Knee arthroscopy can be used for ligamentous repair, reconstruction and to reduce burden of infection. Understanding and feeling confident with knee arthroscopy is therefore a highly important skillset for the orthopaedic surgeon. However, with limited training or experience, furthered by reduced practical education due to COVID-19, this skill can be under-developed amongst trainee surgeons. At a single institution, ten junior doctors (FY1 to CT2), were recruited as a part of a five, two-hour session, training programme utilising the Simbionix® ARTHRO Mentor knee arthroscopy simulator, supplemented alongside educational guidance with a consultant orthopaedic knee surgeon. All students had minimal to no levels of prior arthroscopic experience. Exercises completed included maintaining steadiness, image centring and orientation, probe triangulation, arthroscopic knee examination, removal of loose bodies and meniscectomy. Pre and post experience questionnaires and quantitative repeat analysis on simulation exercises were undertaken to identify levels of improvement.Introduction
Methods
Knee arthroscopy can be used for ligamentous repair, reconstruction and to reduce burden of infection. Understanding and feeling confident with knee arthroscopy is therefore a highly important skillset for the orthopaedic surgeon. However, with limited training or experience, furthered by reduced practical education due to COVID-19, this skill can be under-developed amongst trainee surgeons. At a single institution, ten junior doctors (FY1 to CT2), were recruited as a part of a five, two-hour session, training programme utilising the Simbionix® ARTHRO Mentor knee arthroscopy simulator, supplemented alongside educational guidance with a consultant orthopaedic knee surgeon. All students had minimal to no levels of prior arthroscopic experience. Exercises completed included maintaining steadiness, image centering and orientation, probe triangulation, arthroscopic knee examination, removal of loose bodies, and meniscectomy. Pre and post-experience questionnaires and quantitative repeat analysis on simulation exercises were undertaken to identify levels of improvement.Abstract
Introduction
Methods
No proven long-term joint-preserving treatment options exist for patients with irreparable meniscal damage. This study aimed to assess gait kinematics and contact pressures of novel fibre-matrix reinforced polyvinyl alcohol-polyethylene glycol (PVA-PEG) hydrogel meniscus implanted ovine stifle joints against intact stifles in a gait simulator. The gait simulator controlled femoral flexion-extension and applied a 980N axial contact force to the distal end of the tibia, whose movement was guided by the joint natural ligaments (Bartolo; ORS 2021;p1657- LB). Five right stifle joints from sheep aged >2 years were implanted with a PVA-PEG total medial meniscus replacement, fixed to the tibia via transosseous tunnels and interference screws. Implanted stifle joint contact pressures and kinematics in the simulator were recorded and compared to the intact group. Contact pressures on the medial and lateral condyles were measured at 55° flexion using Fujifilm Prescale Low Pressure film inserted under the menisci. 3D kinematics were measured across two 30 second captures using the Optotrak Certus motion-tracking system (Northern Digital Inc.). Medial peak pressures were not significantly different between the implanted and intact groups (p>0.4), while lateral peak pressures were significantly higher in the implanted group (p<0.01). Implanted stifle joint kinematics in the simulator did not differ significantly from the intact baseline (p>0.01), except for in distraction-compression (p<0.01). Our findings show that the fibre-matrix reinforced PVA-PEG hydrogel meniscal replacement restored the medial peak contact pressures. Similar to published literature (Fischenich; ABE 2018;46(11):1–12), the lateral peak pressures in the implanted group were higher than the intact. Joint kinematics were similar across groups, with slightly increased internal-external rotation in the implanted group. These findings highlight the effectiveness of the proposed approach and motivate future work on the development of a total meniscal replacement.
