The osteo-inductive properties of bone matrix from rats pretreated with indomethacin

Insulin-like growth factor I increases bone formation in old or corticosteroid treated rats

We studied bone induction in subcutaneous implants of demineralized bone matrix with or without insulin-like growth factor I (IGF-I) in aged or corticosteroid-treated rats. Each rat carried one pair of implants, one control and one experiment implant, containing IGF-I dissolved in a hyaluronan solution for slow release. The rats were killed after 3 weeks and the results were evaluated by measuring the calcium content of implants. Young (6-7 weeks) and old (19-27 months) rats were used. A group of young rats was treated for 1 week with subcutaneous injections of 140 micrograms/kg dexamethasone daily. Old rats produced only approximately 1% as much bone as young rats. Local delivery of IGF-I did not increase bone formation in young rats. In old rats, bone formation was increased by IGF-I, 3000 ng/implant. Corticosteroids reduced bone formation in young rats. This effect was partially reversed by local administration of IGF-I.

Prevention of periarticular heterotopic ossification following total hip arthroplasty. Clinical experience with indomethacin and ibuprofen

Prophylactic treatment with indomethacin or ibuprofen to prevent periarticular heterotopic ossification (PHO) was investigated in a consecutive series of 200 total hip replacements (THR) performed for primary coxarthrosis in 170 patients. No widespread PHO (grades III and IV) occurred in 166 THR treated with indomethacin or ibuprofen from the 1st to the 21st postoperative day. Only one patient exhibited moderate (grade-II) ossification. In contrast, the incidence of PHO grades III and IV was found to be high (23%) in the 35 THR for which the patients did not receive prophylaxis according to intention. It was concluded that 3 weeks' postoperative treatment with indomethacin or ibuprofen is sufficient to prevent the development of clinically significant heterotopic ossification.