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 August 2015 Hip &
Pelvis Roundup360 looks at: The well-fixed acetabular revision; Predicting complications in revision arthroplasty; Is infection associated with fixation?; Front or back? An enduring question in hip surgery; Muscle-sparing approaches?; Gabapentin as a post-operative analgesic adjunct; An Indian take on AVN of the hip; Weight loss and arthroplasty
If patients could recall their physical status
before total hip (THA) or knee arthroplasty (TKA) accurately it
could have valuable applications both clinically and for research.
This study evaluated the accuracy of a patient’s recollection one
year after either THA or TKA using the Oxford hip or knee scores
(OHS and OKS). In total, 113 patients (59 THA, 54 TKA) who had completed
the appropriate score pre-operatively were asked to complete the
score again at a mean of 12.4 months (standard deviation ( While there were no significant differences between the actual
and recalled pre-operative scores (OHS mean difference 0.8, A patient’s recollection of pre-operative pain and function is
inaccurate one year after THA or TKA. Cite this article:
The purpose of this paper is to discuss the risk
factors, prevention strategies, classification, and treatment of
intra-operative femur fractures sustained during primary and revision
total hip arthroplasty.
Oxidised zirconium (OxZi) has been developed
as an alternative bearing surface for femoral heads in total hip arthroplasty
(THA). This study has investigated polyethylene wear, functional
outcomes and complications, comparing OxZi and cobalt–chrome (CoCr)
as part of a three-arm, multicentre randomised controlled trial.
Patients undergoing THA from four institutions were prospectively
randomised into three groups. Group A received a CoCr femoral head
and highly cross-linked polyethylene (XLPE) liner; Group B received
an OxZi femoral head and XLPE liner; Group C received an OxZi femoral
head and ultra-high molecular weight polyethylene (UHMWPE) liner.
At five years, 368 patients had no statistically significant differences
in short-form-36 (p = 0.176 mental, p = 0.756 physical), Western
Ontario and McMaster Universities Osteoarthritis Index (p = 0.847),
pain scores
(p = 0.458) or complications. The mean rate of linear wear was 0.028
mm/year (standard deviation ( Cite this article:
There is no single standardised method of measuring
the orientation of the acetabular component on plain radiographs
after total hip arthroplasty. We assessed the reliability and accuracy
of three methods of assessing anteversion of the acetabular component
for 551 THAs using the PolyWare software and the methods of Liaw
et al, and of Woo and Morrey. All measurements of the three methods
had excellent intra- and inter-observer reliability. The values
of the PolyWare software, which determines version of the acetabular
component by edge detection were regarded as the reference standard.
Although the PolyWare software and the method of Liaw et al were similarly
precise, the method of Woo and Morrey was significantly less accurate
(p <
0.001). The method of Liaw et al seemed to be more accurate
than that of Woo and Morrey when compared with the measurements
using the PolyWare software. If the qualified lateral radiograph
was selected, anteversion measured using the method of Woo and Morrey
was considered to be relatively reliable. Cite this article:
We evaluated the accuracy with which a custom-made
acetabular component could be positioned at revision arthroplasty
of the hip in patients with a Paprosky type 3 acetabular defect. A total of 16 patients with a Paprosky type 3 defect underwent
revision surgery using a custom-made trabecular titanium implant.
