Postoperative range of movement (ROM) is an important measure of successful and satisfying total knee arthroplasty (TKA). Reduced postoperative ROM may be evident in up to 20% of all TKAs and negatively affects satisfaction. To improve ROM, manipulation under anaesthesia (MUA) may be performed. Historically, a limited ROM preoperatively was used as the key harbinger of the postoperative ROM. However, comorbidities may also be useful in predicting postoperative stiffness. The goal was to assess preoperative comorbidities in patients undergoing TKA relative to incidence of postoperative MUA. The hope is to forecast those who may be at increased risk and determine if MUA is an effective form of treatment. Prospectively collected data of TKAs performed at our institution’s two hospitals from August 2014 to August 2018 were evaluated for incidence of MUA. Comorbid conditions, risk factors, implant component design and fixation method (cemented vs cementless), and discharge disposition were analyzed. Overall, 3,556 TKAs met the inclusion criteria. Of those, 164 underwent MUA.Aims
Methods
The aims of this study were to compare the efficacy of two agents,
aspirin and warfarin, for the prevention of venous thromboembolism
(VTE) after simultaneous bilateral total knee arthroplasty (SBTKA),
and to elucidate the risk of VTE conferred by this procedure compared
with unilateral TKA (UTKA). A retrospective, multi-institutional study was conducted on 18
951 patients, 3685 who underwent SBTKA and 15 266 who underwent
UTKA, using aspirin or warfarin as VTE prophylaxis. Each patient
was assigned an individualised baseline VTE risk score based on
a system using the Nationwide Inpatient Sample. Symptomatic VTE,
including pulmonary embolism (PE) and deep vein thrombosis (DVT),
were identified in the first 90 days post-operatively. Statistical
analyses were performed with logistic regression accounting for
baseline VTE risk.Aims
Patients and Methods
Patient-specific (PS) implantation surgical technology has been introduced in recent years and a gradual increase in the associated number of surgical cases has been observed. PS technology uses a patient’s own geometry in designing a medical device to provide minimal bone resection with improvement in the prosthetic bone coverage. However, whether PS unicompartmental knee arthroplasty (UKA) provides a better biomechanical effect than standard off-the-shelf prostheses for UKA has not yet been determined, and still remains controversial in both biomechanical and clinical fields. Therefore, the aim of this study was to compare the biomechanical effect between PS and standard off-the-shelf prostheses for UKA. The contact stresses on the polyethylene (PE) insert, articular cartilage and lateral meniscus were evaluated in PS and standard off-the-shelf prostheses for UKA using a validated finite element model. Gait cycle loading was applied to evaluate the biomechanical effect in the PS and standard UKAs.Objectives
Methods
The purpose of this study was to evaluate trends in opioid use
after unicompartmental knee arthroplasty (UKA), to identify predictors
of prolonged use and to compare the rates of opioid use after UKA,
total knee arthroplasty (TKA) and total hip arthroplasty (THA). We identified 4205 patients who had undergone UKA between 2007
and 2015 from the Humana Inc. administrative claims database. Post-operative
opioid use for one year post-operatively was assessed using the
rates of monthly repeat prescription. These were then compared between
patients with and without a specific variable of interest and with
those of patients who had undergone TKA and THA.Aims
Materials and Methods
Aims. Hydroxyapatite coatings for uncemented fixation in total knee
arthroplasty can theoretically provide a long-lasting biological
interface with the host bone. The objective of this study was to
test this hypothesis with propriety hydroxyapatite, peri-apatite,
coated tibial components using component migration measured with radiostereometric
analysis over two years as an indicator of long-term fixation. Patients and Methods. A total of 29 patients at two centres received uncemented PA-coated
tibial components and were followed for two years with radiostereometric
analysis exams to quantify the migration of the component. Results. While there was significant variation in individual migration
patterns, the overall migration of the tibial component in the study
group demonstrated a pattern of initial migration followed by stabilisation
after one year, with mean maximum total point motion (MTPM) of 0.02
mm (standard deviation (. sd. ) 0.20) between one and two years
post-operatively. The direction of greatest motion was subsidence,
which stabilised at three months post-operatively (mean translation
of 0.21 mm, . sd. 0.40). Conclusion. The tibial component migration pattern of stabilisation in the
second
The optimal method of tibial component fixation remains uncertain
in total knee arthroplasty (TKA). Hydroxyapatite coatings have been
applied to improve bone ingrowth in uncemented designs, but may
only coat the directly accessible surface. As peri-apatite (PA)
is solution deposited, this may increase the coverage of the implant
surface and thereby fixation. We assessed the tibial component fixation
of uncemented PA-coated TKAs Patients were randomised to PA-coated or cemented TKAs. In 60
patients (30 in each group), radiostereometric analysis of tibial
component migration was evaluated as the primary outcome at baseline,
three months post-operatively and at one, two and five years. A
linear mixed-effects model was used to analyse the repeated measurements.Aims
Patients and Methods
Patients with flexion instability after total knee arthroplasty
(TKA) often present with a recurrent effusion, which may be a haemarthrosis.
