This study compares the PFC total knee arthroplasty (TKA) system in a prospective randomized control trial (RCT) of the mobile-bearing rotating-platform (RP) TKA against the fixed-bearing (FB) TKA. This is the largest RCT with the longest follow-up where cruciate-retaining PFC total knee arthroplasties are compared in a non-bilateral TKA study. A total of 167 patients (190 knees with 23 bilateral cases), were recruited prospectively and randomly assigned, with 91 knees receiving the RP and 99 knees receiving FB. The mean age was 65.5 years (48 to 82), the mean body mass index (BMI) was 29.7 kg/m2 (20 to 52) and 73 patients were female. The Knee Society Score (KSS), Knee Society Functional Score (KSFS), Oxford Knee Score (OKS), Western Ontario and McMaster Universities Arthritis Index (WOMAC), and 12-Item Short-Form Health Survey Physical and Mental Component Scores (SF-12 PCS, SF-12 MCS) were gathered and recorded preoperatively, at five-years’ follow-up, and at ten years’ follow-up. Additionally, Knee Injury and Osteoarthritis Outcome Scores (KOOS) were collected at five- and ten-year follow-ups. The prevalence of radiolucent lines (RL) on radiographs and implant survival were recorded at five- and ten-year follow-ups.Aims
Patients and Methods
The primary aim of this study was to compare the knee-specific functional outcome of patellofemoral arthroplasty with total knee arthroplasty (TKA) in the management of patients with patellofemoral osteoarthritis. A total of 54 consecutive Avon patellofemoral arthroplasties were identified and propensity-score-matched to a group of 54 patients undergoing a TKA with patellar resurfacing for patellofemoral osteoarthritis. The Oxford Knee Score (OKS), the 12-Item Short-Form Health Survey (SF-12), and patient satisfaction were collected at a mean follow up of 9.2 years (8 to 15). Survival was defined by revision or intention to revise.Aims
Patients and Methods
This study reports on a secondary exploratory analysis of the early clinical outcomes of a randomised clinical trial comparing robotic arm-assisted unicompartmental knee arthroplasty (UKA) for medial compartment osteoarthritis of the knee with manual UKA performed using traditional surgical jigs. This follows reporting of the primary outcomes of implant accuracy and gait analysis that showed significant advantages in the robotic arm-assisted group. A total of 139 patients were recruited from a single centre. Patients were randomised to receive either a manual UKA implanted with the aid of traditional surgical jigs, or a UKA implanted with the aid of a tactile guided robotic arm-assisted system. Outcome measures included the American Knee Society Score (AKSS), Oxford Knee Score (OKS), Forgotten Joint Score, Hospital Anxiety Depression Scale, University of California at Los Angeles (UCLA) activity scale, Short Form-12, Pain Catastrophising Scale, somatic disease (Primary Care Evaluation of Mental Disorders Score), Pain visual analogue scale, analgesic use, patient satisfaction, complications relating to surgery, 90-day pain diaries and the requirement for revision surgery.Objectives
Methods
Posterior condylar offset (PCO) and posterior tibial slope (PTS) are critical factors in total knee arthroplasty (TKA). A computational simulation was performed to evaluate the biomechanical effect of PCO and PTS on cruciate retaining TKA. We generated a subject-specific computational model followed by the development of ± 1 mm, ± 2 mm and ± 3 mm PCO models in the posterior direction, and -3°, 0°, 3° and 6° PTS models with each of the PCO models. Using a validated finite element (FE) model, we investigated the influence of the changes in PCO and PTS on the contact stress in the patellar button and the forces on the posterior cruciate ligament (PCL), patellar tendon and quadriceps muscles under the deep knee-bend loading conditions.Objectives
Methods
Little biomechanical information is available about kinematically aligned (KA) total knee arthroplasty (TKA). The purpose of this study was to simulate the kinematics and kinetics after KA TKA and mechanically aligned (MA) TKA with four different limb alignments. Bone models were constructed from one volunteer (normal) and three patients with three different knee deformities (slight, moderate and severe varus). A dynamic musculoskeletal modelling system was used to analyse the kinematics and the tibiofemoral contact force. The contact stress on the tibial insert, and the stress to the resection surface and medial tibial cortex were examined by using finite element analysis.Objectives
Materials and Methods
The aim of this study was to evaluate the surface damage, the density of crosslinking, and oxidation in retrieved antioxidant-stabilized highly crosslinked polyethylene (A-XLPE) tibial inserts from total knee arthroplasty (TKA), and to compare the results with a matched cohort of standard remelted highly crosslinked polyethylene (XLPE) inserts. A total of 19 A-XLPE tibial inserts were retrieved during revision TKA and matched to 18 retrieved XLPE inserts according to the demographics of the patients, with a mean length of implantation of 15 months (1 to 42). The percentage areas of PE damage on the articular surfaces and the modes of damage were measured. The density of crosslinking of the PE and oxidation were measured at loaded and unloaded regions on these surfaces.Aims
Materials and Methods
Tibiofemoral alignment is important to determine the rate of
progression of osteoarthritis and implant survival after total knee
arthroplasty (TKA). Normally, surgeons aim for neutral tibiofemoral
alignment following TKA, but this has been questioned in recent
years. The aim of this study was to evaluate whether varus or valgus
alignment indeed leads to increased medial or lateral tibiofemoral
forces during static and dynamic weight-bearing activities. Tibiofemoral contact forces and moments were measured in nine
patients with instrumented knee implants. Medial force ratios were
analysed during nine daily activities, including activities with
single-limb support (e.g. walking) and double-limb support (e.g.
