Instability after total knee replacement (TKR)
accounts for 10% to 22% of revision procedures. All patients who
present for evaluation of instability require a thorough history to
be taken and physical examination, as well as appropriate imaging.
Deep periprosthetic infection must be ruled out by laboratory testing
and an aspiration of the knee must be carried out. The three main
categories of instability include flexion instability, extension instability
(symmetric and asymmetric), and genu recurvatum. Most recently,
the aetiologies contributing to, and surgical manoeuvres required
to correct, flexion instability have been elucidated. While implant
design and patient-related factors may certainly contribute to the
aetiology, surgical technique is also a significant factor in all
forms of post-operative instability. Cite this article:
Coronal plane fractures of the posterior femoral
condyle, also known as Hoffa fractures, are rare. Lateral fractures are
three times more common than medial fractures, although the reason
for this is not clear. The exact mechanism of injury is likely to
be a vertical shear force on the posterior femoral condyle with
varying degrees of knee flexion. These fractures are commonly associated
with high-energy trauma and are a diagnostic and surgical challenge. Hoffa
fractures are often associated with inter- or supracondylar distal
femoral fractures and CT scans are useful in delineating the coronal
shear component, which can easily be missed. There are few recommendations
in the literature regarding the surgical approach and methods of
fixation that may be used for this injury. Non-operative treatment
has been associated with poor outcomes. The goals of treatment are
anatomical reduction of the articular surface with rigid, stable
fixation to allow early mobilisation in order to restore function.
A surgical approach that allows access to the posterior aspect of
the femoral condyle is described and the use of postero-anterior
lag screws with or without an additional buttress plate for fixation
of these difficult fractures. 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:
Our understanding of the origin of hip pain in
degenerative disorders of the hip, including primary osteoarthritis, avascular
necrosis and femoroacetabular impingement (FAI), is limited. We
undertook a histological investigation of the nociceptive innervation
of the acetabular labrum, ligamentum teres and capsule of the hip,
in order to prove pain- and proprioceptive-associated marker expression.
These structures were isolated from 57 patients who had undergone
elective hip surgery (44 labral samples, 33 ligamentum teres specimens,
34 capsular samples; in 19 patients all three structures were harvested).
A total of
15 000 histological sections were prepared that were investigated
immunohistochemically for the presence of protein S-100, 68 kDa
neurofilament, neuropeptide Y, nociceptin and substance P. The tissues
were evaluated in six representative areas. Within the labrum, pain-associated free nerve ending expression
was located predominantly at its base, decreasing in the periphery.
In contrast, the distribution within the ligamentum teres showed
a high local concentration in the centre. The hip capsule had an
almost homogeneous marker expression in all investigated areas. This study showed characteristic distribution profiles of nociceptive
and pain-related nerve fibres, which may help in understanding the
origin of hip pain. Cite this article:
The lack of an accurate, rapid diagnostic test
for mycobacterium tuberculosis (TB) is a major handicap in the management
of spinal TB. GeneXpert, a new, rapid molecular diagnostic test
is recommended as the first line investigation for suspected pulmonary
TB in areas with a high prevalence of HIV or drug resistance, yet
it has not been validated for the diagnosis of musculoskeletal TB. The aim of this study was to assess the accuracy of GeneXpert
in diagnosing spinal TB. A prospective clinical study of 69 consecutive adults with suspected
spinal TB was conducted at a tertiary hospital in an area with the
highest incidence and prevalence of TB in the world. GeneXpert was
used on tissue samples of the enrolled patients and its diagnostic
accuracy compared with a reference standard of tissue in liquid culture.
