Adipose-derived regenerative therapies for the treatment of knee osteoarthritis

Knee osteoarthritis is a degenerative condition with a significant disease burden and no disease-modifying therapy. Definitive treatment ultimately requires joint replacement. Therapies capable of regenerating cartilage could significantly reduce financial and clinical costs. The regenerative potential of mesenchymal stromal cells (MSCs) has been extensively studied in the context of knee osteoarthritis. This has yielded promising results in human studies, and is likely a product of immunomodulatory and chondroprotective biomolecules produced by MSCs in response to inflammation. Adipose-derived MSCs (ASCs) are becoming increasingly popular owing to their relative ease of isolation and high proliferative capacity. Stromal vascular fraction (SVF) and micro-fragmented adipose tissue (MFAT) are produced by the enzymatic and mechanical disruption of adipose tissue, respectively. This avoids expansion of isolated ASCs ex vivo and their composition of heterogeneous cell populations, including immune cells, may potentiate the reparative function of ASCs. In this editorial, we comment on a multicenter randomized trial regarding the efficacy of MFAT in treating knee osteoarthritis. We discuss the study's findings in the context of emerging evidence regarding adipose-derived regenerative therapies. An underlying mechanism of action of ASCs is proposed while drawing important distinctions between the properties of isolated ASCs, SVF, and MFAT.

Evaluating the Effect of Hypoxia on Human Adult Mesenchymal Stromal Cell Chondrogenesis In Vitro: A Systematic Review

Human adult mesenchymal stromal cells (MSCs) from a variety of sources may be used to repair defects in articular cartilage by inducing them into chondrogenic differentiation. The conditions in which optimal chondrogenic differentiation takes place are an area of interest in the field of tissue engineering. Chondrocytes exist in vivo in a normally hypoxic environment and thus it has been suggested that exposing MSCs to hypoxia may also contribute to a beneficial effect on their differentiation. There are two main stages in which MSCs can be exposed to hypoxia, the expansion phase when cells are cultured, and the differentiation phase when cells are induced with a chondrogenic medium. This systematic review sought to explore the effect of hypoxia at these two stages on human adult MSC chondrogenesis in vitro. A literature search was performed on PubMed, EMBASE, Medline via Ovid, and Cochrane, and 24 studies were ultimately included. The majority of these studies showed that hypoxia during the expansion phase or the differentiation phase enhances at least some markers of chondrogenic differentiation in adult MSCs. These results were not always demonstrated at the protein level and there were also conflicting reports. Studies evaluating continuous exposure to hypoxia during the expansion and differentiation phases also had mixed results. These inconsistent results can be explained by the heterogeneity of studies, including factors such as different sources of MSCs used, donor variability, level of hypoxia used in each study, time exposed to hypoxia, and differences in culture methodology.

Infrapatellar fat pad adipose-derived stem cells co-cultured with articular chondrocytes from osteoarthritis patients exhibit increased chondrogenic gene expression

Aim

The variable results in clinical trials of adipose tissue-derived stem cells (ASCs) for chondral defects may be due to the different ex vivo culture conditions of the ASCs which are implanted to treat the lesions. We sought to determine the optimal in vitro chondrocyte co-culture condition that promotes infrapatellar fat pad-derived (IFPD) ASC chondrogenic gene expression in a novel co-culture combination.

Methods

In our study, we utilized an in vitro autologous co-culture of IFPD ASCs and articular chondrocytes derived from Kellgren–Lawrence Grade III/IV osteoarthritic human knee joints at ASC-to-chondrocyte seeding log ratios of 1:1, 10:1, and 100:1. Gene expression following in vitro co-culture was quantified by RT-qPCR with a panel comprising COL1A1, COL2A1, COL10A1, L-SOX5, SOX6, SOX9, ACAN, HSPG2, and COMP for chondrogenic gene expression.

Results

The chondrogenic gene expression profiles from co-cultures were greater than would be expected from an expression profile modeled from chondrocyte and ASC-only monocultures. Additionally, chondrogenic gene expression decreased with increasing ASC-to-chondrocyte seeding ratios.

Conclusions

These findings provide insight into the mechanisms underlying clinical ASC therapies and signifies that IFPD ASCs pre-conditioned by chondrocyte co-culture may have improved chondrogenic potential for cartilage repair. This model can help further understand IFPD ASCs in chondral and osteochondral repair and the chondrogenic pathways involved.

Tendon healing is adversely affected by low-grade inflammation

BACKGROUND

Tendinopathy is common, presents with pain and activity limitation, and is associated with a high risk of recurrence of the injury. Tendinopathy usually occurs as a results of a disrupted healing response to a primary injury where cellular and molecular pathways lead to low grade chronic inflammation.

MAIN FINDINGS

There has been a renewed interest in investigating the role of Inflammation in the pathogenesis of tendinopathy, in particular during the initial phases of the condition where it may not be clinically evident. Understanding the early and late stages of tendon injury pathogenesis would help develop new and effective treatments addressed at targeting the inflammatory pathways.

CONCLUSION

This review outlines the role of low-grade Inflammation in the pathogenesis of tendinopathy, stressing the role of proinflammatory cytokines, proteolytic enzymes and growth factors, and explores how Inflammation exerts a negative influence on the process of tendon healing.

The Use of Infrapatellar Fat Pad-Derived Mesenchymal Stem Cells in Articular Cartilage Regeneration: A Review

Cartilage is frequently damaged with a limited capacity for repair. Current treatment strategies are insufficient as they form fibrocartilage as opposed to hyaline cartilage, and do not prevent the progression of degenerative changes. There is increasing interest in the use of autologous mesenchymal stem cells (MSC) for tissue regeneration. MSCs that are used to treat articular cartilage defects must not only present a robust cartilaginous production capacity, but they also must not cause morbidity at the harvest site. In addition, they should be easy to isolate from the tissue and expand in culture without terminal differentiation. The source of MSCs is one of the most important factors that may affect treatment. The infrapatellar fat pad (IPFP) acts as an important reservoir for MSC and is located in the anterior compartment of the knee joint in the extra-synovial area. The IPFP is a rich source of MSCs, and in this review, we discuss studies that demonstrate that these cells have shown many advantages over other tissues in terms of ease of isolation, expansion, and chondrogenic differentiation. Future studies in articular cartilage repair strategies and suitable extraction as well as cell culture methods will extend the therapeutical application of IPFP-derived MSCs into additional orthopedic fields, such as osteoarthritis. This review provides the latest research concerning the use of IPFP-derived MSCs in the treatment of articular cartilage damage, providing critical information for the field to grow.

