1. MUSCLE CRAMPS Dr. MG Roos

2. HISTORY 19 yr. female Start with exercise program Muscle cramps Brown belt in karate

3. MEDICAL HISTORY DVT at the age 17 Hypertension Dyslipidemia Fam. History father – CAB at the age 46, HT, Chol mother – HT, Chol, DM II,

4. TREATMENT Prexum 4mg. Ecotrin 81mg. Multivitamin Stopped Crestor

5. EXAMINATION BP 130/90 Neuromuscular = normal Vascular system = normal BMI = 34

6. Special Investigations Blood tests: FBC/LFT/TFT/UK+E/Ca/Mg/ Phosphate/chol/fasting s-glucose/ fasting insulin/clotting profile Duplex dopler

7. Biopsychosocial model Clinical: Muscle cramps Personal: She wants to start with an exercise program and loose weight Contextual: Risk factors / family

8. MUSCLE CRAMPS A muscle cramp is an involuntarily and forcibly contracted muscle that does not relax.

9. MUSCLE CRAMPS True cramps involve part or all of a single muscle or a group of muscles that generally act together Tetany all of the nerve cells in the body are activated, which then stimulate the muscles. Contractures result when the muscles are unable to relax for an even more extended period than a common muscle cramp. Dystonic cramps muscles are not needed for the intended movement but are stimulated to contract

10. True cramps Exercise associated muscle cramps Rest cramps: generalised involuntary muscle contractions in non-exercising muscles which are associated with a number of acute or chronic and congenital or acquired medical conditions Aetiology and risk factors

11. Rest cramps: in older adults, but may be experienced at any age. o Dehydration o Hypocalcaemia, hypomagnesaemia and hypokalaemia o hypothyroidism, o renal or liver dysfunction o Neuropathic conditions such as amyotrophic lateral sclerosis (ALS), peripheral neuropathies, and cramp-fasciculation syndrome Aetiology and risk factors

12. Numerous medicines can cause cramps. Diuretics; furosemide (Lasix), can induce cramps by depleting body fluid and sodium, potassium, calcium, and magnesium. Anti-cholesterol; statins (Simvastatin) Alzheimer's disease; donepezil (Aricept) Myasthenia gravis; neostigmine (Prostigmine) Osteoporosis in postmenopausal women; raloxifene (Evista) HT; nifedipine (Adalat) Asthma; salbutamol (Ventolin)

13. Withdrawal from medications and substances, including alcohol, barbiturates, other sedatives, anti-anxiety agents narcotics, and other drugs. Several vitamin deficiency states may directly or indirectly lead to muscle cramps. These include deficiencies of thiamine (B1), pantothenic acid (B5), and pyridoxine (B6). The role of deficiency of these vitamins in causing cramps is unknown.thiaminepantothenic acidpyridoxine Poor circulation - claudicationclaudication Aetiology and risk factors

14. TREATMENT Rule out all possibilities and Rx Diet Medication Stretching: Data are insufficient to draw any conclusion on the efficacy of calf stretching in reducing the frequency of muscle cramps

15. Pharmacologic treatment Quinine – 93 deaths since 1969 Diltiazem 30mg – reduction in freq/-int Vit B (Vit B6-30mg) 86% remission Neurontin – ALS (amyotrophic lat scleroses) no difference Mg – 90% no difference ?Baclofen/carbamazepine/trileptal – no clinical trails Katzberg 2009

16. EXERCISE ASSOCIATED MUSCLE CRAMPS (EAMC)

17. Definition EAMC is a syndrome of involuntary painful skeletal muscle spasms that occur during or immediately after physical exercise.

18. EXERCISE ASSOCIATED MUSCLE CRAMPS (EAMC) Presents as painful localised muscle cramping that occurs sporadic in different exercising muscle groups —usually calf, hamstring & quadriceps muscles

19. Not all athletes with muscle cramping suffer from EAMC. Many underlying medical conditions

20. EXERCISE ASSOCIATED MUSCLE CRAMPS (EAMC) EAMC is particularly common in endurance events aetiology of EAMC in athletes is still not well understood.

