Environmental injuries include sunburn, frostbite, or contact dermatitis.Less common causes of external ear pain include:
Auricular Cellulitis: a superficial infection of the ear that may be precipitated by trauma, an insect bite, or ear piercing
Perichondritis: infection of the perichondrium, or fascia surrounding the ear cartilage, which can develop as a complication of untreated auricular cellulitis. It is important to identify and treat perichondritis with antibiotics to avoid permanent ear deformities. Relapsing polychondritis: a systemic inflammatory condition involving cartilage in many parts of the body, but often including the cartilage of both ears. The severity and prognosis of the disease varies widely. Otitis externa
Otitis externa, also known as "swimmers ear", is a cellulitis of the external ear canal. In North America, 98% of cases are caused by bacteria, and the most common causative organisms are Pseudomonas and Staph aureus. Risk factors include exposure to excessive moisture (e.g. from swimming or a warm climate) and disruption of the protective cerumen barrier, which can result from aggressive ear cleaning or placing objects in the ear.Malignant otitis externa is a rare and potentially life-threatening complication of otitis externa in which the infection spreads from the ear canal into the surrounding skull base, hence becoming an osteomyelitis. It occurs largely in diabetic patients. It is very rare in children, though can be seen in immunocompromised children and adults. Pseudomonas is the most common causative organism. The pain tends to be more severe than in uncomplicated otitis externa, and laboratory studies often reveal elevated inflammatory markers (ESR and/or CRP).
The diagnosis is made by the combination of symptoms and examination of the tympanic membrane for redness, bulging, and/or a middle ear effusion (collection of fluid within the middle ear).Complications of otitis media include hearing loss, facial nerve paralysis, or extension of infection to surrounding anatomic structures, including:
Mastoiditis: infection of the air cells in the mastoid process, the area of the skull located right behind the ear
Petrositis: infection of the petrous portion of the temporal bone
Labyrinthitis
Meningitis
Subdural abscess
Brain abscess
Cerebral venous sinus thrombosis

Trauma
Barotrauma: results from changes in atmospheric pressure that occur when descending in a plane or deep diving. As atmospheric pressure increases with descent, the eustachian tube collapses due to pressure within the middle ear being less than the external pressure, which causes pain. In severe cases, middle ear hemorrhage or tympanic membrane rupture can result. Tympanic membrane rupture: disruption of the eardrum. This can be caused by a blow to the ear, blast injury, barotrauma, or direct penetration of the tympanic membrane by an object entering the ear. Referred ear pain
A variety of conditions can cause irritation of one of the nerves that provides sensation to the ear. Conditions causing irritation the trigeminal nerve (cranial nerve V):
Temporomandibular joint syndrome: inflammation or abnormal movements of the joint between the jaw and skull. These disorders are most common in women of childbearing age, and are uncommon in children younger than 10 years old. Myofascial pain syndrome: pain in the muscles involved in chewing.