[Bloodless treatment of patellar instability; author's experience].

The Authors discuss the cases treated in the Fatebenefratelli Hospital in Erba in the period 1975-80 and propose strengthening of the quadriceps muscle as first treatment of knee cap instability.

[Posterolateral vertebral arthrodesis (author's transl)].

The authors review a number of more or less original technics of posterolateral vertebral arthrodesis, and report published results relative to intersomatic, posterior, and posterolateral arthrodesis. To this they add a presentation of their own cases treated by posterolateral arthrodesis, noting that this method is not unduly difficult to perform and gives good results in a high percentage of cases.