A total of 71 spine samples from 69 patients (two re-biopsies) were
included in the study. The GeneXpert test showed a sensitivity of 95.6% and specificity
of 96.2% for spinal TB. The results of the GeneXpert test were available
within 48 hours compared with a median of 35 days (IQR 15 to 43)
for cultures. All cases of multi-drug resistant TB (MDR TB) were
diagnosed accurately with the GeneXpert test. The MDR TB rate was
5.8%. Cite this article:
Degenerative problems of the hip in patients
with childhood and adult onset neuromuscular disorders can be challenging
to treat. Many orthopaedic surgeons are reluctant to recommend total
hip replacement (THR) for patients with underlying neuromuscular
disorders due to the perceived increased risks of dislocation, implant loosening,
and lack of information about the functional outcomes and potential
benefits of these procedures in these patients. Modular femoral
components and alternative bearings which facilitate the use of
large femoral heads, constrained acetabular components and perhaps
more importantly, a better understanding about the complications
and outcomes of THR in the patient with neuromuscular disorders,
make this option viable. This paper will review the current literature
and our experience with THR in the more frequently encountered neuromuscular
disorders. Cite this article:
Deficiency of the abductor mechanism is a well-recognised
cause of pain and limping after total hip replacement (THR). This
can be found incidentally at the time of surgery, or it may arise
as a result of damage to the superior gluteal nerve intra-operatively,
or after surgery owing to mechanical failure of the abductor muscle
repair or its detachment from the greater trochanter. The incidence
of abductor failure has been reported as high as 20% in some studies.
The management of this condition remains a dilemma for the treating
surgeon. We review the current state of knowledge concerning post-THR
abductor deficiency, including the aetiology, diagnosis and management,
and the outcomes of surgery for this condition. Cite this article:
There is a high risk of the development of avascular
necrosis of the femoral head and nonunion after the treatment of
displaced subcapital fractures of the femoral neck in patients aged
<
50 years. We retrospectively analysed the results following
fixation with two cannulated compression screws and a vascularised
iliac bone graft. We treated 18 women and 16 men with a mean age
of 38.5 years (20 to 50) whose treatment included the use of an
iliac bone graft based on the ascending branch of lateral femoral
circumflex artery. There were 20 Garden grade III and 14 grade IV
fractures. Clinical and radiological outcomes were evaluated. The
mean follow-up was 5.4 years (2 to 10). In 30 hips (88%) union was
achieved at a mean of 4.4 months (4 to 6). Nonunion occurred in
four hips (12%) and these patients had a mean age of 46.5 years
(42 to 50) and underwent revision to a hip replacement six months
after operation. The time to union was dependent on age with younger
patients achieving earlier union (p <
0.001). According to the
Harris hip score which was available for 27 of the 30 hips with
satisfactory union, excellent results were obtained in 15 (score ≥ 90
points), fair in ten (score 80 to 90 points), and poor in two hips
(≤ 80 points). One patient aged 48 years developed avascular necrosis
of femoral head six years after operation and underwent total hip
replacement. The management of displaced subcapital fractures of the femoral
neck, in patients aged <
50 years, with two cannulated compression
screws and an iliac bone graft based on the ascending branch of
lateral femoral circumflex artery, gives satisfactory results with
a low rate of complication including avascular necrosis and nonunion. Cite this article:
We have reviewed 42 patients who had revision of metal-on-metal resurfacing procedures, mostly because of problems with the acetabular component. The revisions were carried out a mean of 26.2 months (1 to 76) after the initial operation and most of the patients (30) were female. Malpositioning of the acetabular component resulted in 27 revisions, mostly because of excessive abduction (mean 69.9°; 56° to 98°) or insufficient or excessive anteversion. Seven patients had more than one reason for revision. The mean increase in the diameter of the component was 1.8 mm (0 to 4) when exchange was needed. Malpositioning of the components was associated with metallosis and a high level of serum ions. The results of revision of the femoral component to a component with a modular head were excellent, but four patients had dislocation after revision and four required a further revision.
