Aim. Previous publications have suggested that the incidence of revisions due to infection after THA is increasing. We performed updated time-trend analyses of risk and timing of revision due to infection after primary THAs in the Nordic countries during the period 2004–2018. Methods. 569,463 primary THAs reported to the Nordic Arthroplasty Register Association from 2004 through 2018 were studied. We estimated adjusted hazard ratios (aHR) with 95% confidence interval by Cox regression with the first revision due to infection after primary THA as endpoint. The risk of revision was investigated. In addition, we explored changes in the time span from primary THA to revision due to infection. Results. 5,653 (1.0%) were revised due to infection. The risk of revision due to infection increased through the study period. Compared to the period 2004–2008, the aHRs were 1.4 (95%CI 1.3–1.5) for 2009–2013, and 1.9 (1.7–2.0) for 2014–2018. We found an increased risk in all four Nordic countries. Compared to 2004–2008, the aHR due to infection 0–30 days after THA was 2.5 (2.1–2.9) for 2009–2013 and 3.4 (3.0–3.9) for 2013–2018. The aHR of revision due to infection 31–90 days after THA was 1.5 (1.3–1.9) for 2009–2013 and 2.5 (2.1–3.0) for 2013–2018, compared to 2004–2008. Beyond 91 days after THA, the risk of revision due to infection was stable over the whole study period. Interpretation. The risk of revision due to deep infection after THA nearly doubled throughout the period 2004–2018. This increase was mainly due to an increased risk of early revisions. The cause for these changes may be multifactorial (patient selection, diagnostics, revision strategy, completeness of reporting, etc.), are not possible to disclose in the present study, and warrants further research

Background. Substance abuse and dependence is thought to have a strongly negative impact on surgical outcomes. The purpose of this study was to determine the effects of drug misuse on total knee arthroplasty (TKA) revision incidence, revision causes, and time to revision by analyzing the Medicare database between 2005–2012. Methods. A retrospective review of the Medicare database within the PearlDiver Supercomputer (Warsaw, IN) for TKA and revisions was performed utilizing Current Procedural Terminology (CPT) and International Classification of Disease (ICD) ninth revision codes. Drug misuse was subdivided into cocaine, cannabis, opioids, sedative/hypnotic/anxiolytic, amphetamines, and alcohol. Time to revision, age, and gender were also investigated. Results. Our query returned 2159221 TKAs and 193024 (8.9%) revisions between 2005–2012. Drug misuse was prevalent in 173513 (8%). Cocaine had the highest revision incidence (13.9%). Cannabis had the fastest average (636.1 days) and median (457 days) time to revision. At 30 and 90 days, cannabis had the greatest rate of revision at 6% and 12% respectively. At 6 months and 1 year, amphetamine had the greatest revision risk at 25% and 40.5% respectively. Infection was the most common cause of revision among all substances. Conclusion. Cocaine misuse holds the highest risk for revision. However cannabis misuse is more likely to require revision sooner, particularly at the 30 and 90 day intervals. Infection was the most common cause of revision regardless of substance misused. Thus it is important to obtain a detailed social history on drug misuse and to be vigilant for postoperative infections in these patients

Ceramic-on-polyethylene (COP) bearings have traditionally been reserved for younger patients that were at high risk of polyethylene wear requiring revision. With the 1999 advent of highly crosslinked polyethylene (XLP), wear with XLP has not been a cause for revision. Simulator studies have not shown a difference in wear comparing COP to metal-on-polyethylene (MOP). Therefore, and considering the additional cost of COP, we have until recently not needed COP. However, a 2012 report of 10 cases that developed an adverse reaction to metal debris generated by head neck corrosion has resulted in COP becoming the most common bearing surface as reported by the American Joint Replacement Registry. This reactionary change has occurred despite the fact that we do not understand the cause, do not know the frequency, if it is more common in some implants than others, and we do not know the additional cost or markup of ceramic heads. One study reported a 3.2% revision prevalence caused by mechanically assisted crevice corrosion (MACC) at the head neck junction of a single manufacturer's implant. Other studies have estimated the frequency to be less than 5%. COST IS THE CONCERN in a value based healthcare environment. Models for and against the wholesale use of COP have been proposed and are based on variables that are unknown, including estimated frequency of the problem and the incrementally higher cost of a ceramic head. I use COP in younger patients that I believe will use their hip for more than 15 years. This is based on my personal experience. I have prospectively followed a series of MOP patients for 5 years and not seen cobalt elevations. I have placed new metal femoral heads on corroded femoral tapers without subsequent failure. I have evaluated the taper junctions of postmortem retrievals and found them virtually free of corrosion. A query of our institutional database for MOP primary hips identified 3012 cases between 2006–2017. Eighty revisions (2.7%) were identified. 2 of the 80 were for MACC representing 2.5% of revisions done on our own patients and 0.07% of our MOP cases. Further, evaluating our most recent all cause 350 revisions (7/2015–10/2017) there were 3 revisions for MACC (0.9%). Each one of us needs to EVALUATE OUR OWN PRACTICE AND MAKE AN EDUCATED, VALUE BASED DECISION whether or not to use COP in all patients

