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:
We scanned 25 left knees in healthy human subjects
using MRI. Multiplanar reconstruction software was used to take
measurements of the inferior and posterior facets of the femoral
condyles and the trochlea. A ‘basic circle’ can be defined which, in the sagittal plane,
fits the posterior and inferior facets of the lateral condyle, the
posterior facet of the medial condyle and the floor of the groove
of the trochlea. It also approximately fits both condyles in the
coronal plane (inferior facets) and the axial plane (posterior facets).
The circle fitting the inferior facet of the medial condyle in the
sagittal plane was consistently 35% larger than the other circles
and was termed the ‘medial inferior circle’. There were strong correlations
between the radii of the circles, the relative positions of the
centres of the condyles, the width of the condyles, the total knee
width and skeletal measurements including height. There was poor
correlation between the radii of the circles and the position of
the trochlea relative to the condyles. In summary, the condyles are approximately spherical except for
the inferior facet medially, which has a larger radius in the sagittal
plane. The size and position of the condyles are consistent and
change with the size of the person. However, the position of the
trochlea is variable even though its radius is similar to that of
the condyles. This information has implications for understanding
anterior knee pain and for the design of knee replacements. Cite this article:
Large osteochondral lesions (OCLs) of the shoulder
of the talus cannot always be treated by traditional osteochondral
autograft techniques because of their size, articular geometry and
loss of an articular buttress. We hypothesised that they could be
treated by transplantation of a vascularised corticoperiosteal graft
from the ipsilateral medial femoral condyle. Between 2004 and 2011, we carried out a prospective study of
a consecutive series of 14 patients (five women, nine men; mean
age 34.8 years, 20 to 54) who were treated for an OCL with a vascularised
bone graft. Clinical outcome was assessed using a visual analogue
scale (VAS) for pain and the American Orthopaedic Foot and Ankle Society
(AOFAS) hindfoot score. Radiological follow-up used plain radiographs
and CT scans to assess graft incorporation and joint deterioration. At a mean follow-up of 4.1 years (2 to 7), the mean VAS for pain
had decreased from 5.8 (5 to 8) to 1.8 (0 to 4) (p = 0.001) and
the mean AOFAS hindfoot score had increased from 65 (41 to 70) to
81 (54 to 92) (p = 0.003). Radiologically, the talar contour had
been successfully reconstructed with stable incorporation of the
vascularised corticoperiosteal graft in all patients. Joint degeneration
was only seen in one ankle. Treatment of a large OCL of the shoulder of the talus with a
vascularised corticoperiosteal graft taken from the medial condyle
of the femur was found to be a safe, reliable method of restoring
the contour of the talus in the early to mid-term. Cite this article:
We investigated 60 patients (89 feet) with a
mean age of 64 years (61 to 67) treated for congenital clubfoot deformity,
using standardised weight-bearing radiographs of both feet and ankles
together with a functional evaluation. Talocalcaneal and talonavicular
relationships were measured and the degree of osteo-arthritic change
in the ankle and talonavicular joints was assessed. The functional
results were evaluated using a modified Laaveg-Ponseti score. The
talocalcaneal (TC) angles in the clubfeet were significantly lower
in both anteroposterior (AP) and lateral projections than in the
unaffected feet (p <
0.001 for both views). There was significant
medial subluxation of the navicular in the clubfeet compared with
the unaffected feet (p <
0.001). Severe osteoarthritis in the
ankle joint was seen in seven feet (8%) and in the talonavicular
joint in 11 feet (12%). The functional result was excellent or good
(≥ 80 points) in 29 patients (48%), and fair or poor (<
80 points)
in 31 patients (52%). Patients who had undergone few (0 to 1) surgical
procedures had better functional outcomes than those who had undergone
two or more procedures (p <
0.001). There was a significant correlation
between the functional result and the degree of medial subluxation
of the navicular (p <
0.001, r2 = 0.164), the talocalcaneal
angle on AP projection (p <
0.02, r2 = 0.025) and extent of osteoarthritis
in the ankle joint (p <
0.001). We conclude that poor functional outcome in patients with congenital
clubfoot occurs more frequently in those with medial displacement
of the navicular, osteoarthritis of the talonavicular and ankle
joints, and a low talocalcaneal angle on the AP projection, and
in patients who have undergone two or more surgical procedures. However,
the ankle joint in these patients appeared relatively resistant
to the development of osteoarthritis.
