Osteoporosis and abnormal bone metabolism may prove to be significant
factors influencing the outcome of arthroplasty surgery, predisposing
to complications of aseptic loosening and peri-prosthetic fracture.
We aimed to investigate baseline bone mineral density (BMD) and
bone turnover in patients about to undergo arthroplasty of the hip
and knee. We prospectively measured bone mineral density of the hip and
lumbar spine using dual-energy X-ray absorptiometry (DEXA) scans
in a cohort of 194 patients awaiting hip or knee arthroplasty. We
also assessed bone turnover using urinary deoxypyridinoline (DPD),
a type I collagen crosslink, normalised to creatinine.Aims
Methods
Peripheral nerve injury is an uncommon but serious
complication of hip surgery that can adversely affect the outcome.
Several studies have described the use of electromyography and intra-operative
sensory evoked potentials for early warning of nerve injury. We
assessed the results of multimodal intra-operative monitoring during
complex hip surgery. We retrospectively analysed data collected
between 2001 and 2010 from 69 patients who underwent complex hip
surgery by a single surgeon using multimodal intra-operative monitoring
from a total pool of 7894 patients who underwent hip surgery during
this period. In 24 (35%) procedures the surgeon was alerted to a
possible lesion to the sciatic and/or femoral nerve. Alerts were
observed most frequently during peri-acetabular osteotomy. The surgeon
adapted his approach based on interpretation of the neurophysiological changes.
From 69 monitored surgical procedures, there was only one true positive
case of post-operative nerve injury. There were no false positives
or false negatives, and the remaining 68 cases were all true negative.
The sensitivity for predicting post-operative nerve injury was 100%
and the specificity 100%. We conclude that it is possible and appropriate
to use this method during complex hip surgery and it is effective
for alerting the surgeon to the possibility of nerve injury.
Between November 1997 and December 2000 we performed 27 total hip replacements in 22 patients with high congenital dislocation of the hip using porous tantalum monoblock acetabular components implanted in the true acetabular bed. Clinical and radiological evaluation was performed at regular intervals for a mean of 10.2 years (8.5 to 12). The mean Harris Hip Score improved from 48.3 (15 to 65) pre-operatively to 89.5 (56 to 100) at the final follow-up. The mean Oxford Hip Score was 49.5 (35 to 59) pre-operatively and decreased to 21.2 (12 to 48) at one year and 15.2 (10 to 28) at final follow-up. Migration of the acetabular component was assessed with the EBRA software system. There was a mean migration of 0.68 mm (0.49 to 0.8) in the first year and a mean 0.89 mm (0.6 to 0.98) in the second year, after excluding one initial excessive migration. No revision was necessary for any reason, no acetabular component became loose, and no radiolucent lines were observed at the final follow-up. The porous tantalum monoblock acetabular component is an implant offering adequate initial stability in conjunction with a modulus of elasticity and porosity close to that of cancellous bone. It favours bone ingrowth, leading to good mid-term results.
Diastematomyelia is a rare congenital abnormality
of the spinal cord. This paper summarises more than 30 years’ experience
of treating this condition. Data were collected retrospectively
on 138 patients with diastematomyelia (34 males, 104 females) who
were treated at our hospital from May 1978 to April 2010. A total
of 106 patients had double dural
The October 2013 Hip &
Pelvis Roundup360 looks at: Young and impinging; Clothes, weather and femoral heads?; Go long, go cemented; Surgical repair of the abductors?; Aspirin for DVT prophylaxis?; Ceramic-on-polyethylene: a low-wear solution?; ALVAL and ASR™: the story continues….; Salvaging Legg-Calve-Perthes’ disease
The incidence of clinically significant avascular
necrosis (AVN) following medial open reduction of the dislocated
hip in children with developmental dysplasia of the hip (DDH) remains
unknown. We performed a systematic review of the literature to identify
all clinical studies reporting the results of medial open reduction
surgery. A total of 14 papers reporting 734 hips met the inclusion
criteria. The mean follow-up was 10.9 years (2 to 28). The rate
of clinically significant AVN (types 2 to 4) was 20% (149/734).