While the radiographic factors contributing to flexion instability
have been elucidated, the clinical diagnosis remains challenging.
Our aim, in this study, was to determine the mean white cell count
and differential profile in pre-operative aspirations of synovial
fluid in a consecutive series of patients undergoing revision TKA
for flexion instability. Between 2000 and 2010, 60 patients undergoing aseptic revision
TKA for flexion instability were identified. The results of the
pre-operative aspiration of synovial fluid were available for 53
patients (88%). These patients were 1:2 matched to 106 patients
who underwent aseptic TKA for indications other than flexion instability.
The mean age of the patients at revision TKA was 65 years (44 to
82) and 55% were women. The mean follow-up was 4.3 years (2 to 10.2).Aims
Patients and Methods
Aims. Little is known about the relative outcomes of revision of unicompartmental
knee arthroplasty (UKA) and high tibial osteotomy (HTO) to total
knee arthroplasty (TKA). The aim of this study is to compare the
outcomes of revision surgery for the two procedures in terms of
complications, re-revision and patient-reported outcome measures (PROMs)
at a minimum of two years follow-up. Patients and Methods. This study was a retrospective review of data from an institutional
arthroplasty registry for cases performed between 2001 and 2014.
A total of 292 patients were identified, of which 217 had a revision
of HTO to TKA, and 75 had revision of UKA to TKA. While mean follow-up
was longer for the HTO group compared with the UKA group, patient
demographics (age, body mass index and Charlson co-morbidity index)
and PROMs (Short Form-36, Oxford Knee Score, Knee Society Score,
both objective and functional) were similar in the two groups prior
to revision surgery. Outcomes included the rate of complications
and
re-operation, PROMS and patient-reported satisfaction at six months
and two years post-operatively. We also compared the duration of
surgery and the need for revision implants in the two groups. . Results . At two-year follow-up, both groups of patients had made significant
improvement in terms of PROMs compared with pre-operative scores.
