Acute osteomyelitis (OM) and septic arthritis (SA) are two issues of great concern and debate for the pediatric orthopaedic surgeon.

Our purpose is to study the frequency of both diseases in the current years in comparison to the past, as well as other parameters that affect their progress such as time between the onset of the disease and the admission to the hospital, and pathogens that are found in pus and types of therapy.

Three periods were studied: Period A: years 1963–1975, Period B: years 1975–1983, Period C: years 2000–2005. In total, there were 451 patients suffering from OM and SA in Period A, 208 cases in Period B and 95 cases in Period C.

OM is found most often in the femur (A: 34.91%, B: 32.32%, C: 54.54%) and the tibia (A: 43.27%, B: 43.43%, C: 13.63%). SA is found mostly at the knee (A: 17.46%, B: 42.70%, C: 47.76%) and the hip (A: 50%, B: 37.50%, C: 41.79%) joints. A great percentage of patients in Period A (36.80%) are admitted to hospital very late (> 20 days from the onset of the disease); this number falls dramatically in Period C. There is, on the other hand, early admission to hospital (< 3 days) in period C (C: 74.73% versus A: 13.08%). No significant difference among age groups is apparent; 6–11 years of age are the most frequent. Staph. aureus has always been the most usual pathogen found in pus in the majority of cases. A great number of patients in Period A are admitted to hospital being already under antibiotic therapy (60.58%). This percentage falls in Period C (11.57%).

A decrease in the frequency of OM and SA in the recent years is obvious. Most of the patients are admitted early to hospital and due to this event, there is significant improvement concerning the complications from the diseases, in comparison to the past.