Aims

Nonagenarians (aged 90 to 99 years) have experienced the fastest percent decile population growth in the USA recently, with a consequent increase in the prevalence of nonagenarians living with joint arthroplasties. As such, the number of revision total hip arthroplasties (THAs) and total knee arthroplasties (TKAs) in nonagenarians is expected to increase. We aimed to determine the mortality rate, implant survivorship, and complications of nonagenarians undergoing aseptic revision THAs and revision TKAs.

Aims

This study aimed to investigate the estimated change in primary and revision arthroplasty rate in the Netherlands and Denmark for hips, knees, and shoulders during the COVID-19 pandemic in 2020 (COVID-period). Additional points of focus included the comparison of patient characteristics and hospital type (2019 vs COVID-period), and the estimated loss of quality-adjusted life years (QALYs) and impact on waiting lists.

Aims

The primary aim of this study was to compare the wear properties of vitamin E-diffused, highly crosslinked polyethylene (VEPE) and one formulation of moderately crosslinked and mechanically annealed ultra-high molecular weight polyethylene (ModXLPE) in patients five years after primary total hip arthroplasty (THA). The secondary aim was to assess the clinical results of patients treated with VEPE by evaluating patient-reported outcome measures (PROMs), radiological evidence of fixation, and the incidence of mechanical failure.

Aims

The aim of this study was to assess the effect of multimorbidity on improvements in health-related quality of life (HRQoL) following total hip arthroplasty (THA) and total knee arthroplasty (TKA).

Aims

The interaction between surgical lighting and laminar airflow is poorly understood. We undertook an experiment to identify any effect contemporary surgical lights have on laminar flow and recommend practical strategies to limit any negative effects.

Objectives

Computed tomography (CT) plays an important role in evaluating wear and periacetabular osteolysis (PAO) in total hip replacements. One concern with CT is the high radiation exposure since standard pelvic CT provides approximately 3.5 millisieverts (mSv) of radiation exposure, whereas a planar radiographic examination with three projections totals approximately 0.5 mSv. The objective of this study was to evaluate the lowest acceptable radiation dose for dual-energy CT (DECT) images when measuring wear and periacetabular osteolysis in uncemented metal components.

The aim of our study was to describe the characteristics, treatment, and outcomes of patients with periprosthetic joint infection (PJI) and normal inflammatory markers after total knee arthroplasty (TKA) and total hip arthroplasty (THA).

In total 538 TKAs and 414 THAs underwent surgical treatment for PJI and met the inclusion criteria. Pre-operative erythrocyte sedimentation rate (ESR) and C-reactive protein level (CRP) were reviewed to identify the seronegative cohort. An age- and gender-matched cohort was identified from the remaining patients for comparison. Overall, 4% of confirmed infections were seronegative (21 TKA and 17 THA). Of those who underwent pre-operative aspiration, cultures were positive in 76% of TKAs (n = 13) and 64% of THAs (n = 7). Cell count and differential were suggestive of infection in 85% of TKA (n = 11) and all THA aspirates (n = 5). The most common organism was coagulase-negative Staphylococcus. Seronegative infections were associated with a lower aspirate cell count and a lower incidence of Staphylococcus aureus infection. Two-stage revision was performed in 35 cases (95%). At a mean of five years (14 to 162 months) following revision, re-operation for infection occurred in two TKAs, and one THA. From our study we estimate around 4% of patients with PJI may present with normal ESR and CRP. When performed, pre-operative aspirate is useful in delivering a definitive diagnosis. When treated, similar outcomes can be obtained compared with patients with positive serology.

Cite this article: Bone Joint J 2015;97-B:939–44.

We performed a meta-analysis of modern total joint replacement (TJR) to determine the post-operative mortality and the cause of death using different thromboprophylactic regimens as follows: 1) no routine chemothromboprophylaxis (NRC); 2) Potent anticoagulation (PA) (unfractionated or low-molecular-weight heparin, ximelagatran, fondaparinux or rivaroxaban); 3) Potent anticoagulation combined (PAC) with regional anaesthesia and/or pneumatic compression devices (PCDs); 4) Warfarin (W); 5) Warfarin combined (WAC) with regional anaesthesia and/or PCD; and 6) Multimodal (MM) prophylaxis, including regional anaesthesia, PCDs and aspirin in low-risk patients. Cause of death was classified as autopsy proven, clinically certain or unknown. Deaths were grouped into cardiopulmonary excluding pulmonary embolism (PE), PE, bleeding-related, gastrointestinal, central nervous system, and others (miscellaneous). Meta-analysis based on fixed effects or random effects models was used for pooling incidence data.

In all, 70 studies were included (99 441 patients; 373 deaths). The mortality was lowest in the MM (0.2%) and WC (0.2%) groups. The most frequent cause of death was cardiopulmonary (47.9%), followed by PE (25.4%) and bleeding (8.9%). The proportion of deaths due to PE was not significantly affected by the thromboprophylaxis regimen (PA, 35.5%; PAC, 28%; MM, 23.2%; and NRC, 16.3%). Fatal bleeding was higher in groups relying on the use of anticoagulation (W, 33.8%; PA, 9.4%; PAC, 10.8%) but the differences were not statistically significant.

Our study demonstrated that the routine use of PA does not reduce the overall mortality or the proportion of deaths due to PE.

We have investigated whether the use of laminar-flow theatres and space suits reduced the rate of revision for early deep infection after total hip (THR) and knee (TKR) replacement by reviewing the results of the New Zealand Joint Registry at ten years.

Of the 51 485 primary THRs and 36 826 primary TKRs analysed, laminar-flow theatres were used in 35.5% and space suits in 23.5%. For THR there was a significant increase in early infection in those procedures performed with the use of a space suit compared with those without (p < 0.0001), in those carried out in a laminar-flow theatre compared with a conventional theatre (p < 0.003) and in those undertaken in a laminar-flow theatre with a space suit (p < 0.001) when compared with conventional theatres without such a suit. The results were similar for TKR with the use of a space suit (p < 0.001), in laminar-flow theatres (p < 0.019) and when space suits were used in those theatres (p < 0.001). These findings were independent of age, disease and operating time and were unchanged when the surgeons and hospital were analysed individually.

The rate of revision for early deep infection has not been reduced by using laminar flow and space suits. Our results question the rationale for their increasing use in routine joint replacement, where the added cost to the health system seems to be unjustified.

Between 1988 and 1998 we implanted 318 total hip replacements (THRs) in 287 patients using the Plasmacup (B. Braun Ltd, Sheffield, United Kingdom) and a conventional metal-on-polyethylene articulation. The main indications for THR were primary or secondary osteoarthritis.

At follow-up after a mean 11.6 years (7.6 to 18.4) 17 patients had died and 20 could not be traced leaving a final series of 280 THRs in 250 patients. There were 62 revisions (22.1%) in 59 patients. A total of 43 acetabular shells (15.4%) had been revised and 13 (4.6%) had undergone exchange of the liner. The most frequent indications for revision were osteolysis and aseptic loosening, followed by polyethylene wear. The mean Kaplan-Meier survival of the Plasmacup was 91% at ten years and 58% at 14 years. Osteolysis was found around 36 (17.1%) of the 211 surviving shells. The median annual rate of linear wear in the surviving shells was 0.12 mm/year and 0.25 mm/year in those which had been revised (p < 0.001). Polyethylene wear was a strong independent risk factor for osteolysis and aseptic loosening. The percentage of patients with osteolysis increased proportionately with each quintile of wear-rate.

There is a high late rate of failure of the Plasmacup. Patients with the combination of this prosthesis and bearing should be closely monitored after ten years.

Balancing service provision and surgical training is a challenging issue that affects all healthcare systems. A multicentre prospective study of 1501 total hip replacements was undertaken to investigate whether there is an association between surgical outcome and the grade of the operating surgeon, and whether there is any difference in outcome if surgeons’ assistants assist with the operation, rather than orthopaedic trainees. The primary outcome measure was the change in the Oxford hip score (OHS) at five years. Secondary outcomes included the rate of revision and dislocation, operating time, and length of hospital stay.

There was no significant difference in ΔOHS or complication rates between operations undertaken by trainers and trainees, or those at which surgeons’ assistants and trainees were the assistant. However, there was a significant difference in the duration of surgery, with a mean reduction of 28 minutes in those in which a surgeons’ assistant was the assistant.

This study provides evidence that total hip replacements can be performed safely and effectively by appropriately trained surgeons in training, and that there are potential benefits of using surgeons’ assistants in orthopaedic surgery.

The routine use of surgical drains in total hip arthroplasty remains controversial. They have not been shown to decrease the rate of wound infection significantly and can provide a retrograde route for it. Their use does not reduce the size or incidence of post-operative wound haematomas. This prospective, randomised study was designed to evaluate the role of drains in routine total hip arthroplasty.

