Lumbar fusion is known to reduce the variation in pelvic tilt
between standing and sitting. A flexible lumbo-pelvic unit increases
the stability of total hip arthroplasty (THA) when seated by increasing
anterior clearance and acetabular anteversion, thereby preventing
impingement of the prosthesis. Lumbar fusion may eliminate this protective
pelvic movement. The effect of lumbar fusion on the stability of
total hip arthroplasty has not previously been investigated. The Medicare database was searched for patients who had undergone
THA and spinal fusion between 2005 and 2012. PearlDiver software
was used to query the database by the International Classification
of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) procedural
code for primary THA and lumbar spinal fusion. Patients who had
undergone both lumbar fusion and THA were then divided into three
groups: 1 to 2 levels, 3 to 7 levels and 8+ levels of fusion. The
rate of dislocation in each group was established using ICD-9-CM codes.
Patients who underwent THA without spinal fusion were used as a
control group. Statistical significant difference between groups
was tested using the chi-squared test, and significance set at p
<
0.05.Aims
Patients and Methods
Accurate placement of the acetabular component is essential in
total hip arthroplasty (THA). The purpose of this study was to determine
if the ability to achieve inclination of the acetabular component
within the ‘safe-zone’ of 30° to 50° could be improved with the
use of an inclinometer. We reviewed 167 primary THAs performed by a single surgeon over
a period of 14 months. Procedures were performed at two institutions:
an inpatient hospital, where an inclinometer was used (inclinometer
group); and an ambulatory centre, where an inclinometer was not
used as it could not be adequately sterilized (control group). We excluded
47 patients with a body mass index (BMI) of > 40 kg/m2,
age of > 68 years, or a surgical indication other than osteoarthritis
whose treatment could not be undertaken in the ambulatory centre.
There were thus 120 patients in the study, 68 in the inclinometer
group and 52 in the control group. The inclination angles of the acetabular
component were measured from de-identified plain radiographs by
two blinded investigators who were not involved in the surgery.
The effect of the use of the inclinometer on the inclination angle
was determined using multivariate regression analysis.Aims
Patients and Methods
We previously reported the long-term results of the cementless Duraloc-Profile total hip arthroplasty (THA) system in a 12- to 15-year follow-up study. In this paper, we provide an update on the clinical and radiological results of a previously reported cohort of patients at 23 to 26 years´ follow-up. Of the 99 original patients (111 hips), 73 patients (82 hips) with a mean age of 56.8 years (21 to 70) were available for clinical and radiological study at a minimum follow-up of 23 years. There were 40 female patients (44 hips) and 33 male patients (38 hips).Aims
Patients and Methods
The purpose of this study was to examine whether leg-length discrepancy (LLD) following unilateral total hip arthroplasty (THA) affects the incidence of contralateral head collapse and subsequent THA in patients with bilateral osteonecrosis, and to determine factors associated with subsequent collapse. We identified 121 patients with bilateral non-traumatic osteonecrosis who underwent THA between 2003 and 2011 to treat a symptomatic hip, and who also exhibited medium-to-large lesions (necrotic area ≥ 30%) in an otherwise asymptomatic non-operated hip. Of the 121 patients, 71 were male (59%) and 50 were female (41%), with a mean age of 51 years (19 to 71) at the time of initial THA. All patients were followed for at least five years and were assessed according to the presence of a LLD (non-LLD Aims
Patients and Methods
The best method of treating unstable pelvic fractures that involve
the obturator ring is still a matter for debate. This study compared
three methods of treatment: nonoperative, isolated posterior fixation
and combined anteroposterior stabilization. The study used data from the German Pelvic Trauma Registry and
compared patients undergoing conservative management (n = 2394),
surgical treatment (n = 1345) and transpubic surgery, including
posterior stabilization (n = 730) with isolated posterior osteosynthesis
(n = 405) in non-complex Type B and C fractures that only involved the
obturator ring anteriorly. Calculated odds ratios were adjusted
for potential confounders. Outcome criteria were intraoperative
and general short-term complications, the incidence of nerve injuries,
and mortality.Aims
Patients and Methods
The aims of this study were to examine the rate at which the
positioning of the acetabular component, leg length discrepancy
and femoral offset are outside an acceptable range in total hip
arthroplasties (THAs) which either do or do not involve the use
of intra-operative digital imaging. A retrospective case-control study was undertaken with 50 patients
before and 50 patients after the integration of an intra-operative
digital imaging system in THA. The demographics of the two groups
were comparable for body mass index, age, laterality and the indication
for surgery. The digital imaging group had more men than the group without.
