Michalis Panteli

Topical tranexamic acid in total knee replacement: A systematic review and meta-analysis

BACKGROUND To examine the safety and efficacy of topical use of tranexamic acid (TA) in total knee arthroplasty (TKA). METHODS An electronic literature search of PubMed Medline; Ovid Medline; Embase; and the Cochrane Library was performed, identifying studies published in any language from 1966 to February 2013. The studies enrolled adults undergoing a primary TKA, where topical TA was used. Inverse variance statistical method and either a fixed or random effect model, depending on the absence or presence of statistical heterogeneity were used; subgroup analysis was performed when possible. RESULTS We identified a total of seven eligible reports for analysis. Our meta-analysis indicated that when compared with the control group, topical application of TA limited significantly postoperative drain output (mean difference: -268.36ml), total blood loss (mean difference=-220.08ml), Hb drop (mean difference=-0.94g/dL) and lowered the risk of transfusion requirements (risk ratio=0.47, 95CI=0.26-0.84), without increased risk of thromboembolic events. Sub-group analysis indicated that a higher dose of topical TA (>2g) significantly reduced transfusion requirements. CONCLUSIONS Although the present meta-analysis proved a statistically significant reduction of postoperative blood loss and transfusion requirements with topical use of TA in TKA, the clinical importance of the respective estimates of effect size should be interpreted with caution. LEVEL OF EVIDENCE I, II.

Biological and molecular profile of fracture non-union tissue: current insights

Delayed bone healing and non‐union occur in approximately 10% of long bone fractures. Despite intense investigations and progress in understanding the processes governing bone healing, the specific pathophysiological characteristics of the local microenvironment leading to non‐union remain obscure. The clinical findings and radiographic features remain the two important landmarks of diagnosing non‐unions and even when the diagnosis is established there is debate on the ideal timing and mode of intervention. In an attempt to understand better the pathophysiological processes involved in the development of fracture non‐union, a number of studies have endeavoured to investigate the biological profile of tissue obtained from the non‐union site and analyse any differences or similarities of tissue obtained from different types of non‐unions. In the herein study, we present the existing evidence of the biological and molecular profile of fracture non‐union tissue.

Biomechanical rationale for implant choices in femoral neck fracture fixation in the non-elderly

Femoral neck fractures represent a relatively uncommon injury in the non-elderly population often resulting from high-energy trauma. The cornerstone of their management is anatomic reduction and stable internal fixation of the femoral neck in an attempt to salvage the femoral head. Complications including avascular necrosis of the femoral head, non-union and post-traumatic osteoarthritis are not uncommon. The clinical outcomes of these patients can be improved with good pre-operative planning, optimization of surgical procedures and introduction of new improved implants and techniques. In the herein study, we attempt to describe the biomechanical properties of the hip and compare the performance of the most commonly used devices. Experimental evidence suggests that in Pauwels type III fracture patterns a cephalomedullary nail was significantly stronger in axial loading. Moreover, in unstable basicervical patterns cannulated screws (triangular configuration) demonstrated a lower ultimate load to failure, whereas in subcapital or transervical patterns both the cannulated screws (triangular configuration) and the sliding hip screw demonstrated no compromise in fixation strength. The fracture pattern appears to be the major determinant of the ideal type of implant to be selected. For a successful outcome each patient needs to be considered on an individual basis taking into account all patient and implant related factors.

Neoplasia following use of BMPs: is there an increased risk?

Introduction: Bone morphogenetic proteins are multi-functional growth factors, which play an important role in embryonic development and cellular functions. Among several molecules in this family, BMP-2 and BMP-7 are currently being used in the clinical setting. Main clinical targets include the treatment of non-union, open fractures and spinal fusion. Their use has not been without complications, one of which might be a carcinogenic effect. Areas covered: The authors offer a comprehensive review of the existing literature on the clinical studies analysing the role of bone morphogenetic proteins (BMPs) on carcinogenesis. The authors analyse the available literature and describe potential signalling pathways that can be affected as per available experimental in vitro and in vivo models. Expert opinion: The available experimental data and clinical evidence are rather inadequate to allow any safe scientific conclusions. Clinical studies provide incomplete evidence to support the hypothesis that BMPs are carcinogenic. The available literature has several limitations including incomplete documentation, unreported data and inhered bias as a large number of trials have been funded by the industry. The need of well-structured studies is essential to address these safety concerns.

Chronic osteomyelitis: what the surgeon needs to know

Chronic osteomyelitis represents a progressive inflammatory process caused by pathogens, resulting in bone destruction and sequestrum formation. It may present with periods of quiescence of variable duration, whereas its occurrence, type, severity and prognosis is multifactorial. The ‘gold standard’ for the diagnosis of chronic osteomyelitis is the presence of positive bone cultures and histopathologic examination of the bone. Its management remains challenging to the treating physician, with a multidisciplinary approach involving radiologists, microbiologists with expertise in infectious diseases, orthopaedic surgeons and plastic surgeons. Treatment should be tailored to each patient according the severity and duration of symptoms, as well as to the clinical and radiological response to treatment. A combined antimicrobial and surgical treatment should be considered in all cases, including appropriate dead space management and subsequent reconstruction. Relapse can occur, even following an apparently successful treatment, which has a major impact on the quality of life of patients and is a substantial financial burden to any healthcare system. Cite this article EFORT Open Rev 2016;1:128–135. DOI: 10.1302/2058-5241.1.000017.

