Osteoarthritis - A degenerative pathology of the human cartilage

Osteoarthritis is a degenerative process, an age- and stress-related change or wear and tear of our joints, which begins with local cartilage damage and progresses over time. One or more joints can be involved.

Origin & Development

Osteoarthritis is due to an imbalance between the resilience and strain of our joints, which eventually results in cartilage degradation. Besides, joint capsule changes, bone lesions, and inflammation can occur.

In adults, the articular cartilage has no blood supply and feeds exclusively by diffusion from the joint fluid (synovia), which contains all essential nutrients. It consists of more than 90% water and contains hyaluronic acid, proteins, glucose, and so-called glycosaminoglycans, which are characterized by a high water-binding capacity.

However, adequate joint lubrication is decisively dependent on sufficient and well-dosed movement. After the completion of the growth phase, cartilage cells have only a very low capability of dividing. Therefore articular cartilage once damaged in adults is only partially regenerating or irreparable in the advanced stage.

Causes of osteoarthritis

• Congenital joint deformities with resulting mechanical overload of the joints

• Load on structurally damaged joints (due to dislocations, fractures, circulatory and nutritional disorders, inflammation, toxins, metabolic and hormonal diseases, disorders of the immune system)

• Unphysiological stress on joints due to work and sports

• Genetically inherited weakness of joint structures

• Insufficient lubrication of the joints due to lack of movement

• Overweight

• Idiopathic factors (unknown causes)

Pathophysiology

Mechanical cartilage damage increases friction and reduces shock absorption within the joint. As a result, inflammation of the joint capsule (synovitis) or other joint structures such as the bone (osteoarthritis) often occurs.

The disadvantage is that the mechanical damage to the joint structures causes certain enzymes (so-called lysosomal enzymes) to be released from the cartilage cells, which additionally attack and destroy the cartilage, and consequently create a vicious circle.

Prognosis

The process of cartilage damage progresses rather slowly, but sometimes also deteriorates in a relapse. A cure is not possible, but it can be slowed down by appropriate therapy measures and targeted training under physiotherapeutic guidance.

Localization

The spine is most often affected by osteoarthritis. It is then called spondylarthrosis. This is followed by the knee joint (gonarthrosis), hip joint (coxarthrosis), and shoulder joint (glenohumeral arthritis). In the area of the hand, osteoarthritis of the thumb (basal joint arthritis) is most common. Other joints are less likely to be arthritically altered.

Remarkable is the fact that the present symptoms and the results of the imaging procedures (MRI, X-rays, scintigraphy, ultrasound) often do not result in a coherent picture. For example, based on an X-ray finding, it is not possible to draw clear conclusions about the severity of the symptoms.

Symptoms

Osteoarthritis is divided into different stages (Stage I-III), each showing specific symptoms.

Stage I

• Increasing instability of the affected joint

• Pain during stress and fatigue

• Muscle tension

• Decrease in mobility

• Changed movement behavior

Stage II

• Pain during unloaded or passive movements

• Pain at the beginning of a movement, which decreases or disappears the more the affected joint moves

• Cold-related pain

• Joint capsule contractures

• Decrease in strength

Stage III

• Joint inflammation with tissue swelling

• Heavy morning stiffness

• Rest, long-term, and night pain (typical inflammatory pain)

• Reinforced joint contractures up to deformed and stiff joints in the final stage

Physiotherapy (Objectives and measures)

Pain relief

• Heat applications, analgesic electrotherapy

• Pain-relieving positions

• Manual therapy (intermittent traction)

• Reduction of muscle tension through functional massage, inhibitory pain mechanisms in painful tendon attachments like trigger point treatment

Improving cartilage nutrition

• See: pain relief

• Treatment techniques with adequate compression of the joint to stimulate the metabolism and nutrition of cartilage cells

• Active exercises with a partial or full load, if the pain doesn’t require relief

Maintaining and improving mobility

• Manual therapy (traction and glide mobilizations in the affected joint)

• Muscle-energy techniques (MET), in which – based on neurophysiological principles – muscle relaxation is achieved, which in turn contributes to a facilitated improvement of joint mobility

• Movement with the largest possible amplitude and lowest possible load

Maintaining strength

• Strength and strength endurance training (functional training under partial or full load)

• Co-contraction of antagonistic (opponent) muscles surrounding the joint

Developing ergonomic movement patterns

• Manual therapy (traction and glide mobilizations in the affected joint)

• Stabilization of the adjacent joints

• Exercises under avoidance of long levers on the joints

• Possible use and training for the use of orthopedic aids (prosthesis, corsets, shoe inserts, orthopedic shoes, walking aids)

Recommendations & Health Tips

• Lifestyle changes towards a more plant-based, immune-boosting, and anti-inflammatory nutrition

• Weight reduction

• Avoidance of sports with high joint loads

• Preference for sports with lower joint loads (like swimming, cycling, or walking) to promote joint mobilization

• Avoidance of wetness and cold

Medical care and treatment

Medication

• Nonsteroidal anti-inflammatory drugs (NSAIDs), like diclofenac, ibuprofen, or aspirin, to reduce pain and inflammation

• Intraarticular injections with cortisone have anti-inflammatory effects and are more likely to be indicated in acute synovitis (inflammation of the inner layer of the joint capsule)

• Local anesthetics

• Muscle relaxants to reduce muscle tension-related pain

• Chondroprotective agents, which are supposed to stimulate the synthesis of collagen, proteoglycans, and hyaluronic acid to protect and build up the cartilage (they have no assured effect!)

Surgical Therapy

• Debridement (smoothing of the damaged cartilage and removal of destroyed cartilage particles)

• Subchondral drilling of the bone layer located below the cartilage so that vessels and connective tissue cells enter the area and form a (mostly inferior) replacement tissue

• Removal of the inner layer of the joint capsule (synovectomy) to reduce inflammation

• Osteotomy (the bone is cut and reshaped to correct ist alignment)

• Joint replacement (endoprosthesis). It shows clinical success on hips, knees, and shoulders. Ist limited durability of 10-20 years for hip joints and 5-10 years for knee joints is detrimental, which means that the joint replacement is not repeatable as often as desired and should be avoided in younger patients

• Artificial joint ossification between two bones (arthrodesis; ankylosis). It is applied to relieve intractable pain in a joint, only when conservative and surgical measures fail.