Femoral stem version has a major influence on
impingement and early post-operative stability after total hip arthroplasty
(THA). The main objective of this study was to evaluate the validity
of a novel radiological method for measuring stem version. Anteroposterior
(AP) radiographs and three-dimensional CT scans were obtained for
115 patients (female/male 63/72, mean age 62.5 years (50 to 75))
who had undergone minimally invasive, cementless THA. Stem version was
calculated from the AP hip radiograph by rotation-based change in
the projected prosthetic neck–shaft (NSA*) angle using the mathematical
formula ST = arcos [tan (NSA*) / tan (135)]. We used two independent
observers who repeated the analysis after a six-week interval. Radiological
measurements were compared with 3D-CT measurements by an independent,
blinded external institute. We found a mean difference of 1.2° ( We found that femoral tilt was associated with the mean radiological
measurement error (r = 0.22, p = 0.02). The projected neck–shaft angle is a reliable method for measuring
stem version on AP radiographs of the hip after a THA. However,
a highly standardised radiological technique is required for its
precise measurement. Cite this article:
We aimed to further evaluate the biomechanical characteristics
of two locking screws Synthetic tubular bone models representing normal bone density
and osteoporotic bone density were used. Artificial fracture gaps
of 1 cm were created in each specimen before fixation with one of
two constructs: 1) two locking screws using a five-hole locking
compression plate (LCP) plate; or 2) three non-locking screws with
a seven-hole LCP plate across each side of the fracture gap. The
stiffness, maximum displacement, mode of failure and number of cycles
to failure were recorded under progressive cyclic torsional and
eccentric axial loading.Objectives
Methods
Down’s syndrome is associated with a number of
musculoskeletal abnormalities, some of which predispose patients
to early symptomatic arthritis of the hip. The purpose of the present
study was to review the general and hip-specific factors potentially
compromising total hip replacement (THR) in patients with Down’s
syndrome, as well as to summarise both the surgical techniques that
may anticipate the potential adverse impact of these factors and
the clinical results reported to date. A search of the literature
was performed, and the findings further informed by the authors’
clinical experience, as well as that of the hip replacement in Down
Syndrome study group. The general factors identified include a high
incidence of ligamentous laxity, as well as associated muscle hypotonia
and gait abnormalities. Hip-specific factors include: a high incidence
of hip dysplasia, as well as a number of other acetabular, femoral
and combined femoroacetabular anatomical variations. Four studies
encompassing 42 hips, which reported the clinical outcomes of THR
in patients with Down’s syndrome, were identified. All patients
were successfully treated with standard acetabular and femoral components.
The use of supplementary acetabular screw fixation to enhance component
stability was frequently reported. The use of constrained liners
to treat intra-operative instability occurred in eight hips. Survival
rates of between 81% and 100% at a mean follow-up of 105 months
(6 to 292) are encouraging. Overall, while THR in patients with
Down’s syndrome does present some unique challenges, the overall
clinical results are good, providing these patients with reliable
pain relief and good function. Cite this article:
The aim of this study was to compare the operating
time, length of stay (LOS), adverse events and rate of re-admission
for elderly patients with a fracture of the hip treated using either
general or spinal anaesthesia. Patients aged ≥ 70 years who underwent
surgery for a fracture of the hip between 2010 and 2012 were identified
from the American College of Surgeons National Surgical Quality
Improvement Program (ACS-NSQIP) database. Of the 9842 patients who
met the inclusion criteria, 7253 (73.7%) were treated with general
anaesthesia and 2589 (26.3%) with spinal anaesthesia. On propensity-adjusted
multivariate analysis, general anaesthesia was associated with slightly increased
operating time (+5 minutes, 95% confidence interval (CI) +4 to +6,
p <
0.001) and post-operative time in the operating room (+5
minutes, 95% CI +2 to +8, p <
0.001) compared with spinal anaesthesia.