Due to their radiolucency and favourable mechanical properties, carbon fibre nails may be a preferable alternative to titanium nails for oncology patients. We aim to compare the surgical characteristics and short-term results of patients who underwent intramedullary fixation with either a titanium or carbon fibre nail for pathological long-bone fracture. This single tertiary-institutional, retrospectively matched case-control study included 72 patients who underwent prophylactic or therapeutic fixation for pathological fracture of the humerus, femur, or tibia with either a titanium (control group, n = 36) or carbon fibre (case group, n = 36) intramedullary nail between 2016 to 2020. Patients were excluded if intramedullary fixation was combined with any other surgical procedure/fixation method. Outcomes included operating time, blood loss, fluoroscopic time, and complications. Fisher’s exact test and Mann-Whitney U test were used for categorical and continuous outcomes, respectively.Aims
Methods
Tibial tubercle osteotomy (TTO) is a complex surgical procedure with a significant risk of complications, which include nonunion and tibial fracture. To determine whether an additional suture tape augmentation can provide better biomechanical stability compared with standard screw fixation. Five matched pairs of human cadaveric knees were divided into 2 groups: the first group underwent standard TTO fixation with 2 parallel screws. The second group underwent a novel fixation technique, in which a nonabsorbable suture tape (FiberTape) in a figure-of-8 construct was added to the standard screw fixation. Tubercular fragment migration of >50% of the initial distalization length was defined as clinical failure Tubercular fragment displacement during cyclic loading and pull-to-failure force were recorded and compared between the 2 groups.Abstract
Introduction
Methods
Cam morphology develops during adolescence and predisposes individuals to future hip pain and osteoarthritis. An improved understanding of cam development is required to determine whether the process is modifiable. The aim of this study was to characterise the risk factors, timing, and pathogenesis of cam formation.Background
Hypothesis/Purpose
Infections in orthopaedic surgery are costly, debilitating complications. The search for new treatments and prevention strategies has led to the use of antibiotic-filled calcium sulfate (CaS) as a bone void filler that is both safe and effective. The purpose of this study was to examine the available data on the efficacy of this technology. A literature search was performed for studies that evaluated the use of antibiotic-loaded CaS cement in orthopaedics published between inception of the databases to 2017. Selected studies included randomized controlled trials (RCTs) and observational studies published in the English language that met the following criteria: 1) patients underwent an orthopaedic procedure; 2) CaS cement with an antibiotic was used; and 3) at least one of our outcomes were mentioned. Outcomes included resolution of infection, complications related to treatment, subsequent surgeries, overall infection rate, fracture union rate, clinical outcomes, and wound complications. A total of 17 studies were included.Purpose
Methods
A meta-analysis was performed to compare rate of SSI after application of chlorhexidine vs. iodine in total joint arthroplasty. Chlorhexidine had significantly lower odds of SSI. Surgical site infections (SSI) are a significant source of morbidity and mortality. The optimal preoperative skin preparation in lower extremity total joint arthroplasty (TJA) remains debatable between chlorhexidine and iodine-containing solutions. This meta-analysis sought compare SSI rates between chlorhexidine cloth application the night before surgery plus povidone-iodine-alcohol (povidone-iodine) solution at surgery or only povidone-iodine at surgery.Summary
Introduction
Patients who have multiple sclerosis (MS) may be at increased risk of developing complications after total hip arthroplasty (THA). The purpose of this study was to compare: 1) implant survivorship; 2) functional outcomes; 3) complication rates; and 4) radiographic findings after THA between MS patients and a matched cohort. A single institutional database was reviewed for patients who had a diagnosis of MS and underwent a THA. Thirty-four patients (41 hips) were matched to a 2:1 cohort who did not have MS using based on age, sex, body mass index (BMI), and Charlson/Deyo scores. This resulted in a matching cohort of 80 patients (82 hips). The available medical records were reviewed. Functional outcomes and complications were assessed. Postoperative radiographs were evaluated. The matching cohort had higher all-cause survivorship at 4-years postoperatively (99 vs. 93%). There were 3 revisions in the MS cohort and 0 revisions in the matching cohort. The MS cohort had lower mHHS scores (66 vs.74 points, p<0.001), lower HOOS JR scores (79 vs. 88 points, p<0.01), required more physical therapy (5 vs. 3 weeks, p<0.01), and took longer to return to their baseline functional level (7 vs. 5 weeks, p<0.05). MS patients had higher rate of complications (6 vs. 1, p<0.05). Excluding revision cases, there was no additional radiographic evidence of progressive radiolucency, loosening, or subsidence. We found that MS patients had lower implant survivorship, lower functional outcome scores, and increased complication rates. These findings may help orthopaedists to have a better knowledge of how MS patients do after THA.
