Osteoarthritis is the ‘wear and tear’ (or degenerative) type of arthritis that represents the thinning and roughening of the normally smooth cartilage that covers each side of a joint. Osteoarthritis produces pain with activity (and sometimes at rest), stiffness and reduced movement.

Osteoarthritis can be ‘primary’ and unrelated to injury or ‘secondary’ and caused by a previous injury.

There are three main patterns of secondary wrist arthritis (see sections below for further information):

• Scaphoid non-union advanced collapse (SNAC) arthritis

• Scapholunate advanced collapse (SLAC) arthritis

• Arthritis following a distal radius fracture with malunion

Wrist osteoarthritis can also sometimes occur secondary to rarer conditions like Kienböck’s disease or Madelung deformity.

The wrist is the most complex joint in the body, and is made up of eight small bones, termed carpal bones, which are bound together by ligaments. The carpal bones are named as follows: scaphoid, lunate, triquetrum, pisiform, trapezium, trapezoid, capitate and hamate. Every point of contact between the carpal bones is a joint and arthritis can occur at any or all of them. 

The eight carpal bones are aligned in two rows, which divide the wrist into two main joints: radiocarpal joint (where the carpal bones rest on the end of the radius, a forearm bone), and midcarpal joint (situated between the two rows). The majority of wrist movement originates from the radiocarpal joint, but the midcarpal joint helps with some movements like when throwing a dart.

Scaphoid non-union advanced collapse (SNAC) is a pattern of wrist osteoarthritis that can occur in the years and decades following a scaphoid fracture that did not heal following the original injury or trauma. Scaphoid fractures are the commonest type of carpal bone fracture and this injury should initially be managed with cast immobilisation or surgical fixation. If scaphoid fractures fail to heal or unite (termed non-union), the fracture fragments will move incorrectly and exert abnormal pressure and stress on the surrounding bones. This will cause wear and tear of the cartilage, which is termed SNAC (osteoarthritis).

The pattern and severity of SNAC arthritis can vary widely, ranging from small areas of wear on the thumb side of the wrist (such as between the scaphoid and radius) to arthritis that affects most of the wrist.

Up to 100% of people with scaphoid non-unions will demonstrate some degree of wrist arthritis on X-rays in the 10-20 years following injury; however, many may never experience symptoms such as pain (i.e. the condition is asymptomatic). The true incidence of symptomatic SNAC arthritis is therefore not well understood.

Scapholunate advanced collapse (SLAC) is a pattern of wrist osteoarthritis that can sometimes occur in the years and decades following an injury of the scapholunate ligament of the wrist. The scapholunate ligament is a small but important ligament that binds the scaphoid and lunate bones together. Scapholunate ligament injury can occur following a fall onto an outstretched hand or with more complex injuries like forced twisting of the hand and wrist. This injury will permit uncoordinated and abnormal movements of the scaphoid and lunate (which normally move together in sync), which can lead to abnormal pressure and stress on the surrounding joints. In some this will cause wear and tear of the cartilage, which is termed SLAC (osteoarthritis).

Not all people with scapholunate ligament injury will develop arthritis and the true incidence of SLAC arthritis is not known (as many do not seek review by a doctor).

The pattern and severity of SLAC arthritis can vary widely, ranging from small areas of wear on the thumb side of the wrist (such as between the scaphoid and radius) to arthritis that affects most of the wrist. It should be noted that some people with arthritic changes on X-rays may never experience symptoms such as pain (i.e. the condition is asymptomatic).

Wrist arthritis can also develop following fractures of the distal radius (wrist) that have healed with a step or gap in the normally smooth cartilage surface of the wrist joint (termed distal radius malunion). Only distal radius fractures that enter the wrist joint and interrupt the cartilage surface (termed intraarticular) are at risk of developing wrist arthritis in the future. Many distal radius fractures do not involve the joint surface (termed extraarticular) and are therefore not usually associated with wrist arthritis. The radiocarpal joint of the wrist is the area that is most commonly affected by this type of wrist arthritis.

It should be noted that many people with arthritic changes on X-rays following distal radius malunion will never experience pain or symptoms (i.e. the condition is asymptomatic).

Some of the potential symptoms of wrist osteoarthritis are listed below. Many people with arthritic changes on X-rays will have no or minimal symptoms. Symptoms may flare after a minor injury or heavy activity and symptoms following this ‘flare up’ will commonly settle with time.

Typically present:

• Pain in the wrist.

• Pain that worsens with activity, such as gripping and lifting.

• Tenderness at the site of pain.

Sometimes present:

• Weakness of grip (usually due to pain).

• Swelling at the site of pain.

• Stiffness with reduced wrist movements.

• Grinding or scratching feelings at the site of pain.

It is important to correctly diagnose wrist osteoarthritis (due to SNAC, SLAC and distal radius malunion) and exclude other causes of wrist pain, such as thumb base arthritis, distal radioulnar joint (DRUJ) arthritis, pisotriquetral arthritis, ulnocarpal abutment syndrome, tendon inflammation (e.g. De Quervain’s syndrome, extensor carpi ulnaris tendonitis), triangular fibrocartilage complex (TFCC) tears, ganglion cysts or Kienböck’s disease.

The diagnosis is usually made on the history (your symptoms), clinical examination and X-rays. Sometimes an MRI or CT scan or wrist arthroscopy (‘keyhole’ surgical assessment) is recommended.

A blood test may be recommended if an inflammatory type of arthritis is suspected.

In most cases, the treatment for wrist arthritis (due to SNAC, SLAC and distal radius malunion) is non-surgical, and most people will never require surgery for this condition.

Non-surgical treatment options include simple painkillers, avoidance of painful activities, wrist splintage and physiotherapy (mostly functional advice and splintage). It may take weeks or months to notice a gradual improvement and return to function. A steroid injection (e.g. cortisone) can be an effective treatment; however, the pain-relieving effect will differ between individuals and will usually wear off with time (a good and common response would be 3-6 months of improved pain).

Surgical treatment options include wrist arthroscopy (‘keyhole’ surgery), denervation, bony excision, proximal row carpectomy, partial wrist fusions, total wrist fusion and joint replacement.

There are many surgical options for wrist arthritis and decision-making is based on a combination of your symptoms (including pain location and wrist range of movement) and the pattern of wrist arthritis (i.e. the areas affected). Not all patterns of wrist arthritis will be suitable for each treatment option. Keyhole surgical assessment (arthroscopy) is sometimes helpful when assessing the extent of joint damage, for example when X-rays or scans are unclear. 

• Wrist arthroscopy is a minimally-invasive or ‘keyhole’ surgical technique that can assess the inside of your wrist joint with a narrow camera. Arthroscopy can also permit removal of inflamed soft tissues or loose cartilage (termed debridement), excision of bone spurs or small areas of arthritis (such as excision of the radial styloid), and help when planning future treatments.

• Radial styloidectomy removes the styloid (the tip of the radius bone) when arthritis is isolated to this area (it can be performed using minimally-invasive ‘keyhole’ or open surgery).

• Denervation involves cutting and interrupting the small nerves that deliver feelings of pain from the wrist. Although denervation helps to preserve wrist movement, the degree of pain relief from this surgery can be difficult to predict and any benefit will often wear off with time. 

• Proximal row carpectomy (PRC) removes the arthritic joint surfaces by removing three bones from the wrist (scaphoid, lunate and triquetrum). 

• Partial (or limited) wrist fusions include the so-called ‘four corner’ or column fusions, which aim to fuse (and remove) the arthritic joint surfaces (this operation also includes removal of the arthritic scaphoid bone). 

• Total wrist fusion is reserved for more advanced patterns of wrist arthritis.

• Total wrist replacement may be suitable for a very small minority with advanced patterns of wrist arthritis.

PRC and partial wrist fusions often preserve some wrist movement (but significant stiffening is still common), whilst total wrist fusion will remove all wrist movement but preserve forearm rotation.

Matthew offers all of the above treatments. Matthew does not perform wrist replacement in the private sector.

Surgery for wrist arthritis is usually performed under general or regional anaesthesia. Click here for an overview of the different types of anaesthesia and the general risks of hand surgery. The additional and specific risks associated with surgery for wrist arthritis will be discussed if surgery is an option, but includes continuing or new pain and stiffness.

You can read more detailed information regarding wrist arthritis on the Lothian Hand Unit website.