| Popis: |
The mechanical theory has received more attention than the neural hypothesis in orthopedic bibliography.2,12-20,23,25,27-29,36,42,48-50,60,61 Subchondral bone overload, with the consequent increment of the subchondral intraosseous pressure, is a direct result of patellofemoral malalignment (PFM). Subchondral bone overload can also be increased when the knee, with or without malalignment, is subject to an overuse or to a direct or indirect traumatism, as is very frequently seen in the practice of sports. Indeed, 49% of the patients in our surgical series suffered an indirect traumatism during sport activities before the onset of symptoms, and 5% of them suffered a direct hit.50 Furthermore, certain attitudes that are necessary to adopt in some sports (inherently) can contribute on the one hand to the increase of the subchondral bone overload due to the increment of the patellofemoral joint reaction (PFJR) force, and on the other hand to the increment of the Q angle. Sport is an important agent in the pathogenesis of the anterior knee pain syndrome and in the functional patellar instability as seen by the fact that 73% of our operated patients (unpublished data) used to play energetic sports (volleyball, basketball, handball, football, rhythmic gymnastics, or hockey) of level I (4–7 days a week of practice) or level II (1–3 days a week of practice) before the symptoms started. In addition to this, the degree of pain was related to the patient’s level of activity. It is worth remembering the undoubted relation between sport activities and the articular overuse concept. Overuse is defined in general terms as a repetitive microtrauma of a sufficient degree to overcome the regeneration capacity of the tissues.43 In all types of tissues, the microtraumatism, provoked by the application of repetitive tensions, produces microlesions in the collagen fibers, in addition to direct or indirect effects on the vascular supply. Additional factors in the genesis of the overuse syndromes include using the wrong techniques, training inadequately (including overtraining), and not employing the right equipment. |