There were four men and 12 women with a median age of 67 years (48
to 79). The planned inclination (INCL), anteversion (AV), rotation
and centre of rotation (COR) of the implant were compared with the post-operative
position using CT scans. A total of seven implants were malpositioned in one or more parameters:
one with respect to INCL, three with respect to AV, four with respect
to rotation and five with respect to the COR. To the best of our knowledge, this is the first study in which
CT data acquired for the pre-operative planning of a custom-made
revision acetabular implant have been compared with CT data on the
post-operative position. The results are encouraging. Cite this article:
In this study we evaluated whether pre-operative
Western Ontario and McMaster Universities (WOMAC) osteoarthritis
scores can predict satisfaction following total hip arthroplasty
(THA). Prospective data for a cohort of patients undergoing THA
from two large academic centres were collected, and pre-operative
and one-year post-operative WOMAC scores and a 25-point satisfaction
questionnaire were obtained for 446 patients. Satisfaction scores
were dichotomised into either improvement or deterioration. Scatter
plots and Spearman’s rank correlation coefficient were used to describe
the association between pre-operative WOMAC and one-year post-operative WOMAC
scores and patient satisfaction. Satisfaction was compared using
receiver operating characteristic (ROC) analysis against pre-operative,
post-operative and δ WOMAC scores. We found no relationship between pre-operative WOMAC scores and
one-year post-operative WOMAC or satisfaction scores, with Spearman’s
rank correlation coefficients of 0.16 and –0.05, respectively. The
ROC analysis showed areas under the curve (AUC) of 0.54 (pre-operative
WOMAC), 0.67 (post-operative WOMAC) and 0.43 (δ WOMAC), respectively,
for an improvement in satisfaction. We conclude that the pre-operative WOMAC score does not predict
the post-operative WOMAC score or patient satisfaction after THA,
and that WOMAC scores can therefore not be used to prioritise patient
care. Cite this article:
Between January 2000 and December 2007, 31 patients 90 years of age or older underwent total hip replacement at our hospital. Their data were collected prospectively. The rate of major medical complications was 9%. The surgical re-operation rate was 3%. The requirement for blood transfusion was 71% which was much higher than for younger patients. The 30-day, one-year and current mortality figures were 6.4% (2 of 31), 9.6% (3 of 31) and 55% (17 of 31), respectively, with a mean follow-up for the 14 surviving patients of six years. Cox’s regression analysis revealed no significant independent predictors of mortality. Only 52% of patients returned immediately to their normal abode, with 45% requiring a prolonged period of rehabilitation. This is the first series to assess survival five years after total hip replacement for patients in their 90th year and beyond. Hip replacement in the extreme elderly should not be discounted on the grounds of age alone, although the complication rate exceeds that for younger patients. It can be anticipated that almost half of the patients will survive five years after surgery.
We report the kinematic and early clinical results
of a patient- and observer-blinded randomised controlled trial in which
CT scans were used to compare potential impingement-free range of
movement (ROM) and acetabular component cover between patients treated
with either the navigated ‘femur-first’ total hip arthroplasty (THA) method
(n = 66; male/female 29/37, mean age 62.5 years; 50 to 74) or conventional
THA (n = 69; male/female 35/34, mean age 62.9 years; 50 to 75).
The Hip Osteoarthritis Outcome Score, the Harris hip score, the
Euro-Qol-5D and the Mancuso THA patient expectations score were
assessed at six weeks, six months and one year after surgery. A
total of 48 of the patients (84%) in the navigated ‘femur-first’
group and 43 (65%) in the conventional group reached all the desirable
potential ROM boundaries without prosthetic impingement for activities
of daily living (ADL) in flexion, extension, abduction, adduction
and rotation (p = 0.016). Acetabular component cover and surface
contact with the host bone were >
87% in both groups. There was
a significant difference between the navigated and the conventional
groups’ Harris hip scores six weeks after surgery (p = 0.010). There
were no significant differences with respect to any clinical outcome
at six months and one year of follow-up. The navigated ‘femur-first’
technique improves the potential ROM for ADL without prosthetic
impingement, although there was no observed clinical difference
between the two treatment groups. Cite this article:
We hypothesised that the use of tantalum (Ta)
acetabular components in revision total hip arthroplasty (THA) was protective
against subsequent failure due to infection. We identified 966 patients
(421 men, 545 women and 990 hips) who had undergone revision THA
between 2000 and 2013. The mean follow up was 40.2 months (3 months
to 13.1 years). The mean age of the men and women was 62.3 years
(31 to 90) and 65.1 years (25 to 92), respectively. Titanium (Ti) acetabular components were used in 536 hips while
Ta components were used in 454 hips. In total, 73 (7.3%) hips experienced
subsequent acetabular failure. The incidence of failure was lower
in the Ta group at 4.4% (20/454) compared with 9.9% (53/536) in
the Ti group (p <
0.001, odds ratio 2.38; 95% CI 1.37 to 4.27).
Among the 144 hips (64 Ta, 80 Ti) for which revision had been performed
because of infection, failure due to a subsequent infection was
lower in the Ta group at 3.1% (2/64) compared with 17.5% (14/80)
for the Ti group (p = 0.006). Thus, the use of Ta acetabular components during revision THA
was associated with a lower incidence of failure from all causes
and Ta components were associated with a lower incidence of subsequent
infection when used in patients with periprosthetic joint infection. 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:
Metal-on-metal resurfacing of the hip (MoMHR)
has enjoyed a resurgence in the last decade, but is now again in question
as a routine option for osteoarthritis of the hip. Proponents of
hip resurfacing suggest that its survival is superior to that of
conventional hip replacement (THR), and that hip resurfacing is
less invasive, is easier to revise than THR, and provides superior
functional outcomes. Our argument serves to illustrate that none
of these proposed advantages have been realised and new and unanticipated
serious complications, such as pseudotumors, have been associated
with the procedure. As such, we feel that the routine use of MoMHR
is not justified. Cite this article:
We report the clinical and radiographic outcomes
of 208 consecutive femoral revision arthroplasties performed in 202
patients (119 women, 83 men) between March 1991 and December 2007
using the X-change Femoral Revision System, fresh-frozen morcellised
allograft and a cemented polished Exeter stem. All patients were
followed prospectively. The mean age of the patients at revision
was 65 years (30 to 86). At final review in December 2013 a total
of 130 patients with 135 reconstructions (64.9%) were alive and
had a non re-revised femoral component after a mean follow-up of
10.6 years (4.7 to 20.9). One patient was lost to follow-up at six
years, and their data were included up to this point.