Using human cadaver specimens, we investigated
the role of supplementary fibular plating in the treatment of distal
tibial fractures using an intramedullary nail. Fibular plating is
thought to improve stability in these situations, but has been reported
to have increased soft-tissue complications and to impair union
of the fracture. We proposed that multidirectional locking screws
provide adequate stability, making additional fibular plating unnecessary.
A distal tibiofibular osteotomy model performed on matched fresh-frozen
lower limb specimens was stabilised with reamed nails using conventional
biplanar distal locking (CDL) or multidirectional distal locking
(MDL) options with and without fibular plating. Rotational stiffness
was assessed under a constant axial force of 150 N and a superimposed
torque of ± 5 Nm. Total movement, and neutral zone and fracture
gap movement were analysed. In the CDL group, fibular plating improved stiffness at the tibial
fracture site, albeit to a small degree (p = 0.013). In the MDL
group additional fibular plating did not increase the stiffness.
The MDL nail without fibular plating was significantly more stable
than the CDL nail with an additional fibular plate (p = 0.008). These findings suggest that additional fibular plating does not
improve stability if a multidirectional distal locking intramedullary
nail is used, and is therefore unnecessary if not needed to aid
reduction. Cite this article:
Radiological assessment of total and unicompartmental
knee replacement remains an essential part of routine care and follow-up.
Appreciation of the various measurements that can be identified
radiologically is important. It is likely that routine plain radiographs
will continue to be used, although there has been a trend towards
using newer technologies such as CT, especially in a failing knee,
where it provides more detailed information, albeit with a higher
radiation exposure. The purpose of this paper is to outline the radiological parameters
used to evaluate knee replacements, describe how these are measured
or classified, and review the current literature to determine their
efficacy where possible.
Periprosthetic joint infection (PJI) is one of
the most feared and challenging complications following total knee arthroplasty.
We provide a detailed description of our current understanding regarding
the management of PJI of the knee, including diagnostic aids,
pre-operative planning, surgical treatment, and outcome. Cite this article:
Peri-acetabular osteotomy is an established surgical
treatment for symptomatic acetabular dysplasia in young adults.
An anteroposterior radiograph of the pelvis is commonly used to
assess the extent of dysplasia as well as to assess post-operative
correction. Radiological prognostic factors include the lateral
centre-edge angle, acetabular index, extrusion index and the acetabular
version. Standing causes a change in the pelvis tilt which can alter
certain radiological measurements relative to the supine position.
This article discusses the radiological indices used to assess dysplasia
and reviews the effects of patient positioning on these indices
with a focus on assessment for a peri-acetabular osteotomy. Intra-operatively,
fluoroscopy is commonly used and the implications of using fluoroscopy
as a modality to assess the various radiological indices along with
the effects of using an anteroposterior or posteroanterior fluoroscopic
view are examined. Each of these techniques gives rise to a slightly different
image of the pelvis as the final image is sensitive to the position
of the pelvis and the projection of the x-ray beam. Cite this article:
The orientation of the acetabular component can
influence both the short- and long-term outcomes of total hip replacement
(THR). We performed a prospective, randomised, controlled trial
of two groups, comprising of 40 patients each, in order to compare
freehand introduction of the component with introduction using the transverse
acetabular ligament (TAL) as a reference for anteversion. Anteversion
and inclination were measured on pelvic radiographs. With respect to anteversion, in the freehand group 22.5% of the
components were outside the safe zone With respect to inclination, in the freehand group 37.5% of the
components were outside the safe zone The transverse acetabular ligament may be used to obtain the
appropriate anteversion when introducing the acetabular component
during THR, but not acetabular component inclination. Cite this article:
Failed internal fixation of a fracture of the
proximal humerus produces many challenges with limited surgical options.
The aim of this study was to evaluate the clinical outcomes after
the use of a reverse shoulder arthroplasty under these circumstances.
