Arthroscopy may be used to confirm diagnosis of or treat a large number of conditions, including acute trauma to soft tissues. These may be removed, repaired or reconstructed. Examples of such injuries, which often occur during sports, include:

• Rotator cuff injuries. Injury to muscles and tendons that connect the upper arm bone (humerus) to the shoulder blade (scapula). Arthroscopic surgeons can complete tasks such as repairing tears or performing acromioplasty, which involves shaving bone from a point (acromion) on the scapula.
  
  
• Anterior cruciate ligament (ACL) tears. A complete tear requires extensive rehabilitation to restore function and ease knee pain.
  
  
• Meniscus injury. Injury to the cartilage disc (meniscus) between the two surfaces of a joint. These are often allowed to heal naturally. However, arthroscopy may be used to repair these injuries if the tear is complex or the symptoms occur daily. Also, it may be completed if general function is hindered or if leaving the injury unrepaired may cause further damage.
  
  
• Achilles tendon injuries. Arthroscopy may be used in treating tears to the Achilles tendon, a common cause of foot pain.

Other conditions in which arthroscopy may used include::

• Rheumatoid arthritis. A chronic, inflammatory form of arthritis. Affected portions of the synovium (fluid sac lubricating the joints) may be removed with arthroscopic assistance.
  
  
• Infectious arthritis. Arthritis caused by infection. Arthroscopy may be used to wash out the joint. This may provide minor, temporary relief.
  
  
• Osteoarthritis (OA). Degenerative bone arthritis. The use of arthroscopy in the treatment of OA is controversial. Some studies suggest that it provides little or no more benefit than a placebo. However, arthroscopy may be used to smooth off the roughened edges of bone. This is widely done in the knee. It may offer temporary relief of symptoms and may slow down the arthritic process, but it cannot stop the disease.

• Chondromalacia. Softening or degeneration of the cartilage in the joint. This may be identified with arthroscopy. If it is not extensive, it can be treated with arthroscopy, but extensive chondromalacia may require other treatment methods.
  
  
• Patellofemoral syndrome (runner’s knee). Arthroscopic shaving of the patella (kneecap) is sometimes recommended to address difficult cases of this overuse injury, a common cause of knee pain.
  
  
• Articular debris. Loose fragments of bone or cartilage in the joint. These may be identified and removed with arthroscopy.
  
  
• Carpal tunnel syndrome. Compression of the median nerve in the wrist. An arthroscopic technique called endoscopic carpal tunnel release (ECTR) has in recent years become a popular alternative, when appropriate, to traditional open carpal tunnel release surgery.

• Tennis elbow (lateral epicondylitis) or golfer elbow (lateral epicondylitis). Types of repetitive stress injury that affect tendons and muscles in the elbow. Arthroscopic surgery can removed damage tissues and release tendons to relieve these causes of elbow and arm pain.
  
  
• Hemarthrosis. Accumulation of blood in the joint. The blood can be drained during arthroscopy.
  
  
• Mechanical dysfunction. This may include the abnormal alignment or instability of the joint. Arthroscopy may be used to correct this.
  
  
• Osteophytes (bone spurs). These may be removed via arthroscopy.
  
  
• Fractures. Sometimes arthroscopy is used to determine whether surgery is needed for a broken bone, such as in the glenohumeral region of the shoulder.

• Torn labrum. Damage to the cartilage rim of the socket-like acetabulum in the hip. In some cases, arthroscopic repair of a torn labrum may prevent degeneration of the hip and avert or delay the need for a hip joint replacement (arthroplasty).
  
  
• Synovitis. Inflammation of the synovium. Synovectomy (removal of the synovium) may be performed with arthroscopic assistance.
  
  
• Osteomyelitis or other joint infections. Joint tissue biopsies may be collected and some instances of infection treated during arthroscopy.
  
  
• Radial tunnel syndrome. Impingement of the radial nerve in the elbow. Symptoms are similar to those of tennis elbow. Arthroscopy may be recommended if conservative treatments such as occupational therapy fail.
  
  
• Gout or pseudogout. Arthroscopy may be used to examine crystal formations in these arthritic conditions.
  
  
• Frozen shoulder (adhesive capsulitis). Arthroscopy might be an option if noninvasive methods fail to stretch the capsule, increase range of motion and ease shoulder pain.