Cryopreservation of Human Adipose Tissues and Adipose-Derived Stem Cells with DMSO and/or Trehalose: A Systematic Review

Adipose tissue senescence is implicated as a major player in obesity- and ageing-related disorders. There is a growing body of research studying relevant mechanisms in age-related diseases, as well as the use of adipose-derived stem cells in regenerative medicine. The cell banking of tissue by utilising cryopreservation would allow for much greater flexibility of use. Dimethyl sulfoxide (DMSO) is the most commonly used cryopreservative agent but is toxic to cells. Trehalose is a sugar synthesised by lower organisms to withstand extreme cold and drought that has been trialled as a cryopreservative agent. To examine the efficacy of trehalose in the cryopreservation of human adipose tissue, we conducted a systematic review of studies that used trehalose for the cryopreservation of human adipose tissues and adipose-derived stem cells. Thirteen articles, including fourteen studies, were included in the final review. All seven studies that examined DMSO and trehalose showed that they could be combined effectively to cryopreserve adipocytes. Although studies that compared nonpermeable trehalose with DMSO found trehalose to be inferior, studies that devised methods to deliver nonpermeable trehalose into the cell found it comparable to DMSO. Trehalose is only comparable to DMSO when methods are devised to introduce it into the cell. There is some evidence to support using trehalose instead of using no cryopreservative agent.

The Effectiveness of Anti-Nerve Growth Factor Monoclonal Antibodies in the Management of Pain in Osteoarthritis of the Hip and Knee: A PRISMA Systematic Review and Meta-Analysis

OBJECTIVE

To conduct a systematic review and meta-analysis of the efficacy of anti-nerve growth factor (NGF) monoclonal antibodies in osteoarthritis pain (hip and knee).

DESIGN

Grade the evidence for anti-NGF use.

METHODS

An interdisciplinary work group conducted a literature search for anti-NGF use in osteoarthritis. The systematic review was performed in accordance with methods described by the Cochrane collaboration. General inclusion criteria included all osteoarthritis trials studying any monoclonal anti-NGF antibody at any dose/phase. Excluded studies were those where participants received NSAIDs or analgesics other than anti-NGF antibodies. The Jadad Scale score was used to assess the quality of the included studies.

RESULTS

Thirteen studies were included in the analysis, involving 8145 participants with a diagnosis of hip and/or knee osteoarthritis. Anti-NGF antibody treatment was associated with a significant improvement in all Western Ontario and McMaster Universities Arthritis Index (WOMAC) indices when compared to placebo. These agents were not associated with a significantly increased incidence of serious adverse events but were associated with significant increases in therapy discontinuation due to adverse events or side effects (e.g., peripheral neuropathy).

CONCLUSIONS

Future randomized clinical trials are needed to characterize the overall risk-to-benefit ratio of anti-NGF antibodies in managing pain associated with OA, particularly with long-term use, in order to verify their efficacy and safety in clinical practice.

Bioactive Glass: Methods for Assessing Angiogenesis and Osteogenesis

Biomaterials are playing an increased role in the regeneration of damaged or absent bone tissue in the context of trauma, non-union, infection or congenital abnormality. Restoration of not only the physical scaffold that bone provides, but also of its homeostatic functions as a calcium store and hematopoietic organ are the gold standards of any regenerative procedure. Bioactive glasses are of interest as they can bond with the host bone and induce further both bone and blood vessel growth. The composition of the bioactive glasses can be manipulated to maximize both osteogenesis and angiogenesis, producing a 3D scaffolds that induce bone growth whilst also providing a structure that resists physiological stresses. As the primary endpoints of studies looking at bioactive glasses are very often the ability to form substantial and healthy tissues, this review will focus on the methods used to study and quantify osteogenesis and angiogenesis in bioactive glass experiments. These methods are manifold, and their accuracy is of great importance in identifying plausible future bioactive glasses for clinical use.

Use of human induced pluripotent stem cells for cartilage regeneration in vitro and within chondral defect models of knee joint cartilage in vivo: a Preferred Reporting Items for Systematic Reviews and Meta-Analyses systematic literature review

BACKGROUND AIMS

Articular cartilage has limited regenerative ability when damaged through trauma or disease. Failure to treat focal chondral lesions results in changes that inevitably progress to osteoarthritis. Osteoarthritis is a major contributor to disability globally, which results in significant medical costs and lost wages every year. Human induced pluripotent stem cells (hiPSCs) have long been considered a potential autologous therapeutic option for the treatment of focal chondral lesions. Although there are significant advantages to hiPSCs over other stem cell options, such as mesenchymal and embryonic stem cells, there are concerns regarding their ability to form bona fide cartilage and their tumorgenicity in vivo.

METHODS

The authors carried out a systematic literature review on the use of hiPSCs to produce differentiated progeny capable of producing high-quality cartilage in vitro and regenerate cartilage in osteochondral defects in vivo in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Eight studies were included in the review that used hiPSCs or their derived progeny in xenogeneic transplants in animal models to regenerate cartilage in osteochondral defects of the knee joint. The in vitro-differentiated, hiPSC-derived and in vivo defect repair ability of the hiPSC-derived progeny transplants were assessed.

RESULTS

Most studies reported the generation of high-quality cartilage-producing progeny that were able to successfully repair cartilage defects in vivo. No tumorigenicity was observed.

CONCLUSIONS

The authors conclude that hiPSCs offer a valuable source of cartilage-producing progeny that show promise as an effective cell-based therapy in treating focal chondral lesions.

P108 Anti-nerve growth factor (anti-NGF) antibodies as analgesia in the management of osteoarthritis

Background/Aims 

Osteoarthritis is a major cause of morbidity and disability. Much of this comes from joint pain, which is exacerbated by movement and exercise. Pharmacological analgesia therefore not only has the obvious benefit of alleviating pain, but in doing so, it also facilitates exercise (a pillar of conservative management). Non-steroidal anti-inflammatory drugs (NSAIDs) and opioids are currently the main analgesics used in this context. However, these agents can cause unwanted side effects and are contraindicated in some patients. We thus conducted a systematic review and meta-analysis using the Cochrane collaboration criteria to evaluate the efficacy of anti-nerve growth factor (anti-NGF) antibodies as potential alternative analgesics in osteoarthritis of the hip and/or knee. Whilst tanezumab has been studied extensively and monoclonal anti-NGF antibodies have been reviewed in other pain states, this is the first systematic review of three key anti-NGF antibodies: tanezumab, fulranumab and fasinumab in symptomatic hip and/or knee osteoarthritis.

