Epidemiology
- Incidence of shoulder, knee, and spine injuries appear to increase with greater training volume
- Freshmen swimmers suffer the most injuries compared with more experienced swimmers
- due to a substantial increase of training volume
- Freshmen swimmers suffer the most injuries compared with more experienced swimmers
- Females had significantly more injuries to the knee, back/neck, shoulder, hip, and foot
- History of injury to the same anatomical location and history of injury at other anatomical sites, both correlate to incidence of future injuries
- Pain and injury are greater in swimmers with a poor stroke technique
- See Injury Etiology
Injury Prevention
- Stroke-specific mechanics instruction, monitoring, and timely feedback
- Also see Skill Acquisition and Proficiency
- Carefully program and monitor training volume, intensity, and duration
- Minimize overuse injuries and identify athletes at risk
- Do not subject swimmers to irrelevant/incorrect training principles
- Understand dose-response relationship of fitness and risk of injury
- See Running Example
- Teach swimmers how to recognize injury (pain) and the importance of reporting injury so it can be properly treated before it becomes worse
- Coaches should identify early signs of injury
- Stroke alterations occur in the swimmer with a painful shoulder (possible subacromial impingement)
- Wider hand entry
- Dropped elbow in the recovery phase of the freestyle stroke
- Externally rotated shoulder when hand close to thigh
- Early hand exit or shortened pull-through phase
- Abnormal kicking mechanics can often be seen in swimmers with knee pain
- Swimmers with medial patellar facet pain keep their hips more abducted and utilized greater hip and knee flexion
- Swimmers with MCL pain derotate and plantar flexed the ankles as the knees extended
- Swimmers with knee pain performing the breast stroke showed high angular velocities at the hip and knee and increased external tibial rotation
- Stroke alterations occur in the swimmer with a painful shoulder (possible subacromial impingement)
- Evaluate athletes to determine individual strength, endurance, or flexibility deficits.
- Functional / ROM
- Posture
- Common postural problems with swimmers include
- forward head, thoracic kyphosis, decreased cervical lordosis
- rounded shoulder posture
- protracted scapulae, and internally rotated/anterior humeral head
- Issues associated with this posture include
- restricted anterior shoulder musculature
- lengthened and weak medial scapular stabilizers
- tight glenohumeral posterior capsule
- weak anterior cervical flexors
- Common postural problems with swimmers include
- Potential Common Impairments
- Postural deviations
- Tight anterior chest musculature
- Hypomobility of the thoracic spine
- Loss of joint mobility or excessive joint mobility
- Tight posterior capsule
- Impaired strength and endurance of the rotator cuff and scapular stabilizers
- Dry land conditioning program
- Strengthening, stabilization, and flexibility
- Shoulder
- supraspinatus, serratus anterior, rhomboids, lower trapezius, and subscapularis
- Knee
- vastus medialis obliquus
- possible hamstring stretch if inflexible
- Hip
- possible stretch for hip external rotators, if hip internal rotation is inadequate
- Possible hip flexor stretch if inflexible
- Spine
- Abdominal strengthening
Rehabilitation
- Athletic Trainer
- Diagnosis
- Possible rehab/therapy when appropriate
- as determined by athletic trainer
- Ice therapy up to 1 week
- Swim Training
- Prolonged warmup
- Temporarily reduce training distance and frequency
- Active rest by temporary avoidance of strokes and positions that cause pain
- typically freestyle and butterfly
- Alter strokes more frequently to reduce stabilizer fatiguing and repetitive shoulder stresses
- Avoid use of hand paddles, kick board, and surgical tubing
- Use swim fins to enhance the propulsion from the legs, so stress on shoulder can be reduced
- Dry-land exercise should be modified or eliminated if it irritates injury
- Contingency (if pain persists)
- 3-day period of absolute rest is recommended
- Athlete should then be reassessed prior to resuming modified training
- Evaluation by physician (sports medicine or orthopedic surgeon) if pain persists upon resumption of training
- Less common more serious problems should be ruled out
- 10-14 day course of Anti-inflammatory medication may be recommended
- Reevaluation by physician if treatment is not successful after 2 weeks
- Subsequent physical therapy may be indicated
Shoulder
- Risk Factors
- Glenohumeral laxity with subsequent shoulder instability
- 20% of swimmers may have generalized ligamentous laxity
- Both genetic and acquired components
- Acquired anterior laxity allows for excessive external rotation
- but places greater demand on rotator cuff and long head of biceps
- as to reduce humeral head elevation and anterior translation
- but places greater demand on rotator cuff and long head of biceps
- Overuse and fatigue
- Fatigue combined with glenohumeral laxity leads to excessive humeral head migration
- Example:
- Fatigued serratus anterior fails to stabilize the scapula in upward rotation
- Scapula fails to protract and upwardly rotate and the subacromial space may be compromised
- The space between the humeral head and glenoid increases
- contributing to more laxity
- Fatigued serratus anterior fails to stabilize the scapula in upward rotation
