Describe orbital fractures and the other orbital injuries.

Orbital Fractures

• The orbit is a pyramid of seven bones with walls of very different strength, and the pattern of fracture follows directly from that: the floor (maxilla, thinnest over the infraorbital groove) and the medial wall (lamina papyracea of the ethmoid, paper-thin) are the weakest and fracture most often, while the lateral wall and roof are strong
• The blow-out fracture is the classical injury: a blunt object larger than the orbital rim — a fist, a ball, an elbow — strikes the globe and periorbital tissue, raises the intraorbital pressure abruptly, and the floor gives way, decompressing the orbit into the maxillary sinus while the rim remains intact. It is in one sense protective, sparing the globe
• Clinical features — periorbital swelling and bruising; surgical emphysema with crepitus, worse on nose-blowing, which indicates communication with a sinus and about which the patient must be warned; diplopia, characteristically on upgaze and downgaze, from tethering or entrapment of the inferior rectus and surrounding tissue; enophthalmos, which is often masked initially by swelling and declares itself as the oedema settles; infraorbital hypoaesthesia of the cheek, lower lid, side of the nose, upper lip and upper teeth, from injury to the infraorbital nerve; and a positive forced duction test, which distinguishes mechanical entrapment from a nerve palsy or simple oedema

Other Orbital and Adnexal Trauma

• Do not be distracted by the eye in a multiply injured patient: airway, breathing, circulation and the cervical spine come first, and the head injury may be the reason for the visual loss
• Assess and document vision and pupils early in any facial trauma, before the lids swell shut and while the patient can still cooperate — because once they are closed, assessment becomes very difficult and the pupils are the only remaining sign
• The floor and medial wall are the weak walls, and fracture far more often than the strong roof and lateral wall
• A blow-out fracture decompresses the orbit and in that sense protects the globe.
• Enophthalmos is masked by early swelling and declares itself as the oedema settles, so reassessment at a week is essential
• Infraorbital hypoaesthesia is highly suggestive, and covers the cheek, lower lid, nose, upper lip and upper teeth
• Forced duction separates entrapment from palsy, and is the single most useful test in a restricted eye after facial trauma
• Warn against nose-blowing; it forces air into the orbit and can produce dramatic surgical emphysema or compress the optic nerve
• A medial wall fracture mimics a sixth nerve palsy, limiting abduction through medial rectus entrapment