Four Stages of Osteoarthritis of the Hip

Hip osteoarthritis is a progressive disease in which the hip joints experience adverse changes to cartilage and bone and gradually deteriorate over time. These changes develop in four distinct stages:

• Stage 1: This is the earliest stage in which wear and tear of the hip joint may cause bone spurs but typically no pain.
• Stage 2: This is when joint cartilage starts to break down, but the space between joints is still normal. Occasional stiffness or pain is common.
• Stage 3: This is when the erosion of cartilage narrows the joint space, making everyday movements like walking or squatting painful or difficult
• Stage 4: This is the most advanced stage in which the loss of cartilage and joint lubrication causes bone to rub on bone, resulting in chronic pain, stiffness, and loss of mobility.

This article describes the four stages of hip osteoarthritis in detail, including the symptoms and treatment options of each stage.

Stage 1 Hip Osteoarthritis

This is the earliest and mildest stage of hip osteoarthritis (OA). During stage 1, there are few signs of wear-and-tear between the hip joints, with the exception of tiny bone spurs known as osteophytes.

Osteophytes are irregular bone growths caused by inflammation in deteriorating joints. As part of the inflammatory response, a protein called transforming growth factor-beta (TGF-β) causes bone minerals to clump together irregularly.

Symptoms

Stage 1 hip OA is largely asymptomatic (without symptoms) and causes little to no pain. For this reason, people with stage 1 hip OA may not be aware that they even have the disease.

Treatments

Prevention is the main focus of treatment for stage 1 hip OA. This may involve avoiding activities that aggravate the affected joint, such as strenuous running. People with stage 1 hip OA may need to modify their exercise routine to minimize stress on the hips, such as avoiding squats with heavy weights.

If you are overweight, weight loss can reduce the amount of stress placed on the hip joints and help slow the progression of the disease. 

Supplements like glucosamine and chondroitin may be prescribed. While the evidence supporting these supplements is conflicted, they are generally regarded as safe.

Stage 2 Hip Osteoarthritis

Stage 2 hip OA is commonly referred to as mild hip osteoarthritis. Bone spur growths may be seen on X-rays, but the space between the bones will still appear normal.

Although joint cartilage remains healthy at this stage, there will be a due to breakdown due to an increased production of enzymes called metalloproteinases. 

Symptoms

People with stage 2 hip OA will start to experience:

• Pain and discomfort in the hip joint, typically on one side only
• Aching or weakness in the joint after strenuous activity
• Joint stiffness, especially in the morning or after sitting for a long time

Treatments

People with OA stage 2 hip are usually placed on a regular exercise plan with strength-building exercises. Strengthening the muscles around the joints can help stabilize the hips and keep them strong.

Knee braces may be used if you also have knee osteoarthritis. If the knee is destabilized, it can affect the position of the hip and make hip OA symptoms worse.

Stage 3 Hip Osteoarthritis

Often referred to as moderate hip osteoarthritis, stage 3 hip OA is characterized by the significant erosion of the cartilage between the bones of the hip joint. As the gap between the bones narrows, joint inflammation will increase and promote the growth of osteophytes.

At the same time, collagen fragments from deteriorating cartilage will be released into the lubricating fluid around joints (called synovial fluid), altering its viscosity (slickness) while further increasing joint inflammation,

Symptoms

People with stage 3 hip osteoarthritis will experience:

• Hip pain with normal activities like walking, running, squatting, or kneeling
• Joint swelling with prolonged activity or standing
• Joint stiffness in the morning or after sitting a long time
• Popping, grating, or snapping sounds as the hip joint moves
• A "catching" sensation as the hip joint moves
• An uneven gait or limping
• Increasing hip weakness

Treatments

People with moderate hip arthritis should continue the lifestyle strategies recommended in stages 1 and 2.

Over-the-counter painkillers like Tylenol (acetaminophen) or non-steroidal anti-inflammatory drugs (NSAIDs) such as Advil (ibuprofen) are usually recommended. If these treatments don't help, your healthcare provider may prescribe a stronger NSAID like Celebrex (celecoxib).

Physical therapy may be recommended to strengthen the muscles around the joints and improve your mobility. Healthcare providers may also give corticosteroid (steroid) injections into the joint space to decrease inflammation and deliver longer-term pain relief.

Stage 4 Hip Osteoarthritis

Stage 4 hip OA is also known as advanced hip osteoarthritis. At this stage, the joint cartilage has thinned and is extremely brittle, while chronic joint inflammation has contributed to the formation of large osteophytes and the loss of synovial fluid.

Stage 4 hip OA suggests that bone is rubbing on bone and the function of the joint has been compromised.

Symptoms

With stage 4 hip OA, symptoms tend to be severe and commonly include:

• Constant joint pain and stiffness even without activity or movement
  
• A significant loss in the range of motion of the hip
• Hip weakness or a sense that the hip may collapse under you
• Pain in the opposite hip as it is forced to compensate for the affected hip
• Muscle thinning in the legs due to the loss of mobility
• Disruption of sleep due to pain
• An increased risk of falling

Treatments

Surgery is often delayed with treatments like hyaluronic acid injections that aim to improve joint lubrication. Repeated steroid injections or oral opioid painkillers may be offered. Assistive walking devices, such as a cane, crutches, walker, or wheelchair, may be offered.

If surgery is recommended, it may include:

• Bone realignment surgery: During this procedure, bone is removed from around the affected joint so that the joint can be aligned into a more stable, mobile position. This surgery is typically an option for people under 60.
• Total hip replacement: Also known as total hip arthroscopy (THA), this is a procedure in which the damaged hip joint is removed and replaced with a prosthetic device. Recovery may take several weeks and involves physical and occupational therapy.