1. Judo & BJJ Shoulder Injury Prevention Ben Whybrow

2. Contents Prevalence & Epidemiology of shoulder injuries in Judo & BJJ. Atraumatic athletic shoulder pain with contributing factors. Basic principles of shoulder injury prevention. The programme with supporting evidence. References.

3. Athlete Build Body type of higher level judo & BJJ athletes is typically mesomorphic (athletic build, well developed muscles, hard, rugged, triangular, robust skeleton & thick skinned) allowing them to produce higher power, strength and muscle torque outputs so they can withstand and produce forces applied during fights (Lewandowska et al, 2011), (Baez et al, 2014). High levels of strength, endurance and power are essential for successful judo and BJJ performance (Detanico et al, 2015)(Andreato et al, 2013). Higher upper body aerobic & anaerobic power and capacity is associated with elite judo and BJJ performance (Franchini et al, 2011), (Correa da Silva, 2014).

4. The Shoulder in Judo & BJJ The shoulder is the most common significantly time-loss injured area in the upper body in Judo (Up to 22% of all injuries) (Pocecco et al, 2013, Kim et al, 2015). Over 40% of Judo athletes surveyed reported having a shoulder injury, the level of which varying from severe fractures and dislocations to small strains and bruises (Noh et al, 2015). Generally lower risk in BJJ, although most significant injuries in upper body occur in the shoulder (Scoggin et al, 2014).

5. Poecco et al, 2013. Injuries in judo: a systematic literature review including suggestions for prevention. BJSM. Sprains, strains and contusions generally the most common injuries in Judo. Dislocations more common in elite level adults, fractures more common in younger and lower level athletes. Majority of traumatic Judo injuries happen in standing fighting and usually as a result of being thrown, especially from Seio Nage techniques trying to prevent landing on their backs, landing on their shoulder or arm instead.

6. On review there is still very variable and inconsistent results in relation to: average injury risk, sex and age as risk factors, Rate of risk between competitions and training. Primarily due to the types and qualities of studies done, and lack of agreement on the definition of “injury”. Lower level competitions with a larger difference in performance levels between competitors general have higher injury frequency. Too soon return to judo and being thrown, as well as improper throwing techniques have been shown to increase injury risk as well. Took most information from retrospective competition studies.

7. Noh et al, 2015. Analysis of combat sports players’ injuries according to playing style for sports physiotherapy research. Journal Of Physical Therapy Science. Questionnaire study of 159 Korean combat sport college athletes (47 were Judo). Only 12% of reported combat sports injuries occurred during competition, 75% occurred during training/sparring. 45% occurred due to violent or over-training, 14% due to chronic fatigue, 14% due to lack of warm-up or cool down, 5% due to too much stress (Noh et al, 2015). Otherwise similar findings to previous.

8. Kim et al, 2015. Injuries in national Olympic level judo athletes: an epidemiological study. BJSM. 4 year prospective study on injuries at olympic training centre in South Korea (48 athletes). 95% of injuries recorded occurred at the training centre. Average injury rate was 4 per every 1000 hours of training (1 every 250 hours). Did show some differences between sex and weight groups but nothing majorly significant. Otherwise similar findings to previous.

9. Currently very limited evidence in BJJ, so unable to make any confident decisions in relation to injury rates and risk factors at all. Current suggestions are that “Pass” fighters are more at risk of developing shoulder injuries, as well as the vast majority of injuries occurring in training rather than competition (Del Vecchio, Foster & Arruda, 2016).

10. Currently no recordings or comparisons of Traumatic Vs Atraumatic

11. Traumatic Shoulder Injuries In Judo & BJJ Generally unpreventable (can only educate on break falling & appropriate submitting). In standing will generally occur while falling onto the shoulder directly or the arm. In ground fighting occurs if the shoulder is caught in a very awkward position or refusal of fighter to submit to shoulder lock causing it to dislocate/fracture.

13. So do atraumatic shoulder injuries happen? “Impingement is one of the most frequently described pathological shoulder conditions in general practice and sports medicine”. (Cools, Cambier & Witvrouw, 2008). “70% of rotator cuff tears occur in sedentary individuals” (Escamilla, Hooks & Wilk, 2014). Shoulder pathology very common in many non-contact sports e.g. baseball, tennis, volleyball, swimming etc. (Kirchhoff & Imhoff, 2010). Roughly 3% of all GP consultations are taken up by non-traumatic shoulder pain (Feleus et al, 2008).

14. How do they happen? Many reported athletic shoulder strains occur over time due to chronic overload and sport-specific adaptions, resulting in strength, flexibility and postural adaptions in the shoulder and kinetic chain (Cools et al, 2015). Many injuries in combat sports are caused by mechanical energy and primarily present as musculoskeletal injuries usually occurring due to overload from accident or overuse (Noh et al, 2015). Inactivity or excessively high inappropriate loading has been shown to increase injury risk, as well as rapid increases in training load over short time periods potentially resulting in a large amount of non contact soft tissue injuries (Gabbett, 2016). Fatigue, previous trauma and lack of physical preparation can all lead to a muscle having reduced ability to tolerate load going through it, hence it is placed under too much stress and injury can occur in acute or chronic situations (Rosenblatt, 2016).

15. Main Contributors In The Shoulder Dysfunctional glenohumeral and scapulothoracic kinematics along with weak or insufficient shoulder stabilising musculature can lead to humeral head superior migration, reduced subacromial space and hence impingement symptoms as well as other shoulder pathology (Cricchio & Frazer, 2011). Three possible major factors for recurrent shoulder injuries in overhead athletes: 1. Glenohumeral internal rotation deficit (GIRD), 2. Reduced rotator cuff strength (especially external rotators), 3. Scapular dyskinesis (especially scapular position and strength) (Cools et al, 2015).

16. Rotator Cuff in Judo & BJJ Judo & BJJ contests usually involved high intensity intermittent activity requiring overload of several muscles and joints especially including those around the shoulder (Saraiva et al, 2014). Judo athletes have been found to have lower ER:IR ratios (weak external rotators, strong internal rotators) compared to other athletes, which has been suggested to lead to shoulder problems (Ruivo, Pezarat-Correia & Carita, 2012).

17. Effects of Grip Fighting Grip fighting requires high levels of isometric and dynamic shoulder strength endurance, resulting in progressive fatigue of shoulder external and internal rotators after more than one match, and potential muscle damage (Detanico et al, 2015). Infraspinatus fatigues quickly during resisted arm elevation (Kai et al, 2012) as well as prolonged isometric gripping with supraspinatus (Alizadehkhaiyat et al, 2011), which commonly occurs in grip fighting.

18. The Role of the Scapular Muscles Shoulder stability is primarily provided by active muscle control requiring a fine activation balance between the serratus anterior and different sections of the trapezius (Veeger & Van Der Helm, 2007). In healthy athletes when glenohumeral muscles are fatigued initially the subacromial space is actually increased due to increased posterior scapular tilt, and upward and external rotation, hence greater serratus anterior and lower traps activation (Maenhout et al, 2015). Only measured in short term. Scapular stabilising muscles produce even or higher levels of activity during shoulder external and internal rotation, hence fatigue would lead to altered biomechanics and potential shoulder pathology (Schachter et al, 2010).

19. So they can cause the issue? Shoulder injury risk increases with abnormal scapular muscle firing patterns, weakness, fatigue or injury (Escamilla et al, 2009). Scapular upward rotation, posterior tipping and external rotation provided by serratus anterior preserves the subacromial space. Serratus anterior weakness/fatigue along with increased upper traps activation leads excessive posterior scapular tilt and elevation, resulting in reduced subacromial space and pathological symptoms (Cricchio & Frazer, 2011). Emerging evidence has shown that many athletes lack balanced strength in their scapular muscles (upper traps > serratus anterior/lower traps) which has been suggested to contribute to shoulder pain (Anderson et al, 2012).

20. But…… Still very variable and contradicting evidence on the cause-consequence relationship between shoulder pathology and scapular dysfunction (Cools et al, 2015).

21. Also… Although it has been previously hypothesised, no relationship has been found between general shoulder strength or external/internal rotator strength ratio and first time acute anterior shoulder instability/dislocation in the young athletic population. Suggesting that the muscular weakness comes after first time instability event/dislocation, not causing it (Roach et al, 2012).

22. The aims of the shoulder injury prevention programme Increase strength and control in rotator cuff muscles as well as certain scapular control muscles (Serratus Anterior & Lower Traps). Should be able to be done in any location without need for equipment (gym, competition arena, hotel room etc). Overall to reduce the amounts of atraumatic shoulder injuries. Doing this programme prior to a heavy gym or training session can act as a suitable warm up to increase muscle temperature to help increase tissue compliance and neuromuscular activation (Lewindon & Lee, 2016).

23. Exercises to be slow and with a light weight (1-2 Kg) Doing exercises slowly in an eccentric style leads to maintained supraspinatus fibre bundle length, compared to concentrics which lead to reduced fibre bundle length, allowing the tendon and muscle to sustain force over a greater length and possibly heal micro-trauma. Doesn’t change muscle function & ability at all (e.g. power, force etc) (Kim et al, 2014). Infraspinatus is best activated at low to moderate loads, posterior deltoid activity compared to infraspinatus increases beyond 2kg or 40% maximum voluntary contraction (Jo et al, 2015., Bitter et al, 2007). Little difference in infraspinatus activity levels when load is increased (Tardo et al, 2013). Shoulder muscle recruitment patterns do not change with increasing load (Tardo et al, 2013).

24. Train for endurance (High repetition, Low load) Most effective infraspinatus training should focus on endurance, high reps with low load (Bitter et al, 2007). Effective endurance training involves high volume, lower load, repetitions of 15+ and short rest periods (Lorenz & Morrison, 2015). Appropriate as will need continuous activity during prolonged grip fighting.

25. Even Back:Chest Workout Ratio Tight pectoral muscles reduces the amount of posterior scapular tilt and external rotation, hence reducing the subacromial space, and hence increasing the risk of shoulder impingement (Phadke, Camargo & Ludewig, 2009). If pecs are very strong but back muscles are weak they could pull the humeral head anteriorly and reduce the subacromial space. If anything better to do more back than chest.

26. Vary Method of General Arm Strengthening For example: For chest strengthening alternate between using dumbells, barbells and smith machine, as well altering body positions between standing, sitting and lying. Variation of training load reduces the monotony of training which can in turn reduce the risk of injury and illness (Rosenblatt, 2016).

27. To be done in addition to general chest, back and arm strengthening not instead of! Flexion movements lead to greater supraspinatus, infraspinatus, traps and serratus anterior activation, while extension movements lead to greater subscapularis activation, all increasing with load (Wattanaprakornkul et al, 2010). Bench press lead to increased supraspinatus, infraspinatus & serratus anterior activity, increasing as load increases, resisting anterior humeral head translation from pecs (Wattanaprakornkul et al, 2011). Rows lead to increased subscapularis and lower traps activity, increasing as load increases, resists posterior humeral head translation from lats (Wattanaprakornkul et al, 2011). Chest press and rows have been recommended in rotator cuff injury prevention programmes for other sports (Niederbracht et al, 2008). BJJ Competitors should have a high level of physical fitness before considering competing (Scoggin et al, 2014).

28. Maintain general body fitness & strength Consistently training at high workloads and developing high physical qualities generally reduces the risk of injury (Gabbett, 2016). General fitness training to enhance recovery and fatigue resistance may help minimise injury risk, by reducing rate of poor/un-safe techniques while fatigued (Mohammed et al, 2014). Increased strength and power in lower proximities reduces the amount of overload and then fatigue in the upper body when fully body movement is required (Prangley, 2016).

