Differential Diagnosis
- Single most likely diagnosis
- Voluntary retention of stool due to an anal fissure: This is the most likely diagnosis because the patient presents with chronic constipation and new onset of mild thoracic back pain, which could be related to the anatomic short left leg and the resulting S-shaped scoliosis. The constipation could be causing or exacerbating the back pain, and an anal fissure could be the underlying cause of the constipation due to painful defecation leading to voluntary retention of stool.
- Other Likely diagnoses
- Anal sphincter hypertonicity: This could be a contributing factor to the patient's constipation, as increased anal sphincter tone can make it difficult to pass stool.
- Impingement on the superior mesenteric artery: The S-shaped scoliosis could potentially cause impingement on the superior mesenteric artery, leading to chronic abdominal pain, nausea, and constipation.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Bowel obstruction: Although less likely, a bowel obstruction could be a life-threatening condition that requires immediate attention. The patient's constipation and abdominal pain could be symptoms of a bowel obstruction.
- Chronic sympathicotonia: This is a rare condition characterized by increased sympathetic nervous system activity, which could potentially cause constipation, abdominal pain, and back pain. However, it is essential to consider this diagnosis to rule out any underlying neurological or systemic conditions.
- Rare diagnoses
- Other rare causes of constipation, such as Hirschsprung's disease or intestinal pseudo-obstruction, could be considered, but they are less likely given the patient's age and presentation.
- Spinal cord tumors or other neurological conditions could also cause constipation, back pain, and scoliosis, but these are rare and would require further investigation to diagnose.