Traumatic cataracts occur secondary to blunt or penetrating ocular trauma. Infrared energy (glass-blower's cataract), electric shock, and ionizing radiation are other rare causes of traumatic cataracts. 
Cataracts caused by blunt trauma classically form stellate- or rosette-shaped posterior axial opacities that may be stable or progressive, whereas penetrating trauma with disruption of the lens capsule forms cortical changes that may remain focal if small or may progress rapidly to total cortical opacification.
Note the images below.
See What the Eyes Tell You: 16 Abnormalities of the Lens, a Critical Images slideshow, to help recognize lens abnormalities that are clues to various conditions and diseases.
Lens dislocation and subluxation are commonly found in conjunction with traumatic cataract. Other associated complications include phacolytic, phacomorphic, pupillary block, and angle-recession glaucoma; phacoanaphylactic uveitis; retinal detachment; choroidal rupture; hyphema; retrobulbar hemorrhage; traumatic optic neuropathy; and globe rupture. [2, 3, 4]
Traumatic cataract can present many medical and surgical challenges to the ophthalmologist. Careful examination and a management plan can simplify these difficult cases and provide the best possible outcome. [4, 5]
Blunt trauma is responsible for coup and contrecoup ocular injury. Coup is the mechanism of direct impact. It is responsible for Vossius ring (imprinted iris pigment) sometimes found on the anterior lens capsule following blunt injury. Contrecoup refers to distant injury caused by shockwaves traveling along the line of concussion. 
When the anterior surface of the eye is struck bluntly, there is a rapid anterior-posterior shortening accompanied by equatorial expansion. This equatorial stretching can disrupt the lens capsule, zonules, or both. Combination of coup, contrecoup, and equatorial expansion is responsible for formation of traumatic cataract following blunt ocular injury. [7, 8, 9]
Penetrating trauma that directly compromises the lens capsule leads to cortical opacification at the site of injury. If the rent is sufficiently large, the entire lens rapidly opacifies, but when small, cortical cataract can seal itself off and remain localized.
Approximately 2.5 million eye injuries occur annually in the United States. It is estimated that approximately 4-5% of a comprehensive ophthalmologist's patients are seen secondary to ocular injury. Traumatic cataract may present as acute, subacute, or late sequela of ocular trauma.
Trauma is the leading cause of monocular blindness in people younger than 45 years. Annually, approximately 50,000 people are left unable to read newsprint as a result of ocular trauma. Only 85% patients who experience anterior segment injury reach a final visual acuity of 20/40 or better, whereas only 40% patients with posterior segment injury reach this level. [7, 8]
The male-to-female ratio in cases of ocular trauma is 4:1.
Work- and sports-related eye injuries most commonly occur in children and young adults. Between 1985-1991, a National Eye Trauma System study reported a median age of 28 years in 648 assault-related cases.