Wrist osteoarthritis is a group of mechanical abnormalities resulting in joint destruction, which can occur in the wrist. These abnormalities include degeneration of

cartilage Cartilage is a resilient and smooth type of connective tissue. In tetrapods, it covers and protects the ends of long bones at the joints as articular cartilage, and is a structural component of many body parts including the rib cage, the neck ...

and

hypertrophic Hypertrophy is the increase in the volume of an organ or tissue due to the enlargement of its component cells. It is distinguished from hyperplasia, in which the cells remain approximately the same size but increase in number.Updated by Linda J. ...

bone changes, which can lead to pain, swelling and loss of function. Osteoarthritis of the wrist is one of the most common conditions seen by hand surgeons. Osteoarthritis of the wrist can be

idiopathic An idiopathic disease is any disease with an unknown cause or mechanism of apparent spontaneous origin. From Greek ἴδιος ''idios'' "one's own" and πάθος ''pathos'' "suffering", ''idiopathy'' means approximately "a disease of its own kin ...

, but it is mostly seen as a post-traumatic condition. There are different types of post-traumatic osteoarthritis. Scapholunate advanced collapse (

SLAC SLAC National Accelerator Laboratory, originally named the Stanford Linear Accelerator Center, is a United States Department of Energy National Laboratory operated by Stanford University under the programmatic direction of the U.S. Departme ...

) is the most common form, followed by scaphoid non-union advanced collapse (SNAC). Other post-traumatic causes such as

intra-articular A joint or articulation (or articular surface) is the connection made between bones, ossicles, or other hard structures in the body which link an animal's skeletal system into a functional whole.Saladin, Ken. Anatomy & Physiology. 7th ed. McGraw- ...

fractures Fracture is the separation of an object or material into two or more pieces under the action of stress. The fracture of a solid usually occurs due to the development of certain displacement discontinuity surfaces within the solid. If a displ ...

of the distal

radius In classical geometry, a radius (plural, : radii) of a circle or sphere is any of the line segments from its Centre (geometry), center to its perimeter, and in more modern usage, it is also their length. The name comes from the latin ''radius'', ...

ulna The ulna (''pl''. ulnae or ulnas) is a long bone found in the forearm that stretches from the elbow to the smallest finger, and when in anatomical position, is found on the medial side of the forearm. That is, the ulna is on the same side of t ...

can also lead to wrist osteoarthritis, but are less common.

Types

SLAC and SNAC are two patterns of wrist osteoarthritis, following predictable patterns depending on the type of underlying injury. SLAC is caused by scapholunate ligament rupture, and SNAC is caused by a

scaphoid fracture A scaphoid fracture is a break of the scaphoid bone in the wrist. Symptoms generally includes pain at the base of the thumb which is worse with use of the hand. The anatomic snuffbox is generally tender and swelling may occur. Complications may ...

which does not heal and because of that will develop in a

non-union Nonunion is permanent failure of healing following a broken bone unless intervention (such as surgery) is performed. A fracture with nonunion generally forms a structural resemblance to a fibrous joint, and is therefore often called a "false jo ...

fracture. SLAC is more common than SNAC; 55% of the patients with wrist osteoarthritis has a SLAC wrist.

SLAC

Scapholunate advanced collapse (SLAC) is a predictable pattern of wrist osteoarthritis that results from untreated long-standing scapholunate instability, which in turn is secondary to a rupture of the scapholunate ligament. The main type of such misalignment is

dorsal intercalated segment instability Dorsal intercalated segment instability (DISI) is a deformity of the wrist where the lunate bone angulates to the dorsal side of the hand. Causes The main causes of DISI are: *Wrist trauma, with or without a fracture **Scaphoid fracture: bony DISI ...

(DISI) which is where the lunate angulates to the posterior side of the hand.

SNAC

Scaphoid

fractures changes scaphoid bone shape, which leads to abnormal joint kinematics. Due to lack of stability from the distorted scaphoid, a DISI can be developed. Scaphoid Non-union Advanced collapse (SNAC) is the pattern of osteoarthritis that eventually develops by this process.

