Cubitus varus is a common deformity in which the extended forearm is deviated towards midline of the body .

Cubitus varus is often referred to as 'Gunstock deformity', due to the crooked nature of the healing.

The "opposite" condition is cubitus valgus

Cubitus valgus

Cubitus valgus is a medical deformity in which the elbows are turned in. A small degree of cubitus valgus is acceptable and occurs in the general population....

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Causes

A common cause is the supracondylar fracture of humerus. It can be corrected via a corrective osteotomy

Osteotomy

An osteotomy is a surgical operation whereby a bone is cut to shorten, lengthen, or change its alignment. It is sometimes performed to correct a hallux valgus, or to straighten a bone that has healed crookedly following a fracture. It is also used to correct a coxa vara, genu valgum, and genu varum...

 of the humerus and either internal or external fixation of the bone until union.

Diagnosis

Cubitus varus is not able to be diagnosed until after healing of the prior fracture, as the arm must be in full extension, not flexion, for the deformity to be noticed.

Prognosis

A cubitus varus deformity is more cosmetic than limiting of any function, however internal rotation

Internal rotation

In anatomy, internal rotation is rotation towards the center of the body.The muscles of internal rotation include:* of arm/humerus at shoulder** Deltoid muscle** Subscapularis** Teres major** Latissimus dorsi...

 of the radius

Radius

In classical geometry, a radius of a circle or sphere is any line segment from its center to its perimeter. By extension, the radius of a circle or sphere is the length of any such segment, which is half the diameter. If the object does not have an obvious center, the term may refer to its...

 over the ulna

Ulna

The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form and runs parallel to the radius, which is shorter and smaller. In anatomical position The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form...

 may be limited due to the overgrowth of the humerus. This may be noticeable during an activity such as using a computer mouse.

Complications

Instances in which the medial epicondyle

Medial epicondyle

Medial epicondyle can refer to:* Medial epicondyle of the humerus * Medial epicondyle of the femur...

 of the distal humerus is malformed due to the initial fracture at the humeral endplate may result in subluxation

Subluxation

A subluxation may have different meanings, depending on the medical specialty involved. It implies the presence of an incomplete or partial dislocation of a joint or organ. The World Health Organization defines both the medical subluxation and the chiropractic subluxation...

 (snapping) of the ulnar nerve

Ulnar nerve

In human anatomy, the ulnar nerve is a nerve which runs near the ulna bone. The ulnar collateral ligament of elbow joint is in relation with the ulnar nerve. The nerve is the largest unprotected nerve in the human body , so injury is common...

 over the medial epicondyle with active flexion and extension of the elbow. In such instances, conductance of the ulnar nerve

Ulnar nerve

In human anatomy, the ulnar nerve is a nerve which runs near the ulna bone. The ulnar collateral ligament of elbow joint is in relation with the ulnar nerve. The nerve is the largest unprotected nerve in the human body , so injury is common...

 may be compromised due to chronic irritation, potentially resulting in irreversible ulnar neuropathy

Ulnar neuropathy

Ulnar neuropathy is a disorder involving the ulnar nerve. Ulnar neuropathy may be caused by entrapment of the ulnar nerve at the elbow or wrist with resultant numbness and tingling into the fourth and fifth fingers....

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