General anaesthesia was associated with a shorter LOS (hazard ratio
(HR) 1.28, 95% CI 1.22 to 1.34, p <
0.001). Any adverse event
(odds ratio (OR) 1.21, 95% CI 1.10 to 1.32, p <
0.001), thromboembolic
events (OR 1.90, 95% CI 1.24 to 2.89, p = 0.003), any minor adverse
event (OR 1.19, 95% CI 1.09 to 1.32, p <
0.001), and blood transfusion
(OR 1.34, 95% CI 1.22 to 1.49, p <
0.001) were associated with
general anaesthesia. General anaesthesia was associated with decreased
rates of urinary tract infection (OR 0.73, 95% CI 0.62 to 0.87,
p <
0.001). There was no clear overall advantage of one type
of anaesthesia over the other, and surgeons should be aware of the
specific risks and benefits associated with each type. Cite this article:
We retrospectively reviewed the records of 1150
computer-assisted total knee replacements and analysed the clinical
and radiological outcomes of 45 knees that had arthritis with a
pre-operative recurvatum deformity. The mean pre-operative hyperextension
deformity of 11° (6° to 15°), as measured by navigation at the start
of the operation, improved to a mean flexion deformity of 3.1° (0°
to 7°) post-operatively. A total of 41 knees (91%) were managed
using inserts ≤ 12.5 mm thick, and none had mediolateral laxity
>
2 mm from a mechanical axis of 0° at the end of the surgery. At
a mean follow-up of 26.4 months (13 to 48) there was significant
improvement in the mean Knee Society, Oxford knee and Western Ontario
and McMaster Universities Osteoarthritis Index scores compared with
the pre-operative values. The mean knee flexion improved from 105°
(80° to 125°) pre-operatively to 131° (120° to 145°), and none of
the limbs had recurrent recurvatum. These early results show that total knee replacement using computer
navigation and an algorithmic approach for arthritic knees with
a recurvatum deformity can give excellent radiological and functional
outcomes without recurrent deformity.
We performed a retrospective review of a consecutive
series of 178 Mobility total ankle replacements (TARs) performed
by three surgeons between January 2004 and June 2009, and analysed
radiological parameters and clinical outcomes in a subgroup of 129
patients. The mean follow-up was 4 years (2 to 6.3). A total of
ten revision procedures (5.6%) were undertaken. The mean Ankle Osteoarthritis
Scale (AOS) pain score was 17 (0 to 88) and 86% of patients were
clinically improved at follow-up. However, 18 patients (18 TARs,
14%) had a poor outcome with an AOS pain score of >
30. A worse
outcome was associated with a pre-operative diagnosis of post-traumatic degenerative
arthritis. However, no pre- or post-operative radiological parameters
were significantly associated with a poor outcome. Of the patients
with persistent pain, eight had predominantly medial-sided pain.
Thirty TARs (29%) had a radiolucency in at least one zone. The outcome of the Mobility TAR at a mean of four years is satisfactory
in >
85% of patients. However, there is a significant incidence
of persistent pain, particularly on the medial side, for which we
were unable to establish a cause. Cite this article:
In this prospective study we studied the effect
of the inclination angle of the acetabular component on polyethylene wear
and component migration in cemented acetabular sockets using radiostereometric
analysis. A total of 120 patients received either a cemented Reflection
All-Poly ultra-high-molecular-weight polyethylene or a cemented
Reflection All-Poly highly cross-linked polyethylene acetabular
component, combined with either cobalt–chrome or Oxinium femoral
heads. Femoral head penetration and migration of the acetabular
component were assessed with repeated radiostereometric analysis
for two years. The inclination angle was measured on a standard
post-operative anteroposterior pelvic radiograph. Linear regression
analysis was used to determine the relationship between the inclination
angle and femoral head penetration and migration of the acetabular component. We found no relationship between the inclination angle and penetration
of the femoral head at two years’ follow-up (p = 0.9). Similarly,
our data failed to reveal any statistically significant correlation
between inclination angle and migration of these cemented acetabular
components (p = 0.07 to p = 0.9).
Stems may improve fixation and stability of components
during revision total knee replacement. However, the choice between
cemented and cementless stems is not a clear one. Cemented stems
offer several advantages in terms of versatility, mechanical stability, surgical
technique and clinical outcome over their cementless counterpart. Cite this article:
We evaluated an operative technique, described
by the Exeter Hip Unit, to assist accurate introduction of the femoral
component. We assessed whether it led to a reduction in the rate
of leg-length discrepancy after total hip arthroplasty (THA). A total of 100 patients undergoing THA were studied retrospectively;
50 were undertaken using the test method and 50 using conventional
methods as a control group. The groups were matched with respect
to patient demographics and the grade of surgeon. Three observers
measured the depth of placement of the femoral component on post-operative
radiographs and measured the length of the legs. There was a strong correlation between the depth of insertion
of the femoral component and the templated depth in the test group
(R = 0.92), suggesting accuracy of the technique. The mean leg-length
discrepancy was 5.1 mm (0.6 to 21.4) pre-operatively and 1.3 mm
(0.2 to 9.3) post-operatively. There was no difference between Consultants
and Registrars as primary surgeons. Agreement between the templated
and post-operative depth of insertion was associated with reduced
post-operative leg-length discrepancy. The intra-class coefficient
was R ≥ 0.88 for all measurements, indicating high observer agreement.
