Cortex- Elective surgery Flashcards
what are the surgical strategies for the management of an arthritic joint
arthroplasty/ joint replacement
excision or rescection arthroplasty
arthrodesis
osteotomy
what is hemiarthroplasty
replacing one half of a joint
what joints can be replaced
hip, knee, shoulder, elbow, ankle, 1st MTP joint of the great toe, MCP joints of the hand and wrist
what can joint replacements be made of
stainless steel, cobalt chrome, titanium alloy, polyethylene, ceramic
in hip replacements what materials can be coupled
metal polethylene
ceramic polyethylene
ceramic ceramic
metal metal
what ultimately will happen to a hip replacement
fail due to loosening or breakdown of the joint replacement components
what can cause a hip replacement to fail
wear particles producing an inflammatory response or high stresses (loosening)
what is the risk with metal hip replacements
metal particles can cause an inflammatory granuloma (pseudotumour) which can cause muscle and bone necrosis
what can polyethene particles cause
an inflammatory response in bone with subsequent bone resorption (osteolysis) resulting in lossening
what is the risk with ceramics
can shatter with fatigue due to their brittleness
what are the problems with revision surgeries
more difficult
complication rates higher
functional outcomes are poorer
patient satisfaction less
why do younger patients have an increased risk of revision surgery
as there is higher demand on the joint replacement
what are the serious complications of joint replacement
deep infection, recurrent dislocation, neurovascular injury, pulmonary embolism, medical complications (renal failure, MI, chest infections ect)
what needs to be done if a fulminant infection is diagnosed early after a joint replacement
surgical washout, debridement, prolonged parenteral antibiotic therapy
why are infections that last longer than 3 weeks harder to salvage in a joint replacement
as infecting bacteria adhere to the foreign surface and grows a biofilm which resists the immune response
what is usually required if there is a deep joint replacement infection for more than 3 weeks
removal of implants
left for 6 weeks
given parenteral antibiotics
revision joint replacement once cleared (soft tissues lose elasticity and scar- joint stiffens)
what are the early local complications of a joint replacement
Infection, dislocation, instability, fracture, leg length discrepancy, nerve injury, bleeding, arterial injury / ischaemia, bleeding, DVT
what are the early general complications of joint replacements
Hypovolaemia, shock, acute renal failure, MI, ARDS, PE, chest infection, urine infection. There is approximately a 0.2% chance of dying as a result of a hip or knee replacement.
what are the late local complications of a joint replacement
Infection (from haematogenous spread), loosening, fracture, implant breakage, pseudotumour formation.
what does excision involve and when is it used
removal of bone and cartilage of one or both sides of a joint
good for small joints e.g. kellers procedure for hallux valgus
what is arthrodesis
surgical stiffening or fusion of a joint in a position of function
remaining hyaline cartilage of the joint and subchondral bone is removed and the joint is stabilised causing bony union and fusion
when is arthrodesis good
to relieve pain
end stage ankle arthritis
wrist arthritis
arthritis of the first MTP joint of the foot (hallux rigidus)
what are the negatives of arthrodesis
function may be limited particularly in large joints may increase pressure in surrounding joints causing arthritic change
what is an osteotomy
surgical re alignment of a bone which can be used to correct deformities or redistribute load across an arthritic joint (shift to an undiseased part)
what tendons can be injected with steroid around the tendon due to risk of rupture
achilles, extensor mechanism of knee
what might refractory soft tissue inflammatory problems benefit from
surgical debridement or decompression (supraspinatus tendonitis and subacromial decompression)
when can synovectomy be performed
for the extensor tendons of the wrist on RA or for inflammation of the tibialis posterior tendon to prevent rupture
what might major tendon tears require (3) (give examples of the the tendons these are done in)
splintage (achilles), surgical repair (quadriceps, patellar tendon, sometimes achilles), tendon transfer (tibialis posterior, extensor pollicis longus)
how can meniscal tears be surgically treated
with arthroscopic removal (or occasionally repair) if the pain fails to settle or if the cause mechanical symptoms (locking or catching)
how can labral tears of the acetabulum be surgically treated
can be resected or repaired
what is instability
abnormal motion of a joint (rotation or translation) resulting in subluxation or dislocation with pain and/or giving way
where can you get instability
knee (ligament injuries), shoulder, patella, ankle, spine
what can cause instability
injury, ligamentous laxity, anatomincal variation, underlying disease process (RA, knee hyperextension in polio)
how can instability be treated
most- physio, splints, calipers, braces
surgery- soft tissues procedures: ligament tightening (ankle)/ advancement (ankle)/ reconstruction using tendon graft (ACL), soft tissue reattachment (shoulder)
bony: fusion (e.g. in cases of severe laxity (ehlers danlos) soft tissue procedures wont work or in spinal instability), osteotomy (skeletal predisposition to dislocation (e.g. patellar instability))
what symptoms might spinal instability cause
pain, nerve root compression, spinal cord compression
what surgery can help nerve compression
nerve decompression sugery or discectomy (in spinal nerve root compression- disc material or osteophytes causing a radiculopathy)
what can cause joint contractures
neuromuscular disease, spasticity (eg stroke), soft tissue imbalance, arthritis, injury, fibrosing disease (Dupuytren’s), disuse or burns
how can joint contractures be treated
may be passively correctable and may be amenable to splintage, physiotherapy and medications (Baclofen, Botox injections) to relieve spasticity.
Fixed or resistant contractures may require surgical treatment which may consist of tendon lengthening, tendon transfer, release or lengthening of tight soft tissues or bony procedures (osteotomy, arthrodesis).
what soft tissue infections involve orthopaedics in their treatment
infected bursitis, arm/ leg abscesses, wound infections, joint replacement infection
how can organisms infect bone (osteomyelitis)
directly penetrating trauma or surgery
indirectly via haemtogenous spread
what part of the bone is affected in osteomyelitis
can be compact, spongy bone or bone marrow
what is the usually type of organisms causing osteomyelitis
usually bacteria can be fungal
once infected in osteomyelitis, what makes the infection very difficult to eradicate
enzymes from leukocytes cause local osteolysis and pus forms which impairs local blood flow
what is a sequestrum
a dead fragment of bone that can form in osteomyelitis which usually breaks off
what happens when a sequestrian is present
antibiotics alone will not solve the problem
what is an involucrum
new bone that forms around the area of necrosis (sequestrian in osteomyelitis)
what is an additional feature of staph aureus osteomyelitis that makes it difficult to treat
can infect osteocytes intracellularly- harder for immune system to reach
who usually gets acute osteomyelitis in the absence of recent surgery
children - or immunocomprimised adults
why in children can osteomyelitis spread to different parts of the bone
the metaphyses of long bones contain abundant tortuous vessels with sluggish flow which can result in accumulation of bacteria and infection spreads towards the epiphysis
why is there a risk of septic arthritis in neonates and infants with osteomyelitis
certain metaphyses are intra‐articular including the proximal femur, proximal humerus, radial head and ankle and infection can spread into the joint
why is there risk of an abscess expanding in infants with osteomyelitis
infants have loosely applied periosteum and an abscess can extend widely along the subperiosteal space
what is a brodies abcess
form of subacute osteomyelitis in children, with insidious onset. bone reacts by walling off the abscess with a thin rim of sclerotic bone
what is chronic osteomyelitis
develops for an untreated acute osteomyelitis and may be associated with a sequestrum/ involucrum
what are features of chronic osteomyelitis
tends to be in axial skeleton (spine/ pelvis)
haematogenous spread from pulmonary or urinary infections/ discitis
can be peripheral from previous open fracture or internal fixation
what are the symptoms of chronic osteomyelitis
is usually suppressed by antibiotics and can lay dormant for many years
when it reactivates- localised pain, inflammation, systemic upset possible sinus formation
name an infection that can cause chronic osteomyelitis through haemtogenous spread from the lungs
tuberculosis
name organisms that commonly cause osteomyelitis in newborns (<4 months)
S. Aureus, enterobacter sp., group A and B strep
name organisms that commonly cause osteomyelitis in children (4 months to 4 years)
S. aureus, group A strep, H. influenzae, enterobacter sp
name organisms that commonly cause osteomyelitis in adults
S. aureus, enterobacter, streptococcus sp
name organisms that commonly cause osteomyelitis in sickle cell anaemia patients
S. Aureus, salmonella sp
what are the different classifications of osteomyelitis depending on where it affects
superficial- outer surface of bone
medullary
localised- cortex and medullary bone
diffuse- segment affected that causes skeletal instability (e.g. infected non union)
how is acute osteomyelitis treated
by “best guess” antibiotics intravenously unless there is abscess formation which mandates surgical drainage.
If the infection fails to resolve, second line antibiotics may be used or surgery may be performed to gain samples for culture, remove infected bone and washout the infected area.
how is chronic osteomyelitis treated
cannot be cured or eradicated by antibiotics alone. Active infection can be suppressed with antibiotics
Surgery is usually recommended to gain deep bone tissue cultures, to remove any sequestrum and to excise any infected or non‐ viable bone (debridement)
can also do local antibiotic delivery systems and bone grafting
plastic surgery may be needed
what happens if debridement for chronic osteomyelitis causes instability
bone must be stabilized by internal or external fixation
who is at particular risk of osteomyelitis of the spine
Poorly controlled diabetics, intravenous drug abusers and other immunocompromised patients
where is the most common location for spine osteomyelitis
lumbar spine
what is the presentation of spinal osteomyelitis
insidious onset of back pain which is constant and unremitting.
They have paraspinal muscle spasm and spinal tenderness and may have fever and/or systemic upset.
Severe cases may have an associated neurologic deficit
Pus may extrude forming a paravertebral or epidural abscess.
As the vertebral end plates weaken, vertebrae may collapse = kyphosis or vertebra plana (flat vertebra) and disc space may reduce
what investigations should be done in spinal osteomyelitis
MRI- show extent and any abscesses
blood cultures- might show causative organisms
possibly echo- look for endocarditis
what is the treatment for osteomyelitis
high dose IV antibiotics after CT guided biopsy to get culture
(response monitored via CRP)
half patients go on to spontaneous fusion and resolution
surgery (debridement, stabilisation, vertebra fusion) if no response to antibiotics or worsening condition
what role does haematoma play in infection
acts as a growth medium
what are the features of a chronic deep infection of a prosthetic joint
pain, poor function, recurrent sepsis, chronic discharging sinus formation, implant loosening
what is the risk of a deep infection in fracture fixation or stabilisation
chronic osteomyelitis and non union of the fracture
what organisms produce an early prosthetic infection
s aureus, gram negative bacilli (inc coliforms)
what organisms cause low grade prosthetic infection that is often diagnosed late (often requires surgical intervention)
Staph. epidermidis (also known as coagulase negative staphylococci) and enterococcus
what organisms cause late onset prosthetic infection associated with late onset haemotogenous infection
Staph. aureus, beta haemolytic Streptococcus and Enterobacter.
what is the treatment for prosthetic joint infection
usually surgical
antibiotics not given immediatley as may interfere with cultures
can pseudotumours be locally invasive
yes
True or false: A tibial osteotomy may be considered as an alternative surgical option to joint replacement for knee arthritis in the young patient.
true
