Will the Kaplan Fiber Complex Be the ''New Anterolateral Ligament''? Insights from Direct Surgical Exploration in the Context of ACL Injury and Reconstruction

According to the most popular scientific literature database in 2022, nearly 20 papers mentioning the "Kaplan Fiber" complex have been published in the last 2 years, highlighting the role of this anatomical structure in the context of anterior cruciate ligament tear [...]

The Use of 3D-Printed Custom-Made Implants as an Attractive Potential Alternative to the Treatment of Segmental Bone Loss in Foot and Ankle

The treatment of segmental tibial and ankle bone loss after radical surgery for chronic osteomyelitis is one of the most challenging problems encountered by orthopaedic surgeons [...]

Hallux rigidus: current concepts review and treatment algorithm with special focus on interposition arthroplasty

Hallux rigidus represents a surgical challenge, with a multitude of possible surgical options, but with no ideal procedures.  The propose of this paper was to review the actual knowledge on the operative techniques, paying particular attention to the evolution of interposition arthroplasties, as an alternative to arthrodesis and prosthesis in the advanced stages of the disease

RANKL-RANK-OPG Pathway in Charcot Diabetic Foot: Pathophysiology and Clinical-Therapeutic Implications

Charcot Foot (CF), part of a broader condition known as Charcot Neuro-Osteoarthropathy (CNO), is characterized by neuropathic arthropathy with a progressive alteration of the foot. CNO is one of the most devastating complications in patients with diabetes mellitus and peripheral neuropathy but can also be caused by neurological or infectious diseases. The pathogenesis is multifactorial; many studies have demonstrated the central role of inflammation and the Receptor Activator of NF-kappa B ligand (RANKL)-Receptor Activator of NF-kappa B (RANK)-Osteoprotegerin (OPG) pathway in the acute phase of the disease, resulting in the serum overexpression of RANKL. This overexpression and activation of this signal lead to increased osteoclast activity and osteolysis, which is a prelude to bone destruction. The aim of this narrative review is to analyze this signaling pathway in bone remodeling, and in CF in particular, to highlight its clinical aspects and possible therapeutic implications of targeting drugs at different levels of the pathway. Drugs that act at different levels in this pathway are anti-RANKL monoclonal antibodies (Denosumab), bisphosphonates (BP), and calcitonin. The literature review showed encouraging data on treatment with Denosumab, although in a few studies and in small sample sizes. In contrast, BPs have been re-evaluated in recent years in relation to the high possibility of side effects, while calcitonin has shown little efficacy on CNO

Custom-Made Devices Represent a Promising Tool to Increase Correction Accuracy of High Tibial Osteotomy: A Systematic Review of the Literature and Presentation of Pilot Cases with a New 3D-Printed System

Background: The accuracy of the coronal alignment corrections using conventional high tibial osteotomy (HTO) falls short, and multiplanar deformities of the tibia require consideration of both the coronal and sagittal planes. Patient-specific instrumentations have been introduced to improve the control of the correction. Clear evidence about customized devices for HTO and their correction accuracy lacks. Methods: The databases PUBMED and EMBASE were systematically screened for human and cadaveric studies about the use of customized devices for high tibial osteotomy and their outcomes concerning correction accuracy. Furthermore, a 3D-printed customized system for valgus HTO with three pilot cases at one-year follow-up was presented. Results: 28 studies were included. The most commonly used custom-made devices for HTO were found to be cutting guides. Reported differences between the achieved and targeted correction of hip-knee-ankle angle and the posterior tibial slope were 3 degrees or under. The three pilot cases that underwent personalized HTO with a new 3D-printed device presented satisfactory alignment and clinical outcomes at one-year follow-up. Conclusion: The available patient-specific devices described in the literature, including the one used in the preliminary cases of the current study, showed promising results in increasing the accuracy of correction in HTO procedure

Mobile-Bearing Total Ankle Replacement In Vivo Kinematic Assessment: A Prospective Study Protocol

Total ankle prosthesis as a surgical solution in the case of end-stage osteoarthritis has seen a considerable increase in the last two decades. This study protocol arises from the need to understand the in vivo kinematics of mobile-bearing, flat tibial component total ankle replacement, evaluating the real range of motion and the reciprocal relationships between the components during normal motor tasks through the use of model-based radio-stereometric analysis (MB-RSA). In addition, pre- and post-operative evaluation of walking kinematics with inertial motion sensors, proprioception through a dedicated workstation, and clinical outcomes are discussed. We expect that based on our study protocol researchers will be able to improve future prosthetic designs and validate the setup of MB-RSA, as well as to understand "how an ankle prosthesis moves" once implanted in the patient

Custom-Made Implants in Ankle Bone Loss: A Retrospective Assessment of Reconstruction/Arthrodesis in Sequelae of Septic Non-Union of the Tibial Pilon

Background and Objectives: Treating segmental tibial and ankle bone loss after radical surgery for chronic osteomyelitis is one of the most challenging problems encountered by orthopaedic surgeons. Open tibia and ankle fractures occur with an incidence of 3.4 per 100,000 and 1.6 per 100,000, respectively, and there is a high propensity of developing fracture-related infection with associated chronic osteomyelitis in patients. Segmental tibial and ankle bone loss have recently received new and improved treatments. Materials and Methods: Above all, 3D printing allows for the customization of implants based on the anatomy of each patient, using a personalized process through the layer-by-layer deposition of materials. Results: This article presents different cases from the authors' experience. Specifically, four patients suffered tibia and ankle fractures and after radical surgery for chronic osteomyelitis combined with high-performance antibiotic therapy underwent ankle reconstruction/arthrodesis with custom-made tibial spacers. Conclusions: Thanks to 3D-printed patient-specific devices, it is possible to perform surgical procedures that, for anatomical reasons, would have been impossible otherwise. Moreover, an improvement in overall functionality and an important reduction in pain were shown in the last follow-up in all patients

Woven bone formation and mineralization by rat mesenchymal stromal cells imply increased expression of the intermediate filament desmin

BackgroundDisordered and hypomineralized woven bone formation by dysfunctional mesenchymal stromal cells (MSCs) characterize delayed fracture healing and endocrine –metabolic bone disorders like fibrous dysplasia and Paget disease of bone. To shed light on molecular players in osteoblast differentiation, woven bone formation, and mineralization by MSCs we looked at the intermediate filament desmin (DES) during the skeletogenic commitment of rat bone marrow MSCs (rBMSCs), where its bone-related action remains elusive.ResultsMonolayer cultures of immunophenotypically- and morphologically - characterized, adult male rBMSCs showed co-localization of desmin (DES) with vimentin, F-actin, and runx2 in all cell morphotypes, each contributing to sparse and dense colonies. Proteomic analysis of these cells revealed a topologically-relevant interactome, focused on cytoskeletal and related enzymes//chaperone/signalling molecules linking DES to runx2 and alkaline phosphatase (ALP). Osteogenic differentiation led to mineralized woven bone nodules confined to dense colonies, significantly smaller and more circular with respect to controls. It significantly increased also colony-forming efficiency and the number of DES-immunoreactive dense colonies, and immunostaining of co-localized DES/runx-2 and DES/ALP. These data confirmed pre-osteoblastic and osteoblastic differentiation, woven bone formation, and mineralization, supporting DES as a player in the molecular pathway leading to the osteogenic fate of rBMSCs.ConclusionImmunocytochemical and morphometric studies coupled with proteomic and bioinformatic analysis support the concept that DES may act as an upstream signal for the skeletogenic commitment of rBMSCs. Thus, we suggest that altered metabolism of osteoblasts, woven bone, and mineralization by dysfunctional BMSCs might early be revealed by changes in DES expression//levels. Non-union fractures and endocrine – metabolic bone disorders like fibrous dysplasia and Paget disease of bone might take advantage of this molecular evidence for their early diagnosis and follow-up

Reconstructive Surgery and Joint-Sparing Surgery in Valgus and Varus Ankle Deformities: A Comprehensive Review

Osteoarthritis (OA) of the ankle affects about 1% of the world’s adult population, causing an important impact on patient lives and health systems. Most patients with ankle OA can show an asymmetrical wear pattern with a predominant degeneration of the medial or the lateral portion of the joint. To avoid more invasive ankle joint sacrificing procedures, joint realignment surgery has been developed to restore the anatomy of the joints with asymmetric early OA and to improve the joint biomechanics and symptoms of the patients. This narrative, comprehensive, all-embracing review of the literature has the aim to describe the current concepts of joint preserving and reconstructive surgery in the treatment of the valgus and varus ankle early OA, through an original iconography and clear indications and technical notes

Comprehensive kinematic evaluation, in vivo and under weight-bearing, of a 3-component total ankle replacement.

