Table 2 Previous studies on anatomical variations and nomenclature of the accessory flexor digiti minimi muscles of the foot
Author | Year | Place | Study design | Name | Origin | Insertion | Function | Innervation | Clinical relevance and significance |
|---|---|---|---|---|---|---|---|---|---|
Asomugha | 2005 | Nigeria | Cadaver (left foot) | Accessory FDM | Tendon of tibialis posterior | The middle phalanx of the fifth toe | Flexion of the fifth toe | Medial plantar nerve | It helps the FDM muscle and causes abnormal swelling in MRI and ultrasound |
Rana | 2006 | India | Case | FDM muscle | Plantar surface of base of the fifth metatarsal bone and the sheath of the peroneus longus tendon | ADM muscle, distal phalanx, plantar deep transverse metatarsal ligaments | It may take part in the biomechanics of the FDM muscle | Lateral plantar nerve | Surgeons should be aware of the inadvertent injury and compression of adjacent nerve |
Mehta | 2011 | India | Cadaver | FDMB | The tendon of the tibialis posterior, the fifth metatarsal bone, or the fourth metatarsal bone | It inserts into the fifth toe | Flexion of the fifth toe | N/A | These anatomical variances mitigate the occurrence of post-operative risks and complications, prompting surgeons to meticulously strategize their surgical approaches |
Lucaciu | 2007 | Canada | Cadaver (76,Female,Case) | Accessory FDMB muscles | The tendons of the two accessory FDM muscles had merged into a single tendon before the 5th MTP joint | The middle phalanx of the 5th toe | Two accessory FDM muscles seemed to have compensated for the absent section of the FDB muscle | N/A | Biomechanical compensation likely played a role in guiding myotomal cell migration during embryogenesis and could have helped explain the occurrence of muscular variants |
Buschbacher | 1999 | USA | 205 volunteers | FDMB | The normal variance between the medial and lateral branches was a 3.5Â ms elevation of the lateral latency over the medial latency or a medial latency within 0.3Â ms of the lateral latency | The maximum threshold for inter-limb latency divergence was either 1.8 or 1.5Â ms | Side-to-side variability | The conduction of tibial nerve | A correlation was observed between advancing age and a decline in both amplitude and area |
Edema | 2020 | Japan | Cadavers (52) | FDMB | The peroneus longus tendon | Additional band: anterior frenular ligament, ODM | N/A | N/A | These variations and functions seem to be linked to a challenging diagnosis during the initial clinical assessment |
Knellwolf | 2019 | Australia | 12 healthy subjects (18–40 years) | FDMB | N/A | N/A | FDMB displayed a response to passive flexion and abduction of the fifth MTP | Tibial nerve | Spindle endings in the intrinsic muscles of the foot contribute valuable proprioceptive information during free standing |
Karip | 2021 | Turkey | Cadaver | FDMB | Base of the fifth metatarsal bone | Base of the fifth proximal phalanx | The normal function of the lateral plantar aspect | N/A | The ADM and FDMB muscles were favored choices in the treatment of certain diseases as flaps |