Does lumbar arthrodesis compromise outcome of total hip arthroplasty?

INTRODUCTION: This matched cohort study aims to determine whether the presence of a spinal arthrodesis (SA) compromises outcome of total hip arthroplasty (THA) and whether the outcome is better if THA is performed before- (THA-1st) or after- SA (THA-2nd). METHODS: This is a single centre, multi-surgeon, review of prospective data. Thirty-seven patients (47 hips) that had SA and 1° THA(s), formed the cases (26 THA-1st; 21 THA-2nd). Most cases had 1-level SA (n = 24). Controls were patients without SA that had THA, over the same period matched for age, gender and prosthesis type. Outcome measures included complication-, revision- rates, Oxford-Hip- and Harris-Hip-Scores (OHS/HHS) (Δ: difference between pre- and post-operative scores). This is a single-centre, multi-surgeon, review of prospective data. RESULTS: At a mean follow-up of 6 years, more complications were seen in cases of THA and SA compared with controls without SA (7 vs. 2) (p = 0.03). Consequently, more cases were revised (n = 4) compared with controls (n = 0) (p = 0.02). There were no differences in functional outcome between cases and controls (p = 0.1-0.6). No differences in complications- (4/26 vs. 3/21; p = 1.00) or revision- rates (2/26 vs. 2/21; p = 1.00) were seen between THA-1st and THA-2nd Groups. The THA-1st Group had higher pre- and post-operative OHS/HHS, compared to the THA-2nd Group. However, no significant difference in ΔOHS (24 vs. 17) and ΔHHS (39 vs. 26) were seen between the THA-1st and THA-2nd Groups (p = 0.1). CONCLUSIONS: Patients with THA and SA, had increased rates of revision; but no differences in patient-reported outcome measures (PROMs) were detected. Addressing the hip pathology first may be associated with improved functional outcome.

Role of trehalose biosynthesis in environmental survival and virulence of Salmonella enterica serovar typhimurium.

The otsA and otsB genes, encoding trehalose-6-phosphate synthase and trehalose-6-phosphate phosphatase respectively, have been isolated from Salmonella enterica serovar typhimurium and nucleotide-sequenced. Induction of trehalose biosynthesis by exposure of bacteria to high osmotic strength resulted in the intracellular accumulation of trehalose. An otsA mutant of S. enterica serovar typhimurium was more susceptible to killing by heat, and grew poorly under conditions of high osmolarity. The wild-type and otsA mutant strains showed similar abilities to colonise spleen tissues after oral dosing of mice. These findings suggest that the otsBA gene products play a role in environmental survival, but not in virulence, of S. enterica serovar typhimurium.