EP001 - Knife Wound to Thumb Assessment

This episode draws upon clinical scenarios from the official AMC Handbook of Clinical Assessment, published by the Australian Medical Council. All cases presented herein are intended solely for educational and discussion purposes. We offer personal insights and clinical interpretations to facilitate AMC candidates in enhancing their clinical reasoning skills. The AMC Handbook is the intellectual property of the Australian Medical Council. For access to the official material, please visit the AMC website.

In this episode, we analyse a clinical case involving a 22-year-old male who presented to the Emergency Department with a laceration on his left thumb. The patient, employed as an orchard labourer and fruit picker, sustained the injury while pruning fruit trees with a knife. Although the initial bleeding was minimal and managed effectively, the laceration was characterised as a linear knife wound located near the thumb.

This case centres on the assessment and management of potentially significant injuries associated with skin wounds, with particular emphasis on the risk of severed tendons. A crucial finding in this case is the patient’s inability to actively extend the joints of the thumb, suggesting possible damage to the thumb's extensor tendons. The tendons most likely affected are the Extensor Pollicis Longus (EPL) and the Extensor Pollicis Brevis (EPB), which are responsible for extending the interphalangeal (IP) and metacarpophalangeal (MP) joints of the thumb, respectively.

We will examine the essential steps involved in managing such an injury, including the thorough examination and assessment of the wound, the appropriate communication of the injury's nature and recommended management to the patient, and the critical importance of identifying deeper tendon injuries. Our discussion will also address important considerations such as anesthesia options (regional block versus general anesthesia) for surgical intervention, tetanus prophylaxis, and the potential need for antibiotics. The primary surgical repair is recommended for this type of "tidy" wound. It is vital to recognise and assess for injuries to the extensor tendons, as failing to do so represents a significant oversight in this scenario.