The post-operative leg-length discrepancy was significantly lower
in the test group (1.3 mm) compared with the control group (6.3
mm, p <
0.001). The Exeter technique is reproducible and leads to a lower incidence
of leg-length discrepancy after THA. Cite this article:
The purpose of this study was to investigate whether the femoral
head–neck contour, characterised by the alpha angle, varies with
the stage of physeal maturation using MRI evaluation of an asymptomatic
paediatric population. Paediatric volunteers with asymptomatic hips were recruited to
undergo MRI of both hips. Femoral head physes were graded from 1
(completely open) to 6 (completely fused). The femoral head–neck
contour was evaluated using the alpha angle, measured at the 3:00
(anterior) and 1:30 (anterosuperior) positions and correlated with
physeal grade, with gender sub-analysis performed.Objectives
Methods
The December 2014 Hip &
Pelvis Roundup360 looks at: Sports and total hips; topical tranexamic acid and blood conservation in hip replacement; blind spots and biases in hip research; no recurrence in cam lesions at two years; to drain or not to drain?; sonication and diagnosis of implant associated infection; and biomarkers and periprosthetic infection
We evaluated all cases involving the combined use of a subtrochanteric derotational femoral shortening osteotomy with a cemented Exeter stem performed at our institution. With severe developmental dysplasia of the hip an osteotomy is often necessary to achieve shortening and derotation of the proximal femur. Reduction can be maintained with a 3.5 mm compression plate while the implant is cemented into place. Such a plate was used to stabilise the osteotomy in all cases. Intramedullary autograft helps to prevent cement interposition at the osteotomy site and promotes healing. There were 15 female patients (18 hips) with a mean age of 51 years (33 to 75) who had a Crowe IV dysplasia of the hip and were followed up for a mean of 114 months (52 to 168). None was lost to follow-up. All clinical scores were collected prospectively. The Charnley modification of the Merle D’Aubigné-Postel scores for pain, function and range of movement showed a statistically significant improvement from a mean of 2.4 (1 to 4), 2.3 (1 to 4), 3.4 (1 to 6) to 5.2 (3 to 6), 4.4 (3 to 6), 5.2 (4 to 6), respectively. Three acetabular revisions were required for aseptic loosening; one required femoral revision for access. One osteotomy failed to unite at 14 months and was revised successfully. No other case required a femoral revision. No postoperative sciatic nerve palsy was observed. Cemented Exeter femoral components perform well in the treatment of Crowe IV dysplasia with this procedure.
Filling the empty holes in peri-articular locking
plates may improve the fatigue strength of the fixation. The purpose of
this A locking/compression plate was applied to 33 synthetic femurs
and then a 6 cm metaphyseal defect was created (AO Type 33-A3).
The specimens were then divided into three groups: unplugged, plugged
with locking screw only and fully plugged holes. They were then
tested using a stepwise or run-out fatigue protocol, each applying
cyclic physiological multiaxial loads. All specimens in the stepwise group failed at the 770 N load
level. The mean number of cycles to failure for the stepwise specimen
was 25 500 cycles ( In conclusion, filling the empty combination locking/compression
holes in peri-articular distal femur locking plates at the level
of supracondylar comminution does not increase the fatigue life
of the fixation in a comminuted supracondylar femoral fracture model
(AO 33-A3) with a 6 cm gap.
This review examines the future of total hip arthroplasty, aiming to avoid past mistakes
The October 2014 Spine Roundup360 looks at: microdiscectomy is not exactly a hands-down winner; lumbar spinal stenosis unpicked; Wallis implant helpful in lumbosacral decompression; multidisciplinary rehabilitation is good for back pain; and understanding the sciatic stretch test.
