STUDY DESIGN: A case report. OBJECTIVE: To present a previously unreported cause of neurologic compromise after cervical spine surgery. SUMMARY OF BACKGROUND DATA: Several different causes of postoperative neurologic deficit have been reported in the literature. The authors present a case of acute postoperative paralysis after posterior cervical decompression by a mechanism that has not yet been reported in the literature. METHODS: A 54-year-old muscular, short-statured man underwent posterior cervical laminectomy from C3-C5 without instrumentation and left C5 foraminotomy. Within hours of leaving the operating room, he began to develop postoperative neurologic deficits in his extremities, which progressed to a classic Brown-Sequard syndrome. Magnetic resonance imaging revealed regional kyphosis and large swollen paraspinal muscles impinging on the spinal cord without epidural hematoma. Emergent operative re-exploration confirmed these findings; large, swollen paraspinal muscles, a functioning drain, and no hematoma were found. RESULTS: The patient was treated with immediate corticosteroids at the time of initial diagnosis, and emergent re-exploration and debulking of the paraspinal muscles. The patient had complete recovery of neurologic function to his preoperative baseline after the second procedure but required a third procedure in which anterior discectomy and fusion at C4-C5 was performed, which led to improvement of his preoperative symptoms. CONCLUSION: When performing posterior cervical decompression, surgeons must be aware of the potential for loss of normal lordosis and anterior displacement of paraspinal muscles against the spinal cord, especially in muscular patients.