From these papers 221 hips in 174 children had sufficient information
to permit more detailed analysis. The rate of AVN increased with
the length of follow-up to 24% at skeletal maturity, with type 2
AVN predominating in hips after five years’ follow-up. The presence
of AVN resulted in a higher incidence of an unsatisfactory outcome
at skeletal maturity (55% Cite this article:
We have investigated the benefits of patient
specific instrument guides, applied to osteotomies around the knee. Single,
dual and triple planar osteotomies were performed on tibias or femurs
in 14 subjects. In all patients, a detailed pre-operative plan was
prepared based upon full leg standing radiographic and CT scan information.
The planned level of the osteotomy and open wedge resection was
relayed to the surgery by virtue of a patient specific guide developed
from the images. The mean deviation between the planned wedge angle
and the executed wedge angle was 0° (-1 to 1, Cite this article:
We investigated the eventual diagnosis in patients referred to a tertiary centre with a possible diagnosis of a primary bone malignancy. We reviewed our database from between 1986 and 2010, during which time 5922 patients referred with a suspicious bone lesion had a confirmed diagnosis. This included bone sarcoma in 2205 patients (37%), benign bone tumour in 1309 (22%), orthopaedic conditions in 992 (17%), metastatic disease in 533 (9%), infection in 289 (5%) and haematological disease in 303 (5%). There was a similar frequency of all diagnoses at different ages except for metastatic disease. Only 0.6% of patients (17 of 2913) under the age of 35 years had metastatic disease compared with 17.1% (516 of 3009) of those over 35 years (p <
0.0001). Of the 17 patients under 35 years with metastatic disease, only four presented with an isolated lesion, had no past history of cancer and were systematically well. Patients under the age of 35 years should have suitable focal imaging (plain radiography, CT or MRI) and simple systemic studies (blood tests and chest radiography). Reduction of the time to biopsy can be achieved by avoiding an unnecessary investigation for a primary tumour to rule out metastatic disease.
We have reviewed the current literature to compare
the results of surgery aimed to repair or debride a damaged acetabular
labrum. We identified 28 studies to be included in the review containing
a total of 1631 hips in 1609 patients. Of these studies 12 reported
a mean rate of good results of 82% (from 67% to 100%) for labral debridement.
Of the 16 studies that reported a combination of debridement and
re-attachment, five reported a comparative outcome for the two methods,
four reported better results with re-attachment and one study did
not find any significant difference in outcomes. Due to the heterogeneity
of the studies it was not possible to perform a meta-analysis or
draw accurate conclusions. Confounding factors in the studies include
selection bias, use of historical controls and high rates of loss
of follow-up. It seems logical to repair an unstable tear in a good quality
labrum with good potential to heal in order potentially to preserve
its physiological function. A degenerative labrum on the other hand
may be the source of discomfort and its preservation may result
in persistent pain and the added risk of failure of re-attachment.
The results of the present study do not support routine refixation
for all labral tears. Cite this article:
We have undertaken a prospective, randomised study to compare conservation of acetabular bone after total hip replacement and resurfacing arthroplasty of the hip. We randomly assigned 210 hips to one of the two treatment groups. Uncemented, press-fit acetabular components were used for both. No significant difference was found in the mean diameter of acetabular implant inserted in the groups (54.74 mm for total hip replacement and 54.90 mm for resurfacing arthroplasty). In seven resurfacing procedures (6.8%), the surgeon used a larger size of component in order to match the corresponding diameter of the femoral component. With resurfacing arthroplasty, conservation of bone is clearly advantageous on the femoral side. Our study has shown that, with a specific design of acetabular implant and by following a careful surgical technique, removal of bone on the acetabular side is comparable with that of total hip replacement.
We have reviewed the literature to establish the role of lateral retinacular release in the management of disorders of the extensor apparatus of the knee. The scientific evidence for intervention is explored and reports on outcome are discussed.
