Injuries To Bones And Joints Of The Upper Limb Flashcards
How is bone repaired?
- Haematoma at break
- Formation of fibrocartilaginous callus
- Formation of bony callus
- Remodelling where bone is resorbed and addition of compact bone (stress line will appear)
What indicates that a bone after a break has been healing, is now sufficiently solid?
Present of a reformed marrow cavity
When will a bone malunite?
When the tensile forces are going away from eachother but the compressive forces are going towards eachother
What 2 things are needed for a bone to repair?
- Fracture stability (internally/externally fixated)
2. Vascularity
What 2 joints are formed by the clavicle?
- Sterno-clavicular
2. Acromio-clavicular
What is special about the clavicle?
Only horizontal long bone in the body
What is the function of the clavicle?
Keeps shoulder at set distance from manubrium in an arc around the centre of the body
How is the clavicle fractures?
Force in the coronal plane in a lateral to medial direction along the line of the bone e.g. by a FOOSH or a direct fall onto shoulder laterally
How can the sterno-clavicular joint dislocate?
Anteriorly (more common)
Posteriorly
What are the complications of a posterior dislocation of the sterno-clavicular joint?
Arteries and veins can be occluded or punctured cutting off blood supply
Trachea can get punctured or transected altogether
What can happen to the acromio-clavicular joint?
Injury
Dislocation
What age group tend to fracture their clavicle?
Children and often they wont complain much about it, someone will just notice a worrying lump on their shoulder!
What is the problem with clavicle fractures?
Its difficult to immobilise the clavicle
Its a different type of bone so heals differently to typical bones
What external fixation can be used for the clavicle?
Figure 8 brace (pretty useless)
1 arm sling around neck
What additional structures can be damaged with clavicle fractures that occur by a superior force?
Brachial plexus
Subclavian vein
May need to surgically repair these injuries
What must you do quickly after a patient has sustained an intra-articular fracture?
Repair the fracture surface as the patient will develop OA quickly otherwise
What are the main areas injuries of the scapula?
- Blade fracture
- Spine fracture
- Glenoid fossa e.g. intra-articular joint fracture
- Spinous process fracture
What ways can the shoulder dislocate in order from most to least common?
Anterior
Inferior
Posterior
What is a mechanism by which a person can attain a posterior shoulder dislocation?
Electric shock or epileptic fit where shoulders can extend backwards excessively
What symptoms will a patient get if they damage the axillary circumflex nerve?
LOS/paraesthesia in regimental badge region of upper arm
Patient would not be able to move arm much at all
If a patient has dislocated their shoulder, what must you do before correcting it?
Check for axillary nerve damage by assessing sensation and movement (or tensing of muscles if patient cant move them) otherwise more nerve damage may occur
How can nerves be injured?
Iatrogenic
Hippocratic or Kocher’s correction of a dislocation
When can you correct a dislocation using Kocher’s technique?
When a patients muscles are relaxed straight after a dislocation before they start tensing up
How can someone get axillary vein thrombosis? How do you treat it?
By falling asleep with arm over an arm of a chair where you are sitting and leaning on the vein - must give anticoagulants
What parts of the proximal humerus can be fractured?
Head
Greater tuberosity
Anatomical neck
Surgical neck
What nerve is at risk of damage by proximal humeral fractures?
Axillary
What are the 4 rotator cuff muscles?
- Subscapularis
- Supraspinatus
- Infraspinatus
- Teres minor
What rotator cuff muscle is most likely to be involved with problems?
Supraspinatus because it can become overused and rub on the acromion, this can lead to calcification and also eventually lead to tendon rupture
What is the characteristic sign of a supraspinatus rotator cuff injury?
The patient would be unable to initiate abduction
Passive abduction is possible but there will be pain after 45 degrees where the humeral head is trapping the tendon
How can you diagnose a rotator cuff muscle injury?
US
MRI
How do you manage a rotator cuff muscle injury?
Inject steroid into tendon in shoulder directly
Surgery
What nerve can be damaged by humeral shaft diaphysis fractures?
Radial n. in the spiral groove so extensor muscles will be lost
How can you fracture your diaphysis humeral shaft?
Direct blow
Arm wrestling
What clinical sign will show if the extensor muscles are damaged?
Wrist drop as dorsiflexion of wrist is not possible
Numbness in 1st dorsal web space at base of thumb
How do manage a humeral diaphysis shaft fracture?
U-slab
Internal fixation with metal or nails
What age group commonly fracture their supracondylar aspect of the humerus?
Children commonly by a FOOSH or fall onto the elbow
What is a fracture blister?
A swollen blistered skin lesion that looks similar to a burn occurring after fracture in that area
What neurovasculature can be damaged with a supracondylar humeral fracture?/
Brachial artery
Median nerve
Anterior interosseous nerve
What will the patient not be able to do if they damage their anterior interosseous nerve?
Index finger flexion
What are the signs of compartment syndrome?
5 P's: Pallor Pule Paraesthesia Paralysis Pain (INCREASING DESPITE ANALGESIA)
Why must you relieve compartment syndrome?
Neurovasculature becomes squashed
What is an after effect of not treating compartment syndrome?
Volkmann’s ischaemic contracture - muscles die and shrink, wrist bends and fingers are drawn into a claw
What nerve might you damage if you dislocate your elbow?
Ulna nerve
What would a patient not be able to do if their ulna nerve is damaged?
Flexion of ring and little finger
What type of fracture is caused in the elbow by a triceps tendon avulsion injury?
Olecranon fracture
What position do you want to keep your elbow in if you fracture the olecranon?
Bent as the fracture becomes tighter with bending
What is a pulled elbow?
Where the head of the radius is pulled out of its socket usually due occurring in children as their head of radius is not fully formed till 3 and the surrounding annular ligaments are flexible when parents swing children by their arms
How do you manage a pulled elbow?
Straighten elbow, put thumb on head of radius and pop it back in
What is a forearm monteggia fracture?
Anterior dislocation of the head of the radius only usually occurring if the ulna is bent or fractures as it is shorter than the radius allowing the radius to pop out
What is another fracture common in children?
Greenstick fracture of the wrist as bones are quite soft allowing the bone to buckle and crack on inside - not really painful at all
How would you manage a greenstick fracture of wrist?
Plaster backslab
What is Colles’ fracture? What is at risk of damage?
Dorsal displacement of the wrist at the distal radius
What nerve is at risk when a Colles’ fracture is sustained?
Median
How would you manage a Colles’ fracture?
Metal work potentially
What is the risk of a scaphoid fracture?
Avascular necrosis
OA if not fixed
How are scaphoid fractures sustained?
Commonly in younger people due to sports injuries or FOOSH where there is excess DORSIFLEXION of the wrist
What clinical sign should you go off the basis of with a scaphoid fracture?
Tenderness in anatomical snuffbox as fractures can be so thin X-rays cannot pick them up
What is a Bennett’s fracture?
Fracture at base of thumb due to pulling thumb backwards or forwards e.g. skiing accidents where thumb is around outside of pole and gets ripped off
How can you manage a Bennett’s fracture?
Internal fixation with metal
What is mallet finger?
Forceable flexion of DIP joint e.g. when you have stubbed your finger, tearing the extensor tendon from its attachment so the DIP joint is consistently flexed
What do you want to be affected with mallet finger? Why?
Bone also as then it will heel as a fracture but often its just the tendon affected which does not heal as easily
How do you manage mallet finger?
By putting finger in a cast so it is extended and can heal better
