- Definition- Osteoarthritis is a misnomer, as it is not an inflammatory disease.
- Instead, ideal name is Osteoarthrosis as it is a degenerative condition.
- It can be defined as a degenerative disorder of Articular cartilage & Bone in Knee Joint.
- It can be understood as a ‘joint failure’ wherein there is an imbalance of mechanical strength versus mechanical stress imposed on Articular Cartilage & Bone. (As osteo means bone & Arthros means joint).
What is degeneration
Is a process of cellular changes in response to trouble leading to decrease in its efficiency.
- Trouble can be trauma, temperature, chemical, infection, age. Many things.
- The changes observed are biochemical, cellular hence microscopic, gross & with aftereffects.
- Structure of Articular Cartilage- It is Hyaline cartilage made up of chondrocytes & Extracellular matrix (ECM). ECM is made up of proteoglycans- responsible for compressive stiffness & Collagene fibers which resist shear. The average thickness of cartilage is about 5-7mm
- It serves two functions- first is to provide ultra-smooth articulating surface & second is weight bearing & distribution.
- It is devoid of nerve endings, hence even if damaged no pain signal is sent.
- It does not have blood vessels in it, hence depends on synovial fluid & periosteal blood vessels for nutrition.
- It has less cellular components.
- Both above factors lead to a slow process of regeneration.
- The degenerative process occurring in articular cartilage is either due to excessive loading or its & underlying bone’s (Subchondral bone)inferior quality.
- Although articular cartilage is highly resistant to wear, repeated oscillations & repetitive impact loading soon leads to joint failure.
Effects of Degeneration
- Articular Cartilage- Softening, disruption of smooth surface, fibrillation, Abrasion- cleft formation fragmentation, repair by fibrocartilage & fibrous tissue.
- Bone- fibrosis/sclerosis, cyst formation, exophytic growth at margins of articular cartilage called Osteophytes.
Effects on knee Joint
- Decrease in joint space
- Capsular deformation giving rise to pain signal.
- Ligamental laxity leading to varus deformity.
- Reflex inhibition of Quadriceps due to pain signal.
- Knee joint adapts minimal flexion position to reduce pain signals (fixed flexion) which is due to contraction of hamstring muscles & gastrocnemius.
- Why in Knee Joint?
- Weight bearing joint
- Most used joint
- Incongruous joint
Radiographic grading of OA knee
The kellgren and Lawrence system is a common method of classifying the severity of knee osteoarthritis using five grades. This classification was proposed by kellgren in 1957 and lateral accepted by WHO in 1961. In applying the system, the prevalence of chronic knee pain in a postal survey of 2000 Swedes aged 35-54 was 15%. Of these respondents, 1% showed
radiographic knee OA based on bilateral weight bearing plain films. Classification
- Grade 0- no radiographic features of OA are present.
- Grade 1- doubtful joint space narrowing (JSN) and possible osteophytic lipping
- Grade 2- definite osteophytes and possible JSN on Antero posterior weight-bearing radiograph
- Grade 3- multiple osteophytes and definite JSN, sclerosis, possible bony deformity.
- Grade 4- Large osteophytes, marked JSN, severe sclerosis, definite bony deformity.
Concepts of Medical Yoga Therapy
5R
- Resolve -To understand cause and its effects
- Reverse - Try to minimize the cause
- Restore - To normalcy or near- normalcy
- Rejuvenate - The concerned tissue (To make it lively or youthful)
- Regeneration - Of the concerned tissue