Between 2007 and 2012, 19 patients (15 women and four men, mean
age 66 years; 52 to 82) with failed internal fixation after a proximal
humeral fracture, underwent implant removal and reverse shoulder arthroplasty
(RSA). The mean follow-up was 36 months (25 to 60). The mean American
Shoulder and Elbow Score improved from 27.8 to 50.1 (p = 0.019).
The mean Simple Shoulder Test score improved from 0.7 to 3.2 (p
= 0.020), and the mean visual analogue scale for pain improved from
6.8 to 4.3 (p = 0.012). Mean forward flexion improved from 58.7°
to 101.1° (p <
0.001), mean abduction from 58.7° to 89.1° (p
= 0.012), mean external rotation from 10.7° to 23.1° (p = 0.043)
and mean internal rotation from buttocks to L4 (p = 0.034). A major
complication was recorded in five patients (26%) (one intra-operative
fracture, loosening of the humeral component in two and two peri-prosthetic
fractures). A total of 15 patients (79%) rated their outcome as
excellent or good, one (5%) as satisfactory, and three (16%) as
unsatisfactory. An improvement in outcomes and pain can be expected when performing
a RSA as a salvage procedure after failed internal fixation of a
fracture of the proximal humerus. Patients should be cautioned about
the possibility for major complications following this technically
demanding procedure. Cite this article:
The outcome of high tibial osteotomy (HTO) deteriorates
with time, and additional procedures may be required. The aim of
this study was to compare the clinical and radiological outcomes
between unicompartmental knee replacement (UKR) and total knee replacement
(TKR) after HTO as well as after primary UKR. A total of 63 patients (63
knees) were studied retrospectively and divided into three groups:
UKR after HTO (group A; n = 22), TKR after HTO (group B; n = 18)
and primary UKR (group C; n = 22). The Oxford knee score (OKS),
Knee Society score (KSS), hip–knee–ankle angles, mechanical axis
and patellar height were evaluated pre- and post-operatively. At
a mean of 64 months (19 to 180) post-operatively the mean OKS was
43.8 (33 to 49), 43.3 (30 to 48) and 42.5 (29 to 48) for groups
A, B and C, respectively (p = 0.73). The mean KSS knee score was
88.8 (54 to 100), 88.11 (51 to 100) and 85.3 (45 to 100) for groups
A, B and C, respectively (p = 0.65), and the mean KSS function score
was 85.0 (50 to 100) in group A, 85.8 (20 to 100) in group B and
79.3 (50 to 100) in group C (p = 0.48). Radiologically the results
were comparable for all groups except for patellar height, with
a higher incidence of patella infra following a previous HTO (p
= 0.02). Cite this article:
The aim of this study was to examine the loading
of the other joints of the lower limb in patients with unilateral osteoarthritis
(OA) of the knee. We recruited 20 patients with no other symptoms
or deformity in the lower limbs from a consecutive cohort of patients
awaiting knee replacement. Gait analysis and electromyographic recordings were
performed to determine moments at both knees and hips, and contraction
patterns in the medial and lateral quadriceps and hamstrings bilaterally.
The speed of gait was reduced in the group with OA compared with
the controls, but there were only minor differences in stance times
between the limbs. Patients with OA of the knee had significant
increases in adduction moment impulse at both knees and the contralateral
hip (adjusted p-values: affected knee: p <
0.01, unaffected knee
p = 0.048, contralateral hip p = 0.03), and significantly increased
muscular co-contraction bilaterally compared with controls (all
comparisons for co-contraction, p <
0.01). The other major weight-bearing joints are at risk from abnormal
biomechanics in patients with unilateral OA of the knee. Cite this article:
The December 2013 Hip &
Pelvis Roundup360 looks at: Enhanced recovery works; Acetabular placement; Exercise better than rest in osteoarthritis patients; if Birmingham hip resurfacing is immune from pseudotumour; HIV and arthroplasty; Labral tears revisited; Prophylactic surgery for FAI; and Ceramics and impaction grafting
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 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:
As many as 25% to 40% of unicompartmental knee
replacement (UKR) revisions are performed for pain, a possible cause
of which is proximal tibial strain. The aim of this study was to
examine the effect of UKR implant design and material on cortical
and cancellous proximal tibial strain in a synthetic bone model.
