Understanding the Thumb CMC Grind Test Assessment
To assess for **Osteoarthritis (OA)** in the **Carpometacarpal (CMC) joint** of the thumb (Base of the thumb).
Watch How It's Done
How do I start?
Patient is sitting. Forearm is supported.
What happens?
The examiner grasps the patient's thumb metacarpal and applies an **axial compression load** (pushing down the length of the thumb) and simultaneously **rotates and moves** the metacarpal in a circular grinding motion over the trapezium.
In Plain English
What Does a Positive Result Mean?
The reproduction of the patient's **pain** and/or a palpable **crepitus (grinding/crunching sound)**, suggesting degenerative changes in the joint cartilage.
Helpful Tip:
This is a key diagnostic test for thumb basal joint arthritis.
Safety First
This guide is to help you understand what happens in a clinic. Do not try to diagnose yourself. If you have severe pain, swelling, or cannot put weight on your leg, please visit an urgent care center or your doctor immediately.
Other Wrist/Hand Tests
Beighton Score
To quantify **generalized joint hypermobility** (laxity) across the body. The wrist/hand components assess passive joint laxity.
Bunnell-Littler Test (or Finochietto-Bunnell Test)
To differentiate between **Intrinsic Muscle tightness** (interossei and lumbricals) and **Capsular restriction** at the proximal interphalangeal (PIP) joint.
De Quervain's Tenosynovitis
This is the **condition name** (inflammation of the APL and EPB tendons), not a specific test. The Finkelstein Test is the primary diagnostic test.
Elson Test
To assess the integrity of the **Central Slip** of the Extensor Digitorum Communis (EDC) tendon, rupture of which leads to a Boutonniere deformity.