Ceramic-on-polyethylene (COP) bearings have traditionally been reserved for younger patients that were at high risk of polyethylene wear requiring revision. With the 1999 advent of highly crosslinked polyethylene (XLP), wear with XLP has not been a cause for revision. Simulator studies have not shown a difference in wear comparing COP to metal-on-polyethylene (MOP). Therefore, and considering the additional cost of COP, we have until recently not needed COP. However, a 2012 report of 10 cases that developed an adverse reaction to metal debris generated by head neck corrosion has resulted in COP becoming the most common bearing surface as reported by the American Joint Replacement Registry. This reactionary change has occurred despite the fact that we do not understand the cause, do not know the frequency, if it is more common in some implants than others, and we do not know the additional cost or markup of ceramic heads. One study reported a 3.2% revision prevalence caused by mechanically assisted crevice corrosion (MACC) at the head neck junction of a single manufacturer's implant. Other studies have estimated the frequency to be less than 5%. COST IS THE CONCERN in a value based health care environment. Models for and against the wholesale use of COP have been proposed and are based on variables that are unknown, including estimated frequency of the problem and the incremental cost of a ceramic head. I use COP in younger patients that I believe will use their hip for more than 15 years. This is based on my personal experience. I have prospectively followed a series of MOP patients for 5 years and not seen cobalt elevations. I have placed new metal femoral heads on corroded femoral tapers without subsequent failure. I have evaluated the taper junctions of postmortem retrievals and found them virtually free of corrosion. A query of our institutional database for MOP primary hips identified 3012 cases between 2006–2017. Eighty revisions (2.7%) were identified. Two of the 80 were for MACC representing 2.5% of revisions done on our own patients and 0.07% of our MOP cases. Further, evaluating our most recent all cause 350 revisions (7/2015-10/2017) there were 3 revisions for MACC (0.9%). Each one of us needs to EVALUATE OUR OWN PRACTICE AND MAKE AN EDUCATED, VALUE BASED DECISION whether or not to use COP in all patients

Total hip arthroplasty (THA) is a common and extremely beneficial procedure that is being performed more often as the population ages. Current THA follow-up guidelines require large amounts of resources and may not justify their cost with increased patient outcomes. Most problems that would require THA revision will cause symptoms. Late-presenting asymptomatic THAs that are found to require revision are complicated and expensive to address and often lead to poor patient outcomes. Follow-up visits for THA patients are essentially a screening tool to identify asymptomatic THAs that require revision. The rate of asymptomatic THA revision and the subsequent cost of screening for them is not well reported in the literature. Given the relative shortage of orthopaedic resources, efficient use of clinic time should be a priority and inefficient practices should be identified and changed. We calculated the rate of asymptomatic hip revisions over the first twenty years of THA ownership. We further calculated the cost of a single visit to the orthopaedic clinic for follow up of a THA. Finally, we calculated the cost savings of decreasing the follow-up schedule to a total of three visits. The cost savings of foregoing the screening to identify one asymptomatic THA requiring revision is CAD $1.2 million. Asymptomatic THAs requiring revision are rare and, as such, require a large amount of follow up to diagnose. As a screening tool, regular orthopaedic follow up of THA is an inefficient use of resources. Current follow-up guidelines are cost-prohibitive and should be made much less frequent in order to save resources

The aim was to identify the acetabular center, fix the acetabular implant, and reconstruct the hip rotation center using the residual Harris fossa and acetabular notch as anatomical markers during revision hip arthroplasty. Osteolysis is commonly found in the acetabulum during hip arthroplasty revision. It causes extensive defects and malformation of the anatomical structure, making correct fixation of a hip prosthesis difficult. We studied the relations of the anatomical positions between the Harris fossa and acetabular notch and the acetabular center (Fig. 1). Vertical distance from the hip rotation center to the teardrop connection and horizontal distance from the hip rotation center to the teardrop were measured on preoperative and postoperative radiographs. Vertical distance increased from 14.22±3.39 mm preoperatively to 32.64±4.51 mm postoperatively (t=3.65, P<0.05) and the horizontal distance from 25.13±3.46 mm to 32.87±4.73 mm (t=2.72, P<0.05). Altogether, 28 patients underwent revision hip arthroplasty based on the Paprosky classification for bone loss. The anatomical hip center was identified using the residual Harris fossa and acetabular notch as anatomical markers during revision hip arthroplasty. Based on these relations, we were able to place the hip prosthesis correctly. After surgery, restoration of the anatomical hip center was accomplished based on data obtained from radiographs(Fig.2 and Fig.3)

EPRs are the treatment of choice following resection of tumours. These have been used for 39 years in our institution. There has been concern regarding the long term survival of endoprosthesis; this study investigates the fate of the reconstruction. Methods. Between 1966 and 1995, 3716 patients were seen with a suspected neoplasm and 776 patients underwent EPRs. Patients receiving growing endoprostheses were excluded from the study as they invariably require revision, leaving 667 replacements. Insufficient data was available in 6 cases, leaving 661 patients in the study group. Information was reviewed concerning the diagnosis, survival of implant and patient, subsequent surgery, complications and functional outcome. Kaplan-Meier survival analysis was used for implant survival with end points defined as revision for mechanical failure (aseptic loosening, implant fracture, instability, avascular necrosis, periprosthetic fracture, pain and stiffness) and revision for any cause (infection, local recurrence and mechanical failure). Results. Mean age at diagnosis was 34 years. Overall patient survival was 52.7% at 10 years and 45.7% at 20 years. The mean follow-up for all patients was 9 years, and for those patients who survived their original disease, the mean follow-up was 15 years. 227 (34%) patients underwent revision surgery, 75 patients for infection (33%), 36 patients for locally recurrent disease (16%) and mechanical failure in 116 patients (51%). With revision for mechanical failure as the end-point, implant survival was 75% at 10 years and 52% at 20 years. With revision any cause as an end-point implant survival was 58% at 10 years and 38% at 20 years. Overall limb salvage was maintained in 91% of patients at 10 years from reconstruction and 79% at 20 years. There was a significant difference between survival of implant between implantation sites, with the proximal humeral implant survival being the best and tibial reconstructions being the worst. The MTSS functional score was available on 151 patients, with a mean score of 25/30 (83%) at last follow-up visit. Discussion. Our results are comparable with other series of long term follow-up and justifies their continued use