Unicompartmental knee arthroplasty (UKA) is a demanding procedure, with tibial component subsidence or pain from high tibial strain being potential causes of revision. The optimal position in terms of load transfer has not been documented for lateral UKA. Our aim was to determine the effect of tibial component position on proximal tibial strain. A total of 16 composite tibias were implanted with an Oxford Domed Lateral Partial Knee implant using cutting guides to define tibial slope and resection depth. Four implant positions were assessed: standard (5° posterior slope); 10° posterior slope; 5° reverse tibial slope; and 4 mm increased tibial resection. Using an electrodynamic axial-torsional materials testing machine (Instron 5565), a compressive load of 1.5 kN was applied at 60 N/s on a meniscal bearing via a matching femoral component. Tibial strain beneath the implant was measured using a calibrated Digital Image Correlation system.Objectives
Methods
Because of the low cost and easy access, surgical video has become a popular method of acquiring surgical skills outside operating rooms without disrupting normal surgical flow. However, currently existing video systems all use a single point of view (POV). Some complex orthopedic procedures, such as joint replacement, require a level of accuracy in several dimensions. So single and fixed POV video may not be enough to provide all the necessary information for educational and training purposes. The aim of our project was to develop a novel multiple POV video system and evaluate its efficacy as an aid for learning joint replacement procedure compared with traditional method. Based on the videos of a hip resurfacing procedure performed by an expert orthopedic surgeon captured by 8 cameras fixed all around the operating table, we developed a novel multiple POV video system which enables users to autonomously switch between optimal viewpoints (Figure 1). 30 student doctors (undergraduate years 3–5 and naive to hip resurfacing procedure) were recruited and randomly allocated to 2 groups: experiment group and control group, and were assigned to learn the procedure using multiple or single POV video systems respectively. Before learning they were first asked to complete a multiple choicetest designed using a modified Delphi technique with the advice and feedback sought from 4 experienced orthopedic surgeons to test the participants' baseline knowledge of hip resurfacing procedure. After video learning, they were asked to answer the test again to verify their gained information and comprehension of the procedure, followed by a 5-point Likert-scale questionnaire to demonstrate their self-perception of confidence and satisfaction with the learning experience. The scores in the 2 tests and in the Likert-scale questionnaire were compared between 2 groups using Independent-Samples t-test (for normally distributed data) or Mann-Whitney U test (for non-normally distributed data). Statistical significance was set as p<0.05.Introduction
Materials and Methods
Patient Specific Instrumentation (PSI) has the potential to allow surgeons to perform procedures more accurately, at lower cost and faster than conventional instrumentation. However, studies using PSI have failed to convincingly demonstrate any of these benefits clinically. The influence of guide design on the accuracy of placement of PSI has received no attention within the literature. Our experience has suggested that surgeons gain greater benefit from PSI when undertaking procedures they are less familiar with. Lateral unicompartmental knee replacement (UKR) is relatively infrequently performed and may be an example of an operation for which PSI would be of benefit. We aimed to investigate the impact on accuracy of PSI with respect to the area of contact, the nature of the contact (smooth or studded guide surfaces) and the effect of increasing the number of contact points in different planes. A standard anatomy tibial Sawbone was selected for use in the study and a computed tomography scan obtained to facilitate the production of PSI. Nylon PSI guides were printed on the basis of a lateral UKR plan devised by an orthopaedic surgeon. A control PSI guide with similar dimensions to the cutting block of the Oxford Phase 3 UKR tibial guide was produced, contoured to the anterior tibial surface with multiple studs on the tibial contact surface. Variants of this guide were designed to assess the impact of design features on accuracy. These were: a studded guide with a 40% reduction in tibial contact area, a non-studded version of the control guide, the control guide with a shim to provide articular contact, a guide with an extension to allow distal referencing at the ankle and a guide with a distal extension and an articular shim. All guides were designed with an appendage that facilitated direct attachment to a navigation machine (figure 1). 36 volunteers were asked to place each guide on the tibia with reference to a 3D model of the operative plan. The order of placement was varied using a counterbalanced latin square design to limit the impact of the learning effect. The navigation machine recorded deviations from the plan in respect of proximal-distal and medial-lateral translations as well as rotation around all three axes. Statistical analysis was performed on the compound translational and rotational errors for each guide using ANOVA with Bonferroni correction with statistical significance at p<0.05.Introduction
Method
Stiffness after total knee arthroplasty is a common occurrence. Despite its prevalence, little is known as to which patients are at risk for poor range of motion after total knee arthroplasty. The purpose of this study was to determine the risk factors for manipulation under anesthesia (MUA) after total knee arthroplasty (TKA). Using a single institution registry, 160 patients who underwent a manipulation under anesthesia after total knee arthroplasty between 2007 and 2013 were retrospectively evaluated. Each patient was 1:1 matched by age, gender and laterality to a control group of 160 patients who did not require MUA after TKA. Risk factors for MUA were assessed, and included medical co-morbidities, BMI, prior operations, and preoperative range of motion.Introduction
Methods
Intramedullary nailing of tibial fractures is commonplace and freehand techniques are increasingly popular. The standard freehand method has the knee of the injured leg flexed over a radio-lucent bolster. This requires the imaging C-arm to swing from antero-posterior to lateral position several times. Furthermore, guide wire placement; reaming and nail insertion are all performed well above most surgeons' shoulder height. If instead the leg is hung over the edge of the table, the assistant must crouch and hold the leg until the nail is passed beyond the fracture. We describe a method of nailing which is easier both for the surgeons and the (often inexperienced) radiographer and present a series of 87 consecutive cases managed with this technique.
