The objective of this study was to compare simulated range of motion (ROM) for reverse total shoulder arthroplasty (rTSA) with and without adjustment for scapulothoracic orientation in a global reference system. We hypothesized that values for simulated ROM in preoperative planning software with and without adjustment for scapulothoracic orientation would be significantly different. A statistical shape model of the entire humerus and scapula was fitted into ten shoulder CT scans randomly selected from 162 patients who underwent rTSA. Six shoulder surgeons independently planned a rTSA in each model using prototype development software with the ability to adjust for scapulothoracic orientation, the starting position of the humerus, as well as kinematic planes in a global reference system simulating previously described posture types A, B, and C. ROM with and without posture adjustment was calculated and compared in all movement planes.Aims
Methods
Manual impaction, with a mallet and introducer, remains the standard method of installing cementless acetabular cups during total hip arthroplasty (THA). This study aims to quantify the accuracy and precision of manual impaction strikes during the seating of an acetabular component. This understanding aims to help improve impaction surgical techniques and inform the development of future technologies. Posterior approach THAs were carried out on three cadavers by an expert orthopaedic surgeon. An instrumented mallet and introducer were used to insert cementless acetabular cups. The motion of the mallet, relative to the introducer, was analyzed for a total of 110 strikes split into low-, medium-, and high-effort strikes. Three parameters were extracted from these data: strike vector, strike offset, and mallet face alignment.Aims
Methods
Despite limited clinical scientific backing, an additional trochanteric stabilizing plate (TSP) has been advocated when treating unstable trochanteric fractures with a sliding hip screw (SHS). We aimed to explore whether the TSP would result in less post operative fracture motion, compared to SHS alone. Overall, 31 patients with AO/OTA 31-A2 trochanteric fractures were randomized to either a SHS alone or a SHS with an additional TSP. To compare postoperative fracture motion, radiostereometric analysis (RSA) was performed before and after weightbearing, and then at four, eight, 12, 26, and 52 weeks. With the “after weightbearing” images as baseline, we calculated translations and rotations, including shortening and medialization of the femoral shaft.Aims
Methods
The aim of this study was to assess and compare active rotation of the forearm in normal subjects after the application of a short-arm cast (SAC) in the semisupination position and a long-arm cast (LAC) in the neutral position. A clinical study was also conducted to compare the functional outcomes of using a SAC in the semisupination position with those of using a LAC in the neutral position in patients who underwent arthroscopic triangular fibrocartilage complex (TFCC) foveal repair. A total of 40 healthy right-handed volunteers were recruited. Active pronation and supination of the forearm were measured in each subject using a goniometer. In the retrospective clinical study, 40 patients who underwent arthroscopic foveal repair were included. The wrist was immobilized postoperatively using a SAC in the semisupination position (approximately 45°) in 16 patients and a LAC in 24. Clinical outcomes were assessed using grip strength and patient-reported outcomes. The degree of disability caused by cast immobilization was also evaluated when the cast was removed.Aims
Methods
The aim of this study was to conduct the largest low contact stress (LCS) retrieval study to elucidate the failure mechanisms of the Porocoat and Duofix femoral component. The latter design was voluntarily recalled by the manufacturer. Uncemented LCS explants were divided into three groups: Duofix, Porocoat, and mixed. Demographics, polyethylene wear, tissue ingrowth, and metallurgical analyses were performed.Aims
Materials and Methods
Aims
Patients and Methods
Scapular notching is a frequently observed radiographic phenomenon
in reverse shoulder arthroplasty (RSA), signifying impingement of
components. The purposes of this study were to evaluate the effect
of glenoid component size and glenosphere type on impingement-free
range of movement (ROM) for extension and internal and external
rotation in a virtual RSA model, and to determine the optimal configuration
to reduce the incidence of friction-type scapular notching. Preoperative CT scans obtained in 21 patients (three male, 18
female) with primary osteoarthritis were analyzed using modelling
software. Two concurrent factors were tested for impingement-free
ROM and translation of the centre of rotation: glenosphere diameter
(36 mm Aims
Materials and Methods
Objectives. The objective of this study was to quantify the relative movement between the articular surfaces in the tibiotalar and subtalar joints during normal walking in asymptomatic individuals. Methods. 3D movement data of the ankle joint complex were acquired from 18 subjects using a biplanar fluoroscopic system and 3D-to-2D registration of bone models obtained from CT images. Surface relative velocity vectors (SRVVs) of the articular surfaces of the tibiotalar and subtalar joints were calculated. The relative movement of the articulating surfaces was quantified as the mean relative speed (RS) and synchronization index (SI. ENT. ) of the SRVVs. Results. SI. ENT. and mean RS data showed that the tibiotalar joint exhibited translational movement throughout the stance, with a mean SI. ENT. of 0.54 (. sd. 0.21). The mean RS of the tibiotalar joint during the 0% to 20% post heel-strike phase was 36.0 mm/s (. sd. 14.2), which was higher than for the rest of the stance period. The subtalar joint had a mean SI. ENT. value of 0.43 (. sd. 0.21) during the stance phase and exhibited a greater degree of
To validate the precision of digitally reconstructed radiograph (DRR) radiostereometric analysis (RSA) and the model-based method (MBM) RSA with respect to benchmark marker-based (MM) RSA for evaluation of kinematics in the native hip joint. Seven human cadaveric hemipelves were CT scanned and bone models were segmented. Tantalum beads were placed in the pelvis and proximal femoral bone. RSA recordings of the hips were performed during flexion, adduction and internal rotation. Stereoradiographic recordings were all analyzed with DRR, MBM and MM. Migration results for the MBM and DRR with respect to MM were compared. Precision was assessed as systematic bias (mean difference) and random variation (Pitman’s test for equal variance).Objectives
Methods
The objective of this study was to investigate bone healing after
internal fixation of displaced femoral neck fractures (FNFs) with
the Dynamic Locking Blade Plate (DLBP) in a young patient population
treated by various orthopaedic (trauma) surgeons. We present a multicentre prospective case series with a follow-up
of one year. All patients aged ≤ 60 years with a displaced FNF treated
with the DLBP between 1st August 2010 and December 2014 were included.
