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Trigger finger release with hand surface landmark ratios: an anatomic and clinical study
B J Wilhelmi1, N Snyder, J E Verbesey
1Division of Plastic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, USA. bwilhelmi@siumed.edu
Plastic and Reconstructive Surgery
|September 8, 2001
Summary
Surface landmark ratios accurately predict the A1 pulley
Area of Science:
- Anatomy
- Orthopedics
- Minimally Invasive Surgery
Background:
- The A1 pulley is crucial for finger flexion, and its precise anatomical location is vital for effective surgical release, particularly in minimally invasive techniques.
- Existing anatomical descriptions of the A1, C0, and A2 pulleys vary, leading to potential confusion during surgical procedures.
- Accurate identification of pulley margins is essential for safe and complete release, minimizing complications in trigger finger treatment.
Purpose of the Study:
- To establish reliable surface landmark ratios for locating the proximal and distal margins of the A1 pulley.
- To clarify anatomical discrepancies regarding the A1, C0, and A2 pulleys.
- To validate the clinical utility of these ratios in minimally invasive A1 pulley release for trigger finger.
Main Methods:
- Dissection of 256 fingers from 64 cadaver hands to measure A1 pulley dimensions and their relation to surface landmarks.
- Correlation of the distance between the palmar digital crease and proximal interphalangeal crease with the proximal A1 pulley edge location.
- Assessment of A1 pulley length variations across different fingers and identification of the C0 pulley's position.
Main Results:
- The distance from the palmar digital crease to the proximal interphalangeal crease (2.42 cm) closely approximates the distance to the proximal A1 pulley edge (2.45 cm).
- A1 pulley length varied significantly, being shorter in the small finger (0.98 cm) compared to other fingers (1.17 cm).
- A cruciate (C0) pulley was consistently identified 0.46 cm proximal to the palmar digital crease, serving as a landmark.
Conclusions:
- Surface landmark ratios provide an accurate method for locating the proximal A1 pulley edge, aiding trigger finger release.
- The study clarifies the anatomy of the pulley system, confirming the presence and location of the C0 pulley.
- These findings facilitate complete trigger finger release using open or minimally invasive techniques by providing reliable anatomical guidance.