Currently the debate continues in definitive fixation method for complex tibial plateau fractures. The aim of surgical management remains prevention of further damage to the articular cartilage, whilst avoiding iatrogenic risks - Low Risk Surgery (LRS). The purpose of this study was to determine the functional impact, clinical radiological outcome following tibial plateau fractures treated with either external fixation or internal fixation. 124 Schatzker IV-VI tibial plateau fractures were reviewed following surgical fixation. Fractures analysed included 24 type IV, 20 type V and 80 type VI tibial plateau fractures. The majority of Schatzker IV fractures were treated with internal fixation, but 67 of 80 Schatzker VI fractures were treated with the Ilizarov method. The average IOWA knee score, was 86 (16 to 100) and the average range of motion was 133 degrees (60 to 150). There were no differences between the circular fixator group and the internal fixation group in terms of range of motion or IOWA scores. There were comparable functional outcomes and complication rates between both groups. In summary patients with high energy tibial plateau fracture treated with internal or external fixation, have a good chance of achieving satisfactory long term knee function.
We reviewed our results and complications of using a pre-bent 1.6mm Kirschner wire (K-wire) for extra-articular metacarpal fractures. The surgical procedure was indicated for angulation at the fracture site in a true lateral radiograph of at least 30 degrees and/or in the presence of a rotatory deformity. A single K-wire is pre-bent in a lazy-S fashion with a sharp bend at approximately 5 millimetres and a longer smooth curve bent in the opposite direction. An initial entry point is made at the base of the metacarpal using a 2.5mm drill by hand. The K-wire is inserted blunt end first in an antegrade manner and the fracture reduced as the wire is passed across the fracture site. With the wire acting as three-point fixation, early mobilisation is commenced at the metacarpo-phalangeal joint in a Futuro hand splint. The wire is usually removed with pliers post-operatively at four weeks in the fracture clinic. We studied internal fixation of 18 little finger and 2 ring finger metacarpal fractures from November 2007 to August 2009. The average age of the cohort was 25 years with 3 women and 17 men. The predominant mechanism was a punch injury with 5 diaphyseal and 15 metacarpal neck fractures. The time to surgical intervention was a mean 13 days (range 4 to 28 days). All fractures proceeded to bony union. The wire was extracted at an average of 4.4 weeks (range three to six weeks). At an average follow up of 8 weeks, one fracture had to be revised for failed fixation and three superficial wound infections needed antibiotic treatment. With this simple and minimally invasive technique performed as day-case surgery, all patients were able to start mobilisation immediately. The general outcome was good hand function with few complications.
The aim of this study was to compare the short-term and mid-term outcome of lateral UKRs using a single prosthesis, the AMC Uniglide knee implant. Between 2003 and 2010, seventy lateral unicompartmental knee replacements (mean patient age 63.6±12.7 years) were performed at our unit for isolated lateral compartmental disease. Range of knee motion and functional outcome measures including the American Knee Society (AKSS), Oxford (OKS) and WOMAC scores were recorded from 19 knees at five years' post-operatively and compared to 35 knees at two-years and 53 knees at one-year post-op.Purpose
Methods
Kneeling ability is better in unicompartmental than total knee arthroplasty. There is also an impression that mobile bearing knees achieve better functional outcome than their fixed bearing cousins in unicompartmental and to a lesser extent total joint arthroplasty. In the UK, the market leading unicompartmental replacement is mobile bearing. To analyse kneeling ability after total and unicompartmental knee replacement using mobile and fixed bearing inserts.Introduction
Aim
Trochlear dysplasia (TD) is still poorly recognised, generally considered uncommon and to present purely as persistent patella dislocation. 87 patients diagnosed as having TD by a true lateral X-ray, MRI scan or at surgery were sent a questionnaire about their initial symptoms. 60% had suffered adolescent anterior knee pain. Lack of trust, wobbling, stair problems, giving way and catching were also common symptoms. Only 66% had ever suffered a dislocation, their troubles had started at 12 years of age. Most had undergone unsuccessful realignment procedures and many had developed premature lateral patello-femoral arthritis.Introduction
Diagnosis
Between 1989 and 1992 102 knees adjudged suitable for Unicompartmental replacement (UKR) were randomised to receive either a St Georg Sled UKR or a Kinematic modular total knee replacement (TKR). The early results demonstrated that the UKR group had less complications, and more rapid rehabilitation. At 5 years there were equal failures but the UKR group had more excellent results and a greater range of movement. Despite this doubt persisted about whether these advantages would be maintained these cases have been followed regularly by a research nurse at 8, 10, 12 years. We now report the final outcome at 15 years. 43 patients (45 knees) have died with all their knees intact. Throughout the review period the Bristol Knee Scores (BKS) of the UKR group have been better and at 15 years 77% and 53% of the surviving UKRs and TKRs achieve an excellent score. 6 TKRs and 4 UKRs have failed during the 15 years of the review. The better early results with UKR are maintained at 15 years with no greater failure rate. The median BKS scores of the UKR group was 91.1 at five years and 92 at 15 years suggesting little functional deterioration in either the prosthesis or remainder of the joint. These results would seem to justify the increased use of UKR.Conclusion
