The Effect of Intrinsic Focus on Gait Cycle and the Possible Confounding Effect of Noise in Patients With Knee Osteoarthritis

Patients with knee osteoarthritis may develop an antalgic gait over time due to pain in the knee, characterized by a decrease in the stance phase and stride length on the painful side. Gait asymmetry, which may lead to different musculoskeletal problems in the future, is observed in the patients. Gait symmetry can be achieved with gait retraining, and effective focus is required during training.

In the literature, there are many studies of the positive effects of white noise on focusing, but there are also studies that report that it reduces focusing.

Today, exercise training is usually performed in rehabilitation units or on treadmills. As there are important differences between walking on a treadmill and walking outdoors in terms of noise, uneven ground and visual stimuli, the place where walking training is performed does not reflect the outdoor environment.

It was aimed to investigate the effect of internal focusing on gait cycle and the effect of white noise and environmental sound on internal focusing in patients with knee osteoarthritis

A total of 40 patients between the ages of 50 and 75 years, who were admitted to the outpatient clinic of Gazi University Faculty of Medicine, Department of Physical Medicine and Rehabilitation or hospitalized in the ward and diagnosed with knee osteoarthritis according to ACR knee osteoarthritis criteria and had a Kellgren Lawrence staging of at least 2, were included.

The demographic data of the patients who were evaluated with the Hearing Handicap Inventory for the Elderly Screening Version (HHIE-S) and had adequate hearing level were recorded, bilateral true leg lengths were measured and detailed knee examinations were performed. Lequesne Knee Osteoarthritis Severity Index, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Lower Extremity Functional Scale (LEFS), 30 Second Sit to Stand Test and Timed Up and Go Test were applied to the patients who met the inclusion and exclusion criteria.

Patients walked at a speed of 0.40-0.45 m/s on a treadmill (Biodex Gait Trainer) where gait parameters were collected. Each patient walked at a constant speed for three minutes each in the baseline (without any instruction or sound), intrinsic focus (focusing on ensuring equal step lengths and step durations on both sides and symmetry between both steps), white noise (intrinsic focus accompanied by white noise) and environmental sound (intrinsic focus accompanied by environmental sound) conditions. After walking in each condition, gait parameters ( average step cycle, average step length, percentage of step length variability, percentage of left/right side stepping time and ambulation index) were recorded. The User Experience Questionnaire Short Form was adapted for our study to assess patients' experiences during intrinsically focused walking in white noise and environmental sound conditions. Patients were asked to rate their walking periods in white noise and environmental sound conditions in terms of inhibiting-supportive, inefficient-efficient, complex-simple, confusing-clear, boring-exciting, uninteresting-interesting, traditional-unique, and familiar-unusual characteristics.

Eligibility Criteria:
Inclusion Criteria:

* Stable general condition
* Good cooperation
* Diagnosed with knee osteoarthritis according to ACR criteria
* At least stage 2 unilateral or bilateral knee osteoarthritis according to Kellgren Lawrence staging
* Individuals \>50 years of age

Exclusion Criteria:

* Hearing Impairment Scale ≥ 26
* Presence of a neurological, cardiac or orthopedic pathology that prevents walking
* The presence of another pathology other than knee osteoarthritis that affects the knee and causes pain
* Presence of diseases such as osteoarthritis, gout, rheumatoid arthritis affecting other joints in the lower extremity