The effect of impaction and a bioceramic coating on bone ingrowth in porous titanium particles

Contains fulltext : 98422.pdf (publisher's version ) (Open Access)BACKGROUND AND PURPOSE: Porous titanium (Ti) particles can be impacted like cancellous allograft bone particles, and may therefore be used as bone substitute in impaction grafting. We evaluated the effect of impaction and of a thin silicated biphasic calcium phosphate coating on osteoconduction by Ti particles. METHODS: The bone conduction chamber of Aspenberg was used in goats and filled with various groups of coated or uncoated small Ti particles (diameter 1.0-1.4 mm). Impacted allograft bone particles and empty chambers were used in control groups. Fluorochromes were administered at 4, 8, and 12 weeks. Maximum bone ingrowth distance was evaluated by histomorphometric analysis. RESULTS: Histology of Ti particle graft cylinders showed a dense matrix with narrow inter-particle and intra-particle pores (< 100 mum), occluding the lumen of the bone chamber. Bone ingrowth distances gradually increased with time in all groups. Maximum bone ingrowth distance was higher in originally empty chambers than those with allograft bone particles (p = 0.01) and Ti particles (p < 0.001). Maximum bone ingrowth in allograft bone particles was higher than in all Ti groups (p </= 0.001). Impaction reduced osteoconduction and the coating partially compensated for the negative effect of impaction, but these differences were not statistically significant. No osteolytic reactions were found. INTERPRETATION: Osteoconduction in the bone conduction chamber was reduced more by the insertion of small Ti particles than by insertion of small allograft bone particles. The osteoconductive potential of porous Ti particles should be studied further with larger-sized particles, which may allow bone ingrowth after impaction through larger inter-particle pores

Tratamento da pseudo-artrose do terço distal do rádio Treatment of nounion in the third distal of the radio

Os autores apresentaram um estudo prospectivo de quatro pacientes portadores de pseudo-artrose no terço distal do rádio. Dois eram do sexo feminino e dois do masculino, com idade média de 42,5 anos. O diagnóstico de pseudo-artrose foi realizado em média com 5,3 meses após o trauma. Um paciente apresentava, como antecedente mórbido pessoal, epilepsia e osteoporose, outros dois relataram tabagismo e obesidade e o quarto, fratura exposta. O tratamento consistiu de osteossíntese interna e enxertia com osso autógeno. Todos foram submetidos à avaliação clínica pré e pós-operatória quanto à força de preensão palmar e arco de movimentos do punho. Houve 100% de consolidação das fraturas do terço distal do rádio em pseudo-artrose e retorno dos pacientes às atividades profissionais.<br>The authors presented a prospective study of four patients presenting pseudarthrosis at the distal third of the radius. Two patients were females and two were males, aged between 29 and 51 years with a mean age of 42.5 year old. The diagnosis of pseudarthrosis was provided within an average of 5.3 months after trauma. One patient presented as personal morbid history, epilepsy and osteoporosis, two patients were smokers and obese, and the fourth had an open fracture. The treatment consisted of internal osteosynthesis and autogenous bone graft. All patients were submitted to pre- and post operative clinical evaluation for palmar holding force and movement arch of the wrist. 100% of the radius distal-third fractures in pseudarthrosis have been united, with all patients returning to their respective professional activities