The assisted thumb bend uses your other hand to move a stiff thumb across the palm toward the little finger side, then back out again. You sit with your forearm resting on a table, palm up, hold the thumb with your other hand and guide it through the bend while the thumb itself stays relaxed. The app title calls it passive thumb flexion. Physios often give it for a thumb that has gone stiff after an injury, an operation or weeks in a cast, before the thumb can bend far by itself.

How to do the assisted thumb bend

Sit at a table and rest the forearm of the stiff thumb on it, palm facing up and the fingers relaxed, as in the video.
Reach across with your other hand and hold the stiff thumb securely between your thumb and index finger. Let the stiff thumb go loose, so the helping hand does the moving.
Guide the thumb slowly across the palm toward the base of your little finger, only as far as a gentle stretch.
Take it back the same way to where it started.
Repeat slowly, keeping the wrist, the forearm and the rest of the hand still on the table.

What you should feel

A gentle stretch across the back of the thumb and around its joints as it bends. It may feel stiff, but it should not be sharply painful.

Common mistakes

Forcing the thumb past the point of a comfortable stretch.
Tensing the stiff thumb so it fights the helping hand.
Curling the fingers or bending the wrist along with the thumb.
Bouncing or jerking the thumb instead of moving it slowly.

How often

Many programs use about 10 slow bends, 2 or 3 times a day, sometimes holding the gentle stretch for a few seconds at the end. Your physio will adjust this.

Stop and check with your physio if

Sharp pain in any joint of the thumb, or at the base of the thumb near the wrist.
The thumb catches, clicks painfully or gets stuck as it bends.
Your thumb or fingers start to tingle or go numb during the stretch. If it stays after you stop, or keeps getting worse, get medical advice the same day. If one side of your face or body suddenly goes numb or weak, or your speech becomes slurred or muddled, call emergency services, even if it goes away.
Swelling around the thumb that is worse after the session or the next day.
Suddenly being unable to straighten the end of your thumb or lift it back, especially in the weeks after a wrist fracture. A thumb tendon can snap, so have a doctor check it within a few days.
Since the fracture or cast, the hand is getting more painful rather than less, the skin becomes very sensitive to light touch, or the hand changes color, temperature, swelling or sweating compared with the other one, or looks shiny. See your doctor or physio as soon as you can, within a few days at most, as this can be complex regional pain syndrome (CRPS) and early treatment may help.

From the clinic

The helping hand does the work here, so the muscles listed are the ones along the back of the thumb that get stretched as it bends. The voice guide says to hold the thumb firmly, which means a secure hold, not a hard push. Stop each bend at a gentle stretch. The range comes back over days and weeks, not in one session. Once the thumb bends well by itself, thumb flexion is the same movement without help.

After a broken wrist, hand or forearm, or surgery on any of them such as a tendon repair, start only when your doctor, surgeon, physio or hand therapist says the bone or repair is ready for this, and follow their plan for how much to do. After any tendon repair in the thumb, how far and how hard the thumb may be moved follows a strict timetable, so use this only in the way your surgeon or hand therapist has shown you.

Clicking or sticking as the thumb bends may point to trigger thumb, so let your physio know before you carry on. Bending the thumb across the palm also stretches the tendons on the thumb side of the wrist, so if that area is sore, as in de Quervain's tenosynovitis, ask your physio how far to go before you start. Do the same if you have arthritis at the base of the thumb (hand osteoarthritis). That joint often stiffens with the thumb drawn in toward the palm, and many programs stretch the thumb out to the side instead. With rheumatoid arthritis in the hand, go lighter on the stretch and check with your physio how much to do during a flare.

Written and checked by the PocketPhysio editorial team. Last updated 2026-09-28.

This page is general education, not a diagnosis or a personal treatment plan. If you have pain, an injury or a health condition, see a physiotherapist or doctor before starting new exercises.

Assisted thumb bend