A flexed knee gait is common in patients with bilateral spastic
cerebral palsy and occurs with increased age. There is a risk for
the recurrence of a flexed knee gait when treated in childhood,
and the aim of this study was to investigate whether multilevel
procedures might also be undertaken in adulthood. At a mean of 22.9 months (standard deviation 12.9), after single
event multi level surgery, 3D gait analysis was undertaken pre-
and post-operatively for 37 adult patients with bilateral cerebral
palsy and a fixed knee gait.Aims
Patients and Methods
Fractures around total knee arthroplasties pose
a significant surgical challenge. Most can be managed with osteosynthesis
and salvage of the replacement. The techniques of fixation of these
fractures and revision surgery have evolved and so has the assessment
of outcome. This specialty update summarises the current evidence
for the classification, methods of fixation, revision surgery and
outcomes of the management of periprosthetic fractures associated
with total knee arthroplasty. Cite this article:
We aimed to investigate factors related to the technique of medial
opening wedge high tibial osteotomy which might predispose to the
development of a lateral hinge fracture. A total of 71 patients with 82 osteotomies were included in the
study. Their mean age was 62.9 years (37 to 80). The classification
of the type of osteotomy was based on whether it extended beyond
the fibular head. The level of the osteotomy was classified according
to the height of its endpoint.Aims
Patients and Methods
We investigated the effects on fracture healing of two up-regulators of inducible nitric oxide synthase (iNOS) in a rat model of an open femoral osteotomy: tadalafil, a phosphodiesterase inhibitor, and the recently reported nutraceutical, COMB-4 (consisting of L-citrulline, Paullinia cupana, ginger and muira puama), given orally for either 14 or 42 days. Unilateral femoral osteotomies were created in 58 male rats and fixed with an intramedullary compression nail. Rats were treated daily either with vehicle, tadalafil or COMB-4. Biomechanical testing of the healed fracture was performed on day 42. The volume, mineral content and bone density of the callus were measured by quantitative CT on days 14 and 42. Expression of iNOS was measured by immunohistochemistry.Objectives
Materials and Methods
A key to the success of revision total knee arthroplasty
(TKA) is a safe surgical approach using an exposure that minimises
complications. In most patients, a medial parapatellar arthrotomy
with complete synovectomy is sufficient. If additional exposure
is needed, a quadriceps snip performed through the quadriceps tendon
often provides the additional exposure required. It is simple to
perform and does not alter the post-operative rehabilitative protocol.
In rare cases, in which additional exposure is needed, or when removal
of a cemented long-stemmed tibial component is required, a tibial
tubercle osteotomy (TTO) may be used. Given the risk of post-operative
extensor lag, a V-Y quadricepsplasty is rarely indicated and usually
considered only if TTO is not possible. Cite this article:
The aim of this consensus was to develop a definition of post-operative
fibrosis of the knee. An international panel of experts took part in a formal consensus
process composed of a discussion phase and three Delphi rounds.Aims
Patients and Methods
The aim of this study was to analyse the gait
pattern, muscle force and functional outcome of patients who had undergone
replacement of the proximal tibia for tumour and alloplastic reconstruction
of the extensor mechanism using the patellar-loop technique. Between February 1998 and December 2009, we carried out wide
local excision of a primary sarcoma of the proximal tibia, proximal
tibial replacement and reconstruction of the extensor mechanism
using the patellar-loop technique in 18 patients. Of these, nine
were available for evaluation after a mean of 11.6 years (0.5 to
21.6). The strength of the knee extensors was measured using an
Isobex machine and gait analysis was undertaken in our gait assessment
laboratory. Functional outcome was assessed using the American Knee
Society (AKS) and Musculoskeletal Tumor Society (MSTS) scores. The gait pattern of the patients differed in ground contact time,
flexion heel strike, maximal flexion loading response and total
sagittal plane excursion. The mean maximum active flexion was 91°
(30° to 110°). The overall mean extensor lag was 1° (0° to 5°).
