Spring is here again and welcome after a particularly chilly winter. Now is the time when we dust off our running shoes, pull out the decaying swimmers, and take a new lease out on life!

One problem that rears it's head often at this time of year is that of seasonal allergies, rhinitis, and asthma. One problem particularly troubling to exercisers is that of Exercise Induced Asthma and/or Bronchospasm. This months blog follows this topic- remember management can be difficult and medical advice is wlays recommended. Happy exercising!

Exercise Induced Asthma and Bronchospasm

Exercise Induced Bronchospasm (EIB) is defined as a transitory ↑ in airway resistance that occurs following vigorous exercise. EIB represents a pathology different to that of classic asthma. It represents 6-12% of the general population, and 4-80% of the sporting population. The higher athlete prevalence is thought to be due to the high training loads in combined with the training environment of the athletes.

 

Exercise Induced Asthma (EIA) specifically refers to the individual with background asthma also triggered by exercise. It includes around 90% of asthmatics. EIA severity is ↓ by inhaled steroid treatment in a dose-dependent fashion. EIA is one of the first asthma symptoms and is the last to resolve after inhaled steroid treatment.

 

Symptoms of EIB:

Symptoms classically peak within 5-10 minutes after the cessation of moderate to intense exercise. It is suggested that during exercise surges in adrenaline are protective by stimulating bronchodilatation. After cessation of exercise adrenaline levels drop and mast cell mediator release occurs.

Symptoms of EIB are diverse, often not recognised and include:

• chest tightness
• wheeze
• shortness of breath
• dry cough

Others symptoms include prolonged difficulty in eliminating URTI’s, difficulty sleeping due to night symptoms & reduced performance.These symptoms will usually either resolve spontaneously or with the use of bronchodilators. 50% of patients with EIB are rendered refractory for the 2-4 hours after an event. The reason for this is unclear. It may be related to prostaglandins, and NSAID medications may abolish the refractory period. There may be a seasonal element to symptoms, and atopy is very important. There may be ↑ eosinophils in atopic athlete’s sputum. Winter athletes have been found to have ↑ neutrophils in their sputum (possibly because of respiratory tract trauma).

 

Diagnosis can be made via the use of:

• Clinical history (looking for the above symptoms)
• PEFR diary pre and post exercise and the bronchodilator response (although not entirely reliable and effort dependent).
• EVH challenge test (gold standard)
• Exercise challenge test
• Osmotic challenge tests- mannitol, hypertonic saline
• Allergen testing (SST, RAST, IgE) Total IgE serum levels can be used as a simple assessment of a patient’s allergic profile. Skin testing is for common allergens like dust mite, couch/rye/birch grass, and cats/dogs. If skin tests are positive (>3mm wheal) than should perform an IgE level plus a RAST test for that specific allergen.

 

Treatment

Management begins with a thorough assessment of asthma triggers including animal dander, house dust mites, mould, smoke, and pollen, changes in the weather or airborne chemicals.

 

Asthma and EIB should be distinguished from associated disorders that cause respiratory symptoms during exercise including: fixed airway obstruction, laryngeal dysfunction, gastroesophageal reflux, and vocal cord dysfunction (VCD).

Non-pharmacological therapy:

This should be used as adjunctive treatment, and there is no substitution for pharmacological therapy. Masks reduce severity of EIB; can recover 42 % of water at 16°C (more useful in colder countries). Nose breathing to increase resistance is not effective in all patients. It is difficult to do, especially during vigorous exercise (above 35 L / min). Exercise training effects still controversial. Increased fitness levels increase the threshold at which EIB occurs but won’t stop it.

Refractory period: This does not work in every athlete (~50%) and is not recommended as it may induce severe bronchospasm. Warm up before the actual exercise reduces asthma in subsequent exercise.

 

Pharmacological Agents:

Dependent on level of exercise. Medications just before exercise are adequate. Some patients may require treatment with daily asthma therapy. NB: ALWAYS CHECK MEDICATIONS WITH YOUR SPORTS PHYSICIAN AS SOME MEDICATIONS ARE PROHIBITED, AND MAY RESULT IN AN ADVERSE DRUG TEST FINDING.

 

β2-agonists

 These are effective at relieving of asthma symptoms, and have been reported to improve pulmonary function in 90% of individuals with EIB. They bronchodilate, ↑ air flow, ↓vascular permeability and moderately inhibit mediator release. Studies have demonstrated no ergogenic properties of any IOC approved medication when used in therapeutic doses by the permitted route (oral consumption of beta agonists does have an anabolic effect).

 

Cromones

Thought to block chloride ion flux into mast cells and prevent mast cell degranulation. Most effective within 2 hours of treatment and shown to prevent both early and late phase asthmatic reactions. It has no bronchodilating effects and cannot be used for acute episodes. Side effects: throat irritation, cough, transient bronchospasm. Precautions with abrupt withdrawal. Not restricted in sport.

 

Leukotriene antagonists

They can give protection against EIB and do not show tolerance (unlike β2 agonists). As once daily oral tablets, often have better compliance in younger individuals, and they can reduce corticosteroid requirements. They have around a 50% mean effectiveness in inhibiting post-exercise bronchoconstriction (possibly due to other inflammatory mediators being responsible for symptoms). Leukotrienes are released from eosinophils in response to an increase in osmolarity and could feasibly cause transient migration of eosinophils to the airways. While treatment with inhaled steroids decreases eosinophil number, steroids do not prevent the contractile effects of leukotrienes. Thus, EIA may still occur if there are sufficient cells left containing this potent mediator.

 

Inhaled corticosteroids

Improve asthma symptoms by reducing airway inflammation and bronchial hyper-reactivity. They inhibit multiple segments of the asthmatic cascade, suppressing the generation of cytokines, reducing the population of airway eosinophils, and preventing inflammatory mediator release. They do not have an immediate bronchodilator effect, and are not effective when used prophylactically prior to exercise. 4 weeks treatment with corticosteroids 400 micrograms daily reduced EIA severity and increased lung function.

 

The main role of corticosteroids is that of maintenance therapy to help control asthma, but in doing so they act to reduce bronchial responsiveness to exercise, thereby reducing the propensity for EIA. Often used on a regular basis, with sodium cromoglycate or nedocromil sodium given just prior to exercise. Side-effects of oral candidiasis and dysphonia can be reduced by mouth washing following administration. Others are hoarseness, cough, rhinitis eczema, GIT upset, arrhythmia, headache, light-headedness, thirst, taste disturbance.

 

Anticholinergics (not used in EIB)

This blocks vagal tone and reflexes which mediate bronchoconstriction. Used alone it is not a powerful bronchodilator. Its duration is approximately 6 hours and can be used to augment β2 agonists. Side effects include blurred vision, precipitation of glaucoma and a dry mouth. Theophylline has no role in treating EIA.

 

Happy birthday to BSEMS!

April marks 12 months since BSEMS opened its doors. Queenslanders have been through some pretty tumultuous times over this period, but have emerged stronger and more determined. Likewise, the BSEMS practice has grown and added to its core group of practitioners over this time. We are proud of our Multi-disciplinary clinic, and continue to aim to provide Brisbane and South East Queensland with a world class Sport and Exercise Medicine clinic. We are always open to suggestions as to how we can serve you better, so please feel free to leave your comments or thoughts.

This month’s blog topic covers throwing and overhead injuries. Whether you are a weekend warrior throwing around a park, or an elite athlete upper limb problems can result from the repeated action of throwing or using a racquet. Understanding the biomechanics of throwing helps you to appreciate the forces transmitted to the upper limb, and what problems can result from excessive use or poor technique.

 

Upper Limb Problems in Overhead Athletes

 

People of all ages are heeding the advice to become more active and participate in sport and recreation. So called ‘over head’ sports activities like throwing and racquet sports for the most part are simple, and require no special training to participate. However tremendous forces are placed though the upper limb during these activities, resulting in a combination of acute, and more commonly over-use injuries, that commonly present to General Practice.  This article explains the biomechanics of common over head activities, which explains the forces placed on the upper limb, and subsequent injury development.

Throwing Biomechanics

 

Throwing is a ‘whole body activity’ that commences with drive from the large leg muscles and hip rotation and progresses through segmental trunk and shoulder girdle rotation. It continues with a ‘whip-like’ transfer of momentum through elbow extension and through the small muscles of the forearm and hand, transferring propulsive force to the ball. Movement of the trunk and contact with the ground allow for maximal transfer of energy to the ball. (Water polo players can throw at only half the velocity of baseball pitchers.) The forces transmitted to the shoulder are lower during serving in tennis as the racquet dissipates much of the impact force, allowing a greater intensity of serving compared with throwing.

Throwing can be divided into 4 phases.

1) Preparation and wind up:

 

The major forces arise in the lower half of the body and develop a forward moving ‘controlled fall’. The weight is shifted back on the ipsilateral leg and the body rotates so that the hip and shoulders are at 90º to the target. During this phase lasting 500-1000 milliseconds, the shoulder muscles are relatively inactive.

Problems in any part of the ‘kinetic chain’ (e.g. injured hamstring) could impact on the eventual position of the upper limb, and precipitate injury.

2) Cocking:

 

The shoulder moves into abduction through horizontal extension and then into maximal external rotation (ER). In this position, the shoulder is ‘loaded’ with the anterior capsule coiled tightly in the apprehension position, storing elastic energy, and the internal rotators (IR’s) are stretched.

Toward the end of cocking the anterior shoulder restraints (inferior glenohumeral ligament and capsule) are under the greatest strain- with repetition these structures can become attenuated leading to subtle instability.

The cocking phase, which also lasts 500-1000 milliseconds, ends with the planting of the lead leg, with the body positioned for energy transfer through the legs, trunk and arms to the ball. Together, the first two phases constitute 80% of throwing duration.

3) Acceleration:

 

This consists of the rapid release of two forces: the stored elastic force of the tightly bound capsular fibrous tissue, and forceful contraction from the internal rotator muscles.

This generates excessive forces at the shoulder articulation, and the cuff muscles are highly active to hold the humeral head into the socket. Muscle fatigue can lead to loss of coordinated rotator cuff motion and decreased support. There are enormous valgus forces placed on the elbow, which tends to lag behind the inwardly rotating shoulder. A large degree of torque present on the elbow joint causes shearing forces to the articular cartilage.

This phase lasts 50 milliseconds, 2% of the overall time. It concludes with ball release at approximately the ear level.

4) Deceleration/follow through:

 

Not all of the momentum is transferred to the ball and very high forces pull forward on the glenohumeral joint following ball release, with a distraction force of 80% of body weight. The forces that must be countered are: humeral IR, glenohumeral distraction and elbow extension. This places large stresses on the posterior shoulder structures and elbow flexors.

Both the intrinsic and extrinsic muscles fire at near their maximum, in an attempt to develop >500N to slow the arm down. The spine and its associated musculature have a significant role as a force attenuator. Toward the end of the throwing motion, the torso begins to rotate forward, thus acquiring some of the kinetic energy of the arm, helping reduce the burden on the shoulder stabilizers which are attempting to stabilize the scapula and hold the humeral head within the glenoid. This phase lasts 350 milliseconds (18% of the total time).

 

Changes in throwing arm with repeated throwing:

 

At the shoulder, long term throwing athletes have an increased range of ER, because of repeated stress to the anterior capsule in the cocking phase, and stretch or breakdown of the inferior glenohumeral ligaments. This may lead to anterior instability of the shoulder and secondary impingement. Throwers often have more lax shoulders than non-throwers.

The normal strength of IR: ER is approximately 3:2, but in throwers this is exaggerated and over time lack of ER strength may increase vulnerability to injury.

At the elbow, repeated valgus stress could lead to a breakdown of the medial stabilizing structures (collateral ligament, joint capsule, and flexor muscles). This leads to an increased carrying-angle at the elbow. Less frequently, there may be anterior capsular strains, posterior impingement, or forearm flexor strains and a subsequent fixed flexion deformity.

Injuries associated with overhead activities

 

Shoulder

 

Typically overhead athletes will complain of pain during the throwing action. Repeated throwing often results in impingement, which can be superior or posterior; apprehension or subtle instability (typically anterior); and over time wear and tear changes to the rotator cuff and/or labral cartilage.

Pain during the wind up and cocking phase may be associated with lax anterior restraints, subtle instability and over time cuff tendinopathy.

Pain during the acceleration phase may be due to an internal rotation deficit, tight posterior cuff and internal impingement. Over time this could be associated with the development of a SLAP (Superior labral anterior-to-posterior) lesion.

A thorough biomechanical assessment, including analysis of throwing action, can determine problems with shoulder mechanics, and allow a targeted rehabilitation process. Often weakness in the ‘stabilizing’ rotator cuff muscles needs to be improved, along with scapulohumeral dysrhythm. A Sports Physician is ideally suited to examine such patients and coordinate rehabilitation. Investigations like ultrasound or MRI are occasionally warranted, and rarely operative intervention will be indicated. 

Elbow

 

The primary forces delivered to the elbow during throwing are a valgus and extension opening force. This produces:

• tensile stress to the medial compartment restraints (Ulnar collateral ligament, flexor-pronator mass, medial epicondyle apophysis, and ulnar nerve)

• shear stress to the posterior compartment (posteromedial tip of the olecranon and trochlea/olecranon fossa)
• compression stress produced laterally (radial head and capitellum).

Continued valgus and extension forces may produce olecranon tip osteophytes, loose bodies in the posterior or radio-capitellar compartment, and a kissing lesion (articular damage on the posteromedial trochlea caused by the olecranon osteophyte.  Subtle laxity may cause excessive soft tissue stretch with flexor-pronator mass tendinopathy, and ulnar neuritis)

Treatment typically involves a period of avoidance of aggravating activities, correction of biomechanics, appropriate strengthening rehabilitation, and a graded return to the provocative activity, monitoring for a return of symptoms.

 

Problems specific to young athletes:

 

Younger athletes are especially vulnerable to over head over-use injuries. Whilst they are exposed to the same forces as adults, growth plates remain open and are susceptible to stress related injuries, and may lead to long term deformity.

Problems in the shoulder include:

 

Traction apophysitis at the attachments of deltoid and pectoralis major

Rotational bone stress or stress fractures in the humerus

Shoulder impingement

Problems at the elbow include:

 

Medial epicondyle apophysitis

Lateral compartment osteochondritis dissecans

Traction apophysitis at the triceps attachment to the olecranon

In the sport of baseball, strict regulations apply specific to age, regarding the types of pitch allowed, as well as the number of pitches and innings permitted. This has been effective in reducing ‘little league’ shoulder and elbow pain. Most other sports rely on common sense in relation to appropriate training load. Unfortunately in this day of elite sport and high training volume at a young age, unrestricted load often results in over-use injury.

 

Elbow pain in Racquet sports:

Elbow pain is common in racquet sports, and may be due to dominant activity of the wrist extensors. The impact between the ball and racquet produces a significant amount of force, and the ‘shock’ transmitted to the arm depends on how hard the swing is; the speed of the incoming ball; where on the racquet face the ball hits; the quality of the racquet; the string tension; and the stroke mechanics. The ‘sweet spot’ is the area on the tennis racquet where the initial shock is at a minimum- if the ball misses the sweet spot there is increased shock transmitted to the hand, wrist and elbow.

Tennis elbow or lateral epicondylosis, is an overuse tendinopathy of the common extensor origin. Golfers elbow is the same pathology at the common flexor origin. Ways to reduce the shock at impact include:

Lower the string tension

Increase the flexibility of the racquet

Increase the size of the racquet head

Increase the weight (lead tape to the head and handle)

Increase the grip size

Grip higher on the handle

A larger grip size prevents the player from gripping the handle too tightly. It is only necessary to squeeze firmly on the grip during the acceleration phase of the stroke. Over time an eccentric strengthening programme has been shown to improve strength and function, and reduce pain. Adjunctive treatments such as corticosteroid injection, autologous blood injection or shock wave lithotripsy may have a role in recalcitrant cases.

An understanding of the biomechanics of over head sports allows the astute physician to determine injury likelihood, accelerate diagnosis, and to commence appropriate treatment and rehabilitation.

 

 

 

Happy New Year to all of our BSEMS patients, staff and friends.

 

We hope that 2011 proves successful in maintaining health and fitness. If you are struggling than feel very welcome to come and see one of our specialists- at BSEMS there is someone who can help get you back on track.

 

Welcome to Dr Thomas Gan

In mid January Dr Tom Gan will be commencing sessions at BSEMS. Tom is a senior registrar, meaning he is nearing completion of his Sport and Exercise Medicine specialty training. Tom has worked as a team physician for various elite sporting teams and has also been medical director for world class sporting events such as the Brisbane International Tennis tournament.

He has many professional interests including lower limb stress fractures, tennis injuries, cricket injuries, and trigger-point acupuncture.  He is available to provide consultations for a variety of paediatric and adult sports medicine conditions.

 

Tom will be working Tuesday mornings between 8am-12pm in the BSEMS rooms.

 

This year we are aiming to include a fact sheet from one of our practitioners to each blog. The fact sheets will be catalogued in our “Patient Info” webpage, under appropriately enough “Factsheets”.

For January we have provided an information sheet for patients and referrers regarding the appropriate preparation needed before a compartment pressure test is performed. This can help ensure that the test is performed correctly the first time and to reduce the chance of a false negative investigation.

 

 

Compartment Pressure Testing

Pre-test Preparation

 

Chronic exertional compartment syndrome is a cause for leg pain with exercise. The usual pattern is a gradual increase in pain during continuous exercise to a point when the athlete has to stop. Pain then takes between minutes to hours to go. Patients describe a feeling of hardness or fullness in their legs, and occasionally will notice lumps in the muscles. The condition is diagnosed by performing a compartment pressure test (CPT).

 

During a CPT the patient must be able to reproduce their leg pain as bad as they can get it. This means that in the days to weeks before the test is done, the patient should perform moderate level exercise (and not rest) so that they can reliably reproduce their symptoms on the day of the test. The patient will also guide the Sport and Exercise Medicine (SEM) Physician as to which compartments need testing, and they must pay attention to where they develop their pain (i.e. front of the leg, side, behind the shin bone, or more than one area).

