DIAG: Synovial jt

• Knee has hyaline cartilage and meniscus (fibrocartilage)
• Weight-bearing part is hyaline cartilage
• Articular cartilage, subchondral bone, synovium, fibrous capsule, ligaments, tendons, muscles, nerves, vessels, bursa

Prerequisites for joints (movements and force transmission)

1. Pain-free
2. Stable: for bearing wt - eg. Hip and knee in lower limb
3. Mobile

• Inflammation of a joint - pain, hotness, redness, swelling, loss of function
• The joint becomes painful, stiff or unstable, deformed and does not function properly
• Deformity: may affect function; results in poor self-image (eg. RA tries to hide hands from others)
• X-ray Pelvis: femoral hears destroyed, pelvis grossly affected

1. Early: stop synovitis
2. Gross subluxation: Pt needs surgery (improve function and decreased pain)

• Distinguish between RA and OA: look at marginal aspect (1) OA has osteophytes (2) RA has erosion
• RA affects mainly peripheral jts
• Female:male = 4:6

• Less common
• Related to RA
• Autoimmune disease
• AS affects spinal column: stiffness of spine limiting their excursion and visual angle
• AS is HLA B27 positive (>90%)
• Male:female = 9:1
• HKAS Association + B27 Association
• Severe: 'question mark' deformity -> affect ADL
• Measure spinal excursion: measure 2 bony landmarks about 10cm apart (while in upright position), then bend fwd as much as possible, distance should increase from 10 to 15cm (in AS: 10cm then 10cm, because all movt occurs at hips)
• Measure chest expansion: ask Pt to take deep breath, measure chest expansion, AS: costal vertebral jts may be ankylosed, which limits chest expansion
• X-ray sacroiliac jt (most commonly affected in AS) - earliest affected
• X-ray spine: bamboo spine - ossification of anterior and posterior longitudinal ligaments and intervertebral discs (these are late changes)
• Therefore, if you can only take one X-ray, take X-ray of SIJ

• Failure of hyaline cartilage (important component of jt)

1. Primary: age-related
2. Secondary: marathon runner (increased usage and vigour)

• Crystals are needle-shaped
• Gout - sodium urate: needle-shaped
• Pseudogout - calcium pyrophosphate: rhomboid-shaped, polarised light
• Shape of crystals has no bearing on pain (it is a chemical synovitis)
• Chronic elevation of uric acid level in blood - accumulation of crystals affecting feet, hands, elbows, ears (tophi) [if you suspect gout: ask to look at Pt's ears]

• Rheumatoid arthritis - synovitis - stop the synovitis e.g. non-steroidal anti-inflammatory drugs (NSAIDs), disease-modifying anti-rheumatic drugs (DMARDs); if these fail, surgical removal of the inflamed synovium (synovectomy)
• Osteoarthritis - wear and tear of the cartilage due to overload - reduce the load e.g. reduction of the body weight, modify the daily activities
• Gout - hyperuricaemia - find out the cause - diet and medications

1. Drugs

• NSAID
• DMARD: Disease Modifying Anti-Rheumatoid Drug
• Medication depends on primary pathology
• Uricosuric agents for gout but not for pseudogout
• OA: simple painkiller without any inflammation (eg. Paracetamol): jt in OA usually not hot and swollen, therefore no cardinal features of inflammation
• OA = osteoarthritis or osteoarthroses
• RA: used to only use NSAID and if they didn't work, kept switching type of NSAID until effect - problem: if admit failure, the jt is already grossly affected. Therefore, new methods include DMARDS right form the outset (eg. Methotrexate)

2. Exercises e.g. mobilisation, muscle strengthening

• Once inflammation has subsided, start jt mobilisation
• Strengthening: stability of jt (static stabilisers - capsule and jt) (dynamic stabilisers - muscles) if muscles are weak, all force goes to static stabilisers, and if these are weak, there will be problems with jt stability

3. Rest - Splintage e.g. to stop the deformity from progressing

• Immobilise hand in functional position
• Immobilise knee in extended position (extended when standing, therefore do not immobilise in flexed position)

• Surgically remove inflammed synovial tissue
• If not removed, will erode into bone and cause destruction
• Open surgery
• Endoscopy: shaver
• Only for 1st and 2nd stages of RA (last stage: even if you remove synovium, jt is still destroyed)

• Pain-relief ++, stable ++, mobile +; not for all situations (the joint is partly affected and still has a good part to receive the re-distributed load; to correct gross spinal deformity in ankylosing spondylitis)
• Redistribute stress to normal area
• Remove wedge-shape near jt, join remaining ends
• Infrequent procedure in Chinese (pain usually not so severe, Chinese Pt's wait a long time until further changes, then osteotomy will redistribute stress to another abnormal area)
• Success: jt only partially affected, need normal part to redistribute stress to

3. Fusion (Arthrodesis) -

• Pain-relief ++, stable +++, mobile -; if minimal disability after fusion; may have effects on other joints; not if it is bilaterally involved
• Not done in hip, knee, shoulder, elbow (we need to maintain mobility)
• Ankle, upper cervical spine: jts diseased and show instability - can fuse joints
• Eg. Spine, artificial replacement of discs is not successful yet, therefore fusion more common

• Pain-relief +, stable -, mobile ++; non-weight bearing small joints

• Artificial jt replacement
• Pain-relief ++, stable ++, mobile ++; large joint which good range is important; not permanent (loosening and component wear)
• Similar to dental procedure: remove diseased tissue and cap with artificial tissue
• There are not artificial materials for joint replacement that will last life-long (wear and tear)

• Soft tissue procedures
• Synovectomy
• C1-2 fusion in rheumatoid arthritis
• Arthroscopic debridement and removal of loose bodies in osteoarthritis (of the knees)
• Spinal osteotomy in ankylosing spondylitis

• Fuse both knees: can walk straight-legged, but cannot rise from sitting position (require 90 deg knee flexion)
• Fuse both hips: can walk with trunk doing the work, but interferes with sexual intercourse, normal vaginal delivery not possible

• Future surgeries have better materials and techniques: therefore should be better
• But, future surgeries, the Pt will be older, therefore decreased activity levels, therefore less wear and tear
• Most jt replacements last more than 10 years

• Psychosocial problems
• Social worker
• Other health professionals
• Team work needed