Comparison of clinical outcomes between posterolateral approach and modified Hardinge approach in salvage total hip arthroplasty after medial buttress plate failure for femoral neck fractures

OBJECTIVE

The purpose of this study was to investigate the clinical outcomes of salvage total hip arthroplasty (THA) after medial buttress plate surgery for femoral neck fractures via the modified Hardinge approach (MHA) and posterolateral approach (PLA) through a retrospective analysis.

PATIENTS AND METHODS

From October 2016 to October 2020, a total of 41 patients with failed femoral neck fractures treated with cannulated screws and medial buttress plates underwent unilateral salvage THA, and a retrospective study was conducted. According to the surgical approach, patients were divided into PLA group and MHA group. Clinical and radiological data were evaluated. The primary outcome indicators were the Pain Visual Analog Scale (VAS) and Hip Harris Score (HHS). Secondary outcome indicators include hemoglobin (HGB), hematocrit (HCT), creatine kinase (CK), creatine kinase-MB (CK-MB), etc. The occurrence of postoperative complications was also recorded.

RESULTS

There were no differences in demographic or clinical characteristics before surgery. There were no differences in postoperative HGB, HCT, CK-MB and radiological parameters. The surgical approach had no effect on the hospitalization period. The PLA group had earlier ambulation time, and the serum level of CK was also low. Analysis of the HHS and VAS showed that on postoperative day 3, the PLA group had superior scores. The incidence of complications did not significantly differ between groups.

CONCLUSIONS

The posterolateral approach for salvage THA provides better functional recovery with less muscle damage in the early postoperative period.

Real-time quantifications of dominant anaerobes in an upflow reactor by polymerase chain reaction using a TaqMan probe

This study was conducted to demonstrate the application of quantitative real-time polymerase chain reaction (qRT-PCR) for the quantification of dominant bacteria in an anaerobic reactor using a designed TaqMan probe. A novel group of uncultured thermophilic bacteria affiliated with Thermotogales was first found in a phenol-degrading sludge from a 55 degrees C upflow anaerobic sludge blanket (UASB) reactor, which effectively removed 99% of phenol at loading of 0.51 g-phenol l(-1) d(-1) h of hydraulic retention. A TaqMan probe was then designed targeting this group of Thermotogales affiliated bacteria (TAB), and used to monitor its concentration in the reactors. Results showed that the TAB population in the 55 degrees C reactor increased proportional to the phenol degrading rate. Results also showed that the TAB population ranged 3.5-9.9% in the 55 degrees C phenol-degrading sludge, but only 0.0044% in the 37 degrees C sludge and 0.000086% in the 26 degrees C sludge.

Anaerobic treatment of phenol in wastewater under thermophilic condition

Over 99% of phenol was effectively degraded in an upflow anaerobic sludge blanket (UASB) reactor at 55 degrees C with 40 h of hydraulic retention time (HRT) for a wastewater containing 630 mg/L of phenol, corresponding to 1500 mg/L of chemical oxygen demand (COD) and a loading rate of 0.9 g-COD/L/d. The maximum specific methanogenic activity (SMA) of the phenol-degrading sludge was 0.09 g-CH4-COD/g-volatile suspended solids (VSS)/d. Based on 16S rDNA analysis, a total of 21 operational taxonomy units (OTUs) were found in the sludge, of which eight (42.6% of the total population) were related to the sequences in the GenBank with similarity of over 97%, and 13 (79.6%) were affiliated with the known thermophilic species. Additional SMA data and phylogenetic analysis suggest that the degradation pathway of phenol for thermophilic sludge was likely via caproate, instead of benzoate as for the mesophilic sludge.