The number of revision total knee arthroplasties (TKA) that are
performed is expected to increase. However, previous reports of
the causes of failure after TKA are limited in that they report
the causes at specific institutions, which are often dependent on
referral patterns. Our aim was to report the most common indications
for re-operations and revisions in a large series of posterior-stabilised
TKAs undertaken at a single institution, excluding referrals from
elsewhere, which may bias the causes of failure. A total of 5098 TKAs which were undertaken between 2000 and 2012
were included in the study. Re-operations, revisions with modular
component exchange, and revisions with non-modular component replacement
or removal were identified from the medical records. The mean follow-up
was five years (two to 12).Aims
Patients and Methods
This study describes the use of the Masquelet technique to treat
segmental tibial bone loss in 12 patients. This retrospective case series reviewed 12 patients treated between
2010 and 2015 to determine their clinical outcome. Patients were
mostly male with a mean age of 36 years (16 to 62). The outcomes
recorded included union, infection and amputation. The mean follow-up
was 675 days (403 to 952). Aims
Patients and Methods
Analysis of the morphology of the distal femur, and by extension
of the femoral components in total knee arthroplasty (TKA), has
largely been related to the aspect ratio, which represents the width
of the femur. Little is known about variations in trapezoidicity
(i.e. whether the femur is more rectangular or more trapezoidal).
This study aimed to quantify additional morphological characteristics
of the distal femur and identify anatomical features associated
with higher risks of over- or under-sizing of components in TKA. We analysed the shape of 114 arthritic knees at the time of primary
TKA using the pre-operative CT scans. The aspect ratio and trapezoidicity
ratio were quantified, and the post-operative prosthetic overhang
was calculated. We compared the morphological characteristics with
those of 12 TKA models.Aims
Methods
Static radiostereometric analysis (RSA) using implanted markers is considered the most accurate system for the evaluation of prosthesis migration. By using CT bone models instead of markers, combined with a dynamic RSA system, a non-invasive measurement of joint movement is enabled. This method is more accurate than current 3D skin marker-based tracking systems. The purpose of this study was to evaluate the accuracy of the CT model method for measuring knee joint kinematics in static and dynamic RSA using the marker method as the benchmark. Bone models were created from CT scans, and tantalum beads were implanted into the tibia and femur of eight human cadaver knees. Each specimen was secured in a fixture, static and dynamic stereoradiographs were recorded, and the bone models and marker models were fitted to the stereoradiographs.Objectives
Methods
Primary total knee arthroplasty (TKA) is a reliable
procedure with reproducible long-term results. Nevertheless, there
are conditions related to the type of patient or local conditions
of the knee that can make it a difficult procedure. The most common
scenarios that make it difficult are discussed in this review. These
include patients with many previous operations and incisions, and
those with severe coronal deformities, genu recurvatum, a stiff knee,
extra-articular deformities and those who have previously undergone
osteotomy around the knee and those with chronic dislocation of
the patella. Each condition is analysed according to the characteristics of
the patient, the pre-operative planning and the reported outcomes. When approaching the difficult primary TKA surgeons should use
a systematic approach, which begins with the review of the existing
literature for each specific clinical situation. Cite this article:
The use of robotics in arthroplasty surgery is expanding rapidly as improvements in the technology evolve. This article examines current evidence to justify the usage of robotics, as well as the future potential in this emerging field.
We studied whether the presence of lateral osteophytes
on plain radiographs was a predictor for the quality of cartilage
in the lateral compartment of patients with varus osteoarthritic
of the knee (Kellgren and Lawrence grade 2 to 3). The baseline MRIs of 344 patients from the Osteoarthritis Initiative
(OAI) who had varus osteoarthritis (OA) of the knee on hip-knee-ankle
radiographs were reviewed. Patients were categorised using the Osteoarthritis
Research Society International (OARSI) osteophyte grading system
into 174 patients with grade 0 (no osteophytes), 128 grade 1 (mild
osteophytes), 28 grade 2 (moderate osteophytes) and 14 grade 3 (severe
osteophytes) in the lateral compartment (tibia). All patients had
Kellgren and Lawrence grade 2 or 3 arthritis of the medial compartment.
