One-year follow-up data from the German Cartilage Registry (KnorpelRegister DGOU) in the treatment of chondral and osteochondral defects of the talus

INTRODUCTION

Chondral and osteochondral lesions of the talus (OLTs) remain a challenging issue with numerous operative treatments proposed to date. The aim of this study was to evaluate 1-year follow-up data in the German Cartilage Registry (KnorpelRegister DGOU).

METHODS

Among 401 patients in the database, 114 patients with a complete 1-year Foot and Ankle Outcome (FAOS) score for subscale Pain as the primary variable were included. A total of 12 different surgical treatments were performed. However, 8 techniques were carried out in negligible numbers of patients (n = 1-3), leaving 89 patients treated with the following techniques: arthroscopic antegrade bone marrow stimulation (group A; n = 32), autologous chondrocyte implantation with autologous cancellous bone grafting (group B; n = 9), matrix-augmented bone marrow stimulation (group C; n = 22), and matrix-augmented bone marrow stimulation with autologous cancellous bone grafting (group D; n = 26). Group differences and possible influencing variables such as age and sex were evaluated. Level of significance was set at p < 0.05 for all statistical tests.

RESULTS

All four treatment groups showed significant improvement of the FAOS scores at 1 year postoperatively compared with their preoperative scores. No significant differences were found with respect to score changes among the groups. A positive correlation between FAOS subscale Pain improvement and defect size volume and negative correlations between increasing age and FAOS subscales Sports/Rec and QoL were found. Concomitant ankle stabilization led to greater improvement in FAOS subscales Symptoms and ADL than in patients with no stabilization. FAOS subscale Pain showed greater improvement in women than in men.

CONCLUSION

All analyzed treatment options were effective for treatment of OLTs. In particular, large defects appeared to benefit from treatment. In the presence of concomitant ankle instability, a stabilizing procedure appeared to have a positive impact on the outcome.

[Animal model for the study of the biocompatibility of root filling materials]

The aim of this study was to investigate the influence of different pins usually used for intraoperative root filling on periapical bone healing. In a specially designed animal experiment it was possible to evaluate biocompatibility simultaneously with the influence of varying materials on bone regeneration in standardized defects. Bioincompatible silver, acrylate and gutta percha root filling delay and impede bone regeneration. Biocompatible aluminium oxide ceramic and titanium pins do not have any influences on spontaneous bone regeneration. Reducing the defect, however, they do improve the conditions for complete bony regeneration.

[Physiological and cell biological characterization of the protease producer Thermoactinomyces vulgaris during prolonged culture in a stirred fermenter]

The physiological behaviour of Thermoactinomyces vulgaris - producing a thermostable serine-protease - was analyzed during fermentation. During 38 h the consumption of nutrients and oxygen as well as the rates of macromolecular and protease synthesis were measured. The morphological and ultrastructural changes of the mycelia were also studied. The mycelia grew exponentially for about 5 hours. After a short lag and a second slower growth phase, growth continued about linearly until the end, as was indicated by a constant rate of incorporation of labelled thymidine. However, at the same time a changing portion of hyphae - up to 45% - underwent lysis. According to the changing ratio of growing and lysing material, regarding the physiological activity of the culture the fermentation process could be divided into 4 periods. The formation of the protease started at the transition to the slow growth phase and continued linearly. The ability to produce the protease was attributed to a mycelium being formed after the shift down caused by limitation of supply of utilizable nitrogen compounds. The end of protease production 10 h later was correlated to a drastic decrease of the respiratory activity of the mycelia, probably caused by exhaustion of easily utilizable carbohydrates.