Joint Conditions Flashcards
What type of cell is found in acute joint conditions?
Polymorphonuclear leucocytes (polymorphs) Called such because their nuclei are in many sections and appear white under microscopy
What type of cell is found in chronic joint conditions?
Lymphocytes
Produced in the bone marrow and the spleen
What is the main aim of treatment of OA?
To relieve pain and stiffness, since many joint conditions are incurable and will inevitably get worse with time
(examples of self-limiting MSK conditions: muscle tears, ligament sprains)
Example of a metabolic disorder which can lead to joint inflammation?
Gout - inflammation caused by aric acid crystal deposition on the cartilage, which is a waste product of DNA metabolism
Name the 2 principal symptoms in orthopaedics?
Pain and Stiffness (leading to loss of normal function of joints)
What does ‘orthopaedics’ mean?
Literally ‘straight children’ as it used to deal with abnormalities of children as they grow and develop, but now deals with the MSK system
What is osteoarthritis?
A condition of pain and limitation of movement of joints assoc w excessive wear of articular cartilage resulting from a breakdown of balance between wear and repair processes in the joint. It is more common with increasing age, but does not inevitably accompany old age.
What is primary OA?
When there is an imbalanced wear and repair mechanism on the articular cartilage, but no other secondary condition causing the damage. More often it is a problem with increased wear.
What is secondary OA? 6 Causes?
Obvious causative factors which can be assumed responsible for causing OA:
- Congenital - congenital dislocation of the hip
- Childhood - Perthes’ Disease (compromised blood supply to femoral head causing AVN)
- Trauma (e.g. fracture)
- Metabolic (gout, crystal arthropathy)
- Infection (septic arthritis, TB)
- Chronic inflammation (rheumatoid)
Hx of osteoarthritis?
Joint pain assoc w activity followed, and for <30min in morning
Stiffness follows pain
Can often feel tired due to excess effort required to move and disturbed sleep due to pain
Examination of OA?
There is pain and limited range of movement during examination of the joint. Muscle wasting may be present due to disuse.
If examining under anaesthetic there is an increased range of motion, therefore results of surgery related to pain relief rather than improved mobility
Conservative treatment options for OA?
Weight loss
Walking stick
Rest & Physio
How does weight loss help in OA?
Lower limb joints are subject to very large loads due to leverage exerted by muscles around the joints - when walking the hip is subject to 3x body weight during the stance phase, and during activities of greater hip muscle exertion joint load can reach 5x body weight. Therefore, modest reductions in body weight lead to large reductions in force through the joints.
How does a walking stick help in OA?
Use of a stick in the opposite hand means the shoulder girdle can help in tilting the pelvis and so help in weight bearing. Normally when we walk, when we have our weight on the right side, the right gluteal muscles contract to tilt the left side of the pelvis upward, letting the left leg swing forward without making contact with the ground. The use of a stick has the effect of reducing the work required by the abductor muscles thereby dramatically reducing muscle induced loads on the hip.
How does physiotherapy help in OA?
Balance is required: over-exercise can be detrimental but some exercise allows relief from stiffness and muscle spasm, and therefore pain. Sufferers should be advised o avoid excessive unnecessary exercise and change to a light job if possible. Total rest, however, is counterproductive, especially in the elderly, because muscles work most efficiently when they are in regular use. Stretching them in exercise helps them maintain natural tone, whereas excessive rest around a painful joint will make the muscles go into spasm, which is painful and inhibiting
Surgical options for OA? (4)
Do nothing
Arthrodesis
Osteotomy
Arthroplasty
Considerations around NOT performing surgery in OA?
Risks may outweigh benefits
If severely disabled and in a great deal of pain, surgery may be considered, but only after careful planning and full explanation, and provided patient has a full grasp of the risk
What is arthrodesis? Who is it most useful for? How is it done? When might it be problematic? Why is it difficult for the hip?