Composite Sawbone tibiae were implanted with cemented UKR components
of different designs, either all-polyethylene or metal-backed. The tibiae
were subsequently loaded in 500 N increments to 2500 N, unloading
between increments. Cortical surface strain was measured using a
digital image correlation technique. Cancellous damage was measured
using acoustic emission, an engineering technique that detects sonic
waves (‘hits’) produced when damage occurs in material. Anteromedial cortical surface strain showed significant differences
between implants at 1500 N and 2500 N in the proximal 10 mm only
(p <
0.001), with relative strain shielding in metal-backed implants.
Acoustic emission showed significant differences in cancellous bone
damage between implants at all loads (p = 0.001). All-polyethylene implants
displayed 16.6 times the total number of cumulative acoustic emission
hits as controls. All-polyethylene implants also displayed more
hits than controls at all loads (p <
0.001), more than metal-backed
implants at loads ≥ 1500 N (p <
0.001), and greater acoustic
emission activity on unloading than controls (p = 0.01), reflecting
a lack of implant stiffness. All-polyethylene implants were associated
with a significant increase in damage at the microscopic level compared
with metal-backed implants, even at low loads. All-polyethylene
implants should be used with caution in patients who are likely
to impose large loads across their knee joint. Cite this article:
The April 2013 Knee Roundup360 looks at: graft tension and outcome; chondrocytes at the midterm; pre-operative deformity and failure; the designer effect; whether chondroitin sulphate really does work; whether ACL reconstruction is really required; analgesia after TKR; and degenerative meniscus.
We studied the bone mineral density (BMD) and
the bone mineral content (BMC) of the proximal tibia in patients with
a well-functioning uncemented Oxford medial compartment arthroplasty
using the Lunar iDXA bone densitometer. Our hypothesis was that
there would be decreased BMD and BMC adjacent to the tibial base
plate and increased BMD and BMC at the tip of the keel. There were 79 consecutive patients (33 men, 46 women) with a
mean age of 65 years (44 to 84) with a minimum two-year follow-up
(mean 2.6 years (2.0 to 5.0)) after unilateral arthroplasty, who
were scanned using a validated standard protocol where seven regions
of interest (ROI) were examined and compared with the contralateral
normal knee. All had well-functioning knees with a mean Oxford knee
score of 43 (14 to 48) and mean Knee Society function score of 90
(20 to 100), showing a correlation with the increasing scores and
higher BMC and BMD values in ROI 2 in the non-implanted knee relative
to the implanted knee (p = 0.013 and p = 0.015, respectively). The absolute and percentage changes in BMD and BMC were decreased
in all ROIs in the implanted knee compared with the non-implanted
knee, but this did not reach statistical significance. Bone loss
was markedly less than reported losses with total knee replacement. There was no significant association with side, although there
was a tendency for the BMC to decrease with age in men. The BMC
was less in the implanted side relative to the non-implanted side
in men compared with women in ROI 2 (p = 0.027), ROI 3 (p = 0.049)
and ROI 4 (p = 0.029). The uncemented Oxford medial compartment arthroplasty appears
to allow relative preservation of the BMC and BMD of the proximal
tibia, suggesting that the implant acts more physiologically than
total knee replacement. Peri-prosthetic bone loss is an important
factor in assessing long-term implant stability and survival, and
the results of this study are encouraging for the long-term outcome
of this arthroplasty. Cite this article:
The June 2014 Trauma Roundup360 looks at: BMP use increasing wound complication rates in trauma surgery; can we predict re-admission in trauma?; humeral bundle nailing; how best to treat high-angle femoral neck fractures?; hyperglycaemia and infection; simultaneous soft-tissue and bony repair in terrible triad injuries; metaphyseal malunion in the forearm leading to function restrictions; delayed fixation of the distal radius: not a bad option; and fasciotomies better with shoelaces
Ankle replacements have improved significantly since the first reported attempt at resurfacing of the talar dome in 1962. We are now at a stage where ankle replacement offers a viable option in the treatment of end-stage ankle arthritis. As the procedure becomes more successful, it is important to reflect and review the current surgical outcomes. This allows us to guide our patients in the treatment of end-stage ankle arthritis. What is the better surgical treatment – arthrodesis or replacement?