We aimed to measure cerebral microemboli load during total hip [THA] and knee arthroplasty (TKA) using transcranial Doppler ultrasound (TCD) and to investigate whether cerebral embolic load influences neuropsychiatric outcome. The timing of the microemboli was also related to certain surgical activities to determine if a specific relationship exists and the presence of a patent foramen ovale was investigated. Patients undergoing primary THA and TKA underwent a battery of ten neuropsychiatric tests pre-operatively and at 6 weeks and 6 months post-operatively. Microembolic load was recorded using TCD onto VHS tape for subsequent analysis. Patent foramen ovale detection was performed using bolus intravenous injection of agitated saline followed by valsalva manoeuvre. The timing of specific surgical steps was recorded for each operation and embolic load calculated for that period. All patients were assessed for quality of life and orthopaedic outcome measures. 45 THA patients and 50 TKA patients were studied. Cerebral microembolisation occurred in 35% of all patients (10 THA patients and 19 TKA patients). Mean microembolic load was 2.8 per patient for THA and 3.76 per patient for TKA patients. PFO was detected in 29 patients overall. Insertion of the femoral component and deflation of the tourniquet were associated with a larger microembolic loads. Neuropsychiatric outcome was not affected by the low embolic loads. Quality of life and Orthopaedic outcome at 6 months was good. Cerebral microembolisation occurs in a significant proportion of patients during total hip and knee arthroplasty. The presence of a patent foramen ovale does not appear to influence the incidence of microembolisation or load. Specific surgical activities are associated with generating greater embolic loads and methods of avoiding these emboli such as venting the femur may minimise complications and optimise outcomes. Neuropsychiatric outcomes do not seem to be affected by microembolisation of the brain during total joint arthroplasty.Results
Conclusion
Unicompartmental knee replacements (UKR) converted to total knee replacements (TKR) have often been viewed with scepticism because of the perceived difficulty of the revision and because revision procedures generally do less well than primaries. This is a prospective review of TKRs converted from a UKR between 1982 and 2000. We present the survivorship of a 77 patient cohort and the clinical results of 35 patients. All information was recorded at the time of surgery onto a database and patients have been regularly reviewed since.Background
Methods
The Bristol Knee Group has prospectively followed the results of over 500 isolated patellofemoral arthroplasties. Initial experience with the Lubinus prosthesis was disappointing. The main causes of failure were mal-tracking and instability leading to excessive polythene button wear and disease progression in the tibio femoral joint. This experience resulted in the design of a new prosthesis to correct the tracking problems and improve the wear. We have now performed over 425 Avon arthroplasties with a maximum follow-up of 9 years. Survivorship at 5 years and the functional outcome have been reported with 95.8% survivorship, and improved function with Oxford score from 18 to 39 points out of 48. There have been 14 cases with mal-tracking (3%). Several of these cases have required proximal or distal realignment with the Elmslie or Insall procedures. Two knees with patella alta required distalisation of the tibial tubercle. Symptomatic progression of the arthritic disease in the medial or lateral tibio-femoral compartments has occurred in 28 cases (7%) causing recurrent joint pain. Radiographic follow-up has shown a higher rate of disease progression emphasising the importance of careful assessment of patients prior to operation. We have investigated 8 cases of persistent unexplained pain. Analysis of these cases suggests 3 possible causes. An extended anterior cut leading to overstuffing, insufficient external rotation and over sizing of the femoral component leading to medial or lateral retinacular impingement. Six of these cases have been successfully treated by revision of the femoral component leading to dramatic resolution of the symptoms.Introduction
Results
Although good long term results for fixed bearing uni-compartmental knee replacements (UKRs) have been reported mobile bearings predominate in some parts of the world. Three prospective studies have been undertaken comparing the short and medium term outcomes of fixed and mobile UKRs.
A 5 year comparative cohort study of 47 Oxford mobile bearing and 57 St Georg Sled fixed bearing UKRs. A 2 year study of 50 fixed and 50 mobile bearing AMC Uniglide UKRs.(The implant system allows implantation of either a fixed or mobile tibial component with the same femoral component.) The 1 year results of a randomised controlled trial of 38 fixed and 33 mobile AMC Uniglide UKRs in patients under 70. In all groups the preoperative sex mix, average age and knee scores were extremely similar. All patients were assessed both pre and postoperatively by a research nurse and radiographs were taken; the results were entered on the Bristol Knee database.
