• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
  • Home
  • About
  • Newsletter/Updates
  • Contact Us
  • Policies

Bone and Spine

Orthopedic health, conditions and treatment

  • General Ortho
  • Procedures
  • Spine
  • Upper Limb
  • Lower Limb
  • Pain
  • Trauma
  • Tumors

Ulnar Variance – Normal Values, Measurement and Abnormalities

By Dr Arun Pal Singh

In this article
    • Normal Ulnar Variance
      • Negative Ulnar Variance
      • Positive Ulnar Variance
    • How is Ulnar Variance Measured?
      • Related

Last Updated on November 3, 2020

Ulnar variance [also called Hulten variance] refers to the difference between the levels of distal radial and ulnar articular surfaces. As we know wrist is formed by the articulation of the distal radius, distal ulna, and carpal bones.

Normally, the radial articular surface lies slightly in a distal position than the ulnar articular surface.

Many anatomical variations and conditions may lead to a change in the normal relative arrangement of radius and ulna.

Ulnar variance, therefore, is the measurement of the length of the ulna compared to the radius.

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 <1mm.

It is positive if the ulnar articular surface is distal to radial.

Positive variance can lead to wrist pain because of increased impaction and stress on the lunate and triquetrum.

It is negative if the ulnar articular surface is proximal to radial.

The variance is lower in males than in females. It is less in younger age and tends to increase as we grow older.

The variance is affected by relative positions of radius and ulna. Therefore, it is different in different anatomical positions

It becomes more positive in pronation and gripping whereas negative ulnar variance is seen in supination.

Normal Ulnar Variance

There are a lot of studies that have measured the true values of ulnar variance and its normal variations. The most cited value of is 0.9 mm (range: -4.2 to +2.3 mm).

The different variance values also signify the distribution of load borne by individual bones i.e. radius and ulna on the wrist.

In case of neutral variance, 80% of load is borne by radius and 20% load is borne by ulna.

A 2.5 mm increase in is said to increase the load on the ulnocarpal joint to about 40% and a decrease of 2.5 mm decrease the load to about 4%.

The following table shows the variation of the load with a change in variance

Ulnar Variance Length Difference Load Passing Through Radius Load Passing Through Ulna
Positive

Positive

+2mm 60% 40%
+1mm 70% 30%
Neutral 0 (<1mm) 80% 20%
Negative -1mm 90% 10%
-2mm 95% 5%

Negative Ulnar Variance

  • Kienbock’s disease [Osteonecrosis of lunate bone]
  • Reverse Madelung disease

Positive Ulnar Variance

There could be many causes of the positive value of the variance. Common causes are given as follows

  • Scapholunate instability
  • Ulnar impaction syndrome
  • Triangular Fibrocartilage tears
  • Lunotriquetral ligament tears [Ligaments between lunate bone and triquetral bone]
  • Previous excision of the radial head
  • Increased age
  • Child gymnasts [stress related changes in the distal radial physis]
  • Madelung deformity

How is Ulnar Variance Measured?

It is measured on posteroanterior radiographs with the wrist in neutral rotation.

For x-ray measurement, the following position is recommended

  • The shoulder is abducted to 90 degrees
  • The elbow is flexed to 90 degrees
  • The forearm is in a neutral position and the hand aligned with the forearm axis

A transverse line is drawn perpendicular to the axis of the radius bone, at the level of the lunate fossa (touching the ulnar half of the articular surface of the radius).

A second transverse line is drawn at the level of the ulnar head.

The lunate fossa is the articular depression on the distal radius articular surface that articulates with lunate carpal bone.

Measurment of Ulnar Variance
Measurement of Ulnar Variance

The distance between the two lines indicates ulnar variance.

The value of the variance changes with wrist position (more positive with maximum forearm pronation and negative with maximum forearm supination) and increases significantly during a firm grip.

Therefore, to determine ulnar variance on radiographs the wrist should be in neutral forearm rotation, the elbow flexed 90° and the shoulder abducted 90°.

It is worthy of mention that the length of ulnar styloid does not affect the value of the variance.

Image Credit : http://emedicine.medscape.com/article/398406-overview

Related

Spread the Knowledge
26
Shares
 
26
Shares
125   

Filed Under: Anatomy

About Dr Arun Pal Singh

Arun Pal Singh is an orthopedic and trauma surgeon, founder and chief editor of this website. He works in Kanwar Bone and Spine Clinic, Dasuya, Hoshiarpur, Punjab.

This website is an effort to educate and support people and medical personnel on orthopedic issues and musculoskeletal health.

You can follow him on Facebook, Linkedin and Twitter

Primary Sidebar

Browse Articles

lateral view of fracture of of shaft of femur

Shaft Femur Fracture

Shaft femur fracture is the fracture of the diaphysis of the femur, an area from the subtrochanteric region to supracondylar region. The management of these fractures differ greatly from fractures of the other regions and hence are The femoral shaft Fracture of shaft of the femur or simply called as femur fracture may be categorized […]

MRI showing Cervical Spondylotic Myelopathy

Cervical Spondylotic Myelopathy Symptoms & Treatment

Cervical spondylotic myelopathy refers to cervical spinal cord compression secondary to degenera­tive changes within the cervical spine. Degenerative changes in the cervical spine are called cervical spondylosis. In advanced stages, cervical spondylosis can cause compression of the spinal cord and produce symptoms like which often develop insidiously and are characterized by neck stiffness, arm pain, […]

bilateral wrist xrays

Arthritis – Definition, Types, Symptoms and Treatment

Arthritis [Plural – arthritides]  means inflammation in joint. The term includes all the causes of joint inflammation which are about hundred in number. Pain is the most frequent complaint, the pattern of which may differ with arthritis type. Thought arthritis has many causes, the common outcome is the deterioration of joint surfaces and progressive loss of […]

Trigger point diagram

Trigger Point Causes, Types and Treatment

Also called a myofascial trigger point, the trigger point is a hyperirritable spot in skeletal muscle. These are associated with palpable nodules in taut bands of muscle fibers. It is believed that palpable nodules are tiny contraction knots and a common cause of pain. Myofascial pain syndrome is a common painful muscle disorder characterized by […]

snapping hip syndrome

Snapping Hip Syndrome

In snapping hip syndrome there is an audible snap or click that occurs in or around the hip. Snapping hip syndrome may be called External – Snapping of the iliotibial band or gluteus maximus over the greater trochanter Internal – Snapping of the iliopsoas tendon The condition occurs most often in individuals aged 15-40 years […]

heel spur xray

Heel Spur – Causes, Symptoms and Treatment

A heel spur is a small bony outgrowth or osteophyte on the underside of the heel. The heel spur is generally seen in middle-aged persons but can be found in other age groups too. The heel spur is commonly believed to be a cause of heel pain which is not true as heel spur is […]

anatomical planes of body

Anatomical Position, Planes and Locations

Anatomical Position of Human Body Anatomical position is the basic premise or central tenet, the very core on which all the details of anatomy are based. Thus, to understand the anatomy of the human body, the anatomical position has always to be remembered. The anatomical position of the human body is The person standing erect […]

© Copyright: BoneAndSpine.com
Manage Cookie Consent
The site uses cookies. Please accept cookies for a better visiting experience.
Functional Always active
The technical storage or access is strictly necessary for the legitimate purpose of enabling the use of a specific service explicitly requested by the subscriber or user, or for the sole purpose of carrying out the transmission of a communication over an electronic communications network.
Preferences
The technical storage or access is necessary for the legitimate purpose of storing preferences that are not requested by the subscriber or user.
Statistics
The technical storage or access that is used exclusively for statistical purposes. The technical storage or access that is used exclusively for anonymous statistical purposes. Without a subpoena, voluntary compliance on the part of your Internet Service Provider, or additional records from a third party, information stored or retrieved for this purpose alone cannot usually be used to identify you.
Marketing
The technical storage or access is required to create user profiles to send advertising, or to track the user on a website or across several websites for similar marketing purposes.
Manage options Manage services Manage {vendor_count} vendors Read more about these purposes
View preferences
{title} {title} {title}
 

Loading Comments...