Joints Flashcards
Synovial joints
most appendicular joints hyaline cartilage smooth and self-lubricating connected by fibrous capsule contains synovial fluid more movement but less stable
Syndesmosis joint
two bones bound by fibrous tissue only
e.g. skul, ankle (tibia-fibula)
Synchondrosis joint
two bones bound by cartilage
e.g. physis - between diaphysis and epiphysis during bone growth
can be pathologic, failur eto ossify
Synostosis
joint obliterated by growth of bony union
e.g. fusion of pelvis
can be pathologic
Symphysis
Opposing surfaces of joitn covered by cartilage
minimal movement, no synovial fluid
e.g. pubic symphysis, intervertebral discs
Gomphosis
joint between tooth and socket
fibrous connection between tooth and socket
blood vessels and nerves cross joint
Sesamoid bone
bones that increase the mechanical advantage of a tendon
better at compression than tendon tissue
e.g. patella
Ligament
thickening of fibrous capsule around the joint to form a band of tissue that resists a specific motion
Tendons
Connects muscle to bone, crosses joint
responsible for force transmission to cause movement of joint
deals with both tensile + compressive forces
Tendon structure
structure is similar to muscle structure
epitenon: covering of outer tendon
- contains blood supply, proprioceptive and sensory neurons
Collagen fibrils –> collagen fibers –> primary fiber bundles –> secondary fiber bundles (fascicles) –> tertiary fiber bundles –> tendon
Type I collagen predominant proteoglycan matrix fibroblasts arranged in rows - few in number - produce matrix - communicate through gap junctions
Tendinitis
implies inflammation, but rarely happens in reality
does not respond to anti-inflammatories or icing
lack of evidence of inflammatory cells in tendon
Diseased tendon
disordered arrangement of collagen increased cellularity (myofibroblasts) increased matrix protein increased vascularity absence of inflammatory cells apoptosis of tenocytes
Tendinopathy
“tendon problems”
includes:
Tendinosis - degeneration of tendon without evidence of inflammation
- better term than tendinitis
- started by increased demand on tendon
- without adequate repair - leads to tenocyte death, further exacerbating inadequate collagen and matrix production, which predisposes the tendon to further injury
- partial rupture
- paratenonitis: inflammation of paratneon (material between tendon and its sheath)
Tendinopathy imaging
US
good for differentiating rupture and teninopathy
image does not correlate to symptom severity
Tendinopathy management
Rest
- collagen repair takes a long time
- advanced by the time pain is felt
- 2-3 weeks before strengthening
- combine with biomechanical deloading - braces, taping
Address predisposition
- running posture
- flexibility
- changes at work
Strengthening
- eccentric strengthening is the most effective
- accelerates tenocyte metabolism
- important component of healing + improvement
Treatment
- NSAIDs - limited use due to lack of inflammation, can use in paratenonitis, bursitis, no evidence for benefit in tendinopathy
- surgery: last resort, long rehab period, does not stimulate collagen synthesis
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