Management of specific fractures Flashcards
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Bones anatomy and physiology
Bone overview
Reservoir for stem cells and also lipids and minerals like calcium, so not just structural-also physiological properties
Bone types:
Bone types:
Flat bones eg sternum, skull are bones that protect organs eg heart brain
Long bones-facilitate movement and they are important sites of haematopoeisis so they are unstable if break them
Short bones-as long as wide as don’t have diaphysis
Sesamoid-embedded within tendons-allows for dynamic action, as otherwise would just be one tendon rather than an attachement point halfway through, also protects tendon overstretching.
Bone: anatomy
Epiphysis-end bit which has articular surface
Metaphysis have epiphyseal line where growth plate would sit pre puberty
In epiphysis have spongey bone and in cortex have compact bones
In diaphysis of lng bone, have a medullary cavity of yellow bone marrow
The periosteum, inaddition to arteries, supply blood and nutrients to bone particularly through nutrient arteries.
Bone: ultrastructure
Can have woven (primary bone) first formed in foetal development and also get it in fracture when get bone union
temporary structure, which is replaced by lamellar bone
Bone: ultrastructure
Composition of bone
Important stores of minerals and lipids
Poor vitamin D and calcium will cause bones to suffer
Collagen type 1
Osteoblasts synthesise osteoid, osteocytes are osteobasts that get deposited in osteoid
Osteoclasts are multinucleate cells, that resorb bone and reelase lysosome enzymes and hydrogen ions. The way to distinguish this is the fact it is multinucleate
Osteoprogenitor cells also present
Bone: ossification
2 ways to get bone to grow-
endochondral-temporary cartilage scaffold, replaced by osteoid secreted by osteoblast eg proximal femur, mainly provides length to bone so thin long bones will be this type
Intramembranous-bone forming directly onto fibrous tissue, so think of flatter bones eg temporal and scalpula
Bone: remodelling:
Cutting cone-
- Primarily a mechanism to remodel bone
- Osteoclasts at the front of the cutting cone remove bone
- Trailing osteoblasts lay down new bone
-Undertaken by osteoclasts-get removal by multinucleate osteoclast cells to increase blood calcium levels, but also get production by osteoblasts
Cutting cone-get cutting tip of osteoclasts which cuts bones, followed by trailing series of osteoblasts which then become entombed to form osteocytes. These form concentric lamellae for bone
Bone disorders
- Child=rickets
- Adult=osteomalacia
- Osteogenesis imperfecta=abnormla collagen synthesis
Fracture management:
Fractures-definition
=discontinuity of the bone
4 main criteria
Orientation, Location, Displacement and skin penetration (ie open or closed)
OLDS
eg transverse fracture of proximal femur, it’s displaced and closed
Fracture classification
Wber-for ankle
Universal classification system
AO/OTA classification
Looks at bone and gives it a number eg humerus for 1, number for location eg proximal humeraus is 11, and subgroup type eg 11a will be intrarticular to demarcate fracture.
Fracture healing-primary
Cutter cone not only important for remodelling but also healing
Primary-direct bone healing generally intramembranous healing, very small gap and almost no movement eg less than 500nm, this is very slow process and to have no movement is difficult.
Fracture healing-secondary
Secondary-endochondral healing forms fibrocartilage onto which bone is laid down
Haematoma-damaged blood vessels bleed and neutrophils and cytokines enter area and signal for macrophages, then get soft callus formation, then get calcified matrix deposited as osteoblasts are bought in by blood vessels, then get remodelling (can take 1-2 years to occur)
Fracture: healing pre-requisites
If want primary healing-want little movement and closed gap, but this is hard and some movement is needed for healthy bone healing.
Key is not healing bones but allowing them best option to do so.
Age-younger heal better than elderly in terms of fracturing and remodelling and they can tolerate bigger angular defects
Diabetic-increased risk
Smoking-increased risk of poor bone healing
Fracture healing should take 6 months-would epect to see some callus formation in first 6weeks to 3 months, but full remodelling takes several years. Lower limb fractures take twice as long as an upper limb fractures.
Follow up should be a week after for kids as they heal quicker so if bone heals incorrectly need to intervene
Fractures: bone remodelling
If have deformity when would you know if that was exceptable eg child had femoral fracture that heals in deformed position when put weight on leg on concave periosteum will form more bone and convex side will form less ie will resorb bone, so it will straighten leg. This is wolff’s law and also happens in adults.
Fracture: healing complications
Beyond infection and death, we worry about union and non-union.
Non-union-bone doesnt heal in expected time frame, but if doesnt heal at all= non-union can be due to atrophy might be smoker, or diabetic or delayed presentation. Atrophic-none at all, oligotrophic-not enough
But can also have non-union as a result of too much callus healing, too much movement stimulates too much bone formation-hypertrophic-too much. Horse or elephant’s foot
Union-get callus formation but not within correct alignment=malunion eg patient comes to see doctor late and has healed.
Pseudoarthrosis-get fibrous callus formation which forms like a joint and becomes mobile at that site so isnt a stable contruct. Isnt a type of non-union or union.
Fracture management:
1) Make sure patient doesnt have any life threatening injuries ie resussitate
2) Reduce fracture and bring bone back into alignment, this relieves pain as soft tissue is no longer violated by spikey bones etc. Hopefully will prevent further blood loss and allow haematoma to form
3) Hold fracture in position, no matter what method, to allow time for bone to heal
4) Rehabilitation-muscles undergo atrophy, they get stiffness in their joints so work with MDT and physiotherapists to get their function back.
Any patients with prolonged immobility-will they need VTE if not walking, do they need a catheter, are we going to try and get them up and about and how will we do that?, what support do they need.
Venous thromboembolism (VTE) is a condition in which a blood clot forms most often in the deep veins of the leg, groin or arm (known as deep vein thrombosis, DVT) and travels in the circulation, lodging in the lungs (known as pulmonary embolism, PE).
Fracture management:
Conservative VS surgical
-Injury but dont have break eg think ligamentous or soft tissue, advise RICE, don’t aggrevate, allow it to heal.
Casts-reduce fracture and then resting it-casts are god way to do this-can be made of plaster or fibreglass which is much more light weight. Circumferential cast goes all way around, bad for swelling as will limit blood flow and compress internal structure as can’t push out so can cause compartment syndrome. Back slab is used in acute setting, but it is not an official cast, after surgery would provide circumferential cast or to children. A ‘back slab’ is a slab of plaster that does not completely encircle the limb and is used for injuries which have resulted in a large amount of swelling. It is secured with a bandage to accommodate the swelling. This type of plaster is only temporary and will probably be ‘completed’ at your Fracture Clinic appointment.
What if you can’t cast certain area?
=traction, important for long bone fractures eg femur and humerus. In femur can do bone or skin traction. Apply sticky bandage and hang weight over it to straighten the bone out with traction and they are reconstituted and people get immediate relif. In humerus dont use traction as much, use gravitational pull via collar and cuff to bring bone back in alignment.
Internal fixation-MUA-manipulation under anaesthetic (closed or open reduction of fracture), then use K-wires to hold fracture position inside. Useful in kids as have very thick periosteums which can displace fracture alignment from holding in place.
ORIF-common, open reduction internal fixation, can do closed RIF using minimal invasion, but generally ORIF. Clean up and then apply plate or screw to hold in place. Plate, screws and K-wires are extracortical so go on outside of bone.
Intramedullary go inside bone and are useful for long bones eg tibia, really devices that are temporary. In long bone, may not be amednable to plate eg skin overlying shin is minimal so soft tissue may break down with plate and it would be really obvious, or there may be important structures in the way that means intramedullary is needed instead. In tibia go anterograde, this is dangerous if inexperienced surgeon.
External fixtures are different-monoplanar or biplanar is one that sits within a single plane or 2 planes. Goes inside skin through nick and then apply rods on outside and build a contruct that allows stability for fracture patern. Why not just put nails down? External fixture may be used due to an open fracture so can’t put metal inside as it would be exposed to air and bugs would get in and soft tissue may not be big enough to allow it to be closed and to get a graft from somewhere else is so much hassle. External fixture is very quick and easy, allows pins to be placed away from soft tissue defect. These are not just useful for soft tissue injuries like open fractures or swelling, but they are also useful for patients who won’t comply with ORIF or intramedullary ones.
Cold use multiplanar ring for people with non-union after healing and will provide a more rigid than mono or biplanar, but pick patient wisely as will get to know these patients, want them to be compliant as will be seeing them all the time.
Beyond internal and external is surgical intervention
Have hemi and total joint replacement-affect joints eg trauma cases.
Radiograph interpretation:
Fractures: Assessment
Get fractures in 2 planes
Clinical relevance – Fracture Imaging
Approach to orthopaedic X-rays:
How do you assess a radiograph-6 things
1) Projection-2 views plus to see everything, scaphoid get 4 views
2) Patient details
3) Technical adequacy
4) Obvious abnormalities
5) Systematic review of X-ray
LOSS is a mneumonic for the X-ray signs of osteoarthritis
6) Summary
