Musculoskeletal in sports medicine

John Butarbutar

Sports Medicine

• Etiology, diagnosis, treatment and prevention of disorders and injuries of athletes, as well as with the ideal methods of athletic training

Salter, Textbookof Disorders and Injuries of teh musculoskeletalSystem

Muscle disorder & injury

Hamstring strain

Composed of • biceps femoris• semitendinosus • semimembranosus

History

A noncontact injury , either acute or insidious onset. Strain injuries frequently are seen in athletes who run, jump, and kick. Avulsion injuries are seen in patients who participate in water-skiing, dancing, weight lifting, and ice-skating. The patient may report a popping or tearing sensation.

Physical

• Tenderness over the site of injury• Ecchymosis• A palpable defect may be felt with severe

strains, but swelling and the deep location of the muscle may obscure this finding in the acute stage.

• Pain with passive extension of the knee and with resisted knee flexion

Imaging

• Radiographs can rule out an avulsion injury from the ischial tuberosity

• When a confirmation or grading of a hamstring strain is necessary, magnetic resonance imaging (MRI) is the most sensitive test

3 grades of severity of hamstring injuries.

• First-degree strain is the result of stretching of the musculotendinous unit and involves tearing of only a few muscle or tendon fibers.

• Second-degree injury refers to a more severe muscle tear without complete disruption of the musculotendinous unit.

• Third-degree injury refers to a complete tear of the musculotendinous unit.

The American Medical Association (AMA)

treatment

• Protection, rest, ice, immobilisation , gradual mobilization, muscle stretching and strengthening

• Surgery

Test

Etiology

– Strength – Flexibility– Warm up– Fatique

Worrell, T.W., & Perrin, D.H. (1992)Journal of Orthopaedic and Sports Physical Therapy, 16, 12-18.

Motor units

2- The Mechanism of Force Generation in Muscle

Fiber Type ComparisonType I Type IIa Type IIb

ShorteningSpeed

slow fast fast

Energy System oxidative oxidative,glycolytic

glycolytic

Size small large largeForceProduction

low high high

AerobicCapacity

high medium low

AnaerobicCapacity

low medium high

Fatigability low medium high

Tissue

Greatest Riska) 2-joint musclesb) muscles that limit ROMc) muscles used eccentrically

Which consequences do you expect ?• Myasthenia gravis: autoimmune disease where antibodies

against the Ach receptors are produced• Muscular dystrophy: some proteins forming the muscle fibers

are abnormal. • Curare binds to the Ach receptor without activating them.

What are the effect of curare on the skeletal muscle? • The botulism toxin prevents the release of the

neurotransmitter into the synapse. • Nerve gas inhibits acetylcholinesterase present in the

synapse.

• Rigor mortis: why does the body stiffen shortly after death?

• How do muscles become fatique after several contraction ?

• What are the different effects between high intensity and long sustained exercise to the muscle ?

Tendon disorder and

injury

Achilles Tendon Injury

• Common site for injury and rupture • Symptoms include posterior heel pain with

stiffness• The tendon is thickened• Neovascularization might be involved in the

pain mechanism

mechanism

• Pushing off with the weight bearing forefoot while extending the knee (53%)

• Sudden unexpected dorsiflexion of the ankle (17%)

• Violent dorsiflexion of a plantar flexed foot (10%)

Arner and Lindholm ,Acta Chir Scandinavia ,1959

Examination

• Diffuse edema, bruise, palpable gap, 2-6 cm proximal to the insertion

• Calf squeeze test• Knee flexion test

presentation

• Sudden pain in the affected leg (feels like struck or kicked )

• Audible snap• Weakness of affected ankle

imaging

• MRI and US are methods of choice• Treatment• Rest, acitivy modification, NSAIDs,physical

therapy, surgical debridement, eccentric muscle training, bracing, heel inserts(Tasto et al 2003, Koenig et al 2004)

treatment

• Conservative with cast or splint• surgery

Pain mechanism

• Overuse and degeneration• Local hypoxia, micro trauma, impaired wound

healing may contribute• Pathology linked to degradation of collagen

and hypercellularity• Tendon contains no inflammatory cell

Tendon healing

• Occurs through extrinsic and intrinsic processes

• Divided into 3 phases– Inflammation (Day 0-7)– Repair (Day 3-60)– Organisation and remodelling (Day 28-180)

Organisation (28-180 days)

• Final stability acquired during this phase by the normal physiological use of the tendon

• Accompanied by cross linking between fibrils further increasing tendon tensile strength

• Complete regeneration never achieved– Defect remains hypercellular– Thinner collagen fibrils

• What is pain mechanism in rotator cuff tendinosis?

• How do you examine lateral epicondylitis, de quervainn, biceps tendonitis ?

Ligament disorders and injury

Anterior cruciate ligament rupture

Injury Mechanism

• 50-70% are noncontact injuries

• These usually involve planting, cutting and jumping

• This also commonly involves imbalances of body weight and malalignment of body position

History

• Noncontact injury• Audible pop• Immediate

hemarthrosis

Examination• Hemarthrosis• Lachman Test– Done at 20-30 degrees

of knee flexion

• Pivot shift Test• Drawer test

Lachman Test

1+ 0-5 mm of anterior displacement - sometimes with an end point 2+ 5-10 mm of anterior displacement - with no end point 3+ 10 mm of anterior displacement - with no end point

Comparison to other side is important

Xray Findings

• Tibial Spine Avulsion Fracture 8%

• Radiology. 1993 Jun;187(3):821-5.

MRI Findingsany discontinuity or signal change in the ligament is

indicative of ACL tear;

indirect signs of ACL tear: always look for signs of additional injury (meniscal tear, PCL tear,

LCL tear);

Pivot shift injury: combination of signal changes in lateral femoral condyle and posteror lateral tibial plateau:

abnormal slope of ACL

MRI Findings

MRI Findings

Treatment Options

• Surgery: Reconstruction– Restores stability, prevents further injury

• Conservative Treatment– older patients w/ isolated ligament injury who are

willing to moderate their activity will find non-operative treatment to be satisfactory in the majority of cases (over 80%)

Ligaments

• Made of dense fibrous tissue with the fibers in roughly parallel lines in the direction of functional need

• In most cases pliable but inelastic• Bind bones to bones• Supply passive support and guidance to joints

Ligaments

• May be so integrated into the joint capsule that they are indistinguishable as separate structures

• Reinforce joint stability• Generally loose enough to allow free joint

movement within a desirable range• Designed to prevent movement in a range

which would be damaging

Ligaments

• Blood supply– Poor in the ligament itself– Ligaments depend on diffusion to supply inner

fibers with nutrients– Vascular damage during injury can be particularly

bad for the healing of ligaments– Blood flow is facilitated by passive movements

after injury or surgery

Ligament Stress-Strain Curve

toe elastic plastic

failureyield point

Sensory Receptors in Ligaments

• May supply feedback to muscle tissue • Allow muscles to be recruited to assist in joint

stability

Failure Mechanisms

• Ligamentous Failure – The ligament itself fails– Characteristic of fast loading rates

• Bone Avulsion – The bone itself fractures or fails beneath the junction of ligament and bone– Characteristic of slow loading rates

• Failure at the Ligament-Bone Junction– The least common type of failure