Cleland's ligaments: an anatomic study

The anatomy and function of Cleland's ligaments--thought by the authors to require clarification because of the conflicting anatomic descriptions in the literature--are reviewed. A statistical representation of the structure of these ligamentous bundles was derived from the study of 16 fixed human cadaveric digits and five fresh cadaveric digits, all from different patients. The results demonstrate a large variation in anatomy. However, this anatomic heterogeneity is not indicative of an equally varied function. In general, it was found that the majority of Cleland's ligaments traversed a great distance adherent to the skin before actually inserting in the dermis. Over one-third of the dorsal fibers demonstrated a multiplanar organization, fanning out before inserting into the skin. In contrast, the ventral fibers did not fan out before inserting into the skin. Excision of these ventral fibers revealed a separate "ledgelike" plane of fibers arising from the fibrous flexor sheath and running in a straight line perpendicular to the long axis of the digit. A branch of the digital nerve was found to pierce this ligamentous layer in the majority of digits studied. Unlike those of previous reports, the results of the present study suggest that the ligaments have a constant function of anchoring the skin of the digit on both the dorsal and ventral aspects, thereby preventing the displacement of skin during flexion of the digits. All previous studies failed to make this conclusion. The anatomic relationship to the digital neurovascular bundle also suggests that Cleland's ligaments may stabilize the digital vessels during flexion. In conclusion, Cleland's ligaments are highly functional structures and are essential for normal cutaneous stability during digital movements.