- break in the surface of the bone

Fracture

- complete and persistent displacement of a joint where at least part of the supporting joint capsule and ligaments are disrupted

- loss of contact between articular surfaces

Dislocation

- partial dislocation of a joint, where bones are partially separated from one another, and articular surfaces are no longer congruent

- pts may still be able to move joint

Subluxation

- temporary subluxation of a joint, where articular surfaces return to normal alignment

- capsule and ligaments are often severely damaged and sometimes completely torn

- no deformity other than swelling

Sprain

- fracture where overlying skin remains intact

- periosteal blood vessels and surround soft tissue vessels are torn

- hematoma occurs, compression of surrounding soft tissue limits expansion

- may result in up to 1 L of blood loss in thigh

Closed Fracture

- fracture where skin overlying fracture has been broken

- complicated by decreased rate of healin, increased risk of infection, greater blood loss

Open Fracture

- shaft of long bone

Diaphyseal bone

- flared portion of the bone at the ends of the shaft

Metaphyseal bone

- involving both ends of the bones, forming part of the adjacent joint

- fractures here may affect growth of bone in later life

Epiphyseal bone

- fracture here may result in post-traumatic arthritis

Intra-articular bone

- difficult to diagnose because there is no associated deformity other than swelling

- must cause pain, swelling, bruising, and point tenderness to palpation

- should be evaluated by x-ray to rule out

Non-displaced fractures

- described by the type of deformity it produces

- angular, rotational, shortening

- several types frequently occur in the same fracture

- usually described in cm or as a percentage of the bone diameter

Displaced fracture

- fracture with angulation in the frontal plane (varus/inward or valgus/outward) or in the sagittal plane (anterior or posterior)

Angular fracture

- after fracture, pull of gravity or muscle spasm rotates the distal fragment along the long axis of the bone resulting in either internal or external rotation

Rotational fracture

- after fracture, surrounding muscles spasm causing the bones to overlap

- when distal fragment of bone overlaps proximal fragment (bayoneted fracture)

Shortening Fracture

- fracture that is perpendicular to shaft of bone

Transverse fracture

- multiplanar and complex fracture line

Spiral fracture

- more than two fracture fragments

Comminuted fracture

- comminuted fracture with three large fragments in the shaft of a long bone

Segmental fracture

- fracture line crosses the articular cartilage and enters the joint

Intra-articular fracture

- results from a muscle pull that tears the musculotendinous insertion on the bone from the remaining mass of bone

Avulsion fracture

- due to crushing injury, particularly common in cancellous flat bones (vertebrae)

- typical in pts with osteoporosis

Compression fractures

- when bone is weakened by tumor or other dx such as osteoporosis

Pathologic fractures

- unique to children

- fracture is in the shaft of the bone

- cortex on the convex side of the deformity is broken, while cortex on the concave side remains intact

Greenstick fracture

- occurs in the metaphysis of long bones in response to excessive compressive loading

- unique to children

- most often seen in the distal radius from a fall on an outstretched hand

Buckle fracture

- nerve lies in spiral groove on the humeral shaft

- fracture or over aggressive manipulation may damage this nerve

- wrist drop will result

Radial Nerve Palsy

- may result in supracondylar fracture of the humerus

- anterior displacement of the humeral shaft fragment that impinges on the radial nerve, median nerve and brachial artery

Hyperextension injury of the elbow

- results in damage to the sciatic nerve anywhere from 5-15% of the time

- foot drop will result

- immediate reduction is the best treatment

- common in car accidents (dashboard injury)

Posterior dislocation of the hip

- accumulation of fluid at high pressure within closed muscle compartment decreases perfusion beyond muscle viability point

- muscle and nerves become ischemic, necrotic

- pain and paralysis result

- diagnostic clues are severe pain with stretching, loss of sensory function distally (par-, hyper-, hypo-, an-sthesias), decreased capillary filling

- may result from casting

- most common sites are leg and forearm

Compartment Syndrome

- respiratory failure often develops within the first 72 hours after a long bone fracture

- fever, tachycardia, tachypnea, mental confusion, petechiae in the axillae

- thought to be connected with FFA release into bloodstream from fracture site

Adult Respiratory Distress Syndrome (ARDS)

- cellulitis, abscess, myonecrosis (clostridial infection), osteomyelitis

- open fracture has greater risk than closed

Infection

- fracture heals with a residual deformity

- angulation, rotation, shortening

Malunion

- occurs when the fracture gap fills with scar tissue rather than bridging callus

- results when it takes longer than normal for bridging callus to form

Nonunion and Delayed Union

- these fractures can cause deformity with growth

- Salter Harris fractures affect epiphyseal plates

Epiphyseal fractures

- seen most often in malunion and intra-articular fractures

- can occur within a few months or 15-20 yrs after fracture

Post traumatic arthritis

- occurs when blood supply to bone is interrupted

- most often seen in femoral neck fractures

- can occur without fracture in children (Legg-Calve-Perthes syndrome)

- slipped capital femoral epiphysis also leads to this in obese children

Avascular necrosis

- occur when pts fall on their outstretched hand

- have the potential to interrupt blood supply from the proximal segment of the bone because blood is supplied to the distal scaphoid only

- avascular necrosis is a common complication

Scaphoid fractures