Reconstructive surgery after distal fibular resection due to bone tumors: a technical report on surgical strategies and results from the PROSPERO international register of systematic reviews.

Purpose: Primary bone tumors of the fibula are rare. Distal fibular resection has a significant impact on ankle biomechanics and gait, possibly leading to complications such as ankle instability, valgus deformity, and degenerative changes. Question: Is there a need for reconstructive surgery after distal fibular resection, and what reconstructive procedures are available? Materials and methods: The review is registered with the PROSPERO International Register of Systematic Reviews. Inclusion criteria consisted of all levels of evidence, human studies, patients of all ages and genders, publication in English, and resection of the distal portion of the fibula due to tumor pathology. The reviewers defined four different categories of interest by method of treatment. Additional articles of interest during full-text review were also added. Results: The initial search resulted with a total of 2958 records. After screening, a total of 50 articles were included in the study. Articles were divided into 'No reconstruction', 'Soft tissue reconstruction', 'Bone and soft tissue reconstruction', and 'Arthrodesis, arthroplasty or other reconstruction options' groups. Conclusion: Limb salvage surgery should be followed by reconstruction in order to avoid complications. Soft tissue reconstructions should always be considered to stabilize the joint after fibular resection. Bone reconstruction with reversed vascularized fibula is the preferred technique in young patients and in cases of bone defects more than 3 cm, while arthrodesis should be considered in adult patients. Whenever possible for oncologic reason, if a residual peroneal malleolus could be preserved, we prefer augmentation with a sliding ipsilateral fibular graft.

Modern treatment of unicameral and aneurysmatic bone cysts.

The best treatment of unicameral bone cyst and aneurismatic bone cyst (ABC) is debated in the literature. For simple bone cysts, multiple treatments were proposed from observation only to open curettage. The historical treatment with intraosseous injection of methylprednisolone acetate into the bone cysts nowadays is reduced due to the morbidity of multiple injections and the risk of multiple pathologic fractures until the healing. Different types of treatments for ABC are reported, including surgery, percutaneous treatments, and medical treatments; however, there is currently no consensus on the best approach. The association of curettage, bone graft, and elastic stable intramedullary nail (ESIN) had a success rate of over 85%. Decompressing the cyst wall is more critical for increasing the healing rate than the type of graft used to fill the cavity. In ABC, sclerotherapy offers the advantages of lower invasiveness and morbidity, associated with better functional scores and faster return to full weight-bearing. Moreover, they can be used in challenging locations. Selective arterial embolization is a complex procedure and often requires association with other treatments. Further studies are needed to confirm the effectiveness of denosumab and its side effects on skeletally immature patients. Curettage with adjuvants and autogenous bone grafting still shows promising results and can be used in larger, aggressive defects or superficial lesions. For simple bone cysts, the combination of curettage, bone graft, and ESIN showed the best results. Sclerotherapy for ABC also shows promising results.

Controversies in orthopaedic oncology.

Chondrosarcoma is the second most common surgically treated primary bone sarcoma. Despite a large number of scientific papers in the literature, there is still significant controversy about diagnostics, treatment of the primary tumour, subtypes, and complications. Therefore, consensus on its day-to-day treatment decisions is needed. In January 2024, the Birmingham Orthopaedic Oncology Meeting (BOOM) attempted to gain global consensus from 300 delegates from over 50 countries. The meeting focused on these critical areas and aimed to generate consensus statements based on evidence amalgamation and expert opinion from diverse geographical regions. In parallel, periprosthetic joint infection (PJI) in oncological reconstructions poses unique challenges due to factors such as adjuvant treatments, large exposures, and the complexity of surgery. The meeting debated two-stage revisions, antibiotic prophylaxis, managing acute PJI in patients undergoing chemotherapy, and defining the best strategies for wound management and allograft reconstruction. The objectives of the meeting extended beyond resolving immediate controversies. It sought to foster global collaboration among specialists attending the meeting, and to encourage future research projects to address unsolved dilemmas. By highlighting areas of disagreement and promoting collaborative research endeavours, this initiative aims to enhance treatment standards and potentially improve outcomes for patients globally. This paper sets out some of the controversies and questions that were debated in the meeting.

Electrochemotherapy in Spine Metastases: A Case Series Focused on Technical Aspects, Surgical Strategies and Results.

Metastases are complications of primary tumors due to prolonged cancer survival and have become an important issue for oncological patients and the most frequent cause of death and disability. Bone metastases occur at a later stage of cancer disease, and the spine is the most frequent site. To date, the aim of the treatment of metastases remains to be the control of disease and provide a satisfactory quality of life. The decision making of treatment is influenced by several factors such as the status of the primary disease, the number of metastases, site involvement, and the performance status of the patients. For this reason, the treatment of metastases is challenging and undergoes constant development. Therefore, alternative techniques with respect to surgery, which is the first option but not always practicable, and radiochemotherapy are attractive. Lately, electrochemotherapy has emerged as an innovative method for treating various primary and metastatic solid tumors, showing promising outcomes in terms of inducing tumor tissue necrosis and alleviating symptoms. This technique uses electric pulses to increase the uptake of chemotherapy by tumor cells. Despite the initial enthusiasm and good results in the treatment of bone tumors, relatively few papers have described its use in spine metastases. Therefore, we conducted a systemic review of this intriguing topic while also reporting our experience in the use of electrochemotherapy for the treatment of spine metastases.

Investigating and Practicing Orthopedics at the Intersection of Sex and Gender: Understanding the Physiological Basis, Pathology, and Treatment Response of Orthopedic Conditions by Adopting a Gender Lens: A Narrative Overview.

In the biomedical field, the differentiation between sex and gender is crucial for enhancing the understanding of human health and personalizing medical treatments, particularly within the domain of orthopedics. This distinction, often overlooked or misunderstood, is vital for dissecting and treating musculoskeletal conditions effectively. This review delves into the sex- and gender-specific physiology of bones, cartilage, ligaments, and tendons, highlighting how hormonal differences impact the musculoskeletal system's structure and function, and exploring the physiopathology of orthopedic conditions from an epidemiological, molecular, and clinical perspective, shedding light on the discrepancies in disease manifestation across sexes. Examples such as the higher rates of deformities (adolescent idiopathic and adult degenerative scoliosis and hallux valgus) in females and osteoporosis in postmenopausal women illustrate the critical role of sex and gender in orthopedic health. Additionally, the review addresses the morbidity-mortality paradox, where women, despite appearing less healthy on frailty indexes, show lower mortality rates, highlighting the complex interplay between biological and social determinants of health. Injuries and chronic orthopedic conditions such osteoarthritis exhibit gender- and sex-specific prevalence and progression patterns, necessitating a nuanced approach to treatment that considers these differences to optimize outcomes. Moreover, the review underscores the importance of recognizing the unique needs of sexual minority and gender-diverse individuals in orthopedic care, emphasizing the impact of gender-affirming hormone therapy on aspects like bone health and perioperative risks. To foster advancements in sex- and gender-specific orthopedics, we advocate for the strategic disaggregation of data by sex and gender and the inclusion of "Sexual Orientation and Gender Identity" (SOGI) data in research and clinical practice. Such measures can enrich clinical insights, ensure tailored patient care, and promote inclusivity within orthopedic treatments, ultimately enhancing the precision and effectiveness of care for diverse patient populations. Integrating sex and gender considerations into orthopedic research and practice is paramount for addressing the complex and varied needs of patients. By embracing this comprehensive approach, orthopedic medicine can move towards more personalized, effective, and inclusive treatment strategies, thereby improving patient outcomes and advancing the field.

The Evaluation and Management of Lung Metastases in Patients with Giant Cell Tumors of Bone in the Denosumab Era.

Giant cell tumor of bone (GCTB) is characterized by uncertain biological behavior due to its local aggressiveness and metastasizing potential. In this study, we conducted a meta-analysis of the contemporary literature to evaluate all management strategies for GCTB metastases. A combination of the terms "lung metastases", "giant cell tumor", "bone", "treatment", and "oncologic outcomes" returned 133 patients meeting our inclusion criteria: 64 males and 69 females, with a median age of 28 years (7-63), at the onset of primary GCTB. Lung metastases typically occur at a mean interval of 26 months (range: 0-143 months) after treatment of the primary site, commonly presenting as multiple and bilateral lesions. Various treatment approaches, including surgery, chemotherapy, radiotherapy, and drug administration, were employed, while 35 patients underwent routine monitoring only. Upon a mean follow-up of about 7 years (range: 1-32 years), 90% of patients were found to be alive, while 10% had died. Death occurred in 25% of patients who had chemotherapy, whereas 96% of those not treated or treated with Denosumab alone were alive at a mean follow-up of 6 years (range: 1-19 years). Given the typically favorable prognosis of lung metastases in patients with GCTB, additional interventions beyond a histological diagnosis confirmation may not be needed. Denosumab, by reducing the progression of the disease, can play a pivotal role in averting or delaying lung failure.