Patients with pathological fractures, concomitant fractures of the
lower limb, symptomatic arthritis, local infection or inflammation,
inadequate local tissue coverage, or any mental or neuromuscular
disorder were excluded. Primary outcome measure was failure in fracture
healing due to nonunion, avascular necrosis, or implant failure
requiring revision surgery.Aims
Patients and Methods
Computer hexapod assisted orthopaedic surgery (CHAOS), is a method
to achieve the intra-operative correction of long bone deformities
using a hexapod external fixator before definitive internal fixation
with minimally invasive stabilisation techniques. The aims of this study were to determine the reliability of this
method in a consecutive case series of patients undergoing femoral
deformity correction, with a minimum six-month follow-up, to assess
the complications and to define the ideal group of patients for
whom this treatment is appropriate. The medical records and radiographs of all patients who underwent
CHAOS for femoral deformity at our institution between 2005 and
2011 were retrospectively reviewed. Records were available for all
55 consecutive procedures undertaken in 49 patients with a mean
age of 35.6 years (10.9 to 75.3) at the time of surgery.Aims
Patients and Methods
The interaction between the lumbosacral spine
and the pelvis is dynamically related to positional change, and
may be complicated by co-existing pathology. This review summarises
the current literature examining the effect of sagittal spinal deformity
on pelvic and acetabular orientation during total hip arthroplasty
(THA) and provides recommendations to aid in placement of the acetabular
component for patients with co-existing spinal pathology or long
spinal fusions. Pre-operatively, patients can be divided into four
categories based on the flexibility and sagittal balance of the
spine. Using this information as a guide, placement of the acetabular
component can be optimal based on the type and significance of co-existing
spinal deformity. Cite this article:
The use of hinged implants in primary total knee
replacement (TKR) should be restricted to selected indications and mainly
for elderly patients. Potential indications for a rotating hinge
or pure hinge implant in primary TKR include: collateral ligament
insufficiency, severe varus or valgus deformity (>
20°) with necessary
relevant soft-tissue release, relevant bone loss including insertions
of collateral ligaments, gross flexion-extension gap imbalance,
ankylosis, or hyperlaxity. Although data reported in the literature
are inconsistent, clinical results depend on implant design, proper
technical use, and adequate indications. We present our experience
with a specific implant type that we have used for over 30 years
and which has given our elderly patients good mid-term results.
Because revision of implants with long cemented stems can be very
challenging, an effort should be made in the future to use shorter stems
in modular versions of hinged implants. Cite this article:
We determined the short-term clinical outcome
and migration within the bone of the humeral cementless component
of the Instrumented Bone Preserving (IBP) total elbow replacement
in a series of 16 patients. There were four men and 12 women with
a mean age at operation of 63 years (40 to 81). Migration was calculated
using radiostereometric analysis. There were no intra-operative
complications and no revisions. At two-year follow-up, all patients
showed a significant reduction in pain and functional improvement
of the elbow (both p <
0.001). Although ten components (63%)
showed movement or micromovement during the first six weeks, 14
(88%) were stable at one year post-operatively. Translation was
primarily found in the proximal direction (median 0.3 mm (interquartile range
(IQR) -0.09 to 0.8); the major
Mobile-bearing (MB) total knee replacement (TKR)
was introduced to reduce the risk of aseptic loosening and wear of
polyethylene inserts. However, no consistent clinical advantages
of mobile- over fixed-bearing (FB) TKR have been found. In this
study we evaluated whether mobile bearings have an advantage over
fixed bearings with regard to revision rates and clinical outcome
scores. Furthermore, we determined which modifying variables affected
the outcome. A systematic search of the literature was conducted to collect
clinical trials comparing MB and FB in primary TKR. The primary
outcomes were revision rates for any reason, aseptic loosening and
wear. Secondary outcomes included range of movement, Knee Society
score (KSS), Oxford knee score (OKS), Short-Form 12 (SF-12) score
and radiological parameters. Meta-regression techniques were used
to explore factors modifying the observed effect. Our search yielded 1827 publications, of which 41 studies met
our inclusion criteria, comprising over 6000 TKRs. Meta-analyses
showed no clinically relevant differences in terms of revision rates,
clinical outcome scores or patient-reported outcome measures between
MB and FB TKRs. It appears that theoretical assumptions of superiority
of MB over FB TKR are not borne out in clinical practice. Cite this article:
This prospective multicentre study was undertaken
to determine segmental movement, disc height and sagittal alignment
after total disc replacement (TDR) in the lumbosacral spine and
to assess the correlation of biomechanical properties to clinical
outcomes. A total of 173 patients with degenerative disc disease and low
back pain for more than one year were randomised to receive either
TDR or multidisciplinary rehabilitation (MDR). Segmental movement
in the sagittal plane and disc height were measured using distortion
compensated roentgen analysis (DCRA) comparing radiographs in active flexion
and extension. Correlation analysis between the range of movement
or disc height and patient-reported outcomes was performed in both
groups. After two years, no significant change in movement in the
sagittal plane was found in segments with TDR or between the two
treatment groups. It remained the same or increased slightly in
untreated segments in the TDR group and in this group there was
a significant increase in disc height in the operated segments.
