Shoulder Anatomy & Function
The shoulder is the most mobile joints in the body, made of three bones: the upper arm bone (the humerus), the shoulder blade (the scapula) and the collarbone (the clavicle). There are two joints in the shoulder. Both joints can become arthritic. Some also consider the scapula thoracic area a joint.
- The ball and socket joint, called the glenohumeral joint, is made of the head of the humerus and fits into the socket called glenoid, part of the shoulder blade. The joint is held together by a network of soft tissue including muscles, ligaments, and tendons that work together to provide a wide range of motion, and joint stability.
- The other shoulder joint is called the acromioclavicular (AC) joint, made of the clavicle that meets the tip of the shoulder called the acromion.
Arthritis of the shoulder is joint inflammation that causes pain and joint stiffness. There are several types of arthritis that affect the shoulder joint, but osteoarthritis of the glenohumeral joint is the most common type. It is characterized by the erosion of articular cartilage that lines the surface of the bones which results in the bones rubbing together. This causes pain, impairs motion and may create bone spurs.
Osteoarthritis (OA) is the leading cause of shoulder pain and disability in people over the age of 50. However, younger people who suffer a trauma or injury to the shoulder can develop post- traumatic OA. The goal of treatment is to relieve pain and improve function.
What are the symptoms of osteoarthritis?
The main symptoms are joint pain that is aggravated with use, joint tenderness and a reduced range of motion. The location of the pain is an indication of the location.
- When the glenohumeral joint is affected the pain is in the back of the shoulder. Changes in the weather can intensify the pain. The chief complaint is a deep ache in the joint.
- When the acromioclavicular joint is affected the pain is on the top of the shoulder and can radiate down the side of the neck. People with AC joint arthritis are at risk for rotator cuff tears.
- Rheumatoid arthritis causes pain in both joints. Whereas OA can affect one or both shoulders.
- When range of motion is limited, it affects the ability to execute normal daily activities like combing your hair or reaching overhead.
- As the disease progresses the joint may make grinding, clicking or snapping sounds with movement. Any movement can cause pain and pain at night can disrupt sleep.
How is arthritis diagnosed?
Your Orthopedic Associates of Northern California (OANC) doctor will review your medical history and conduct a physical examination. They will perform certain tests to evaluate your range of motion, signs of soft tissue damage, and location of pain. A blood test may be ordered to rule out rheumatoid arthritis. X-rays will be ordered to confirm the diagnosis and reveal bone spurs, cysts and reduced joint spaces. Special imaging tests may be ordered to rule out other conditions and to evaluate the rotator cuff.
How is it treated?
Treatment depends on the severity of symptoms and the degree of disability. Conservative management includes rest, ice and heat therapy, activity modification, anti-inflammatory medications, exercises/physical therapy, and possibly steroid injections. Your OANC doctor may recommend the use of the dietary supplements such as glucosamine and chondroitin sulfate to relieve pain.
When conservative measures do not relieve symptoms, surgery may be considered. Surgical procedures for OA include:
- Shoulder arthroscopy, a minimally invasive procedure to view the joint and clean out the frayed cartilage. It is designed for pain relief. It doesn’t treat the OA.
- A partial or total joint replacement (arthroplasty). A partial joint replacement involves replacement of the head of the upper arm bone. A total shoulder arthroplasty involves replacement of the entire shoulder joint.
Orthopedic Associates of Northern California (OANC.org) has been providing quality patient care since 1995 at its offices in Chico, California. Our team of board-certified orthopedic surgeons offers advanced surgical and preventive procedures and techniques to address all of your orthopedic needs.
Contact OANC to schedule a consultation and receive the quality care you deserve so you can live comfortably and enjoy your life.