The A2 and A4 pulleys are biomechanically critical — loss of either produces measurable bowstringing and reduced digital flexion power. The A2 pulley is the most important: its loss reduces digital flexion strength by 10-15% and causes visible bowstringing. In rock climbing, forceful crimping loads the A2 pulley to near-failure — partial A2 tears are the most common climbing injury.
Maintain the flexor tendons against the bone during digital flexion; without them the tendons bowstring across the palm producing inefficient force transmission and reduced grip strength
A2 pulley rupture produces a palpable cord along the finger during flexion (bowstringing) and increased tendon-to-bone distance on ultrasound. Isolated A2 tears are managed conservatively with ring splinting to reduce bowstringing. Multiple pulley ruptures requiring reconstruction use palmaris longus or extensor retinaculum grafts looped around the phalanx in the Bunnell-Williams technique.
Crimp-loading failure of the A2 annular pulley producing finger bowstringing managed with ring splinting for single pulley and reconstruction for multiple pulley injuries.
This website uses cookies to enhance your experience. Some are essential for site functionality, while others help us analyze and improve your usage experience. Please review your options and make your choice.
If you are under 16 years old, please ensure that you have received consent from your parent or guardian for any non-essential cookies.
Your privacy is important to us. You can adjust your cookie settings at any time. For more information about how we use data, please read our privacy policy. You may change your preferences at any time by clicking on the settings button below.
Note that if you choose to disable some types of cookies, it may impact your experience of the site and the services we are able to offer.
Some required resources have been blocked, which can affect third-party services and may cause the site to not function properly.
This website uses cookies to enhance your browsing experience and ensure the site functions properly. By continuing to use this site, you acknowledge and accept our use of cookies.
