Ortho Med Unit 1 Flashcards
What immune cells are associated with acute and chronic infection?
Acute: polymorphs
Chronic: lymphocytes
What type of osteoarthritis is the most common?
Primary (unknown cause) - may be as a result of injury, however the cause is unclear
What can be the causes of secondary arthritis?
Trauma, Childhood disease (Perthes, infection), Congenital (CDH), Metabolic (gout), Infection (TB), Inflammation (RA)
When is secondary referral necessary for osteoarthritis?
When the pain is no longer controlled by analgesia and is disrupting sleep
What is found on examination of osteoarthritis?
Pain
Limited ROM
What are the symptoms of OA compared to RA?
OA: usually later in life, gets worse with movement, pain worsens during the day, usually unilateral
RA: usually in middle age, worse in morning, improves with movement, bilateral
What are the conservative management options for OA?
Weight loss - joint loads can be several times body weight, therefore a small amount of weight loss can have a significant affect on the joint load
Walking stick - transfers weight to the shoulder girdle so the abductors don’t need to contract which hugely reduces muscle induced hip loading
Rest + physio - balance is required, some exercise relieves stiffness and muscle spasm but too much is counterproductive
Analgesia
What are the surgical management options for OA?
Nothing - risks may outweigh benefits
Arthrodesis - joint fusion
Osteotomy - removing a wedge of bone
Arthroplasty - replacement
What are the benefits of arthrodesis in the hip?
If arthroplasty is not a safe choice (such as in a young patient),
Can be revised into joint replacement later in life
Useful in the ankle and wrist
Hip is fused at 30º flexion + some abducton which allows normal gait + sitting (Not popular with women as it interferes with female sexual activity)
What are the pros/cons of osteotomy to manage OA?
Redirects joint forces so they are more evenly distributed
Used when there is a deformed to the joint (ie bow legged walking at the knee)
Useful in early stages for young patients
Once ROM is serenely limited is ineffective
What are the principles of surgical intervention in orthopaedics?
To reduce pain + stiffness (improve functional ROM) and make diseases manageable
What are the principles required by an arthroplasty?
To allow functional and pain free ROM
(will improve pain related loss of function but won’t be able to help with intrinsic stiffness)
Must be able to withstand large forces placed upon it without wear or working loose + have the same stability as the natural joint
What are the limitations of arthroplasty?
Will not alleviate disability due to stiffness, only pain
Wear begins as soon as it is put in (as artificial, a natural joint would regenerate itself) so require a joint that would outlast the likely lifespan of the patient (therefore in younger patients alternatives are required)
What is required of a hip arthroplasty?
Must be able to withstand very large loads
Relatively low functional ROM required for activities of daily living
What is required of a knee arthroplasty?
Requires 90º flexion for stairs, but otherwise very low ROM required
Muse be stable in extension to support full weight on a single leg (ie for walking) - therefore ligaments must be balanced
What is done to the collateral ligaments of the knee during arthroplasty?
They must be balanced so the MLC/LCL are under equal tension (may need to cut tight parts + add artificial replacements)
What are the general complications of an arthroplasty?
Chest infection
UTI
Pressure sores
DVT (+ PE)
Most patients are elderly which means they are more likely to have medical conditions predisposing them to risk
What are the early complications of a joint replacement?
Dislocation
DVT
Infection
What are the later complications of joint replacement?
Infection
Loosening + wear
When is surgery used in the management of RA?
What is the aim of surgery
If control by drugs is inadequate, otherwise doing the patient a disservice
To improve function but not correct any deformities (deformed hands can have very good function)
Describe the surgical procedures used for RA
Synovectomy: removal of diseased synovial tissue (such as tendon sheaths) - useful in young patient who has good function, but pain
Excision arthroplasty: removes part of the joint - will relieve pain but will never have a full return of function so should be thoroughly considered
Where does post traumatic AVN most commonly occur?
Femoral head, scaphoid, talus
What are the non traumatic causes of AVN?
Chronic alcohol abuse
High dose steroids
Deep sea divers (Caisson’s disease)
How does AVN present?
Acute + severe joint pain
Made worse by movement, relieved by rest
Mostly young patients
How is AVN diagnosed?
Hard to diagnose
Very late X-rays the bone appears more dense as there is lack of blood vessels
How is AVN managed?