We retrospectively reviewed 89 consecutive patients
(45 men and 44 women) with a mean age at the time of injury of 58
years (18 to 97) who had undergone external fixation after sustaining
a unilateral fracture of the distal humerus. Our objectives were
to determine the incidence of heterotopic ossification (HO); identify
risk factors associated with the development of HO; and characterise
the location, severity and resultant functional impairment attributable
to the presence of HO. HO was identified in 37 elbows (42%), mostly around the humerus
and along the course of the medial collateral ligament. HO was hazy
immature in five elbows (13.5%), mature discrete in 20 (54%), extensive
mature in 10 (27%), and complete bone bridges were present in two
elbows (5.5%). Mild functional impairment occurred in eight patients,
moderate in 27 and severe in two. HO was associated with less extension
(p = 0.032) and less overall flexion-to-extension movement (p =
0.022); the flexion-to-extension arc was <
100º in 21 elbows
(57%) with HO compared with 18 elbows (35%) without HO (p = 0.03).
HO was removed surgically in seven elbows. The development of HO was significantly associated with sustaining
a head injury (p = 0.015), delayed internal fixation (p = 0.027),
the method of fracture fixation (p = 0.039) and the use of bone
graft or substitute (p = 0.02).HO continues to be a substantial
complication after internal fixation for distal humerus fractures. Cite this article:
The aim of this study was to determine whether
an osteoplasty of the femoral neck performed at the same time as an
intertrochanteric Imhäuser osteotomy led to an improved functional
outcome or increased morbidity. A total of 20 hips in 19 patients
(12 left, 8 right, 13 male, 6 female), who underwent an Imhäuser
intertrochanteric osteotomy following a slipped capital femoral
epiphysis were assessed over an eight-year period. A total of 13
hips in 13 patients had an osteoplasty of the femoral neck at the
same time. The remaining six patients (seven hips) had intertrochanteric
osteotomy alone. The mean age was 15.3 years (13 to 20) with a mean
follow-up of 57.8 months (15 to 117); 19 of the slips were severe
(Southwick grade III) and one was moderate (grade II), with a mean
slip angle of 65.3° (50° to 80°); 17 of the slips were stable and
three unstable at initial presentation. The mean Non-Arthritic Hip Scores
(NAHS) in patients who underwent osteoplasty was 91.7 (76.3 to 100)
and the mean NAHS in patients who did not undergo osteoplasty was
76.6 (41.3 to 100) (p = 0.056). Two patients required a subsequent
arthroplasty and neither of these patients had an osteoplasty. No
hips developed osteonecrosis or chondrolysis, and there was no increase
in complications related to the osteoplasty. We recommend that for
patients with a slipped upper femoral epiphysis undergoing an intertrochanteric
osteotomy, the addition of an osteoplasty of the femoral neck should
be considered. Cite this article:
During hip resurfacing arthroplasty, excessive valgus positioning or surgical technique can result in notching of the femoral neck. Although mechanical weakening and subsequent fracture of the femoral neck are well described, the potential damage to the retinacular vessels leading to an ischaemic event is relatively unknown. Using laser Doppler flowmetry, we measured the blood flow in 14 osteoarthritic femoral heads during routine total hip replacement surgery, before and after notching of the femoral neck. In ten hips there was a reduction in blood flow of more than 50% from the baseline value after simulated notching of the femoral neck. Our results suggest that femoral head vascularity in the osteoarthritic state is similar to the non-arthritic state, where damage to the extraosseous vessels can predispose to avascular necrosis. Surgeons who perform resurfacing arthroplasty of the hip should pay careful attention to these vessels by avoiding excessive dissection around the femoral neck and/or notching.
