Week 5 Flashcards
what is arthroplasty also known as
joint replacement
what is replacing one half of the joint known as
hemiarthroplasty
when can excision of a joint be useful
in smaller joints
e.g. CMC jt
what is arthrodesis and when is it used
surgical stiffening or fusion of a
joint in a position of function
used for end stage ankle arthritis, wrist arthritis and arthritis of the first MTP jt of the foot (hallux rigidus)
what is osteotomy and when is it used
surgical realignment of a bone
used for deformity correction or to redistribute load across an arthritic joint
what type of soft tissues would benefit from decompression
supraspinatus tendonitis
subacromial decompression
what can be performed in the extensor tendons of the wrist in RA to prevent rupture
synovectomy
Mx of joint instability
physio - strengthen surrounding muscles
splints
Surgery
- ligament tightening/advancement (e.g. ankle instability)
- ligament reconstruction using tendon graft (e.g. ACL reconstruction)
- soft tissue reattachment (e.g. shoulder instability)
conditions that cause significant ligamentous laxity
Ehlers-Danlos
why would spinal instability need to be fused
may cause pain, nerve root compression or spinal cord compression
what is osteomyelitis
infection of bone
pathogenesis of osteomyelitis
- bone infected
- enzymes from leucocytes cause local osteolysis
- pus forms which impairs blood flow
- infection difficult to eradicate
what is sequestrum
dead fragment of bone which has broken off
with the presence of sequestrum, osteomyelitis can be cured by antibiotics - true or false
false
antibiotics will not cure the infection alone
what is involucrum
new bone forming around the area of necrosis
who gets acute osteomyelitis
children + immunocompromised
in absence of recent surgery
chronic osteomyelitis
evelops from an untreated acute osteomyelitis and may be associated with a sequestrum and/or involucrum
where does the infection tend to be in chronic osteomyelitis in adults
axial skeleton (spine or pelvis) with haematogenous spread from pulmonary or urinary infections, or from infection of the intervertebral disc (discitis)
what can suppress chronic OM and what can this cause
antibiotics
lay dormant for many years before reactivating causing localized pain, inflammation, systemic upset and possible sinus formation
what disease can cause chronic OM
TB
particularly in the spine through haematogenous spread from primary lung infection
what organisms cause OM in newborn
s.aureus
enterobacter sp
group A & B strep
what organisms cause OM in children (up to 4y/o)
s.aureus
group A strep
H.influenzae
Enterobacter sp
what organisms cause OM in children/adolescents)
s.aureus
group A strep
H.influenzae
Enterobacter sp
what organisms cause OM in adults
S. aureus
occasionally enterobacter or streptococcus sp
what organisms cause OM in sickle cell anaemia patients
s. aureus
salmonella
acute OM Tx
best guess antibiotic IV
surgical drainage of pus
remove infected bone
washout area
chronic OM Tx
antibiotics IV Surgery - debridement - to gain deep bone tissue cultures, - remove any sequestrum - excise any infected or non‐ viable bone
what happens if the bone becomes unstable after removing infected bone in OM
internal or external fixation
adv of external over internal fixation in treatment of chronic
bone can be subsequently lengthened if it has been shortened as a result of the debridement
who is at risk of OM of the spine
Poorly controlled diabetics
intravenous drug abusers
immunocompromised patients
Sx of OM of the spine
insidious onset of back pain which is constant and unremitting.
paraspinal muscle spasm
spinal tenderness
fever and/or systemic upset. neurologic deficit
paravertebral or epidural abscess
Ix for OM of the spine
MRI
Blood cultures
Tx for OM of the spine
high dose IV antibiotics
CT guided biopsy to obtain tissue culture
Indications for surgery of OM of the spine and the surgery
inability to obtain cultures by needle biopsy,
no response to antibiotic therapy progressive vertebral collapse progressive neurological deficit.
surgery
- debridement,
- stabilisation
- fusion of vertebrae
what is the concern when a deep infection complicates a prosthetic joint replacement
development of chronic infection with pain, poor function, recurrent sepsis, chronic discharging sinus formation and implant loosening
what is there a risk of with deep infections
chronic OM
non-union fracture
what is primary bone healing
1st intention healing
minimal fracture gap (less than 1mm). Bone bridges the gap with new bone from osteoblasts. Occurs for healing of hairline fracture and when # are fixed with compression screws and plates
what is secondary bone healing
2nd intention - used in majority of fractures
Gap at # needs filed temporarily to act as a scaffold for new bone. Involved inflammatory response.
fracture process of secondary bone healing
Fracture occurs
Haematoma occurs with inflammation from damaged tissues
Macrophages and osteoclasts remove debris and resorb the bone ends
Granulation tissue forms from fibroblasts and new blood vessels
Chondroblasts form cartilage (soft callus)
Osteoblasts lay down bone matrix (collagen type 1)– Enchondral ossification
Calcium mineralisation produces immature woven bone (hard callus)
Remodelling occurs with organization along lines of stress into lamellar bone
when does soft and hard callus formed
soft - 2nd to 3rd week
hard - 6-12 weeks
what is required for secondary healing
good blood supply for oxygen, nutrients and stem cells and also requires a little movement or stress
what can causes atrophic non union
Lack of blood supply, no movement (internal fixation with fracture gap), too big a fracture gap or tissue trapped in the fracture
what can impair healing of fracture
smoking
vascular disease
chronic ill health
malnutrition
what type of fractures have greater risk of stiffness, pain or OA
intra-articular
Ix of #
AP and lateral X-ray
Bone scans for stress fractures
MRI - when clinical suspicion but normal X-ray
CT - assess + determine degree of damage (e.g. polytrauma)
initial Mx of long bone fracture
Analgesia e.g. IV morphine
Splintage/immobilisation
Ix
what splint is used in femoral shaft fractures
Thomas splint
Tx for stable, undisplaced, minimally displaced and minimally angulated fractures
non-operatively
period of splint age or immobilisation
rehab
Tx for Displaced or angulated fractures where the position is deemed unacceptable
reduction under anaesthetic
Closed reduction and cast application
Tx for unstable injuries
surgical stabilisation
small percutaneous pins (K‐wires) for small fragments, cerclage wires, screws, plates & screws, intramedullary nails or external fixation.
Tx for Unstable extra‐articular diaphyseal fractures
Open reduction and Internal Fixation (ORIF) using plates and screws
goal - anatomic reduction and rigid fixation leading to primary bone healing
when might ORIF be avoided
soft tissues too swollen
blood supply to the fracture site is tenuous (high energy),
ORIF may cause extensive blood loss (eg femoral shaft)
if ORIF cannot be used what can be done
closed reduction and indirect internal fixation with an intramedullary nail with dissection distant to the fracture site
Tx for intra-articular fractures
ORIF using wires, screws and plates
Poor outcome predicted then Joint replacement or arthrodesis
why are elderly more likely to be treated non-operatively
co-morbities
osteoporosis
dementia
lower functional demand
signs of compartment syndrome
1 - increased pain on passive stretching of the involved muscle
2 -severe pain outwith the anticipated severity in the clinical context
3 - limb very swollen and tender to touch
what artery is at risk with knee dislocations
popliteal artery
what is at risk in paediatric supracondylar fracture of the elbow
brachial artery
what artery is at risk with shoulder trauma
axillary artery
Signs/Symptoms of non-union
ongoing pain and oedema
movement at fracture site
what fractures have delayed union
tibia fracture - slowest healing fracture, 16 weeks
femoral shaft fracture - 3-4 months
what causes hypertrophic and atrophic non-union
hypertrophic - instability and excessive motion
atrophic - rigid fixation with a fracture gap, lack of blood supply to the fracture site, chronic disease or soft tissue interposition.
what fractures are prone to poor healing
scaphoid wrist fractures
fractures of the distal clavicle
subtrochanteric fractures of femur
Jones fracture of 5th metatarsal
what fractures are prone to AVN
femoral neck
scaphoid
talus
Initial management of open fractures
IV broad spectrum antibiotics
what are the 3 grades of ligament ruptures
grade 1 - sprain
grade 2 - partial tear
grade 3 - complete tear
Mx of soft tissues injuries
RICE