There are significant differences in the methods and styles of orthopaedic surgical training between continents, all with the aim to produce competent consultant surgeons, but the differences in training content and pathway are vast. We review and contrast the key differences between three continents.
In this prospective study a total of 80 consecutive
Chinese patients with Crowe type I or II developmental dysplasia of
the hip were randomly assigned for hip resurfacing arthroplasty
(HRA) or total hip replacement (THR). Three patients assigned to HRA were converted to THR, and three
HRA patients and two THR patients were lost to follow-up. This left
a total of 34 patients (37 hips) who underwent HRA and 38 (39 hips)
who underwent THR. The mean follow-up was 59.4 months (52 to 70)
in the HRA group and 60.6 months (50 to 72) in the THR group. There was
no failure of the prosthesis in either group. Flexion of the hip
was significantly better after HRA, but there was no difference
in the mean post-operative Harris hip scores between the groups.
The mean size of the acetabular component in the HRA group was significantly
larger than in the THR group (49.5 mm vs 46.1 mm, p = 0.001). There was
no difference in the mean abduction angle of the acetabular component
between the two groups. Although the patients in this series had risk factors for failure
after HRA, such as low body weight, small femoral heads and dysplasia,
the clinical results of resurfacing in those with Crowe type I or
II hip dysplasia were satisfactory. Patients in the HRA group had
a better range of movement, although neck-cup impingement was observed.
However, more acetabular bone was sacrificed in HRA patients, and
it is unclear whether this will have an adverse effect in the long
term.
The amount of anteroposterior laxity required for a good range of movement and knee function in a cruciate-retaining total knee replacement (TKR) continues to be debated. We undertook a retrospective study to evaluate the effects of anteroposterior laxity on the range of movement and knee function in 55 patients following the e-motion cruciate-retaining TKR with a minimum follow-up of two years. The knees were divided into stable (anteroposterior translation, ≤ 10 mm, 38 patients) and unstable (anteroposterior translation, >
10 mm, 17) groups based on the anteroposterior laxity, measured using stress radiographs. We compared the Hospital for Special Surgery (HSS) scores, the Western Ontario MacMasters University Osteoarthritis (WOMAC) index, weight-bearing flexion, non-weight-bearing flexion and the reduction of flexion under weight-bearing There were no differences between the stable and unstable groups with regard to the mean HHS and WOMAC total scores, as well as weight-bearing and non-weight-bearing flexion (p = 0.277, p = 0.082, p = 0.095 and p = 0.646, respectively). However, the stable group had a better WOMAC function score and less delta flexion than the unstable group (p = 0.011 and p = 0.005, respectively). Our results suggest that stable knees with laxity ≤ 10 mm have a good functional outcome and less reduction of flexion under weight-bearing conditions than unstable knees with laxity >
10 mm following an e-motion cruciate-retaining TKR.
A national, multi-centre study was designed in
which a questionnaire quantifying the degree of patient satisfaction
and residual symptoms in patients following total knee replacement
(TKR) was administered by an independent, blinded third party survey
centre. A total of 90% of patients reported satisfaction with the
overall functioning of their knee, but 66% felt their knee to be
‘normal’, with the reported incidence of residual symptoms and functional
problems ranging from 33% to 54%. Female patients and patients from
low-income households had increased odds of reporting dissatisfaction.
Neither the use of contemporary implant designs (gender-specific,
high-flex, rotating platform) or custom cutting guides (CCG) with
a neutral mechanical axis target improved patient-perceived outcomes.
However, use of a CCG to perform a so-called kinematically aligned
TKR showed a trend towards more patients reporting their knee to
feel ‘normal’ when compared with a so called mechanically aligned
TKR This data shows a degree of dissatisfaction and residual symptoms
following TKR, and that several recent modifications in implant
design and surgical technique have not improved the current situation. Cite this article:
We are currently facing an epidemic of periprosthetic
fractures around the hip. They may occur either during surgery or
post-operatively. Although the acetabulum may be involved, the femur
is most commonly affected. We are being presented with new, difficult
fracture patterns around cemented and cementless implants, and we
face the challenge of an elderly population who may have grossly
deficient bone and may struggle to rehabilitate after such injuries.
The correct surgical management of these fractures is challenging.
This article will review the current choices of implants and techniques
available to deal with periprosthetic fractures of the femur. Cite this article: