1. Potential for overuse/overloading injuries
↑ stress onto loadbearing joints
↑ stress caused by weight-bearing motion
introduces ↑ risk
Shoulder-dependent population ↑ risk
Sledge hockey
high velocity
high impact
minute contact area transfers energy
Limited research majority gameplay
Similar motion to cross-country skiing
Poling sport information
Similar analytical parameters to gold standard
hip gait
Running
Jumping
Asymmetry
∴ parallel interpretations & predications can
be made regarding potential injuries
Investigation of the relationship between peak impact and push-off reaction forces, and
potential upper-limb overuse/overloading injuries introduced from skating in the sport of
sledge hockey
Gal A.M. 1, Chan A.D.C. 1 & Hay D.C. 2
1
2
1. INTRODUCTION
SKATING
3. RESULTS
Identify peak pick-plant and push-off reaction forces to
predict overuse/overloading injuries potentially caused
from skating in sledge hockey
OBJECTIVE
Swing Phase
Contact Phase
2. METHODOLOGY
REFERENCES & ACKNOWLEDGMENT
Acknowledgements Dr. M. Lamontagne & Dr. D. Benoit (Human Movement
Biomechanics Laboratory U Ottawa) & M. Haefele (Research Assistant)
[1] G. Bergmann, “Hip 98: loading of the hip joint.” Biomechanics Lab., Free University of Berlin, 2001.
[2] A. Hreljac, R. N. Marshall, and P. A. Hume, “Evaluation of lower extremity overuse injury potential in runners:,” Med. Sci.
Sports Exerc., pp. 1635–1641, Sep. 2000.
[3] R. Arvin Zifchock, I. Davis, J. Higginson, S. McCaw, and T. Royer, “Side to side differences in overuse running injury
susceptibility: A retrospective study,” Hum. Mov. Sci., vol. 27, pp. 888–902, 2008.
[4] M. S. Ferrara and C. L. Peterson, “Injuries to athletes with disabilities,” Sports Med., vol. 30, no. 2, pp. 137–143, 2000.
[5] M. S. Ferrara and R. W. Davis, “Injuries to elite wheelchair athletes,” Int. Med. Soc. Paraplegia, vol. 28, pp. 335–341,
1990.
[6] C. H. Yeow, P. V. S. Lee, and J. C. H. Goh, “Sagittal knee joint kinematics and energetics in response to different landing
heights and techniques,” The Knee, vol. 17, no. 2, pp. 127–131, Mar. 2010.
[7] J. Hawkeswood, H. Finlayson, R. O’Connor, and H. Anton, “A pilot survey on injury and safety concerns in international
sledge hockey,” Int. J. Sports Phys. Ther., vol. 6, no. 3, p. 173, 2011.
[8] M. S. Kocher, J. A. Feagin, and others, “Shoulder injuries during alpine skiing,” Am. J. Sports Med., vol. 24, no. 5, pp. 665–
669, 1996.
[9] Vicon Motion Systems Ltd., Nexus. U.K.: Vicon Motion Systems Ltd.
[10] BTS Bioengineering, “BTS Wireless sEMG,” BTS Bioengineering, 2016. [Online]. Available:
http://www.btsbioengineering.com/.
[11] Bertec Corp., “Bertec Force Plate,” Bertec, 2016. [Online]. Available: http://bertec.com/products/force-plates/.
[12] Kistler Instrument Corp., “Kistler Force Plate,” Kistler: measure. analyze. innovate., 2016. [Online]. Available:
https://www.kistler.com/ca/en/.
[13] J. R. Potvin and S. H. . Brown, “Less is more: high pass filtering, to remove up to 99% of the surface EMG signal power,
improves EMG-based biceps brachii muscle force estimates,” J. Electromyogr. Kinesiol., vol. 14, no. 3, pp. 389–399, Jun.
2004.
[14] MathWorks, MATLAB. The Mathworks Inc., 1994.
Figure 1 (↑). Off-ice study-specific modified on-ice sledge. Modifications
include: A) two youth size rollerblade chassis, each with two 65 mm wheels
(ABEC 5) in the front and backmost positions, B) front support wheel, and C)
telescopic leg-rest design allowing for 2” increment adjustments to a max of
15”.
Figure 4 (←). SC sagittal plane start
position. Post “Go”, participant
initiated initial contact phase was
acquired as they propelled
themselves and sledge through the
remaining MOCAP system (max 2
strokes to a coasting stop).
Figure 5 (→). MC sagittal plane start
position. Post “Go”, participant
initiated 2nd or 3rd contact phase was
acquired as they propelled
themselves and sledge through the
remaining MOCAP system (max 4
strokes to a coasting stop).
A
B C
Figure 3 (↑). MOCAP software regenerated propulsion
phase in sledge hockey. Left – initial pick-plant. Right –
final pick-off.
5 right-handed adult male able-bodied athletes
Sledge hockey & poling sport naïve
Asymmetrical bilateral skating predicted
(< optimal)
Study-specific design acquired left, right & sledge-body
ground reaction forces (2000 Hz)
3 useable trials / effort test (good force plate contact)
for both start cycle (SC) and mid-cycle strokes (MC)
Submaximal efforts (Sub Max)
Maximal efforts (Max)
2 participants performed one additional MC maximal
effort test (coin-flip variation)
Data were processed offline using MATLAB
Low pass zero-lag 2nd order Butterworth filter (12
Hz) applied against motion capture (MOCAP) raw
signals (250 Hz)
RecoveryPreparation Propulsion
Figure 2 ( ← ). Study-specific 4 force plate design
centrally located within a 10 camera MOCAP system.
Participants were equipped with 5 bilateral upper
torso/limb surface electromyography (sEMG)
electrodes. sEMG were not analyzed in this study.
Peak Resultant Force 1.2 – 3.1 x
body weight per arm
Pick-Plant Force >> Push-Off Force
↑ Reaction Forces → ↑ Torque
Mid-Cycle Force >> Start Cycle Force
>>
>>
Max Effort Force >> Sub Max Effort
Force
>>
4. Discussion / Conclusion
Injury is more likely to be caused by:
Pick-Plant
Continuous Motion
Maximal Effort
Compressive Forces
↑ Torque
Asymmetry
Diagonal shift of forces during propulsion
Quick, forceful & powerful poling
Injury can also be caused by:
Initiating motion from rest
↑ Momentum
Injuries are predicted to be similar to:
Distance Runners
Overuse
Asymmetry
Jumping
Other Poling Sports
Upper-Limb
Weight-bearing point-of-rotation
∴ ↑ structural competence of upper-limbs &
shoulders by:
↑ stroke mechanics
↑ weight & resistance training
↑ musculoskeletal care for shoulder-
dependent populations
↑ awareness of potential mechanisms of injury
prolongs athletic career
Left Pick-Plant Force > Right Pick-
Plant Force
Right Push-Off Force > Left Push-off
Force
Vertical Force >> Horizontal Force
>>