Research > Technology Reviews > Using a “pulley protection brace” to support your finger

Pulley Protection Braces: A Review of the Swiss and American Products

I’m going to summarize very briefly the most practical information I’ve found regarding a device called a “pulley protection brace.”  For more in-depth information into this and other injury-related information, I encourage you to visit the injury section of the Beta Angel Research Inventory. Note: see the end for some practical prevention advice.

A slightly ridiculous oversimplification to get you caught up

Pulley’s are little tendons which wrap around each of your finger bones at 5 different locations.  Their purpose is to keep the tendon which flexes (long flexor tendon) your finger from “bowstringing” or separating from the bone.  Unfortunately, as your flexor tendon shortens, it has a habit of creating something like a “sawing” motion against your pulleys, which has the potential to create little micro-tears.  Due to the biomechanics of your finger while crimping, these tears primarily occur in the A2 and A4 pulley. 

Why is bowstringing an indication that something is wrong?

Researchers measure bone-to-tendon distance and use it as an indicator that something is wrong because more bowstringing leads to a reduced ability to flex the finger.

The “pulley ring” – The Swiss research

3-D Printing Template for Andi’s Brace

Dr. Andreas Schweizer is considered to be one of the top pulley specialists in the world.  He developed a “pulley ring” which helps keep bowstringing to a minimum by compressing the tendon toward the bone.  This effect takes strain off the pulley while scar tissue forms.  Dr. Schweizer’s 2016 study on 47 climbers with single pulley ruptures had very positive results both for the bone-to-tendon distance and return to previous climbing grade.[1]

View from the insider of the finger with the pulley brace on the outside

By placing the pulley ring at the edge of the pulley but before the appropriate joint, bowstringing was reduced by 50% and 40% in the A2 and A4 pulleys respectively. [2]   The pulley ring has openings on either side in order to avoid compressing “neuro-vascular bundles”, which are needed for circulation.  Because he’s a doctor, Andi’s brace is for rehabilitation, not prevention.  However, an American version exists of a different flavor.   

The SPOrt™ – The American Approach

Dr. Winston Warme is in the Department of Orthopaedics and Sports Medicine at the University of Washington.  Assuming no pain, the maker of the SPOrt™ suggests it can be used while climbing and even training.  The device is structured differently from Dr. Schweizer’s, in that the opening is placed on the back of the finger, rather than the side.  Additionally, it appears to be worn slightly back (toward the knuckles), in comparison.  Finally, Dr. Warme appears to recommend his only for the A2 pulley.  Due to the distinctions between the two braces, it’s challenging to make effectiveness comparisons.  However, Dr. Warme has a research paper involving 20 rock climbers currently undergoing peer review.  You can find the SPOrt™ at Dr. Warme’s website: ROCKNSPORT.

When should you use a pulley protection brace?

The research trial was used on climbers with a single A2 or A4 pulley rupture.  Additionally, a conference paper at the 2018 Chamonix Research conference highlights good initial results from treating multiple pulley ruptures with two pulley protection braces.[3] Dr. Warme’s website recommends his brace can be used for soreness at the base of the finger on the palm side, complete A2 pulley ruptures, partial A2 pulley injuries (chronic or acute), and returning to climbing after an A2 reconstruction surgery.  Both Dr. Schweizer and Dr. Warme recommend working with a physical therapist.  Dr. Schweizer has a series of recommendations involving the brace, tape, and movement exercises. You can download his recommendations below:

Practical advice for practical people

If you’re in the United States and already injured, you can go to Dr. Warme’s website and purchase your “kit.”  However, since he markets his device only for the A2, you may need to contact him directly about whether it can be sufficiently modified for the A4.  With the 3D Model and Dr. Schweizer’s treatment plan, which he sent me, it’s possible for Physical Therapists in the United States who are familiar with working with thermoplastic material to construct them and follow a directed plan. If you’re a PT, feel free to contact me for that guidance.

If you’re not injured, here’s some prevention advice: one of Dr. Schweizer’s research studies found that it takes 100-120 progressively difficult moves to properly warm-up the pulleys.[4][5]  How did they define “proper?” By looking at the relationship between grabbing holds and the distance to the bone of your long flexor tendon using a device that measures physical pressure and converts it into an electrical signal.  Andi recommends 3-4 routes with 40 moves or 8-12 boulder problems of progressive difficulty.[6]

Graphic from one of Dr. Schweizer’s research papers: “Sport Climbing from a Medical Point of View,” Published in Swiss Medical Weekly (2012), 142:w13688.

[1] M. Schneeberger, A. Schweizer, “Pulley Ruptures in Rock Climbers: Outcome of Conservative Treatment With the Pulley Protection Splint – A Series of 47 Cases,” Wilderness Environmental Medicine, June 2016, Vol. 27:2, 211-218

[2] A. Schweizer, “Sport Climbing from a Medical Point of View,” Published in Swiss Medical Weekly (2012), 142:w13688

[3] A. Schweizer, “Conservative Treatment of Triple Finger Flexor Pulley Disruption,” Conference Paper from the International Rock Climbing Research Association’s 2018 conference in Chamonix, France.

[4] A. Schweizer, “Treatment of Flexor Pulley Injury in Rock Climbers”

[5] Schweizer A. Biomechanical properties of the crimp grip position in

rock climbers. J Biomech. 2001;34:217–23.

[6] Ibid “Treatment”