PROMs and satisfaction rates were similar in the two groups. Complications
requiring re-operation were significantly more frequent in the HTO
group whilst more revision implants were used in the UKA group,
resulting in a longer operative duration. . Conclusion. Revision of HTO and UKA achieve similar
Aims. 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. Patients and Methods. 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
Open wedge high tibial osteotomy (OWHTO) for medial-compartment
osteoarthritis of the knee can be complicated by intra-operative
lateral hinge fracture (LHF). We aimed to establish the relationship
between hinge position and fracture types, and suggest an appropriate
hinge position to reduce the risk of this complication. Consecutive patients undergoing OWHTO were evaluated on coronal
multiplanar reconstruction CT images. Hinge positions were divided
into five zones in our new classification, by their relationship
to the proximal tibiofibular joint (PTFJ). Fractures were classified
into types I, II, and III according to the Takeuchi classification.Aims
Patients and Methods
Objectives. The length of the tourniquet time during total knee arthroplasty (TKA) is related to the incidence of
Aims. The aim of this prospective randomised study was to compare the
time course of clinical improvement during the first two years following
a closing or opening wedge high tibial osteotomy (HTO). It was hypothesised
that there would be no differences in clinical outcome between the
two techniques. Patients and Methods. Between 2007 and 2013, 70 consecutive patients were randomly
allocated to undergo either a closing or opening wedge HTO. All
patients had medial compartment osteoarthritis (OA), and were aged
between 30 years and 60 years. They were evaluated by independent
investigators pre-operatively and at three and six months, and one
and two years post-operatively using the Knee Injury and Osteoarthritis
Outcome Score (KOOS), the Oxford Knee Score (OKS), the Lysholm score,
the Tegner activity score, the University of California, Los Angeles
(UCLA) activity scale and range of movement (ROM). Results. There were no significant differences at any time between the
two techniques for any clinical outcome score (p >
0.05). The mean
scores for all the systems, except UCLA and Tegner, significantly
improved until six months post-operatively (p <
0.001). For some
scores, the improvement continued until one and two years. Conclusion. This prospective randomised study suggests that there are no
differences in the time course of the clinical improvement between
the closing and opening wedge techniques for HTO during the first
two
Patellofemoral arthroplasty (PFA) has experienced significant
improvements in implant survivorship with second generation designs.
This has renewed interest in PFA as an alternative to total knee
arthroplasty (TKA) for younger active patients with isolated patellofemoral
osteoarthritis (PF OA). We analysed the cost-effectiveness of PFA We used a Markov transition state model to compare cost-effectiveness
between PFA and TKA. Simulated patients were aged 60 (base case)
and 50 years. Lifetime costs (2015 United States dollars), quality-adjusted
life year (QALY) gains and incremental cost-effectiveness ratio
(ICER) were calculated from a healthcare payer perspective. Annual rates
of revision were derived from the National Joint Registry for England,
Wales, Northern Ireland and the Isle of Man. Deterministic and probabilistic
sensitivity analysis was performed for all parameters against a
$50 000/QALY willingness to pay. Aims
Patients and Methods
Aims. Little is known about employment following total knee arthroplasty
(TKA). This study aims to identify factors which predict return
to work following TKA in patients of working age in the United Kingdom. Patients &
Methods. We prospectively assessed 289 patients (289 TKAs) aged ≤ 65 years
who underwent TKA between 2010 and 2013. There were 148 women. The
following were recorded pre-operatively: age, gender, body mass
index, social deprivation, comorbidities, indication for surgery,
work status and nature of employment, activity level as assessed by
the University of California, Los Angeles (UCLA) activity score
and Oxford Knee Score (OKS). The intention of patients to return
to work or to retire was not assessed pre-operatively. At a mean
of 3.4 years (2 to 4) post-operatively, the return to work status,
OKS, the EuroQol-5 dimensions (EQ-5D) score, UCLA activity score
and Work, Osteoarthritis and joint-Replacement (WORQ) score were
obtained. Univariate and multivariate analyses were performed. Results. Of 261 patients (90%) who were working before TKA, 105 (40%)
returned to any job, including 89 (34%) who returned to the same
job at a mean of 13.5 weeks (2 to 104) post-operatively. A total
of 108 (41%) retired following TKA and 18 remained on welfare. Patients
not working before the operation did not return to work. Median
UCLA scores improved in 125 patients (58%) from 4 (mild activity)
to 6 (moderate activity) (p <
0.001). Significant
(p <
0.05) factors which were predictive of return to any work
included age, heavy or moderate manual work, better post-operative
UCLA, OKS and EQ-5D general health scores. Significant predictive
factors of return to the same work included age, heavy or moderate
manual work and
The aim of this study was to evaluate the effects of using a
portable, accelerometer-based surgical navigation system (KneeAlign2)
in total knee arthroplasty (TKA) on the alignment of the femoral
component, and blood loss. A total of 241 consecutive patients with primary osteoarthritis
of the knee were enrolled in this prospective, randomised controlled
study. There were 207 women and 34 men. The mean age of the patients
was 74.0 years (57 to 89). The KneeAlign2 system was used for distal
femoral resection in 121 patients (KA2 group) and a conventional intramedullary
femoral guide was used in 120 patients (IM group).Aims
Patients and Methods
Aims. Different methods of anterior cruciate ligament (ACL) reconstruction
have been described for skeletally immature patients before closure
of the growth plates. However, the outcome and complications following
this treatment remain unclear. The aim of this systematic review
was to analyse the outcome and complications of different techniques
which may be used for reconstruction of the ACL in these patients. Materials and Methods. We performed a systematic review of the literature according
to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses
guidelines. This involved a comprehensive search of PubMed, Medline,
CINAHL, Cochrane, Embase and Google Scholar databases using the
following combinations of keywords, “knee”, “anterior cruciate ligament”,
“reconstruction”, “injury”, “children”, “adolescent”, “skeletally
immature”, “open physis” and “surgery”. Results. A total of 53 studies met the inclusion criteria and were included
for analysis. The overall rate of disturbance of growth after ACL
reconstruction was 2.6%, with no statistical difference between
transphyseal and physeal-sparing techniques. Physeal-sparing techniques
had a lower rate of
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
Aims. The aim of this study was to compare the effectiveness of a femoral
nerve block and a periarticular infiltration in the management of
early
The aim of this study was to compare the outcome of revision
total knee arthroplasty (TKA) with and without proximalisation of
the tibial tubercle in patients with a failed primary TKA who have
pseudo patella baja. All revision TKAs, performed between January 2008 and November
2013 at a tertiary referral University Orthopaedic Department were
retrospectively reviewed. Pseudo patella baja was defined using
the modified Insall-Salvati and the Blackburne-Peel ratios. A proximalisation
of the tibial tubercle was performed in 13 patients with pseudo
patella baja who were matched with a control group of 13 patients
for gender, age, height, weight, body mass index, length of surgery
and Blackburne-Peel ratio. Outcome was assessed two years post-operatively
using the Knee Society Score (KSS).Aims
Patients and Methods
Aims. Our aim was to perform a meta-analysis of the outcomes of revision
anterior cruciate ligament (ACL) reconstruction, comparing the use
of different types of graft. Materials and Methods. A search was performed of Medline and Pubmed using the terms
“Anterior Cruciate Ligament” and “ACL” combined with “revision”,
“re-operation” and “failure”. Only studies that reported the outcome
at a minimum follow-up of two years were included. Two authors reviewed
the papers, and outcomes were subdivided into autograft and allograft. Autograft
was subdivided into hamstring (HS) and bone-patellar tendon-bone
(BPTB). Subjective and objective outcome measures were analysed
and odds ratios with confidence intervals were calculated. Results. A total of 32 studies met the inclusion criteria. Five studies
used HS autografts, eight reported using BPTB autografts, two used
quadriceps tendon autografts and eight used various types. Seven
studies reported using allografts, while the two remaining used
both BPTB autografts and allografts. Overall, 1192 patients with
a mean age of 28.7 years (22.5 to 39) and a mean follow-up of 5.4
years (2.0 to 9.6) were treated with autografts, while 269 patients
with a mean age of 28.4 years (25 to 34.6) and a mean follow-up
of 4.0 years (2.3 to 6.0) were treated with allografts. Regarding
allografts, irradiation with 2.5 mrad was used in two studies while
the graft was not irradiated in the seven remaining studies. Reconstructions
following the use of autografts had better outcomes than those using
allograft with respect to laxity, measured by KT-1000/2000 (MEDmetric
Corporation) and the rates of complications and re-operations. Those
following the use of allografts had better mean Lysholm and Tegner
activity scores compared with autografts. If irradiated allografts
were excluded from the analysis, outcomes no longer differed between
the use of autografts and allografts. Comparing the types of autograft,
all outcomes were similar except for HS grafts which had better
International Knee Documentation Committee scores compared with
BPTB grafts. Conclusion. Autografts had better outcomes than allografts in revision ACL
reconstruction, with lower