Malignant transformation in chronic osteomyelitis: recognition and principles of management.

Malignant transformation as a result of chronic osteomyelitis represents a relatively rare and late complication with a declining incidence in the modern world. For most patients, the interval between the occurrence of the original bacterial infection and the transformation to malignant degeneration is several years. The diagnosis of malignant transformation in a chronic discharging sinus requires a high index of clinical suspicion. Wound biopsies should be obtained early, especially with the onset of new clinical signs such as increased pain, a foul smell, and changes in wound drainage. Squamous cell carcinoma is the most common presenting malignancy. Definitive treatment is amputation proximal to the tumor or wide local excision, combined with adjuvant chemotherapy and radiation therapy in selected patients. Early diagnosis may sometimes allow for treatment consisting of en bloc excision and limb salvage techniques. However, the most effective treatment is prevention with definitive treatment of the osteomyelitis, including adequate débridement, wide excision of the affected area, and early reconstruction.

Can we enhance fracture vascularity: What is the evidence?

Angiogenesis is a vital component of bone healing. The formation of the new blood vessels at the fracture site restores the hypoxia and nutrient deprivation found at the early stages after fracture whilst at a later stage facilitates osteogenesis by the activity of the osteoprogenitor cells. Emerging evidence suggests that there are certain molecules and gene therapies that could promote new blood vessel formation and as a consequence enhance the local bone healing response. This article summarizes the current in vivo evidence on therapeutic approaches aiming at the augmentation of the angiogenic signalling during bone repair.

Bone Healing: The Diamond Concept

The incidence of fracture non-union has been estimated to be as high as 10 %. The treatment of fracture non-union remains challenging even for the most experienced surgeons. The presence of a poor soft tissue envelope, deformity, avascular bone edges, reduced bone stock, low-grade infection and patient related co-morbidities are some of the important contributing factors that need to be addressed. Evaluation of the complexity of the non-union and formulating the appropriate pre-operative plan and treatment modality requires good understanding of the pathogenicity of this condition and having extensive surgical experience.

The role of peptides in bone healing and regeneration: a systematic review

BackgroundBone tissue engineering and the research surrounding peptides has expanded significantly over the last few decades. Several peptides have been shown to support and stimulate the bone healing response and have been proposed as therapeutic vehicles for clinical use. The aim of this comprehensive review is to present the clinical and experimental studies analysing the potential role of peptides for bone healing and bone regeneration.MethodsA systematic review according to PRISMA guidelines was conducted. Articles presenting peptides capable of exerting an upregulatory effect on osteoprogenitor cells and bone healing were included in the study.ResultsBased on the available literature, a significant amount of experimental in vitro and in vivo evidence exists. Several peptides were found to upregulate the bone healing response in experimental models and could act as potential candidates for future clinical applications. However, from the available peptides that reached the level of clinical trials, the presented results are limited.ConclusionFurther research is desirable to shed more light into the processes governing the osteoprogenitor cellular responses. With further advances in the field of biomimetic materials and scaffolds, new treatment modalities for bone repair will emerge.

Ability of bone graft substitutes to support the osteoprogenitor cells: An in-vitro study

AIM To compare seven commercially available bone graft substitutes (BGS) in terms of these properties and without using any additional biological growth factors. METHODS Porcine osteoprogenitor cells were loaded on seven commercially available BGS and allowed to proliferate for one week followed by osteogenic induction. Staining for live/dead cells as well as scanning electron microscopy (SEM) was carried out to determine viability and cellular binding. Further outcome measures included alkaline phosphatase (ALP) assays with normalisation for DNA content to quantify osteogenic potential. Negative and positive control experiments were carried out in parallel to validate the results. RESULTS Live/dead and SEM imaging showed higher viability and attachment with β-tricalcium phosphate (β-TCP) than with other BGS (P < 0.05). The average ALP activity in nmol/mL (normalised value for DNA content in nmol/μg DNA) per sample was 657.58 (132.03) for β-TCP, 36.22 (unable to normalise) for calcium sulphate, 19.93 (11.39) for the Hydroxyapatite/Tricalcium Phosphate composite, 14.79 (18.53) for polygraft, 13.98 (8.15) for the highly porous β-Tricalcium Phosphate, 5.56 (10.0) for polymers, and 3.82 (3.8) for Hydroxyapatite. CONCLUSION Under the above experimental conditions, β-TCP was able to maintain better the viability of osteoprogenitor cells and allow proliferation and differentiation (P < 0.05).