The aim of this study was to find anatomical
landmarks for rotational alignment of the tibial component in total knee
replacement (TKR) in a CT-based study. Pre-operative CT scanning
was performed on 94 South Korean patients (nine men, 85 women, 188
knees) with osteoarthritis of the knee joint prior to TKR. The tibial
anteroposterior (AP) axis was defined as a line perpendicular to
the femoral surgical transepicondylar axis and passing through the centre
of the posterior cruciate ligament (PCL). The angles between the
defined tibial AP axis and anatomical landmarks at various levels
of the tibia were measured. The mean values of the angles between
the defined tibial AP axis and the line connecting the anterior
border of the proximal third of the tibia to the centre of the PCL
was -0.2° (-17 to 14.1, Cite this article:
We describe the clinical and radiological results
of cementless primary total hip replacement (THR) in 25 patients
(18 women and seven men; 30 THRs) with severe developmental dysplasia
of the hip (DDH). Their mean age at surgery was 47 years (23 to
89). In all, 21 hips had Crowe type III dysplasia and nine had Crowe
type IV. Cementless acetabular components with standard polyethylene
liners were introduced as close to the level of the true acetabulum
as possible. The modular cementless S-ROM femoral component was
used with a low resection of the femoral neck. A total of 21 patients (25 THRs) were available for review at
a mean follow-up of 18.7 years (15.8 to 21.8). The mean modified
Harris hip score improved from 46 points pre-operatively to 90 at
final follow up (p <
0.001). A total of 15 patients (17 THRs; 57%) underwent revision of the
acetabular component at a mean of 14.6 years (7 to 20.8), all for
osteolysis. Two patients (two THRs) had symptomatic loosening. No
patient underwent femoral revision. Survival with revision of either
component for any indication was 81% at 15 years (95% CI 60.1 to
92.3), with 21 patients at risk. This technique may reduce the need for femoral osteotomy in severe
DDH, while providing a good long-term functional result. Cite this article:
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 investigated whether shape of the knee
can predict the clinical outcome of patients after an anterior cruciate
ligament rupture. We used statistical shape modelling to measure
the shape of the knee joint of 182 prospectively followed patients
on lateral and Rosenberg view radiographs of the knee after a rupture
of the anterior cruciate ligament. Subsequently, we associated knee
shape with the International Knee Documentation Committee subjective
score at two years follow-up. The mean age of patients was 31 years
(21 to 51), the majority were male (n = 121) and treated operatively
(n = 135). We found two modes (shape variations) that were significantly
associated with the subjective score at two years: one for the operatively
treated group (p = 0.002) and one for the non-operatively treated
group (p = 0.003). Operatively treated patients who had higher subjective
scores had a smaller intercondylar notch and a smaller width of
the intercondylar eminence. Non-operatively treated patients who
scored higher on the subjective score had a more pyramidal intercondylar
notch as opposed to one that was more dome-shaped. We conclude that
the shape of the femoral notch and the intercondylar eminence is predictive
of clinical outcome two years after a rupture of the anterior cruciate
ligament. Cite this article:
The June 2015 Knee Roundup360 looks at: Cruciate substituting
There are many reasons why a total knee replacement
(TKR) may fail and qualify for revision. Successful revision surgery
depends as much on accurate assessment of the problem TKR as it
does on revision implant design and surgical technique. Specific
modes of failure require specific surgical solutions. Causes of
failure are often presented as a list or catalogue, without a system
or process for making a decision. In addition, strict definitions
and consensus on modes of failure are lacking in published series
and registry data. How we approach the problem TKR is an essential
but neglected aspect of understanding knee replacement surgery.
It must be carried out systematically, comprehensively and efficiently.
