Presented By: Nicole Occidental, University of Arkansas for Medical Sciences
Co-Authors: Tiffany Huitt, University of Arkansas for Medical Sciences
Erica Malone, University of Arkansas for Medical Sciences
Weston Northington, University of Arkansas for Medical Sciences
Anders Nowell, University of Arkansas for Medical Sciences
Kimberly O'Brien, University of Arkansas for Medical Sciences
Sara Ottinger, University of Arkansas for Medical Sciences

Purpose
During cadaver dissections, medical students encounter unexpected findings and variations. Occasionally, findings prompt further research and reflection towards clinical significance. This study's purpose is to describe how abnormal findings prompted further investigations into causes and related processes impacting long-term quality of life.

Methods 
This report is initiated by the observations of five first-year medical students who performed a dissection of a female donor in her late 90's. During dissection, they discovered an absence of the right psoas major and iliacus muscles. Evidence of a midline abdominal scar, and staples along the right iliac fossa and along the right side of her vertebral column, indicated surgical removal.

Results 
The rare absence of these muscles prompted students to investigate the underlying causes and impact on quality of life. Related literature indicates the most likely explanation for the absence of these muscles is an iliopsoas resection associated with surgical removal of a retroperitoneal sarcoma. Other surgical options for the removal of these muscles are unlikely given the role these muscles play in hip flexion and ambulation. Further investigation revealed issues related to the absent muscles. The most notable of these was scoliosis exacerbated by unbalanced hip flexors. Severe scoliosis is a risk factor for hiatal hernias, and is associated with decreased lung capacity, which were evident in this donor. Finally, the lack of mobility in her right leg contributed to the fat infiltration in her anterior thigh muscles.

Conclusion
Cadaver dissection often leads to discoveries of unique pathologies and anatomical findings. In this case, the absence of the iliopsoas muscle intrigued students and faculty, sparking further investigations and learning. This investigation provided insight into the quality of life the donor may have experienced and provided students a more complete picture of how she lived and died.