Methods 

An interdisciplinary work group conducted a literature search across seven electronic databases for the use of anti-NGF antibodies in osteoarthritis. All hip/knee osteoarthritis studies investigating anti-NGF antibodies regardless of dose regimen or phase of trial were included. Studies in which participants received NSAIDs or analgesics other than anti-NGF antibodies, or studies in which the only intervention was the administration of anti-NGF antibodies in combination with NSAIDs or other analgesics were excluded. The Jadad Scale score was used to assess the quality of each study.

Results 

Thirteen studies involving 8,145 patients with a diagnosis of hip and/or knee osteoarthritis were analysed. Demographic information including duration of disease and Kellgren-Lawrence grades were also extracted. Anti-NGF antibodies showed significant improvements compared to placebo as rated on the Western Ontario and McMaster Universities Arthritis Index (WOMAC) scales for pain (SMD= -0.50, 95% CI -0.71 to -0.28, P < 0.00001; I2 = 88%), physical function (SMD= -0.82, 95% CI -1.09 to -0.55, P < 0.00001; I2 = 94%) and stiffness (SMD= -0.88, 95% CI -1.22 to -0.54, P < 0.00001; I2 = 95%). These agents were not associated with a significant increase in serious adverse events but were associated with a significant increase in discontinuation due to adverse events, abnormal peripheral sensations and peripheral neuropathy.

Conclusion 

Anti-NGF antibodies appear very promising with regard to alleviating osteoarthritic hip/knee pain but more studies are needed to determine the optimal dosage and the overall risk-to benefit ratio, particularly with long-term use.

Disclosure 

J. Rammanohar: None. J. Sutton: None. K. Seah: None. W.S. Khan: None. K. To: None.

Principles and guidelines in the management of ankle fractures in adults

Ankle fractures are common injuries that have many physical and psychosocial complications. As a result, it is important to be aware of how these patients present and are managed perioperatively. Detailed guidelines from NICE and the British Orthopaedic Association have been produced on this topic, including recent developments such as the decision to weight-bear early after surgery and the use of virtual fracture clinics. This article provides an overview of the key perioperative factors that need to be considered in cases of ankle fracture and the relevant clinical guidelines.

New drug, new problem: do hip fracture patients taking NOACs experience delayed surgery, longer hospital stay, or poorer outcomes?

INTRODUCTION

Neck of femur fractures are common in the comorbid, often anticoagulated, elderly. Non-vitamin K antagonist oral anticoagulants (NOACs) may affect patient outcomes. We aimed to evaluate whether hip fracture patients admitted on warfarin or NOAC therapy were at risk of operative delay, prolonged length of stay, or increased mortality.

METHODS

We collected data for 845 patients admitted to our centre between October 2014 and December 2016. Multivariable linear regression analysis was performed to test the association between warfarin and NOAC therapy on time to surgery and length of stay. Variables in the regression model were age, sex, admission AMTS, pre-fracture mobility, ASA score, fracture type, and operation type. Fisher's exact test was used to evaluate whether warfarin or NOAC therapy delayed surgery beyond 36 or 48 hours, or decreased 30-day, 6-month, or 12-month survival.

RESULTS

Time to surgery was delayed in anticoagulated patients (p = 0.028). NOAC therapy was independently associated with increased time to surgery beyond 36 hours (p = 0.001), although not beyond 48 hours (p = 0.355), whereas warfarin therapy was not associated with either. Anticoagulation did not increase length of stay (p = 0.331). Warfarin therapy significantly reduced 30-day survival (p = 0.007), but NOAC therapy did not (p = 0.244). Neither warfarin nor NOAC therapy affected further survival.

CONCLUSIONS

NOAC therapy delays time to surgery beyond the NHS England 'Best Practice Tariff' in hip fracture patients. We aim to prospectively investigate long-term outcomes. Without a NOAC antidote, policy must change to ensure time-appropriate surgery for patients on NOACs. Preoperative involvement of the haematology team is essential.

Modelling the cost-effectiveness of total knee arthroplasty: A systematic review

Objective

Osteoarthritis causes a significant healthcare burden and the number of total knee arthroplasty (TKA) procedures is predicted to increase significantly in the coming years. We conducted a systematic review to assess the scope and quality of all current TKA cost-effectiveness analysis (CEA) studies, identify trends, and identify areas for improvement.

Methods

An electronic database search of MEDLINE, Embase, the CEA registry and Scopus was used to identify all CEA studies where TKA was used with a comparator. Studies were included from January 1, 1997 to February 2, 2020. The Quality of Health Economic Analysis Studies (QHES) instrument was used to assess their quality. Thirty-three studies were included that offered both a QALY and cost calculation. The main findings, incremental-cost effectiveness ratios and other important study characteristics were then ascertained, and trends identified.

Results

Certain surgical interventions were suggested to be more cost-effective than TKA. This included unicompartmental knee arthroplasty for unicompartmental osteoarthritis, computer-assisted TKA compared to conventional TKA, and resurfacing the patella compared to no resurfacing. TKA was more cost-effective compared to non-operative management regardless of specific patient variables.

Conclusions

The analyses of the CEAs included in the study have to be interpreted with caution. Overall, certain surgical methods within TKA and alternative methods to TKA appear to be favoured for treating particular knee osteoarthritic conditions due to their suggested greater cost-effectiveness but this should be interpreted within local contexts. Our results should help guide future policy-making as healthcare associated costs continue to rise.

An overview of the key principles and guidelines in the management of pelvic fractures

Pelvic fractures are complex injuries with a range of different presentations depending on the mechanism of trauma. Due to the morbidity and mortality of pelvic fractures, patients require thorough investigation and timely management with multidisciplinary input. Various surgical and non-surgical techniques can be used to treat pelvic fractures, as well as any associated visceral injuries. Following repair, it is important to remain vigilant for postoperative complications such as infection, sexual and urinary dysfunction, chronic pain and adverse psychological health. This article summarises the relevant UK guidance and literature and presents them in a format that follows the patient’s journey. In doing so, it highlights the key perioperative factors that need to be considered in cases of pelvic fracture.

The role of the immune system in tendon healing: a systematic review

INTRODUCTION

The role of the immune system in tendon healing relies on polymorphonucleocytes, mast cells, macrophages and lymphocytes, the 'immune cells' and their cytokine production. This systematic review reports how the immune system affects tendon healing.

