Orthopaedics Flashcards
Classification for open fractures?
Gustilo
What can be damaged in a knee dislocation?
popliteal artery
how can a joint become septic? (2)
direct (traumatic)
indirect (haematogenous)
how does septic arthritis present?
Pain
Pseudoparalysis
Pyrexia
which joints most commonly get septic?
IV drug users: Sterno-claviculr
50% knee
20% hip
shoulder, elbow, ankle
basically where joint are within a joint capsule
DDx of septic arthritis?
inflammatory arthritis crystal arthropathy reactive arthritis (transient synovitis) (4-8 yo boys, following URTI) OA acute flare trauma
what criteria indicates likelyhood of septic arthritis in kids
Kocher’s criteria (4 present, 99% probability)
- pyrexia
- inabiilty to weight bear
- WCC up
- ESR up
Ix for septic arthritis
bloods - FBC, ESR, CRP, cultures
plain film, USS
MRI, CT
joint aspirate is gold standard for MCS (delay Abx until this)
surgery for septic A?
washout/drainage
what is compartment syndrome?
increased pressure within a closed fascial compartment leading to impaired tissue perfusion
what percentage of tibial fractures are complicated by compartment syndrome?
1-9%
how to diagnose compartment syndrome?
clinical diagnosis - high index of suspicion
PAIN
- exacerbated on passive stretch of the muscles that traverse the affected compartment
with comatose patients, diagnosis confirmed by compartment pressure monitoring (>30mmHg or not within 30mmHg of diastolic pressure)
Mx of compartment sydnrome?
emergency fasciotomy of ALL compartments in the limb segment affected (full open release)
before:
- relase all casts, slints, dressings
- elevate limb
- analgesia
- prepare for theatre
complications of compartment syndrome
acute (7)
chronic (6)
ACUTE hyperkalaemia hypocalcaemia cardiac arrhythmias rhabdomyolysis renal failure nerve death death
CHRONIC tissue loss weakness chronic pain joint fusions tendon transfers amputation
what is the sail sign in elbow XR
haemarthrosis in elbow - anterior and posterior fat pad
due to intraarticular fracture, or spontaneous
what can be seen on horizontal beam lat XR, with tibial plateau fracture?
Lipohaemarthrosis - escape of fat and blood from the bone marrow into the joint
“FBI” sign - fat-blood interface
what guidelines are used in the management of open fractures?
BOAST4
four stages of (secondary) fracture healing in cortical bone?
- haematoma
- soft callus (cannot be seen on XR)
- hard callus (fibrocartilage ossifies and can now be seen on XR)
- remodelling
intramembranous ossification?
endochondral ossifcation?
- e.g. clavicle, or after cancellous bone fractures (e.g. scaphoid)
- eg. femur
Sx of “fracture disease”
- joint stiffness
- periarticular osteopenia
- loss of function
how do you achieve absolute stability and therefore primary bone healing?
- anatomical (perfect) reduction
- internal fixation
then no callus is formed and bone healed directly.
how do you achieve relative stability and therefore secondary bone healing (ie with callus)?
casts
IM nails (internal splint)
external fixation (shanz screws, clamps)
plates
(all reduce fracture, but allow some movement)
what do you want to do for a long bone and metaphyseal fracture?
maintain length, alignment and rotation
allow relative stability, as that is best for blood supply, over absolute stability.
what do you want to do for articular fractures?
anatomical reduction and absolute stability
Mx of forearm fractures?
anatomical reduction and absolute stability
- what is mortality rate on admission of patients with hip fracture?
- with a year?
10%
50%
Mx of extracapsular?
Mx of intracapsular?
Extracapsular:
- intertrochanteric: Dynamic hip screw (exc reverse oblique)
- subtrochanteric: Intramedullary nail/gamma nail
Intracapsular:
- displaced
- young: fix (with screws)
- old: hemiarthroplasty. ie acetabulum is native,
causes wear and tear and leaves reduced function
- old and good function: Total hip replacement
- undisplaced: fix
Pros and cons of fixation?
Pros:
- quick
- noninvasive
- preserves own hip
Cons:
- AVN 25%
- non-union 15%
what is a contraindication for DHS even though its extracapsular intertraochanteric?
reverse oblique fracture
