There are 3 types of knee pain and they are Injuries, Arthritis and Gout.
1. Injuries (Ligament, Meniscus, Cartilage, Bone)
1.1 Ligament Tear
ACL Tear
- The most common ligament tear
- Twisting injury during sports
- Loud "pop" sound
- Inability to walk
- Immense pain and severe swelling
Symptoms
Instability
“Disconnected”
ACL is the most important ligament for rotational movement
Treatments
Initial Stage- Interim period bracing
- Anti-inflammation and Physiotherapy
- If initially more swollen and painful the doctor might e.g withdraw water from knee joint
- 1 month - 6 weeks of rest before the second stage
Second Stage- Bracing
- BRACE brand - Ossur (not bulky, the material is breathable)
- If you’re a couch potato with no exercise — may not need surgery done
- If you’re active, play sports — may need to surgery
- Ligaments don't heal by themselves!
ACL reconstruction
- Minimally Invasive Surgery (Keyhole surgery)
- Day surgery or 1-night stay
- Aims to return to sports in 3-6 months
1.2 Meniscus Tear
- Fibrocartilaginous tissue
- Stabilisation and load distribution
- Sports injuries/degenerative
- Pain, swelling, locking
Characteristics
- Located in between knee joint; Thigh bone and leg bone
- Most common causes are sports injuries
- Ligament and meniscus can occur at the same time or separate timing
- Injury can be minor or trivial, e.g. climbing onto a bus at a wrong angle, incidents like these can cause it
- Meniscus tears in the elderly cause pain and swelling and can cause something called locking
- Knee joint locks, then suddenly able to move again
1.3 Cartilage
Normal Cartilage
- Avascular tissue, lacking lymphatics and nerves
- Smooth and resilient
- Allows sharing and compressive forces to be dissipated uniformly across joints
Taking pressure at the injury site can damage cartilage, e.g. falling directly on the knee cap and knee hurts, swells up, or repeated injuries such as in teenagers playing rough, or you wonder why your knee has many clicking sounds; as time goes by all the friction and wear can lead to pain and cartilage damage.
Cartilage Injuries
- Direct
- Repetitive
- Pain, swelling
- Clicking
Treatments
Microfracture technique
- Extract bone marrow, in the hopes that cartilage can regrow
- Stem cell slowly releases
- Better technique — implant empty cartilage cells to stay inside and proliferate and prevent further friction in the knee joint, by reducing and repairing knee function.
2. Arthritis
- “Arthro” means joint, “itis” means inflammation.
- Most common is Osteoarthritis (meaning normal wear and tear)
- Rheumatoid Arthritis — unfortunate, immune system fighting own joint — happens in hands and knee joints
- All injury can happen together or separately
- If the whole joint is damaged beyond repair — consider joint replacement
Cartilage
Normal Cartilage
- Avascular tissue, lacking lymphatics and nerves
- Smooth and resilient
- Allows shearing and compressive forces to be dissipated uniformly across joints
Degenerative Articular Cartilage
Equilibrium between anabolism and catabolism is weighted in favour of degradation
Disruption of homeostasis
Increased water content
Decreased proteoglycan content
The weakening of the collagen network
Prevention
- Lose weight
- Optimize body weight
- Avoid stairs and squatting, excessive walking
Treatment
Conservative
Analgesic (pain relievers)
Cartilage supplements
Intra-articular injection
Bracing/walking aid
Surgical
Arthroscopic debridement
Partial knee replacement
Total knee replacement
Offloading Bracing
Medication
Analgesic
Simple (Panadol)
Opioids (Tramadol)
Anti-inflammation
NSAIDs (Diclofenac)
COX-2 inhibitors (Arcoxia/Celebrex)
Cartilage supplement—helps a little useful for some patients
No major side effect from supplements (compared to anti-inflammatories)
Early Intervention
- See your doctor when it’s in the early stages.
- If it’s mild: consider injections, offloading brace.
- Strong painkillers can cause side effects, damage kidney, blood pressure.
- Some patients have to use these daily, suggesting some form of long term treatment if kidney damage or stomach ulcers.
Injections
Intra-articular Injection
Steroids
Effective short term pain relief
Long term side effects
Risk of infection
Does not reverse pathology
Viscosupplementation
Safety
3 in 1 combo
Variable effects
Does not reverse pathology
Arthroscopic Debridement
- This is a minor keyhole surgery (if the patient wants to avoid major surgery). This might not be enough depending on how bad their joint is. I would ask them to come back 2-3 years to consider another surgery, 1cm incision x 2 “spring cleaning”
- Clean up damaged meniscus (if any)
- Does not reverse pathology
Partial Knee Replacement (Unicondylar)
- Replace only damaged area
- Reserved for EARLY stages of disease (deformities excluded)
- Is a “smaller surgery”
- Faster recovery
- If arthritis is severe to the point of affecting ligaments, then this is not possible anymore
Total Knee Replacement (TKR)
3R’s
- Replace damaged cartilage
- Realign so that the limb is no longer crooked
- Restore quality of life
Total Knee Replacement (TKR) Statistics:
20 yrs ago, success rates were 50-50
Now done under export, 99% success rate
Better techniques with more precision, new and better materials used, better pain management
Better technique
Computer Navigation - much like your controllers for the Nintendo Switch or Wii
Robotic Surgery - MAKOplasty (this is starting to kick off, hopefully bringing next wave of revolution for knee surgery)
This treatment uses a surgical arm with 360° movement. This half-knee surgery is done with the best confidence (optimal precision and alignment). Whereas older techniques utilize smaller cuts but with a precision problem with difficulty in seeing properly).
99% success if done under expert hands
Better pain management
Better Material
Oxinium
- Older materials are heavier
- Better lighter materials include ceramic-metal (it’s smoother so it doesn't break)
- These are longer lasting
- Hopefully can stretch the lifespan of the implant
- Ceramic also lesser chance of metal allergy
3. Gout (Excess Uric Acid)
- Presents as knee pain (affecting knee joint)
- Can be a big, painful problem
- Diet-related (Rich man's disease)
- Affects men more than women
- Big toe > knee > ankle
- Gout Tophi (Severe cases of gouty tophus: becomes a whole lump in the hand or elbow)
Consumption of a high-purine diet leads to all these uric acid crystals coming out of the joint and then you get pain and swelling.
Treatment
Prevention is best
Medication
Allopurinol
Colchicine
Surgery
Eat foods high in Purine in moderation.
