Composite Hockey Sticks and Wrist Injuries: The ECU Tendon
By Herb von Schroeder MD, Liam Plewes, and Steve McCabe MD
In the 1980s, the shift from laminated wood hockey sticks to aluminum-wood composite sticks with aluminum shafts and wooden blades was a technological advancement that changed the game. In the late 1990s, full composite sticks were introduced, balancing the flexibility and lightness of wooden sticks with the hardness and strength of aluminum.
Composite sticks have resulted in a faster pace of play. With more whip, less weight, and more bounce off the blade, wrist shots, snapshots, and slapshots can be placed in any corner of the net at exceedingly high velocities. The lightness and stiffness of composite sticks has led to more responsive puck control and passing accuracy.
Improved stick handling has further been boosted by hockey gloves with shorter cuffs that were introduced in the late 1980’s. These new gloves sacrificed the wrist protection offered by the long cuff but allowed for greater wrist motion and more precise puck control.
When shooting a puck, a player’s muscle energy travels from his or her entire body into the stick and on to the puck. The shaft of a composite stick bends like a spring for added force and some of that energy comes back to the player in the form of a reaction force. Energy transfer will find the weakest link along the chain. With the repeated work of shooting the puck and intense stick handling, the energy can weaken or damage the tendons or their tunnels at the wrist.
One of the tendons at the wrist that is more vulnerable to issues is the ECU (Extensor Carpi Ulnaris) tendon at the dorsal and ulnar corner of the wrist (Figure 1). The ECU is one of five tendons that control the wrist. All these tendons have their muscle bellies higher in the forearm. The ECU specifically controls the extension and ulnar deviation of the wrist during puck-handling and shooting, and also stabilizes the wrist. This tendon runs through a tight tunnel or compartment in a groove at the distal end of the ulna between the ulnar head and the ulnar styloid as it travels on to anchor in the back of the wrist (Figure 2a).
In some players, the tendon simply becomes overused and inflamed within its compartment. This is analogous to repeatedly running a rope over the edge of table resulting in fraying. The tendon can become sore and swollen, and more painful with shooting and stick handling. This overuse issue can be treated with rest, ice, anti-inflammatory medication, taping, corticosteroid injections and sometimes with surgery to clean the inflammation (synovectomy).
In other players, the groove in which the tendon runs (Figure 2b & c) may be shallow, or the fibrous roof can become stretched-out. This results in an abnormal side-ways motion of the tendon that further adds to pain, inflammation, and clicking. Players can often sense that there is something wrong and they can feel the tendon partially dislocating (subluxation) or fully dislocating and popping out (Figure 2c) and then back into its groove. The condition may not be painful or may simply settle. If it remains an issue, the first line of treatment is directed at the inflammation (rest, ice, anti-inflammatory medication, taping, corticosteroid injections). If unsuccessful, the treatment is directed at the mechanical issue by surgically reconstructing the soft tissues or the groove to restore the normal direction of pull of the tendon and stop it from running sideways.
The ECU tendon is assessed for subluxation with the player’s arm in the arm-wrestling position on a table. With the wrist in ulnar deviation (+/- gripping into the fist position) and while twisting the forearm through pronation and supination, the ECU tendon is visualized (Figure 1) and clicking, or frank subluxation is noted. The trainer or doctor can palpate the tendon in different forearm positions and try to pop the tendon in and out of its groove around the ulnar styloid. If symptomatic, this will reproduce the player’s pain and issues. X-rays are typically normal, but changes in the tendon may be seen by ultrasound or MRI. The condition should be differentiated from “TFCC” cartilage tears, or other issues on the ulnar side of the wrist that occur more commonly with direct trauma.
The technological advances of composite sticks and shorter gloves have changed the game of hockey and brought up the new issue of ECU tendonitis and subluxation. With routine care, most players can continue their season without issues, but persistent pain and clicking may need further management.
Figure 1. Photo of the back of a right wrist showing the ECU tendon.
Figure 2. Anatomical dissection of a right wrist showing (a) the ECU in its sheath, (b) the tendon taken out of its sheath showing the groove where the tendon travels between the ulnar head and ulnar styloid, and (c) the dislocated or subluxed position that the tendon can take before snapping back into place. Courtesy of Dr. Amit Gupta, Louisville KY.
Dr. von Schroeder is a Hand Surgeon, Associate Professor at the University of Toronto, and Consultant to the Toronto Maple Leafs and NHL.
Mr. Liam Plewes is a Kinesiology student at Queen’s University, Ontario.
Dr. McCabe is a Hand Surgeon and Associate Professor at the University of Toronto.