Clinical Trials and Management of Osteochondral Lesions.

Osteochondral lesions are frequent and important causes of pain and disability. These lesions are induced by traumatic injuries or by diseases that affect both the cartilage surface and the subchondral bone. Due to the limited cartilage ability to regenerate and self-repair, these lesions tend to gradually worsen and progress towards osteoarthritis. The clinical, social, and economic impact of the osteochondral lesions is impressive and although therapeutic alternatives are under discussion, a consensus is not yet been achieved. Over the previous decade, new strategies based on innovative tissue engineering approaches have been developed with promising results. However, in order those products reach the market and help the actual patient in an effective manner, there is still a lot of work to be done. The current state of the implications, clinical aspects, and available treatments for this pathology, as well as the ongoing preclinical and clinical trials are presented in this chapter.

In vitro and in vivo performance of methacrylated gellan gum hydrogel formulations for cartilage repair.

Methacrylated gellan gum (GGMA) formulation is proposed as a second-generation hydrogel for controlled delivery of cartilage-forming cells into focal chondral lesions, allowing immediate in situ retention of cells and 3D filling of lesion volume, such approach deemed compatible with an arthroscopic procedure. Formulation optimization was carried out in vitro using chondrocytes and adipose mesenchymal stromal/stem cells (ASCs). A proof-of-concept in vivo study was conducted using a rabbit model with induced chondral lesions. Outcomes were compared with microfracture or non-treated control. Three grading scores were used to evaluate tissue repair after 8 weeks by macroscopic, histological and immunohistochemical analysis. Intense collagen type II and low collagen type I gene and protein expression were achieved in vitro by the ASC + GGMA formulation, in light with development of healthy chondral tissue. In vivo, this formulation promoted significantly superior de novo cartilage formation compared with the non-treated group. Maintenance of chondral height and integration with native tissue was further accomplished. The physicochemical properties of the proposed GGMA hydrogel exhibited highly favorable characteristics and biological performance both in vitro and in vivo, positioning itself as an attractive xeno-free biomaterial to be used with chondrogenic cells for a cost-effective treatment of focal chondral lesions. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1987-1996, 2018.

Malignant Triton tumor: a rare cause of sciatic pain and foot drop.

Malignant peripheral nerve sheath tumors (MPNST) are very rare and are frequently localized in the buttocks, thigh, arm, or paraspinal region; one variant is the malignant Triton tumor, with rhabdomyosarcomatous differentiation. The authors present a challenging differential diagnosis of a sciatic pain and foot drop in a woman with history of lumbar disk herniation, which was found to be caused by a Triton tumor of the sciatic nerve. She underwent surgical excision, followed by radiation and chemotherapy. Malignant Triton tumor cases have rarely been described and reported in the literature. The recommended treatment is radical excision followed by high-dose radiotherapy and chemotherapy. The prognosis, although poor, depends on the location, grade, and completeness of surgical margins.

Os tumores malignos da bainha dos nervos periféricos (TMBNP) são muito raros e localizam-se mais frequentemente na região nadegueira, paraespinal, coxa ou braço; uma variante é o tumor de Triton maligno, com uma diferenciação rabdomiosarcomatosa. Apresentamos um diagnóstico diferencial desafiante de dor ciática e pé pendente em uma paciente com antecedentes de hérnia discal lombar, que se descobriu que era causada por um tumor de Triton do nervo ciático. A paciente foi submetida a excisão cirúrgica, seguida de radio e quimioterapia. Poucos casos de tumores de Triton malignos foram descritos e relatados na literatura. O tratamento recomendado é a excisão radical, seguida de radioterapia em alta dose e quimioterapia. O prognóstico, embora mau, depende da localização, do grau e das margens cirúrgicas da exérese.

Malignant Triton tumor: a rare cause of sciatic pain and foot drop / Tumor de Triton maligno: uma causa rara de dor ciática e pé pendente

ABSTRACT Malignant peripheral nerve sheath tumors (MPNST) are very rare and are frequently localized in the buttocks, thigh, arm, or paraspinal region; one variant is the malignant Triton tumor, with rhabdomyosarcomatous differentiation. The authors present a challenging differential diagnosis of a sciatic pain and foot drop in a woman with history of lumbar disk herniation, which was found to be caused by a Triton tumor of the sciatic nerve. She underwent surgical excision, followed by radiation and chemotherapy. Malignant Triton tumor cases have rarely been described and reported in the literature. The recommended treatment is radical excision followed by high-dose radiotherapy and chemotherapy. The prognosis, although poor, depends on the location, grade, and completeness of surgical margins.

RESUMO Os tumores malignos da bainha dos nervos periféricos (TMBNP) são muito raros e localizam-se mais frequentemente na região nadegueira, paraespinal, coxa ou braço; uma variante é o tumor de Triton maligno, com uma diferenciação rabdomiosarcomatosa. Apresentamos um diagnóstico diferencial desafiante de dor ciática e pé pendente em uma paciente com antecedentes de hérnia discal lombar, que se descobriu que era causada por um tumor de Triton do nervo ciático. A paciente foi submetida a excisão cirúrgica, seguida de radio e quimioterapia. Poucos casos de tumores de Triton malignos foram descritos e relatados na literatura. O tratamento recomendado é a excisão radical, seguida de radioterapia em alta dose e quimioterapia. O prognóstico, embora mau, depende da localização, do grau e das margens cirúrgicas da exérese.