Highlights from the recent Sports Medicine Australia conference 2019

The annual Sports Medicine Australia conference was held in the idyllic location of Twin Waters from 23-26th October 2019. Not only was it in a great location, but the academic program was jam packed with clinical gems.

Here is just a snippet of what was presented over the 3.5 days, for those wanting more, I was busy tweeting over the conference so head here to read more or search for the hashtag #ASICSSMA19

Hamstring strain injury prevention, rehabilitation & sports performance: David Opar, Ryan Timmins, Ferghal Behan, Kate Beerworth, Jack Hickey, Scott Hulm

Measuring strength, architecture & running mechanics for determining risk of hamstring strain injury- David Opar

Strength:

• not the golden bullet

• Although often studied, evidence of nordic strength is mixed

• more research unlikely to find "the answer"

• often measured due to increased accessibility

• eccentric exercise is more important than measuring eccentric strength: expose them to eccentrics

Architecture

• single prospective study only showing shorter fascicle length predisposing to injury, so replication studies needed. Timmins et al 2016

• more specific for biceps femoris injuries than knee flexor measure

• accessibility and experience major limitation

• still unknown if change in architecture influences risk of injury

• measure 2-3 times across season

Running mechanics:

• there might be some subtle differences in movement between injured and non injured but the difference is very small

• small number of injured participants

• laboratory based techniques limiting widespread application and research

• espoused in practice, but the evidence is lacking

• can it be changed, and if so is it time efficient to do so?

• Running fast (95%+) regularly more important than mechanics? Have them run fast!

• There is a sweet spot for exposure to fast running and likelihood of hamstring injury. Malone et al 2018

• Hamstring muscular tendon length similar across speeds, but relatively linear increase with maximal force and maximal negative work. 80% speed does not equate to 80% force and negative work, need to hit higher speeds!!

Ryan Timmins: I hate Nordics what else can I do?

Why might the Nordic work?

• Intensity of eccentric effort (supramaximal, eccentric overload with body weight)

• Activation (extent of BF & MH activity)

• Easy to plan: on field, no or minimal equipment needed, multiple people at once

• Plus other possible reasons eg increased in series strain & positive adaptations

• Razor curl as an alternative? Razor curls can increase nordic strength but did NOT increase fascicle length

Take home messages:

Nordics aren’t the only exercise option available- just the one that ticks the most boxes

Including additional exercises with the Nordic can complement training goals & balance b/w prevention & performance

However if using alternatives on their own (without Nordics)- program for the adaptation desired & determine what aspect is to be sacrificed

Dosage of Nordics: Ferghal Behan

Nordic hamstring and performance:

• improved sprint time (Ishoi et al 2018)

• 10m sprint time (Ishoi et al 2018, Siddle et al 2019

• change of direction (Siddle et al 2019)

Dose response

• minimum effective dose is different for eccentric strength & architecture

• low dosage enough for strength (2 x 4 reps once per week), higher volumes are required for changes in architecture

• higher dosage results in greater improvements

• Higher dosage also had higher amounts of DOMS

There is yet to be determined a minimal dosage for nordics

Summary

• High exercise doses not required for strength or fascicle length

• minimum effective dose varies for both

• minimum effective dose for performance?

• high dosages may increase pain

• find the "goldilocks" prescription zone

Scott Hulm

When to start running post hamstring injury?

• Respect tissue healing!

• Return to running within 4 days of injury resulted in significantly higher risk of subsequent injury

• Notably extending this off legs period >4days did not delay RTP time (Stares et al 2018)

"To begin with the end in mind"

• Respect tissue healing/objective criterion- load alternatively early

• Limit deconditioning - plan backwards to build chronic low speed/HIR loads/aerobic fitness (monitor key clinical tests)

• Re-develop acceleration & horizontal force capacity- sleds/resisted running/RSA

• accumulate & periodize adequate HSR volumes- prepare for "worst case" scenario

• conscious distribution of multiple high velocity exposures >85%-100% "run fast & often". 5-8 sessional exposures of maximal velocity over 4weeks had an 85% decrease in HSI

References

• Timmins, R. G., et al. (2016). "Short biceps femoris fascicles and eccentric knee flexor weakness increase the risk of hamstring injury in elite football (soccer): a prospective cohort study." Br J Sports Med 50(24): 1524-1535.

• Malone, S., et al. (2019). "Can the workload-injury relationship be moderated by improved strength, speed and repeated-sprint qualities?" J Sci Med Sport 22(1): 29-34.

• Behan, F., et al. (2019). "The dose response of Nordic hamstring exercises on biceps femoris long head architecture and eccentric hamstring strength." Journal of Science and Medicine in Sport 22: S71-S72.

• Ishoi, L., et al. (2018). "Effects of the Nordic Hamstring exercise on sprint capacity in male football players: a randomized controlled trial." J Sports Sci 36(14): 1663-1672.

• Siddle, J., et al. (2019). "Acute adaptations and subsequent preservation of strength and speed measures following a Nordic hamstring curl intervention: a randomised controlled trial." J Sports Sci 37(8): 911-920.

• Stares, J., et al. (2018). "How much is enough in rehabilitation? High running workloads following lower limb muscle injury delay return to play but protect against subsequent injury." J Sci Med Sport 21(10): 1019-1024.

Phil Glasgow: Optimizing load to maximise outcomes

Rehab= training in the presence of injury

Instead of injury prevention= increased robustness

Context=>Outcome

• Injury prevention=Increased robustness

• Rehabilitation=Effective return to sport

• Performance enhancement=Improved performance

• Early loading is Optimal loading

• Principles of training do NOT change when someone is injured

• Important to ask the patient what training they have done in the past? Even if it is a long time ago, they will still have the myo nuclei present, and will tend to adapt faster to re loading

Optimal loading is:

• early but controlled

• Ligament recruitment

• Multiplanar

Ligaments injuries:

• Early mobilization improves short term short term functional outcome. Unloaded ligaments are half as stiff

Bone injuries:

• sufficient overload is needed

• novel loading (multidirectional load i.e. torsion)

• dynamic

• load little and often: recent player with bone injury they trained him 6 times per day

• high frequency

• site and activity specific

Assessment items to consider

• ask your athletes about why they think they are hurting: what is their understanding of their condition?

• Ask about more than just pain: think of all the things that can influence pain (sleep, stress, anxiety, fear ect)

• Measure the functional state of the pain system? Assessing temporal summation via exercise reps (ie movement evoked pain)

A.Prof Tash Stanton “Pain in athletes- integrating new insights from pain neuroscience into assessment & treatment

Treatments informed by pain science

• Increasing pain knowledge

• Pain science based movement prescription

• Using sensory input to our advantage

Words hurt: Use language to HELP our athletes in pain

• "Movement will be painful at first- like a sprained ankle - but will get better as you get active"

• "Our tissues heal best through loading- gradually increasing your activity is the very best thing you can do"

• "You knee/hip/back is strong & robust- let's take it out for a test drive"

• Message:“Movement is the best thing for you to help you heal, and you are safe to move”

The expectation of how pain influences performance...influences ACTUAL performance

• Negative group: "pain disturbs cognitive processes like visual processing and memory"

• Positive group: "pain enhances cognitive processes like visual processing and memory"

• Positive group showed significant improvement in cognitive task

(Sinke et al, Cortex 2016)

Applying pain based movement prescription for athletes in pain:

• Unpair the movements that hurt with that EXACT movement

• if elbow extension during a backhand is painful, find new ways of achieving elbow extension that do not mirror the exact tennis stroke motion ie yoga downward dog, dance, tai chi

• Use different movement pattern to create a new representation and to promote increased diversity in representations

Key takeaways

• Pain is there to protect, it doesn't necessarily tell us about damage

• this often means that searching for peripheral "cause" is not fruitful

• just because you feel pain doesn't mean you are injured

• Our systems can become over-protective

• Pain occurs when evidence of the need to protect outweighs the evidence of safety

• Our words matter

• Understanding pain is an effective treatment

• We can use movement to help our system "unlearn" associations between pain and activity

• We can use vision and sound to our advantage

Phil Glasgow: Training load monitoring & management in athletes

• Robustness: the capacity to consistently engage in training & games with maximal effort

• Important to look at what you need to improve in an individual in addition to their injury for which you are treating them. Once you have identified these pillars of improvement, you then need to establish how to assess & monitor these.

For example you identify the following areas for improvement in an athlete, with the ways to measure listed:

1. Neural activation: hand held dyno, rate of force development (RFD), jumps

2. Motor control: movement quality 3C's, adaptability, outcome/execution

3. Mutli-segmental mobility (rotation): tension arc, RFD, sport specific pattern

4. High speed running: distance, density, Vmax

5. Psychological factors: POMS, hyper vigilance, anxiety

6. Posterior chain strength: hand held dyno, nordic hamstring strength, isokinetic dyno

Things to consider in all injuries

1. Mobility

2. Strength/power

3. Movement/stability

4. Conditioning/load

Hamstring & groin example in Rugby Union player

Mobility

Tissue quality & flexibility

Thoracic spine:

• Extension ROM > neutral

• Seated rotation ROM >30 deg, symmetry <10%

Hip/Low back mobility:

• Sit & reach: Min 6-16, SD Flag >1SD

Hip mobility

• Hip IR 90/90 >20deg

• Hip ER 90/90 >45deg

• ASLR: 70-90deg

• Hip ext: 0-10deg

• Symmetry <10%

Tension arc

• Hip ROM ABD/ADD + IR/ER

• Normal: 160 deg

• Kicker: 180 deg

• Symmetry <10%

Movement/stability

• Skipping a rhythm

• Plyometric: Hop/Bound: rotational, lateral, linear

• Absolute speed

• Multi-directional speed

• Squatting, lunging & hinging

Strength/power

• Eccentric strength Nordboard: 400-500N, <10% asymmetry

• Concentric strength: Groin squeeze 200-300mmHg, Symmetry <10%, SD flag >1SD

• Eccentric/concentric strength: Posterior chain: 2 leg RDL 1.5xBW, 1 leg RDL 0.75 x BW, Rear leg elevated split squat: 0.75 x BW

• Unbreakable in the following positions: Hamstring 90/90 position, Hip 90/90 position

Conditioning/Load

• Load: Acute:Chronic spike for: distance, high speed running distance, acceleration distance, acceleration efforts, plyos

• Max Velocity: Achievability & Consistency: 2-3 x 90% every 7-10 days

• Kicking load & consistency

• Repeated sprint attempts & recoverability

• Exposure consistency: distance, high speed running distance, multi direction, acceleration, plyos

Shoulder & rotator cuff in Rugby Union player example

Mobility

Tissue quality & flexibility:

Thoracic spine:

• Extension ROM > neutral

• Seated rotation ROM >30 deg, symmetry <10%

Rotator cuff:

• External rotation: 90 deg at 90/90

• Internal rotation: 30 deg at 90/90

• Symmetry <10%

Scapular motion

Movement/stability

• Technique: scrum, line-out, maul, tackle, carry, clean out

• Up push, pull & rotation

Strength/power

• Reactive strength: Force plate: explosive push up, reactive strength index & force

• Concentric strength: Int & Ext rotation: Handheld dyno 90/90 position, 1:0.8 strength ratio, <10% asymmetry

• Push & Pull strength: Horizontal/vertical pull: 1.2-1.5 x BW, Horizontal push: 1.2-1.5 x BW

• Unbreakable: External rotation in 90/90 position, Internal rotation in 90/90 position

• Isometric testing: Force plates: ASH test

Conditioning/load

• Tri-planar shoulder cuff capacity

• Body composition

• Collision load: scrum, maul, tackle, carry

Joanne Kemp- Evidenced based management of Hip-related pain

Things to consider to formulate diagnosis during physical examination

1. Pain location

2. Palpation

3. Special tests

Differentiating between hip and low back

• Walking with a limp (7x more likely hip than spine)

• Pain in groin/anterior hip (7x more likely hip than spine)

• Reduced hip IR ROM (14x more likely hip than spine)

• No change in symptoms with repeated lumbar movement (SN 92% ruling out lumbar spine)

• Negative extension/rotation lumbar spine (SN 100% ruling out lumbar spine)

• Negative SLR (SN 97% ruling out lumbar spine)

• Negative slump test (SN 87% ruling out lumbar spine)

• Negative thigh thrust (SN 82% ruling out lumbar spine)

• No pain over SIJ (ruling out SIJ)

(Thorberg 2018

No pain in anterior hip/groin? It will NOT be intra-articular hip related nor likely to be hip flexor, adductor or inguinal related pain

Special tests

• FADDIR to rule OUT having intra articular hip issues

• FABER- poor to fair test to rule in and rule out

• Adductor squeeze test: positive you can be confident that it is adductor related pain BUT a negative test doesn’t rule out adductor related pain

Strength

• Adductor and extension weakness in Both sexes

• Abductor strength more important to measure in WOMEN

• Re-measure all strength at 6-8 weeks, but measure the most impaired at every visit.

• Joanne doesn’t measure hip external and internal strength anymore- some argue quadratus femoris plays an important role, but it’s action is more as an adductor.

• Joanne uses make AND break testing

ROM:

• Greater hip flexion range is most important to measure- normal 110-120

• Hip internal rotation doesn’t particularly change post hip operation.

• Measure hip flexion range at the start and end of treatment

• Internal rotation: measure at initial but UNLIKELY to change with treatment

Functional assessment

• single leg hop for distance

• Single leg bridge to fatigue

So as I mentioned at the beginning, this was just a small taste of what was offered over the week. For those wanting to read more, head to Twitter here or search for the hashtag #ASICSSMA19

Hope to see you next year in Melbourne 2020!