Stages

Post-traumatic osteoarthritis can be classified into four stages. These stages are similar between SLAC and SNAC wrists. Each stage has a different treatment. * Stage I: the osteoarthritis is only localized in the distal scaphoid and radial styloid. * Stage II: the osteoarthritis is localized in the entire radioscaphoid joint. * Stage III: the osteoarthritis is localized in the entire radioscaphoid joint with involvement of the capitolunate joint. * Stage IV: the osteoarthritis is located in the entire radiocarpal joint and in the intercarpal joints. It also may involve the distal radio-ulnar joint (DRUJ). Image:Stadium1osteoarthritis.JPG, Stage I Image:Stadium2osteoarthritis.JPG, Stage II Image:Stadium3osteoathritis.JPG, Stage III Image:Stadium4osteoarhtritis.JPG, Stage IV

Signs and symptoms

The most common initial symptom of wrist osteoarthritis is

joint pain Arthralgia (from Greek ''arthro-'', joint + ''-algos'', pain) literally means ''joint pain''. Specifically, arthralgia is a symptom of injury, infection, illness (in particular arthritis), or an allergic reaction to medication. According to MeSH, ...

. The pain is brought on by activity and increases when there is activity after resting. Other signs and symptoms, as with any joint affected by osteoarthritis, include: *

Morning stiffness Joint stiffness may be either the symptom of pain on moving a joint, the symptom of loss of range of motion or the physical sign of reduced range of motion. * Pain on movement is commonly caused by osteoarthritis, often in quite minor degrees, an ...

, which usually lasts less than 30 minutes. This is also present in patients with

rheumatoid arthritis Rheumatoid arthritis (RA) is a long-term autoimmune disorder that primarily affects joints. It typically results in warm, swollen, and painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and hands are inv ...

, but in those patients this typically lasts for more than 45 minutes. * Swelling of the wrist. *

Crepitus Crepitus is "a grating sound or sensation produced by friction between bone and cartilage or the fractured parts of a bone". Various types of crepitus that can be heard in joint pathologies are: *Bone crepitus: This can be heard when two fragme ...

(crackling), which is felt when the hand is moved passively. * Joint locking, where the joint is fixed in an extended position. * Joint instability. These symptoms can lead to loss of function and less daily activity.

Mechanism

In order to understand the cause of post-traumatic wrist osteoarthritis it is important to know and understand the anatomy of the wrist. The hand is subdivided into three parts: *

Wrist In human anatomy, the wrist is variously defined as (1) the carpus or carpal bones, the complex of eight bones forming the proximal skeletal segment of the hand; "The wrist contains eight bones, roughly aligned in two rows, known as the carp ...

Metacarpus In human anatomy, the metacarpal bones or metacarpus form the intermediate part of the skeletal hand located between the phalanges of the fingers and the carpal bones of the wrist, which forms the connection to the forearm. The metacarpal bones ...

* Digits The wrist consists of eight small

carpal bones The carpal bones are the eight small bones that make up the wrist (or carpus) that connects the hand to the forearm. The term "carpus" is derived from the Latin carpus and the Greek καρπός (karpós), meaning "wrist". In human anatomy, t ...

. Each of these carpal bones has a different size and shape. They contribute towards the stability of the wrist and are ranked in two rows, each consisting of four bones.

Proximal row

From

lateral Lateral is a geometric term of location which may refer to: Healthcare *Lateral (anatomy), an anatomical direction * Lateral cricoarytenoid muscle * Lateral release (surgery), a surgical procedure on the side of a kneecap Phonetics *Lateral co ...

to medial and when viewed from

anterior Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. Th ...

, the

proximal Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position ...

row is formed by the: *

Scaphoid The scaphoid bone is one of the carpal bones of the wrist. It is situated between the hand and forearm on the thumb side of the wrist (also called the lateral or radial side). It forms the radial border of the carpal tunnel. The scaphoid bone i ...

Lunate Lunate is a crescent or moon-shaped microlith. In the specialized terminology of lithic reduction, a lunate flake is a small, crescent-shaped flake removed from a stone tool during the process of pressure flaking. In the Natufian period, a lu ...

* Triquetral *

Pisiform The pisiform bone ( or ), also spelled pisiforme (from the Latin ''pisifomis'', pea-shaped), is a small knobbly, sesamoid bone that is found in the wrist. It forms the ulnar border of the carpal tunnel. Structure The pisiform is a sesamoid bone, ...

Distal row

From

to medial and when viewed from

, the

distal Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position pro ...

row is formed by the: * Trapezium *

Trapezoid A quadrilateral with at least one pair of parallel sides is called a trapezoid () in American and Canadian English. In British and other forms of English, it is called a trapezium (). A trapezoid is necessarily a convex quadrilateral in Eu ...

Capitate The capitate bone is a bone in the human wrist found in the center of the carpal bone region, located at the distal end of the radius and ulna bones. It articulates with the third metacarpal bone (the middle finger) and forms the third carpomet ...

Hamate The hamate bone (from Latin hamatus, "hooked"), or unciform bone (from Latin ''uncus'', "hook"), Latin os hamatum and occasionally abbreviated as just hamatum, is a bone in the human wrist readily distinguishable by its wedge shape and a hook-l ...

Diagnosis

Osteoarthritis of the wrist is predominantly a clinical diagnosis, and thus is primarily based on the patients medical history, physical examination and wrist X-rays.

Medical history

Medical history of the patient should include age, hand dominance, occupation and most important an evaluation of recent hand traumas.

Physical examination

Examination will often show tenderness at the radioscaphoid joint (when palpated or while moving the radioscaphoid joint), dorsal radial swelling and instability of the wrist joint. Notice that people may say they have trouble with rising from a chair when pressure is exerted on the hands by pushing against the handrail. Younger people may complain about not being able to do push-ups anymore because of a painful hand.
There are a number of tests and actions that can be performed when a patient is suspected of having osteoarthritis caused by SLAC or SNAC. SLAC: * Tenderness 1 cm above Lister’s tubercle Tests: *

Watson's test Watson's test, also known as the scaphoid shift test, is a diagnostic test for instability between the scaphoid and lunate bones of the wrist. Test procedure To perform the test, the examiner grasps the wrist with their thumb over the scaphoid tu ...

* Finger extension test SNAC: * Tenderness at the anatomical snuff box * Painful

pronation Motion, the process of movement, is described using specific anatomical terms. Motion includes movement of organs, joints, limbs, and specific sections of the body. The terminology used describes this motion according to its direction relati ...

and

supination Motion, the process of movement, is described using specific anatomical terms. Motion includes movement of organs, joints, limbs, and specific sections of the body. The terminology used describes this motion according to its direction relati ...

when performed against resistance * Pain during axial pressure

X-rays

Osteoarthritis between the

radius bone The radius or radial bone is one of the two large bones of the forearm, the other being the ulna. It extends from the lateral side of the elbow to the thumb side of the wrist and runs parallel to the ulna. The ulna is usually slightly longer tha ...

and the carpals is indicated by a ''radiocarpal joint space'' of less than 2mm. SLAC Because SLAC results from scapholunate ligament rupture, there is a larger space between the two bones, also known as the

Terry Thomas sign In radiology, the Terry-Thomas sign is a scapholunate ligament dissociation on an anteroposterior view of the wrist. Most commonly a result of a fall on the outstretched hand ( FOOSH), the scapholunate ligament ruptures resulting in separation of t ...

. Osteoarthritis and a space larger than 3 mm is suspicious and a space larger than 5 mm is a proven SLAC pathology. Scaphoid instability due to the ligament rupture can be stactic or dynamic. When the X-ray is diagnostic and there is a convincing Terry Thomas sign it is a static scaphoid instability. When the scaphoid is made unstable by either the patient or by manipulation by the examining physician it is a dynamic instability. SNAC In order to diagnose a SNAC wrist you need a PA view X-ray and a lateral view X-ray. As in SLAC, the lateral view X-ray is performed to see if there is a DISI. Computed tomography (CT) or

Magnetic Resonance Imaging Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio wave ...

(MRI) are rarely used to diagnose SNAC or SLAC wrist osteoarthritis because there is no additional value. Also, these techniques are much more expensive than a standard X-ray. CT or MRI may be used if there is a strong suspicion for another underlying pathology or disease.

Treatment

Post-traumatic wrist osteoarthritis can be treated conservatively or with a surgical intervention. In many patients, a conservative (non-surgical) approach is sufficient. Because osteoarthritis is progressive and symptoms may get worse, surgical treatment is advised in any stage.

Stage I

For stage I, normally, nonsurgical treatment is sufficient. This type of therapy includes the use of splint or cast immobilization, injections of corticosteroid in the pain causing joints and the use of a systemic

non-steroidal anti-inflammatory drug Non-steroidal anti-inflammatory drugs (NSAID) are members of a therapeutic drug class which reduces pain, decreases inflammation, decreases fever, and prevents blood clots. Side effects depend on the specific drug, its dose and duration of ...

to reduce pain and improve the functional use of the affected joint. However, the amount of pain that can be suppressed by nonsurgical therapy is limited and with the progression of the wrist osteoarthritis surgical treatment is inevitable. In stage I surgical treatment often consists of

neurectomy A neurectomy is a type of nerve block involving the severing or removal of a nerve. This surgery is performed in rare cases of severe chronic pain where no other treatments have been successful, and for other conditions such as vertigo, involuntary ...

of the

posterior interosseous nerve The posterior interosseous nerve (or dorsal interosseous nerve) is a nerve in the forearm. It is the continuation of the deep branch of the radial nerve, after this has crossed the supinator muscle. It is considerably diminished in size compared t ...

and is often combined with other procedures. In the case of a SLAC, the scapholunate ligament can be reconstructed in combination with a radial styloidectomy, in which the radial styloid is surgically removed from the distal radius. In the case of a SNAC, the scaphoid can be reconstructed by fixating the scaphoid with a screw or by placing a

bone graft Bone grafting is a surgical procedure that replaces missing bone in order to repair bone fractures that are extremely complex, pose a significant health risk to the patient, or fail to heal properly. Some small or acute fractures can be cured wit ...

(Matti-Russe procedure) to increase the stability of the scaphoid. Four corner fusion-2

Stage II

In the treatment of stage II wrist osteoarthritis, there are two treatment options that have proved to be most successful. The first treatment option is proximal row carpectomy. During this surgical intervention the proximal row of the carpal bones is removed (scaphoid, lunate, triquetrum, pisiform). It is important that the radioscaphocapitate ligament is left intact, because if the ligament is not preserved the capitate bone will translate to the ulnar side of the wrist and move away from the distal radius. The new formed joint between the capitate and the lunate fossa of the distal radius is not as congruent as the former scaphoid-lunate-radius joint, however the results of proximal row carpectomy are generally excellent. In patients older than 40 years proximal row carpectomy is preferred because these patients have a small chance of developing osteoarthritis in the new formed capitate-radial joint during their remaining life. Patients younger than 40 years have a big chance to develop osteoarthritis in the radiocapitate joint. These patients have longer to live, therefore the incongruence of the joint will exist for a longer time. Thus, in this patient population four-corner arthrodesis is the treatment of first choice. The capitate, lunate, hamate and triquetrum are bounded together in this procedure and the scaphoid is excised. Before the arthrodesis is executed, the lunate must be reduced out of DISI position. Because the radiolunate joint is typically preserved in stage II SLAC and SNAC wrists, this joint can be the only remaining joint of the proximal wrist. Both procedures are often combined with wrist denervation, as described in the text of treatment stage I.

Stage III

The only treatment option for stage III wrist osteoarthritis is four-corner arthrodesis, as described above in stage II. Proximal row carpectomy is not an option, because in stage III patients the capitate is already affected by the osteoarthritis. So, this procedure would merely lead to a new painful joint.

Stage IV

In this stage there are two surgical treatment options; total wrist

arthroplasty Arthroplasty (literally " e-orming of joint") is an orthopedic surgical procedure where the articular surface of a musculoskeletal joint is replaced, remodeled, or realigned by osteotomy or some other procedure. It is an elective procedure that i ...

and total wrist

arthrodesis Arthrodesis, also known as artificial ankylosis or syndesis, is the artificial induction of joint ossification between two bones by surgery. This is done to relieve intractable pain in a joint which cannot be managed by pain medication, spli ...

. Total wrist arthrodesis has become the standard surgical treatment for patients with stage IV wrist osteoarthritis. During this procedure the carpal bones are all fused together and are then fastened to the distal radius. Patients who still want to undertake heavy labor benefit the most of this surgical approach, because after surgery and recovery this is still possible. However, the arc of motion is extremely diminished by this type of surgery. The best option for those who wish for a motion-sparing procedure is total wrist arthroplasty. However, impact loading should be avoided, an object heavier than 4.5 kg should not be lifted. So, this surgical approach has postoperative activity restrictions. Nevertheless, patients with a total wrist arthrodesis on one side and a total wrist arthroplasty on the other, prefer the total wrist arthroplasty. The procedure exists of a couple of elements. First, the proximal row is removed and the distal row is fastened to the metacarpals. Then, one side of the arthroplasty is placed upon the distal row and the other side on the distal radius. Additionally, the head of the ulna is removed.

References

{{Commons category, Wrist osteoarthritis Arthritis Skeletal disorders