Multiple problems were encountered, perhaps because of the introduction of MIS, but at 5 years 11 Oxford and 4 Sleds had failed. The major problem with the mobile bearing implant was instability though tibial fractures were also seen. Both groups had three cases of arthritic progression and loose cement was seen twice in the fixed bearing group. – Amongst the remaining patients the median scores for the Sled were better. Bristol Knee Score (Max 100) 95:90; Oxford (Max 48) 39:37; and reduced WOMAC (Best score 12) 18:24. 2 bearing exchanges and 3 revisions were needed in the mobile group with none in the fixed group. Again all scores were better for the fixed group. American Knee Score (AKS) (Max 200) 195:185; Oxford (Max48) 39:37; and reduced WOMAC (Max 12) 19:20. One fixed bearing implant had been revised but none in the mobile group, however 3 randomised to receive a mobile bearing had a fixed bearing inserted because the surgeon was unhappy about bearing stability; all three are doing well. All knee scores at one year show the fixed bearing implant to be performing better. AKS (Max 200) 194:173; Oxford (Max48) 39:33; and WOMAC(Max) 12 18:22.
This observational study was undertaken to explore the relationship of the foot posture of patients with Medial Compartment Osteoarthritis of the knee (MCOA), patients with hip osteoarthritis (OA) and a healthy control group, using the Foot Posture Index (FPI). Goniometric measurement of talocrural dorsiflexion was also included. The relationship of foot posture to MCOA and hip osteoarthritis OA has not been explored although in other medical fields, such as neurology and sports medicine, the relationship between foot posture, lower limb pain and function has been acknowledged. In view of the current high incidence of lower limb OA, any investigation of associations that may lead to improved assessment and conservative management is worthy of consideration. Currently, systematic examination of the foot is not undertaken in routine clinical assessment of patients with lower limb OA and, if this were to be introduced, there would be difficulty in selecting suitable clinical outcome measures. The recent development of the Foot Posture Index (FPI) has addressed the need for a diagnostic clinical tool that measures foot posture in multiple planes and anatomical segments Sixty participants took part: twenty patients with radiographic and clinical evidence of MCOA grade IV, twenty patients with radiographic and clinical evidence of stage IV OA hip, and twenty age-matched healthy volunteers as a control group. A one way Analysis of variance (ANOVA) was performed to investigate any differences between the 3 groups for foot posture using FPI scores and talocrural dorsiflexion measurements. This showed that there were significant differences between the groups (p<
0.001). Patients with MCOA had a high positive FPI score (indicating a pronated foot), patients with hip OA had a low negative FPI score (indicating a supinated foot). The healthy controls had a normal score distributed over a wider range than the other two groups. In addition, the results of the Pearsons test indicate that the FPI correlated positively with talocrural dorsiflexion (r = 0.55, p<
.001). Differences in foot characteristics may be influenced by specific treatment modalities such as gait reducation, orthotic provision, specific lower limb strengthening and stretching exercises. Foot assessment might therefore be a useful adjunct to conservative management of both MCOA and hip osteoarthritis.
99 knees were followed for 15 years, 21 knees for 20 years and four for 25 or more years. The average Bristol knee score of the surviving knees fell from 86 to 79 during the second decade, largely as a result of aging. A previous study of the St Georg. Fixed bearing UKR showed an 89% 10 year survivorship and this is now extended to 82% at 15 years and 76.5% at 20 years.
All patients completed the Oxford Knee Questionnaire preoperatively as well as at 1 and 2 years postoperatively. Their stated kneeling ability and total scores were analysed with a perfect score for kneeling ability being 4, and 48 the maximum total score.
There was a more striking difference with respect to kneeling ability with the fixed bearing variants performing better, (Rotaglide 1.4; 0.9 and Uniglide 1.9; 1.4), However, the greatest difference was between the UKR and TKR groups (UKR 1.7; TKR 1.2). Pre-operatively less than 2% of TKR patients (7% of the UKR patients) could kneel. Post-operatively, the patients’ kneeling ability improved with 21% for the mobile bearing, 32% of fixed bearing UKR patients. The TKR patients kneeling ability was 13% of the mobile, 26% of fixed bearing patients were able to kneel with little or no difficulty. In all groups the stated kneeling ability was poor with less than 50% of any group being able to kneel with ease or only minor difficulty.