Surgical data and radiographic parameters, including the inclination
and anteversion of the acetabular component, leg length discrepancy,
and the difference in femoral offset compared with the contralateral
hip were collected and compared, as well as the incidence of altering
the position of a component based on the intra-operative image.Aims
Patients and Methods
The objective of this study was to assess the association between whole body sagittal balance and risk of falls in elderly patients who have sought treatment for back pain. Balanced spinal sagittal alignment is known to be important for the prevention of falls. However, spinal sagittal imbalance can be markedly compensated by the lower extremities, and whole body sagittal balance including the lower extremities should be assessed to evaluate actual imbalances related to falls. Patients over 70 years old who visited an outpatient clinic for back pain treatment and underwent a standing whole-body radiograph were enrolled. Falls were prospectively assessed for 12 months using a monthly fall diary, and patients were divided into fallers and non-fallers according to the history of falls. Radiological parameters from whole-body radiographs and clinical data were compared between the two groups.Objectives
Methods
Normal sagittal spine-pelvis-lower extremity alignment is crucial in humans for maintaining an ergonomic upright standing posture, and pathogenesis in any segment leads to poor balance. The present study aimed to investigate how this sagittal alignment can be affected by severe knee osteoarthritis (KOA), and whether associated changes corresponded with symptoms of lower back pain (LBP) in this patient population. Lateral radiograph films in an upright standing position were obtained from 59 patients with severe KOA and 58 asymptomatic controls free from KOA. Sagittal alignment of the spine, pelvis, hip and proximal femur was quantified by measuring several radiographic parameters. Global balance was accessed according to the relative position of the C7 plumb line to the sacrum and femoral heads. The presence of chronic LBP was documented. Comparisons between the two groups were carried by independent samples Objectives
Methods
Sagittal alignment of the lumbosacral spine, and specifically pelvic incidence (PI), has been implicated in the development of spine pathology, but generally ignored with regards to diseases of the hip. We aimed to determine if increased PI is correlated with higher rates of hip osteoarthritis (HOA). The effect of PI on the development of knee osteoarthritis (KOA) was used as a negative control. We studied 400 well-preserved cadaveric skeletons ranging from 50 to 79 years of age at death. Each specimen’s OA of the hip and knee were graded using a previously described method. PI was measured from standardised lateral photographs of reconstructed pelvises. Multiple regression analysis was performed to determine the relationship between age and PI with HOA and KOA.Objectives
Methods
The purpose of this study was to evaluate the long-term outcome
of adolescents with cerebral palsy who have undergone single-event
multilevel surgery for a flexed-knee gait, followed into young adulthood
using 3D motion analysis. A total of 59 young adults with spastic cerebral palsy, with
a mean age of 26 years (Aims
Patients and Methods
Adolescent idiopathic scoliosis (AIS) is a complex
3D deformity of the spine. Its prevalence is between 2% and 3% in the
general population, with almost 10% of patients requiring some form
of treatment and up to 0.1% undergoing surgery. The cosmetic aspect
of the deformity is the biggest concern to the patient and is often
accompanied by psychosocial distress. In addition, severe curves
can cause cardiopulmonary distress. With proven benefits from surgery,
the aims of treatment are to improve the cosmetic and functional
outcomes. Obtaining correction in the coronal plane is not the only
important endpoint anymore. With better understanding of spinal
biomechanics and the long-term effects of multiplanar imbalance,
we now know that sagittal balance is equally, if not more, important.
