[Postural control strategy in patients with anterior cruciate ligament deficiency].

UNLABELLED: Dysfunction of the knee joint caused by injury of the anterior cruciate ligament is associated not only with mechanical joint destabilization but also damage of receptors in the ligament responsible for joint proprioception. Sensory disorders associated with damage of receptors in the ligaments may produce abnormalities in the posture control. The study aimed at evaluating postural control strategy in patients with chronic anterior cruciate ligament deficiency and determining a relationship between clinical assessment, subjective evaluation of knee joint functioning, and type of postural control.

MATERIAL AND METHODS: Postural control with dynamic and static Riva test in one-legged position was assessed in 46 patients (6 women and 40 men), aged between 15 and 52 years (mean 32 years), in whom damage of the anterior cruciate ligament was diagnosed clinically and/or radiologically. Diagnosis was confirmed arthroscopically in all cases. Clinical evaluation was made with the aid of two subjective scales of knee ailments: Lysholm knee scale and subjective knee evaluation form IKDC 2000. Arthrometer Rolimeter by Aircast was used to measure the difference between lower limbs in anterior knee laxity during "anterior drawer" test and Lachman's test. The way of visual proprioceptive control was assessed with both dynamic (DRT) and static (SRT) Riva tests in monopodalic stance. Tests were performed with the DELOS Postural Proprioceptive System (DELOS s.r.l., Corso Lecce, Torino, Italy) in the biomechanical evaluation laboratory at Rehasport Clinic in Poznań.

CONCLUSIONS: Strategy of the postural control in both dynamic and static Riva test does not allow differentiating ACL deficient leg from the mechanically stable leg. The obtained results of postural control in dynamic and static Riva test confirm significant value of knee joint mechanical stability for preservation its functional stability. Knee joint extension (hyperextension) may be one of mechanisms maintaining functional knee joint stability.