SOURCES OF DATA

We registered our protocol (registration number: CRD42019141838). After searching PubMed, Embase and Cochrane Library databases, we included studies of any level of evidence published in peer-reviewed journals reporting clinical or preclinical results. The PRISMA guidelines were applied, and risk of bias and the methodological quality of the included studies were assessed. We excluded all the articles with high risk of bias and/or low quality after the assessment. We included 62 articles assessed as medium or high quality.

AREAS OF AGREEMENT

Macrophages are major actors in the promotion of proper wound healing as well as the resolution of inflammation in response to pathogenic challenge or tissue damage. The immune cells secrete cytokines involving both pro-inflammatory and anti-inflammatory factors which could affect both healing and macrophage polarization.

AREAS OF CONTROVERSY

The role of lymphocytes, mast cells and polymorphonucleocytes is still inconclusive.

GROWING POINTS

The immune system is a major actor in the complex mechanism behind the healing response occurring in tendons after an injury. A dysregulation of the immune response can ultimately lead to a failed healing response.

AREAS TIMELY FOR DEVELOPING RESEARCH

Further studies are needed to shed light on therapeutic targets to improve tendon healing and in managing new way to balance immune response.

Evaluating the Effect of Non-cellular Bioactive Glass-Containing Scaffolds on Osteogenesis and Angiogenesis in in vivo Animal Bone Defect Models

The use of bone scaffolds to replace injured or diseased bone has many advantages over the currently used autologous and allogeneic options in clinical practice. This systematic review evaluates the current evidence for non-cellular scaffolds containing bioactive glass on osteogenesis and angiogenesis in animal bone defect models. Studies that reported results of osteogenesis via micro-CT and results of angiogenesis via Microfil perfusion or immunohistochemistry were included in the review. A literature search of PubMed, EMBASE and Scopus was carried out in November 2019 from which nine studies met the inclusion and exclusion criteria. Despite the significant heterogeneity in the composition of the scaffolds used in each study, it could be concluded that scaffolds containing bioactive glass improve bone regeneration in these models, both by osteogenic and angiogenic measures. Incorporation of additional elements into the glass network, using additives, and using biochemical factors generally had a beneficial effect. Comparing the different compositions of non-cellular bioactive glass containing scaffolds is however difficult due to the heterogeneity in bioactive glass compositions, fabrication methods and biochemical additives used.

Human umbilical cord derived mesenchymal stem cells in peripheral nerve regeneration

BACKGROUND

Peripheral nerve injury can occur as a result of trauma or disease and carries significant morbidity including sensory and motor loss. The body has limited ability for nerve regeneration and functional recovery. Left untreated, nerve lesions can cause lifelong disability. Traditional treatment options such as neurorrhaphy and neurolysis have high failure rates. Surgical reconstruction with autograft carries donor site morbidity and often provide suboptimal results. Mesenchymal stem cells (MSCs) are known to have promising regenerative potential and have gained attention as a treatment option for nerve lesions. It is however, unclear whether it can be effectively used for nerve regeneration.

AIM

To evaluate the evidence for the use of human umbilical cord derived MSCs (UCMSCs) in peripheral nerve regeneration.

METHODS

We carried out a systematic literature review in accordance with the PRISMA protocol. A literature search was performed from conception to September 2019 using PubMed, EMBASE and Web of Science. The results of eligible studies were appraised. A risk of bias analysis was carried out using Cochrane’s RoB 2.0 tool.

RESULTS

Fourteen studies were included in this review. A total of 279 subjects, including both human and animal were treated with UCMSCs. Four studies obtained UCMSCs from a third-party source and the remainder were harvested by the investigators. Out of the 14 studies, thirteen conducted xenogenic transplantation into nerve injury models. All studies reported significant improvement in nerve regeneration in the UCMSC treated groups compared with the various different controls and untreated groups.

CONCLUSION

The evidence summarised in this PRISMA systematic review of in vivo studies supports the notion that human UCMSC transplantation is an effective treatment option for peripheral nerve injury.

Important perioperative factors, guidelines and outcomes in the management of hip fracture

Hip fractures are common injuries in the elderly and are associated with significant morbidity and mortality. There are multiple perioperative factors that must be considered when managing these patients. These include analgesia, timing of surgery, choice of operation, type of anaesthesia, postoperative complications and comorbidities. Guidelines from The National Institute for Health and Care Excellence and the National Hip Fracture Database have been updated to reflect many of the above, but the importance of psychosocial factors is still emerging. This article focuses on the evidence for the key perioperative factors in hip fracture management and the tools available to predict hip fracture outcome.

Tendon healing in presence of chronic low-level inflammation: a systematic review

BACKGROUND

Tendinopathy is a common musculoskeletal condition affecting subjects regardless of their activity level. Multiple inflammatory molecules found in ex vivo samples of human tendons are related to the initiation or progression of tendinopathy. Their role in tendon healing is the subject of this review.

SOURCES OF DATA

An extensive review of current literature was conducted using PubMed, Embase and Cochrane Library using the term 'tendon', as well as some common terms of tendon conditions such as 'tendon injury OR (tendon damage) OR tendonitis OR tendinopathy OR (chronic tendonitis) OR tendinosis OR (chronic tendinopathy) OR enthesitis' AND 'healing' AND '(inflammation OR immune response)' as either key words or MeSH terms.

AREAS OF AGREEMENT

An environment characterized by a low level of chronic inflammation, together with increased expression of inflammatory cytokines and growth factors, may influence the physiological tendon healing response after treatment.

AREAS OF CONTROVERSY

Most studies on this topic exhibited limited scientific translational value because of their heterogeneity. The evidence associated with preclinical studies is limited.

GROWING POINTS

The role of inflammation in tendon healing is still unclear, though it seems to affect the overall outcome. A thorough understanding of the biochemical mediators of healing and their pathway of pain could be used to target tendinopathy and possibly guide its management.

AREAS TIMELY FOR DEVELOPING RESEARCH

We require further studies with improved designs to effectively evaluate the pathogenesis and progression of tendinopathy to identify cellular and molecular targets to improve outcomes.

Single-Stage Revision Surgery in Infected Total Knee Arthroplasty: A PRISMA Systematic Review

Periprosthetic joint infection in total knee arthroplasty is a significant complication that is a common reason for revision surgery. The current standard of care is two-stage revision surgery. There is however increasing evidence to support the use of single-stage revision surgery. We conducted a PRISMA systematic review of the current evidence on the use of single-stage revision for infected total knee arthroplasty. Four databases (PubMed, Embase, Science Direct, and Cochrane Library) were systematically screened for eligible studies. The risk bias of each study was identified using ROBINS-I tool, and the quality of evidence was assessed using the GRADE criteria. Sixteen articles were retained after applying the inclusion and exclusion criteria that evaluated 3645 knee single-stage revision surgeries. Our review reveals satisfactory outcomes for single-stage revision in the management of infected total knee arthroplasty. The reinfection rates in the studies included in our review varied however the majority reported low reinfection rates and good functional outcomes. Although strict patient selection criteria have yielded successful results, good results were also reported when these criteria were not applied. The greater use of risk factors in identifying patients likely to have a successful outcome needs to be balanced with the practical benefits of performing a single stage procedure in higher risk patients. Future large clinical randomized control trials are required to confirm our results.