- Impaired posture
- Muscular imbalance or neuromuscular control
- Specific populations
- Females have shorter arm strokes and may have greater risk of overuse injury due to greater arm revolutions per lap
- Tendonitis can first occur in adolescents with long arms that are not heavily muscled
- They may be in the middle or end of a growth spurt
- Long limb length provides an advantage, but muscles, tendons and joints are not yet fully developed
- Glenohumeral laxity with subsequent shoulder instability
- Injuries
- 91% out of 80 young elite swimmers (13-25 years old) reported an episode of shoulder pain
- 84% demonstrated signs of shoulder impingement
- 69% show signs of supraspinatus tendinopathy diagnosed by magnetic resonance imaging (MRI)
- Swimmer's Shoulder
- Subacromial impingement
- tendonitis, bursitis, capsulitis, or arthritis
- Biceps tendonitis
- Rotator cuff tendonitis
- typically affecting supraspinatus
- Sometimes symptomatic glenoid labrum fraying
- Subacromial impingement
- 91% out of 80 young elite swimmers (13-25 years old) reported an episode of shoulder pain
- Stroke Techniques
- Body roll:
- Shoulders and hips roll equally about 45 degrees
- Places arms under body and close to the planes of the scapula
- Emphasizes shoulder adduction over extension
- Distributes work more equally between internal and external rotator muscle groups
- Reduces the stress of soft tissue structures in the anterior shoulder region
- Reduces scapular protraction
- Reduces demand on scapular muscle, particularly the serratus anterior
- Lack of body roll
- Cause the humerus to compensate by moving into further horizontal adduction for adequate propulsion
- Emphasizes shoulder internal rotators which may increase risk of over-use injuries to the shoulders
- A hand entry that crosses the midline of the long axis of the body causes impingement of the supraspinatus and the long head of the biceps.
- Excessive body roll
- May cross the midline of the body during the pull through phase
- Increased horizontal adduction can lead to impingement
- Bilateral breathing may help some swimmers who have asymmetric body roll
- Shoulders and hips roll equally about 45 degrees
- Elbows bend upon entry
- Keeping arms straight delays propulsion and overloads shoulders increasing risk of developing an over-use injury.
- Body roll:
Knee pain
- Risk factors
- Second most reported source of injury in competitive swimmers
- A study of Elite swimmers showed the rate of knee injuries was 0.17 for every 1000 hours of swimming
- Patellar instability, subluxation, or maltracking (Quadriceps conditioning abnormalities).
- Breaststroke
- Knee pain in breaststroke swimmers correlates with the number of years of training, the volume of training, the caliber of the athlete, and increasing age
- Overuse in breaststroke swimmers contributes to knee pain and injuries
- Breaststroke has the greater incidence of knee pain compared to all other swimming techniques
- > 10 fold risk over freestyle
- Injuries
- 86% of competitive breaststroke swimmers had at least 1 episode of breaststroke related knee pain
- medial compartment of the knee
- anterior knee pain also common
- strain injuries of hip flexors, adductor magnus and brevis
- 86% of competitive breaststroke swimmers had at least 1 episode of breaststroke related knee pain
- Kick Techniques
- Hip Adduction in breaststroke
- breaststroke generates higher valgus loads due to adducted hip position
- higher risk of injury when hip adduction angles are <37° or >42° at initiation of kick
- Whip Kick
- Increased strain of MCL due to high valgus load
- Flutter Kick in freestyle swimming
- Overuse resulting in patellofemoral overload
- Wall push-off
- Knee in high degree of flexion during starts in turns may result in patellofemoral overload
- Hip Adduction in breaststroke
Spine
- Risk factors
- Undulating motion of breaststroke and butterfly
- Training intensity and volume
- Use of training devices such as fins, kick boards, or pull buoys
- May produce excessive hyperextension of the lumbar spine
- No sex differences
- Injuries
- Swim athletes have greater incidence of degenerative disk changes compared to control group
- Incidence of low-back pain
- 33.3%-50% of butterfly swimmers
- 22.2%-47% of breaststroke swimmers
- Prevalence of demonstrated degenerated disks at various levels
- 68% of elite swimmers (mean age 19.6 years)
- 29% of recreational swimmers (mean age 21.1 years)
- Elite swimmers most frequently injure L5-S1
- Spondylolysis and possible spondylolisthesis
- Muscle and ligament sprains
References
Becker, TJ (1984). The Coaches Guide to Bicepital Tendonitis. ASCA 1984 Yearbook. 71-78.
Chase KI, Caine DJ, Goodwin BJ, Whitehead JR, Romanick MA (2013). A prospective study of injury affecting competitive collegiate swimmers. Res Sports Med. 2013;21(2):111-23.
Rushall BS (2013). Relevant Training Effects in Pool Swimming: Ultra-short Race-Pace Training (Revised), Swimming Science Bulletin, 40b http://coachsci.sdsu.edu/swim/bullets/ultra40b.pdf
Rushall BS (1998). Basic Training Principles For Pre-Pubertal Swimmers, Swimming Science Bulletin, 23
Tovin BJ (2006). Prevention and Treatment of Swimmer's Shoulder. North American Journal of Sports Physical Therapy, 1(4): 166-175.
Wanivenhaus F, Fox AJS, Chaudhury S, Rodeo SA (2012). Epidemiology of Injuries and Prevention Strategies in Competitive Swimmers. Sports Health. May 2012; 4(3): 246–251.