Prone and direct posterior approach for management of posterior column tibial plateau fractures.

INTRODUCTION: The three-column fixation concept is becoming popular in orthopedic practice. Posterior column fracture is an uncommon type of tibial plateau fracture. The supine position for the surgical approach is familiar to most surgeons; however, it is difficult to achieve good reduction and fixation in posterior column fracture. HYPOTHESES: The prone position and direct posterior approach can achieve proper reduction and fixation for posterior column tibial plateau fracture, yielding good functional outcome. MATERIALS AND METHODS: Between January 2010 and January 2012, 184 tibial plateau fractures were diagnosed and operated on in our institution. Sixteen posterior column tibial plateau fractures (10 male and 6 female patients, with a mean age of 41.5 ± 14.3 years) were diagnosed by preoperative plain films and CT scans. Ten patients presented with fracture-dislocation of the knee joint. A direct posterior approach in prone position was used to reduce the tibial condyle and fix it with an anti-glide buttress plate. Radiographic evaluation included reduction quality and bone union. Functional evaluation included Lysholm score and Tegner activity score. RESULTS: All fractures healed within 6 months, without secondary displacement. Ten knees had postoperative anatomic reduction (0mm step-off) and 6 had acceptable reduction (< 2mm step-off). At 34.4 ± 9.6 months, median extension was 3 (5-10) and flexion 135 (100-145). The mean Lysholm score was 95 (75-100) and the mean Tegner activity score was 6 (5-8). All patients were satisfied with the operation. No cases of post-traumatic osteoarthritis of the knee occurred during follow-up. CONCLUSIONS: The prone position and direct posterior approach has great advantages in terms of reduction and stable fixation, yielding good results.

Transmission and strain variation of Shigella flexneri 4a after mass prophylaxis in a long-stay psychiatric centre.

Shigella flexneri 4a caused sustained outbreaks in a large long-stay psychiatric centre, Taiwan, 2001-2006. Trimethoprim-sulphamethoxazole (SXT) prophylaxis was administered in 2004. We recovered 108 S. flexneri 4a isolates from 83 symptomatic (including one caregiver) and 12 asymptomatic subjects (11 contacts, one caregiver). The isolates were classified into eight antibiogram types and 15 genotypes (six clusters) by using antimicrobial susceptibility testing and pulsed-field gel electrophoresis of NotI-digested DNA, respectively. These characteristics altered significantly after SXT prophylaxis (P < 0·05), with concomitant emergence of SXT-resistant isolates in two antibiogram types. P01 (n = 71), the predominant epidemic genotype, caused infection in two caregivers and five patients under their care; two P01 isolates were recovered from the same patient 6 months apart. These results indicate the importance of sustained person-to-person transmission of S. flexneri 4a by long-term convalescent, asymptomatic or caregiver carriers, and support the emergence of SXT-resistant strains following selective pressure by SXT prophylaxis.