Dynamic cord compression induced by proximal junctional failure and loose pedicle screws after thoracolumbar fusion surgery: a case report

BMC Musculoskeletal Disorders, 2023 · DOI: https://doi.org/10.1186/s12891-023-06791-2 · Published: January 1, 2023

Simple Explanation

This case report describes a situation where a patient experienced numbness in their leg after spinal fusion surgery. The usual imaging tests didn't show any compression of the spinal cord, which made it difficult to figure out what was wrong right away. The problem was that the screws used in the surgery were moving around and causing the spinal cord to be compressed at certain times, but not all the time. Standard imaging, which is done while lying down, didn't catch this dynamic compression. The doctors realized that they needed to consider that the spinal cord compression could be happening only when the patient was standing or moving. They suggest that doctors should use both lying down and standing up X-rays to diagnose this kind of problem.

Study Duration

1 year

Participants

A 71-year-old female

Evidence Level

Level 4, Case Report

Key Findings

1
Lower extremity numbness can be the first symptom of proximal junctional failure (PJF) with myelopathy following spinal fusion surgery.
2
Standard static imaging, such as MRI and CT scans performed in a supine position, may not always reveal spinal cord compression caused by dynamic instability.
3
Standing radiographs can be an important tool in diagnosing PJF induced by dynamic cord compression.

Research Summary

This case report highlights a rare instance of spinal cord compression due to loosened pedicle screws (PSs) following adult spinal deformity (ASD) surgery, where lower extremity numbness was the initial symptom. The delay in diagnosis was attributed to the lack of visible spinal cord compression on supine MRI and CT scans, emphasizing the importance of recognizing the dynamic nature of proximal junctional failure (PJF). The authors conclude that clinicians should consider spinal cord compression associated with PJF in patients with persistent neurological symptoms after long fusion constructs, and that supine and standing radiographs should be obtained to aid in diagnosis.

Practical Implications

Increased Awareness

Clinicians should be aware that lower extremity numbness can be an initial symptom of PJF after spinal fusion.

Dynamic Imaging

Standing radiographs should be considered in addition to static imaging (MRI, CT) to diagnose dynamic cord compression.

Prompt Diagnosis

Early diagnosis and surgical correction of PJF with myelopathy are crucial to minimize permanent neurological injury.

Study Limitations

1
Single case report limits generalizability.
2
Lack of detailed biomechanical analysis of screw loosening.
3
The study does not explore alternative imaging modalities or diagnostic techniques that may have aided in earlier detection.

Your Feedback

Was this summary helpful?

Back to Surgery