Sports Medicine SPMD3052 Classification of Injuries

The two cause of injury are?

-Extrinsic: direct blow, collision, impact

- Intrinsic: muscle forces, joint leading

What causes acute injuries?

Occur at a high velocity and are uncontrolled impacts resulting in macro-trauma

what causes overuse injuries?

Micro-trauma

Ligament function

To provide passive stability and guide what directions of motion are available at that joint.

Grade 1 Ligament sprain

Disruption of some collagen fibres.

Symptoms of Grade 1 Ligament sprain

-Localised tenderness on palpation

- Minimal inflammation

- No increased joint laxity

- Little function deficit

Grade 2 ligament sprain

disruption of considerable proporaion of collagen fibres (partial tear)

Symptoms of Grade 2 ligament sprain

- Significant tenderness on palpation

- Can be considerable inflammation involving the whole joint (effusion)

- Increased joint laxity but still has a definite end point

- Moderate functional deficit

Grade 3 ligament sprain

Complete disruption of collagen fibres (complete tear)

Symptoms of Grade 3 ligament sprain

- Gross joint laxity without a firm endpoint

- Often immediately painful, but then not due to disruption of nociceptors.

- Can be considerable swelling which may occur rapidly due to haemarthrosis.

- Significant functional deficit

Acromioclavicular joint (AC joint) is a common injuries for athlete who do what?

Fall onto the point of there shoulder

Type 1 AC joints injury

Refers to a sprain of the caspule of the joint

Type 1 AC joint injury charcteristics

- Localised tenderness

- pain on movement especially horizontal flexion

Type 2 AC joint injury

complete tear of the AC ligament, with a sprain to the coracoclavicular ligaments

Type 2 AC joint injury characteristics

- localised tenderness

- on examination small palpable step deformity

Type 3 AC joint injury

Consist of a complete tear of the coracoclaviculr ligaments, including the conoid and trapeziod portions, and the AC ligament.

Type 3 AC joint characteristics

- marked step deformity

-25-50% greater coraclavicular distance than the uninjured side

Type 4 AC joint injury

complete tears of the coraclacicular ligaments ad the AC ligament.

Type 4 charcteristics

- posterior displacement of the clavicle

Type 5 AC joint injury

complete tears of coracoclavicular ligaments and AC ligaments

Type 5 charcteristics

- marked step deformity

- Has typically between 3-5 times greater coracoclavicular space than normal.

Type 6 AC joint injury

complete tear of coracoclavicular and, and AC ligaments

Type 6 charcteristics

- Inferiorly displaced clavicle into either the subacromial or subcoracoid position.

Which type of AC joint injuries are rarer?

Type 4,5 and 6 due to the complete ruptures of all ligament complexes.

what does "hyper mobility" assessed by multi-joint "laxity" predispose you to?

Subluxation and dislocation injuries.

Joint stability depends on what?

the interactions between passive active and neural subsystems.

Dislocation

complete dissociation of the articulating joint surfaces.

Subluxation

articulation surfaces remain partially in contact (partial dislocation)

What is a common injury in high ankle sprains?

Tibio-fibular diastasis

What does a tibio-fibular injury entail?

distal separation of the tibia and fibula due to a tear/rupture of the tibiofibular syndesmosis.

Unstable joints/structures are more likely to dislocate, these joints include:

- shoulder (anterior)

- acromioclavicular joint

- finger (PIP joints)

- patella (lateral)

Stable joints, very dislocate but when the do it is extremely painful. Some of these stable joints include

- Hip

- elbow

Distraction force

a force applied to a body part to separate bony fragements or joint surfaces.

Luxation/luxity predisposes you to what?

impingement

When does acute meniscal tears occur?

the shear stress generate within the knee inflexion and compression combined with femoral rotation exceed the meniscal collagen's ability to resist these forces.

What meniscus is at a greater risk and why?

Medial, due to its attachment to the medical joint capsule, thus decreasing its mobility, compared to the lateral meniscus.

The signs of a mensical tear include:

-joint line tenderness

- joint effusion

- pain usually present with knee hyperflexion

- restricted ROM

- positive mcmurrays test

- popping or clicking within the joint

there are six types of meniscal tears

- longitudinal : tear in middle posterior horn

- degenerative : breakdown of fibres in posterior horn

- flap : cut in the posterior horn

- radial : tear near the anterior horn

- bucket handle : large hole in middle

- horizontal cleavage: cross section has left the middle.

Joint effision

There is increased intra-articular fluid. It usually occurs after a traumatic bone, or meniscal injuries.

Joint effusion can occur by what fluids

Increased synovial fluid or you have bloody effusion an is also known as hemarthrosis.

What causes acute articular cartilage injuries

Acute joint subluxation or dislocation and acute ligaments sprains or ruptures can lead to locally high compressive forces and the superimposition of shearing forces due to excessive translation.

what are the two types of acute cartilage injuries

- chondral : cartilage

- osteochondral : cartilage and underlying subchondral bone

Are chondral and ostechrondral injuries common

Due to better detection methods (MRI) chondral and osteochrondral injuries are far more common than previously realised.

Typical changes on an x-ray that can be due to chondral injuries are:

- joint space narrowing

- subchondral sclerosis

- subchondral cyst formation

- ostephytes

Why are chondral an osetchondral injuries a concern?

Due to there poor healing (articular cartilage has poor regeneration capacity due to it being avsucular) and their contribution to the development of premature osteoarthritis.

Muscle strain account for how many sport-related injury at the elite level

Approx 50% (half)

What muscle do muscle strain most commonly occur in?

- hamstring

- quadriceps

-gastrocnemius

why do muscle strains most commonly occur in the hamstrings, quadriceps and gastrocnemius muscles?

These muscle are exposed to the highest amount of total tensions. They also often contract eccentrically and they contain a high proportion of type 2 (fast twitch) muscles fibres.

The classic model of muscle strain classification looks at tears of the muscles at the what?

Muscle tendon junction tendinous interfaces.

Grade 1 classic muscle strain classification

Minor sprain

- small number of fibres ruptured

- pain localised

- no strength loss

Grade 2 classic muscle strain classification

- large number of fibres ruptured

- reduced strength

- swelling and pain limited movement

Grade 3 classic muscle strain classification

Severe sprain

- complete tear of the muscle and muscle-tendon junction

- significant strength loss

- obvious visual defect

The evolving muscle strain classification model

1. small injuries (tears)

2. Moderate injuries (tears)

3. extensive tears

4. complete tears

- myofascial

- within the muscle at the MTJ

- extends into tendon

Why does a muscle strain that also involves damage to the intramuscular or central tendionous structure have the potential to delay healing and return to play

Tendinoius structures are metabolically slower and therefore have a slower healing rate

A bicep femoris strain hat involves the central tendon disruption vs bicep femoris str5ain without central tendon disruption recovery rate.

72 days vs 21 days

Are biarticular muscles pre-disposed to strains

Yes

What are some factors in muscle strains.

- agoinist-antagonist imbalance (quad-ham ratio)

- muscle tendon interfaces (semitenindous)

- elasticity

Are type 1 or type 2 hamstring sprains more common

Type 1

Type 1 hamstring muscle sprain

Involves the long head of the biceps femoris, most commonly occurring at the proximal tendon junction.

Occurs during high speed running

Type 2 hamstring muscles sprains

Sprain is located close o the ishial tuberosity and involves the proximal free tendon of the semimembranosus

Occurs during ,movements leading to extensive stretching of the tendon at a slow speed.

Which hamstring strain causes a more market acute decline in function

Type 1

Which hamstring strain requires a longer rehabilitation period

Type 2

Haematoma

solid swelling of clotted blood wihtin the tissues

Intramuscular haematoma

Collection of blood within a muscle. Result of direct trauma or muscle tears. More painful and restrictive than inter-muscular haematoma

Inter-muscular haematoma

Internal bleeding between muscle fascia and interstitial spaces. Cause more persistent swelling and bruising than intramuscular, therefore generally more evident

Muscle contusions

Muscle 'corks' refers to bleeding and subsequent haematoma formation within a muscle and its surround connective tissues sheaths.

What causes muscle contusions

Occur when a muscle is compressed against the underlying bone by a blunt, external force

Most common (superficial) sites for contusions are?

- vastus lateralis

- biceps brachii

Other (medial) sites for contusions are?

-thigh adductors

- medial gastrocnemius

Myostis ossificans

Is a form of heterotrophic ossification and refer to the formation of bone within a muscle.

Local factors that can cause myositis ossification

-Reserve of Ca++ in adjacent skeletal tissues

- vascular stasi tissue hypoxia

-mesenchymal cells with osteblastic activity

How long does it take for myostis ossificantion to occur

2-4 wks after injury at which time the area of calcification may be visible on an x-ray

Partial tendon rupture

- Grade 1/2 equivalent ligament sprain

- small to large number of rupture fibres

- pain and limited function

Complete tendon rupture

- Grade 3 equivalent ligament sparin

- total rupture of tendon

- acute pain and no-function of specific muscle tendon unit.

what test allows you to determine fi there is an achilles tendon rupture?

Thompson test

Two common types of avulsion fractures typically seen in sports medicine

- mallet finger (extensor mechanism)

- jersey finger (flexor digit profundus)

Possible issue/complication with fractures are

- nerve damage

- vessel damage

-bleeding/shock

- infection

Colles Fracture

fracture of the distal radius with dorsal (posterior) and radial displacement of the distal fracture segment

Greenstick fracture

- incomplete break

- generally occurs in younger athletes due to low mineralisation

Bone brusing involves

- Microtrabecular fractures

-haemorrhage

- odema

Bone bruising is generally evident from

12-14 wks

Subchondral bone bruise

bleeding between the cartilage and bone beneath, causing the cartilage to separate form the bone.

Interosse bone bruise

bleeding inside the bone marrow

Subperiosteal hematoma

bleeding beneath the periosteum

Periosteal contusion

bleeding occurs under the periosteum usually a result of a direct blow to the bone (usually tibia)

what is the percentage of all fractures in children that involve the growth plate

15% more than a third of these occur in organised sports.

Type 1 growth plate injuries

epiphysis is completed separated form metaphysis

Type 2 growth plate injuries

epiphysis and growth plate is separate from metaphysis

Type 3 growth plate injuries

Fx thru the epiphysus seperate part of the apiphysis and growth plate form metaphysis

Type 4 growth plate injuries

Fx thru epiphysis, across growth plate and into metaphysis

Type v growth plate injuries

Growth plate is crushed

which type of growth plate injuries generally heal well

Type 1 and 2

What is prognosis of type 5 growth plate injuries

Poor it can also lead to growth zone lesions

What can occur if type 3 and 4 growth plate fractures are not recognised

Produce permanent injury to growth plate, resulting in growth disturbances