The thickness and volume of the lateral cartilage and the percentage
of full-thickness cartilage defects in the lateral compartment was
analysed. There was no difference in the cartilage thickness or cartilage
volume between knees with osteophyte grades 0 to 3. The percentage
of full-thickness cartilage defects on the tibial side increased
from <
2% for grade 0 and 1 to 10% for grade 3. The lateral compartment cartilage volume and thickness is not
influenced by the presence of lateral compartment osteophytes in
patients with varus OA of the knee. Large lateral compartment osteophytes
(grade 3) increase the likelihood of full-thickness cartilage defects
in the lateral compartment. Cite this article:
To evaluate the hypothesis that failed osteosynthesis of periprosthetic
Vancouver type B1 fractures can be treated successfully with stem
revision using a transfemoral approach and a cementless, modular,
tapered revision stem with reproducible rates of fracture healing,
stability of the revision stem, and clinically good results. A total of 14 patients (11 women, three men) with a mean age
of 72.4 years (65 to 90) undergoing revision hip arthroplasty after
failed osteosynthesis of periprosthetic fractures of Vancouver type
B1 were treated using a transfemoral approach to remove the well-fixed
stem before insertion of a modular, fluted titanium stem which obtained
distal fixation. These patients were clinically and radiologically
followed up for a mean 52.2 months (24 to 144).Aims
Patients and Methods
The purpose of this study was to analyse the biomechanics of
walking, through the ground reaction forces (GRF) measured, after
first metatarsal osteotomy or metatarsophalangeal joint (MTP) arthrodesis. A total of 19 patients underwent a Scarf osteotomy (50.3 years,
standard deviation (Aims
Patients and Methods
We evaluated the accuracy of augmented reality (AR)-based navigation assistance through simulation of bone tumours in a pig femur model. We developed an AR-based navigation system for bone tumour resection, which could be used on a tablet PC. To simulate a bone tumour in the pig femur, a cortical window was made in the diaphysis and bone cement was inserted. A total of 133 pig femurs were used and tumour resection was simulated with AR-assisted resection (164 resection in 82 femurs, half by an orthropaedic oncology expert and half by an orthopaedic resident) and resection with the conventional method (82 resection in 41 femurs). In the conventional group, resection was performed after measuring the distance from the edge of the condyle to the expected resection margin with a ruler as per routine clinical practice.Objectives
Methods
This prospective study reports the 15-year survival and ten-year
functional outcome of a consecutive series of 1000 minimally invasive
Phase 3 Oxford medial UKAs (818 patients, 393 men, 48%, 425 women,
52%, mean age 66 years; 32 to 88). These were implanted by two surgeons
involved with the design of the prosthesis to treat anteromedial
osteoarthritis and spontaneous osteonecrosis of the knee, which
are recommended indications. Patients were prospectively identified
and followed up independently for a mean of 10.3 years (5.3 to 16.6). At ten years, the mean Oxford Knee Score was 40 (standard deviation
( This is the only large series of minimally invasive UKAs with
15-year survival data. The results support the continued use of
minimally invasive UKA for the recommended indications. Cite this article:
We describe our technique and rationale using
hybrid fixation for primary total hip arthroplasty (THA) at the Hospital
for Special Surgery. Modern uncemented acetabular components have
few screw holes, or no holes, polished inner surfaces, improved
locking mechanisms, and maximised thickness and shell-liner conformity. Uncemented
sockets can be combined with highly cross-linked polyethylene liners,
which have demonstrated very low wear and osteolysis rates after
ten to 15 years of implantation. The results of cement fixation
with a smooth or polished surface finished stem have been excellent,
virtually eliminating complications seen with cementless fixation
like peri-operative femoral fractures and thigh pain. Although mid-term
results of modern cementless stems are encouraging, the long-term
data do not show reduced revision rates for cementless stems compared
with cemented smooth stems. In this paper we review the conduct
of a hybrid THA, with emphasis on pre-operative planning, surgical
technique, hypotensive epidural anaesthesia, and intra-operative
physiology. Cite this article:
The accurate reconstruction of hip anatomy and
biomechanics is thought to be important in achieveing good clinical
outcomes following total hip arthroplasty (THA). To this end some
newer hip designs have introduced further modularity into the design
of the femoral component such that neckshaft angle and anteversion,
which can be adjusted intra-operatively. The clinical effect of
this increased modularity is unknown. We have investigated the changes
in these anatomical parameters following conventional THA with a
prosthesis of predetermined neck–shaft angle and assessed the effect
of changes in the hip anatomy on clinical outcomes. In total, 44 patients (mean age 65.3 years (standard deviation
( The mean pre-operative neck–shaft angle was significantly increased
by 2.8° from 128° ( Cite this article:
The aims of this study were: firstly, to investigate the influence
of the thickness of cartilage at the sigmoid notch on the inclination
of the distal radioulnar joint (DRUJ), and secondly, to compare
the sensitivity and specificity of MRI with plain radiographs for
the assessment of the inclination of the articular surface of the
DRUJ in the coronal plane. Contemporaneous MRI images and radiographs of 100 wrists from
98 asymptomatic patients (mean age 43 years, (16 to 67); 52 male,
53%) with no history of a fracture involving the wrist or surgery
to the wrist, were reviewed. The thickness of the cartilage at the
sigmoid notch, inclination of the DRUJ and Tolat Type of each DRUJ
were determined. Aims
Patients and Methods
This study aimed to determine the long-term functional,
clinical and radiological outcomes in patients with Schatzker IV
to VI fractures of the tibial plateau treated with an Ilizarov frame.
Clinical, functional and radiological assessment was carried out
at a minimum of one year post-operatively. A cohort of 105 patients
(62 men, 43 women) with a mean age of 49 years (15 to 87) and a
mean follow-up of 7.8 years (1 to 19) were reviewed. There were
18 type IV, 10 type V and 77 type VI fractures. All fractures united
with a mean time to union of 20.1 weeks (10.6 to 42.3). No patient
developed a deep infection. The median range of movement (ROM) of
the knee was 110o and the median Iowa score was 85. Our study demonstrates good long-term functional outcome with
no deep infection; spanning the knee had no detrimental effect on
the ROM or functional outcome. High-energy fractures of the tibial plateau may be treated effectively
with a fine wire Ilizarov fixator. Cite this article:
The present study describes a novel technique for revitalising allogenic intrasynovial tendons by combining cell-based therapy and mechanical stimulation in an Specifically, canine flexor digitorum profundus tendons were used for this study and were divided into the following groups: (1) untreated, unprocessed normal tendon; (2) decellularised tendon; (3) bone marrow stromal cell (BMSC)-seeded tendon; and (4) BMSC-seeded and cyclically stretched tendon. Lateral slits were introduced on the tendon to facilitate cell seeding. Tendons from all four study groups were distracted by a servohydraulic testing machine. Tensile force and displacement data were continuously recorded at a sample rate of 20 Hz until 200 Newton of force was reached. Before testing, the cross-sectional dimensions of each tendon were measured with a digital caliper. Young’s modulus was calculated from the slope of the linear region of the stress-strain curve. The BMSCs were labeled for histological and cell viability evaluation on the decellularized tendon scaffold under a confocal microscope. Gene expression levels of selected extracellular matrix tendon growth factor genes were measured. Results were reported as mean ± SD and data was analyzed with one-way ANOVAs followed by Tukey’s post hoc multiple-comparison test.Objectives
Methods
The use of robots in orthopaedic surgery is an
emerging field that is gaining momentum. It has the potential for significant
improvements in surgical planning, accuracy of component implantation
and patient safety. Advocates of robot-assisted systems describe
better patient outcomes through improved pre-operative planning
and enhanced execution of surgery. However, costs, limited availability,
a lack of evidence regarding the efficiency and safety of such systems
and an absence of long-term high-impact studies have restricted
the widespread implementation of these systems. We have reviewed
the literature on the efficacy, safety and current understanding of
the use of robotics in orthopaedics. Cite this article:
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