29. The stretch debate Long term appropriate stretching can be effective for soft tissue injury prevention as it can improve the torque-angle relationship around a joint and can increase eccentric muscle strength, but needs to be combined with other forms of training to be effective. Static stretches not appropriate prior to gym work or competition as stiff musculotendinous properties are necessary to produce effective powerful and fast movements, and to tolerate higher forces. Fast dynamic active stretching prior to exercise can help improve muscle force production, movement capacity and body temperature. Effects of prolonged static stretching post exercise still hypothesised and uncertain, though does give the athlete time to assess for any problems post exercise (Blazevich, 2016).

30. Rest Time Should allow roughly 24 hours between heavy shoulder gym sessions or training to allow muscle adaptions to overload to take effect, without risk of excessive soft tissue or bone loading stress.

31. Scapular Push Up Plus The Exercise: Get into a press up position and straighten your arms so that your elbows cannot bend, turn your hands slightly out to the side and have them shoulder width apart, make sure they are close to your chest. Then let your body drop down slightly so that your shoulder blades come together before pushing your body up as far as possible taking your shoulder blades apart and hold for roughly 5 secs, all the while ensuring that your arms remain straight. Once you have done one rep crawl slightly forwards, backwards or sideways and repeat moving position each time. Repeat for 1-2 minutes.

32. Method/Technique: Shoulder elevation above 60 degrees during a push-up exercise reduces the subacromial space, increasing the risk of impingement symptoms (Suprak et al, 2013), there is also higher serratus anterior activation at lower shoulder elevation (Cricchio & Frazer, 2011). Most amount of rotator cuff & serratus anterior activity when arms are externally rotated (Cho et al, 2014). Most effective serratus anterior activation with arms at shoulder width apart (Batbayar, 2015).

33. Supporting Evidence: Large amount of rotator cuff muscle activation during weight-bearing closed chain exercises (Suprak et al, 2013). Closed chain weight bearing exercises effective at stimulating dynamic stability with rotator cuff muscular co-activation (Swanik, Bliven & Swanik, 2011). Produces high amount of subscapularis (Swanik, Bliven & Swanik, 2011), infraspinatus and supraspinatus activity (Escamilla et al, 2009). Most effective scapular exercise for serratus anterior and lower traps activation, compared to upper traps activation levels (Anderson et al, 2012, Sciascia et al 2012).

34. Lateral Twist & Raise The Exercise: In a press up position have the arm to be exercised across the chest, it can be holding a light weight if necessary. Then slowly over at least 5 seconds take it out to the side straightening the arm with your thumb pointing upwards, as you do so turn your trunk so that you facing the side of the moving arm. Hold for up to 5 seconds before slowly relaxing down over 5 seconds, repeat 10-15 times each arm.

35. Supporting Evidence: During horizontal abduction there is higher activation of infraspinatus and supraspinatus compared to deltoid and upper traps is found in the lower ranges (Sciascia et al, 2012). Most supraspinatus activation achieved when external rotation is combined with horizontal abduction (Sciascia et al, 2012), as well as lower upper traps activation and high lower traps activation although does result in deltoid activation (Cricchio & Frazer, 2011). Externally rotating the trunk combined with horizontal shoulder abduction (lawnmower exercise) produces high serratus anterior and lower traps activation (Cricchio & Frazer, 2011). Closed chain shoulder exercises used to encourage proprioceptive and dynamic joint stability (Escamilla et al, 2009). The twist also adds in thoracic rotation which is necessary to assist scapular movement.

36. Scaption The Exercise: Start by standing with your arms straight by your side holding onto light weights with your palms facing forwards and your thumbs pointing out to side. Slowly raise your straight arms upwards pointing away from your body over 5 seconds, and hold them at roughly chest height for 5 seconds, then slowly lower back down to your side over 5 seconds. Repeat 15-20 times.