The aim of this study was to define the incidence
of venous thromboembolism (VTE) and risk factors for the development
of deep-vein thrombosis (DVT) after the resection of a musculoskeletal
tumour. A total of 94 patients who underwent resection of a musculoskeletal
tumour between January 2003 and December 2005 were prospectively
studied. There were 42 men and 52 women with a mean age of 54.4
years (18 to 86). All patients wore intermittent pneumatic compression
devices and graduated compression stockings. Ultrasound examination
of the lower limbs was conducted to screen for DVT between the fifth
and ninth post-operative days. DVT was detected in 21 patients (22%). Of these, two were symptomatic
(2%). One patient (1%) had a fatal pulmonary embolism. Patients
aged ≥ 70 years had an increased risk of DVT (p = 0.004). The overall incidence of DVT (both symptomatic and asymptomatic)
after resection of a musculoskeletal tumour with mechanical prophylaxis
was high. It seems that both mechanical and anticoagulant prophylaxis
is needed to prevent VTE in patients who have undergone the resection
of a musculoskeletal tumour. Cite this article:
We compared the dynamic instability of 25 dysplastic hips in 25 patients using triaxial accelerometry before and one year after periacetabular osteotomy. We also evaluated the hips clinically using the Harris hip score and assessed acetabular orientation by radiography before surgery and after one year. The mean overall magnitude of acceleration was significantly reduced from 2.30 m/s This study suggests that periacetabular osteotomy provides pain relief, improves acetabular cover and reduces the dynamic instability in patients with dysplastic hips.
Most centres in the United Kingdom adopt a selective
screening programme for developmental dysplasia of the hip (DDH)
based on repeated clinical examination and selective ultrasound
examination. The Newborn Infant Physical Examination protocol implemented
in 2008 recommends a first examination at birth and then a second
and final examination at six to ten weeks of age. Due to concerns
over an increase in late presentations we performed a retrospective
review of our 15-year results to establish if late presentation
increases treatment requirements. Of children presenting before
six weeks of age, 84% were treated successfully with abduction bracing,
whereas 86% of children presenting after ten months eventually required
open reduction surgery. This equates to a 12-fold increase in relative
risk of requiring open reduction following late presentation. Increasing
age at presentation was associated with an increase in the number
of surgical procedures, which are inevitably more extensive and complex,
with a consequent increased in cost per patient. The implementation
of an opportunistic examination at three to five months could help
to reduce the unintended consequences of the Newborn Infant Physical Examination
programme. Cite this article:
Total hip replacement for high dislocation of the hip joint remains technically difficult in terms of preparation of the true acetabulum and restoration of leg length. We describe our experience of cementless total hip replacement combined with a subtrochanteric femoral shortening osteotomy in 20 hips with Crowe grade IV dislocation with a mean follow-up of 8.1 years (4 to 11.5). There was one man and 17 women with a mean age of 55 years (44 to 69) at the time of the operation. After placment of the acetabular component at the site of the natural acetabulum, a cementless porous-coated cylindrical femoral component was implanted following a subtrochanteric femoral shortening osteotomy. The mean Japanese Orthopedic Association hip score improved from a mean of 38 (22 to 62) to a mean of 83 points (55 to 98) at the final follow-up. The mean lengthening of the leg was 14.8 mm (−9 to 34) in patients with iliofemoral osteoarthritis and 35.3 mm (15 to 51) in patients with no arthritic changes. No nerve palsy was observed. Total hip replacement combined with subtrochanteric shortening femoral osteotomy in this situation is beneficial in avoiding nerve injury and still permits valuable improvement in inequality of leg length.
We report the long-term survival and functional
outcome of the Birmingham Hip Resurfacing (BHR) in patients aged <
50 years at operation, and explore the factors affecting survival.
Between 1997 and 2006, a total of 447 BHRs were implanted in 393
patients (mean age 41.5 years (14.9 to 49.9)) by one designing surgeon.