Proximal femoral varus osteotomy improves the
biomechanics of the hip and can stimulate normal acetabular development
in a dysplastic hip. Medial closing wedge osteotomy remains the
most popular technique, but is associated with shortening of the
ipsilateral femur. We produced a trigonometric formula which may be used pre-operatively
to predict the resultant leg length discrepancy (LLD). We retrospectively
examined the influence of the choice of angle in a closing wedge
femoral osteotomy on LLD in 120 patients (135 osteotomies, 53% male,
mean age six years, (3 to 21), 96% caucasian) over a 15-year period
(1998 to 2013). A total of 16 of these patients were excluded due
to under or over varus correction. The patients were divided into
three age groups: paediatric (<
10 years), adolescent (10 to
16 years) and adult (>
16 years). When using the same saw blades
as in this series, the results indicated that for each 10° of angle
of resection the resultant LLD equates approximately to multiples
of 4 mm, 8 mm and 12 mm in the three age groups, respectively. Statistical testing of the 59 patients who had a complete set
of pre- and post-operative standing long leg radiographs, revealed
a Pearson’s correlation coefficient for predicted This study identified a geometric model that provided satisfactory
accuracy when using specific saw blades of known thicknesses for
this formula to be used in clinical practice. Cite this article:
The dismal outcome of tuberculosis of the spine in the pre-antibiotic era has improved significantly because of the use of potent antitubercular drugs, modern diagnostic aids and advances in surgical management. MRI allows the diagnosis of a tuberculous lesion, with a sensitivity of 100% and specificity of 88%, well before deformity develops. Neurological deficit and deformity are the worst complications of spinal tuberculosis. Patients treated conservatively show an increase in deformity of about 15°. In children, a kyphosis continues to increase with growth even after the lesion has healed. Tuberculosis of the spine is a medical disease which is not primarily treated surgically, but operation is required to prevent and treat the complications. Panvertebral lesions, therapeutically refractory disease, severe kyphosis, a developing neurological deficit, lack of improvement or deterioration are indications for surgery. Patients who present with a kyphosis of 60° or more, or one which is likely to progress, require anterior decompression, posterior shortening, posterior instrumented stabilisation and anterior and posterior bone grafting in the active stage of the disease. Late-onset paraplegia is best prevented rather than treated. The awareness and suspicion of an atypical presentation of spinal tuberculosis should be high in order to obtain a good outcome. Therapeutically refractory cases of tuberculosis of the spine are increasing in association with the presence of HIV and multidrug-resistant tuberculosis.
Metal-on-metal hip resurfacing (MOMHR) is available as an alternative
option for younger, more active patients. There are failure modes
that are unique to MOMHR, which include loosening of the femoral
head and fractures of the femoral neck. Previous studies have speculated
that changes in the vascularity of the femoral head may contribute
to these failure modes. This study compares the survivorship between
the standard posterior approach (SPA) and modified posterior approach
(MPA) in MOMHR. A retrospective clinical outcomes study was performed examining
351 hips (279 male, 72 female) replaced with Birmingham Hip Resurfacing
(BHR, Smith and Nephew, Memphis, Tennessee) in 313 patients with
a pre-operative diagnosis of osteoarthritis. The mean follow-up
period for the SPA group was 2.8 years (0.1 to 6.1) and for the
MPA, 2.2 years (0.03 to 5.2); this difference in follow-up period
was statistically significant (p <
0.01). Survival analysis was
completed using the Kaplan–Meier method. Objectives
Methods
Unstable bicondylar tibial plateau fractures
are rare and there is little guidance in the literature as to the
best form of treatment. We examined the short- to medium-term outcome
of this injury in a consecutive series of patients presenting to
two trauma centres. Between December 2005 and May 2010, a total
of 55 fractures in 54 patients were treated by fixation, 34 with
peri-articular locking plates and 21 with limited access direct
internal fixation in combination with circular external fixation
using a Taylor Spatial Frame (TSF). At a minimum of one year post-operatively,
patient-reported outcome measures including the WOMAC index and
SF-36 scores showed functional deficits, although there was no significant
difference between the two forms of treatment. Despite low outcome scores,
patients were generally satisfied with the outcome. We achieved
good clinical and radiological outcomes, with low rates of complication.
In total, only three patients (5%) had collapse of the joint of
>
4 mm, and metaphysis to diaphysis angulation of greater than 5º,
and five patients (9%) with displacement of >
4 mm. All patients
in our study went on to achieve full union. This study highlights the serious nature of this injury and generally
poor patient-reported outcome measures following surgery, despite
treatment by experienced surgeons using modern surgical techniques.
