A Rare Anatomical Finding of Undescribed Accessory Palmaris Longus in the Distal Forearm: A Case Report.

Upper limb muscle anomalies and their clinical implications have been described frequently in the literature reviews. In this article, we are presenting a case of aberrant forearm muscle that had not been described before, and could be considered as a palmaris longus muscle variation. A 24-year-old man presented to the emergency department, Hamad General Hospital, Doha, Qatar, with right forearm laceration with multiple cut structures for which he was admitted for exploration and repair. Intraoperatively, flexor digitorum superficialis of the third, fourth, and fifth digits, flexor carpi radialis, and palmaris longus were injured' and all of them were repaired. We noticed an aberrant muscle-which was also injured-that originated from the distal third of the radius on its medial aspect to insert into the palmar fascia; pulling this muscle's tendon resulted in tightening of palmar fascia' same as the palmaris longus. Along with the importance of deep knowledge of typical human anatomy, hand surgeons must be aware that an aberration from normal anatomy might be anticipated, to provide the best care to our patients.

Unusual Presentation of Extensor Tendon Rupture Caused by a Dorsal Wrist Synovial Cyst.

Synovial cysts are juxta-articular-fluid-filled collections that are lined by synovial cells, distinguishing them from a very close cystic lesion, which is the ganglion cyst. They usually present with pain and unpleasant appearance; here we present a case of wrist synovial cyst that caused extensor tendon rupture. A 50-year-old woman presented to our clinic with a cystic lesion on the dorsum of her wrist, with an inability to extend her index finger. The lesion was found intraoperatively engulfing the extensors of the index and causing a rupture. The cyst was excised and the tendon was reconstructed; pathology report confirmed the lesion as synovial cyst. Synovial cysts and ganglion cysts are two different entities but they have been used interchangeably in the literature; pathology is the only way to differentiate between them because they usually present with identical scenarios. None of them were reported to cause extensor tendon rupture, as presented in our article. Synovial cysts can cause rupture to extensor tendons if they arise from the sheath, and it is better to anticipate synovial cyst and remove it surgically before causing any further damage, if the lesion appeared to rise from the tendon sheath on further imaging.