Pulley Injuries : The Science

From UkBouldering

Injury

Bollen SR, Gunson CK. (1990) Hand injuries in competition climbers. Br J Sports Med. 24(1):16-18. Copy on PubMed Cited by...

A retrospective study of 67 competitors at the British Open climbing competition, 1989. 26% had suffered a ring finger A2 rupture in the past. All had bowstringing when examined. 24% had a PIPJ fixed flexion deformity.

Klauser A, Frauscher F, Bodner G, Halpern EJ, Schocke MF, Springer P, Gabl M, Judmaier W, zur Nedden D. (2002) Finger pulley injuries in extreme rock climbers: depiction with dynamic US. Radiology 222(3):755-61. Abstract on PubMed Cited by...

Another retrospective. 64 climbers, 256 fingers assessed. Assessed the pulleys with ultrasound, looking at bone-tendon distance at levels of pulleys. 29% fingers symptomatic. 63% of these had MRI confirmed pulley injury. Of these 13% had partial A2 rupture, 14% full A2 rupture.

Schöffl V, Hochholzer T, Winkelmann HP, Strecker W Pulley Injuries in Rock Climbers Wilderness and Environmental Medicine 14(2):94–100 Abstract on PubMed Cited by...

604 injured climbers. All suspected pulley injuries had USS +/- MRI. Of 604...

Injury	N	Percent
Finger Injuries	247	41%
Forearm & Elbow	81	13.4%
Feet	55	9.1%
Hand	47	7.8%
Trunk	44	7.1%
Other	131	21.6%
Total	604	100

122 of 247 (49.3%) of finger injuries were pulleys. 50 of these pulley injuries (41%) were A2. Of these 34% were partial ruptures, 66% complete A2 ruptures. 87 pulley injuries followed up. 80 (92%) were grades I-III, of which 8% had persistent pain at 3 months following treatment with early functional therapy (not specified) and pulley protection in the form of a special ring. 6 of these (7.5%) still required taping at 1 year.

All grade IV injuries were treated without surgery (refused or misdiagnosed), and all required taping long term.

In summary, A2 injuries are the most common and occur mostly in the ring finger. Around 8% are grade IV injuries (more than one complete pulley rupture), and convention (but not necessarily evidence) suggests reconstruction in these cases. Grade IV injuries are more severe and bowstringing should be obvious clinically. Whether imaging (USS or MRI) is essential is debatable, plus in the UK access to these is limited.

Recovery

There are no studies on how rehab should be performed. Most papers looking at outcome go by the old-skool 4-6 weeks rest, then taping and slow introduction to climbing.

Strength measurement and clinical outcome after pulley ruptures in climbers. Schöffl VR, Einwag F, Strecker W, Schöffl I. Med Sci Sports Exerc. 2006 Apr;38(4):637-43. 21 climbers reviewed after pulley injury (mean of 3.46 years, 0.25 to 18 years range). Comparison of strengths of fingers performed after 2 days rest. 10 minutes specific warm up, then 10 minutes rest, then test. Assessed by pulling on 2cm, rounded edge and assessing drop in weight from body weight. Measured for individual fingers (index, middle, ring), then index/middle/ring together crimped and open. Comparison to uninjured side, plus other statistical analysis. Injury distribution:

Finger	Percentage
Ring	6.7%
Middle	25.9%
Index	3.7%
Little	3.7%

41% of injured fingers also noted to have restricted movement in PIPJ (5-10 degrees in most) Injured fingers showed same strength as uninjured fingers at 1 year.

Summary

No analysis done before 12 months, so unclear when full strength achieved. No standardised rehab program, thus unclear which approach best.

Taping

The effect of circumferential taping on flexor tendon pulley failure in rock climbers. Warme WJ, Brooks D. Am J Sports Med. 2000 Sep-Oct;28(5):674-8. 9 pairs of cadaveric hands aged 20-47yrs. Placed in a jig to recreate the crimp position. 2 fingers of each hand reinforced with tape (3 turns)- opposite fingers of each hand pair. FDS and FDP distracted to pulley failure point. A2 failed simultaneously with A3 and A4 in 55% of fingers. Statistical comparison of 22 pairs of fingers showed no improvement in strength with taping . Single pulley failure rates:

Pulley	Failure Rate
A1	1%
A2	27%
A3	2%
A4	15%
A5	0%

Biomechanical effectiveness of taping the A2 pulley in rock climbers. Schweizer A. J Hand Surg . 2000 Feb;25(1):102-7. In vivo study to assess bowstringing in fingers, along with the force of bowstringing in crimp grips. 16 fingers assessed using 2 types of taping. Taping over A2 reduced bowstringing by 2.8% and reduced force by 11% Taping over distal end pf proximal phalanx reduced bowstringing by 22% and absorbed 12% of force.

Impact of taping after finger flexor tendon pulley ruptures in rock climbers. Schoffl I, Einwag F, Strecker W, Hennig F, Schoffl V. J Appl Biomech. 2007 Feb;23(1):52-62. Assessment of H-taping and its ability to reduce the bone-tendon distance. USS assessment of 8 subjects with A2 rupture and multiple pulley ruptures of A2 and A3. Assessment of bone-tendon distance. H taping reduced bone-tendon distance by 16%, whereas circumferential taping did not reduce it. Strength improved by 13% in crimp position, none in open handing, using H taping.

GCW's Summary

Well, who knows. The cadaveric study has flaws- altered biomechanics from freezing, potential problems with testing methods etc: Fingers tested individually, with no thumb involvement- not true to most climbing grips. Frozen hands, thus tendon elasticity reduced possibly altering the results. Flexor chiasm function is complex and was not taken into account in this model, which may confound findings. The number of fractures (31.9%) raises concerns as to the nature and technique of loading of the fingers. Having said that the Strecker study appears to agree that there is no increase in strength with circumferential taping. Some may argue that this is observer bias from the inventor of the H technique. Basically, tape is cheap and likely does no harm if used for shorter (under 6 month) periods in rehab, I can’t see a problem with its use.

Other, non-SCIENCE stuff

Dave MacLeod : Pulley Injuries

Suggests use varied grip styles.
Variable approach to taping- states evidence shows no benefit whilst stating taping increases pulley strength by 12%.
Suggests rest of 1-3 weeks after pulley injury, until finger moves through normal range without pain.
After this, build up gradually but stop if you get pain, climbing open handed.
Ice the injured finger- this is well supported in other injury types.
No specific return to climbing protocol.

Dave MacLeod : Problems with Lay-off

Erik J Horst

Rest, ice, take NSAIDs (eg Ibuprofen) if swollen. Stop once swelling settles.
Light exercise when pain reduces.
Heated pad application 10 minutes, 3 times per day. Stop the fags, Jim.
Gradual return to climbing.
Return to full power climbing if not painful. Continue with taping for several months.

Other sites suggest similar regimes, equally vague.

GCW’s Recommendations

If you suspect you have sustained a pulley injury, stop climbing. If you are unsure of what you are doing, go and see somebody that has experience of treating these injuries. Rest the finger, apply ice for up to 10 minutes at a time to reduce swelling. NSAIDs have minimal evidence base, and have been shown to slow healing in other bony and tendon/ligament injuries. Personally, I avoid them but there’s no good SCIENCE to support me. There’s no good evidence that taping improves strength, but it’s cheap and easy so I personally would use it initially in the return-to-climbing phase. I’d try to reduce use and stop by 6 months. Return to climbing is the area with no evidence. I personally would suggest rest of 2-3 weeks, then reassess. During this initial period I’d do gentle movement exercises- finger flexion mostly, within limits of pain, plus gentle extension to (but not past) neutral. Once a full range of movement is painless, I would suggest beginning active rehabilitation whilst using taping. Now the lack of evidence kicks in and guessing starts. Open handing has been shown to reduce pulley stress, so a return to gentle climbing (openhanded style) would seem reasonbable. After another 3 weeks (studies have shown that collagen tissues need this time to adjust) you could move on (assuming there’s no pain) to the crimp grip. Full strength is regained at 12 months, although no studies have looked to see if this occurs earlier. In my experience, ligamentous/tendon recovery is complete by 6 months. Hence, I’d (tentatively) suggest a return to normal climbing by then (if painfree).