Since 1996 over 400 isolated patellofemoral replacements using the Avon prosthesis have been undertaken in Bristol. As a result of the usually gratifying outcomes seen in patients over 55 years old, the indications for this surgery were soon extended to include the many younger patients who have severely disabling patellofemoral disease. We present results from a prospective cohort study of patients under 55 years of age at the time of surgery. 110 knees in 86 patients (median age 47 years, range 24–54) have been treated with Avon patellofemoral replacement (88 in females and 22 in males). Diagnoses included lateral facet OA (59 knees), patella dislocation (25 knees), trochlear dysplasia (41 knees) and post patellectomy instability (7 knees). 79 knees had undergone previous surgery. 17 knees required additional intra-operative procedures including 11 lateral releases and 2 patella realignments. All patients were assessed pre-operatively and at regular intervals using the Oxford, Bristol and WOMAC scores. All knees were scored preoperative and only one knee has been lost to follow-up due to the patient’s death, which was unrelated to surgery. Post-operative Oxford knee scores have been obtained for 106 knees with follow-up between 8 months and 8 years (mean follow-up 24 months). The mean Oxford score improved from 18 preoperatively to 31 at latest review. Bristol and WOMAC scores showed similar improvements. 16 knees required post-operative additional procedures including 6 lateral releases, 3 patella realignments and 11 revisions. Of the revisions 5 were for progression of tibiofemoral OA but none of these were knees with trochlear dysplasia. Equally good mean scores were seen when comparing patients with the 3 main underlying pathologies (trochlear dysplasia, patellar dislocation and lateral facet OA). At least 37% of the patients studied had pre-existing trochlear dysplasia and the majority of these patients report onset of symptoms, often patellar dislocation, in the first three decades of life. More than 90% of patients were overweight or obese according to their BMI at the time of surgery. Many of this type of patient, with disabling symptoms, wish to “live now”. The short-term improvements are frequently dramatic. As yet there is no suggestion of prosthetic failure. Revision presents little difficulty since minimal bone is resected in the primary proceedure. Radiological deterioration of the tibio femoral joint is seen in some cases of primary OA but not with trochlear dysplasia.
Only two trochlea components were loose at the time of revision and one patella had a large amount of macroscopic wear. All other components were found to be well fixed with minimal wear at the time of revision. There were no difficulties in removing either component. No cases required augments or stemmed femoral components due to bone loss. Patients undergoing revision surgery did report improvement in their post revision outcome scores compared with their pre-operative scores. The average Oxford Knee Score improved from 17 to 23, Bristol Knee Pain Scores improved from 11 to 20 and Bristol Knee Functional Scores improved from 15 to 16. These results are poorer than those recorded by the overall cohort of primary PFA.
611 patients were involved with a mean age of 68 years. Residual pain following surgery was assessed with either the Oxford Knee Score (OKS) or the WOMAC score. The patients were followed up at one and two years postoperatively by a Research nurse and the findings recorded prospectively on the Bristol Knee database.
35 patients were included in the trial; they were randomized to have DBM and autograft on one side, and autograft alone on other side to side. Patients were followed up with interval radiographs for total of 24mons. To date 20 patients have completed minimum 12mons follow up. The mineralization of fusion mass lateral to the instrumentation on each side was graded Absent, Mild (<
50%), Moderate (>
50%) or Complete fusion (100%). The assessment was made by two orthopaedic consultants and a musculoskeletal radiologist who were blinded to graft assignment.
Data was also prospectively collected on 215 UKR patients who received the same Unicompartmental implant (AMC, Uniglide, Corin, UK). One hundred and thirty six patients (Mean age: 62 yrs) had a mobile insert and 79 (mean age: 65 yrs) a fixed insert. All patients completed the Oxford Knee Questionnaire preoperatively as well as at 1 and 2 years postoperatively. Their stated kneeling ability and total scores were analysed with a perfect score for kneeling ability being 4 and 48 the maximum total score.
There was a more striking difference with respect to kneeling ability with the fixed- bearing variants performing better, (Rotaglide 1.4; 0.9 and Uniglide 1.9; 1.4), However, the greatest difference was between the UKR and TKR groups (UKR 1.7; TKR 1.2). Pre-operatively less than 2% of TKR patients (7% of the UKR patients) could kneel. Post-operatively, the patients’ kneeling ability improved with 21% for the mobile bearing, 32% of fixed bearing UKR patients. The TKR patients kneeling ability was 13% of the mobile, 26% of fixed bearing patients were able to kneel with little or no difficulty. In all groups the stated kneeling ability was poor with less than 50% of any group being able to kneel with ease or only minor difficulty.
The median pain score rose from 15/40 pre-operatively to 40 points at eight years. The median (MPS) rose from 10/30 points pre-operatively to 25 points at eight years. The median (OKS) rose from 18/48 pre-operatively to 38 at eight years. 87% of knees had mild or no pain at eight years. There were no cases of failure of the prosthesis itself. All 15 revisions resulted from progression of arthrititis in the tibio-femoral joint. The five-year survival rate for all causes with 86 cases at risk was 96%.
99 knees were followed for 15 years and 21 knees for 20 years. The average Bristol knee score of the surviving knees fell from 86 to 79 during the second decade. A previous study showed an 89% 10 year survivor-ship and this is now extended to 82% at 15 years and 76.5% at 20 years.