If blood supply is naturally re-established will be reversed (soft bone prone to secondary OA)
Cannot surgically restore blood supply
Joint replacement (patients usually young which presents challenges)
What crystals are deposited and gout and psudogout?
Gout: urate crystals
Pseudogout: pyrophosphate crystals
How does gout/pseudogout present?
Hot, tender, swollen joint
How is gout managed?
Usually self limiting but require anti-inflammatory drugs to reduce inflammation + analgesics for pain
What joints are most commonly affected in gout and psudogout?
Gout: knee + 1st metatarsophalageal (big toe)
Pseudogout: knee
What is the cause of acute septic arthritis?
Bacteria which has spread from another location (ie boil)
In adults, very rare unless the joint already damaged or immune system weak/dysfunctional (usually due to gonococcus (STI))
How do children vs adults present with acute septic arthritis?
Children: acute illness with high temperature - stiff, hot + tender joint
Adults: mild illness but progresses to blood poisoning - mortality is high due to the delay in diagnosis
How is acute septic arthritis managed?
Surgery + IV ABx (joint surgically opened + washed)
What is the risk if management of acute septic arthritis is ineffective?
Septicaemia with disintegration of the articular cartilage + fibrous/bony fusion of the joint
What is the cause of chronic septic arthritis
Usually TB which is spread to joints via the blood (mostly found in undeveloped countries and patients with AIDS)
How does chronic septic arthritis present?
Chronic ill health, weight loss, muscle wasting around affected joint
How is chronic septic arthritis managed?
Drug management over several months (very rarely require surgery)
What are the symptoms of mechanical causes of knee pathology?
Swelling, locking, giving way, pain
How does a meniscal lesion present?
Pain, effusion (swelling), locking/giving way, generalised discomfort from extending the knee
How does a meniscal tear occur? Which meniscus tears more often?
A twisting injury where the foot gets stuck on the ground and the femur twists on the tibia causing a wrenching on the meniscus (skiing/games with studs)
Medial
What are the types of meniscal tear?
Bucket handle: a vertical tear which is anchored at both ends, the loose flap can fold under the femur preventing extension of the knee
Parrot beak: one end of the meniscus tears off
Degenerative tear: due to degeneration of the meniscus
How is a meniscal tear examined and managed?
Examination: arthroscopy (camera inserted into knee joint)
Management:
the torn part should be surgically removed (arthryiscopuc meniscectomy - short recovery time)
Peripheral tear can be repaired with sutures
What are loose bodies?
Small fragments of cartilage or bone that may be sheared off during injury
Knee will initially swell from haemarthrosis (bleeding into joint)
The fragment can live in the synovial fluid for months or years without causing problems
How do loose bodies present?
Locking, pain, giving way, effusion
What is osteochondritis dissecans?
Disease causing spontaneous loose bodies in children - spontaneously resolves but may require removal of loose bodies
How are loose bodies removed?
Using arthroscopy
How do collateral and cruciate ligaments heal?
Collateral: have a good blood supply so heal spontaneously
Cruciate: poor blood supply so do not heal themselves if torn
How do lesions of cruciate ligaments usually occur?
Either a hyperextension or twisting injury
How does an ACL/PCL tear usually present?
Initial ‘pop’ at the time of injury
Immediate swelling from haemarthrosis (bleeding into the joint)
What are the chronic symptoms of a cruciate ligament lesion?
Loss of anteroposterior stability (especially in flexion - when going up/down stairs)
Loss of rotary stability when twisting/turning
How is a cruciate lesion managed?
Left untreated for a while to allow rehab of knee muscles
Surgical management should only be offered in symptoms interfere with daily life/patient wants to return to sport
Torn ligament is replaced with a synthetic one
Why is a synthetic ligament more likely to fail?
There are no sensory receptors to the brain if it is being overstretched - can’t initiate muscle action to protect the joint
What is the cause of patellar dislocation?
Malformation of the patella or lateral femoral condyle - causes abrasive movement of the patella on the femur causing pain from muscle spasm
What happens when there is spontaneous dislocation of the patella?
The person will fall to the ground as there is failure of the extension action of the quads muscle (dangerous as it happens without warming)
How is patellar dislocation managed surgically?
Minor mal-tracking: splitting of the vastus lateral muscle insertion onto patella to allow normal relationship with femur
Recurrent/severe: medial tightening of the vastus medals muscle to sit the patella more medially (plication)
