title: Occult Isolated Articular Branch Cyst of the Lateral Plantar Nerve.
abstract: We present the first known case of cyst fluid localized to an articular branch without involvement of the larger parent nerve. During a routine tarsal tunnel decompression in a patient with fluctuating plantar foot symptoms and "normal" magnetic resonance imaging findings, we identified cyst fluid within an articular branch of the lateral plantar nerve to the subtalar joint. Our incidental intraoperative discovery was corroborated by retrospective review of the magnetic resonance images. Although we do not know whether this cyst was responsible for the patient's complaints, we believe this finding represents a snapshot into the life cycle of intraneural ganglion cysts: either the "birth" of an ultra-early one or the remnant of a once larger one. Both interpretations are consistent with the unifying articular theory and add further insight into the dynamic phases of the progression of intraneural ganglion cysts.
authors.affiliation: Research Fellow, Department of Neurologic Surgery, Mayo Clinic, Rochester, MN.
authors.forename: Nikhil
authors.initials: N
authors.lastname: Prasad
authors.affiliation: Professor, Department of Neurologic Surgery and Radiology, Mayo Clinic, Rochester, MN.
authors.forename: Kimberly K
authors.initials: KK
authors.lastname: Amrami
authors.affiliation: Research Assistant, Department of Neurologic Surgery, Mayo Clinic, Rochester, MN.
authors.forename: Kivanc
authors.initials: K
authors.lastname: Yangi
authors.affiliation: Professor and Chair, Department of Neurologic Surgery, Mayo Clinic, Rochester, MN. Electronic address: spinner.robert@mayo.edu.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Spinner
mesh_terms: D004576:Electromyography / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D045888:Ganglion Cysts / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D033162:Incidental Findings; D007431:Intraoperative Complications / Q000000981:diagnostic imaging / Q000601:surgery; D008279:Magnetic Resonance Imaging / Q000379:methods; D008875:Middle Aged; D011300:Preoperative Care; D018570:Risk Assessment; D013380:Subtalar Joint / Q000000981:diagnostic imaging / Q000601:surgery; D013641:Tarsal Tunnel Syndrome / Q000000981:diagnostic imaging* / Q000601:surgery*; D013979:Tibial Nerve / Q000000981:diagnostic imaging / Q000601:surgery*; D016896:Treatment Outcome; D018608:Ultrasonography, Doppler / Q000379:methods
keywords: intraneural ganglion cyst; lateral plantar nerve; tibial nerve