Introduction

Embolism in total arthroplasty or hip fractures, coagulation disorders, such as a variety of ways for the prevention of complications of anticoagulation therapy with medication is being done well. The purpose of this study, a representative of the anticoagulation therapy with enoxaparin and drug rivaroxaban of coagulation tests performed in patients between the two groups was to determine whether statistically significant differences.

National guidelines suggest which investigations should be performed for patients admitted with an acute hip fracture. We have observed practice often deviates from these guidelines. Our study aims to identify the incidence of deviation with regards to blood investigations and review the effect of deviation on management, and the financial burden on the healthcare system. A total of 250 acute hip fracture admissions over 12-months period reviewed retrospectively. Admission blood tests, time of presentation, and time of operation were recorded. The cost of admission blood investigations was calculated. Seventy-nine percent of admissions had one or more non-routine blood investigation tested. Twenty-Nine percent of these tests had abnormal results and these were found to be clinically relevant in 6% of patients. The most commonly requested non-routine investigations were: LFT in 79%, Coagulation screen in 56%, and CRP in 48%. Fifteen percent of patients did not have surgery within the time frame of 36 hours. The total cost of non-routine investigations was £1995.04. Deviation from admission investigations guidelines for hip fractures without clinical indication adds little clinical value, has no effect on management, and can be a potential cause of unnecessary investigations. This in turn leads to further delays and extra costs

Recently, a special type of surface pitting found on metal implants was proposed to arise from “inflammatory cell-induced” corrosion (ICI, Figure 1) (1, 2). The actual mechanism of this was unknown, but similar features were suggested to be artefacts of electrocautery damage from revision surgery (3). Under lab conditions and without the influence of any cells, we aimed to reproduce the same surface pits and structures with electrocautery. Methods. A polished cobalt-chromium disk (40 mm diameter, 8 mm thick) was marked into 8 sections for various testing conditions (Figure 2a). A stainless steel Bovie tip with a unipolar electrocautery machine (SYSTEM 5000, ConMed, USA) was used at typical surgical coagulation conditions: (70 volt, 120 watts, 562 KHz frequency). We mimicked three types of surgical techniques with the electrocautery: “Dotting” was repeated, on and off, direct surface contact; “Dragging” was constant, direct surface contact; “Hovering” was pausing several millimeters above the surface. We also examined the interplay of these practices on diamond-tip-induced scratches and either dry or wet (normal saline) conditions. High magnification images (Keyence VHX-2000E) were taken after the disk was cleaned with laboratory soap, light mechanical scrubbing, and formalin soak. Results. Coagulation mode generated electrical sparks when dotting/dragging and electrical arcs when hovering. These left seared marks that persisted even after cleaning (Figure 2b). At higher magnification, the surface features were comparable in size and shape to those attributed to ICI (1, 2). Areas wet with saline (Figure 3a) showed an abundance of ringed pits with raised edges that closely resembled those observed in Figure 1. Furthermore we obtained images similar to the phenomenon of “cellular tracks” (Figure 3b) (1). Premade scratches did not influence the pit arrangement but scratches made by the Bovie tip produced the characteristic scratch-associated ICI features as observed on implant retrievals in the past (Figure 3c) (4). Discussion. In the absence of cells, pitting equivalent to proposed ICI features was successfully replicated using an electrocautery in coagulation mode. Previously (4), we found a high incidence but small surface area of these features on the majority of retrievals, predominantly located in a focal area of the superior aspect of the femoral ball next to the junction of the stem. There were fewer on the inferior aspect which is consistent with electocautery damage when dissecting the hip capsule. The effect of this damage on retained parts is unknown, but electrocautery damage around areas of implant fractures has been reported (3). Conclusion. The striking similarities of the recreated pit structures imaged here suggest that the noted features of “inflammatory cell induced corrosion” were artefacts of the electrocautery during revision surgery. Future implant retrieval analysis should acknowledge these structures are not related to any particular mode of failure but should check for them around implant fracture sites