37. Method: Full can style produces least deltoid activity compared with empty can & prone abduction (Reinold et al, 2007), as well al higher infraspinatus, subscapularis and serratus anterior activity (Escamilla et al, 2009). Most effective infraspinatus and supraspinatus activity compared to deltoid activity at 30-90 degrees (Sciascia et al, 2012), peak supraspinatus, infraspinatus and serratus anterior activity occurs at 30-60 degrees of scaption/elevation (Escamilla et al, 2009). More rotator cuff activity at lower abduction ranges, more deltoid activation at higher abduction ranges (Escamilla et al, 2009).

38. Supporting Evidence: Lead to increased external rotator cuff eccentric activity without increasing internal rotator cuff activity at all (Niederbracht et al, 2008). Effective concentric & eccentric exercise for supraspinatus (Kim et al, 2014).

39. Side lye External/Internal Rotation at 90 degrees Abduction The Exercise: In a side lying position resting on your lower arm and with your upper leg bent with the foot flat on the floor. Rest your upper arm elbow on the bent knee, with the elbow bent at roughly 90 degrees. Slowly rotate your arm upwards as far as possible, hold for 4-5seconds then slowly lower and rotate your arm down, go as far as possible and hold for 4-5 seconds, then repeat. It should take a minimum of 5 seconds when rotating the arm up or down. You are looking to do 10-15 repetitions on each arm.

40. Method: Most amount of rotator cuff, rhomboids and lower traps muscle activity occurred in internal rotation exercises at 90 degrees of abduction (Alizadehkhaiyat, 2015). Having the arm supported at 90 degrees abduction reduces the amount of deltoid and upper traps activity, while maintaining high levels of infraspinatus and teres minor activity compared to un-supported (Tardo et al, 2013). Serratus anterior & lower traps are activated more during external rotation at 90 degrees abduction (Tardo et al, 2013), as well as teres minor (Escamilla et al, 2009). The full internal rotation position is similar to that of the “sleeper stretch” which has been shown to reduce posterior shoulder tightness and hence GIRD (Cools et al, 2015). More realistic to grip fighting or throwing arm position compared to 0 degrees abduction.

41. Supporting Evidence: Lead to increased external rotator eccentric activation, which can correct rotator cuff muscle imbalances (Niederbracht et al, 2008). Eccentric external rotation to maximal external rotation leads to high activation levels of infraspinatus and teres minor along with rotator cuff co-activation to prevent injury and promote shoulder stabilisation (Swanik, Bliven & Swanik, 2011).

42. Superman The Exercise: Get into an all 4’s position and ensure that your back is straight. Slowly raise one arm straight out in front of you while at the same time straightening and raising the opposite side leg until they are both parallel with your body. Hold for up 10 seconds then slowly relax down in unison. Repeat 10-15 times.

43. Supporting Evidence: More rotator cuff & scapular stabiliser activity in flexion exercise than bench press (Wattanaprakornkul et al, 2011). Shoulder flexion in a quadruped position leads to high serratus anterior and lower traps activation, although there is reasonable posterior deltoid activation as well (Tsuruike & Ellenbecker, 2015). Closed chain shoulder exercises used to encourage proprioceptive and dynamic joint stability (Escamilla et al, 2009).

44. The Core & The Shoulder Push up plus, Lateral twist & raise and the Superman are also very good core exercises. Important as an effective core will allow rapid transfer of energy from the legs to the upper body (Prangley, 2016). Most effective core strengthening exercises involve entire body movement (Burton & Cook, 2016).

45. Exercises Excluded The following activate upper traps over serratus anterior/lower traps: (Anderson et al,2012) Prone flexion/abduction/rows One arm row Shoulder Press Ring Fallout Standing external/internal rotation can lead to increased upper traps activity compared to side lying, due to postural hold activation (Cricchio & Frazer, 2011). Empty can exercise reduces the subacromial space leading to increased shoulder impingement risk (Escamilla et al, 2009). Prone external rotation at 90 degrees abduction produces higher deltoid activity compared to standing/lying, with no change in supraspinatus activity (Escamilla et al, 2009). Any open chain exercises above 120 degrees elevation lead to excessive deltoid and upper traps activity.

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