The mean extensor muscle strength was 25.8% (8.3% to 90.3%) of that
in the non-operated leg (p <
0.001). The mean functional scores
were 68.7% (43.4% to 83.3%) (MSTS) and 71.1 (30 to 90) (AKS functional
score). In summary, the results show that reconstruction of the extensor
mechanism using this technique gives good biomechanical and functional
results. The patients’ gait pattern is close to normal, except for
a somewhat stiff knee gait pattern. The strength of the extensor
mechanism is reduced, but sufficient for walking. Cite this article:
We investigated changes in the axial alignment of the ipsilateral
hip and knee after total hip arthroplasty (THA). We reviewed 152 patients undergoing primary THA (163 hips; 22
hips in men, 141 hips in women) without a pre-operative flexion
contracture. The mean age was 64 years (30 to 88). The diagnosis
was osteoarthritis (OA) in 151 hips (primary in 18 hips, and secondary
to dysplasia in 133) and non-OA in 12 hips. A posterolateral approach
with repair of the external rotators was used in 134 hips and an
anterior approach in 29 hips. We measured changes in leg length
and offset on radiographs, and femoral anteversion, internal rotation
of the hip and lateral patellar tilt on CT scans, pre- and post-operatively. Aims
Patients and Methods
Valgus knee deformity can present a number of
unique surgical challenges for the total knee arthroplasty (TKA)
surgeon. Understanding the typical patterns of bone and soft-tissue pathology
in the valgus arthritic knee is critical for appropriate surgical
planning. This review aims to provide the knee arthroplasty surgeon
with an understanding of surgical management strategies for the
treatment of valgus knee arthritis. Lateral femoral and tibial deficiencies, contracted lateral soft
tissues, attenuated medial soft tissues, and multiplanar deformities
may all be present in the valgus arthritic knee. A number of classifications
have been reported in order to guide surgical management, and a variety
of surgical strategies have been described with satisfactory clinical
results. Depending on the severity of the deformity, a variety of
TKA implant designs may be appropriate for use. Regardless of an operating surgeon’s preferred surgical strategy,
adherence to a step-wise approach to deformity correction is advised. Cite this article:
The aims of this study were to determine the proportion of patients
with outlier varus or valgus alignment in kinematically aligned
total knee arthroplasty (TKA), whether those with outlier varus
or valgus alignment have higher forces in the medial or lateral
compartments of the knee than those with in-range alignment and
whether measurements of the alignment of the limb, knee and components
predict compartment forces. The intra-operative forces in the medial and lateral compartments
were measured with an instrumented tibial insert in 67 patients
who underwent a kinematically aligned TKA during passive movement.
The mean of the forces at full extension, 45° and 90° of flexion
determined the force in the medial and lateral compartments. Measurements
of the alignment of the limb and the components included the hip-knee-ankle
(HKA) angle, proximal medial tibial angle (PMTA), and distal lateral
femoral angle (DLFA). Measurements of the alignment of the knee
and the components included the tibiofemoral angle (TFA), tibial
component angle (TCA) and femoral component angle (FCA). Alignment was
measured on post-operative, non-weight-bearing anteroposterior (AP)
scanograms and categorised as varus or valgus outlier or in-range
in relation to mechanically aligned criteria.Aims
Patients and Methods
The purpose of this current multicentre study is to analyse the
presence of alpha-defensin proteins in synovial fluid using the
Synovasure lateral flow device and to determine its diagnostic reliability
and accuracy compared with the prosthetic joint infection (PJI)
criteria produced by the Musculoskeletal Infection Society (MSIS). A cohort of 121 patients comprising 85 total knee arthroplasties
and 36 total hip arthroplasties was prospectively evaluated between
May 2015 and June 2016 in three different orthopaedic centres. The
tests were performed on patients with a chronically painful prosthesis
undergoing a joint aspiration in a diagnostic pathway or during revision
surgery.Aims
Patients and Methods
Preservation of both anterior and posterior cruciate ligaments in total knee arthroplasty (TKA) can lead to near-normal post-operative joint mechanics and improved knee function. We hypothesised that a patient-specific bicruciate-retaining prosthesis preserves near-normal kinematics better than standard off-the-shelf posterior cruciate-retaining and bicruciate-retaining prostheses in TKA. We developed the validated models to evaluate the post-operative kinematics in patient-specific bicruciate-retaining, standard off-the-shelf bicruciate-retaining and posterior cruciate-retaining TKA under gait and deep knee bend loading conditions using numerical simulation.Objectives
Methods