There was no correlation between segmental movement or disc height
and patient-reported outcomes in either group. In this study, insertion of an intervertebral disc prosthesis
TDR did not increase movement in the sagittal plane and segmental
movement did not correlate with patient-reported outcomes. This
suggests that in the lumbar spine the movement preserving properties
of TDR are not major determinants of clinical outcomes. Cite this article:
The biomechanical function of the anteromedial
(AM) and posterolateral (PL) bundles of the anterior cruciate ligament
(ACL) remains controversial. Some studies report that the AM bundle
stabilises the knee joint in anteroposterior (AP) translation and
rotational movement (both internal and external) to the same extent
as the PL bundle. Others conclude that the PL bundle is more important
than the AM in controlling
Radiostereometric analysis (RSA) can detect early
micromovement in unstable implant designs which are likely subsequently
to have a high failure rate. In 2010, the Articular Surface Replacement
(ASR) was withdrawn because of a high failure rate. In 19 ASR femoral
components, the mean micromovement over the first two years after implantation
was 0.107 mm ( We conclude that the ASR femoral component achieves initial stability
and that early migration is not the mode of failure for this resurfacing
arthroplasty.
This study compared the outcome of total knee
replacement (TKR) in adult patients with fixed- and mobile-bearing prostheses
during the first post-operative year and at five years’ follow-up,
using gait parameters as a new objective measure. This double-blind
randomised controlled clinical trial included 55 patients with mobile-bearing (n
= 26) and fixed-bearing (n = 29) prostheses of the same design,
evaluated pre-operatively and post-operatively at six weeks, three
months, six months, one year and five years. Each participant undertook
two walking trials of 30 m and completed the EuroQol questionnaire,
Western Ontario and McMaster Universities osteoarthritis index,
Knee Society score, and visual analogue scales for pain and stiffness.
Gait analysis was performed using five miniature angular rate sensors
mounted on the trunk (sacrum), each thigh and calf. The study population
was divided into two groups according to age (≤ 70 years Improvements in most gait parameters at five years’ follow-up
were greater for fixed-bearing TKRs in older patients (>
70 years),
and greater for mobile-bearing TKRs in younger patients (≤ 70 years).
These findings should be confirmed by an extended age controlled
study, as the ideal choice of prosthesis might depend on the age
of the patient at the time of surgery.
Patients with skeletal dysplasia are prone to
developing advanced osteoarthritis of the knee requiring total knee replacement
(TKR) at a younger age than the general population. TKR in this
unique group of patients is a technically demanding procedure owing
to the deformity, flexion contracture, generalised hypotonia and ligamentous
laxity. We retrospectively reviewed the outcome of 11 TKRs performed
in eight patients with skeletal dysplasia at our institution using
the Stanmore Modular Individualised Lower Extremity System (SMILES)
custom-made rotating-hinge TKR. There were three men and five women
with mean age of 57 years (41 to 79). Patients were followed clinically
and radiologically for a mean of seven years (3 to 11.5). The mean
Knee Society clinical and function scores improved from 24 (14 to
36) and 20 (5 to 40) pre-operatively, respectively, to 68 (28 to
80) and 50 (22 to 74), respectively, at final follow-up. Four complications
were recorded, including a patellar fracture following a fall, a
tibial peri-prosthetic fracture, persistent anterior knee pain,
and aseptic loosening of a femoral component requiring revision.
Our results demonstrate that custom primary rotating-hinge TKR in
patients with skeletal dysplasia is effective at relieving pain,
with a satisfactory range of movement and improved function. It compensates
for bony deformity and ligament deficiency and reduces the likelihood
of corrective osteotomy. Patellofemoral joint complications are
frequent and functional outcome is worse than with primary TKR in
the general population.
