An anomalous flexor digitorum sublimis to index finger with absent lumbrical

Painful, palpable and pathological: anomalous flexor digitorum superficialis brevis in the palm, comparative anatomical context, and an updated classification of anomalies of the flexor digitorum superficialis

“…The digastric anomaly has been the most commonly reported (Case, 1966; Das and Brown, 1975; Hayes, 1974; Kostakoglu et al, 1977; Mainland, 1927; Vichare, 1970). There are several reported cases of an intrinsic FDS brevis muscle co-existing with, and inserting into, an otherwise normal FDS tendon (Coenen and Biltjes, 1991; Fromont, 1895; Grant and Due, 1995; Sanger et al, 1991; Still and Kleinert, 1973).…”

Distally extended muscle belly of the flexor digitorum within the carpal tunnel: is it a risk factor for carpal tunnel syndrome?

“…The variant or anomalous muscle of FDS is usually categorized as a brevis type, arising from the transverse carpal ligament, which is muscle and tendon contained wholly within the hand, a digastric type, with continuity existing by way of a tendon between the hand and forearm muscle bellies, or a distally elongated muscle extending through the carpal tunnel (8,9). There are several case reports that discuss the variant or anomalous FDS presenting with palpable mass or CTS, most of which were the brevis or digastric types (8,(10)(11)(12). The distally elongated muscle of FDS extending through the carpal tunnel is the one dealt with in the present study.…”

Anomalous flexor digitorum superficialis muscle belly presenting as a mass within the palm

“…Anomalies of the flexor digitorum superficialis to the index finger are well documented (6)(7)(8)(9)(10). To date, three types of anomalies of the functional unit of the flexor digitorum superficialis that serves the index finger have been described by Probst and Hunter (11) and Christensen (12).…”