The etonogestrel implant has been available in Australia since 2001. General practitioners routinely insert and remove these implants in their rooms under local anaesthetic. We report two cases of significant median nerve injury following inappropriate dissection of the arm to remove this device when impalpable. These cases illustrate the need to follow the product guidelines and to refer impalpable or deeply placed implants for imaging and subsequent removal under ultrasound guidance or by a qualified surgeon.
Case study 1
A woman, 44 years of age, presented to a hand clinic in 2010 with a partial high median nerve lesion, 7 days after attempted removal of an impalpable etonogestrel implant. During the initial removal procedure she experienced a sudden shooting pain down her arm, followed by paraesthesia and dysaesthesia in her hand. The procedure was discontinued, and she attended a hospital emergency department.
Ultrasound showed the implant to be separate from the incision and in the subcutaneous plane. Its location was marked and she was referred to a hand clinic. At that stage, she had weakness of the muscles innervated by the median nerve and significant dysaesthesia and paraesthesia throughout its sensory distribution. The wound was explored under general anaesthesia 7 days from the original procedure, and a 10% laceration of the median nerve was repaired under the operating microscope. The implant was removed through a separate incision. Four months after the injury she had persistent weakness of her thenar muscles, however, her major disability was persistent dysaethesia and paraesthesia in her hand, which required treatment by a pain specialist.
Download the PDF for the full article.