Are the Biological and Biomechanical Properties of Meniscal Scaffolds Reflected in Clinical Practice? A Systematic Review of the Literature

The aim of this PRISMA review was to assess whether the CMI and Actifit scaffolds, when used in clinical practice, improve clinical outcomes and demonstrate the ideal biological and biomechanical properties of scaffolds: being chondroprotective, porous, resorbable, able to mature and promote regeneration of tissue. This was done by only including studies that assessed clinical outcome and used a scale to assess both integrity of the scaffold and its effects on articular cartilage via MRI. A search was performed on PubMed, EMBASE, Scopus and clinicaltrials.gov. 2457 articles were screened, from which eight studies were selected: four used Actifit, three used CMI and one compared the two. All studies reported significant improvement in at least one clinical outcome compared to baseline. Some studies suggested that the scaffolds appeared to show porosity, mature, resorb and/or have possible chondroprotective effects, as assessed by MRI. The evidence for clinical translation is limited by differences in study methodology and small sample sizes, but is promising in terms of improving clinical outcomes in the short to mid-term. Higher level evidence, with MRI and histological evaluation of the scaffold and articular cartilage, is now needed to further determine whether these scaffolds exhibit these useful properties.

Preclinical Studies on Biomaterial Scaffold use in Knee Ligament Regeneration: A Systematic Review

BACKGROUND

Knee joint trauma may result in damage of the intra-articular ligaments, with rupture of the anterior cruciate ligament (ACL) a common and troublesome injury due to poor capabilities for spontaneous regeneration. Autograft and allograft surgical reconstructions are the mainstay of treatment, but have associated risks of failure, therefore tissue-engineering techniques aiming to regenerate the native ACL are being researched as a potential alternative treatment.

OBJECTIVES

This article aims to review the current evidence produced by ex vivo and in vivo studies investigating biomaterial scaffolding and mesenchymal stem cell (MSC) techniques in orthopaedic tissue engineering of ACL injuries.

METHODS

Databases searched were Ovid MEDLINE, Cochrane Library, Embase, Elsevier Scopus, Web of Science and NCBI PubMed, with search terms 'ligament', 'scaffold', 'mesenchymal stem cell' and 'tissue engineering'.

RESULTS

1132 articles were identified, with 19 articles suitable for review inclusion. Of the eligible studies, 10 used biologic scaffold material, 6 used synthetic constructs, and hybrid scaffolds were employed in the remaining 3 studies.

CONCLUSIONS

A large amount of preclinical evidence for viability of MSC seeded biomaterial scaffolds in ACL regeneration exists. Studies show that with stimulation, MSCs adhere and proliferate well on various scaffold materials ranging from silk to engineered polymers. Hybrid scaffolds are particularly promising, and with further research, the best features from strong natural substances such as silk, and biologically inert synthetic materials could be combined. Currently, there are few plans to begin human clinical trials, but preclinical studies are moving into larger animal models.

The Influence of Ageing and Gender in Musculoskeletal Stem Cell

BACKGROUND

Multipotent Mesenchymal Stromal Cells (MSCs) are the most common type of stem cell used in the regeneration of skeletal tissue. These cells have multipotent, angiogenic, paracrine, anti-fibrotic and immunological properties. They are readily available, easily isolated and have many therapeutic applications. The ageing population is on the increase and with this comes an upsurge in medical conditions that may benefit from novel stem cell-based therapies to treat ageingassociated diseases. Given that autologous implantations have shown to be beneficial in these targeted therapies, questions are raised regarding the effect of ageing and gender on the efficacy of stem cells.

OBJECTIVE

In this review, we look at the ageing process and look at the effects of ageing and gender on the characterization, proliferation and differentiation of mesenchymal stem cells. We also discuss future therapeutic strategies that may be used to overcome these effects and cell senescence.

CONCLUSION

Advancements in modern technology and experimental techniques have provided an insight into how ageing affects properties of MSCs. However, it is evident that further work needs to be conducted due to many mixed reviews and conflicting data. Given that the human life expectancy is expected to increase the topic of cell ageing and therapeutic applications will remain a hot topic in years to come.

Evaluating the Current Literature on Treatments Containing Adipose-Derived Stem Cells for Osteoarthritis: a Progress Update

PURPOSE OF REVIEW

Recent studies have investigated the effect of treatments containing adipose-derived mesenchymal stem cells (ADMSCs) on human osteoarthritis. These have mostly used biologic adjuvants which may influence results. Thus, the purpose of this systematic review is to evaluate the current literature on these treatments when used in isolation.

RECENT FINDINGS

Five studies in this review used cultured ADMSCs, while four studies used stromal vascular fraction and three used micro-fragmented adipose tissue to deliver ADMSCs. No studies reported serious treatment-related adverse effects and all reported improvements in clinical measures for at least one dose. This was not necessarily reflected in imaging evaluations nor were improvements always maintained. Current low-level evidence is limited due to variability in study methodology but indicates that treatments containing ADMSCs, when used in isolation, are safe and have the potential to reduce pain and improve function. Randomized controlled trials are now needed.

Clinical Studies Using Biological and Synthetic Materials for Meniscus Replacement

Meniscal injury is a common problem among sportsmen and increasingly seen in the older and more active population. The traditional treatment options include a partial meniscectomy, which provides good mechanical and pain relief to the patient. However, the focus of treatment is shifting towards repairing meniscal tears where possible and replacement of the lost meniscal tissue where appropriate. Replacement can be total or partial. Total meniscal replacement using an allograft, is usually reserved for young patients, who meet certain criteria and who have undergone several subtotal meniscectomies or a single stage total meniscectomy and are still symptomatic. Partial meniscal replacement can be utilized in conjunction with a partial meniscectomy to fill the resulting space left by the resection. Collagen based implants and synthetic scaffolds have entered the European market but have demonstrated mixed results in clinical trials. Tissue engineering to create an implant that mimics the biomechanical properties holds much potential for future research.