We investigated 552 patients (577 hips) undergoing unilateral or bilateral total hip arthroplasty who had been randomised to either having a drain for 24 hours or not having a drain. All patients followed standardised pre-, intra-, and post-operative regimes and were independently assessed using the Harris hip score before operation and at six, 18 and 36 months follow-up.

The rate of superficial and deep infection was 2.9% and 0.4%, respectively, in the drained group and 4.8% and 0.7%, respectively in the undrained group. One patient in the undrained group had a haematoma which did not require drainage or transfusion. The rate of transfusion after operation in the drained group was significantly higher than for undrained procedures (p < 0.042). The use of a drain did not influence the post-operative levels of haemoglobin, the revision rates, Harris hip scores, the length of hospital stay or the incidence of thromboembolism. We conclude that drains provide no clear advantage at total hip arthroplasty, represent an additional cost, and expose patients to a higher risk of transfusion.

We have investigated the contaminating bacteria in primary hip arthroplasty and their sensitivity to the prophylactic antibiotics currently in use. Impressions (627) of the gloved hands of the surgical team in 50 total hip arthroplasties were obtained on blood agar. The gloves were changed after draping, at intervals of 20 minutes thereafter, and before using cement. Changes were also undertaken whenever a visible puncture was detected. The culture plates were incubated at 37°C for 48 hours. Isolates were identified and tested for sensitivity to flucloxacillin, which is a recognised indicator of sensitivity to cefuroxime. They were also tested against other agents depending upon their appearance on Gram staining.

We found contamination in 57 (9%) impressions and 106 bacterial isolates. Coagulase-negative staphylococci were seen most frequently (68.9%), but we also isolated Micrococcus (12.3%), diphtheroids (9.4%), Staphylococcus aureus (6.6%) and Escherichia coli (0.9%). Of the coagulase-negative staphylococci, only 52.1% were sensitive to flucloxacillin and therefore to cefuroxime. We believe that it is now appropriate to review the relevance of prophylaxis with cefuroxime and to consider the use of other agents.

Between 1971 and 1991 we performed Charnley low-friction arthroplasty (LFA) on 116 patients (186 hips) with juvenile chronic arthritis (JCA). We have now carried out a survival study, taking endpoints as revision, death or the end of the year 1993. Overall survival was 91.9% at ten years and 83.0% at 15 years. That of the femoral component was 95.6% at ten years and 91.9% at 15 years and of the acetabulum 95.0% and 87.8%, respectively. Only the use of steroids significantly impaired the survival. We therefore recommend the use of Charnley LFA for young patients with JCA requiring total hip replacement

We studied the risk of recurrent dislocation in 121 primary and 39 revision Charnley or Charnley hybrid total hip arthroplasties which had been treated for a primary dislocation between 1979 and 1995. Only 35% of these hips had no further dislocation or a revision for instability within one year. The rates of survival gradually declined with time or if a second, third or fourth dislocation occurred. The risk of recurrence was greater in men, but was not related to age, diagnosis, time of the first dislocation or whether the index operation had been a primary or a revision procedure. Operative treatment included 15 reoperations leaving intact components, 50 revisions, and permanent removal of the femoral stem in seven patients. The operation was successful in four patients with reoperations and in 36 who had an exchange procedure within two years. Treatment was successful in 35 of 49 hips in which it was possible to correct a technical error compared with 5 out of 16 hips in which malposition of the components was not seen (p = 0.007)

A consecutive series of 30 total hip replacements using a hydroxyapatite (HA)-coated, modular implant (Omnifit) was followed clinically and by roentgen stereophotogrammetric analysis for two years and compared with two control groups, one of 27 cemented Charnley sockets and one of 40 cemented Charnley stems. Omnifit sockets with a central gap between the dome of the socket and the acetabular bone in the postoperative radiographs, migrated less than sockets without such gaps (p = 0.01). After adjustment for patient-related factors (age, gender and weight), no significant difference was found between the two prostheses with respect to micromotion and wear. We conclude that the early fixation of the HA-coated Omnifit prosthesis compares with that of the cemented Charnley prosthesis

We studied wear in the ultra-high-molecular-weight polyethylene offset bore socket in 54 hips which had had Charnley low-friction arthroplasty. At an average follow-up of 8.1 years, the mean penetration rate was 0.04 mm per year. Correlation between the depth of socket penetration and the incidence of socket migration was confirmed, but socket migration occurred with lower penetration than had been previously reported