Eight modes of failure are described: 1) sepsis; 2) extensor discontinuity;
3) stiffness; 4) tibial- femoral instability; 5) patellar tracking;
6) aseptic loosening and osteolysis; 7) periprosthetic fracture
and 8) component breakage. A ninth ‘category’, unexplained pain
is an indication for further investigation but not surgery. Cite this article:
There have been differing descriptions of the
anterolateral structures of the knee, and not all have been named
or described clearly. The aim of this study was to provide a clear
anatomical interpretation of these structures. We dissected 40 fresh-frozen
cadaveric knees to view the relevant anatomy and identified a consistent
structure in 33 knees (83%); we termed this the anterolateral ligament
of the knee. This structure passes antero-distally from an attachment
proximal and posterior to the lateral femoral epicondyle to the
margin of the lateral tibial plateau, approximately midway between
Gerdy’s tubercle and the head of the fibula. The ligament is superficial
to the lateral (fibular) collateral ligament proximally, from which
it is distinct, and separate from the capsule of the knee. In the
eight knees in which it was measured, we observed that the ligament
was isometric from 0° to 60° of flexion of the knee, then slackened
when the knee flexed further to 90° and was lengthened by imposing
tibial internal rotation. Cite this article:
Subtotal or total meniscectomy in the medial or lateral compartment
of the knee results in a high risk of future osteoarthritis. Meniscal
allograft transplantation has been performed for over thirty years
with the scientifically plausible hypothesis that it functions in
a similar way to a native meniscus. It is thought that a meniscal
allograft transplant has a chondroprotective effect, reducing symptoms
and the long-term risk of osteoarthritis. However, this hypothesis has
never been tested in a high-quality study on human participants.
This study aims to address this shortfall by performing a pilot
randomised controlled trial within the context of a comprehensive
cohort study design. Patients will be randomised to receive either meniscal transplant
or a non-operative, personalised knee therapy program. MRIs will
be performed every four months for one year. The primary endpoint
is the mean change in cartilage volume in the weight-bearing area
of the knee at one year post intervention. Secondary outcome measures
include the mean change in cartilage thickness, T2 maps, patient-reported
outcome measures, health economics assessment and complications.Objectives
Methods
There remains conflicting evidence regarding cortical bone strength
following bisphosphonate therapy. As part of a study to assess the
effects of bisphosphonate treatment on the healing of rat tibial
fractures, the mechanical properties and radiological density of
the uninjured contralateral tibia was assessed. Skeletally mature aged rats were used. A total of 14 rats received
1µg/kg ibandronate (iban) daily and 17 rats received 1 ml 0.9% sodium
chloride (control) daily. Stress at failure and toughness of the
tibial diaphysis were calculated following four-point bending tests.Objectives
Methods
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:
Knee arthrodesis is a potential salvage procedure
for limb preservation after failure of total knee arthroplasty (TKA) due
to infection. In this study, we evaluated the outcome of single-stage
knee arthrodesis using an intramedullary cemented coupled nail without
bone-on-bone fusion after failed and infected TKA with extensor
mechanism deficiency. Between 2002 and 2012, 27 patients (ten female,
17 male; mean age 68.8 years; 52 to 87) were treated with septic
single-stage exchange. Mean follow-up duration was 67.1months (24
to 143, n = 27) (minimum follow-up 24 months) and for patients with
a minimum follow-up of five years 104.9 (65 to 143,; n = 13). A
subjective patient evaluation (Short Form (SF)-36) was obtained,
in addition to the Visual Analogue Scale (VAS). The mean VAS score was
1.44 (SD 1.48). At final follow-up, four patients had recurrent
infections after arthrodesis (14.8%). Of these, three patients were
treated with a one-stage arthrodesis nail exchange; one of the three
patients had an aseptic loosening with a third single-stage exchange,
and one patient underwent knee amputation for uncontrolled sepsis at
108 months. All patients, including the amputee, indicated that
they would choose arthrodesis again. Data indicate that a single-stage
knee arthrodesis offers an acceptable salvage procedure after failed
and infected TKA. Cite this article:
The treatment of infected nonunions is difficult.
