# A Rare Case of Congenital Absence of Flexor Digitorum Profundus in the Index Finger

## TL;DR

A 19-year-old man had a rare case of missing flexor digitorum profundus tendon in his index finger, discovered during treatment for burn-related hand issues.

## Contribution

Reports a rare congenital absence of FDPt in the index finger, adding to the limited existing literature on this condition.

## Key findings

- Congenital absence of FDPt in the index finger was confirmed via MRI with no compensatory tendon anomalies.
- The patient had reduced distal phalange girth and absent distal digital crease in the affected finger.
- The case highlights the importance of thorough preoperative assessment to avoid misinterpretation of anatomical variants.

## Abstract

Congenital anomalies of the flexor tendons in the human hand are rare, and those of the flexor digitorum profundus tendon (FDPt) are even rarer. Our search of the literature unearthed only eleven studies, with only one other report of absent FDPt in the index finger. This study presents a case of a 19-year-old male with congenital absence of FDPt in the index finger, discovered incidentally while seeking treatment for post-burn flexion contractures in the ring and little finger. The girth of the distal phalange was reduced compared to that of the opposite finger, and the distal digital crease was absent. Magnetic resonance imaging confirmed the diagnosis, with no compensatory tendon anomalies. The patient underwent release of post-burn flexion contractures with multiple Z-plasties and refused treatment for the index finger. These anatomic variants may cause misinterpretation during the evaluation of a patient with injuries. This case focuses on the need for thorough preoperative assessment.