Cubital Valgus is the condition in which the forearm has laterally deviated from normal anatomical deviation in full extension. A certain lateral deviation is acceptable in an elbow. Pathologically some of the causes are explained below;
Causes
- Nonunited fracture lateral condyle
- Malunited supracondylar fracture of humerus
- Osteonecrosis of lateral trochlea
- Malunited intercondylar fractures
- Radial head fracture-dislocation
- Medial epiphysis injury and growth stimulation
Non-Union of lateral condyle is called after 12 weeks / 3 months of fracture.
Components of lateral condyle
- Lateral trochlear crista
- Lateral condylar physis and epicondyle
- Capitellum and lateral metaphyseal region
Lateral condylar fracture: Epiphyseal intraarticular fracture
Why non union is so common in lateral condyle fracture?
- Poor circulation to metaphyseal fragment
- Fragment bathed by synovial fluid
- Forces exerted by muscles arising from condylar fragment keeping it displaced
- Displaced fragment with the opposition of articular cartilage to the proximal fracture surface; In this scenario union is impossible
Classifications
Jakob’s Classification
| Stages | Features |
|---|---|
| Stage I | Undisplaced with the intact articular surface (Badelon modified displacement < 2 mm) |
| Stage II | Complete fracture through the articular surface |
| Stage III | Fragment rotated, displaced laterally and proximally allowing translocation of olecranon and radial head |
Fracture line runs between ECRB and Brachioradialis
Causes of cubitus valgus
Type I:
Fracture with healing there may be the development of bony bar or arrest of lateral growth due to injury to the ossification center
Type II:
Can’t be held securely in place with conservative methods being inherently unstable, so there is always a tendency toward lateral and proximal migration
In a united fracture, there could be the formation of the bony bar which tethers lateral growth
Cubitus valgus due to nonunion lateral condyle / united fractures is Progressive. It changes elbow mechanics and develops neurological complications, examples: Tardy Ulnar Nerve Palsy
Tardy Ulnar Nerve Palsy
Due to
- Stretching of the nerve due to medial angulation and hence resulting lengthier course
- Friction induced perineuritis
- Adhesion causing entrapment of the nerve in the cubital tunnel
Management
Surgical Management
Absolute Indications :
- Progressive deformity
- Associated tardy nerve palsy
- Elbow instability
Symptomatic patient based on Flynn criteria
- Large metaphyseal fragment
- Displacement > 1 cm from joint space
- Open viable lateral condylar physis
Options:
Asymptomatic nonprogressive nonunion in an adult patient with tardy ulnar nerve palsy: Transposition of ulnar nerve
If articular cartilages oppose fracture surfaces-> Debridement of the fracture surface + Rigid fixation + Bone grafting + transposition of ulnar nerve
Patient with:
See also : Cubitus Varus
See also: The Stiff Elbow
See also: The Unstable Elbow
