Stun gun induced myotendinous injury of the iliopsoas and gluteus minimus

We report a 57-year-old man with a complete tear of his iliopsoas tendon at the distal myotendinous junction, a near complete tear of the iliopsoas tendon at the lesser trochanter of the femur, and a high-grade tear of his gluteus minimus tendon at the greater trochanter of the femur after being struck by a stun gun in the proximal left thigh. The stun gun discharge resulted in a forced contraction of the left hip flexor muscles, which resulted in pain, weakness and difficulty with active hip flexion. Three months after the being struck with the stun gun, the patient underwent magnetic resonance imaging (MRI) of the left hip. MRI of the left hip revealed a complete tear of the left iliopsoas tendon from the lesser trochanter with 4 cm of proximal retraction and a high-grade strain of the gluteus minimus tendon at the greater trochanter. The distal iliopsoas myotendinous junction and lesser trochanter tendon insertion were surgically repaired. This case illustrates that a stun gun can cause acute rupture of the iliopsoas tendon and tear of the gluteus minimus tendon, which is well visualized on MRI.