Surgical stiffening of a joint in a position of function - this is more appropriate for a young person with a painful joint with limited ROM.
Articular cartilage is removed and the raw bone ends are held together by an external splint until a bony bridge forms between the bone ends. In the hip this is usually done at 30 degrees flexion with slight adduction, allowing functional gait and sitting.
However, this is not always acceptable for females as it interferes with sexual activity.
Fusion is technically difficult in large joints such as the hip because the bones are difficult to hold together - the operation requires prolonged recovery of 6 months and often a plaster splint.
Long term disadvantage of arthrodesis?
How is this overcome?
Which joints is arthrodesis most successful in and why?
Long term disadvantage is that it puts stress on adjacent joints, e.g. for the hip this means the lumbar spine, knee and contralateral hip. This problem can be anticipated by electing to fuse e.g. until the 5th decade, then attempting to ‘unpick’ the fusion and convert to an arthroplasty, which is surprisingly effective.
Some joints can be very successfully fused, however, including the ankle and wrist. This is because they are small joints so easier to hold together, they don’t require a huge functional ROM, and because these joints are difficult to replace.
What is osteotomy?
When is it used?
How long does it last?
How is it performed in the hip?
Surgical realignment of a joint - the aim is to redirect forces across a joint so they more evenly distribute the load, and is generally performed when the joint has become deformed e.g. if someone with rickets has become bow-legged the forces travel down the medial aspect of the knee joint rather than the centre.
It is useful in arthritis when the patient has retained a good ROM despite the pain, typical of early stage OA. Conversely, if the ROM is severely limited then a simple realignment is unlikely to succeed because useful function cannot be restored.
It is often a temporary measure, for any condition (arthritis, bow leg etc), lasting around 2-10 years, because the underlying cause of the problem may not have been tackled.
In the hip it can be performed on the pelvic side, by performing a shelf or total acetabular realignment, or on the femoral side by altering the angle of the femoral neck.
What does arthroplasty mean?
Replacement of one or both surfaces of a joint - it can alleviate pain and restriction of ROM, but will not help stiffness (due to greater coefficient of friction)
Why are joint replacements not permanent?
They are not live tissues, they are artificial, therefore have no capacity to regenerate, and from the minute it is first used it will begin to gradually degenerate
Why is joint replacement more difficult in the upper limb than the lower limb?
In lower limb joints, the loads are high and the functional ROM required is low.
In upper limb joints, the loads are not so high but the functional ROM required is high. Arthroplasty alleviates pain-related loss of function, but not stiffness, because the soft tissue distortion of the capsule and ligaments tends to remain after replacing the articular surface.
E.g. the elbow must flex to 90 degrees to eat and fully extend to reach anus for cleansing after defaecation, which is a demanding functional ROM, and the technology isn’t quite up to standard yet.
3 requirements of an artificial joint?
Functional and pain free ROM
Withstanding the significant force placed on it without undue wear or working loose
Having the same stability and resistance to forces as the natural joint
What ROM does the hip retain after an arthroplasty?
10-15 degrees Extension
30 degrees Flexion
A few degrees Abduction
A few degrees Rotation
Specific functional requirements of a knee replacement?
How is this achieved
It must flex to 90 degrees to ascend stairs, and must be stable in full extension to suport weight whilst standing on one leg.
To achieve this, there must be an accurate balance of soft tissues through dissection of the capsule and ligaments. The surgeon must balance the collateral ligaments by cutting tight parts and putting in artificial replacements of sufficient thickness to re-tighten the ligaments, so that medial and lateral are under equal tension. This is because bone erosion in OA leads to distortions in the ligaments (which further leads to deformities and pain of OA).
4 potential complications for anyone undergoing any surgery?
Chest infection
UTI
Pressure Sores
DVT
(sores and DVT particularly with any pelvic surgery, hip replacement or knee replacement)
3 specific early complications of arthroplasty?
DISLOCATION
DVT (and PE)
INFECTION
