An Unusual Case of Unilateral Foot Drop and Deep Vein Thrombosis Following Electroconvulsive Therapy in a Middle-Aged Patient With Depression

Electroconvulsive therapy (ECT) is a well-known, generally safe, and effective treatment modality for severe mental health disorders, including catatonic depression, after other forms of approved treatments have failed. Like most procedures, ECT is known to have some adverse effects, such as transient headaches and transient amnesia; however, neurological complications would be classed as exceptionally rare, especially with the modified ECT. We report the case of a 54-year-old woman with a recurrent depressive disorder with catatonic features who presented with low mood, reduced energy levels, loss of appetite with refusal of oral intake, intense suicidal ideation and attempts, mutism, psychomotor retardation, and eventual lack of movement. She was initially stabilized on the medical ward and commenced ECT. After the fourth session, there was an appreciable improvement in her mood and activity levels, and then she complained of weakness in her right foot, which was later confirmed clinically to be a right-sided foot drop. Despite having had two previous sessions of ECT in past years, this was the first time she was experiencing such a symptom following the procedure. ECT was discontinued, and she is being managed conservatively with leg splints by the trauma and orthopedics team and physiotherapists. A few days following the sudden foot drop, she complained of swelling in her right ankle and pain in her right calf. Upon examination and investigation, a deep venous thrombosis (DVT) was discovered in the right leg. This is the second time she has had DVT following a catatonic depressive disorder, and she is being managed by the anticoagulation team. This case highlights an extremely rare but possible complication of ECT, which is foot drop, as there are similar cases highlighted in other literature. Although a direct link between ECT and foot drop and/or DVT has not been established, it is important to explore possible reasons why patients may be at risk of these two conditions.