Introduction

Degenerative meniscal tears are the most common meniscal lesions, representing huge clinical and socio-economic burdens. Their role in knee osteoarthritis (OA) onset and progression is well established and demonstrated by several retrospective studies. Effective preventive measures and non-surgical treatments for degenerative meniscal lesions are still lacking, also because of the lack of specific and accurate animal models in which test them. Thus, we aim to develop and validate an accurate animal model of meniscus degeneration.

Introduction and Objective

Over the past few years, a reorganization of the educational pathways has been promoted with the purpose of optimizing the acquisition of competences and their assessment, so as to reduce the risks to both health care professionals and end users. Virtual reality (VR) has been repeatedly tested, initially as a positive reinforcement for more traditional educational pathways and, more recently, as their potential substitute. The aim of this study was to demonstrate the potentiality of VR simulation training in spine surgery.

Introduction and Objective

Kinematic Alignment (KA) is a surgical technique that restores the native knee alignment following Total Knee Arthroplasty (TKA). The association of this technique with a medial pivot implant design (MP) attempts to reestablish the physiological kinematics of the knee. Aim of this study is to analyze the clinical and radiological outcomes of patients undergoing MP-TKA with kinematic alignment, and to assess the effect of the limb alignment and the orientation of the tibial component on the clinical outcomes.

The COVID-19 virus is a tremendous burden for the Italian health system. The regionally-based Italian National Health System has been reorganized. Hospitals' biggest challenge was to create new intensive care unit (ICU) beds, as the existing system was insufficient to meet new demand, especially in the most affected areas. Our institution in the Milan metropolitan area of Lombardy, the epicentre of the infection, was selected as one of the three regional hub for major trauma, serving a population of more than three million people. The aims were the increase the ICU beds and the rationalization of human and structural resources available for treating COVID-19 patients. In our hub hospital, the reorganization aimed to reduce the risk of infection and to obtained resources, in terms of beds and healthcare personnel to be use in the COVID-19 emergency. Non-urgent outpatient orthopaedic activity and elective surgery was also suspended. A training programme for healthcare personnel started immediately. Orthopaedic and radiological pathways dedicated to COVID-19 patients, or with possible infection, have been established. In our orthopaedic department, we passed from 70 to 26 beds. Our goal is to treat trauma surgery's patient in the “golden 72 hours” in order to reduce the overall hospital length of stay. We applied an objective priority system to manage the flow of surgical procedures in the emergency room based on clinical outcomes and guidelines. Organizing the present to face the emergency is a challenge, but in the global plan of changes in hospital management one must also think about the near future. We reported the Milan metropolitan area orthopaedic surgery management during the COVID-19 pandemic. Our decisions are not based on scientific evidence; therefore, the decision on how reorganize hospitals will likely remain in the hands of individual countries.

Summary Statement

Mesenchymal stem cells from minced umbilical cord fragments may represent a valuable cell population for cartilage and bone tissue engineering

Summary Statement

In this study, massive rotator cuff tears were treated using an absorbable collagen-based patch or a non-absorbable synthetic patch. Results demonstrated the efficacy of the use of the synthetic prolene patch especially for elderly patients

PURPOSE OF THE STUDY: We reported of eleven cases of early spontaneous osteonecrosis (SO) of the knee successfully treated with an extracorporeal shock-wave treatment (ESWT).

Traumatic and vascular theories have been proposed as the cause of the SO, lack of blood in some critical areas, such as subchondral bone of femoral condyles or tibial plateaus, has been considered the underlying condition of this pathology.

ESWT can be suggested as an effective conservative treatment for SO of the knee.

MATERIALS AND METHODS: Ten patients with medial femoral condyle osteonecrosis of the knee (one bilateral) were evaluated. Exclusion criteria was evidence of a structural collapse of subchondral bone. Two patients had received a femoro-popliteal by-pass within the last year, while others five presented a deficit of the vascular axis of the homolateral lower limb documented by an eco-colordoppler. A clinical evaluation was taken at the diagnosis using KSS, PPI, NRS and VAS. Plain radiographs and MRI confirmed the diagnosis of osteonecrosis.

Patients were treated with a cycle of three ESWT performed with 2000 pulses of 0,28 mJ/mm2 with Wolf Piezoson 300 with 6,5 MHz ultrasounds for three times in a month.

Clinical evaluation was performed at first and at third month after treatment and a MRI evaluation was performed at fourth month after treatment.

RESULTS: Clinical evaluation showed a significant improvement of symptoms and articular functionality. MRI of all cases revealed the continuity of the cartilage with a reduction in bone marrow edema and no collapse of lesion.

DISCUSSION: In our study, a single cycle of ESWT produced an improvement of the clinical and MRI aspects in eleven cases of SO of the knee. The neo-angiogenetic effect of the ESWT appears to accelerate the time for the symptom remission.

ESWT might have the potential to avoid the need for surgical treatment.

The shoulder girdle is an extremely mobile joint. Rotator cuff tears alter the existing equilibrium between bony structures and muscles. The “subacromial impingement syndrome” resulting from this unbalance leads to an extension of the rotator cuff lesion.

Many authors have postulated a “mechanism of compensation”, but its existence still requires evidence. According to this model, the longitudinal muscles of the shoulder and the undamaged muscles of the rotator cuff would be able to functionally compensate, supersede the function of rotator cuff, and reduce symptoms.

The aim of this study was to evaluate muscular activation of the medium fibers of deltoid, the superior fibers of pectoralis major, the latissimus dorsi and the infraspinatus by a superficial electromyographic study (EMG) and the analysis of kinematics in patients with a massive rotator cuff tear.

We evaluated 30 subjects: 15 had pauci-symptomatic massive rotator cuff tear (modest pain and preserved movement), and 15 were healthy controls.

Paired t-test showed significant different activations (p< 0.05) of these 4 muscles between the pathological joint and the healthy one in the same patient.

The unpaired t-test, after comparing the mean EMG values of the 4 muscles, produced a significant difference (p< 0.05) between the experimental group and control group.

This study showed that a mechanism of muscular compensation is activated in patients suffering from rotator cuff tear, involving the deltoid and the infra-spinatus muscle, as already presented in literature, but also demonstrated the activation of 2 other muscles: the latissimus dorsi and the pectoralis major. It is, therefore, probable that, in these patients, these muscles, which would not normally pull the head of the humerus downwards, adapt in order to compensate for the pathological situation. We believe that these data are valuable in the surgical and rehabilitation planning in patients with a massive rotator cuff tear.

Aims: The treatment of long bone non-union now days finds its gold standard in autologous bone grafting. Since this technique is affected by a high morbidity rate of the donor site, many studies tried to find valid alternatives to this procedure, but during the last few years the advances made in tissue engineering techniques opened new frontiers.

In this study BMPs/AGFs were used in posttraumatic long bone non-union and osseous defects to test their clinical and radiological effectiveness in order to find a valid alternative to autologous bone grafting.

Methods: The cases selected can be divided in two groups. Group A: Patients affected by long bones Non Union, 9 months minimum duration, who are judged not to heal by simply changing the osteosynthesis device. Group B: Patients with non neoplastic, posttrauma or post-resection osseous defects of a critical size that will probably not heal using traditional surgical techniques or for which such techniques are considered to be unsuitable.

Moreover, the overall recruitment period is 3 years during which 40 patients/year will be enrolled up to a total of 120 cases; half of these will be treated with rhBMP-7 and the other half with PRP.

Results: Only 66 patients can be evaluated as they have completed the minimum follow-up period of 9 months, 35 of whom have been treated with rhBMP-7 and 31 treated with PRP. Advanced results indicate the RX Healing rate was 85% for BMP-7 and 68% for PRP with a Clinical Healing rate of 88.5% and 68%; therefore a higher efficiency of BMP-7 over PRP was found, confirmed by a significant failure rate of 15% versus 32,3% between BMP-7 and PRP, respectively.

Conclusions: According to our results, the use of growth factors showed a similar effectiveness to autologous bone grafting with better tolerability, moreover, a relevant difference in healing/failure rate between rhBMP-7 and PRP is observed.

Introduction: The purpose of this work is to create an in vitro model of engineered osteochondral composite by combining a cylinder of calcium phosphate and cartilage tissue produced by isolated swine articular chondrocytes seeded onto fibrin glue.

Methods: Swine articular chondrocytes were enzimatically isolated and seeded onto fibrin glue. Immediately before gel polymerization, the fibrin glue was placed in contact with the cylinders of calcium phosphate. The osteochondral composites were left in standard culture conditions for 1,3,6 weeks. At the end of experimental times the samples were macroscopically analysed and processed for histological evaluation.

Results: Preliminary data showed a macroscopically integrity of the osteochondral samples. Histology showed cartilage like tissue maturing within the fibrin glue scaffold.

Discussion: The results demonstrate that isolated chondrocytes, seeded onto fibrin glue, produce a cartilage-like matrix that integrates with a cylinder of calcium phosphate.

This tissue engineered osteochondral composite could represent a valuable model for further in vivo studies on the repair of osteochondral lesions.

Background: The aim of this study is to evaluate the efficacy of extracorpereal shock wave therapy (ESWT) in some of most frequent muscularskeletal pathologies.

Material and methods: From July to October 2004 310 patients were treated with ESWT, suffering from the following pathologies: 96 symptomatic calcific tendonitis of the shoulder, 53 symptomatic sub-acromial impingement, 48 humeral epichondylitis, 52 plantar fasciitis, 24 pertrochanteric bursitis, 15 Achilleous tendinopathy and 22 patellar tendinopathy.

Patients were evaluated clinically and instrumentally before the first application and at one and three months of follow-up. Three disability scales we utilized (NRS, Mcgill Pain Questionnaire e Chronic Pain Grade Questionnaire).