The purpose of this study was to determine the incidence of revision total knee replacement (TKR) within 5 years of the index procedure at a large multi-surgeon unit using a single prosthesis and to determine the cause of failure of those implants. This was a retrospective review of all primary Kine-max Plus TKR performed at the Avon Orthopaedic Center between 1.1.1990 and 1.1.2000. Cases were identified that required revision arthroplasty in any form within 5 years of the index procedure. Case notes and Xrays were reviewed to determine causes of failure. There were 2826 primary Kinemax Plus TKR performed during the study period. Of these 20 were known to have required revision surgery within 5 years. 8 were revised for deep infection of the prosthesis and 12 for aseptic causes. The overall incidence of premature failure of the Kinemax Plus TKR at 5 years was 0.71%. The incidence of aseptic premature failure at 5 years was 0.42%. Detailed examination of the clinical records indicated that some form of technical error at the time of the index arthroplasty was responsible for the early failure of 6 prostheses. This equates to 0.21% of the procedures performed. Aseptic loosening of the remaining 6 cases could not be attributed to a specific cause.
To quantify the intraoperative cerebral microemboli load during primary total knee arthroplasty (TKA) using transcranial Doppler ultrasound and to investigate whether a patent foramen ovale influences cerebral embolic load in general. Patients undergoing primary TKA, with no history of stroke, TIA, ongoing CNS disease or alcoholism were included. All operations were carried out under a standardised general anaesthetic and performed by two consultant orthopaedic surgeons. Microemboli l oad was recorded, using transcranial Doppler ultrasound (TCD), onto VHS tape for subsequent playback and analysis. Patent foramen ovale detection was performed using bolus intravenous injection of agitated saline followed by valsalva manoeuvre technique and TCD. Timing of specific surgical steps was recorded for each operation and emboli load calculated for that period.
Medial unicompartmental replacement (UKR) has been shown to have superior functional results to total knee replacement (TKR) in appropriately selected patients, and this has been associated with a resurgence of interest in the procedure. This may relate to evidence showing that the kinematic profile of UKR is similar to the normal knee, in comparison to TKR, which has abnormal kinematics. Concerns remain over the survivorship of UKR and work has suggested the anterior cruciate ligament (ACL) may become dysfunctional over time. Cruciate mechanism dysfunction would produce poor kinematics and instability providing a potential mechanism of failure for the UKR.
A cross sectional study was designed in which 24 patients who had undergone successful UKR were recruited and divided into early (2–5 years) and late (>
9 years) groups according to time since surgery. Patients performed flexion/extension against gravity, and a step up. Video fluoroscopy of these activities was used to obtain the Patellar Tendon Angle (PTA), the angle between the long axis of the tibia and the patella tendon, as a function of knee flexion. This is a previously validated method of assessing sagittal plane kinematics of a knee joint. This work suggests the sagittal plane kinematics of a fixed bearing UKR is maintained in the long term. There is no evidence that the cruciate mechanism has failed at ten years. However, increased tibial bearing conformity from ‘dishing’, and adequate muscle control, cannot be ruled out as possible mechanisms for the satisfactory kinematics observed in the long term for this UKA.
70 patients who underwent dynamic MRI scanning for chronic anterior knee pain were retrospectively evaluated. All patients had been symptomatic for over a year. 43 patients had been treated conservatively and 27 had undergone surgical procedures (arthroscopy -13, lateral release- 9, tibial tubercle transfer 5). The extent of subluxation, tilt and cartilage abnormalities on MRI scans, during resisted extension were assessed. Functional scoring (Oxford, Lysholm and Tegner scores) was done through questionnaires and correlated with the radiological findings. 54 (77%) patients were found to have some patellofemoral abnormality on the scans. Subluxation was the most common finding with mild subluxation in 30, moderate in 18 and severe in 17 knees. Mild tilt was seen in 26 knees and moderate to severe tilt in 14 knees. Tilt was found in association with subluxation except in 8 cases. Grade 1 and 2 cartilage wear were seen in 13 knees and Grade 3 and 4 in 21 knees. The “Tibial Tubercle to Trochlear Groove distance” (TTD) was measured in all knees and correlated with subluxation. The average distance was 13.5mm, 13.6mm and 18.8mm for mild, moderate and severe subluxation respectively. All patients with a TTD _ 20mm had moderate or severe subluxation. The specificity of a TTD _ 20mm for severe maltracking was 100% but the sensitivity was only 42%. The TTD appears to be the single most significant parameter determining patella tracking. We have proposed an algorithm for the surgical and non-surgical treatment of chronic anterior knee pain. We recommend lateral release for those with moderate and severe subluxation and a tibial tubercle transfer as well in those with a TTD _ 20mm. The functional scores did not zshow a significant correlation with the grading of subluxation.
Lowered by more than 5 mm Restored Elevated more than 5 mm