Hand Surgery Source

Pinch Strength

Test, Exam and Signs

Historical Overview

Orthopedists check the strength of the hand by testing how effectively the patient is able to utilize lateral (key) pinch and pulp pinch. 

Description

The pinch strength test evaluates the intrinsic and extrinsic hand muscles and shows how much power the patient demonstrates in these muscles. Observing a patient’s ability to pinch and measuring this ability with a pinch meter will indicate whether the patient has symptoms of illness such as arthritis, carpal tunnel syndrome and cubital tunnel syndrome.

Pathophysiology

Poor pinch strength arises from a weakness in the intrinsic and extrinsic hand muscles.

Instructions

  1. Ask the patient to demonstrate lateral (key) pinch and pulp pinch with the affected hand.
  2. Observe if the patient is able to perform these kinds of pinches with the affected hand.
  3. Use a pinch meter to measure the strength of the pinches.
  4. Try the other hand for a comparison.

Variations

  • Ask the patient to grip repeatedly at an increased speed. Check if there is a decrease in force, compared with static testing.

Related Signs and Tests

  • Froment’s sign
Presentation Photos and Related Diagrams
  • Key Pinch being measured by pinch meter.
    Key Pinch being measured by pinch meter.
  • Pulp to Pulp (Tip Pinch) being measured by pinch meter.
    Pulp to Pulp (Tip Pinch) being measured by pinch meter.
Definition of Positive Result
  • A positive result occurs when the patient exhibits poor pinch strength.
Definition of Negative Result
  • A negative result occurs when the patient exhibits healthy pinch strength.
Comments and Pearls
  • Most patients are about 20% stronger in one hand than in the other.
Diagnoses Associated with Tests, Exams and Signs
References
  1. Culp R, Jacoby S.  Musculoskeletal Examination of the Elbow, Wrist and Hand: Making the Complex Simple. New Jersey: SLACK Incorporated, 2012.
  2. Kozin S, Porter S, Clark P, et al. The Contribution of the Intrinsic Muscles to Grip and Pinch Strength.  J Hand Surg Am 1999;24:64-72. PMID: 10048518