There is a large amount of evidence available
about the relative merits of unicompartmental and total knee arthroplasty
(UKA and TKA). Based on the same evidence, different people draw
different conclusions and as a result, there is great variability
in the usage of UKA. The revision rate of UKA is much higher than
Rates of readmission and reoperation following primary total knee arthroplasty (TKA) are under scrutiny due to new payment models, which penalize these negative outcomes. Some risk factors are more modifiable than others, and some conditions considered modifiable such as obesity may not be as modifiable in the setting of advanced arthritis as many propose. We sought to determine whether controlling for hypoalbuminaemia would mitigate the effect that prior authors had identified in patients with obesity. We reviewed the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database for the period of January 2008 to December 2016 to evaluate the rates of reoperation and readmission within 30 days following primary TKA. Multivariate logistic regression modelling controlled for preoperative albumin, age, sex, and comorbidity status.Aims
Methods
Periprosthetic joint infection (PJI) is one of
the most feared and challenging complications following
Objectives. Initial stability of tibial trays is crucial for long-term success of
The complex relationship between acetabular component position and spinopelvic mobility in patients following total hip arthroplasty (THA) renders it difficult to optimize acetabular component positioning. Mobility of the normal lumbar spine during postural changes results in alterations in pelvic tilt (PT) to maintain the sagittal balance in each posture and, as a consequence, markedly changes the functional component anteversion (FCA). This study aimed to investigate the in vivo association of lumbar degenerative disc disease (DDD) with the PT angle and with FCA during postural changes in THA patients. A total of 50 patients with unilateral THA underwent CT imaging for radiological evaluation of presence and severity of lumbar DDD. In all, 18 patients with lumbar DDD were compared to 32 patients without lumbar DDD. In vivo PT and FCA, and the magnitudes of changes (ΔPT; ΔFCA) during supine, standing, swing-phase, and stance-phase positions were measured using a validated dual fluoroscopic imaging system.Aims
Methods
Aims. This prospective randomised controlled trial was designed to
evaluate the outcome of both the MRI- and CT-based patient-specific
matched guides (PSG) from the same manufacturer. Patients and Methods. A total of 137 knees in 137 patients (50 men, 87 women) were
included, 67 in the MRI- and 70 in the CT-based PSG group. Their
mean age was 68.4 years (47.0 to 88.9). Outcome was expressed as
the biomechanical limb alignment (centre hip-knee-ankle: HKA-axis)
achieved post-operatively, the position of the individual components
within 3° of the pre-operatively planned alignment, correct planned
implant size and operative data (e.g. operating time and blood loss). Results. The patient demographics (e.g. age, body mass index), correct
planned implant size and operative data were not significantly different
between the two groups. The proportion of outliers in the coronal
and sagittal plane ranged from 0% to 21% in both groups. Only the
number of outliers for the posterior slope of the tibial component
showed a significant difference (p = 0.004) with more outliers in
the CT group (n = 9, 13%) than in the MRI group (0%). . Conclusion. The post-operative HKA-axis was comparable in the MRI- and CT-based
PSGs, but there were significantly more outliers for the posterior
slope in the CT-based PSGs. Take home message: Alignment with MRI-based PSG is at least as
good as, if not better, than that of the CT-based PSG, and is the
preferred imaging modality when performing
The extensive variation in axial rotation of tibial components can lead to coronal plane malalignment. We analyzed the change in coronal alignment induced by tray malrotation. We constructed a computer model of knee arthroplasty and used a virtual cutting guide to cut the tibia at 90° to the coronal plane. The virtual guide was rotated axially (15° medial to 15° lateral) and with posterior slopes (0° to 7°). To assess the effect of axial malrotation, we measured the coronal plane alignment of a tibial tray that was axially rotated (25° internal to 15° external), as viewed on a standard anteroposterior (AP) radiograph.Aims
Methods
We evaluated the rates of survival and cause
of revision of seven different brands of cemented primary total
knee replacement (TKR) in the Norwegian Arthroplasty Register during
the years 1994 to 2009. Revision for any cause, including resurfacing
of the patella, was the primary endpoint. Specific causes of revision
were secondary outcomes. Three posterior cruciate-retaining (PCR) fixed modular-bearing
TKRs, two fixed non-modular bearing PCR TKRs and two mobile-bearing
posterior cruciate-sacrificing TKRs were investigated in a total
of 17 782 primary TKRs. The median follow-up for the implants ranged
from 1.8 to 6.9 years. Kaplan-Meier 10-year survival ranged from
89.5% to 95.3%. Cox’s relative risk (RR) was calculated relative
to the fixed modular-bearing Profix knee (the most frequently used
TKR in Norway), and ranged from 1.1 to 2.6. The risk of revision
for aseptic tibial loosening was higher in the mobile-bearing LCS
Classic (RR 6.8 (95% confidence interval (CI) 3.8 to 12.1)), the
LCS Complete (RR 7.7 (95% CI 4.1 to 14.4)), the fixed modular-bearing
Duracon (RR 4.5 (95% CI 1.8 to 11.1)) and the fixed non-modular
bearing AGC Universal
Aims. Total joint arthroplasty (TJA) is commonly performed in elderly
patients. Frailty, an aggregate expression of vulnerability, becomes
increasingly common with advanced age, and independently predicts
adverse outcomes and the use of resources after a variety of non-cardiac
surgical procedures. Our aim was to assess the impact of frailty
on outcomes after TJA. Patients and Methods. We analysed the impact of pre-operative frailty on death and
the use of resources after elective TJA in a population-based cohort
study using linked administrative data from Ontario, Canada. Results. Of 125 163 patients aged >
65 years having elective TJA, 3023
(2.4%) were frail according to the Johns Hopkins ACG frailty-defining
diagnoses indicator. One year follow-up was complete for all patients.