Knee Ligament Injury and the Clinical Application of Tissue Engineering Techniques: A Systematic Review

BACKGROUND

The incidence of knee ligament injury is increasing and represents a significant cost to healthcare providers. Current interventions include tissue grafts, suture repair and non-surgical management. These techniques have demonstrated good patient outcomes but have been associated graft rejection, infection, long term immobilization and reduced joint function. The limitations of traditional management strategies have prompted research into tissue engineering of knee ligaments.

OBJECTIVE

This paper aims to evaluate whether tissue engineering of knee ligaments offers a viable alternative in the clinical management of knee ligament injuries. A search of existing literature was performed using OVID Medline, Embase, AMED, PubMed and Google Scholar, and a manual review of citations identified within these papers.

RESULTS

Silk, polymer and extracellular matrix based scaffolds can all improve graft healing and collagen production. Fibroblasts and stem cells demonstrate compatibility with scaffolds, and have been shown to increase organized collagen production. These effects can be augmented using growth factors and extracellular matrix derivatives. Animal studies have shown tissue engineered ligaments can provide the biomechanical characteristics required for effective treatment of knee ligament injuries.

CONCLUSION

There is a growing clinical demand for a tissue engineered alternative to traditional management strategies. Currently, there is limited consensus regarding material selection for use in tissue engineered ligaments. Further research is required to optimize tissue engineered ligament production before clinical application. Controlled clinical trials comparing the use of tissue engineered ligaments and traditional management in patients with knee ligament injury could determine whether they can provide a cost-effective alternative.

Assessment of Range of Movement, Pain and Disability Following a Whiplash Injury

Background:

Whiplash has been suggested to cause chronic symptoms and long term disability. This study was designed to assess long term function after whiplash injury.

Material & Methods:

A random sample of patients in the outpatient clinic was interviewed, questionnaire completed and clinical examination performed. Assessment was made of passive cervical range of movement and Visual Analogue Scale pain scores. One hundred and sixty-four patients were divided into four different groups including patients with no whiplash injury but long-standing neck pain (Group A), previous symptomatic whiplash injury and long-standing neck pain (Group B), previous symptomatic whiplash injury and no neck symptoms (Group C), and a control group of patients with no history of whiplash injury or neck symptoms (Group D).

Results:

Data was analyzed by performing an Independent samples t-test and ANOVA, with level of significance taken as p<0.05. Comparing the four groups using a one-way ANOVA showed a significant difference between the groups (p<0.001). There were significant differences when comparing mean ranges of movement between Group A and Group D, and between Group B and Group D. There was no significant difference between Group C and Group D. similar differences were also seen in the pain scores.

Conclusion:

We conclude that osteoarthritis in the cervical spine, and whiplash injury with chronic problems cause a significantly decreased cervical range of movement with a higher pain score. Patients with shorter duration of whiplash symptoms appear to do better in the long-term.

Systematic review on the use of autologous matrix-induced chondrogenesis for the repair of articular cartilage defects in patients

AIM

To systematically review the results of studies looking at autologous matrix-induced chondrogenesis (AMIC) in humans.

METHODS

A literature search was performed, adhering to the PRISMA guidelines, to review any studies using such techniques in humans. Our initial search retrieved 297 articles listed on MEDLINE, Google Scholar, CINHal and EMBASE. From these studies, 15 studies meeting the eligibility criteria were selected and formed the basis of our systematic review.

RESULTS

The study designs, surgical techniques and outcome measures varied between the studies. Although all studies reported improvements in patient outcome measures, this was not necessarily correlated with magnetic resonance imaging findings. Although there were many additional procedures performed, when AMIC was performed in isolation, the results tended to peak at 24 mo before declining.

CONCLUSION

Although short-term studies suggest improved patient reported outcomes with a variety of scaffolds, surgical techniques and rehabilitation regimes, the literature remains equivocal on whether the defect size and location, and patient factors affect the outcome. Patient benefit appears to be maintained in the short-to-medium term but more high level studies with extensive and robust validated outcome measures should be conducted to evaluate the medium- and long-term effect of the AMIC procedure.

A Retrospective Study Comparing Crossed and Lateral Wire Configurations in Paediatric Supracondylar Fractures

Background:

Supracondylar fractures are common in children and are associated with significant morbidity.

The purpose of our study was to assess and compare the clinical and radiological outcome of management of supracondylar fractures by both wire configurations, along with identifying factors that predispose to complications.

Materials & Methods:

We retrospectively reviewed all paediatric cases admitted with a supracondylar fracture over a five year period. We reviewed case notes, theatre records and radiographs to determine the age of the patient, classification of fracture, treatment method, delay to theatre, duration of surgery, wire configuration, Baumann´s angle, radiocapitellar alignment, anterior humeral alignment and complications.

Results:

During the five year period we admitted 132 patients and complete notes were available for 123 patients for analyses. For all the patients managed with wire stabilisation 23% developed complications, including 13% with significant complications including nerve injuries and fracture displacements. All five nerve injuries had crossed wires, whereas all for fracture displacements had lateral wires. Baumann´s angle was 76.7 degrees in the group with no complication and 72.2 degrees in the significant complication group (p=0.02). Radiocapitellar line and anterior humeral line were not satisfactory in 5% and 15% of the group with no complications, and 17% and 33% of the group with significant complications.

Conclusion:

We found more complications in lateral pinning configurations, although all nerve injuries were in patients with crossed wire configurations. The factors we believe are associated with a higher likelihood of complications are inadequate post-operative radiological appearance.

Plaster of Paris-Short History of Casting and Injured Limb Immobilzation

Various materials have been used since ancient times to help immobilise fractures. In this review, we discuss the history and developments of these materials as well as plaster of Paris. There has been a recent trend away from non-operative management of fractures, and skills in the use of plaster of Paris are declining. For the successful treatment of patients, it is important to appreciate how plaster works, how it should be used, and what can go wrong. In this review, we also discuss principles of applications and complications of plaster of Paris.

Acetic Acid as Part of a Debridement Protocol During Revision Total Knee Arthroplasty

BACKGROUND

Thorough debridement is mandatory in revision for infected total knee arthroplasties (TKA). We investigated a novel adjuvant chemical debridement strategy using acetic acid (AA) that seeks to create a hostile environment for microorganisms. We report the first orthopedic in vivo series using an AA soak in infected TKAs. We also investigated the in vitro efficacy of AA against bacteria isolated from these knees.

METHODS

Twenty-three patients with infected TKA were treated with a standard debridement protocol and chemical debridement with a 20-minute AA soak. In parallel, bacteria from infected TKAs were cultured for in vitro susceptibility testing with AA solutions of different concentrations to understand its potential mechanism of action.

RESULTS

Intraoperatively, there were no physiological responses during the AA soak or on release of the tourniquet. Postoperatively, there was no increase in analgesic requirements or wound or soft-tissue complications. Clinical follow-up continued for 24 months to monitor recurrent infection. In vitro, zones of inhibition were formed on less than 40% of the organisms, demonstrating that AA was not directly bactericidal against the majority of the isolates. However, when cultured in a bacterial suspension, AA completely inhibited the growth of the isolates at concentrations as low as 0.19% vol/vol.

CONCLUSION

This study has shown that the use of 3% AA soak, as part of a debridement protocol is safe in patients. While the exact mechanism of action is yet to be determined, AA concentrations as low as 0.19% vol/vol in vitro are sufficient to completely inhibit bacterial growth.

Outcomes of Locking Plates in Proximal Humeral Fractures: A Systematic Review

A systematic review of the clinical and radiological outcomes of locking plates in proximal humeral fractures in the current English literature was performed using Medline, CINAHL, AMED and EMBASE electronic databases to July 2009 via Ovid. There were 1266 proximal humeral fractures included in the review. The mean age of the patients was 61.7 years and there were 70.3% women. Based on the Neer classification, the review included 27% two-part, 39.5% three-part and 23.6% four-part fractures. At final follow-up, the Constant score was in the range 59 to 80, and the Disabilities of the Arm, Shoulder and Hand scores were in the range 15.2 to 51.8. The most frequent postoperative complication described was intra-articular screw perforation in 8.5% of fractures. Other complications included avascular necrosis (5.1%), subacromial impingement (3.1%), loss of reduction (3.7%) and implant failure (3.15%). Unplanned secondary surgical procedures were undertaken in 14.2% of cases. This systematic review has demonstrated that locking plate systems are suitable for stabilizing proximal humeral fractures. The current evidence base presents a number of methodological weaknesses and randomized controlled trials at independent centres reporting long-term results are required to compare locking plate systems with alternative fixation techniques used in the treatment of proximal humeral fractures.

Mechanical Stimulation Protocols of Human Derived Cells in Articular Cartilage Tissue Engineering - A Systematic Review

Mechanical stimulation is a key factor in articular cartilage generation and maintenance. Bioreactor systems have been designed and built in order to deliver specific types of mechanical stimulation. The focus has been twofold, applying a type of preconditioning in order to stimulate cell differentiation, and to simulate in vivo conditions in order to gain further insight into how cells respond to different stimulatory patterns. Due to the complex forces at work within joints, it is difficult to simulate mechanical conditions using a bioreactor. The aim of this review is to gain a deeper understanding of the complexities of mechanical stimulation protocols by comparing those employed in bioreactors in the context of tissue engineering for articular cartilage, and to consider their effects on cultured cells. Allied and Complementary Medicine 1985 to 2016, Ovid MEDLINE[R] 1946 to 2016, and Embase 1974 to 2016 were searched using key terms. Results were subject to inclusion and exclusion criteria, key findings summarised into a table and subsequently discussed. Based on this review it is overwhelmingly clear that mechanical stimulation leads to increased chondrogenic properties in the context of bioreactor articular cartilage tissue engineering using human cells. However, given the variability and lack of controlled factors between research articles, results are difficult to compare, and a standardised method of evaluating stimulation protocols proved challenging. With improved standardisation in mechanical stimulation protocol reporting, bioreactor design and building processes, along with a better understanding of joint behaviours, we hope to perform a meta-analysis on stimulation protocols and methods.

The Role of Bioreactors in Ligament and Tendon Tissue Engineering

Bioreactors are pivotal to the emerging field of tissue engineering. The formation of neotissue from pluripotent cell lineages potentially offers a source of tissue for clinical use without the significant donor site morbidity associated with many contemporary surgical reconstructive procedures. Modern bioreactor design is becoming increasingly complex to provide a both an expandable source of readily available pluripotent cells and to facilitate their controlled differentiation into a clinically applicable ligament or tendon like neotissue. This review presents the need for such a method, challenges in the processes to engineer neotissue and the current designs and results of modern bioreactors in the pursuit of engineered tendon and ligament.

Outcome of surgery for chronic patellar tendinopathy: A systematic review

There is no consensus on how to best surgically treat chronic patellar tendinopathy. This systematic review investigates the surgical treatment for chronic patellar tendinopathy, and the outcomes. A database search was performed to identify all relevant articles, to which exclusion criteria were then applied. Data was extracted from 24 studies, and the outcomes were then systematically reviewed. The results showed that the success rate of surgery for patellar tendinopathy is generally over 77%. Return to sports rates are better for proximal tendon patients who undergo bony procedures. Patients return to sports faster if they undergo arthroscopic procedures, and fewer complications are described. Studies that did not involve any procedure on the proximal tendon did not produce a different result to studies where the tendon was operated on. We found no effect of post-operative immobilisation on outcome. Based on the included studies, surgery gives satisfactory results in the treatment of patellar tendinopathy. There is a lack of high-quality evidence on the effects of surgery and post-operative rehabilitation regime on chronic patellar tendinopathy, as well as lack of objective outcome measures.

Biomaterials and Fabrication to Optimise Scaffold Properties for Musculoskeletal Tissue Engineering

Tissue engineering has emerged as a promising scientific field potentially yielding in vitro developed tissue to replace degenerative or injured tissues in vivo, thus avoiding the donor site morbidity associated with reconstructive surgery. Integral to the process is the role of scaffolds and the biomaterials used to form them. This review explores the concept of scaffold based tissue engineering and design considerations. The scaffold needs to have certain mechanical and architectural properties, it needs to be biocompatible and biodegradable, and allow combination with bioactive molecules. We also discuss scaffolding techniques, different biomaterial options and fabrication technologies, and future areas of development.

Tibial Crest Osteotomy in Extensile Knee Exposure-A Modified, Low-Energy, Suture Technique

BACKGROUND

Tibial crest osteotomy is an established extensile knee approach. Complications include mal-union, non-union, and fixation problems.We have designed a technique aimed at reducing complications through the principles of low-energy osteotomy and suture repair.

METHODS

We reviewed our clinical and radiological results in 159 consecutive patients 181 osteotomies with a mean age of 66 years, and an average follow up of 22 months.

RESULTS

Union occurred in all osteotomies (100%) at a mean period of 11 weeks. Proximal migration averaging 11.5 mm occurred in 6 osteotomies (3%). Crest fragmentation occurred in 11 osteotomies (6%), with all cases resulting in uncomplicated union. No extensor mechanism failure or complications related to the suture material occurred.

CONCLUSION

We conclude that this technique results in satisfactory outcomes whilst avoiding hardware-related problems.

Biomaterials and Fabrication to Optimise Scaffold Properties for Musculoskeletal Tissue Engineering

Tissue engineering has emerged as a promising scientific field potentially yielding in vitro developed tissue to replace degenerative or injured tissues in vivo, thus avoiding the donor site morbidity associated with reconstructive surgery. Integral to the process is the role of scaffolds and the biomaterials used to form them. This review explores the concept of scaffold based tissue engineering and design considerations. The scaffold needs to have certain mechanical and architectural properties, it needs to be biocompatible and biodegradable, and allow combination with bioactive molecules. We also discuss scaffolding techniques, different biomaterial options and fabrication technologies, and future areas of development.

Impact of Weekend Physiotherapy Service on the Cost Effectiveness of Elective Orthopaedic Hip and Knee Arthroplasty

We performed a prospective correlational study to evaluate the efficiency and cost effectiveness of weekend physiotherapy in accelerating rehabilitation, reducing hospital stay as well as hospital costs for joint arthroplasty patients in a busy Scottish district general hospital. Patients that underwent elective hip (470) and knee (321) arthroplasty were analysed over a 12 month period. A four month period with weekend physiotherapy provision was arranged to ascertain its effectiveness on the length of stay and the achievement of set physiotherapy milestones. Data collected included length of stay and progression in a defined set of physiotherapy milestones. The relationship between time to discharge, mobilisation with sticks, straight leg raise, 90º knee flexion and cost effectiveness of service were used to determine the correlation, and analysis of the interactions of these factors separately. Our Outcome data demonstrate a statistical significance for the time to mobilisation with two sticks for hip (p=0.0030) and knee (p= 0.0037) arthroplasty patients. There was a trend towards earlier discharge times for all patients receiving weekend physiotherapy, but this was not statistically significant. We conclude that the provision of a continuous programme of weekend physiotherapy for all arthroplasty patients has the potential benefit of a quicker rehabilitation that would results in a cost saving.

First Metatarsalphalangeal Joint Arthrodesis: A Retrospective Comparison of Two Methods of Fixation

First metatarsalphalangeal joint arthrodesis is a well established and successful treatment; however there still remains controversy over the best choice of construct. We performed a retrospective study of patients undergoing first metatarsalphalangeal fusion over eighteen months (n=52) using either dorsal non-locking plate with additional compression lag screw fixation or dorsal non-locking plate alone. We found when assessing clinical criteria, patients with dorsal non-locking plates and additional compression lag screw fixation had a significantly higher rate of fusion (100% vs 77.8%), significantly higher rate of fusion within the first two months (55.6% vs 83.3%), significantly earlier time to fusion (52.2 days vs 75.6 days), and significantly lower rate of non-union (0% vs 22.2%). When blindly assessing radiographic criteria, the patients treated with the plate and compression screw had a significantly higher rate of fusion and lower rate of non-union (0% vs 33%). There was no statistically significant difference between the frequencies of complications in the groups. We believe that the interfragmentary compression is a crucial factor in achieving good union rates and recommend the use of non-locking pre-contoured plating with additional interfragmentary compression screw as the fixation method of choice for these procedures.

Single Stage Knee Arthroplasty Revision Surgery: A Systematic Review of the Literature

Total Knee Arthroplasty is an increasingly common procedure and revision surgery, particularly for infection, is associated with significant morbidity and healthcare costs. The current gold standard is a two stage revision procedure but single stage revision is increasingly being used in some departments to improve patient outcomes. We conducted a systematic review of the literature to determine the up-to-date evidence underlying the use of a single stage knee approach in revision surgery. A total of 12 studies were included in this review amounting to 433 revision surgeries. This is the largest review of single stage knee revision surgery. The procedures described were heterogenous and included the 'two-in-one' technique as well as other single stage revision procedures. There were also differences in implants and antibiotic regimens. The mean re-infection rates described in 10 studies was 9.4% (range 0-19.2%) after a mean follow-up of 40.3 months (range 7-180 months). The re-infection rates in the studies published over the last 30 years are falling, and this is not accounted for by any significant change in duration of follow-up during this period. The outcome scores varied, but patients generally showed an improvement. The Knee Society Score and the Oxford Knee Score were the most commonly used in five and three studies respectively. We conclude that the current evidence for single stage revision is variable and there is a lack of good quality evidence to address whether single stage revisions is thorough enough to eradicate deep infection and is able to restore adequate function. There is a need for larger prospective studies with standardised procedures and protocol, and with adequate follow-up. Till then, patients considered for a single stage approach should be thoroughly assessed and the surgery should be performed by a senior surgeon with experience in single stage knee revisions.

Current Evidence for the Use of Laminar Flow in Reducing Infection Rates in Total Joint Arthroplasty

Since the introduction of laminar air flow in orthopaedic theatres by Sir John Charnley, it has widely become accepted as the standard during orthopaedic procedures such as joint arthroplasty. We present a review of available current literature for the use of laminar flow operating theatre ventilation during total joint arthroplasty and examines the effectiveness of laminar flow ventilated operating theatres in preventing post-operative wound infection. Results of our findings suggest that while bacterial and air particulate is reduced by laminar air flow systems, there is no conclusive effect on the reduction of post-operative wound infections following total joint arthroplasty. We conclude that a combination of strict aseptic technique, prophylactic antibiotics and good anaesthetic control during surgery remains crucial to reduce post-operative surgical infections.

A Literature Review of Total Hip Arthroplasty in Patients with Ankylosing Spondylitis: Perioperative Considerations and Outcome

Ankylosing spondylitis is a spondyloarthropathy affecting the sacro-iliac joints with subsequent progression to the spine and the hip joints. The hip joints are affected by synovitis, enthesial inflammation, involvement of medullary bone, progressive degeneration and secondary osteoarthritis. Clinical presentation is usually in the form of pain and stiffness progressing to disabling fixed flexion contractures and in some instances, complete ankylosis. Hip arthroplasty should be considered for hip pain, postural and functional disability, or pain in adjacent joints due to hip stiffness. We conducted a literature review to determine peri-operative considerations and outcome in ankylosing spondylitis patients undergoing hip arthroplasty. In this review, we have discussed pre-operative surgical planning, thromboprophylaxis, anaesthetic considerations and heterotopic ossification. Outcomes of arthroplasty include range of movement, pain relief, survivorship and complications.