Shoulder the burden – Phil Holland, Emma Torrance and Lennard Funk report on serious shoulder injuries in paddle sport to establish common mechanisms and patterns of injury
There has been a massive boom in paddle sports in the UK, with an estimated two million participants annually [1]. Paddle sports include canoeing and kayaking. The difference between the two is that in a canoe the paddler kneels and uses a single-bladed paddle (Figure 1), whereas in a kayak the paddler sits and uses a double-bladed paddle (Figure 2). White-water paddling is one of the most high-adrenaline and dangerous paddle sports: one in ten white-water paddlers report having a near-death experience and injuries are common – on average, paddlers sustain 4.5 injuries per thousand days paddled [2].
Paddlers use their shoulders in a unique way and place high demands on them. This makes the shoulder the most commonly injured joint among paddlers; up to 6 per cent of sea paddlers injure their shoulders during their lifetime and shoulder injuries are thought to be more common among white-water and competitive paddlers [2]. Patients with shoulder injuries take the second longest time to return to paddle sports (spinal injuries have the longest recovery periods) [2].
Despite the widespread recognition that in paddle sports shoulder injuries are common and often serious, little more is known. In this article, we report the largest case series of serious shoulder injuries among paddlers so far, to establish common mechanisms and patterns of injury.
The review
We reviewed 55 shoulder injuries in 52 paddlers. The mean age was 36 years (range 14 months), and 31 shoulder injuries were in males and 24 in females. Patient data was analysed pre- and post-procedure. A significant improvement in patient outcome scores was noted, with regards to QuickDASH (p = 0.0162) and Constant shoulder scores (p = 0.0078).
Eleven paddlers in our series were qualified British Canoe Union coaches, two paddlers were canoe polo competitors and two were flat-water sprinters. Twelve shoulders were injured in 11 paddlers who competed in slalom (six of these were competing at an international level); this included three shoulders in two paddlers who competed at Olympic level, and two shoulders in two paddlers who were injured while competing in or training for Olympic trials.
Thirty-five shoulder injuries were acute, with a definite precipitating event; 20 did not have a specific precipitating event (Table 1); 23 patients had labral injuries; six patients had acromioclavicular joint injuries; and 11 patients had chronic instability secondary to laxity and muscle patterning (Table 2). Thirty-five shoulders required surgery, which included 18 shoulders that required labral repairs (Table 3). Fifteen (79 per cent) of the injuries that occurred while paddling occurred while preventing a capsize or rolling after a capsize.
Patient histories
An example of a typical patient history is one patient who sustained an anterior labral injury caused by a first time dislocation during a capsize three years earlier. This was on a remote grade 4 Alpine river. The rescue required crossing the rapids and hoisting the paddler up a 10 metre cliff before the expedition doctor reduced her shoulder. She continued paddling white water but never regained confidence in her shoulder. She was planning a white-water trip to Nepal and sought an orthopaedic opinion as she knew a further dislocation could be life threatening.
Six injuries were in five international slalom paddlers. One paddler underwent humeral avulsion glenohumeral ligament (HAGL) repair and posterior labral repair, and then developed a post-operative frozen shoulder that required an arthrographic hydrodilatation procedure two months after surgery. He won a gold medal in the Olympics 12 months post-operatively. Another paddler had bilateral injuries and underwent a posterior labral repair in one shoulder and a 270° labral repair in the contralateral shoulder. These operations were one month apart. This paddler came sixth in the European Championships the year before his surgery and eighth in the European Championships eight months after his second operation. He subsequently went on to win a world cup. Two patients retired from international competition after their surgery. One patient had a SLAP and Bankart repair that required revision nine months after the index surgery. This patient retired from paddling to concentrate on high-level academic work. Another had a Bankart repair and retired from slalom competition – this paddler was nearing the end of her sporting career before the injury.
Paddle sports include many different disciplines that can involve competition, endurance or adventure. This makes the sport attractive to a wide demographic of people including athletes in their teens and sea kayakers in their sixth decade of life. The wide variety of shoulder injuries encountered reflects this.
Different strokes
One of the most common patterns of injury seen is a labral injury following a capsize. In response to an imminent capsize a paddler will perform a high brace. This requires abduction and external rotation of the shoulder to place the paddle above the head. The paddler then pushes the paddle down on the surface of the water to right themselves. There is a tendency for the paddler to lean back and externally rotate the shoulder because this moves the body mass nearer the boat’s centre of rotation and therefore makes the high brace easier (Figure 3). Unfortunately, this places the shoulder in a very vunerable position. In white water the water constantly moves under the paddle keeping it on the surface due to the hydrofoil effect. This can be desirable as it increases the force available to maintain an upright position; however, it also increases the force available for injury.
If a paddler does capsize they will attempt a screw roll. During a screw roll the paddler continually externally rotates and abducts the shoulder using the force of the paddle blade on the water to right the boat. When a paddler performs a screw roll they finish in an identical position to that of a high brace. When a paddler finds it difficult to roll they may try to increase the length of the stroke and the force available by further externally rotating and abducting the shoulder. Rolling is an activity that places the shoulder at a high risk of injury.
If a paddler does not successfully perform a high brace or a roll they will come out of their boat and swim. In white water or at sea this can be very dangerous and with a shoulder injury it becomes even more so.
When taking a history it is important to establish the remoteness of the environment that a paddler paddles in and what type of water they paddle on. The treatment plan should take this into account. Some white-water paddlers will want the risk of re-injury or dislocation reduced as much as possible and some loss of movement may not concern them; conversely, some competition paddlers may require a full range of movement to continue their career.
Paddlers find themselves at risk of shoulder injuries during other strokes. A bow rudder is a turning stroke that is often used. For this the paddle is placed at the front of the canoe and the force of the water moves the front of the boat towards the paddle. The shoulder is in an abducted and externally rotated position which places the paddler at risk of an anterior labral injury (Figure 4). A cross bow rudder is a similar turning stroke but the shoulder is in a maximally adducted position to reach to the opposite side of the canoe (Figure 5). This places the paddler at risk of a posterior labral injury. These mechanisms of injury were not seen in our series but they do demonstrate the extreme to which paddlers use their shoulders.
Injury prevention
When teaching new techniques, coaches often tell paddlers to consider the position of the body first, then the position of the canoe and, lastly, the position of the paddle blade. This has similarities to the approach that many therapists use for the prevention and treatment of limb injuries whereby core stability is considered before addressing the injured limb. In the hectic outdoor environment, paddle sport coaches can be heard shouting “body, boat, blade!” to a paddler. What they are doing is reminding the paddler to concentrate on core stability first, the canoe second and the shoulder and arm last. This approach should be encouraged to improve performance and prevent injury.
Treatment
A wide demographic of patients participate in paddle sports and the large variety of shoulder problems they have reflect this. Some paddlers will have chronic shoulder pathology while others will have injured their shoulder during a specific event. When treating an acute injury surgeons must identify the exact mechanism. Many injuries that occur during a capsize result in a labral tear and if these paddlers are to return to situations where a capsize is likely, surgery is often the safest treatment.
Following shoulder surgery paddlers can get back to the same level of paddling they were at before their injury. Complications following surgery do not always prevent paddlers from returning to sport. It takes a massive effort to overcome a shoulder injury and sometimes a paddler will make a conscious decision that this is not what they want to do. This appears to be the most common reason why a paddler may not return to their previous level of sport.
References
1. Mallabon, L. & Taylor, B. (2000) Paddlesport Review (commissioned by British Canoe Union), Manchester Metropolitan University
2. Schoen, R.G. & Stano, M.J. (2002) Year 2000 Whitewater Injury Survey. Wilderness Environ. Med. 13(2), 119–124
Authors
Philip Holland
Philip Holland is an orthopaedic surgeon with a special interest in the shoulder. He also regularly paddles white water all over the world. Philip has presented his research internationally and has written book chapters on upper limb surgery. He also reviews articles for The Bone & Joint Journal and The Annals of the Royal College of Surgeons of England.
Lennard Funk
Lennard Funk works as part of a large multidisciplinary upper limb unit at Wrightington Hospital, where his interests include complex shoulder instability, athletic injuries, surface replacement arthroplasty and rotator cuff disease. Len routinely treats elite and professional athletes.
He is honorary professor at the University of Salford, where he is the clinical lead for the postgraduate orthopaedic upper limb degrees. He is also involved in many research projects at the university. For more information, please see www.lenfunk.com.
Emma Torrance
Emma Torrance is the research and outcomes coordinator for the Manchester Arm Clinic at The Wilmslow Hospital. Her role is to manage a portfolio of clinical studies from research concept through to analysis and reporting. Emma works alongside the Manchester Arm Clinic consultants, upper limb fellows, medical students and external collaborators to aid and drive high-quality orthopaedic research.