Microindentation has the potential to measure the stiffness of an individual patient’s bone. Bone stiffness plays a crucial role in the press-fit stability of orthopaedic implants. Arming surgeons with accurate bone stiffness information may reduce surgical complications including periprosthetic fractures. The question addressed with this systematic review is whether microindentation can accurately measure cortical bone stiffness. A systematic review of all English language articles using a keyword search was undertaken using Medline, Embase, PubMed, Scopus and Cochrane databases. Studies that only used nanoindentation, cancellous bone or animal tissue were excluded.Objectives
Methods
Total knee arthroplasty (TKA) is a cost effective
and extremely successful operation. As longevity increases, the demand
for primary TKA will continue to rise. The success and survivorship
of TKAs are dependent on the demographics of the patient, surgical
technique and implant-related factors. Currently the risk of failure of a TKA requiring revision surgery
ten years post-operatively is 5%. The most common indications for revision include aseptic loosening
(29.8%), infection (14.8%), and pain (9.5%). Revision surgery poses
considerable clinical burdens on patients and financial burdens
on healthcare systems. We present a current concepts review on the epidemiology of failed
TKAs using data from worldwide National Joint Registries. Cite this article:
It is widely held that most Baker’s cysts resolve after treatment
of the intra-articular knee pathology. The present study aimed to
evaluate the fate of Baker’s cysts and their associated symptoms
after total knee arthroplasty (TKA). In this prospective cohort study, 102 patients with (105 were
included, however three were lost to follow-up) an MRI-verified
Baker’s cyst, primary osteoarthritis and scheduled for TKA were
included. Ultrasound was performed to evaluate the existence and
the gross size of the cyst before and at one year after TKA. Additionally,
associated symptoms of Baker's cyst were recorded pre- and post-operatively.Aims
Patients and Methods
An increased tibial tubercle–trochlear groove
(TT-TG) distance is related to patellar maltracking and instability.
Tibial tubercle transfer is a common treatment option for these
patients with good short-term results, although the results can
deteriorate over time owing to the progression of osteoarthritis.
We present a ten-year follow-up study of a self-centring tibial
tubercle osteotomy in 60 knees, 30 with maltracking and 30 with
patellar instability. Inclusion criteria were a TT-TG ≥ 15 mm and
symptoms for >
one year. One patient (one knee) was lost to follow-up
and one required total knee arthroplasty because of progressive
osteoarthritis. Further patellar dislocations occurred in three
knees, all in the instability group, one of which required further
surgery. The mean visual analogue scores for pain, and Lysholm and
Kujala scores improved significantly and were maintained at the
final follow-up (repeated measures, p = 0.000, intergroup differences
p = 0.449). Signs of maltracking were found in only a minority of
patients, with no difference between groups (p >
0.05). An increase
in patellofemoral osteoarthritis was seen in 16 knees (31%) with
a maximum of grade 2 on the Kellgren–Lawrence scale. The mean increase
in grades was 0.31 (0 to 2) and 0.41 (0 to 2) in the maltracking
and instability groups respectively (p = 0.2285) This self-centring tibial tubercle osteotomy provides good results
at ten years’ follow-up without inducing progressive osteoarthritis. Cite this article:
This study reports the clinical outcome of reconstruction
of deficient abductor muscles following revision total hip arthroplasty
(THA), using a fresh–frozen allograft of the extensor mechanism
of the knee. A retrospective analysis was conducted of 11 consecutive
patients with a severe limp because of abductor deficiency which
was confirmed on MRI scans. The mean age of the patients (three
men and eight women) was 66.7 years (52 to 84), with a mean follow-up
of 33 months (24 to 41). Following surgery, two patients had no limp, seven had a mild
limp, and two had a persistent severe limp (p = 0.004). The mean
power of the abductors improved on the Medical Research Council
scale from 2.15 to 3.8 (p <
0.001). Pre-operatively, all patients
required a stick or walking frame; post-operatively, four patients
were able to walk without an aid. Overall, nine patients had severe
or moderate pain pre-operatively; ten patients had no or mild pain
post-operatively. At final review, the Harris hip score was good in five patients,
fair in two and poor in four. We conclude that using an extensor mechanism allograft is relatively
effective in the treatment of chronic abductor deficiency of the
hip after THA when techniques such as local tissue transfer are
not possible. Longer-term follow-up is necessary before the technique can be
broadly applied. Cite this article:
During open orthopaedic surgery, joints may be exposed to air, potentially leading to cartilage drying and chondrocyte death, however, the long-term effects of joint drying The patellar groove of anaesthetised rats was exposed (sham-operated), or exposed and then subjected to laminar airflow (0.25m/s; 60 minutes) before wounds were sutured and animals recovered. Animals were monitored for up to eight weeks and then sacrificed. Cartilage and chondrocyte properties were studied by histology and confocal microscopy, respectively.Objectives
Methods