Orthopaedics lecture notes

Ortho – fractures

2 factors that lead to fracture, energy of the event and the strength of the bone.  Energy can be low chronic leading to stress fractures, or acute high-energy. Bone strength is either normal or diminished from demineralisation or pathology.  X rays should show joint above and below the fracture.

On Examination:

  • Pain and tenderness

  • Deformity and swelling – haematoma, haemarthrosis.  If deformity causes skin tenting then this will need to be reduced before XR for avoid skin necrosis. (Think of a fracture as a soft tissue injury with a break in the bone)

  • Locally warm

  • Abnormal mobility and crepitus

  • Loss of function

  • Always check distal neurovascular status.

Definitions:

  • Fracture = break in the continuity of a bone

  • Comminuted fracture = >2 fragments

  • Gross comminution = multiple fragments, often following severe high energy trauma, union often delayed or difficult.

  • Types of #:

  • Transvere – across bone

  • Oblique – cut in an oblique down the bone, like fancy cucumber

  • Spiral – spirals, result of a twisting motion

  • Greenstick – in children, part of bone appears to buckle, other side may have a fracture

  • Crush –

  • Burst –

  • Avulsion – soft tissue insertion into bone is ripped away pulling part of the bone with it.

  • #dislocation / subluxation – dislocation or subluxation associate with a fracture.

  • Open / compound – some communication with the external world with a much higher risk of infection.  Gustilo-Anderson classification:

    • Type I = wound <1cm, clean wound

    • Type II = wound 1 - 10cm, clean wound

    • Type IIIA = wound >10cm, high energy but adequate soft tissue coverage

    • Type IIIB = would >10cm, high energy but with inadequate soft tissue coverage (plastic input)

    • Type IIIC = all injuries with vascular injury (vascular input)

  • Complicated – important soft tissue damage present, eg fracture opening body cavities or inner organs like the brain, lungs, viscera, spinal cord, concurrent neurovascular injury.

  • Simple – no soft tissue injury

  • Impacted – bone fragments forced together (usually stable)

  • Unstable – displaced or have potential to displace, very relevant when important soft tissue structures at risk eg spinal column

  • Hangman’s fracture – fracture of bilateral pedicle / lamina of the second cervical vertebra leading to immediate death due to damage to the spinal cord.

Investigation:

  • XR – at least 2 views, often more for relevant injuries suspected

  • / MRI / CT

  • DEXA (Dual Energy X-ray Absorbed) scan for bone density in low energy injuries.

Classification of fractures:

  • Anatomical location:

    • Epiphysis, diaphysis, metaphysis, intraarticular

    • Proximal, middle, distal

    • Head, neck, trochanter, shaft, supracondylar, condylar

  • Degree:

    • Complete

    • Incomplete (children eg hairline, buckle, greenstick etc)

  • Configuration:

    • Transverse

    • Oblique

    • Spiral

    • Longitudinal

  • Number of fragments:

    • Simple (linear)

    • Comminuted

    • Segmental

  • Open / closed

  • Stability

  • Displacement (needs reduction)

    • Shortening,

    • Rotation

    • Sideways shift or tilt

  • Dislocation – loss of joint integrity

  • Subluxation – partial loss of joint surface integrity

Salter Harris Classification for epiphysial fractures:

  • I –    S = Straight across (through the growth plate, physis)

  • II –   A = Above (fracture divert into main shaft of bone, metaphysis) *most common

  • III –  L = Lower or BeLow (fracture diverts into growth plate, epiphysis)

  • IV – T = Through or TWO (goes through both the epiphysis and metaphysis)

  • V – ER = Everything Rammed (epiphysis crushed into the metaphysis, loss of physis)

Fracture healing:

  • Goals:

    • Restore optimal functional state

    • Prevent bony and soft tissue complications

    • Prevent malunion, while preventing soft tissue wasting and contractures

  • Immediate:

    • Bleeding and fracture haematoma forms

    • Inflammation

  • 2-3 days

    • Phagocytosis.  Capillary budding, granulation tissue

    • Osteogenic cells invade and lay down osteoid.

  • 3 weeks

    • Soft callus – cartilage and osteoid

  • 6-12 weeks

    • Hard callus

  • 3-4 months

    • Clinical union

  • 6-12 months

    • Remodelling

 

Potential ortho emergencies:

  • Amputations

  • Open fractures

  • Penetrating injury / pelvic fracture / massive haemorrhage / vascular injury (>6h results in irreversible damage).

  • Dislocated hip / knee

  • Compartment syndrome

  • Complex trauma

  • Spinal injury or progressive neurology.

 

Management open #

  • In ED = Examine wound 1X, sterile dressing, reduce to restore limb alignment, tetanus and antibiotics

  • In OR = Debride to remove foreign material, dead tissue and any bacteria, clean thoroughly and irrigate.  +/- antibiotic beads, stabilize. 

 

Management closed #

  • Reduction if appropriate – either manipulation or open

  • Maintain reduction

    • Intrinsic stability

    • External fixation – splits, POP, cast braces, traction etc

    • Internal fixation – screws, plates, grafts, intramedullary nails, wires and pins

    • Frame fixators – maintain reduction and can extend to bridge a gap

  • Fixation lasts:

    • 12 weeks for long bones, get cancellous ends of long bones and in short bones in 6-8 weeks)

    • Children and elderly, or for pain relief only 2-3 weeks

 

Complications of fractures:

  • Soft tissue injuries:

    • Skin – open #, degloving injuries, and ischaemic necrosis.

    • Muscles – crush and compartment

    • Blood vessels – vasospasms and arterial laceration

    • Nerves:

      • Neuropraxia – mild crush injury (sat night radial nerve injury)

      • Axonotmesis – nerve damaged but axon sheath intact – nerve can regrow.

      • Neuromesis – complex nerve damage.

    • Ligaments – joint instability and dislocation

  • Compartment Syndrome – Not only when fractures

    • 5P’s - Pain (out of proportion to injury or clinical situation), Pallor, Paraesthesia, pulselessness, paralysis

    • Fasciotomy when:

      • Worsening clinical state

      • Tissue pressure rising from 30mmHg below diastolic, as it approaches 20mmHg below diastolic.

      • Significant tissue injury

      • History of 6 hours total ischaemia when perfusion restored.

  • Complications at time of injury:

    • Haemorrhage, damaged to important structures and skin loss

  • Complications medium term:

    • Local:

      • Tissue necrosis,

      • Infection,

      • Loss of alignment

    • General:

      • DVT, PE, fat embolism

      • Pneumonia

  • Late complications:

    • Delayed and non union, malunion

    • Late wound infection

    • Joint stiffness and contracture

    • Sudeks atrophy - ?sympathetic malfunction

    • OA

    • Chest infections, bed sores, UTI

    • AVN

    • Tendon contracture, nerve compression,

    • Volkmann contracture (necrosis of muscles in forearm following # in children causes arm to contract in.