21. The first reports of muscle cramping related to physical activity were from labourers working on steamships and in mines in hot, humid conditions more than 100 years ago. In these early reports it was noted not only that muscle cramping occurred in the heat but also that cramps were accompanied by profuse sweating. These early anecdotal observations led to the development of the traditional ‘‘electrolyte depletion’’ and ‘‘dehydration’’ hypotheses for the aetiology of EAMC. Aetiology of EAMC

22. Hypothesis Dehydration and electrolyte depletion are often considered together (and recently together with muscle fatigue) as the ‘‘triad’’ causing EAMC. The key components of this hypothesis are that electrolyte depletion through excessive sweat (sodium) loss together with dehydration causes EAMC.

23. Evidence against Electrolyte & Dehydration Hypothesis No difference between pre- and post race serum electrolytes Drew N, MPhil Sports Medicine dissertation, University of Cape Town, 2006). Schwellnus 2010

24. Electrolytes & Localised symptoms Both electrolyte depletion and dehydration are systemic abnormalities, and therefore would result in systemic symptoms However, in EAMC, the symptoms classically are local and are confined to the working muscle groups.

25. Thus, the available evidence to date does not support the hypotheses that electrolyte depletion or dehydration cause EAMC Therefore an alternative hypothesis for the aetiology of EAMC has to be considered.

26. NEW HYPOTHESIS ‘muscle fatigue’ suggested that the development of ‘neuromuscular fatigue’ leads to abnormal neuromuscular control.

27. Muscle fatigue Altered neuromuscular control Muscle cramps

28. MUSCLE FATIQUE Repetitive muscle exercise Hot/Humid conditions Inadequate conditioning muscle energy Exercise duration Exercise intensity

29. Muscle fatigue Altered neuromuscular control Muscle cramps

30. Altered Neuromuscular Control Fatigue increases the muscle spindle afferent activity and decreases the Golgi tendon organ afferent activity which may result in altered neuromuscular control

31. Muscle fatigue Altered neuromuscular control Muscle cramps

32. Mechanisms by which fatiguing muscular exercise causes muscle cramping 1. Repeated stimulation of the 1a afferents through electrical stimulation or using the tendon tap (activating the 1a afferents) can induce cramping.

33. Mechanism by which fatiguing muscular exercise causes muscle cramping 2. Tension in Golgi tendon when stretched afferent reflex inhibitory input in a-motor neuron This is a plausible mechanism to explain why stretching is the most effective treatment of cramping This mechanism offers further support for the hypothesis that abnormal neuromuscular control is associated with EAMC.

34. Altered Neuromuscular Control Altered neuromuscular control may result in increased alpha motor neuron activity. Increased muscle cell membrane activity Therefore, as progressive muscle fatigue develops, there may be an increased risk of developing EAMC.

35. Altered Neuromuscular Control Muscle Fatigue increased muscle spindle afferent activity decreased Golgi tendon organ afferent activity Altered neuromuscular control increased alpha motor neuron activity Increased muscle cell membrane activity Muscle Cramping

36. Schwellnus. Br J Sports Med 2009;43:401-408 doi:10.1136/bjsm.2008.050401

37. TREATMENT AIM Reduce muscle spindle and motor neuron activity by reflex inhibition and afferent stimulation

38. PREVENTION No proven strategies Regular muscle stretching before and after exercise Correction of muscle balance and posture Adequate conditioning for an activity Mental preparation for the competition Avoidance of provocative drugs

39. OTHER STRATEGIES Incorporating plyometrics or eccentric muscle strengthening into training programs Maintaining adequate carbohydrate reserves during competition Treating myofascial trigger points

40. CONCLUSION Disabling Not all athletes with muscle cramping suffer from EAMC. Treat co-morbid conditions Multidisciplinary approach

41. References M P Schwellnus. Cause of Exercise Associated Muscle Cramps (EAMC) -- altered neuromuscular control, dehydration or electrolyte depletion? Br J Sports Med 2009;43:401–408 Martin P Schwellnus, Nichola Drew and Malcolm Collins Increased running speed and previous cramps rather than dehydration or serum sodium changes predict exercise- associated muscle cramping: a prospective cohort study in 210Ironman triathletes Br J Sports Med published online December 9, 2010 Hans D. Katzberg, MD Ahmir H. Khan, MD Yuen T. So, MD, PhDAssessment: Symptomatic treatment for muscle cramps (an evidence-based review) Am Ac of Neurology 2010;74: 691-696