The repeated attempts of surgical treatment of the peri-articular non-unions inevitably lead to extended vascular isolation. We can also often þnd, in various degrees, stiffness, instability, axial deviations, bone mass loss, vicious metaphyseal cal or pathological curving of dyaphysis.

The hinged prostheses can prove their selves very useful for the peri-articular non-unions of the knee, being able to replace the articulation completely. They are seldom necessary in daily practice but they proved very useful in these osteopenic cases of Ç recalcitrant non-unions È. having undergone more than three interventions.

In this group of patients (4 cases), the Maidstone type prostheses allowed an early support and a more aggressive rehabilitation, with good functional results (followed for an average of 42 months). After a long period of almost total invalidity, all have recovered a normal social life in spite of a certain loss in the mobility of the knee.

On the contrary, in the peri-articular pseudarthroses of the elbow, with intact capsulo-ligamentary elements, the Kudo prostheses, preserving a natural articular stability controlled by the proprioceptors, are indicated in comparison with the hinged prostheses. The hinged implant Solar (2 cases) became however essential for the cases with a loss of osseous mass which included the capsulo-ligamentary mechanism.

For the trochanteric non-unions, the requirements lean especially on the possibility of the recovery length and position of the pelvic limb; we had a great success with the Kent type implants.

We can consider these types of arthroplasty as salvage procedures, able to recover these patients socially, however accepting a certain loss of the articular function.