Re-operation for any reason was performed in 33 hips (15.9%), in
13 of which the femoral component was re-revised (6.3%). The mean
pre-operative Harris hip score was 52 (19 to 95) (n = 73) and improved
to 80 (22 to 100) (n = 161) by the last follow-up. Kaplan–Meier
survival with femoral re-revision for any reason as the endpoint
was 94.9% (95% confidence intervals (CI) 90.2 to 97.4) at ten years;
with femoral re-revision for aseptic loosening as the endpoint it was
99.4% (95% CI 95.7 to 99.9); with femoral re-operation for any reason
as the endpoint it was 84.5% (95% CI 78.3 to 89.1); and with subsidence ≥ 5
mm it was 87.3% (95% CI 80.5 to 91.8). Femoral revision with the
use of impaction allograft bone grafting and a cemented polished
stem results in a satisfying survival rate at a mean of ten years’ follow-up. Cite this article:
Conventional cemented acetabular components are
reported to have a high rate of failure when implanted into previously
irradiated bone. We recommend the use of a cemented reconstruction
with the addition of an acetabular reinforcement cross to improve
fixation. We reviewed a cohort of 45 patients (49 hips) who had undergone
irradiation of the pelvis and a cemented total hip arthroplasty
(THA) with an acetabular reinforcement cross. All hips had received
a minimum dose of 30 Gray (Gy) to treat a primary nearby tumour
or metastasis. The median dose of radiation was 50 Gy (Q1 to Q3:
45 to 60; mean: 49.57, 32 to 72). The mean follow-up after THA was 51 months (17 to 137). The cumulative
probability of revision of the acetabular component for a mechanical
reason was 0% (0 to 0%) at 24 months, 2.9% (0.2 to 13.3%) at 60
months and 2.9% (0.2% to 13.3%) at 120 months, respectively. One
hip was revised for mechanical failure and three for infection. Cemented acetabular components with a reinforcement cross provide
good medium-term fixation after pelvic irradiation. These patients
are at a higher risk of developing infection of their THA. Cite this article:
Large femoral heads have been used with increasing
frequency over the last decade. The prime reason is likely the effect
of large heads on stability. The larger head neck ratio, combined
with the increased jump distance of larger heads result in a greater
arc of impingement free motion, and greater resistance to dislocation
in a provocative position. Multiple studies have demonstrated clear
clinical efficacy in diminishing dislocation rates with the use
of large femoral heads. With crosslinked polyethylene, wear has
been shown to be equivalent between larger and smaller heads. However,
the stability advantages of increasing diameter beyond 38 mm have
not been clearly demonstrated. More importantly, recent data implicates
large heads in the increasing prevalence of groin pain and psoas impingement.
There are clear benefits with larger femoral head diameters, but
the advantages of diameters beyond 38 mm have not yet been demonstrated
clinically.
In 2005, we demonstrated that the polished triple-tapered
C-stem at two years had migrated distally and rotated internally.
From that series, 33 patients have now been followed radiologically,
clinically and by radiostereometric analysis (RSA) for up to ten
years. The distal migration within the cement mantle had continued
and reached a mean of 2 mm (0.5 to 4.0) at ten years. Internal rotation,
also within the cement mantle, was a mean 3.8° (external 1.6° to
internal 6.6°) The cement mantle did not show any sign of migration
or loosening in relation to the femoral bone. There were no clinical
or radiological signs indicating that the migration or rotation
within the cement mantle had had any adverse effects for the patients. Cite this article:
Substantial healthcare resources have been devoted
to computer navigation and patient-specific instrumentation systems
that improve the reproducibility with which neutral mechanical alignment
can be achieved following total knee replacement (TKR). This choice of
alignment is based on the long-held tenet that the alignment of
the limb post-operatively should be within 3° of a neutral mechanical
axis. Several recent studies have demonstrated no significant difference
in survivorship when comparing well aligned Review of the literature suggests that a neutral mechanical axis
remains the optimal guide to alignment. Cite this article:
