Positive ulnar variance describes where the distal articular surface of the ulna is more than 2.5mm distal to the articular surface of the radius. It plays important role in wrist pathology such as ulnar impaction syndromes and thinning of the triangular fibrocartilage complex.
How is ulnar variance treated?
Ulnar shortening osteotomy (USO) is the standard procedure for correcting positive ulnar variance. Goal of this procedure is to minimize the symptoms by restoring the neutral radio – ulnar variance.
What is ulnar variance in the wrist?
Ulnar Variance is the length of the ulna compared to the length of the radius at the wrist.
Does positive ulnar variance require surgery?
The debridement of the ulna is performed to the degree at which the patient is ulnar neutral or slightly ulnar negative. The benefit of this procedure is that open surgery is not required, and recovery is faster. However, if the ulnar variance is greater than +4mm, this option is not suitable.
What is ulnar variance on xray?
Ulnar variance is a measurement that is taken from X-rays to define the length of the ulna bone relative to the radius. This is an important measurement because the dynamics of the wrist are dependent on the ulna and radius translating force through the wrist. Normally, the translation of forces 80/20.
How do you fix ulnar impaction syndrome?
Conservative treatment should be attempted before surgery and can include immobilization for 6-12 weeks, NSAIDs, corticosteroid injection and limiting aggravating movements such as pronation, gripping and ulnar deviation. Lack of improvement with conservative management is an indication for surgery.
What happens when your ulna bone is too long?
Ulnar impaction syndrome is a condition in which one of the forearm bones (ulna) is too long relative to the other (radius). This results in excessive pressure on the ulnar side of the wrist and causes pain, and wear and tear.
Does negative ulnar variance cause pain?
Signs & Symptoms
These changes may produce pain, swelling, tenderness, thickening and/or stiffness in the overlying tissues of the wrist. The range of motion may become restricted. Many individuals with Kienböck Disease have a shorter ulna than radius (negative ulnar variance).
What causes ulnar impaction?
Ulnar impaction syndrome is a progressive degenerative condition, most commonly resulting from repetitive abutment of a lengthened ulna, with the TFCC, lunate, triquetrum, and lunotriquetral ligament.
How do you assess ulnar variance?
To determine ulnar variance on radiographs, the generally accepted standard view is a posteroanterior view obtained with the wrist in neutral forearm rotation, the elbow flexed 90° and the shoulder abducted 90°.
Is neutral ulnar variance good?
The variance could be neutral, positive and negative. It is said to be neutral if articular surfaces of radius and ulna are at the same level i.e. the difference between ulnar and radial length is
What happens with negative ulnar variance?
Anatomically, negative ulnar variance (UV), may increase the mechanical stress on the lunate exerted by a relatively long radius [3,4]. In addition, individuals with vascular abnormalities including a single blood vessel supply to the lunate are thought to be at a higher risk of developing avascular necrosis [5].
Is ulnar impaction syndrome painful?
When rotating the hand to face up or down, the patient may experience a painful clicking or locking sensation. Although rare as a symptom of UIS, swelling may occur in the wrist or forearm. Range or rotation and motion are also impacted to various degrees when a patient suffers from ulnar impaction syndrome.
Is ulnar shortening worth it?
This procedure has been the standard treatment for ulnar impaction syndrome for many years. Recent biomechanical studies have confirmed that an ulnar shortening osteotomy can improve the stability of the ulnar carpus and distal radioulnar joint (DRUJ).
Is ulnar impaction syndrome serious?
This causes inflammation on the ulnar, or little-finger side, of the hand, and consequently, pain and swelling in the wrist. UIS is a degenerative wrist condition. Oftentimes, degenerative problems are irreversible as well as progressive. Fortunately, ulnar impaction syndrome is curable and treatable.
What causes TFCC tear?
There are two main causes of TFCC tears: Injury: The force of falling on your hand or wrist can tear your TFCC. A fall or other injury that fractures your radius can also tear your TFCC. A sudden twist of your arm that over-rotates your wrist can also cause a TFCC tear.
How is ulnar variance measured in radiology?
To determine ulnar variance on radiographs, the generally accepted standard view is a posteroanterior view obtained with the wrist in neutral forearm rotation, the elbow flexed 90° and the shoulder abducted 90°.
Is negative ulnar variance normal?
Abstract. Negative ulnar variance is a condition in which the ulna is relatively shorter than the radius at the carpus. It was found in 21% of 203 normal wrists.
