Category: Musculoskeletal

231 - Pedicle Screw Displacement Causing Iliopsoas Muscle Injury: A Case Report

wwww, February 15th
17:12 A – 18:12 A

Case Diagnosis: Iliopsoas muscle injury due to a pedicle screw displacement. 

Case Description:
A 48-year-old male with a previous history of L5-S1 spinal fusion and instrumentation placement presented with new onset of pain with right hip flexion and persistent low back pain. Patient described the pain as a constant, 7/10, achy and at times sharp pain, made worse particularly by right hip flexion.  Pain was reproduced with repeated hip flexion resistance motion, which led us to order new imaging. CT scan was performed (images provided) which showed surgical instrumentation failure, notably the right pedicle screw being displaced from the right vertebral body contacting the right iliopsoas muscle. This case stresses the importance of anatomy and physical examination.

Discussions: The iliopsoas is a combination of the psoas major and iliacus muscle. The psoas muscle originates from the vertebral bodies of T12-L3 and the iliacus muscle originates from the iliac fossa of the pelvis. Both muscle groups combine and insert on the lesser trochanter of the femur. The primary motion of the iliopsoas muscle is flexion and lateral rotation of the hip; thus, injury to the iliopsoas muscle would cause pain with hip flexion as represented by our patient.  

The use of pedicle screws for spinal stabilization have become widely used since it serves as a common attachment for all three columns of the vertebrae. However, the anatomical proximity of the iliopsoas muscle to the lumbar pedicles makes the iliopsoas muscle a key target when performing lumbar spinal fusion. As the number of spinal fusions increase, it is imperative to monitor patient’s pain and symptoms following a spinal fusion. Post-laminectomy syndrome is a common cause of pain in patients following back surgery; however, pedicle screw displacement should be considered in patient with new onset of pain or limited function from a musculoskeletal deficit.

Ankur A. Patel

Medical Student
Edward Via College of Osteopathic Medicine
Laurel, Maryland

Neal Shah

Assistant Professor Interventional Pain Management/Anesthesiology
Moffitt Cancer Center
Tampa, Florida

Devang Padalia

Section Chief Interventional Pain
Moffitt Cancer Center
Tampa, Florida

Arpit Patel

Associate Clinical Professor
University of South Florida
Tampa, Florida