Forearm rolling test

The forearm rolling test is one of the subtle signs of hemiparesis.(1) The patient holds the forearms horizontally with the fists and distal forearms overlapping, then rotates the fists around each other, first in one direction and then the other (Video 1) Normally, the fists and forearms roll about each other symmetrically with an equal excursion on both sides. With a unilateral corticospinal tract lesion, the involved moves less than the normal side, rotating in a tighter arc. The patient appears to plant, fix or “post” one forearm and to rotate the opposite forearm around it. Like pronator drift, patients may have abnormal forearm rolling in the absence of any weakness on formal testing. In Video 1, a patient with a mild left hemiparesis shows a decreased excursion of the involved side on the forearm rolling test.

Finger rolling is a variant in which the patient rotates just the index fingers.(2) It is even more sensitive than the forearm rolling test. In Video 2, a patient with MS has normal forearm rolling but posting of the left index finger with finger rolling. There was no weakness on formal strength testing. In the thumb rolling test, the patient rotates only the thumbs.(3)

Forearm rolling has a sensitivity of 17-87%, specificity of 97-98%, positive LR of 15.6 and negative LR of 0.6 in the detection of contralateral hemispheric disease.(4) Index finger rolling has a sensitivity of 33-42%, a specificity of 92-98%, positive LR of 6.0 and negative LR of 0.7 in the detection of contralateral hemispheric disease.(4) In a series of patients with mild hemiparesis, thumb rolling was more sensitive (88%) than pronator drift (47%), forearm rolling (65%) or index finger rolling (65%). Patients with bradykinesia or rigidity from extrapyramidal disease may also show decreased excursion of the affected limbs.

Some of the other subtle signs of hemiparesis include pronator drift and other pronator signs, the digiti quinti sign, loss of fine motor control and decreased dexterity (e.g., finger tapping, foot tapping), leg drift and decreased arm swing on walking.(5,6)

References

1. Sawyer, RN, Jr., Hanna, JP, Ruff, RL, et al. Asymmetry of forearm rolling as a sign of unilateral cerebral dysfunction. Neurology. 1993; 43:1596-1598.

2. Anderson NE. The forearm and finger rolling tests. Pract Neurol. 2010;10:39-42.

3. Nowak, DA. The thumb rolling test: a novel variant of the forearm rolling test. Can J Neurol Sci. 2011; 38:129-132.

4. McGee, S. Evidence based physical diagnosis. 3 ed. Philadelphia: Elsevier/Saunders, 2012.

5. Campbell WW. DeJong's the neurologic examination, 7th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins, 2013.

6. Campbell WW. Clinical signs in neurology: a compendium. Philadelphia: Wolters Kluwer Health, 2016.