Extrinsic Tightness Test | Hand Surgery Resource

Exams and Signs

Historical Overview

Extrinsic extensor tendon tightness may arise from rheumatoid arthritis (RA).
J. William Littler, one of the founders of hand surgery, first introduced the Littler release, as a procedure to alleviate the destruction of joints in RA.¹

Description

Extrinsic tightness is caused by dysfunction in extrinsic tendons and muscles.
Extensor and flexor muscles can be affected by extrinsic tightness.²
If the extensor tendons become adherent over the dorsum of the hand or wrist, finger flexion becomes limited.³

Pathophysiology

Extrinsic tightness may cause metacarpophalangeal (MP) joint instability, which leads to classic finger deformities in RA.¹
Both extrinsic and intrinsic tightness may follow a crush injury, with or without metacarpal fracture, after extensor lacerations that scar the dorsal structures of the hand or wrist. This will limit the excursion of the tendons and restrict combined MP and proximal interphalangeal (PIP) joint flexion.⁴

Instructions

Passively extend the MP joint while flexing the PIP joint.³ Observe whether the PIP joint can be flexed as usual.
Passively flex the MP joint while flexing the PIP joint and observe whether the PIP joint can be flexed as usual. When the patient has extrinsic tightness, the PIP joints will flex as usual with the MP joints extended, but they will have restricted flexion when the MP joints are flexed.
Compare this outcome with the results of the patient’s contralateral hand.

Related Signs and Tests

Definition of Positive Result

A positive result occurs when the PIP joint can be flexed while the MP joint is extended, but not when the MP joint is flexed.

Definition of Negative Result

A negative result occurs when the PIP joint cannot be flexed while the MP joint is extended.

Comments and Pearls

In ideal extensor physiology, there is a delicate balance between the extrinsic and intrinsic systems. If there is a dysfunction in the extrinsic tendon system, a functioning intrinsic system may compensate.⁵
To treat extrinsic tightness, hand therapy should be used for at least 6 months before surgical options are considered. Surgical options include tenolysis and extrinsic extensor release.⁴ In some cases, a Littler release may be appropriate in RA.
In the early stages of MP involvement in RA, synovectomy may help relieve symptoms.⁶
In current practice, extrinsic extensor tightness is rare. However, it can be seen when extensor tendon repairs scar the dorsal hand or wrist and limit tendon excursion.

Diagnoses Associated with Exams and Signs

References

Littler JW. Surgical Clinics of North America. Vol 47. New York, 1967
Rayan G, Akelman E. The Hand: Anatomy, Examination, and Diagnosis. Philadelphia: Lippincott Williams & Wilkins, 2012.
American Society for Surgery of the Hand. The Hand: Examination and Diagnosis. American Society for Surgery of the Hand, 1983.
Wolfe S, ed. Green’s Operative Hand Surgery. Philadelphia: Elsevier, 2011.
Hanz KR, Saint-Cyr M, Semmler MJ, et al. Extensor tendon injuries: acute management and secondary reconstruction. Plast Reconstr Surg 2008;121(3):109e-120e. PMID: 18317093
Chung KC, ed. Hand Surgery Update V. American Society for Surgery of the Hand, 2011.