Ortho-oncoplastic surgery in foot and ankle: A narrative overview on reconstruction of soft-tissue defects after oncologic resections.

INTRODUCTION: Malignant tumors of the foot are rare, and treatment strategies are challenging considering the complex anatomy of this area. In recent years, dramatic advances in technology and collaborations between different specialties (such as orthopedic, oncology, radiology, plastic, and vascular surgery) significantly changed the approach to complex malignant tumors without resorting to limb removal. The combination of the strengths of both orthopedic surgery and plastic surgery constitutes the modern definition of "orthoplasty." The aim of this review article is to provide treatment strategies that are available for reconstruction of foot and ankle in limb-salvage surgery after tumor resection, with a specific focus on microsurgical techniques in plastic surgery. METHODS: We conducted a comprehensive search for relevant papers across PubMed, Scopus, Embase, and Web of Science. We included patient-based studies reporting on procedures for soft-tissue reconstruction with small and large soft tissue defects. Indications, pros and cons, and technique tips are discussed for each type of reconstructive technique. RESULTS: The search was done using literature of the past 30 years (from 1990 to date), resulting in about 725 articles describing over 2000 cases. Cutaneous flaps included lateral supramalleolar flap, medial plantar flap, reverse sural neurocutaneous island flap, medial leg flap, and lateral leg flap. Free flaps included anterolateral thigh flap, radial forearm flap, latissimus dorsi flap, gracilis muscle flap, lateral arm flap, and rectus abdominis flap. CONCLUSIONS: The orthoplastic approach in musculoskeletal oncology is a collaborative model of orthopedic and plastic surgeons working together, resulting in a higher rate of successful limb salvage in patients at risk for amputation. Protocols, biologic substitutes, and surgical techniques are largely improved in the last decades increasing the possibility of functional reconstruction. Microsurgical strategies represent the new frontiers in these demanding reconstructions.

When Is a Two-Stage Surgical Procedure Indicated in the Treatment of Pseudotumors of the Hip? A Retrospective Study of 21 Cases and a Review of the Literature.

(1) Background: A pseudotumor of the hip is a sterile, non-neoplastic soft tissue mass associated with total hip arthroplasties. Pseudotumors may mimic soft tissue tumors or infections, and thus a differential diagnosis is crucial, and biopsy is recommended. The purpose of this study was to compare the complications and functional results between one-stage and two-stage procedures. (2) Methods: We retrospectively analyzed 21 patients surgically treated at our institution with "pseudotumors" associated with hip prosthesis (8 male, 13 female with a mean age of 69 years). One-stage revision was performed in 10 cases and two-stage reversion in 10, with excision only in 1 case. Complications were classified as major and minor and functional results assessed using the Harris Hip Score (HHS). (3) Results: Five patients (24%) reported major complications. The survival rate for all complications was 75%. The overall survival rate was 95% at 5 years. The mean HHS ranged from 35 pre-op to 75 post-op, highlighting improved functional results in all cases. We recorded no differences in complications or functional outcomes between the one- and two-stage procedures. (4) Conclusions: In our experience, the two-stage surgical approach is preferable in cases with major bone defects and larger pseudotumor sizes. The use of custom-made 3D-printed prostheses is increasing and is a further reason to prefer two-stage revision.

Adaptive Shooting Disciplines: A Scoping Review of the Literature with Bibliometric Analysis.

Para-archery and para-shooting, two very popular adaptive shooting disciplines that have earned their place as major official events in the Paralympic Games, share some similarities, as well as distinctive features in terms of rules, physiological requirements, and equipment used. The International Paralympic Committee has a clear responsibility to ensure that all sports within its jurisdiction, including adaptive shooting, can achieve excellence in their respective fields. To achieve this, the conduct of well-designed studies and rigorous research is essential. Although some research has been conducted in this area, a comprehensive and systematic evaluation is still needed. Therefore, the present study aims to provide a thorough review and synthesis of existing research on adaptive shooting disciplines, identify strengths and gaps, and suggest future directions. Arksey and O'Malley's methodology is leveraged and enhanced with bibliometric and policy analyses to review literature on adaptive shooting. Databases like PubMed/MEDLINE, Scopus, Web of Science, OvidSP, and EMBASE were searched, focusing on studies in adaptive shooting disciplines and analysing these findings through a blend of thematic and statistical methods. Twenty-four studies totalling 483 para-athletes (299 para-shooters and 184 para-archers) are included in this scoping review, focusing on a range of aspects, including physiological responses (n = 9), research design and measurement methods for evidence-based classification (n = 6), biopsychosocial aspects (n = 3), development of new methods and technologies (n = 4), kinematic and biomechanical assessment (n = 1), and epidemiology of injuries (n = 1). Seven articles focused exclusively on para-archery, thirteen exclusively on para-shooting, and four on both para-archery and para-shooting. In conclusion, the available literature on adaptive shooting disciplines is still very limited, especially regarding para-archery compared to para-shooting. This highlights the need for further research in many key areas to ensure a better understanding of the different disciplines and to provide appropriate support for para-athletes. Future research in para-archery and para-shooting should focus on technological innovations, biomechanical studies, and psychological support to enhance athlete performance and accessibility. Addressing the imbalance between the two disciplines, along with injury prevention and global participation, can drive the sports towards greater inclusivity and equity for para-athletes worldwide.

Are IDH1 R132 Mutations Associated With Poor Prognosis in Patients With Chondrosarcoma of the Bone?

BACKGROUND: Because chondrosarcomas vary widely in their behavior, and because anticipating their behavior based on histology alone can be challenging, genetic markers represent an appealing area of inquiry that may help us refine our prognostic approaches. Isocitrate dehydrogenase (IDH) mutations are involved in the pathogenesis of a variety of neoplasms, and recently, IDH1/2 mutations have been found in the tissue of benign cartilage tumors as well as in conventional chondrosarcomas and highly aggressive dedifferentiated chondrosarcomas. However, their association with patient survival is still controversial. QUESTIONS/PURPOSES: (1) What proportion of patients with chondrosarcomas carry IDH mutations, and which IDH mutations can be found? (2) Are any specific IDH mutations associated with poorer overall survival, metastasis-free survival, or local recurrence-free survival? METHODS: Between April 2017 and December 2022, we treated 74 patients for atypical cartilaginous tumors or chondrosarcomas in a musculoskeletal tumor referral center. Patients were considered potentially eligible for the present study if the histologic diagnosis was confirmed by two expert soft tissue and bone pathologists following the current WHO classification, complete preoperative imaging and follow-up data were available, surgical excision was performed by sarcoma orthopaedic surgeons directed by a team leader, and the minimum follow-up was 2 years after surgical treatment unless the patient died. Data including sex, age, diagnosis, grade, type of operation, local recurrence, metastasis, and oncologic follow-up were recorded. Forty-one patients (55%) were eligible for the study. For each patient, DNA was extracted and quantified from paraffin-embedded sections of tumor tissue, and the mutational status of IDH1 (codons 105 and 132) and IDH2 (codons 140 and 172) genes was assessed. Of those, 56% (23 of 41) of patients had adequate DNA for analysis of IDH mutations: 10 male and 13 female patients, with a median age of 59 years (range 15 to 98 years). There were 22 conventional chondrosarcomas (8 atypical cartilaginous tumors, 11 Grade 2, and 3 Grade 3) and 1 dedifferentiated chondrosarcoma. Stage was IA in 3 patients, IB in 5, IIA in 1, IIB in 13, and III in 1, according to the Musculoskeletal Tumor Society classification. At a median follow-up of 3.5 years (range 4 months to 5.6 years), 14 patients were disease-free, 2 were alive with disease, and 7 died (3 within 2 years from surgery). Eight patients had metastases, and 7 developed local recurrence. We determined the proportion of patients who carried IDH mutations, and compared patients with and without those mutations in terms of overall survival, metastasis-free survival, and local recurrence-free survival using Kaplan-Meier curves. RESULTS: Six patients showed wild-type IDH genes, and 17 had IDH mutations (12 had IDH1 R132, 3 had IDH1 G105, and 2 had IDH2 R172). Overall survival at 2 years using the Kaplan-Meier estimator was lower in patients with an IDH mutation than in those with the wild-type gene (75% [95% confidence interval 50% to 99%] versus 100% [95% CI 100% to 100%]; p = 0.002). Two-year metastasis-free survival was also lower in patients with an IDH mutation than in those with the wild-type gene (33% [95% CI 7% to 60%] versus 100% [95% CI 100% to 100%]; p = 0.001), as was 2-year local recurrence-free survival (70% [95% CI 42% to 98%] versus 100% [95% CI 100% to 100%]; p = 0.02). CONCLUSION: We found that IDH1 R132 mutations were negatively associated with the prognosis of patients with bone chondrosarcomas. Nevertheless, more extensive studies (such as multicenter international studies) are needed and advisable to confirm our observations in this preliminary small series. Moreover, evaluating mutational status in fresh samples instead of in paraffin-embedded sections could help to increase the number of patients with adequate DNA for analysis. If our findings will be confirmed, the evaluation of IDH mutational status in biopsy samples or resection specimens could be considered when stratifying patients, highlighting those who may benefit from more aggressive treatment (such as adjuvant chemotherapy) or closer follow-up. LEVEL OF EVIDENCE: Level III, prognostic study.

Primary vascular tumors of bone: A comprehensive literature review on classification, diagnosis and treatment.

Primary vascular tumors of bone are a heterogeneous group of neoplasms, ranging from benign hemangiomas to frankly malignant epithelioid hemangioendotheliomas and angiosarcomas. Over the years, their classification has been a matter of discussion, due to morphologic similarities and uncertainty regarding biologic behavior. Over the past decade, with the development of next-generation sequencing, there has been a significant improvement in the molecular characterization of these lesions. The integration of their morphologic, immunohistochemical and molecular features has led to a better stratification, with important prognostic and therapeutic implications. Nevertheless, primary vascular bone tumors still represent a challenge for medical oncologists. Given their rarity and heterogeneity, in the last few years, there has been no significant progress in medical treatment options, so further research is needed. Here we present a review of the current knowledge regarding primary vascular tumors of the bone, correlating clinicopathologic features with tumor behavior and therapeutic approaches.

Desmoid Tumors in the Active Surveillance Era: Evaluation of Treatment Options and Pain Relief in a Single-Center Retrospective Analysis.

In patients with desmoid tumors (DTs), active surveillance has been increasingly preferred over surgery, while treatment (including pharmacological therapy, radiotherapy, and/or surgery) is performed in cases with confirmed disease progression. This study aimed to evaluate event-free survival and pain management according to different treatment strategies. We evaluated event-free survival, including recurrence after initial surgical treatment or changes in the therapeutic management after initial non-surgical treatment and pain management according to different treatment strategies. All patients referred for DT in 2001-2021 at our institutions were stratified into four groups: those treated surgically prior to 2012 (SGPre12) or after 2012 (SGPost12), those treated pharmacologically (MG), and those under active surveillance (ASG). An event was defined as recurrence after initial surgical treatment or a change in therapeutic management. Overall, 123 patients were included in the study: 28 in SGPre12, 41 in SGPost12, 38 in MG, and 16 in ASG. Pharmacological treatment resolved painful symptoms in 16/27 (60%) patients (p = 0.0001). The median follow-up duration was 40 months (IQR 23-74). Event-free survival at 1, 3, and 5 years was: 85%, 70%, and 62% in SGPre12; 76%, 58%, and 49% in SGPost12; 49%, 31%, and 31% in MG; and 45%, 45%, and 45% in ASG. Our findings support the role of active surveillance as initial management, as demonstrated by the fact that about half the patients did not experience any progression, while surgery can be reserved as a first-line approach for selected patients. In terms of pain relief, medical therapy led to symptom resolution in more than half the cases.

Analysis of Kinematic and Muscular Fatigue in Long-Distance Swimmers.

Muscle fatigue is a complex phenomenon that is influenced by the type of activity performed and often manifests as a decline in motor performance (mechanical failure). The purpose of our study was to investigate the compensatory strategies used to mitigate mechanical failure. A cohort of 21 swimmers underwent a front-crawl swimming task, which required the consistent maintenance of a constant speed for the maximum duration. The evaluation included three phases: non-fatigue, pre-mechanical failure, and mechanical failure. We quantified key kinematic metrics, including velocity, distance travelled, stroke frequency, stroke length, and stroke index. In addition, electromyographic (EMG) metrics, including the Root-Mean-Square amplitude and Mean Frequency of the EMG power spectrum, were obtained for 12 muscles to examine the electrical manifestations of muscle fatigue. Between the first and second phases, the athletes covered a distance of 919.38 ± 147.29 m at an average speed of 1.57 ± 0.08 m/s with an average muscle fatigue level of 12%. Almost all evaluated muscles showed a significant increase (p < 0.001) in their EMG activity, except for the latissimus dorsi, which showed a 17% reduction (ES 0.906, p < 0.001) during the push phase of the stroke cycle. Kinematic parameters showed a 6% decrease in stroke length (ES 0.948, p < 0.001), which was counteracted by a 7% increase in stroke frequency (ES -0.931, p < 0.001). Notably, the stroke index also decreased by 6% (ES 0.965, p < 0.001). In the third phase, characterised by the loss of the ability to maintain the predetermined rhythm, both EMG and kinematic parameters showed reductions compared to the previous two phases. Swimmers employed common compensatory strategies for coping with fatigue; however, the ability to maintain a predetermined motor output proved to be limited at certain levels of fatigue and loss of swimming efficiency (Protocol ID: NCT06069440).

Management of metastatic bone disease of the pelvis: current concepts.

PURPOSE: Metastatic disease of the pelvis is frequently associated with severe pain and impaired ambulatory function. Depending on the patient's characteristics, primary tumor, and metastatic pelvic disease, the treatment choice may be varied. This study aims to report on the current management options of metastatic pelvic disease. METHODS: We comprehensively researched multiple databases and evaluated essential studies about current concepts of managing a metastatic bone disease of the pelvis, focusing on specific indications as well as on the result of treatment. RESULTS: Pelvic metastases not in the periacetabular region can be managed with modification of weight-bearing, analgesics, bisphosphonates, chemotherapy and/or radiotherapy. Minimally invasive approaches include radiofrequency ablation, cryoablation, embolization, percutaneous osteoplasty, and percutaneous screw placement. Pathological or impending periacetabular fracture, excessive periacetabular bone defect, radioresistant tumor, and persistent debilitating pain despite non-surgical treatment and/or minimally invasive procedures can be managed with different surgical techniques. Overall, treatment can be divided into nonoperative, minimally invasive, and operative based on specific indications, the expectations of the patient and the lesion. CONCLUSION: Different treatment modalities exist to manage metastatic pelvic bone disease. Decision-making for the most appropriate treatment should be made with a multidisciplinary approach based on a case-by-case basis.

A New Player in the Mechanobiology of Deep Fascia: Yes-Associated Protein (YAP).

Recent studies have demonstrated that fascial fibroblasts are susceptible to mechanical stimuli, leading to the remodeling of the extracellular matrix (ECM). Moreover, the extensive literature on Yes-associated protein (YAP) has shown its role in cell mechanics, linking cell properties, such as shape, adhesion, and size, to the expression of specific genes. The aim of this study was to investigate the presence of YAP in deep fascia and its activation after a mechanical stimulus was induced via a focal extracorporeal shockwave (fESW) treatment. Thoracolumbar fascia (TLF) samples were collected from eight patients (age: 30-70 years; four males and four females) who had undergone spine elective surgical procedures at the Orthopedic Clinic of University of Padova. YAP was measured in both tissue and TLF-derived fibroblasts through immunoblotting. COL1A1 and HABP2 gene expression were also evaluated in fibroblasts 2, 24, and 48 h after the fESW treatment. YAP was expressed in all the examined tissues. The ratio between the active/inactive forms (YAP/p-YAP) of the protein significantly increased in fascial fibroblasts after mechanical stimulation compared to untreated cells (p = 0.0022). Furthermore, COL1A1 and HABP2 gene expression levels were increased upon treatment. These findings demonstrate that YAP is expressed in the deep fascia of the thoracolumbar region, suggesting its involvement in fascial mechanotransduction processes, remodeling, regeneration, and fibrogenesis. This study indicates, for the first time, that YAP is a "new player" in the mechanobiology of deep fascia.

Biomechanics of Chondrocytes and Chondrons in Healthy Conditions and Osteoarthritis: A Review of the Mechanical Characterisations at the Microscale.

Biomechanical studies are expanding across a variety of fields, from biomedicine to biomedical engineering. From the molecular to the system level, mechanical stimuli are crucial regulators of the development of organs and tissues, their growth and related processes such as remodelling, regeneration or disease. When dealing with cell mechanics, various experimental techniques have been developed to analyse the passive response of cells; however, cell variability and the extraction process, complex experimental procedures and different models and assumptions may affect the resulting mechanical properties. For these purposes, this review was aimed at collecting the available literature focused on experimental chondrocyte and chondron biomechanics with direct connection to their biochemical functions and activities, in order to point out important information regarding the planning of an experimental test or a comparison with the available results. In particular, this review highlighted (i) the most common experimental techniques used, (ii) the results and models adopted by different authors, (iii) a critical perspective on features that could affect the results and finally (iv) the quantification of structural and mechanical changes due to a degenerative pathology such as osteoarthritis.