Anatomy
The flexor tendons of the fingers are held to the finger bones (phalanx) by 5 strong ligaments (flexor pulleys) A1-A5. It is often pulleys A2, A3 and A4 that rupture.
(Idrætsskader, 2. udgave, FADL’s forlag)
Cause of the problem
When the flexor tendons of the fingers are severely strained, the ligaments (flexor pulleys) can rupture, causing the flexor tendon to press upwards like a bowstring (see figure), causing pain. It is a common injury in climbers and is called ‘climbing finger’.
The A2 pulley breaks most frequently, especially on the ring finger. Bowstringing requires the rupture of both A2 and A3 pulleys.
When climbing and holding on with your fingertips, you can hold your hand in two ways. You can either maximally bend the outer joint (DIP joint) while the middle joint (PIP) and knuckles (MCP) are (almost) stretched (‘Open-Hand Grip’), or you can bend 90 degrees in the middle joint (PIP joint) while the outer joint is overstretched and the knuckles are (almost) stretched (‘Crimp Grip’). The Crimp Grip technique increases the load on the A2 pulley more than 30 times compared to the Open-Hand Grip ( Vigouroux, L. et. al., 2006 ). In general, the greater the force on the fingertips when climbing, the greater the load on the A2 pulleys.
Symptoms
Many people hear a pop in the finger if the pulley breaks. There is pain when trying to bend the finger against resistance and when pressing on the injured pulley. There is often swelling along the flexor tendon.
Examination
Many people hear a pop in the finger if the pulley breaks. There is pain when trying to bend the finger against resistance and when pressing on the injured pulley. There is often swelling along the flexor tendon.
MRI and ultrasound scans can often distinguish between partial rupture (strain) or total rupture. When A2 and A3 pulleys rupture, dynamic ultrasound scans show bowstringing, where the flexor tendon is lifted and does not make contact with the finger bone when the flexor tendon is activated.
Treatment
Reduction of pain-triggering activity. You can try to stabilise and relieve the flexor tendon by taping the pulley around the finger so that the tape holds the flexor tendon (partially) in place (Larsson R, et al. 2022). Most pulley ruptures can be treated conservatively. If multiple pulleys are ruptured or if discomfort does not resolve with load reduction and careful rehabilitation within the pain threshold, surgery to attempt to restore the pulleys is an option (Miro PH, et al. 2021).
Injuries are categorised into 4 levels of severity (Grade 1-4), which have implications for treatment and rehabilitation:
|
|
Grade 1 |
Grade 2 |
Grade 3 |
Grade 4 |
|
Pulley damage |
Partial rupture (sprain) |
Complete A4 breaking. Or partial A2 or A3 breaking |
Complete A2 or A3 breakage |
Multiple ruptures (A2-A3 or A2-A3-A4) |
|
Treatment |
Rehabilitation |
Rehabilitation |
Rehabilitation |
Possible surgery |
|
Immobilisation |
None |
Approx. 10 days |
Approx. 10-14 days |
2 weeks after any surgery |
|
Strength training |
After 2-4 weeks |
After 2-4 weeks |
After 4 weeks |
After 4 weeks |
|
Pulley protection |
H-Tape for 3 months after climbing has started |
A2-Tape, A3-Tape (H-Tape) for 3 months after climbing has started |
A2-Tape, A3-Tape (H-Tape), (possibly Pulley ring) for 6 months after climbing has started |
Pulley ring for more than 1 year after climbing has started |
|
Easy climbing exercises |
After 4 weeks |
After 4 weeks |
After 6-8 weeks |
After 4 months |
|
Full climbing exercises |
After 6 weeks |
After 6-8 weeks |
After 3 months |
After 6 months |
Adapted from Schöffl & Schöffl, 2006
Rehabilitation
Conditioning training in the form of running and rehabilitation according to the guidelines under rehabilitation, in general, can continue unchanged. It is appropriate to maintain mobility by gently exercising the hand muscles within the pain threshold.
Bandage
You can stabilise and relieve the flexor tendon by taping the circular band around the finger so that the tape holds the flexor tendon (partially) in place (H-tape).