knee bend). Hip-knee-ankle angles in the frontal plane were analysed
using full-leg coronal radiographs. Aims
Patients and Methods
The use of a noninvasive growing endoprosthesis in the management
of primary bone tumours in children is well established. However,
the efficacy of such a prosthesis in those requiring a revision
procedure has yet to be established. The aim of this series was
to present our results using extendable prostheses for the revision
of previous endoprostheses. All patients who had a noninvasive growing endoprosthesis inserted
at the time of a revision procedure were identified from our database.
A total of 21 patients (seven female patients, 14 male) with a mean
age of 20.4 years (10 to 41) at the time of revision were included.
The indications for revision were mechanical failure, trauma or infection
with a residual leg-length discrepancy. The mean follow-up was 70
months (17 to 128). The mean shortening prior to revision was 44 mm
(10 to 100). Lengthening was performed in all but one patient with
a mean lengthening of 51 mm (5 to 140).Aims
Patients and Methods
Total ankle arthroplasty (TAA) surgery is complex and attracts a wide variety of complications. The literature lacks consistency in reporting adverse events and complications. The aim of this article is to provide a comprehensive analysis of each of these complications from a literature review, and to compare them with rates from our Unit, to aid clinicians with the process of informed consent. A total of 278 consecutive total ankle arthroplasties (251 patients), performed by four surgeons over a six-year period in Wrightington Hospital (Wigan, United Kingdom) were prospectively reviewed. There were 143 men and 108 women with a mean age of 64 years (41 to 86). The data were recorded on each follow-up visit. Any complications either during initial hospital stay or subsequently reported on follow-ups were recorded, investigated, monitored, and treated as warranted. Literature search included the studies reporting the outcomes and complications of TAA implants.Aims
Patients and Methods
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. 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).Aims
Patients and Methods
A failed total ankle arthroplasty (TAA) is often associated with
much bone loss. As an alternative to arthrodesis, the surgeon may
consider a custom-made talar component to compensate for the bone
loss. Our aim in this study was to assess the functional and radiological
outcome after the use of such a component at mid- to long-term follow-up. A total of 12 patients (five women and seven men, mean age 53
years; 36 to77) with a failed TAA and a large talar defect underwent
a revision procedure using a custom-made talar component. The design
of the custom-made components was based on CT scans and standard
radiographs, when compared with the contralateral ankle. After the
anterior talocalcaneal joint was fused, the talar component was
introduced and fixed to the body of the calcaneum.Aims
Patients and Methods
As the number of younger and more active patients
treated with total knee arthroplasty (TKA) continues to increase,
consideration of better fixation as a means of improving implant
longevity is required. Cemented TKA remains the reference standard
with the largest body of evidence and the longest follow-up to support
its use. However, cementless TKA, may offer the opportunity of a
more bone-sparing procedure with long lasting biological fixation
to the bone. We undertook a review of the literature examining advances
of cementless TKA and the reported results. Cite this article:
The last decade has seen a considerable increase
in the use of in total ankle arthroplasty (TAA) to treat patients
with end-stage arthritis of the ankle. However, the longevity of
the implants is still far from that of total knee and hip arthroplasties. The aim of this review is to outline a diagnostic and treatment
algorithm for the painful TAA to be used when considering revision
surgery. Cite this article: