[Refixation of osteochondral fragments with resorbable polylactid implants : Long-term clincal and MRI results]

[Osteochondral fractures in childhood and adolescence]

BACKGROUND

Osteochondral fractures (OCF) are traumatic shearing injuries to portions of cartilage and bone. The most common cause is patellar dislocation, with the main localisation being the medial patellar facet and the lateral femoral condyle. They can occur in all age groups.

DIAGNOSIS

Clinically, there is a painful knee joint effusion (haemarthrosis) with a "dancing patella". This is usually accompanied by restricted movement and/or a locking phenomenon. In addition to the standard X‑ray of the knee in three planes (lateral, anterior-posterior and tangential patella), an MRI should be performed promptly in the case of haemarthrosis and suspicious symptoms, as concomitant injuries are present in up to 70% of cases.

TREATMENT

The aim of treatment is to restore joint congruence in order to prevent the risk of secondary osteoarthritis. Small chondral and stable osteochondral fractures can be treated conservatively. Surgery is indicated for all other OCFs. In addition to refixation with various materials (bioresorbable screws, bone plugs, suture material and Kirschner wires), cartilage regeneration procedures (AMIC, MACI, OAT, etc.) are available for late diagnosed or non-refixable fragments. However, the number of cases is small.

CONCLUSION

Osteochondral fractures are rare injuries in children and adolescents. Prompt MRI is recommended for diagnosis in cases of suspected OCF. Refixation is the preferred treatment method, with bioresorbable implants showing promising results in reducing the need for additional surgery. The risk of secondary osteoarthritis can be reduced with regular treatment.

Ankle Sprains in Athletes: Current Epidemiological, Clinical and Imaging Trends

Purpose

Ankle injuries are frequent sports injuries. Despite optimizing treatment strategies during recent years, the percentage of chronification following an ankle sprain remains high. The purpose of this review article is, to highlight current epidemiological, clinical and novel advanced cross-sectional imaging trends that may help to evaluate ankle sprain injuries.

Methods

Systematic PubMed literature research. Identification and review of studies (i) analyzing and describing ankle sprain and (ii) focusing on advanced cross-sectional imaging techniques at the ankle.

Results

The ankle is one of the most frequently injured body parts in sports. During the COVID-19 pandemic, there was a change in sporting behavior and sports injuries. Ankle sprains account for about 16-40% of the sports-related injuries. Novel cross-sectional imaging techniques, including Compressed Sensing MRI, 3D MRI, ankle MRI with traction or plantarflexion-supination, quantitative MRI, CT-like MRI, CT arthrography, weight-bearing cone beam CT, dual-energy CT, photon-counting CT, and projection-based metal artifact reduction CT may be introduced for detection and evaluation of specific pathologies after ankle injury. While simple ankle sprains are generally treated conservatively, unstable syndesmotic injuries may undergo stabilization using suture-button-fixation. Minced cartilage implantation is a novel cartilage repair technique for osteochondral defects at the ankle.

Conclusion

Applications and advantages of different cross-sectional imaging techniques at the ankle are highlighted. In a personalized approach, optimal imaging techniques may be chosen that best detect and delineate structural ankle injuries in athletes.

[Surgical treatment of focal cartilage defects in the knee : Indications, techniques, modifications and results]

The treatment strategies for focal cartilage damage in the knee are multifarious. For established procedures, such as microfracturing (MFX), autologous matrix-induced chondrogenesis (AMIC), osteochondral transplantation (OCT) and autologous chondrocyte transplantation (ACT), well-founded, partly comparative long-term studies and overlapping size-dependent differential indications are available. Innovative cell sources, the utilization of biological scaffolds as well as biologic agents and various combinations, have recently become the focus of scientific attention; however, high regulatory demands are restricting their use in Germany. The success of every procedure is dependent on the appropriate indications, the treatment of comorbidities, such as axis deviations or ligamentous instability, the surgeon's experience and an adequate follow-up treatment.

[Surgical treatment of focal cartilage defects in the knee : Indications, techniques, modifications and results]

The treatment strategies for focal cartilage damage in the knee are multifarious. For established procedures, such as microfracturing (MFX), autologous matrix-induced chondrogenesis (AMIC), osteochondral transplantation (OCT) and autologous chondrocyte transplantation (ACT), well-founded, partly comparative long-term studies and overlapping size-dependent differential indications are available. Innovative cell sources, the utilization of biological scaffolds as well as biologic agents and various combinations, have recently become the focus of scientific attention; however, high regulatory demands are restricting their use in Germany. The success of every procedure is dependent on the appropriate indications, the treatment of comorbidities, such as axis deviations or ligamentous instability, the surgeon's experience and an adequate follow-up treatment.

Reconstruction of Large Osteochondral Lesions in the Knee: Focus on Fixation Techniques

Large (>3 cm²), focal osteochondral lesions (OCL) may result in poor functional outcomes and early secondary osteoarthritis of the knee. The surgical management of these OCL remains challenging. The treatment strategy must be tailored to various aspects, including lesion-specific (e.g., size, location, chronicity), joint-specific (e.g., instability, limb alignment, meniscal status), and patient-specific factors (e.g., age, activity level, comorbidities). Simple chondroplasty and bone marrow stimulation (BMS) techniques should be reserved for smaller lesions, as they only realize midterm clinical benefits, related to inferior wear characteristics of the induced fibrocartilage (type I collagen). Therefore, much attention has been focused on surgical restoration with hyaline cartilage (type II collagen), based on chondrocyte transplantation and matrix-assisted autologous chondrocyte implantation (MACI). Limited graft availability, staged procedures (MACI), and high treatment costs are limitations of these techniques. However, acute traumatic OCL of the femoral condyles and patellofemoral joint may also be suitable for preservation by surgical fixation. Early detection of the fragment facilitates primary repair with internal fixation. The surgical repair of the articular surface may offer promising clinical and cost-effective benefits as a first-line therapy but remains under-investigated and potentially under-utilized. As a unique characteristic, the fixation technique allows the anatomic restoration of the hyaline articular surface with native cartilage and the repair of the subchondral bone. In this manuscript, we present a case series of large OCL around the knee that were preserved by surgical fixation. Furthermore, various implants and techniques reported for this procedure are reviewed.

Autologe Chondrozytentransplantation nach penetrierender Messerstichverletzung am Kniegelenk

Die penetrierende Kniegelenkverletzung ist ein seltenes Trauma, welches jedoch nicht unterschätzt werden darf. In der Regel besteht die Indikation zur zeitnahen operativen Versorgung. Dieser Fallbericht handelt von einem 17-jährigen Patienten, der durch einen Messerstich eine Knorpelverletzung der lateralen Femurkondyle erlitt. Es folgte die Gelenkspülung mit Bergung des Knorpelflakes und endgültiger Versorgung mittels autologer Chondrozytentransplantation. Die Gewinnung von Knorpelzellen aus dem Flake unterblieb aufgrund des Risikos einer Keimbesiedlung sowie des Qualitätsverlustes der Chondrozyten.