Dynamic ROM Via Gait Analysis and 3D Fluoroscopy in THA With Different Head Diameters

Pain and reduced function are the most common symptoms of coxarthritis. Pain relief and normal range of motion (ROM) restoration are the objectives of a Total Hip Arthroplasty (THA) procedure. It is recognized that increased head-neck ratio results in increased ROM due to the fact that prosthetic impingement between neck and acetabular liner occurs with wider arcs of motion. This head-neck ratio has been investigated extensively only in vitro (on cadavers or sawbones) or using mathematical modeling in computer simulations. These studies are limited by the lack of soft tissues and muscle activations in the models. This study will clinically assess the effect of prosthetic head diameter on patient capability of performing movements which require extreme arcs of motion of the hip joint. Therefore, the research questions are: * What role do soft tissues play in limiting ROM? * Can prosthetic impingement really occur in a well positioned THA? * Can a bigger head diameter alone reduce the risk of impingement?

Sex

All

Minimum age

35 Years

Maximum age

55 Years

Inclusion Criteria:

* Patients with unilateral primary or secondary hip arthrosis indicated for THA;
* Men and female, age between 35 and 55 years old;
* BMI smaller than 30;
* Patients able to understand the protocol and to sign the informed consent.

Exclusion Criteria:

* Child-bearing female;
* Patients with also controlateral hip arthritis;
* Neurological patients, because of possible alteration of neuro-muscular control of the replaced hip;
* Patients treated with joint replacement at any other lower limb articulation