To satisfy the large range of femoral shapes and sizes encountered during the course of orthopedic surgery, it would be necessary to have a exceedingly large range of prosthetic sizes. Therefore, about 1980, the concept of interchangeability of heads was developed from the original monoblock implants. In fact, prosthetic modulariy means the ability to use interchangeable components to restore optimum anatomical conditions (e.g. length, anteversion, offset etc). The first form of modularity was later further developed by an even more innovative policy which attributes specific "roles" to each component of the implant whether cemented or press-fitted. This enables the elements to adapt to the anatomy in an optimal manner. It is clear that, in this context, the modular neck becomes the "pivot" necessary for the entire prosthetic implant, the connection that allows the stem and cup to adapt in the best possible manner.
The Modular Neck
The modular neck is the adapter between the stem and cup necessary to restore the anatomical-physiological conditions such as off-set, muscular tension, center of rotation, position of the articular head and, last but not least, the correct distribution of loads on the implant.
Modular necks are available in two lengths and six angles. Along with five different head sizes, this totalt in a record of 110 different angles for perfect fit!
For more information on the modular necks such as brochures, articles, video etc., please contact Ortotech directly.