Why does the Knee Pain?

Any living tissue when stretched or stimulated beyond the limit, screams in form of pain. This is the body response to pathology.

What are the various causes?

There can be 1001 causes but can be broadly divided into Injury, Infection, Inflammation like Rheumatoid Arthritis and chronic conditions like usual wear and tear, so called Degenerative Arthritis.

What is Osteoarthritis?

Knee is the most complex joint of the body, The knee is composed of 3 bones: the femur (Thigh Bone), Tibia (Shin Bone), and Patella (Knee Cap).

Whenever you walk, sit, squat, turn around, drive or perform any other seemingly simple movement , you are depending on knee for support and mobility.

Joint is being subjected to lot of pivot and grinding movements. This causes wearing of end surfaces covered with rubber (cartilage). This eventually starts wearing off and causes decrease in cartilage thickness. This puts more stress on bone ends. Body tries to compensate by making bone harder (sclerosis) and extra bone formation (Osteophytes). Eventually this leads to deformity of knees, painful on loading. At times body try to dilute these painful irritants by making fluid (Effusion). This causes acute onset of pain and restricted movements of knee Joint.

In short, Primary Osteoarthritis is a joint Inflammation condition, results due to cartilage degeneration. It is progressive in nature, and occurs mainly in weight bearing joints like hip and knee.

When the osteoarthritis happens due to diseased or injured cartilage, its called secondary osteoarthritis.It can be caused by Injury, Infection and Diseases like Rheumatoid Arthritis, Crystal Deposition Dis, PVN synovitis etc. It Commonly leads to pain in the affected joints after repetitive use.

Osteoarthritic joints present with painful, stiff and creaking joints. Characteristic feature is rest stiffness, i.e. if you have rested beyond 10 minutes, movements are stiff and painful and strainful for few minutes till it becomes free. Gradually wasting of muscles around knee sets in and mobility starts decreasing. This sets in a viscious cycle whereby increased pain and stiffness causes more muscle wasting and loss of mobility.

How Do We Make a Diagnosis of Osteoarthritis..?

Physical attributes like middle or older age group, swelling around knee with deformity. Patient walks with a limp or extra effort or avoid walking altogether.

Examination will show deformity with decreased range of movements, creaking noise, and tender joint lines.

Confirmation is done with plain xrays of joint, front (AP) and side (Lat) views.

Kellgren-Lawrence Grading Scale

Grade 1: doubtful narrowing of joint space and possible osteophytic lipping.

Grade 2: definite osteophytes, definite narrowing of joint space

Grade 3: moderate multiple osteophytes, definite narrowing of joints space, some sclerosis and possible deformity of bone contour

Grade 4: large osteophytes, marked narrowing of joint space, severe sclerosis and definite deformity of bone contour

Grading of Disease - Osteoarthritis of Knee

There are various attempts made to grade the disease for standardization of treatment protocols.

Grading is based on three parameters: pain, loss of function and xray reading.

Its very difficult to quantify pain as different people have different thresholds. Emotional status of patient also has a influence on pain perception.

PAIN Assessment

BY Visual Analouge Scale

Functional Assessment

OXFORD (Knee Functional score)

KOOS SCORE (Knee Scoring & Osteoarthritis Outcome Score)

Treatment Guidelines for Osteoarthritis Knee

Armed with patient pain, function score and xray pics, we need to sit down with the patient and assess their requirements and limitations.

Education and Self Management Self-management strategies with the person with osteoarthritis. Ensure that positive behavioural changes, such as exercise, weight loss, use of suitable footwear and pacing, are appropriately targeted. Self-management education programmes are behavioural interventions designed to encourage people with chronic disease to take an active role in the management of their own condition. These programmes aim to improve outcomes for patients by supporting, not replacing, medical care. The content used to educate patients about their condition and to explain how they can best manage their symptoms varies between programmes.

Thermotherapy Thermotherapy involves applying heat or cold to joints to improve the symptoms of osteoarthritis and can be done with packs, towels, wax, etc. Heat may work by improving circulation and relaxing muscles, while cold may numb the pain, decrease swelling, constrict blood vessels and block nerve impulses to the joint. Thermotherapy can be used in rehabilitation programmes or at home.

Exercise and Manual therapy

Range-of-motion: To maintain normal joint movement and relieve stiffness. These make the joints flexible. Strengthening exercises to increase the strength of muscles that support the joints affected by arthritis. Aerobic or endurance exercises: They improve cardiovascular fitness, control weight and improve overall body function. Aerobic walking, strengthening of the quadriceps, resistance training and tai chi are a few examples of exercises that can be efficacious for knee OA patients.

Manual therapy is defined as the application of manual forces of the therapist, to change/improve the quality and the range of motion of joints and soft tissues. Mobilization is a manual technique that through repeated passive motion at low speed replicates normal joint glides at varying amplitudes, while manipulation is defined as fast with a small force, small amplitude and high speed of movement of a joint.

Weight loss Interventions to achieve weight loss as a core treatment for people who are obese or overweight


A) Transcutaneous Electrical Nerve Stimulation (TENS) : TENS is a method of electrical stimulation which primarily aims to provide a degree of symptomatic pain relief by exciting sensory nerves and thereby stimulating either the pain gate mechanism and/or the endogenous opioid system. Pain relief using a TENS machine with 'the pain gate' theory involves excitation of the 'A beta (Aβ) sensory fibres, and by doing so, reduces the transmission of the noxious stimulus from the ‘c’ fibres, through the spinal cord and hence on to the higher centres. The Aβ fibres appear to appreciate being stimulated at a relatively high rate (in the order of 90 - 130 Hz or pps). It is difficult to find support for the concept that there is a single frequency that works best for every patient, but this range appears to cover the majority of individuals. ''An alternative approach is to stimulate the A delta (Aδ) fibres which respond preferentially to a much lower rate of stimulation (in the order of 2 - 5 Hz), which will activate the opioid mechanisms, and provide pain relief by causing the release of an endogenous opiate (encephalin) in the spinal cord which will reduce the activation of the noxious sensory pathways.'

B) Aids and devices: Advice on appropriate footwear (including shock-absorbing properties) as part of core treatments for people with lower limb osteoarthritis

C) Oral analgesics : Should consider offering paracetamol for pain relief in addition to core treatments regular dosing may be required

D) Intra-articular injections : Intra-articular corticosteroid injections should be considered as an adjunct to core treatments for the relief of moderate to severe pain in people with osteoarthritis

B) TOTAL KNEE REPLACEMENT A total knee replacement (TKR) is a complex procedure that requires an orthopaedic surgeon to make precise measurements and skillfully remove the diseased portions of your bone, in order to shape the remaining bone to accommodate the knee implant.


When discussing the possibility of joint surgery, check that the person has been offered at least the core treatments.

Consider referral for joint surgery for people with osteoarthritis who experience joint symptoms (pain, stiffness and reduced function) that have a substantial impact on their quality of life and are refractory to non-surgical treatment.

Refer for consideration of joint surgery before there is prolonged and established functional limitation and severe pain.


Clinicians with responsibility for referring a person with osteoarthritis for consideration of joint surgery should ensure that the person has been offered at least the core (non-surgical) treatment options

Base decisions on referral thresholds on discussions between patient representatives, referring clinicians and surgeons, rather than using scoring tools for prioritisation.

Patient-specific factors (including age, sex, smoking, obesity and comorbidities) should not be barriers to referral for joint surgery.

When discussing the possibility of joint surgery, check that the person has been offered at least the core treatments for and give them information about:

  • the benefits and risks of surgery and the potential consequences of not having surgery

  • recovery and rehabilitation after surgery

  • how having a prosthesis might affect them

  • how care pathways are organised in their local area.


    Total knee replacement can increase mobility and decrease pain in people who have an injured or arthritic knee joint. More than 90 percent of patients who have knee replacement surgery experience less pain and greater mobility in their knee after the procedure.


    Cold therapy: By reducing circulation, cold therapy can help decrease swelling. For example, your physical therapist may place a cold compress on your knee joint.

    Heat therapy: Heat therapy increases blood flow to decrease stiffness in the knee joints and muscles surrounding the knee. For example, the physical therapist can place a warm heating pad on your knee joint to promote circulation.

    Hydrotherapy: Also sometimes referred to as aquatic therapy, this treatment uses water to decrease your knee osteoarthritis symptoms. There are several advantages of hydrotherapy. For example, you can do gentle exercises in the water (which won't aggravate your joints). Also, just being in warm water can help facilitate motion as well as help you deal with pain and other knee OA symptoms.

    Common Active Treatments for Knee Osteoarthritis

    Strengthening exercises: Your physical therapist will show you certain exercises that you can do at home to strengthen your muscles. Working out muscles in the leg can help make your knee joints stronger. Strengthening these muscles alone can help decrease the pain of knee OA.

    Flexibility exercises: Because knee OA often makes it hard to move, flexibility exercises are very important. Doing them regularly can help increase range of motion, make your knees more flexible, and restore normal knee joint function.