Make an O
Thumb–index circular pinch shape (O formation)
Goal
Practices controlled opposition geometry used in writing and tool handling.
Motion taxonomy (reference)
Also called: c to o transition · o position · thumb index circle
Muscles — adductor pollicis, first dorsal interosseous, opponens pollicis, thenar muscles
Tendons — thumb flexor and opposition tendons, thumb opposition tendons
Bones / joints — index DIP/PIP, metacarpals, thumb CMC, thumb CMC joint, thumb MCP, thumb MCP joint
Indexed benefits: helps thumb-index coordination · improves pinch base control · improves pinch precision · strengthens thumb stability · supports tip control · trains opposition
Common contexts: CMC stability · fine motor tasks · pinch control · thumb opposition · thumb rehab · tip pinch rehab
Best for
- Fine motor shaping
- Preparation for circular tool handles
Default dose
10 reps • 3×/day
Setup
- Seated; forearm supported.
Steps
- 1Touch thumb pad to side of index finger to form a circle.
- 2Hold 2 seconds.
- 3Release and reshape the O.
Cues
- Round shape, not a squeeze.
- Soft jaw.
Common mistakes
- Crushing into pain for a 'perfect' circle.
Stop if you feel
Stop rules
- Sharp pain (≥ 4/10)
- Increasing swelling during or after
- New or worsening numbness or tingling
- Color change in fingers (pale, blue, red)
- Wound opens, drains, or feels hot
- Next morning is worse than the day before
Progressions
- Trace a small coin inside the O without dropping.
Regressions
- Larger O with less flexion.
Used in
What to do next — not a dead end
Suggestions use body region, goal, motion type, and allowed phases — not your medical record. After surgery or a flare, follow your clinician first.
~2–5 min as a focused practice block
10 reps · 3×/day
None required — table or bodyweight only.
Phases 2, 3, 4
Generally lower load — still respect pain and swelling.
Next best movements
Later phase or richer progression when you are ready.
Prerequisite / gentler lane
Same region and intent — usually earlier phase or lower risk.
Commonly paired with
Different primary goal, same region — typical mixed sessions.
Related movements
Similar mechanics, goals, or anatomy.
Keep momentum without overdoing it
Log a short check-in to protect your streak — even one quality set counts.