Intramuscular hematoma with motor weakness after trigger point injection: A case report.

RATIONALE: Although trigger point injection is known as an easy and low-risk procedure, it is contraindicated to patients with hemorrhagic disorders or who regularly take anticoagulants/antiplatelets. However, taking clopidogrel is not a defined contraindication to this low-risk procedure.

PATIENT CONCERNS: The chief complaint of a 76-year old woman regularly taking clopidogrel was low back and left buttock pain which prolonged for several years.

DIAGNOSES: The patient was diagnosed with L4-5 and L5-S1 spinal stenosis at the orthopedics department and was referred for lumbar spinal epidural steroid injection.

INTERVENTION: She was treated with trigger point injection.

OUTCOMES: Three hours after the injection, she complained motor weakness and pain in the injection area. A hematoma on left gluteus medium muscle was detected with ultrasonography and ultrasound-guided needle aspiration was accomplished to relieve the symptom.

LESSONS: Trigger point injection for patients taking clopidogrel should be done with a caution to prevent such complication.