Cubitus varus is a
varus 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.
Signs and symptoms
Complications
Instances in which the
medial epicondyle of the distal humerus is malformed due to the initial fracture at the humeral endplate may result in
subluxation (snapping) of the
ulnar nerve
In human anatomy, the ulnar nerve is a nerve that runs near the ulna bone. The ulnar collateral ligament of elbow joint is in relation with the ulnar nerve. The nerve is the largest in the human body unprotected by muscle or bone, so injury is ...
over the medial epicondyle with active flexion and extension of the elbow. In such instances, conductance of the ulnar nerve may be compromised due to chronic irritation, potentially resulting in irreversible
ulnar neuropathy
Ulnar neuropathy is a disorder involving the ulnar nerve. Ulnar neuropathy may be caused by entrapment of the ulnar nerve with resultant numbness and tingling. It may also cause weakness or and paralysis of the muscles supplied by the nerve.
Si ...
.
Causes
A common cause is a
supracondylar fracture
A supracondylar humerus fracture is a fracture of the distal humerus just above the elbow joint. The fracture is usually transverse or oblique and above the medial and lateral condyles and epicondyles. This fracture pattern is relatively rare in a ...
of the humerus. It can be corrected via a corrective
osteotomy of the humerus and either internal or external fixation of the bone until union.
[ Rüdiger Döhler: ''Suprakondyläre Korrekturosteotomie beim posttraumatischen Cubitus varus''.
Unfallchirurg 105 (2002), p. 397-400]
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 of the
radius over the
ulna may be limited due to the overgrowth of the humerus. This may be noticeable during an activity such as using a
computer mouse.
References
External links
{{Congenital malformations and deformations of musculoskeletal system
Congenital disorders of musculoskeletal system
Arthropathies