January 2010 and December 2013; 56 patients were treated with a pre-formed cement spacer (clindamycin + gentamicin), and 56 patients were treated with a spacer loaded with three antibiotic agents (clindamycin + gentamicin + vancomycin). Demographic data were collected: Classification of infection according to criteria of Cierny-Mader; microbiologic results; number of previous operations; and years of disease. Infection control or relapse after at least 18 months of follow-up was evaluated. Complications were recorded. Every patient completed the SF-36 test and Oxford Knee Score. RESULTS: With a follow-up of 32.87 months (standard deviation 12.04), at the end of treatment, amputation occurred in three of 112 patients because of recurrence of infection, and one patient died from other causes not related to the infection. The study population presented a rate of recurrence of infection of 2.70%. CONCLUSIONS: Our results suggest that a two stage re-implant with three antibiotic agents added to the spacer should be considered to avoid rescue procedures, especially in patients with multi-resistant micro-organism infections.