The Validity and Reliability of an Improved Paper Grasping Test for Parkinson's Disease

Parkinson's disease is one of the most significant neurodegenerative disorders causing disability worldwide. It is characterized by progressive loss of dopaminergic neurons in the substantia nigra, leading to motor symptoms such as bradykinesia, rigidity, tremor, postural instability, and gait disturbances. Symptoms vary depending on disease stage and the affected neural pathways. Common symptoms observed in individuals with Parkinson's disease include muscle weakness, reduced upper limb function, gait difficulties, balance and coordination impairments, and, in some cases, cognitive and communication problems.

Patients with Parkinson's disease are at high risk of falling, particularly due to balance and postural instability. Consequently, fear of falling can lead to kinesiophobia (fear of movement), decreased engagement in activities of daily living, and difficulties in functional adaptation. Balance problems are among the primary motor deficits in Parkinson's disease and contribute significantly to gait disturbances, postural instability, and fall risk. Therefore, balance rehabilitation is a key focus in the management of Parkinson's disease, especially for fall prevention.

A detailed assessment of balance is essential for planning effective rehabilitation programs. According to the literature, balance evaluation in Parkinson's patients is generally performed using static and dynamic assessments. Commonly used tools include the Mini-BESTest, the Functional Reach Test, and the Timed Up and Go Test (TUG). However, a major contributor to balance problems is lower extremity muscle weakness, particularly in the ankle. While research shows a significant relationship between lower limb muscle weakness and increased fall risk in Parkinson's patients, existing assessment tools often lack direct quantitative measurements, which may reduce their clinical effectiveness.

The Enhanced Paper Grip Test (EPGT) can help address this gap. The EPGT provides a simple measurement of hallux plantar flexion strength without requiring specialized equipment. It can be used to assess fall risk in individuals with Parkinson's disease and has been suggested as a practical screening tool in geriatric populations. The validity and reliability of the test have also been demonstrated in individuals diagnosed with multiple sclerosis. The EPGT is easy to administer, requires minimal space, is low-cost, and quick to perform, making it a practical clinical tool. In this study, the researchers aimed to examine the validity and reliability of the modified paper grip test in Parkinson's patients.

Volunteer patients diagnosed with Parkinson's disease who applied to the SANKO University Sani Konukoğlu Application and Research Hospital Neurology Polyclinic will be included in the study. Patients who meet the inclusion criteria will be evaluated by Dr. Hakan Polat and Physiotherapist Fatma Yılmaz in the application laboratory of the Department of Physiotherapy and Rehabilitation, Faculty of Health Sciences, SANKO University. The role of Associate Professor Zekiye İpek Kırmacı in the study includes planning the study, formulating hypotheses, interpreting the results, and preparing the manuscript for publication.

The assessment form prepared by the researchers will be completed face-to-face with patients. First, demographic information and disease-related data (such as disease duration, affected side, and affected limb) will be recorded. Balance and gait will be assessed using the Mini-BESTest. The muscle strength of the ankle plantar and dorsiflexor muscles will be measured using a manual muscle testing device, and quality of life will be evaluated with the Parkinson's Disease Questionnaire-39 (PDQ-39).

Because fall risk in Parkinson's patients may be related to balance impairments, lower limb muscle weakness, particularly in the ankle, and reduced quality of life, these parameters will also be examined. Therefore, in this study, while evaluating the validity and reliability of the modified paper grip test in Parkinson's patients, its correlation with these parameters will also be investigated.

Before administering the tests, participants will receive a practical explanation of the procedures and will be allowed to rest prior to assessment. The order of testing will be as follows: first, the paper grip test performed by Dr. Hakan Polat, followed by the Mini-BESTest, assessment of ankle muscle strength, and evaluation of quality of life.