Frail patients had a higher adjusted one year risk of mortality
(hazard ratio 3.03, 95% confidence interval (CI) 2.62 to 3.51),
a higher rate of admission to intensive care (odds ratio (OR) 2.52,
95% CI 2.21 to 2.89), increased length of stay (incidence rate ratio 1.62,
95% CI 1.59 to 1.65), a higher rate of discharge to institutional
care (OR 2.09, 95% CI 1.93 to 2.25), a higher rate of re-admission
(OR 1.33, 95% CI 1.07 to 1.66) and increased costs at 30, 90 and
365 days post-operatively. Frailty affected outcomes after total
hip arthroplasty more than after
Mobile-bearing unicompartmental knee arthroplasty (UKA) with a flat tibial plateau has not performed well in the lateral compartment, leading to a high rate of dislocation. For this reason, the Domed Lateral UKA with a biconcave bearing was developed. However, medial and lateral tibial plateaus have asymmetric anatomical geometries, with a slightly dished medial and a convex lateral plateau. Therefore, the aim of this study was to evaluate the extent at which the normal knee kinematics were restored with different tibial insert designs using computational simulation. We developed three different tibial inserts having flat, conforming, and anatomy-mimetic superior surfaces, whereas the inferior surface in all was designed to be concave to prevent dislocation. Kinematics from four male subjects and one female subject were compared under deep knee bend activity.Aims
Methods
This study aimed to evaluate calprotectin in synovial fluid for diagnosing chronic prosthetic joint infection (PJI) . A total of 63 patients who were suspected of PJI were enrolled. The synovial fluid calprotectin was tested by an enzyme-linked immunosorbent assay (ELISA). Laboratory test data, such as ESR, CRP, synovial fluid white blood cells (SF-WBCs), and synovial fluid polymorphonuclear cells (SF-PMNs), were documented. Chi-squared tests were used to compare the sensitivity and specificity of calprotectin and laboratory tests. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve was calculated to determine diagnostic efficacy.Aims
Methods
The aim of this study was to investigate whether the use of antibiotic-loaded bone cement influenced the risk of revision surgery after primary total hip arthroplasty (THA) for osteoarthritis. The study involved data collected by the National Joint Registry (NJR) for England and Wales, Northern Ireland and the Isle of Man between 1 September 2005 and 31 August 2017. Cox proportional hazards were used to investigate the association between use of antibiotic-loaded bone cement and the risk of revision due to prosthetic joint infection (PJI), with adjustments made for the year of the initial procedure, age at the time of surgery, sex, American Society of Anesthesiologists (ASA) grade, head size, and body mass index (BMI). We looked also at the association between use of antibiotic-loaded bone cement and the risk of revision due to aseptic loosening or osteolysis.Aims
Methods
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. Materials and Methods. Neutrally buoyant bubbles were introduced into the surgical field
of a simulated setup for a routine
To compare the in vivo long-term fixation achieved by two acetabular components with different porous ingrowth surfaces using radiostereometric analysis (RSA). This was a minimum ten-year follow-up of a prospective randomized trial of 62 hips with two different porous ingrowth acetabular components. RSA exams had previously been acquired through two years of follow-up. Patients returned for RSA examination at a minimum of ten years. In addition, radiological appearance of these acetabular components was analyzed, and patient-reported outcome measures (PROMs) obtained.Aims
Methods
Tibial plateau fractures are serious injuries about the knee that have the potential to affect patients’ long-term function. To our knowledge, this is the first study to use patient-reported outcomes (PROs) with a musculoskeletal focus to assess the long-term outcome, as compared to a short-term outcome baseline, of tibial plateau fractures treated using modern techniques. In total, 102 patients who sustained a displaced tibial plateau fracture and underwent operative repair by one of three orthopaedic traumatologists at a large, academic medical centre and had a minimum of five-year follow-up were identified. Breakdown of patients by Schatzker classification is as follows: two (1.9%) Schatzker I, 54 (50.9%) Schatzker II, two (1.9%) Schatzker III, 13 (12.3%) Schatzker IV, nine (8.5%) Schatzker V, and 26 (24.5%) Schatzker VI. Follow-up data obtained included: Visual Analogue Scale (VAS) or Numeric Rating Scale (NRS) pain scores, Short Musculoskeletal Functional Assessment (SMFA), and knee range of movement (ROM). Data at latest follow-up were then compared to 12-month data using a paired Aims
Methods
Primary arthroplasty may be denied to very elderly patients based upon the perceived outcome and risks associated with surgery. This prospective study compared the outcome, complications, and mortality of total hip (TKR) and