 

The CPT involves injecting a small amount of local anaesthetic into the skin at the sites where the pressures will be tested. The patient will then jog/run/whatever needs to be done to bring on their symptoms, usually for 10-15 minutes. They then return to the room, and the SEM Physician performs the test, which involves inserting pressure manometer needles into the relevant muscles. One special needle has a catheter inside it, and this remains in the leg while the patient does specific exercises, whilst the pressure in the leg is monitored.

 

The test is very safe, but complications can occur- listed below. The test takes one hour. Typically the patient can drive or fly after the test is completed.

 

The SEM Physician always prefers to see the patient before arranging a time for the test, to ensure the test is done correctly right the first time, reducing the risk of getting a false negative result. If the diagnosis is confirmed, then the only real treatment is surgery (a procedure called fasciotomy, performed by an orthopaedic surgeon).

 

Complications

Compartment pressure testing is a relatively safe procedure, but is an invasive intervention, and some complications may result including (but not limited to):

Infection

Bleeding and bruising at the puncture sights

Possible (permanent) damage to underlying blood vessels

Possible (permanent) damage to underlying nerves, resulting in sensory or motor disturbance

Failure of the procedure

Risk of development of acute compartment syndrome requiring and urgent operation

Risk of development of a complex regional pain syndrome

 

 

 

Please feel free to discuss any questions or concerns you may have with the BSEMS staff and specialists.

 

Welcome to the first blog from BSEMS.  We hope to make this a regular occurrence, and a chance to pass on information on what is happening behind the scenes at BSEMS, as well as to provide information on topics provided by our specialists.

Since opening on the 7th April 2010, we have seen hundreds of patients from southeast Queensland with Sports and Exercise medicine issues. The first 5 months have been great, and we look forward to growing and providing a one-stop-shop for Sports Medicine. We have a multidisciplinary team waiting to help wherever we can. Every 1-2 months, we will endeavour to provide a topic of interest on the blog from one of our specialists.

Team coverage

Dr Matt Hislop is joint team physician for the Brisbane Broncos, and looks after the Reds Rugby Academy. The past few months have been a busy time with team cover.

Rugby League:

Dr Hislop was also happy to help with the screening and coverage of the two Queensland teams that played the curtain raisers for State of Origin game 2 held at Suncorp. Of course the real achievement of the night was when Queensland won the series for an historic fifth time.

The last few months have been interesting with the Broncos unfortunately falling short and out of finals contention for the first time in 17 years. Darren Lockyer's rib injury was quite significant, and it is a testament to him that he came close to returning to play. The timing of his injury was incredibly bad for the Broncos, but that is the nature of any sport. The Broncos no doubt are looking forward to some time off, before starting up again for the preseason.

Rugby Union:

The club rugby finals are on at the moment. It has been good to see many past Reds Rugby Academy members progressing to play Super 14 for the Reds- Poutasi Luafutu, Quade Cooper, Scott Higginbotham, Luke Morahan, and Ben Lucas to name a few. Dr Hislop is proud to be part of the team that helps young and upcoming rugby players in the best Academy programme in the country. His Academy role helps with screening, injury prevention, and management of injuries when they do occur.

Soccer:

Dr Hislop was privileged to be invited to help with medical cover for Everton FC when they completed their successful tour of Down Under in July. Thankfully the game was completed injury free, as the team had to board a flight back to the UK later that evening!

Dr Daelyn Vivers

BSEMS have been happy to welcome Dr Daelyn Vivers who has arrived from Perth recently.

She is settling in well and developing a dedicated patient following.

Dr Vivers is the newly appointed QAS Swimming doctor, and also looks after Water Polo.

She was involved in the coverage of National Short Course Championships at the Sleeman Centre, Chandler in July. Many of the well known Queensland swimmers have gone on to do well at the Pan Pacs Championship recently held in the USA, including Jessica Schipper, Sophie Eddington and Emily Seebohm.

Dr Vivers has recently undertaken a thorough review of exercise induced asthma and its management and is happy to manage any musculoskeletal problem.

Feedback

At BSEMS we are proud of our world class new rooms, great website, and our multidisciplinary team of specialists. We want to make life easy for our patients, by offering a one-stop shop for Sports and Exercise Medicine. (We do not have physiotherapy on site, but work closely with many of the excellent sports physiotherapists in our area.) Please peruse our website for more information on what each practitioner does. We welcome and value your feedback, both positive and negative.

Best regards until next blog!

Dr Matt Hislop

Practice Principal