The mean follow-up was 10.1 years (5.2 to 14.7), with no loss to
follow-up. In all, 16 hips (3.6%) in 15 patients were revised, giving
an overall cumulative survival of 96.3% (95% confidence interval
(CI) 93.7 to 98.3) at ten years and 94.1% (95% CI 84.9 to 97.3)
at 14 years. Using aseptic revision as the endpoint, the survival
for men with primary osteoarthritis (n = 195) was 100% (95% CI 100
to 100) at both ten years and 14 years, and in women with primary
osteoarthritis (n = 109) it was 96.1% (95% CI 90.1 to 99.9) at ten
years and 91.2% (95% CI 68.6 to 98.7) at 14 years. Female gender
(p = 0.047) and decreasing femoral head size (p = 0.044) were significantly
associated with an increased risk of revision. The median Oxford
hip score (OHS, modified as a percentage with 100% indicating worst
outcome) at last follow-up was 4.2% (46 of 48; interquartile range
(IQR) 0% to 24%) and the median University of California, Los Angeles
(UCLA) score was 6.0 (IQR 5 to 8). Men had significantly better
OHS (p = 0.02) and UCLA scores (p = 0.01) than women. The BHR provides
excellent survival and functional results in men into the second
decade, with good results achieved in appropriately selected women. Cite this article:
We evaluated the outcome of 41 consecutive Charnley
low-friction arthroplasties (LFAs) performed by a single surgeon
in 28 patients aged ≤ 35 years at operation between 23 and 36 years
previously. There were 20 women and eight men with a mean age of
32 years (23 to 35) at surgery. Two patients (three hips) were lost
to follow-up at 12 and 17 years post-operatively, respectively,
and one patient (one hip) died at 13 years post-operatively. These patients
were excluded from the final evaluation. The survival rate of the
acetabular components was 92.7% (95% confidence interval (CI) 88.7
to 96.7) at ten years, 67.1% (95% CI 59.75 to 74.45) at 20 years
and 53.2% (95% CI 45.3 to 61.1) at 25 years. For the femoral component
the survival was 95.1% (95% CI 91.8 to 98.5) at ten years, 77.1%
(95% CI 73.9 to 80.3) at 20 years and 68.2% (95% CI 60.7 to 75.8)
at 25 years. The results indicate that the Charnley LFA remains
a reasonable choice in the treatment of young patients and can serve
for comparison with newer techniques and implants. Cite this article:
Patella subluxation assessed on dynamic MRI has
previously been shown to be associated with anterior knee pain. In
this MRI study of 60 patients we investigated the relationship between
subluxation and multiple bony, cartilaginous and soft-tissue factors
that might predispose to subluxation using discriminant function
analysis. Patella engagement (% of patella cartilage overlapping with trochlea
cartilage) had the strongest relationship with subluxation. Patellae
with >
30% engagement tended not to sublux; those with <
30%
tended to sublux. Other factors that were associated with subluxation
included the tibial tubercle-trochlea notch distance, vastus medialis obliquus
distance from patella, patella alta, and the bony and cartilaginous
sulcus angles in the superior part of the trochlea. No relationship
was found between subluxation and sulcus angles for cartilage and
bone in the middle and lower part of the trochlea, cartilage thicknesses
and Wiberg classification of the patella. This study indicates that patella engagement is a key factor
associated with patellar subluxation. This suggests that in patients
with anterior knee pain with subluxation, resistant to conservative
management, surgery directed towards improving patella engagement
should be considered. A clinical trial is necessary to test this
hypothesis.
The June 2013 Children’s orthopaedics Roundup360 looks at: whether reaching a diagnosis is more difficult than previously thought; adolescent and paediatric DDH; the A-frame orthosis and Legg-Calvé-Perthes’ disease; failure of hip surgery in patients with cerebral palsy; adolescent rotator cuff injuries; paediatric peripheral nerve injuries; predicting residual deformity following Ponseti treatment; and the Dunn procedure.