Notta's Node

Historical Overview

• A Notta’s node is a palpable, localized, expansion (enlargement0 of a flexor tendon, just at or distal to the A-1 pulley, indicating a likely “trigger digit.”¹
• Notta first described these nodules and trigger digits (stenosing tenosynovitis) in 1850.¹

Description

• Finding a tender palpable nodule just proximal to the A-1 pulley is suggestive of a trigger digit.²

Pathophysiology

• Stenosing tenosynovitis is a pathologic disproportion between the volume of the retinacular sheath and its contents, owing to inflammation and hypertrophy of the former.³ This imbalance inhibits gliding of the flexor tendon through the A-1 pulley.⁴
• Notta’s nodes then form as normal tendon architecture is disrupted by the constriction of the inflamed sheath.⁵

Instructions

1. Take a patient history
2. Palpate the flexor tendon of the symptomatic digit just distal to the A-1 pulley

Related Signs and Tests

• Tenderness of Notta’s node
• A-1 pulley tenderness
• Triggering/locking/catching of the proximal interphalangeal joint of the affected digit or the interphalangeal joint of the thumb.

Diagnostic Performance Characteristics

• The classic presentation of popping and locking of a trigger finger is typically all that is needed for a diagnosis of trigger finger; however, with acute onset of symptoms, patients may present with pain and swelling over the involved flexor sheath with avoidance of finger motion. In these cases, the classic popping and triggering are not seen, and the diagnosis of trigger finger must be differentiated from infection or some other traumatic injury.⁴

• A positive result occurs when there is a palpable sometimes visible nodule in the thumb flexor tendon (FPL).

• A negative result occurs when there is no palpable change in the thumb flexor tendon.

• There are many classification systems for trigger finger, but none is commonly accepted.²
• If desired, the diagnosis may be confirmed with an injection of lidocaine into the flexor sheath, which should relieve the pain associated with the triggering and allow the digit to become actively or passively extended.
• There is no role for imaging in diagnosis; x-rays are considered unnecessary in patients without history of inflammatory disease or trauma.⁴ Although usually unnecessary ultrasound can be confirmatory.
• Notta’s nodes are most frequently seen in children.

1. Ryzewicz M, Wolf J. Trigger digits: principles, management, and complications. J Hand Surg Am 2006;21(1):135-46. PMID: 16443118
2. Hammert  W, et al. ASSH Manual of Hand Surgery. Philadelphia: Lippincott Williams and Wilkins, 2010.
3. Makkouk A, et al. Trigger finger: etiology, evaluation, and treatment. Curr Rev Musculoskelet Med 2008;1(2):92-6. PMID: 19468879
4. Saldana M. Trigger Digits: Diagnosis and Treatment. J Am Acad Orthop Surg 2001;9:246-52. PMID: 11476534
5. Hueston JT, Wilson WF. The aetiology of trigger finger explained on the basis of intratendinous architecture. Hand 1972;4(3):257–60. PMID: 5083965