Antibiotic cement-coated (ACC) rods provide stability as well as delivering
antibiotics. We conducted a review of 110 infected nonunions treated
with ACC rods. Patients were divided into two groups: group A (67
patients) with an infected arthrodesis, and group B (43 patients)
with an infected nonunion in a long bone. In group A, infected arthrodesis,
the success rate after the first procedure was 38/67 (57%), 29/67
(43%) required further surgery for either control of infection or
non-union. At last follow-up, five patients required amputation,
representing a limb salvage rate of 62/67 (93%) overall. In all,
29/67 (43%) presented with a bone defect with a mean size of 6.78
cm (2 to 25). Of those with a bone defect, 13/29 (45%) required
further surgery and had a mean size of defect of 7.2 cm (3.5 to
25). The cultures were negative in 17/67 (26%) and the most common
organism cultured was methicillin-resistant Cite this article:
Hip arthrodesis remains a viable surgical technique
in well selected patients, typically the young manual labourer with
isolated unilateral hip disease. Despite this, its popularity with
patients and surgeons has decreased due to the evolution of hip
replacement, and is seldom chosen by young adult patients today.
The surgeon is more likely to encounter a patient who requests conversion
to total hip replacement (THR). The most common indications are
a painful pseudarthrosis, back pain, ipsilateral knee pain or contralateral
hip pain. Occasionally the patient will request conversion because
of difficulty with activities of daily living, body image and perceived
cosmesis. The technique of conversion and a discussion of the results
are presented. Cite this article:
Only limited data are available regarding the
infiltration of local anaesthetic for total hip arthroplasty (THA),
and no studies were performed for THA using the anterior approach. In this prospective, randomised placebo-controlled study we investigated
the effect of both standard and reverse infiltration of local anaesthetic
in combination with the anterior approach for THA. The primary endpoint
was the mean numeric rating score for pain four hours post-operatively.
In addition, we recorded the length of hospital stay, the operating
time, the destination of the patient at discharge, the use of pain
medication, the occurrence of side effects and pain scores at various
times post-operatively. Between November 2012 and January 2014, 75 patients were included
in the study. They were randomised into three groups: standard infiltration
of local anaesthetic, reversed infiltration of local anaesthetic,
and placebo. There was no difference in mean numeric rating score
for pain four hours post-operatively (p = 0.87). There were significantly
more side effects at one and eight hours post-operatively in the
placebo group (p = 0.02; p = 0.03), but this did not influence the
mobilisation of the patients. There were no differences in all other
outcomes between the groups. We found no clinically relevant effect when the infiltration
of local anaesthetic with ropivacaine and epinephrine was used in
a multimodal pain protocol for THA using the anterior approach. Cite this article:
Construction of a functional skeleton is accomplished
through co-ordination of the developmental processes of chondrogenesis,
osteogenesis, and synovial joint formation. Infants whose movement Cite this article:
The aim of this study was to investigate the
incidence of dysplasia in the ‘normal’ contralateral hip in patients
with unilateral developmental dislocation of the hip (DDH) and to
evaluate the long-term prognosis of such hips. A total of 48 patients
(40 girls and eight boys) were treated for late-detected unilateral
DDH between 1958 and 1962. After preliminary skin traction, closed
reduction was achieved at a mean age of 17.8 months (4 to 65) in
all except one patient who needed open reduction. In 25 patients
early derotation femoral osteotomy of the contralateral hip had been
undertaken within three years of reduction, and later surgery in
ten patients. Radiographs taken during childhood and adulthood were
reviewed. The mean age of the patients was 50.9 years (43 to 55)
at the time of the latest radiological review. In all, eight patients (17%) developed dysplasia of the contralateral
hip, defined as a centre-edge (CE) angle <
20° during childhood
or at skeletal maturity. Six of these patients underwent surgery
to improve cover of the femoral head; the dysplasia improved in
two after varus femoral osteotomy and in two after an acetabular
shelf operation. During long-term follow-up the dysplasia deteriorated
to subluxation in two patients (CE angles 4° and 5°, respectively)
who both developed osteoarthritis (OA), and one of these underwent
total hip replacement at the age of 49 years. In conclusion, the long-term prognosis for the contralateral
hip was relatively good, as OA occurred in only two hips (4%) at
a mean follow-up of 50 years. Regular review of the ‘normal’ side
is indicated, and corrective surgery should be undertaken in those
who develop subluxation. Cite this article:
The piriformis muscle is an important landmark
