Financial analysis of revision knee surgery at a tertiary referral centre as classified according to the Revision Knee Complexity Classification (RKCC).

BACKGROUND: Revision total knee arthroplasty (rTKA) can be complex, with greater costs to the treating hospital than primary TKA. A rTKA regional network has been proposed in England. The aim of this work was to accurately quantify current costs and reimbursement for the rTKA service and to assess whether costs are proportional to case complexity at a tertiary referral centre within the National Health Service (NHS). METHODS: A review of all rTKA performed at our institution over two consecutive financial years (2017-2019) was performed. Cases were classified according to the Revision Knee Complexity Classification (RKCC) and by mode of failure; "infected" and "non-infected". Financial data was acquired through Patient-Level Information and Costing System (PLICS). The primary outcome was the financial difference between tariff and cost per episode. Comparisons between groups were analysed using analysis of variance and two-tailed unpaired t-test as appropriate. RESULTS: 159 patients underwent 188 rTKA procedures. Length of stay and cost significantly increased between complexity groups (p < 0.0001) and for infected revisions (p < 0.0001). All groups sustained a mean deficit but this significantly increased with revision complexity (from £1,903 to £5,269 per case) and for infected revisions. The total deficit to the Trust for the two-year rTKA service was £667,091. CONCLUSIONS: The current level of NHS reimbursement are inadequate for centres that offer rTKA and should be more closely aligned to case complexity. An increase in the most complex rTKA at major revision centres will undoubtedly place an even greater strain on the finances of these units.

Long-term results of acetabular reconstruction using irradiated allograft bone.

AIMS: The management of acetabular defects at the time of revision hip arthroplasty surgery is a challenge. This study presents the results of a long-term follow-up study of the use of irradiated allograft bone in acetabular reconstruction. PATIENTS AND METHODS: Between 1990 and 2000, 123 hips in 110 patients underwent acetabular reconstruction for aseptic loosening, using impaction bone grafting with frozen, irradiated, and morsellized femoral heads and a cemented acetabular component. A total of 55 men and 55 women with a mean age of 64.3 years (26 to 97) at the time of revision surgery are included in this study. RESULTS: At a mean follow-up of 16.9 years, there had been 23 revisions (18.7%), including ten for infection, eight for aseptic loosening, and three for dislocation. Of the 66 surviving hips (58 patients) that could be reassessed, 50 hips (42 patients; 75.6%) were still functioning satisfactorily. Union of the graft had occurred in all hips with a surviving implant. Survival analysis for all indications was 80.6% at 15 years (55 patients at risk, 95% confidence interval (CI) 71.1 to 87.2) and 73.7% at 20 years (eight patients at risk, 95% CI 61.6 to 82.5). CONCLUSION: Acetabular reconstruction using frozen, irradiated, and morsellized allograft bone and a cemented acetabular component is an effective method of treatment. It gives satisfactory long-term results and is comparable to other types of reconstruction. Cite this article: Bone Joint J 2018;100-B:1449-54.

Hemoglobin damages the cultured endothelial cell monolayer from bovine cerebral arteries.

We demonstrated that hemoglobin reaches the endothelial layers by an immunoelectron microscopic analysis in a rabbit subarachnoid hemorrhage model. Next, the effects of hemoglobin on cerebral artery endothelial cells were investigated both morphologically and histochemically using a cultured monolayer from a bovine endothelial cell system. The cultured monolayer was incubated with six different concentrations of hemoglobin ranging from 0 to 10(-5) M for 24 hrs on two-chambered glass slides. The denuded area of the glass slide increased dose dependently while the intensity of the actin fiber decreased. Superoxide dismutase did not modify this change. In a preliminary study, the endothelial cell membrane showed a hemoglobin binding molecule (94.5k dalton). This study thus suggests that the effects of hemoglobin on the endothelial monolayer were partly caused by the direct binding of hemoglobin to the membrane.