The purpose of this investigation was to determine the relationship between height, weight, and sex with implant size in total knee arthroplasty (TKA) using a multivariate linear regression model and a Bayesian model. A retrospective review of an institutional registry was performed of primary TKAs performed between January 2005 and December 2016. Patient demographics including patient age, sex, height, weight, and body mass index (BMI) were obtained from registry and medical record review. In total, 8,100 primary TKAs were included. The mean age was 67.3 years (SD 9.5) with a mean BMI of 30.4 kg/m2 (SD 6.3). The TKAs were randomly split into a training cohort (n = 4,022) and a testing cohort (n = 4,078). A multivariate linear regression model was created on the training cohort and then applied to the testing cohort . A Bayesian model was created based on the frequencies of implant sizes in the training cohort. The model was then applied to the testing cohort to determine the accuracy of the model at 1%, 5%, and 10% tolerance of inaccuracy.Aims
Methods
Stiffness is a common complication after total knee arthroplasty (TKA). Pathogenesis is not understood, treatment options are limited, and diagnosis is challenging. The aim of this study was to investigate if MRI can be used to visualize intra-articular scarring in patients with stiff, painful knee arthroplasties. Well-functioning primary TKAs (n = 11), failed non-fibrotic TKAs (n = 5), and patients with a clinical diagnosis of fibrosisAims
Methods
To compare patients undergoing total knee arthroplasty (TKA) with ≤ 80° range of movement (ROM) operated with a 2 mm increase in the flexion gap with matched non-stiff patients with at least 100° of preoperative ROM and balanced flexion and extension gaps. In a retrospective cohort study, 98 TKAs (91 patients) with a preoperative ROM of ≤ 80° were examined. Mean follow-up time was 53 months (24 to 112). All TKAs in stiff knees were performed with a 2 mm increased flexion gap. Data were compared to a matched control group of 98 TKAs (86 patients) with a mean follow-up of 43 months (24 to 89). Knees in the control group had a preoperative ROM of at least 100° and balanced flexion and extension gaps. In all stiff and non-stiff knees posterior stabilized (PS) TKAs with patellar resurfacing in combination with adequate soft tissue balancing were used.Aims
Methods
The early diagnosis of aseptic
In 2005, we demonstrated that the polished triple-tapered
C-stem at two years had migrated distally and rotated internally.
From that series, 33 patients have now been followed radiologically,
clinically and by radiostereometric analysis (RSA) for up to ten
years. The distal migration within the cement mantle had continued
and reached a mean of 2 mm (0.5 to 4.0) at ten years. Internal rotation,
also within the cement mantle, was a mean 3.8° (external 1.6° to
internal 6.6°) The cement mantle did not show any sign of migration
or
We reviewed 120 consecutive primary total hip replacements in 109 patients in whom a Freeman uncemented metal-backed component had been used. Acetabular components were used with a Freeman neck-retaining stem in one of three configurations: cemented smooth stem, uncemented smooth stem or uncemented ridged stem. After a mean follow up of 72 months (62 to 113) there were nine cases of aseptic
Dislocation remains a significant complication after total hip arthroplasty (THA), being the third leading indication for revision. We present a series of acetabular revision using a dual mobility cup (DMC) and compare this with our previous series using the posterior lip augmentation device (PLAD). A retrospective review of patients treated with either a DMC or PLAD for dislocation in patients with a Charnley THA was performed. They were identified using electronic patient records (EPR). EPR data and radiographs were evaluated to determine operating time, length of stay, and the incidence of complications and recurrent dislocation postoperatively.Aims
Methods
Peri-acetabular tumour resections and their subsequent
reconstruction are among the most challenging procedures in orthopaedic
oncology. Despite the fact that a number of different pelvic endoprostheses
have been introduced, rates of complication remain high and long-term
results are mostly lacking. . In this retrospective study, we aimed to evaluate the outcome
of reconstructing a peri-acetabular defect with a pedestal cup endoprosthesis
after a type 2 or type 2/3 internal hemipelvectomy. A total of 19 patients (11M:8F) with a mean age of 48 years (14
to 72) were included, most of whom had been treated for a primary
bone tumour (n = 16) between 2003 and 2009. After a mean follow-up
of 39 months (28 days to 8.7 years) seven patients had died. After
a mean follow-up of 7.9 years (4.3 to 10.5), 12 patients were alive,
of whom 11 were disease-free. Complications occurred in 15 patients.
Three had recurrent dislocations and three experienced aseptic
Impaction bone grafting for the reconstitution
of bone stock in revision hip surgery has been used for nearly 30 years.
Between 1995 and 2001 we used this technique in acetabular reconstruction,
in combination with a cemented component, in 304 hips in 292 patients
revised for aseptic
Dual mobility (DM) bearings are an attractive treatment option to obtain hip stability during challenging primary and revision total hip arthroplasty (THA) cases. The purpose of this study was to analyze data submitted to the American Joint Replacement Registry (AJRR) to characterize utilization trends of DM bearings in the USA. All primary and revision THA procedures reported to AJRR from 2012 to 2018 were analyzed. Patients of all ages were included and subdivided into DM and traditional bearing surface cohorts. Patient demographics, geographical region, hospital size, and teaching affiliation were assessed. Associations were determined by chi-squared analysis and logistic regression was performed to assess outcome variables.Aims
Methods
We conducted a systematic review and meta-analysis to compare the mortality, morbidity, and functional outcomes of cemented versus uncemented hemiarthroplasty in the treatment of intracapsular hip fractures, analyzing contemporary and non-contemporary implants separately. PubMed, Medline, EMBASE, CINAHL, and Cochrane Library were searched to 2 February 2020 for randomized controlled trials (RCTs) comparing the primary outcome, mortality, and secondary outcomes of function, quality of life, reoperation, postoperative complications, perioperative outcomes, pain, and length of hospital stay. Relative risks (RRs) and mean differences (with 95% confidence intervals (CIs)) were used as summary association measures.Aims
Methods
We aimed to examine the long-term mechanical survivorship, describe the modes of all-cause failure, and identify risk factors for mechanical failure of all-polyethylene tibial components in endoprosthetic reconstruction. This is a retrospective database review of consecutive endoprosthetic reconstructions performed for oncological indications between 1980 and 2019. Patients with all-polyethylene tibial components were isolated and analyzed for revision for mechanical failure. Outcomes included survival of the all-polyethylene tibial component, revision surgery categorized according to the Henderson Failure Mode Classification, and complications and functional outcome, as assessed by the Musculoskeletal Tumor Society (MSTS) score at the final follow-up.Aims
Methods
Review of the radiographs of 882 consecutive metal-to-polyethylene hip replacements after a mean follow-up of 6.8 years showed 72 cases (8%) of aseptic femoral
Large femoral heads have become popular in total
hip replacement (THR) as a method of reducing the risk of dislocation.
However, if large heads are used in ceramic-on-ceramic THR, the
liner must be thinner, which may increase the risk of fracture.
To compare the rates of ceramic fracture and dislocation between
28 mm and 32 mm ceramic heads, 120 hips in 109 patients (51 men
and 58 women, mean age 49.2 years) were randomised to THR with either
a 28 mm or a 32 mm ceramic articulation. A total of 57/60 hips assigned
to the 28 mm group and 55/60 hips assigned to the 32 mm group were
followed for at least five years. No ceramic component fractures
occured in any patient in either group. There was one dislocation
in the 32 mm group and none in the 28 mm group (p = 0.464). No hip
had detectable wear, focal osteolysis or prosthetic
Our objective is to describe our early and mid-term results with the use of a new simple primary knee prosthesis as an articulating spacer in planned two-stage management for infected knee arthroplasty. As a second objective, we compared outcomes between the group with a retained first stage and those with a complete two-stage revision. We included 47 patients (48 knees) with positive criteria for infection, with a minimum two-year follow-up, in which a two-stage approach with an articulating spacer with new implants was used. Patients with infection control, and a stable and functional knee were allowed to retain the initial first-stage components. Outcomes recorded included: infection control rate, reoperations, final range of motion (ROM), and quality of life assessment (QoL) including Western Ontario and McMaster Universities osteoarthritis index, Knee Injury and Osteoarthritis Outcome Score, Oxford Knee Score, 12-Item Short-Form Health Survey questionnaire, and University of California Los Angeles (UCLA) activity score and satisfaction score. These outcomes were evaluated and compared to additional cohorts of patients with retained first-stage interventions and those with a complete two-stage revision. Mean follow-up was 3.7 years (2.0 to 6.5).Aims
Methods
PCL retaining fixed-bearing TKA is a highly successful
operation with the need for more surgery occurring at the rate of
approximately 0.4% per year over the first 27 years. The most common
cause for revision surgery is related to polyethylene insert failure
and accounts for approximately 50% of re-operations. Late metastatic
infection is the next most frequent cause followed by patellar problems,
late instability and component
Bone loss in the proximal tibia and distal femur
is frequently encountered in revision knee replacement surgery.
The various options for dealing with this depend on the extent of
any bone loss. We present our results with the use of cementless
metaphyseal metal sleeves in 103 patients (104 knees) with a mean
follow-up of 43 months (30 to 65). At final follow-up, sleeves in
102 knees had good osseointegration. Two tibial sleeves were revised
for
We made a retrospective study of 55 primary total hip arthroplasties in 53 patients with a history of previous acetabular fracture. The mean follow-up was 7.5 years and the average age at fracture was 48.7 years. The incidence of radiographic femoral
We reviewed at a minimum elapsed time of five years a consecutive series of 143 primary Exeter hip replacements in which matt-surfaced femoral stems had been used. Twenty-five patients had died and six stems and two sockets had been revised before follow-up. The remaining 110 hips were all examined clinically and radiographically. In 15 hips there were radiographic signs of definite