Unicompartmental knee arthroplasty (UKA) has
numerous advantages over total knee arthroplasty (TKA) and one disadvantage,
the higher revision rate. The best way to minimize the revision
rate is for surgeons to use UKA for at least 20% of their knee arthroplasties.
To achieve this, they need to learn and apply the appropriate indications
and techniques. This would decrease the revision rate and increase
the number of UKAs which were implanted, which would save money
and patients would benefit from improved outcomes over their lifetime. Cite this article:
Primary (or spontaneous) and secondary osteonecrosis of the knee
can lead to severe joint degeneration, for which either total or
unicompartmental arthroplasty may be considered. However, there
are limited studies analyzing outcomes of unicompartmental knee arthroplasties
(UKAs) for osteonecrosis involving an isolated compartment of the
knee. The aims of this study were to analyze outcomes of UKAs for
osteonecrosis with specific focus on 1) survivorship free of any
revision or reoperation, 2) risk factors for failure, 3) clinical outcomes,
and 4) complications. A total of 45 patients underwent 46 UKAs for knee osteonecrosis
between 2002 and 2014 at our institution (The Mayo Clinic, Rochester,
Minnesota). Twenty patients (44%) were female; the mean age of the
patients was 66 years, and mean body mass index (BMI) was 31 kg/m2. Of
the 46 UKAs, 44 (96%) were medial UKAs, and 35 (76%) were fixed-bearing
design. Mean mechanical axis postoperatively was 1.5° varus (0°
to 5° varus); 41 UKAs (89%) were performed for primary osteonecrosis.
Mean follow-up was five years (2 to 12)Aims
Patients and Methods
The primary stability of the cementless Oxford Unicompartmental Knee Replacement (OUKR) relies on interference fit (or press fit). Insufficient interference may cause implant loosening, whilst excessive interference could cause bone damage and fracture. The aim of this study was to identify the optimal interference fit by measuring the force required to seat the tibial component of the cementless OUKR (push-in force) and the force required to remove the component (pull-out force). Six cementless OUKR tibial components were implanted in 12 new slots prepared on blocks of solid polyurethane foam (20 pounds per cubic foot (PCF), Sawbones, Malmo, Sweden) with a range of interference of 0.1 mm to 1.9 mm using a Dartec materials testing machine HC10 (Zwick Ltd, Herefordshire, United Kingdom) . The experiment was repeated with cellular polyurethane foam (15 PCF), which is a more porous analogue for trabecular bone.Objectives
Materials and Methods
Infection following total hip or knee arthroplasty is a serious
complication. We noted an increase in post-operative infection in
cases carried out in temporary operating theatres. We therefore
compared those cases performed in standard and temporary operating
theatres and examined the deep periprosthetic infection rates. A total of 1223 primary hip and knee arthroplasties were performed
between August 2012 and June 2013. A total of 539 (44%) were performed
in temporary theatres. The two groups were matched for age, gender,
body mass index and American Society of Anesthesiologists grade.Aims
Patients and methods
The aim of this study was to investigate the outcomes of Vancouver
type B2 and B3 fractures by performing a systematic review of the
methods of surgical treatment which have been reported. A systematic search was performed in Ovid MEDLINE, Embase and
the Cochrane Central Register of Controlled Trials. For inclusion,
studies required a minimum of ten patients with a Vancouver type
B2 and/or ten patients with a Vancouver type B3 fracture, a minimum
mean follow-up of two years and outcomes which were matched to the type
of fracture. Studies were also required to report the rate of re-operation
as an outcome measure. The protocol was registered in the PROSPERO
database. Aims
Materials and Methods
The aim of this study was to evaluate the long-term inducible
displacement of cemented tibial components ten years after total
knee arthroplasty (TKA). A total of 15 patients from a previously reported prospective
trial of fixation using radiostereometric analysis (RSA) were examined
at a mean of 11 years (10 to 11) postoperatively. Longitudinal supine
RSA examinations were acquired at one week, one year, and two years
postoperatively and at final follow-up. Weight-bearing RSA examinations
were also undertaken with the operated lower limb in neutral and
in maximum internal rotation positions. Maximum total point motion
(MTPM) was calculated for the longitudinal and inducible displacement examinations
(supine Aims
Patients and Methods
To present a surgically relevant update of trunnionosis. Systematic review performed April 2017.Aims
Materials and Methods
The number of arthroplasties of the hip and knee
is predicted to increase rapidly during the next 20 years. Accompanying
this is the dilemma of how to follow-up these patients appropriately.
Current guidelines recommend long-term follow-up to identify patients
with aseptic loosening, which can occur more than a decade postoperatively.
The current guidelines and practices of orthopaedic surgeons vary
widely. Existing models take up much clinical time and are expensive.
Pilot studies using ‘virtual’ clinics and advanced-practice physiotherapists
have shown promise in decreasing the time and costs for orthopaedic surgeons
and patients. This review discusses current practices and future trends in
the follow-up of patients who have an arthroplasty. Cite this article:
The outcome of total knee arthroplasty (TKA) is not always satisfactory.
The purpose of this study was to identify satisfaction and biomechanical
features characterising the gait of patients who had undergone TKA
with either an anatomical single radius design or a medial pivot
design. We hypothesised that the latter would provide superior function. This is a study of a subset of patients recruited into a prospective
randomised study of a single radius design Aims
Patients and Methods