Nonostante le importanti ricadute che gli impianti protesici di caviglia hanno nella qualità della vita dei pazienti che si sottopongono ad intervento di sostituzione articolare, le reali proprietà biomeccaniche e cinematiche in-vivo e sotto carico degli impianti protesici sono state scarsamente studiate e descritte in letteratura. Lo scopo di questa trattazione è quella di valutare la cinematica protesica complessiva, in vivo, attraverso l’utilizzo dell’Analisi Radiostereometrica model-based (MB-RSA) e di ulteriori metodiche clinico-strumentali. La valutazione cinematica è stata permessa dall’analisi della posizione degli impianti attraverso la MB-RSA. Tra gli obiettivi secondari, i pazienti sono stati valutati clinicamente mediante AOFAS Ankle-Hindfoot score e SF-36, mediante full-body gait analysis con sensori inerziali e valutazione posturale-stabilometrica mediante Y Balance Test e workstation dedicata Delos DPPS. I pazienti sottoposti ad iter completo con valutazione clinica e strumentale a fine follow-up sono risultati 18 (2 drop-out). Il ROM complessivo a catena cinetica chiusa ha evidenziato una dorsi-plantarflessione complessiva media di 19.84°. Gli score clinici hanno mostrato tutti un netto miglioramento nel post-operatorio. La gait analysis ha evidenziato uno schema del passo composto dai tre principali spike e compatibile con schemi fisiologici. Dal punto di vista cinematico, i risultati angolari MB-RSA ricavati durante questo lavoro di tesi evidenziano tutti e 6 i gradi di libertà, dato coerente con la mobilità di una caviglia nativa. Valori di articolarità differenti sono stati registrati mediante sensori inerziali. Infine, in una valutazione cinematica complessiva, le possibili implicazioni sul bilanciamento posturale e propriocettivo presente nelle caviglie artrosiche e successivamente sottoposte a sostituzione protesica totale sono ampiamente descritte e discusse. I dati raccolti in questo lavoro di tesi rappresentano il risultato di una valutazione cinematica complessiva, e potranno aiutare a definire una tipologia di soggetto artrosico in cui i risultati siano verosimilmente migliori ed eventualmente a migliorare design e strumentari futuri.Despite the important impact that ankle prosthetic implants have on the quality of life of patients undergoing joint replacement surgery, the real biomechanical and kinematic properties in-vivo of prosthetic implants have been poorly studied and described in the literature. The purpose of this project is to evaluate the overall prosthetic kinematics, in vivo, through the use of model-based radiostereometric analysis (MB-RSA) and further clinical-instrumental methods. The kinematic evaluation was enabled by the analysis of the position of the systems through the MB-RSA. Among the secondary objectives, patients were clinically evaluated using AOFAS Ankle-Hindfoot score and SF-36, through full-body gait analysis with inertial sensors and postural-stabilometric evaluation using Y Balance Test and dedicated Delos DPPS workstation. Patients undergone a complete procedure with clinical and instrumental evaluation at the end of the follow-up were 18 (2 drop-outs). The total ROM with closed kinetic chain showed an average overall dorsi-plantarflexion of 19.84°. Clinical scores all showed a marked improvement in post-op. The gait analysis showed a step pattern composed of the three main spikes and compatible with physiological patterns. From the kinematic point of view, the angular MB-RSA results obtained during this thesis work highlight all 6 degrees of freedom, given consistent with the mobility of a native ankle. Different joint values were recorded by inertial sensors. Finally, in an overall kinematic assessment, the possible implications on the postural and proprioceptive balance present in osteoarthritic ankles and subsequently subjected to total prosthetic replacement are widely described and discussed. The data collected are the result of an overall kinematic assessment, and may help to define a type of osteoarthritic subject in which the results are likely to be better and possibly to improve future design and instrumentation