in the surgical anatomy of the hip, particularly the posterior approach
for total hip replacement (THR). Standard orthopaedic teaching dictates
that the tendon must be cut in to allow adequate access to the superior
part of the acetabulum and the femoral medullary canal. However,
in our experience a routine THR can be performed through a posterior
approach without sacrificing this tendon. We dissected the proximal femora of 15 cadavers in order to clarify
the morphological anatomy of the piriformis tendon. We confirmed
that the tendon attaches on the crest of the greater trochanter,
in a position superior to the trochanteric fossa, away from the
entry point for broaching the intramedullary canal during THR. The
tendon attachment site encompassed the summit and medial aspect
of the greater trochanter as well as a variable attachment to the
fibrous capsule of the hip joint. In addition we dissected seven
cadavers resecting all posterior attachments except the piriformis
muscle and tendon in order to study their relations to the hip joint,
as the joint was flexed. At flexion of 90° the piriformis muscle
lay directly posterior to the hip joint. The piriform fossa is a term used by orthopaedic surgeons to
refer the trochanteric fossa and normally has no relation to the
attachment site of the piriformis tendon. In hip flexion the piriformis
lies directly behind the hip joint and might reasonably be considered
to contribute to the stability of the joint. We conclude that the anatomy of the piriformis muscle is often
inaccurately described in the current surgical literature and terms
are used and interchanged inappropriately. Cite this article:
Concerns have been raised that deformation of
acetabular shells may disrupt the assembly process of modular prostheses.
In this study we aimed to examine the effect that the strength of
bone has on the amount of deformation of the acetabular shell. The
hypothesis was that stronger bone would result in greater deformation.
A total of 17 acetabular shells were inserted into the acetabula
of eight cadavers, and deformation was measured using an optical
measuring system. Cores of bone from the femoral head were taken
from each cadaver and compressed using a materials testing machine.
The highest peak modulus and yield stress for each cadaver were used
to represent the strength of the bone and compared with the values
for the deformation and the surgeon’s subjective assessment of the
hardness of the bone. The mean deformation of the shell was 129
µm (3 to 340). No correlation was found between deformation and
either the maximum peak modulus (r² = 0.011, t = 0.426, p = 0.676) or
the yield stress (r² = 0.024, t = 0.614, p = 0.549) of the bone.
Although no correlation was found between the strength of the bone
and deformation, the values for the deformation observed could be
sufficient to disrupt the assembly process of modular acetabular
components. Cite this article:
One commonly used rat fracture model for bone and mineral research
is a closed mid-shaft femur fracture as described by Bonnarens in
1984. Initially, this model was believed to create very reproducible
fractures. However, there have been frequent reports of comminution
and varying rates of complication. Given the importance of precise
anticipation of those characteristics in laboratory research, we
aimed to precisely estimate the rate of comminution, its importance and
its effect on the amount of soft callus created. Furthermore, we
aimed to precisely report the rate of complications such as death
and infection. We tested a rat model of femoral fracture on 84 rats based on
Bonnarens’ original description. We used a proximal approach with
trochanterotomy to insert the pin, a drop tower to create the fracture
and a high-resolution fluoroscopic imager to detect the comminution.
We weighed the soft callus on day seven and compared the soft callus
parameters with the comminution status.Objectives
Methods
The repair of chondral lesions associated with
femoroacetabular impingement requires specific treatment in addition
to that of the impingement. In this single-centre retrospective
analysis of a consecutive series of patients we compared treatment
with microfracture (MFx) with a technique of enhanced microfracture
autologous matrix-induced chondrogenesis (AMIC). Acetabular grade III and IV chondral lesions measuring between
2 cm2 and 8 cm2 in 147 patients were treated
by MFx in 77 and AMIC in 70. The outcome was assessed using the
modified Harris hip score at six months and one, two, three, four
and five years post-operatively. The outcome in both groups was
significantly improved at six months and one year post-operatively.
During the subsequent four years the outcome in the MFx group slowly deteriorated,
whereas that in the AMIC group remained stable. Six patients in
the MFx group subsequently required total hip arthroplasty, compared
with none in the AMIC group We conclude that the short-term clinical outcome improves in
patients with acetabular chondral damage following both MFx and
AMIC. However, the AMIC group had better and more durable improvement,
particularly in patients with large (≥ 4 cm2) lesions. Cite this article: