Aims. A fracture of the medial tibial plateau is a serious complication of Oxford mobile-bearing unicompartmental knee arthroplasty (OUKA). The risk of these fractures is reportedly lower when using components with a longer keel-cortex distance (KCDs). The aim of this study was to examine how slight varus placement of the tibial component might affect the KCDs, and the rate of
Aims. Cementless unicompartmental knee arthroplasty (UKA) has advantages over cemented UKA, including improved fixation, but has a higher risk of
Aims. This study aims to determine the rate of and risk factors for total knee arthroplasty (TKA) after operative management of
Aims. Tibial tubercle osteotomy (TTO) facilitates surgical exposure and protects the extensor mechanism during revision total knee arthroplasty (rTKA). The purpose of this study was to determine the rates of bony union, complications, and reoperations following TTO during rTKA, to assess the functional outcomes of rTKA with TTO at two years’ minimum follow-up, and to identify the risk factors of failure. Methods. Between January 2010 and September 2020, 695 rTKAs were performed and data were entered into a prospective database. Inclusion criteria were rTKAs with concomitant TTO, without extensor mechanism allograft, and a minimum of two years’ follow-up. A total of 135 rTKAs were included, with a mean age of 65 years (SD 9.0) and a mean BMI of 29.8 kg/m. 2. (SD 5.7). The most frequent indications for revision were infection (50%; 68/135), aseptic loosening (25%; 34/135), and stiffness (13%; 18/135). Patients had standardized follow-up at six weeks, three months, six months, and annually thereafter. Complications and revisions were evaluated at the last follow-up. Functional outcomes were assessed using the Knee Society Score (KSS) and range of motion. Results. The mean follow-up was 51 months (SD 26; 24 to 121). Bony union was confirmed in 95% of patients (128/135) at a mean of 3.4 months (SD 2.7). The complication rate was 15% (20/135), consisting of nine
This prospective study reports longitudinal, within-patient, patient-reported outcome measures (PROMs) over a 15-year period following cemented single radius total knee arthroplasty (TKA). Secondary aims included reporting PROMs trajectory, 15-year implant survival, and patient attrition from follow-up. From 2006 to 2007, 462 consecutive cemented cruciate-retaining Triathlon TKAs were implanted in 426 patients (mean age 69 years (21 to 89); 290 (62.7%) female). PROMs (12-item Short Form Survey (SF-12), Oxford Knee Score (OKS), and satisfaction) were assessed preoperatively and at one, five, ten, and 15 years. Kaplan-Meier survival and univariate analysis were performed.Aims
Methods
Knowledge on total knee arthroplasties (TKAs) in patients with a history of poliomyelitis is limited. This study compared implant survivorship and clinical outcomes among affected and unaffected limbs in patients with sequelae of poliomyelitis undergoing TKAs. A retrospective review of our total joint registry identified 94 patients with post-polio syndrome undergoing 116 primary TKAs between January 2000 and December 2019. The mean age was 70 years (33 to 86) with 56% males (n = 65) and a mean BMI of 31 kg/m2 (18 to 49). Rotating hinge TKAs were used in 14 of 63 affected limbs (22%), but not in any of the 53 unaffected limbs. Kaplan-Meier survivorship analyses were completed. The mean follow-up was eight years (2 to 19).Aims
Methods
The tibial component of total knee arthroplasty can either be an all-polyethylene (AP) implant or a metal-backed (MB) implant. This study aims to compare the five-year functional outcomes of AP tibial components to MB components in patients aged over 70 years. Secondary aims are to compare quality of life, implant survivorship, and cost-effectiveness. A group of 130 patients who had received an AP tibial component were matched for demographic factors of age, BMI, American Society of Anesthesiologists (ASA) grade, sex, and preoperative Knee Society Score (KSS) to create a comparison group of 130 patients who received a MB tibial component. Functional outcome was assessed prospectively by KSS, quality of life by 12-Item Short-Form Health Survey questionnaire (SF-12), and range of motion (ROM), and implant survivorships were compared. The SF six-dimension (6D) was used to calculate the incremental cost effectiveness ratio (ICER) for AP compared to MB tibial components using quality-adjusted life year methodology.Aims
Methods
Robotic arm-assisted surgery offers accurate and reproducible guidance in component positioning and assessment of soft-tissue tensioning during knee arthroplasty, but the feasibility and early outcomes when using this technology for revision surgery remain unknown. The objective of this study was to compare the outcomes of robotic arm-assisted revision of unicompartmental knee arthroplasty (UKA) to total knee arthroplasty (TKA) versus primary robotic arm-assisted TKA at short-term follow-up. This prospective study included 16 patients undergoing robotic arm-assisted revision of UKA to TKA versus 35 matched patients receiving robotic arm-assisted primary TKA. In all study patients, the following data were recorded: operating time, polyethylene liner size, change in haemoglobin concentration (g/dl), length of inpatient stay, postoperative complications, and hip-knee-ankle (HKA) alignment. All procedures were performed using the principles of functional alignment. At most recent follow-up, range of motion (ROM), Forgotten Joint Score (FJS), and Oxford Knee Score (OKS) were collected. Mean follow-up time was 21 months (6 to 36).Aims
Methods
The aim of this study was to determine the risk of tibial eminence avulsion intraoperatively for bi-unicondylar knee arthroplasty (Bi-UKA), with consideration of the effect of implant positioning, overstuffing, and sex, compared to the risk for isolated medial unicondylar knee arthroplasty (UKA-M) and bicruciate-retaining total knee arthroplasty (BCR-TKA). Two experimentally validated finite element models of tibia were implanted with UKA-M, Bi-UKA, and BCR-TKA. Intraoperative loads were applied through the condyles, anterior cruciate ligament (ACL), medial collateral ligament (MCL), and lateral collateral ligament (LCL), and the risk of fracture (ROF) was evaluated in the spine as the ratio of the 95th percentile maximum principal elastic strains over the tensile yield strain of proximal tibial bone.Aims
Methods
This systematic review and meta-analysis aimed to compare the influence of patellar resurfacing following cruciate-retaining (CR) and posterior-stabilized (PS) total knee arthroplasty (TKA) on the incidence of anterior knee pain, knee-specific patient-reported outcome measures, complication rates, and reoperation rates. A systematic review of MEDLINE, PubMed, and Google Scholar was performed to identify randomized controlled trials (RCTs) according to search criteria. Search terms used included: arthroplasty, replacement, knee (Mesh), TKA, prosthesis, patella, patellar resurfacing, and patellar retaining. RCTs that compared patellar resurfacing versus unresurfaced in primary TKA were included for further analysis. Studies were evaluated using the Scottish Intercollegiate Guidelines Network assessment tool for quality and minimization of bias. Data were synthesized and meta-analysis performed.Aims
Methods
Unicompartmental knee arthroplasty (UKA) has higher revision rates than total knee arthroplasty (TKA). As revision of UKA may be less technically demanding than revision TKA, UKA patients with poor functional outcomes may be more likely to be offered revision than TKA patients with similar outcomes. The aim of this study was to compare clinical thresholds for revisions between TKA and UKA using revision incidence and patient-reported outcomes, in a large, matched cohort at early, mid-, and late-term follow-up. Analyses were performed on propensity score-matched patient cohorts of TKAs and UKAs (2:1) registered in the New Zealand Joint Registry between 1 January 1999 and 31 December 2019 with an Oxford Knee Score (OKS) response at six months (n, TKA: 16,774; UKA: 8,387), five years (TKA: 6,718; UKA: 3,359), or ten years (TKA: 3,486; UKA: 1,743). Associations between OKS and revision within two years following the score were examined. Thresholds were compared using receiver operating characteristic analysis. Reasons for aseptic revision were compared using cumulative incidence with competing risk.Aims
Methods
Aims. The treatment of patients with allergies to metal in total joint arthroplasty is an ongoing debate. Possibilities include the use of hypoallergenic prostheses, as well as the use of standard cobalt-chromium (CoCr) alloy. This non-designer study was performed to evaluate the clinical outcome and survival rates of unicondylar knee arthroplasty (UKA) using a standard CoCr alloy in patients reporting signs of a hypersensitivity to metal. Patients and Methods. A consecutive series of patients suitable for UKA were screened for symptoms of metal hypersensitivity by use of a questionnaire. A total of 82 patients out of 1737 patients suitable for medial UKA reporting cutaneous metal hypersensitivity to cobalt, chromium, or nickel were included into this study and prospectively evaluated to determine the functional outcome, possible signs of hypersensitivity, and short-term survivorship at a minimum follow-up of 1.5 years. Results. At a mean follow-up of three years (1.5 to 5.7), no local or systemic symptoms of hypersensitivity to metal were observed. One patient underwent revision surgery to a bicondylar prosthesis due to a
The role of arthroscopy in the treatment of soft-tissue
injuries associated with proximal
Tibial cones are often utilized in revision total knee arthroplasty (TKA) with metaphyseal defects. Because there are few studies evaluating mid-term outcomes with a sufficient cohort, the purpose of this study was to evaluate tibial cone survival and complications in revision TKAs with tibial cones at minimum follow-up of five years. A retrospective review was completed from September 2006 to March 2015, evaluating 67 revision TKAs (64 patients) that received one specific porous tibial cone during revision TKA. The final cohort was composed of 62 knees (59 patients) with five years of clinical follow-up or reoperation. The mean clinical follow-up of the TKAs with minimum five-year clinical follow-up was 7.6 years (5.0 to 13.3). Survivorship analysis was performed with the endpoints of tibial cone revision for aseptic loosening, tibial cone revision for any reason, and reoperation. We also evaluated periprosthetic joint infection (PJI), risk factors for failure, and performed a radiological review.Aims
Methods
Joint registries classify all further arthroplasty procedures to a knee with an existing partial arthroplasty as revision surgery, regardless of the actual procedure performed. Relatively minor procedures, including bearing exchanges, are classified in the same way as major operations requiring augments and stems. A new classification system is proposed to acknowledge and describe the detail of these procedures, which has implications for risk, recovery, and health economics. Classification categories were proposed by a surgical consensus group, then ranked by patients, according to perceived invasiveness and implications for recovery. In round one, 26 revision cases were classified by the consensus group. Results were tested for inter-rater reliability. In round two, four additional cases were added for clarity. Round three repeated the survey one month later, subject to inter- and intrarater reliability testing. In round four, five additional expert partial knee arthroplasty surgeons were asked to classify the 30 cases according to the proposed revision partial knee classification (RPKC) system.Aims
Methods
Uncemented mobile bearing designs in medial unicompartmental knee arthroplasty (UKA) have seen an increase over the last decade. However, there are a lack of large-scale studies comparing survivorship of these specific designs to commonly used cemented mobile and fixed bearing designs. The aim of this study was to evaluate the survivorship of these designs. A total of 21,610 medial UKAs from 2007 to 2018 were selected from the Dutch Arthroplasty Register. Multivariate Cox regression analyses were used to compare uncemented mobile bearings with cemented mobile and fixed bearings. Adjustments were made for patient and surgical factors, with their interactions being considered. Reasons and type of revision in the first two years after surgery were assessed.Aims
Methods
An abnormal lateral position of the tibial tuberosity causes distal malalignment of the extensor mechanism of the knee and can lead to lateral tracking of the patella causing anterior knee pain or objective patellar instability, characterised by recurrent dislocation. Computer tomography is used for a precise pre-operative assessment of the tibial tubercle-trochlear groove distance. A distance of more than 15 mm is considered to be pathological and an indication for surgery in symptomatic patients. In a prospective study we performed a subtle transfer of the tibial tuberosity according to the information gained from the pre-operative CT scan. This method was applied to two groups of patients, those with painful lateral tracking of the patella, and those with objective patellar instability. We evaluated the clinical results in 30 patients in each group. The outcome was documented at 3, 12 and 24 months using the Lysholm scale, the Kujala score, and a visual analogue pain score. Post-operatively, all but one patient in the instability group who had a patellar dislocation requiring further surgery reported good improvement with no further subluxation or dislocation. All patients in both groups had a marked improvement in pain and functional score. Two patients sustained a
An algorithm to determine the constitutional alignment of the lower limb once arthritic deformity has occurred would be of value when undertaking kinematically aligned total knee arthroplasty (TKA). The purpose of this study was to determine if the arithmetic hip-knee-ankle angle (aHKA) algorithm could estimate the constitutional alignment of the lower limb following development of significant arthritis. A matched-pairs radiological study was undertaken comparing the aHKA of an osteoarthritic knee (aHKA-OA) with the mechanical HKA of the contralateral normal knee (mHKA-N). Patients with Grade 3 or 4 Kellgren-Lawrence tibiofemoral osteoarthritis in an arthritic knee undergoing TKA and Grade 0 or 1 osteoarthritis in the contralateral normal knee were included. The aHKA algorithm subtracts the lateral distal femoral angle (LDFA) from the medial proximal tibial angle (MPTA) measured on standing long leg radiographs. The primary outcome was the mean of the paired differences in the aHKA-OA and mHKA-N. Secondary outcomes included comparison of sex-based differences and capacity of the aHKA to determine the constitutional alignment based on degree of deformity.Aims
Methods
Varus-valgus constrained (VVC) implants are often used during revision total knee arthroplasty (TKA) to gain coronal plane stability. However, the increased mechanical torque applied to the bone-cement interface theoretically increases the risk of aseptic loosening. We assessed mid-term survivorship, complications, and clinical outcomes of a fixed-bearing VVC device in revision TKAs. A total of 416 consecutive revision TKAs (398 patients) were performed at our institution using a single fixed-bearing VVC TKA from 2007 to 2015. Mean age was 64 years (33 to 88) with 50% male (199). Index revision TKA diagnoses were: instability (n = 122, 29%), aseptic loosening (n = 105, 25%), and prosthetic joint infection (PJI) (n = 97, 23%). All devices were cemented on the epiphyseal surfaces. Femoral stems were used in 97% (n = 402) of cases, tibial stems in 95% (n = 394) of cases; all were cemented. In total, 93% (n = 389) of cases required a stemmed femoral and tibial component. Femoral cones were used in 29%, and tibial cones in 40%. Survivorship was assessed via competing risk analysis; clinical outcomes were determined using Knee Society Scores (KSSs) and range of movement (ROM). Mean follow-up was four years (2 to 10).Aims
Methods
Metaphyseal fixation during revision total knee arthroplasty (TKA) is important, but potentially difficult when using historical designs of cone. Material and manufacturing innovations have improved the size and shape of the cones which are available, and simplified the required bone preparation. In a large series, we assessed the implant survivorship, radiological results, and clinical outcomes of new porous 3D-printed titanium metaphyseal cones featuring a reamer-based system. We reviewed 142 revision TKAs in 139 patients using 202 cones (134 tibial, 68 femoral) which were undertaken between 2015 and 2016. A total of 60 involved tibial and femoral cones. Most cones (149 of 202; 74%) were used for Type 2B or 3 bone loss. The mean age of the patients was 66 years (44 to 88), and 76 (55 %) were female. The mean body mass index (BMI) was 34 kg/m2 (18 to 60). The patients had a mean of 2.4 (1 to 8) previous operations on the knee, and 68 (48%) had a history of prosthetic infection. The mean follow-up was 2.4 years (2 to 3.6).Aims
Methods
Unicompartmental knee arthroplasty (UKA) is one surgical option for treating symptomatic medial osteoarthritis. Clinical studies have shown the functional benefits of UKA; however, the optimal alignment of the tibial component is still debated. The purpose of this study was to evaluate the effects of tibial coronal and sagittal plane alignment in UKA on knee kinematics and cruciate ligament tension, using a musculoskeletal computer simulation. The tibial component was first aligned perpendicular to the mechanical axis of the tibia, with a 7° posterior slope (basic model). Subsequently, coronal and sagittal plane alignments were changed in a simulation programme. Kinematics and cruciate ligament tensions were simulated during weight-bearing deep knee bend and gait motions. Translation was defined as the distance between the most medial and the most lateral femoral positions throughout the cycle.Objectives
Methods
The primary stability of the cementless Oxford Unicompartmental Knee Replacement (OUKR) relies on interference fit (or press fit). Insufficient interference may cause implant loosening, whilst excessive interference could cause bone damage and fracture. The aim of this study was to identify the optimal interference fit by measuring the force required to seat the tibial component of the cementless OUKR (push-in force) and the force required to remove the component (pull-out force). Six cementless OUKR tibial components were implanted in 12 new slots prepared on blocks of solid polyurethane foam (20 pounds per cubic foot (PCF), Sawbones, Malmo, Sweden) with a range of interference of 0.1 mm to 1.9 mm using a Dartec materials testing machine HC10 (Zwick Ltd, Herefordshire, United Kingdom) . The experiment was repeated with cellular polyurethane foam (15 PCF), which is a more porous analogue for trabecular bone.Objectives
Materials 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:
Our aim was to examine the clinical and radiographic outcomes
in 257 consecutive Oxford unicompartmental knee arthroplasties (OUKAs)
(238 patients), five years post-operatively. A retrospective evaluation was undertaken of patients treated
between April 2008 and October 2010 in a regional centre by two
non-designing surgeons with no previous experience of UKAs. The
Oxford Knee Scores (OKSs) were recorded and fluoroscopically aligned
radiographs were assessed post-operatively at one and five years.Aims
Patients and Methods
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
A total of 22 patients with a tibial avulsion
fracture involving the insertion of the posterior cruciate ligament
(PCL) with grade II or III posterior laxity were reduced and fixed
arthroscopically using routine anterior and double posteromedial
portals. A double-strand Ethibond suture was inserted into the joint
and wrapped around the PCL from anterior to posterior to secure
the ligament above the avulsed bony fragment. Two tibial bone tunnels
were created using the PCL reconstruction guide, aiming at the medial
and lateral borders of the tibial bed. The ends of the suture were
pulled out through the bone tunnels and tied over the tibial cortex
between the openings of the tunnels to reduce and secure the bony
fragment. Satisfactory reduction of the fracture was checked arthroscopically and
radiographically. The patients were followed-up for a mean of 24.5 months (19 to
28). Bone union occurred six weeks post-operatively. At final follow-up,
all patients had a negative posterior drawer test and a full range
of movement. KT-1000 arthrometer examination showed that the mean
post-operative side-to-side difference improved from 10.9 mm (standard
deviation ( We conclude that this technique is convenient, reliable and minimally
invasive and successfully restores the stability and function of
the knee. Cite this article:
We have investigated iatrogenic popliteal artery
injuries (PAI) during non arthroplasty knee surgery regarding mechanism
of injury, treatment and outcomes, and to identify successful strategies
when injury occurs. In all, 21 iatrogenic popliteal artery injuries in 21 patients
during knee surgery other than knee arthroplasty were identified
from the Swedish Vascular Registry (Swedvasc) between 1987 and 2011.
Prospective registry data were supplemented with case-records, including
long-term follow-up. In total, 13 patients suffered PAI during elective surgery
and eight during urgent surgery such as fracture fixation or tumour
resection. Nine injuries were detected intra-operatively, five within
12 to 48 hours and seven >
48 hours post-operatively (two days to
23 years). There were 19 open vascular and two endovascular surgical repairs.
Two patients died within six months of surgery. One patient required
amputation. Only six patients had a complete recovery of whom had
the vascular injury detected at time of injury and repaired by a
vascular surgeon. Patients sustaining vascular injury during elective
procedures are more likely to litigate (p = 0.029). We conclude that outcomes are poorer when there is a delay of
diagnosis and treatment, and that orthopaedic surgeons should develop
strategies to detect PAI early and ensure rapid access to vascular
surgical support. Cite this article:
This review considers the surgical treatment
of displaced fractures involving the knee in elderly, osteoporotic patients.
The goals of treatment include pain control, early mobilisation,
avoidance of complications and minimising the need for further surgery.
Open reduction and internal fixation (ORIF) frequently results in
loss of reduction, which can result in post-traumatic arthritis
and the occasional conversion to total knee replacement (TKR). TKR
after failed internal fixation is challenging, with modest functional
outcomes and high complication rates. TKR undertaken as treatment
of the initial fracture has better results to late TKR, but does
not match the outcome of primary TKR without complications. Given
the relatively infrequent need for late TKR following failed fixation,
ORIF is the preferred management for most cases. Early TKR can be
considered for those patients with pre-existing arthritis, bicondylar
femoral fractures, those who would be unable to comply with weight-bearing restrictions,
or where a single definitive procedure is required.
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 Cementless Oxford Unicompartmental Knee Replacement
(OUKR) was developed to address problems related to cementation,
and has been demonstrated in a randomised study to have similar
clinical outcomes with fewer radiolucencies than observed with the
cemented device. However, before its widespread use it is necessary
to clarify contraindications and assess the complications. This
requires a larger study than any previously published. We present a prospective multicentre series of 1000 cementless
OUKRs in 881 patients at a minimum follow-up of one year. All patients
had radiological assessment aligned to the bone–implant interfaces
and clinical scores. Analysis was performed at a mean of 38.2 months
(19 to 88) following surgery. A total of 17 patients died (comprising
19 knees (1.9%)), none as a result of surgery; there were no tibial
or femoral loosenings. A total of 19 knees (1.9%) had significant
implant-related complications or required revision. Implant survival
at six years was 97.2%, and there was a partial radiolucency at
the bone–implant interface in 72 knees (8.9%), with no complete radiolucencies.
There was no significant increase in complication rate compared
with cemented fixation (p = 0.87), and no specific contraindications
to cementless fixation were identified. Cementless OUKR appears to be safe and reproducible in patients
with end-stage anteromedial osteoarthritis of the knee, with radiological
evidence of improved fixation compared with previous reports using
cemented fixation. Cite this article:
We performed a randomised controlled trial comparing
computer-assisted surgery (CAS) with conventional surgery (CONV)
in total knee replacement (TKR). Between 2009 and 2011 a total of
192 patients with a mean age of 68 years (55 to 85) with osteoarthritis
or arthritic disease of the knee were recruited from four Norwegian
hospitals. At three months follow-up, functional results were marginally
better for the CAS group. Mean differences (MD) in favour of CAS
were found for the Knee Society function score (MD: 5.9, 95% confidence
interval (CI) 0.3 to 11.4, p = 0.039), the Knee Injury and Osteoarthritis
Outcome Score (KOOS) subscales for ‘pain’ (MD: 7.7, 95% CI 1.7 to
13.6, p = 0.012), ‘sports’ (MD: 13.5, 95% CI 5.6 to 21.4, p = 0.001)
and ‘quality of life’ (MD: 7.2, 95% CI 0.1 to 14.3, p = 0.046).
At one-year follow-up, differences favouring CAS were found for
KOOS ‘sports’ (MD: 11.0, 95% CI 3.0 to 19.0, p = 0.007) and KOOS
‘symptoms’ (MD: 6.7, 95% CI 0.5 to 13.0, p = 0.035). The use of
CAS resulted in fewer outliers in frontal alignment (>
3° malalignment),
both for the entire TKR (37.9% Cite this article:
We report the results of revision total knee
replacement (TKR) in 26 patients with major metaphyseal osteolytic defects
using 29 trabecular metal cones in conjunction with a rotating hinged
total knee prosthesis. The osteolytic defects were types II and
III (A or B) according to the Anderson Orthopaedic Research Institute
(AORI) classification. The mean age of the patients was 72 years
(62 to 84) and there were 15 men and 11 women. In this series patients had
undergone a mean of 2.34 previous total knee arthroplasties. The
main objective was to restore anatomy along with stability and function
of the knee joint to allow immediate full weight-bearing and active
knee movement. Outcomes were measured using Knee Society scores,
Oxford knee scores, range of movement of the knee and serial radiographs.
Patients were followed for a mean of 36 months (24 to 49). The mean
Oxford knee clinical scores improved from 12.83 (10 to 15) to 35.20
(32 to 38) (p <
0.001) and mean American Knee Society scores
improved from 33.24 (13 to 36) to 81.12 (78 to 86) (p <
0.001).
No radiolucent lines suggestive of loosening were seen around the trabecular
metal cones, and by one year all the radiographs showed good osteo-integration.
There was no evidence of any collapse or implant migration. Our
early results confirm the findings of others that trabecular metal
cones offer a useful way of managing severe bone loss in revision
TKR. Cite this article:
Between 1987 and 2006 we performed a modified Thompson’s quadricepsplasty on 40 fracture-related stiff knees and followed the patients for a mean of 7.9 years (2 to 11.1). The factors affecting the final gain of movement were investigated. A total of 15 knees required lengthening of the rectus femoris. The mean flexion gain was 70.2° (42.3° to 112.5°). According to Judet’s criteria, the results were excellent in 30 knees, good in seven, and fair in three. The range of movement which was achieved intra-operatively was related to the gain of knee flexion on univariate analysis. Five patients had complications: deep infection in one, recurrent patellar dislocation in one, and rupture of the extensor mechanism in three. This modified technique gives satisfactory results. Achieving maximum knee flexion intra-operatively seems to be the most important factor in enhancing the outcome in patients with stiffness of the knee following fracture.
The lateral compartment is predominantly affected
in approximately 10% of patients with osteoarthritis of the knee. The
anatomy, kinematics and loading during movement differ considerably
between medial and lateral compartments of the knee. This in the
main explains the relative protection of the lateral compartment
compared with the medial compartment in the development of osteoarthritis.
The aetiology of lateral compartment osteoarthritis can be idiopathic,
usually affecting the femur, or secondary to trauma commonly affecting
the tibia. Surgical management of lateral compartment osteoarthritis
can include osteotomy, unicompartmental knee replacement and total
knee replacement. This review discusses the biomechanics, pathogenesis
and development of lateral compartment osteoarthritis and its management. Cite this article:
Medium-term survivorship of the Oxford phase
3 unicompartmental knee replacement (UKR) has not yet been established
in an Asian population. We prospectively evaluated the outcome of
400 phase 3 Oxford UKRs in 320 Korean patients with a mean age at
the time of operation of 69 years (48 to 82). The mean follow-up
was 5.2 years (1 to 10). Clinical and radiological assessment was
carried out pre- and post-operatively. At five years, the mean Knee
Society knee and functional scores had increased significantly from
56.2 (30 to 91) pre-operatively to 87.2 (59 to 98) (p = 0.034) and
from 59.2 (30 to 93) to 88.3 (50 to 100) (p = 0.021), respectively.
The Oxford knee score increased from a mean of 25.8 (12 to 39) pre-operatively
to 39.8 (25 to 58) at five years (p = 0.038). The ten-year survival
rate was 94% (95% confidence interval 90.1 to 98.0). A total of
14 UKRs (3.5%) required revision. The most common reason for revision
was dislocation of the bearing in 12 (3%). Conversion to a total
knee replacement was required in two patients who developed osteoarthritis
of the lateral compartment. This is the largest published series of UKR in Korean patients.
It shows that the mid-term results after a minimally invasive Oxford
phase 3 UKR can yield satisfactory clinical and functional results
in this group of patients.
We assessed the reliability, accuracy and variability of closed-wedge high tibial osteotomy (HTO) using computer-assisted surgery compared to the conventional technique. A total of 50 closed-wedge HTO procedures were performed using the navigation system, and compared with 50 HTOs that had been performed with the conventional technique. In the navigation group, the mean mechanical axis prior to osteotomy was varus 8.2°, and the mean mechanical axis following fixation was valgus 3.6°. On the radiographs the mean pre-operative mechanical axis was varus 7.3°, and the mean post-operative mechanical axis was valgus 2.1°. There was a positive correlation between the measured data taken under navigation and by radiographs (r >
0.3, p <
0.05). The mean correction angle was significantly more accurate in the navigation group (p <
0.002). The variability of the correction was significantly lower in the navigation group (2.3°
Patellofemoral joint degeneration is often considered a contraindication to medial unicompartmental knee replacement. We examined the validity of this preconception using information gathered prospectively on the intra-operative status of the patellofemoral joint in 824 knees in 793 consecutive patients who underwent Oxford unicondylar knee replacement for anteromedial osteoarthritis. All operations were performed between January 1998 and September 2005. A five-point grading system classified degeneration of the patellofemoral joint from none to full-thickness cartilage loss. A subclassification of the presence or absence of any full-thickness cartilage loss was subsequently performed to test selected hypotheses. Outcome was evaluated independently by physiotherapists using the Oxford and the American Knee Society Scores with a minimum follow-up of one year. Full-thickness cartilage loss on the trochlear surface was observed in 100 of 785 knees (13%), on the medial facet of the patella in 69 of 782 knees (9%) and on the lateral facet in 29 of 784 knees (4%). Full-thickness cartilage loss at any location was seen in 128 knees (16%) and did not produce a significantly worse outcome than those with a normal or near-normal joint surface. The severity of the degeneration at any of the intra-articular locations also had no influence on outcome. We concluded that, provided there is not bone loss and grooving of the lateral facet, damage to the articular cartilage of the patellofemoral joint to the extent of full-thickness cartilage loss is not a contraindication to the Oxford mobile-bearing unicompartmental knee replacement.