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Surgical Approach and Complications of Stand-alone Lateral Trans-Psoas Interbody Fusion
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A multiply split femoral nerve and psoas quartus muscle
T L Wong1, Shogo Kikuta1,2, Joe Iwanaga1,2,3
1Seattle Science Foundation, Seattle, WA, USA.
Anatomy & Cell Biology
|July 25, 2019
Summary
A rare psoas quartus muscle variant was found associated with splits in the femoral nerve. This anatomical anomaly impacts understanding of nerve entrapment and surgical approaches in the lumbar spine.
Area of Science:
- Anatomy
- Surgical Anatomy
- Lumbar Plexus Anatomy
Background:
- The femoral nerve, the largest branch of the lumbar plexus, typically originates from spinal nerves L2-L4.
- It usually lies between the iliacus and psoas major muscles within the pelvis.
- The psoas major muscle originates from vertebrae T12-L5 and inserts onto the lesser trochanter of the femur.
Observation:
- A case involving the presence of a psoas quartus muscle is presented.
- This muscle variant was observed in conjunction with multiple divisions or splits of the femoral nerve.
- The anomaly was noted within the pelvic region.
Findings:
- A previously unreported anatomical variation involving the psoas quartus muscle and aberrant femoral nerve branching was identified.
- The femoral nerve demonstrated unusual splitting patterns associated with this muscle.
- The embryological basis for this variant remains undetermined.
Implications:
- Awareness of this anatomical variant is crucial for clinicians and surgeons.
- Understanding such variations aids in diagnosing and managing pelvic pain and nerve entrapment syndromes.
- Knowledge of this anomaly is important for safely executing surgical procedures in the lumbar region, including lateral transpsoas approaches.
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