MSK - Bilateral Knee Pain Flashcards
(24 cards)
What is Enthesitis?
Inflammation of the entheses i.e. the sites where tendons or ligaments insert into the bone
- Associated with HLA B27 arthropathies particularly seronegative ones - remember via PAIR mneumonic:
- Psoriasis / psoriatic arthritis
- Ankylosing spondylitis
- Inflammatory bowel disease
- Reactive arthritis
How many joints are affected when the following terms are used?
- Monoarticular
- Oligoarticular
- Polyarticular
- One
- ≤ 4
- > 4
Which joints are often affected by Osteoarthritis?
- Large-weight bearing joints (Hip, knee, ankle, lumbar spine, cervical spine)
- Foot: MTP
- Hands: CMC, PIP and DIP, 1st IP, 1st MCP
What is Diclofenac (Voltarol)?
It is a NSAID used for pain/inflammation relief in:
acute gout, rheumatic disease and postoperative pain
If a patient presents with a recent history of exacerbation of pain/stiffness at the knee joint with swelling, what conditions might you consider?
Of those conditions which is diuretics a risk factor for?
- Crystal - gout / pseudogout
- Septic arthritis
- Mechanical disruption (meniscal, ligaments, bursa)
- Rapidly progressive OA
- Osteonecrosis
Diuretics are a risk factor for Gout
What features of a joint examination might indicate an osteoarthritic joint?
- Cool effusion (warm indicates inflammation/infection)
- Pain on movement
- Reduced ROM
- Crepitus
- Antalgic gait
- Weakness +/- muscle wasting
- Joint line tenderness
- Deformity
- Bony swellings (osteophytes)
- Joint instability
What are the names given to bony swellings / nodal osteoarthritis at the:
- PIP joints
- DIP joints
- Bouchards nodes
- Heberdens nodes
What condition do these hands likely show?
Osteoarthritis
- Bouchards nodes: left (2,4,5) right (4,5)
- Heberdens nodes: left (2-5) right ( 2-5)
- Z-thumb both hands
What investigations might you do in someone with suspected OA?
Investigations:
- Bloods:
- Inflammatory markers - CRP/ESR (rule out inflammatory condition)
- FBC + U+Es - assess baseline
- If concerned about inflammatory overlap then Rf and anti-CCP
- X-ray of afflicted joints and common offenders i.e. hands, ankle etc.
What are the X-ray features of OA described by the LOSS mneumonic?
- Loss of joint space
- Osteophytes on the joint margins
- Subchondral bone sclerosis
- Subchondral cysts - small pseudocystic areas with sclerotic walls situated in the subchondral bone
What are the management options for OA using the CAN mneumonic (Conservative, pharmacological, surgical)?
Conservative:
- Patient education
- Weight loss
- Exercise/physiotherapy
- Appropriate footwear + walking aids
Pharmacological:
- Analgesia
- Topical NSAIDs / capaiscin cream
- WHO Ladder – paracetamol, NSAIDs, opiods
- If prescribing oral NSAIDs also consider PPI for gastroprotection
- Intra-articular steroid injection for moderate to severe pain
Surgical:
- Surgery is considered in pts with symptoms that have a substantial impact on quality of life and are refractory to non-surgical treatment
- Many different options
NICE guidelines say we should diagnose OA in patients if they meet 3 conditions, what are they?
- Pt is 45 or over AND
- has activity-related joint pain AND
- has either 1) no morning joint-related stiffness or 2) morning stiffness that lasts no longer than 30 mins
What is the most common form of arthritis?
Osteoarthritis
- 50-80% of the population will have radiographic evidence of OA >65 years
- ~ 3% of the population have symptomatic OA
- Often progresses gradually but can be rapidly progressive e.g. 1/3rd of knee OA
What are the risk factors for OA?
- Age > 50
- Gender F > M
- BMI
- Previous joint injury
- Intense sport activities
- Occupation (hand, hip)
- Quadriceps strength (knee OA)
- Alignment (knee OA) e.g. valgus (knocked knees) or varus (bow legs)
- Genetic
- Secondary OA
- Pistol grip deformity (hip) - x-ray sign of CAM-type femoroacetabular impingement (proximal femur is shape of flintlock pistol)
What is ‘Pistol grip deformity’ of the hip?
It is a radiological sign of cam-type femoracetabular impingement - this is a syndrome of pain + limited hip motion
- Caused by morphological abnormality of femur head / neck
- Cam-type = aspherical shape of femoral head due to bony protrusion, commonly at the anteriosuperior aspect of femoral head-neck
What is the main modifiable risk factor for OA?
BMI
What are some secondary causes of OA?
Here are some useful headings:
Metabolic, traumatic, anatomical, neuropathic, inflammatory
Metabolic:
- Crystal-associated (gout, calcium pyrophosphate i.e. pseudogout)
- Acromegaly
- Haemachromatosis
- Wilson’s disease
- Haemoglobinoathies
- Collagenopathies
Traumatic:
- Joint injury
- Surgery e.g. meniscectomy
- Fracture through a joint or osteonecrosis
Anatomical:
- Slipped femoral epiphysis
- Epiphyseal dysplasia
- Legg-Perthe’s disease, Blount’s disease
- Congenital dislocation of the hip
- Unequal leg lengths
- Hypermobility syndromes
Neuropathic:
- Diabetes
- Syphilis
Inflammatory:
- Any inflammatory arthropathy
- Septic Arthritis
What is the function of articular cartilage?
Shock absorbtion + gliding of bones
What are the common presenting features of OA?
- Joint pain - worse on movement / exercise, relieved by rest
- Morning stiffness lasting < 30 mins
- Night pain - can occur in severe OA
- Knee malalignment - knee valgus (knocked) /varus (bow)
- Muscle wasting
- Palpable bony swellings (osteophytes)
- Joint effusions (cool - not warm as in inflammation)
- Crepitus on joint movement
As OA progresses what pathophysiological joint changes occur?
- Joint tissue macrophage stimulation –> ↑ cytokines (TNF-alpha, IL-6, VEGF etc) –> immune cell joint infiltration + neovascular growth
- Immune cells –> ↑ proteases –> articular cartilage break down
-
Age also thins cartilage:
- ↓ hydration of cartilage
- ↑ brittle bones
-
Age also thins cartilage:
- Cytokines stim osteocytes –> stim osteablasts –> bone deposition in the form of subchondral sclerosis + osteophytes
- Other cytokines in joint e.g. prostaglandins and bradykinin –> stim pain fibres
What is a syndeosmophyte?
Is a bony growth inside a ligament (often spinal ligaments of the intervertebral joints - leading to fusion of vertebrae)
- Similar to osteophytes
- Ankylosing spondylitis patients = prone to syndesmophytes
what is the stepwise management of analgesia in OA?
- Oral paracetamol + topical NSAID/capsaicin!
- Oral NSAIDs + PPI (not constantly)
- Opiates (not effective long-term → tolerance)
What advice would you give post-hip replacement to minimise risk of disclocation?
- avoid flexing the hip > 90 degrees
- avoid low chairs
- do not cross your legs
- sleep on your back for the first 6 weeks
What are 3 common complications for hip replacement?
- wound and joint infection
- thromboembolism (NICE recommend patients receive low-molecular weight heparin for 4 weeks following a hip replacement)
- dislocation (remember advice)
- patients receive both physiotherapy and a course of home-exercises
- walking sticks or crutches are usually used for up to 6 weeks after hip or knee replacement surgery
