A “two-stage exchange” remains the gold standard for treatment of the infected TKA in North America. Although there is interest in “one-stage exchange” this technique is not as familiar to many US surgeons and it is unclear if the reported results of Europe can be translated to North American practice. Specific concerns include the “radicalness” of the debridement required (which oftentimes includes the collateral ligaments, hence the popularity of hinged implants where this approach is common) and the use of fully cemented stems, which are extremely difficulty to remove if infection recurs. Thus while the idea of a one stage exchange is attractive to many North American surgeons, careful study will be required to determine if success can be achieved with a more “conservative” debridement and the use of cementless stems which are preferred by some surgeons. The basic principles of a two-stage exchange include: Thorough debridement of all infected appearing foreign material and all cement; Placement of an interval antibiotic loaded spacer (note that the addition of antibiotics to bone cement is NOT FDA approved) – 4–6g of antibiotics per pkg of cement; typically vancomycin + tobramycin; Higher viscosity cement may be associated with higher elution; The combination of antibiotics also leads to higher elution. Antibiotic spacers can be “articulating” or “static”. Potential advantages of an articulating spacer include greater patient comfort and an easier approach at the second stage exchange as soft tissue tension and range of motion is maintained. However, these spacers are oftentimes more costly and can break or dislocate. The first stage is followed by approximately 6 weeks of organism specific IV antibiotics. An interdisciplinary approach with an infectious disease specialist, internal medicine and a nutritionist optimises outcomes. Our protocol then includes weekly ESR and CRP to monitor their trend. These labs are re-checked two weeks after cessation of antibiotics to ensure the trend has not changed. The knee is routinely aspirated at this time point and the fluid obtained sent for a synovial fluid WBC count with differential and cultures (although the value of such cultures is controversial). We have found that while the ESR and CRP are significantly lower than prior to removal of the infected implant, they often times DO NOT normalise and there is no specific cut-off value that predicts persistent infection.
Infection after total knee arthroplasty poses formidable challenges to the surgeon. Once an infection is diagnosed, the identification of the organism and its sensitivity to antibiotics is essential. The host's healing capacity is vital. Optimisation of modifiable comorbidities, supplemental nutrition and cessation of smoking can improve wound healing. Surgical goals include debridement of necrotic tissue and elimination of the dead space. Intravenous antibiotics and a two-stage protocol are the standard of care. At our institution, the first stage is performed with an implant and antibiotic-cement composite. This articulating spacer maintains limb length and tissue compliance. The patient can maintain a functional status between stages. Definitive reconstruction is more readily accomplished with this method in contrast to the static spacer approach. The clinical efficacy of this protocol has been well documented in the literature.
Deep periprosthetic infection after hip or knee arthroplasty is a disconcerting problem for patient and surgeon alike. The diagnosis of infection is sometimes obvious but frequently requires that the surgeon maintain a substantial index of suspicion for infection as the cause of pain or poor outcome after any joint arthroplasty. While surgical debridement with component retention is appropriate in a subgroup of patients with an acute periprosthetic infection most delayed and chronic infections are best treated with component resection. The pre-eminent role of two-stage exchange as the definitive treatment was established over 30 years ago. Two-stage exchange remains the gold-standard in treatment with an established track record from multiple centers and with multiple different types of infecting organisms. Some of the historical problems with two-stage exchange, such as limited mobility during the interval stage, have been mitigated with the development of effective articulating spacer techniques. Further, the emergence of drug resistant bacteria and the possibility of fungal infection make two-stage exchange the best choice for the majority of patients with deep periprosthetic joint infection in 2015.
Infection after TKA remains a common reason for reoperation, and represents a significant burden for the patient and health care system. Having effective treatment strategies, therefore, is important to ensure the highest possible rate of success, and the lowest possible rate of reoperation due to treatment failure. This lecture will focus on the chronically infected TKA, where treatment options include either one stage exchange or two stage exchange. Proponents of one stage exchange cite lower costs, less morbidity, and reasonable success rates when compared to two stage exchange protocols. One must realise that strict selection criteria are generally used by proponents of single stage exchange. Favorable pathogens, healthy hosts, good soft tissues, minimal bone loss, etc. are generally used as indications to consider one stage exchange. Such “ideal” clinical situations, however, are exceedingly rare. The overwhelming majority of infected TKA in my practice involve resistant bacteria, significant bone loss, hosts with medical comorbidity, and often, poor soft tissues. In these situations, two stage exchange remains the gold standard to which all other interventions should be compared. With few exceptions, the published success rates for two stage procedures have been better, albeit slightly, than those published for one stage exchanges. Both static and articulating cement spacers have been used with good results. Further research is needed to better define the most effective treatment protocols, however, until further information is available, two stage exchange, with success rates of 80–90%, remains the most successful intervention for chronically infected TKA.
A “two-stage exchange” remains the gold standard for treatment of the infected THA in North America. Although there is interest in “one-stage exchange” this technique is predicated on the use of fixation of the revision implants with antibiotic loaded cement, which is not as popular in North America. Diagnosis is critical and in general consists of a screening serum ESR and CRP followed by selective aspiration if the above are abnormal and/or if the clinical history is suspicious. The aspirated fluid is sent for a synovial fluid WBC (cut-off approximately 3,000 WBC/μL), differential (cut-off 80% PMN) and culture. The basic tenets of treatment include:
Thorough debridement of all infected appearing cement and all foreign material Placement of an interval antibiotic loaded spacer (note that the addition of antibiotics to bone cement is NOT FDA approved) 4–6 g of antibiotics per pkg of cement; typically vancomycin + tobramycin Higher viscosity cement may be associated with higher elution Higher elution with combination of antibiotics Antibiotic spacers can be “articulating” or “static”. Potential advantages of an articulating spacer include greater patient comfort and an easier approach at the second stage exchange as leg length and soft tissue tension is maintained. However, these spacers are oftentimes more costly and can dislocate. May not be appropriate in cases where there is severe bone loss that cannot support partial weight bearing or if the abductors are compromised (higher risk of dislocation). The first stage is followed by approximately 6 weeks of organism specific IV antibiotics. An interdisciplinary approach with an infectious disease specialist, internal medicine and a nutritionist optimises outcomes. Our protocol then includes weekly ESR and CRP to monitor their trend. These labs are re-checked two weeks after cessation of antibiotics to ensure the trend has not changed. We have found that while the ESR and CRP are significantly lower than prior to the 1st stage, they often times DO NOT normalise and there is no specific cut-off value that predicts persistent infection. An intra-operative aspiration for synovial fluid WBC count and differential is obtained intra-operatively (cut-off values of approximately 3,000 WBC/μl and 80% PMN) and are the best tests to identify persistent infection.
Epiphysiodesis is a commonly used treatment for lower limb angular deformities. However, in recent years, distal tibial growth modulation using ‘eight plates’ or screws has emerged as an alternative treatment for paediatric foot and ankle disorders, such as CTEV. Our objective was to assess the efficacy of distal tibial modulation in correcting various paediatric foot and ankle disorders. This retrospective study analysed 205 cases of paediatric foot and ankle disorders treated between 2003 and 2022, including only cases where the eight plate or screw was fixed on the anterior surface of the distal tibia. Our aim was to measure post-operative changes in dorsiflexion, the distal tibial angle, and the tibiocalcaneal angle by examining clinical records and radiology reports.Abstract
Objectives
Methods
Little is known about the impact of cartilage defects on knee joint biomechanics. This investigation aimed to determine the gait characteristics of patients with symptomatic articular cartilage lesions of the knee. Gait analyses were performed at the Regional North-West Joint Preservation Centre. Anthropometric measurements were obtained, then 16 retroreflective markers representing the Plug-in-Gait biomechanical model were placed on pre-defined anatomical landmarks. Participants walked for two minutes at a self-selected speed on a treadmill on a level surface, then for 2 minutes downhill. A 15-camera motion-capture system recorded the data. Knee kinematics were exported into Matlab to calculate the average kinematics and spatiotemporal parameters per patient across 20 gait cycles. Depending on the normality of the data, paired t-tests or Wilcoxon ranked tests were performed to compare both knees (α = 0.05).Abstract
Objectives
Methods
In relation to regenerative therapies in osteoarthritis and cartilage repair, mesenchymal stromal cells (MSCs) have immunomodulatory functions and influence macrophage behaviour. Macrophages exist as a spectrum of pro-(M1) and anti-(M2) inflammatory phenotypic subsets. In the context of cartilage repair, we investigated MSC-macrophage crosstalk, including specifically the priming of cartilage cells by macrophages to achieve a regenerative rather than fibrotic outcome. Human monocytes were isolated from blood cones and differentiated towards M1 and M2 macrophages. Monocytes (Mo), M1 and M2 macrophages were cultured directly and indirectly (trans-well system) with human bone marrow derived MSCs. MSCs were added during M1 polarisation and separately to already induced M1 cells. Outcomes (M1/M2 markers and ligands/receptors) were evaluated using RT-qPCR and flow cytometry. Influence on chondrogenesis was assessed by applying M1 and M2 macrophage conditioned media (CM) sequentially to cartilage derived cells (recapitulating an acute injury environment). RT-qPCR was used to evaluate chondrogenic/fibrogenic gene transcription.Abstract
Objectives
Methods
Ultrasonic cutting in surgery has great potential. However, a key limitation is heat created by friction between the bone and the blade. Bone has poor thermal conductivity which hinders the dissipation of heat, causing cell death near the cut site In addition, ultrasonic vibration may create microcracks. It was hypothesised that these effects on bone would vary with the frequency and displacement of the ultrasonically powered blade. Therefore varying frequencies and displacements of the tip of the blade were studied to find the combination with fewest microcracks and lowest temperature rise at the bone-tool interface. To explore the effect of different frequencies and tip displacements of ultrasonic cutting devices on the amount of thermal and mechanical damage.Abstract
Introduction
Aim
To compare the effectiveness of phonophoresis (PH) and conventional therapeutic ultrasound (US) on the functional and pain outcomes of patients with knee osteoarthritis. We conducted an electronic search through PubMed, Cochrane Central Register of Clinical Trials (CENTRAL), Web of Science (WOS), and Scopus databases. We screened the retrieved articles to include only English full-text randomized controlled trials that examined the effect of phonophoresis versus conventional therapeutic ultrasound on patients with knee osteoarthritis. Two reviewers screened, extracted the data, and independently assessed the quality of the included articles.Abstract
Objectives
Methods
Hemi-arthroplasty (HA) as a treatment for fractured neck of femur has slightly increased since 2019 and remarkably after the COVID pandemic. The main drawback of the treatment is ongoing cartilage deterioration that may require revision to THR. This study assessed cartilage surface damage in hip HA by reproducing anatomical motion and loading conditions in a hip simulator.Abstract
BACKGROUND
OBJECTIVE
Skeletal muscle wasting is an important clinical issue following acute traumatic injury, and can delay recovery and cause permanent functional disability particularly in the elderly. However, the fundamental mechanisms involved in trauma-induced muscle wasting remain poorly defined and therapeutic interventions are limited. To characterise local and systemic mediators of skeletal muscle wasting in elderly patients following acute trauma.Abstract
Introduction
Objectives
Approximately 20% of primary and revision Total Knee Arthroplasty (TKA) patients require multiple revisions, which are associated with poor survivorship, with worsening outcomes for subsequent revisions. For revision surgery, either endoprosthetic replacements or metaphyseal sleeves can be used for the repair, however, in cases of severe defects that are deemed “too severe” for reconstruction, endoprosthetic replacement of the affected area is recommended. However, endoprosthetic replacements have been associated with high complication rates (high incidence rates of prosthetic joint infection), while metaphyseal sleeves have a more acceptable complication profile and are therefore preferred. Despite this, no guidance exists as to the maximal limit of bone loss, which is acceptable for the use of metaphyseal sleeves to ensure sufficient axial and rotational stability. Therefore, this study assessed the effect of increasing bone loss on the primary stability of the metaphyseal sleeve in the proximal tibia to determine the maximal bone loss that retains axial and rotational stability comparable to a no defect control. to determine the pattern of bone loss and the average defect size that corresponds to the clinically defined defect sizes of small, medium and large defects, a series of pre-operative x-rays of patients with who underwent revision TKA were retrospectively analysed. Ten tibiae sawbones were used for the experiment. To prepare the bones, the joint surface was resected the typical resection depth required during a primary TKA (10mm). Each tibia was secured distally in a metal pot with perpendicular screws to ensure rotational and axial fixation to the testing machine. Based on X-ray findings, a fine guide wire was placed 5mm below the cut joint surface in the most medial region of the plateau. Core drills (15mm, 25mm and 35mm) corresponding to small, medium and large defects were passed over the guide wire allowing to act at the centre point, before the bone defect was created. The test was carried out on a control specimen with no defect, and subsequently on a Sawbone with a small, medium or large defect. Sleeves were inserted using the published operative technique, by trained individual using standard instruments supplied by the manufacturers. Standard axial pull-out (0 – 10mm) force and torque (0 – 30°) tests were carried out, recording the force (N) vs. displacement (mm) curves. A circular defect pattern was identified across all defects, with the centre of the defect located 5mm below the medial tibial base plate, and as medial as possible. Unlike with large defects, small and medium sized defects reduced the pull-out force and torque at the bone-implant interface, however, these reductions were not statistically significant when compared to no bony defect.Abstract
Methods
Results
Neonatal motor development transitions from initially spontaneous to later increasingly complex voluntary movements. A delay in transitioning may indicate cerebral palsy (CP). The general movement optimality score (GMOS) evaluates infant movement variety and is used to diagnose CP, but depends on specialized physiotherapists, is time-consuming, and is subject to inter-observer differences. We hypothesised that an objective means of quantifying movements in young infants using motion tracking data may provide a more consistent early diagnosis of CP and reduce the burden on healthcare systems. This study assessed lower limb kinematic and muscle force variances during neonatal infant kicking movements, and determined that movement variances were associated with GMOS scores, and therefore CP. Electromagnetic motion tracking data (Polhemus) was collected from neonatal infants performing kicking movements (min 50° knee extension-flexion, <2 seconds) in the supine position over 7 minutes. Tracking data from lower limb anatomical landmarks (midfoot inferior, lateral malleolus, lateral knee epicondyle, ASIS, sacrum) were applied to subject-scaled musculoskeletal models (Gait2354_simbody, OpenSim). Inverse kinematics and static optimisation were applied to estimate lower limb kinematics (knee flexion, hip flexion, hip adduction) and muscle forces (quadriceps femoris, biceps femoris) for isolated kicks. Functional principal component analysis (fPCA) was carried out to reduce kicking kinematic and muscle force waveforms to PC scores capturing ‘modes’ of variance. GMOS scores (lower scores = reduced variety of movement) were collected in parallel with motion capture by a trained operator and specialised physiotherapist. Pearson's correlations were performed to assess if the standard deviation (SD) of kinematic and muscle force waveform PC scores, representing the intra-subject variance of movement or muscle activation, were associated with the GMOS scores.Abstract
Objectives
Methods
Post operative radiographs following total joint arthroplasty are requested as part of routine follow up in many institutions. These studies have a significant cost to the local departments, in terms of financial and clinic resources, however, previous research has suggested they may not alter the course of the patients treatment. The purpose of this study was to assess the significance of elective post operative radiographs on changes in management of patients who underwent total joint arthroplasty. All patients who underwent total knee arthroplasty and total hip arthroplasty at a District General Hospital from 2019 to 2020 were included. Data was collected retrospectively from medical records and radiograph requests. Alterations to clinical management based on radiographic findings were reviewed in clinic letters.Abstract
Background
Method
The medial meniscus is crescent shaped and it is wider posteriorly than anteriorly. It covers up to 60 % of the articular surface of medial tibial condyle and helps with the loading distribution in the medial compartment. Meniscal lesions occur in association with ACL tears in 60 % of the time. The posterior aspect of the menisco-capsular junction is known as the meniscal rampzone. If not addressed during surgery, it could lead to unfavourable results. Incidence of ramp lesion following ACL injuries.Abstract
Introduction
Objective
In the NHS the structure of a “regular healthcare team” is no longer the case. The NHS is facing a workforce crisis where cross-covering of ward-based health professionals is at an all-time high, this includes nurses, doctors, therapists, pharmacists and clerks. Comprehensive post-operative care documentation is essential to maintain patient safety, reduce information clarification requests, delays in rehabilitation, treatment, and investigations. The value of complete surgical registry data is emerging, and in the UK this has recently become mandated, but the completeness of post-operative care documentation is not held to the same importance, and at present there is no published standard. This project summarises a 4-stage approach, including 6 audit cycles, >400 reviewed operation notes, over a 5 year period. To deliver a sustainable change in post operative care documentation practices through quality improvement frameworks.Abstract
INTRODUCTION
OBJECTIVE
There is no specific framework for the clinical management of sports related brachial plexus injuries. Necessarily, rehabilitation is based on injury presentation and clinical diagnostics but it is unclear what the underlying evidence base to inform rehabilitative management. A systematic review of the literature was undertaken in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We applied the PEO criteria to inform our search strategy to find articles that reported the rehabilitative management of brachial plexus injuries sustained while playing contact sports. An electronic search of Medline, CINAHL, SPORTDiscus and Web of Science from inception to 3rd November 2022 was conducted. MESH terms and Boolean operators were employed. We applied an English language restriction but no other filters. Manual searches of Google Scholar and citation searching of included manuscripts were also completed. All study types were considered for inclusion provided they were published as peer-reviewed primary research articles and contained relevant information. Two investigators independently carried out the searches, screened by title, abstract and full text. Two researchers independently extracted the data from included articles. Data was cross-checked by a third researcher to ensure consistency. To assess internal validity and risk of bias, the Joanna Briggs Institute (JBI) critical appraisal tools were utilised.Abstract
Objective
Methods
Dislocation post THA confers a higher risk of re-dislocation (Kotwal et al, 2009). The dual mobility (DM) cup design (1974) was aimed at improving the stability by increasing the femoral head to neck ratio (Cuthbert et al., 2019) combining the ideas of low friction arthroplasty with increased jump distance associated with a big head arthroplasty. Understand the dislocation rates, rates of aseptic loosening, infection rate and revision rates between the 2 types of constructs to provide current and up-to date evidence.Abstract
Introduction
Aims
Intra-articular distal humerus OTA type C fractures are challenging to treat. When osteosynthesis is not feasible one can choose to do a primary arthroplasty of elbow or manage non-operatively. The indications for treatment of this fracture pattern are evolving. We present our outcomes and complications when this cohort of patients was managed with either open reduction internal fixator (ORIF), elbow arthroplasty or non-operatively.Abstract
Introduction
Objectives