Better correction of deformities has also been facilitated by an
improvement in the design of implants and a better understanding
of metallurgy. Understanding the unique character of each deformity
is important. In addition, using the most appropriate implant and
applying all the principles of correction in a bespoke manner is important
to achieve optimum correction. In this article, we review the current concepts in AIS surgery. Cite this article:
The October 2014 Hip &
Pelvis Roundup360 looks at: functional acetabular orientation; predicting re-admission following THR; metal ions and resurfacing; lipped liners increase stability; all anaesthetics equal in hip fracture surgery; revision hip surgery in very young patients; and uncemented hips.
The orientation of the acetabular component is
influenced not only by the orientation at which the surgeon implants
the component, but also the orientation of the pelvis at the time
of implantation. Hence, the orientation of the pelvis at set-up
and its movement during the operation, are important. During 67
hip replacements, using a validated photogrammetric technique, we
measured how three surgeons orientated the patient’s pelvis, how
much the pelvis moved during surgery, and what effect these had
on the final orientation of the acetabular component. Pelvic orientation
at set-up, varied widely (mean (± 2, standard deviation ( Cite this article:
It has recently been reported that the transverse
acetabular ligament (TAL) is helpful in determining the position
of the acetabular component in total hip replacement (THR). In this
study we used a computer-assisted navigation system to determine
whether the TAL is useful as a landmark in THR. The study was carried
out in 121 consecutive patients undergoing primary THR (134 hips),
including 67 dysplastic hips (50%). There were 26 men (29 hips)
and 95 women (105 hips) with a mean age of 60.2 years (17 to 82)
at the time of operation. After identification of the TAL, its anteversion
was measured intra-operatively by aligning the inferomedial rim
of the trial acetabular component with the TAL using computer-assisted
navigation. The TAL was identified in 112 hips (83.6%). Intra-observer reproducibility
in the measurement of anteversion of the TAL was high, but inter-observer
reproducibility was moderate. Each surgeon was able to align the trial component according
to the target value of the angle of anteversion of the TAL, but
it was clear that methods may differ among surgeons. Of the measurements
of the angle of anteversion of the TAL, 5.4% (6 of 112 hips) were
outliers from the safe zone. In summary, we found that the TAL is useful as a landmark when
implanting the acetabular component within the safe zone in almost
all hips, and to prevent it being implanted in retroversion in all
hips, including dysplastic hips. However, as anteversion of the
TAL may be excessive in a few hips, it is advisable to pay attention
to individual variations, particularly in those with severe posterior
pelvic tilt. Cite this article:
Several radiological methods of measuring anteversion
of the acetabular component after total hip replacement (THR) have
been described. These studies used different definitions and reference
planes to compare methods, allowing for misinterpretation of the
results. We compared the reliability and accuracy of five current
methods using plain radiographs (those of Lewinnek, Widmer, Liaw,
Pradhan, and Woo and Morrey) with CT measurements, using the same
definition and reference plane. We retrospectively studied the plain
radiographs and CT scans in 84 hips of 84 patients who underwent
primary THR. Intra- and inter-observer reliability were high for
the measurement of inclination and anteversion with all methods
on plain radiographs and CT scans. The measurements of inclination on
plain radiographs were similar to the measurements using CT (p =
0.043). The mean difference between CT measurements was 0.6° (-5.9°
to 6.8°). Measurements using Widmer’s method were the most similar to those
using CT (p = 0.088), with a mean difference between CT measurements
of -0.9° (-10.4° to 9.1°), whereas the other four methods differed
significantly from those using CT (p <
0.001). This study has shown that Widmer’s method is the best for evaluating
the anteversion of the acetabular component on plain radiographs. Cite this article:
