The role of macrophage polarization in tendon healing and therapeutic strategies: Insights from animal models.

Tendon injuries, a common musculoskeletal issue, usually result in adhesions to the surrounding tissue, that will impact functional recovery. Macrophages, particularly through their M1 and M2 polarizations, play a pivotal role in the inflammatory and healing phases of tendon repair. In this review, we explore the role of macrophage polarization in tendon healing, focusing on insights from animal models. The review delves into the complex interplay of macrophages in tendon pathology, detailing how various macrophage phenotypes contribute to both healing and adhesion formation. It also explores the potential of modulating macrophage activity to enhance tendon repair and minimize adhesions. With advancements in understanding macrophage behavior and the development of innovative biomaterials, this review highlights promising therapeutic strategies for tendon injuries.

Evolution of orthopaedic diseases through four thousand three hundred years: from ancient Egypt with virtual examinations of mummies to the twenty-first century.

PURPOSE: This study conducts a comprehensive comparative analysis of bone pathologies between ancient Egypt and today. We aim to elucidate the prevalence, types, and potential aetiological factors influencing skeletal disorders in these two distinct temporal and cultural contexts. METHODS: The research employs a multidisciplinary approach, integrating osteological, paleopathological, and historical data to understand bone pathologies in mummies and the actual world. Applying radiographs and CT scans as noninvasive techniques has shed new light on past diseases such as fractures, dysplasia, osteoarthritis, surgery, and tuberculosis. Virtual inspection has almost replaced classical autopsy and is essential, especially when dealing with museum specimens. RESULTS: Findings indicate no significant disparities in the prevalence and types of bone pathologies through 4300 years of evolution. Moreover, this study sheds light on the impact of sociocultural factors on bone health. Examination of ancient Egypt's burial practices and associated cultural beliefs provides insights into potential behavioral and ritualistic influences on bone pathologies and the prevalence of specific pathologies in the past and present. CONCLUSION: This comparative analysis illuminates the dynamic of bone pathologies, highlighting the interplay of biological, cultural, and environmental factors. By synthesizing archeological and clinical data, this research contributes to a more nuanced understanding of skeletal health's complexities in ancient and modern societies, offering valuable insights for anthropological and clinical disciplines.

Scoping out the past: meniscus examination with arthroscopy; the light arrived in the knee before the end of World War I with the cystoscope, Fresnel's lens, and Edison's lamp.

PURPOSE: Before radiology and arthroscopy, an arthrotomy had to be made for a definitive diagnosis and treat intraarticular pathology. Before arthroscopy, endoscopy was performed on other organs, and particularly the bladder. This paper aimed to investigate the transition of the cystoscope to the arthroscope, and all the bright innovations about light and optics that finally allow arthroscopy. METHODS: Physicians have always wanted to examine their patients' body cavities. Some cavities are quite accessible for diagnostic purposes, using specula and light, while others are difficult to inspect. The female bladder was the first organ to be examined using an endoscope with some light by Philipp Bozzini in 1806. We report the important innovations and inventions done by surgeons but also by scientists in optic and electricity during two centuries before arriving to arthroscopy. RESULTS: Whereas the urologists immediately embraced the idea of endoscopy, and adapted the rules of optic and the progress in electricity to allow bladder illumination and examination with cystoscopes, the orthopedic surgeons were reluctant. We focus on the early history of endoscopy and arthroscopy specifically. Our story ends in 1918 with Dr. Severin Nordentoft in Germany and Professor Kenji Takagi in Japan began with cystoscopes before designing the first arthroscopes for performing the first knee arthroscopies. CONCLUSION: We document some crucial figures on the thorny path, from cystoscopy to adopting the arthroscope as a useful orthopaedic tool.

Minimally invasive small incision surgical technique for unicompartmental knee arthroplasty.

PURPOSE: It is always a challenge for orthopaedic surgeons to minimise surgical incisions while ensuring excellent surgical results. We propose the minimally invasive small incision (MISI) technique and an extramedullary positioning technique in the unicompartmental knee arthroplasty (UKA) surgery. This study aimed to clarify the early postoperative clinical outcomes and component alignment between MISI and conventional minimally invasive surgical (MIS) techniques. METHODS: We prospectively enrolled 60 patients who underwent MISI-UKA and 60 patients who underwent MIS-UKA as controls. Clinical parameters include the time of straight leg raising, postoperative walking time with walker assistance, hospital stay, Numerical Rating Scale (NRS) pain score and Knee Society Score (KSS). The postoperative components and lower extremity alignment were compared between the two groups with radiographic image measurement. RESULTS: The MISI group obtained a smaller incision during knee extension (P < 0.001) but a longer tourniquet usage time than the MIS group. The MISI group lost less blood (P < 0.001). The MISI group achieved straight leg raising and walking with aid earlier after surgery, with a shorter hospital stay than the MIS group (P < 0.001). Range of motion (ROM), NRS and KSS scores revealed no significant difference between the two groups in six months postoperative follow-up (P > 0.05). Radiographic measurement results between the two groups revealed no statistical difference (P > 0.05) CONCLUSION: The MISI-UKA could achieve faster earlier recovery after surgery and shorter hospital stays without compromising the principles of proper prosthesis position and limb alignment compared with the conventional MIS-UKA.

Lateral meniscus with tears or with histologic calcification does not increase the risk of lateral osteoarthritis after medial unicompartmental arthroplasty.

PURPOSE: Meniscal tears or histological meniscal calcifications (in the absence of radiological chondrocalcinosis) are frequent in osteoarthritis. Whether lateral meniscal lesions influence clinical outcomes after medial unicompartmental knee arthroplasty (UKA) is unknown. METHODS: We analyzed 130 patients (130 knees) with medial unicompartmental knee arthroplasties between 2005 and 2015. These 130 knees had full articular cartilage thickness in the lateral compartment and no radiological chondrocalcinosis on preoperative radiographs. The lateral meniscus was analyzed with preoperative MRI and a biopsy of the anterior horn at the time of surgery. Synovial fluid was collected and analyzed for calcium pyrophosphate dihydrate crystal deposition (CPPD crystals). Lateral meniscal tears were untreated when detected on MRI or during surgery, with the hypothesis that these tears on the opposite compartment would remain asymptomatic in medial UKA. At average 10-year follow-up, patients were evaluated with clinical and radiographic outcome, with a focus on the risk of joint space narrowing of the lateral femorotibial compartment. RESULTS: CPPD crystals were present in the synovial fluid of 70 knees. Lateral meniscal tears were seen on MRI in 34 (49%) normal meniscuses of the 60 knees without CPPD crystals and in six other knees without histological meniscal calcification despite CPPD crystals. Histological calcification was present on 61 lateral meniscuses with 53 meniscal tears. The results showed no significant differences in the clinical outcomes between knees with lateral meniscal tears or lateral meniscal histological chondrocalcinosis or both lesions and those without these conditions. Additionally, radiographic progression of osteoarthritis in the opposite femorotibial compartment of the knee was not more frequent in patients with these meniscal issues. The ten year cumulative survival rates, measured by the need for total knee arthroplasty, were 91% for knees without meniscal lesions and 92% for knees with these lesions. CONCLUSION: On this basis, treatment of meniscal tears of the lateral compartment and routine aspiration of the knee to assess for birefringent crystals in the planning of medial UKA do not appear necessary.

Revision hip arthroplasty dislocation risk calculator: when to select dual mobility, large heads, constrained liners, or a standard head size? Testing one hundred thousand hip revisions with artificial intelligence.

PURPOSE: Preventing dislocation with large head (≥ 36 mm), dual mobility, or constrained acetabular liner is another option than a standard (≤ 32 mm). Many other dislocations risk factors than size of the femoral head exist after hip arthroplasty revision. Predicting dislocation with a calculator according to the implant, to the indication of revision, and to patient's risks could allow a better surgery decision. METHODS: Our search method covers the period from 2000 to 2022. A total of 470 relevant citations on hip major revision (cup or stem or both revisions) were identified with artificial intelligence comprising 235 publications of 54,742 standard heads comprising 142 publications of 35,270 large heads, comprising 41 publications of 3945 constrained acetabular components, and 52 publications of 10,424 dual mobility implants. We considered four implant types (standard, large head, dual mobility, or constrained acetabular liner) as the entry layer of the artificial neural network (ANN). Indication for revision THA was the second hidden layer. Demographics, spine surgery, and neurologic disease were the third layer. Implant revision, reconstruction process as next input (hidden layer). Surgery-related factors, and so on. The output was a postoperative dislocation or not. RESULTS: Of the 104,381 hips that underwent a major revision, a second revision for dislocation was performed for 9234 hips. In each implant group, dislocation remained the first cause of revision. The rate of second revision for dislocation as a percentage of first revision procedures was significantly higher in the standard head group (11.8%) than in the constrained acetabular liner group (4.5%), the dual mobility group (4.1%), and the large head group (6.1%). Instability of a previous THA, infection, or periprosthetic fracture as the indication for revision was increased risk factors as compared with aseptic loosening. One hundred variables were used to create the calculator with the best parameter combination of data and ranking the different factors, according to the four implant types (standard, large head, dual mobility, or constrained acetabular liner). CONCLUSION: The calculator can be used as a tool to identify patients at risk for dislocation after hip arthroplasty revision and individualize recommendations to select another option than a standard head size.

Orthobiologics: a review.

PURPOSE: The use of biologic materials in orthopaedics (orthobiologics) has gained significant attention over the past years. To enhance the body of the related literature, this review article is aimed at summarizing these novel biologic therapies in orthopaedics and at discussing their multiple clinical implementations and outcomes. METHODS: This review of the literature presents the methods, clinical applications, impact, cost-effectiveness, and outcomes, as well as the current indications and future perspectives of orthobiologics, namely, platelet-rich plasma, mesenchymal stem cells, bone marrow aspirate concentrate, growth factors, and tissue engineering. RESULTS: Currently available studies have used variable methods of research including biologic materials as well as patient populations and outcome measurements, therefore making comparison of studies difficult. Key features for the study and use of orthobiologics include minimal invasiveness, great healing potential, and reasonable cost as a nonoperative treatment option. Their clinical applications have been described for common orthopaedic pathologies such as osteoarthritis, articular cartilage defects, bone defects and fracture nonunions, ligament injuries, and tendinopathies. CONCLUSIONS: Orthobiologics-based therapies have shown noticeable clinical results at the short- and mid-term. It is crucial that these therapies remain effective and stable in the long term. The optimal design for a successful scaffold remains to be further determined.

Prognosis of hip osteonecrosis after cell therapy with a calculator and artificial intelligence: ten year collapse-free survival prediction on three thousand and twenty one hips.

PURPOSE: Several reports have identified prognostic factors for hip osteonecrosis treated with cell therapy, but no study investigated the accuracy of artificial intelligence method such as machine learning and artificial neural network (ANN) to predict the efficiency of the treatment. We determined the benefit of cell therapy compared with core decompression or natural evolution, and developed machine-learning algorithms for predicting ten year collapse-free survival in hip osteonecrosis treated with cell therapy. Using the best algorithm, we propose a calculator for "prognosis hip osteonecrosis cell therapy (PHOCT)" accessible for clinical use. METHODS: A total of 3145 patients with 5261 osteonecroses without collapses were included in this study, comprising 1321 (42%) men and 1824 (58%) women, with a median age of 34 (12-62) years. Cell therapy was the treatment for 3021 hips, core decompression alone for 1374 hips, while absence of treatment was the control group of 764 hips. First, logistic regression and binary logistic regression analysis were performed to compare results of the three groups at ten years. Then an artificial neural network model was developed for ten year collapse-free survival after cell therapy. The models' performances were compared. The algorithms were assessed by calibration, and performance, and with c-statistic as measure of discrimination. It ranges from 0.5 to 1.0, with 1.0 being perfect discrimination and 0.5 poor (no better than chance at making a prediction). RESULTS: Among the 3021 hips with cell therapy, 1964 hips (65%) were collapse-free survival at ten years, versus 453 (33%) among those 1374 treated with core decompression alone, and versus 115 (15%) among 764 hips with natural evolution. We analyzed factors influencing the prediction of collapse-free period with classical statistics and artificial intelligence among hips with cell therapy. After selecting variables, a machine learning algorithm created a prognosis osteonecrosis cell therapy calculator (POCT). This calculator proved to have good accuracy on validation in these series of 3021 hip osteonecroses treated with cell therapy. The algorithm had a c-statistic of 0.871 suggesting good-to-excellent discrimination when all the osteonecroses were mixed. The c-statistics were calculated separately for subpopulations of categorical osteonecroses. It retained good accuracy, but underestimated ten year survival in some subgroups, suggesting that specific calculators could be useful for some subgroups. This study highlights the importance of multimodal evaluation of patient parameters and shows the degree to which the outcome is modified by some decisions that are within a surgeon's control, as the number of cells to aspirate, the choice of injecting in both the osteonecrosis and the healthy bone, the choice between unilateral or bilateral injection, and the possibility to do a repeat injection. CONCLUSION: Many disease conditions and the heterogeneities of patients are causes of variation of outcome after cell therapy for osteonecrosis. Predicting therapeutic effectiveness with a calculator allows a good discrimination to target patients who are most likely to benefit from this intervention.

Orthopaedic surgery as seen by artists and by surgeons: science or art?

PURPOSE: Artists, including painters, are interested in capturing the essence of the world around them, including surgery. Therefore, we explored the world of orthopaedic surgery through the eyes of artists. We asked how artists and painters have captured the artistic vision of orthopaedic surgery by describing the operation, tools and techniques used, and the patients and surgeons involved. METHODS: The evolution of medical science and the importance of an orthopaedic surgeon art in society during different centuries were evaluated from ancient civilizations to the modern world. The symbolic representation of orthopaedic surgery and orthopaedic surgeons was analyzed over time, to reflect changes in medical practice and societal attitudes towards orthopaedic surgery. RESULTS: Ancient Egypt is where the first instances of painting a shoulder dislocation reduction were discovered. The first report of organized surgical care is found in Homer's epic poem "Iliad," even if executing surgical operations and artistic representation was undoubtedly done in many ancient civilizations. Orthopaedic surgeons according to the period were represented as gods, saints, monks, heroic figures, military surgeons, and sometimes politics. However, the orthopaedic surgeon was rarely considered an artist by those who are real artists. Paintings often showed orthopedists in action, with blood and tools, emphasizing the gritty reality of the surgical profession, sometimes with some stereotypes (gargantuan figure, gorilla). However, the common thread is the recognition of the skill, knowledge, and dedication required to be a surgeon and the importance of their work in helping people live healthier and more active lives. CONCLUSION: Overall, painters have depicted orthopedic surgeons as skilled professionals who are dedicated to helping their patients achieve better health and mobility. Their depictions have evolved over time, reflecting changes in medical practice and the wider culture. However, the essential message remains the same: orthopaedic surgeons play a vital role in helping people live healthier, more active lives.

Rubber gloves in orthopaedic surgery (part II): Cooke and Goodyear; Halsted and Caroline's gloves of love; from cotton to rubber after Perthes' experiments; double glove technique with Urist.

PURPOSE: This study determines the timeline for surgeons adopting rubber gloves and the double glove technique in the operating room for orthopaedic surgery. MATERIAL AND METHODS: Using the vague historical terms of discovery, acceptance, commonplace, and consistency, we analyzed the influence of the different actors in each period. RESULTS: Cotton or silk was used for early gloves; they were permeable, sometimes coated with paraffin. Uses of rubber date to the 1600 s when the Mesoamericans used rubber to make shoes. After the discovery of rubber in 1735 by the French scientist Charles de la Condamine in Peru, the rubber glove was imagined in 1834 and done for the first time by R. F. Cooke. The acceptance of rubber gloves arrived when the Goodyear-Rubber Society began to manufacture rubber gloves. Halsted, at Johns Hopkins Hospital, negotiated in 1889 with the Goodyear Rubber Company to produce thin rubber gloves to protect his nurse's hands from the dermatologic effects of the carbolic acid used to sterilize instruments. Commonplace to protect patients from bacteria of hand surgeons necessitated several decades. Dr. Joseph Bloodgood (Halsted's senior resident) remarked that gloving the surgeon with rubber gloves reduced the infection rate. Still, surgeons were reluctant to wear gloves that impaired the sense of touch. Laboratory experiments performed by G. Perthes on cotton and rubber gloves were necessary to generalize rubber gloves for practice in orthopaedic surgery. Consistency of the double-glove technique arrived during World War II when M. Urist proposed the double protection against bites from bone or bullet fragments while exploring war wounds. Only in 1965, when The Ansell Rubber Company utilized gamma irradiation as a low-cost method of sterilizing the gloves they produced, did disposable gloves become sterile. CONCLUSION: This article helps to understand the detailed discussions before surgical gloves' modern operating equipment.