Results: We observed a reduction of the pain and an increase of the articular functionality in 83% of calcific tendonitis of the shoulder, in 55% of sub-acromial impingement, in 76% of epichondylitis, in 74% of palantar fasciitis, in 90% of pertrochanteric bursitis, in 82% of Achilleous tendinopathy and in 86% of patellar tendinopaty.

Discussion: The data confirm the therapy with ESWT is efficient in some of most frequent musculoskeletal pathologies, with variable outcome in the various pathologies under investigation.

Valgus deformity is a relatively common occurrence in rheumatic or degenerative disease of the tarsus. Frequently the angular deformity can exceed 25° ; in these situations dislocations of talo-calcaneal and/or talo-navicular joints can be observed. These conditions are usually progressive and affect the walking ability of the patient The goal of the study is to present a series of patients surgically treated in order to evaluate the best solutions and the problems of the surgical technique.

In the period 1996–2002, 22 patients were treated for significant valgus deformity of the rearfoot; 16 were affected by rheumatoid arthritis and six by a degenerative pathology. In all cases combined talo-navicular and talo-calcaneal arthrodesis was performed. In seven patients a bone graft was used to fill bone defects. The follow-up was 5.3 years. The results were evaluated using the AOFAS score for rearfoot; fusion was achieved in all but one case (talo-navicular joint). All patients were satisfied regarding subjective results (pain and function).

Combined arthrodesis of talo-calcaneal and talo-navicular joints is an effective method of treating significant valgus deformity of the hindfoot; fixation by screws for talo-calcaneal joint and by staples or screw for talo-navicular joint is the recommended method for synthesis.

The purpose of this work was to create an in vitro model of tissue-engineered cartilage structure produced by isolated swine articular chondrocytes, expanded in culture and seeded onto a biological scaffold.

Swine articular chondrocytes were enzymatically isolated from pig joints and expanded in monolayer culture. When confluence was reached, cells were resuspended and seeded in vitro onto biological collagen scaffolds for 3, 4 and 6 weeks. Samples were retrieved from the culture and analysed macroscopically and biomechanically by compressive test. Gross evaluation was performed by simple probing, sizing and weighing the samples at all time periods. A baseline of the values was also recorded at time 0. Then, samples were biomechanically tested by unconfined compression and shear tests. Finally, the samples were fixed in 4% paraformaldehyde and processed for histological evaluation. Some samples were stained with Safranin-o, and some others subjected to immunostaining analysis for type II collagen.

Upon retrieval, samples showed dimensional enlargement and mass increase over time and gross mechanic integrity by simple probing. A biomechanical test demonstrated an initial reduction in the values of compressive and shear parameters, followed by a consistent increase throughout the tested time points. Histology showed cartilage-like tissue maturing over time within the biological scaffold.

The results from this study demonstrate that isolated chondrocytes could be seeded onto a biological collagen scaffold, producing cartilage-like matrix with tissue-specific morphology and biomechanical integrity. This tissue-engineered cartilage structure is easily reproducible and it could represent a valuable model for studying the behaviour of different variables on the newly formed cartilage.

The purpose of this study was to assess the physical, biochemical and biomechanical properties of a cartilage matrix-chondrocyte-fibrin glue composite as biological tool for cartilage repair.

Chondrocytes were enzymatically isolated from pig joints and resuspended in fibrinogen solution. Articular cartilage was harvested from pig joints, chopped into small chips and lyophiliaed. Cartilage chips were rehydrated and mixed with the cell/fibrinogen solution and with thrombin, in order to form a fibrin glue gel composite with cells and chips (group A). Control composites were made from lyophilised cartilage chips assembled with fibrin glue, but not containing chondrocytes (group B). Other control groups included fibrin glue/chondrocyte specimens without cartilage chips (group C) and specimens made of the fibrin glue alone (group D). All samples were weighed and implanted into subcutaneous pouches of nude mice. Animals were sacrificed at 2 and 9 weeks. Samples were evaluated grossly and the final/initial mass ratio was calculated. Samples were evaluated histologically, biomechanically, and biochemically.

Upon retrieval, only the samples in experimental group A retained their original pre-implantation mass. Histological analysis showed newly formed cartilage matrix in the specimens from group A and C. Biomechanical analysis showed significantly higher modulus in experimental samples, with respect to the other groups at the latest time point. Analysis of hydraulic permeability showed significantly decreasing values for all groups throughout the experimental times and lowest values for the experimental samples of group A in the latest time point, although there was no statistically significant difference among the groups. Biochemical analysis demonstrated higher values in the latest time point for samples prepared with cells for water and GAG content, whereas highest values for hydroxyproline were recorded for samples assembled with cartilage chips. DNA analysis showed higher values of samples prepared with chondrocytes and fibrin glue and also an important increase in values of the samples made of fibrin glue only, indicating a possible host fibroblast growth inside the samples over time. This tissue-engineered composite presents cartilaginous appearance and biomechanical integrity after 9 weeks in vivo.