Our findings suggest that treatment of complex bicondylar tibial
plateau fractures with either a locking plate or a TSF gives similar
clinical and radiological outcomes. Cite this article:
Metal-on-metal (MoM) hip resurfacing was developed in the 1990s by surgeons in Birmingham, UK, as a surgical solution to the problem of osteoarthritis in younger, more active patients. Early results were promising and the procedure gained in popularity. However, adverse reports of soft-tissue reaction and failure started to appear from 2008 onwards. Surgeons may be asked to write medico-legal reports on the surgical aspects of an individual case for claimant lawyers or in defence for the NHSLA or indemnity insurers. The purpose of this article is to cover some of the aspects of the operation that may be considered in such medico-legal reports.
In this case study, we describe the clinical
presentation and treatment of 36 patients with periosteal chondrosarcoma
collected over a 59-year period by the archive of the Netherlands
Committee on Bone Tumours. The demographics, clinical presentation,
radiological features, treatment and follow-up are presented with
the size, location, the histological grading of the tumour and the
survival. We found a slight predominance of men (61%), and a predilection
for the distal femur (33%) and proximal humerus (33%). The metaphysis
was the most common site (47%) and the most common presentation
was with pain (44%). Half the tumours were classified histologically
as grade 1. Pulmonary metastases were reported in one patient after
an intra-lesional resection. A second patient died from local recurrence
and possible pulmonary and skin metastases after an incomplete resection. It is clearly important to make the diagnosis appropriately because
an incomplete resection may result in local recurrence and metastatic
spread. Staging for metastatic disease is recommended in grade II
or III lesions. These patients should be managed with a contrast-enhanced MRI
of the tumour and histological confirmation by biopsy, followed
by Cite this article:
The June 2014 Children’s orthopaedics Roundup360 looks at: plaster wedging in paediatric forearm fractures; the medial approach for DDH; Ponseti – but not as he knew it?; Salter osteotomy more accurate than Pemberton in DDH; is the open paediatric fracture an emergency?; bang up-to-date with femoral external fixation; indomethacin, heterotopic ossification and cerebral palsy hips; lengthening nails for congenital femoral deformities, and is MRI the answer to imaging of the physis?
We undertook a retrospective cohort study to
determine clinical outcomes following the revision of metal-on-metal (MoM)
hip replacements for adverse reaction to metal debris (ARMD), and
to identify predictors of time to revision and outcomes following
revision. Between 1998 and 2012 a total of 64 MoM hips (mean age
at revision of 57.8 years; 46 (72%) female; 46 (72%) hip resurfacings
and 18 (28%) total hip replacements) were revised for ARMD at one specialist
centre. At a mean follow-up of 4.5 years (1.0 to 14.6) from revision
for ARMD there were 13 hips (20.3%) with post-operative complications
and eight (12.5%) requiring re-revision. The Kaplan–Meier five-year survival rate for ARMD revision was
87.9% (95% confidence interval 78.9 to 98.0; 19 hips at risk). Excluding
re-revisions, the median absolute Oxford hip score (OHS) following
ARMD revision using the percentage method (0% best outcome and 100%
worst outcome) was 18.8% (interquartile range (IQR) 7.8% to 48.3%),
which is equivalent to 39/48 (IQR 24.8/48 to 44.3/48) when using
the modified OHS. Histopathological response did not affect time
to revision for ARMD (p = 0.334) or the subsequent risk of re-revision
(p = 0.879). Similarly, the presence or absence of a contralateral
MoM hip bearing did not affect time to revision for ARMD (p = 0.066)
or the subsequent risk of re-revision (p = 0.178). Patients revised to MoM bearings had higher rates of re-revision
(five of 16 MoM hips re-revised; p = 0.046), but those not requiring
re-revision had good functional results (median absolute OHS 14.6%
or 41.0/48). Short-term morbidity following revision for ARMD was
comparable with previous reports. Caution should be exercised when choosing
bearing surfaces for ARMD revisions. Cite this article: