Ueba Hiroaki, Moradi Natan, Erne Holger C, Gardner Thomas R, Strauch Robert J
Department of Orthopaedic Surgery, Columbia University Medical Center, New York, NY 10032, USA.
J Hand Surg Am. 2011 Dec;36(12):1959-64. doi: 10.1016/j.jhsa.2011.09.033.
To analyze the anatomy and contribution of the oblique retinacular ligament (ORL) to distal interphalangeal (DIP) joint extension force with varying angles of proximal interphalangeal (PIP) and metacarpophalangeal (MCP) joint flexion.
Forty fresh-frozen fingers were dissected. The fingers were mounted in a custom jig, and the force required to flex the DIP joint was assessed with the PIP joint flexed 0°, 30°, 60°, and 90° and with the MCP joint flexed 0°, 45°, and 90°. The force was measured in the intact specimen, and then all measurements were repeated following sectioning of the ORL and then the central slip.
The ORL was present on the radial and ulnar aspects of all but 2 fingers. The ORL tended to be the most robust in the ring finger. In the intact specimen, DIP flexion resistance force was maximum at 30° of PIP joint flexion and minimum at 90° of PIP joint flexion. There was a significant difference between the 90° position and all other positions of the PIP joint with respect to flexion force in the intact specimen. This meant that less force was required to flex the DIP joint at 90° of PIP joint flexion. Sectioning of the ORL revealed that it contributed 25% to the total force required to flex the DIP joint with the PIP joint at 0°, 31% at 30°, 18% at 60°, and 3% at 90° of flexion. The MCP joint position had no effect. Sectioning the central slip produced a significant increase in force required to flex the DIP joint at 90° of PIP joint flexion.
In this study, the ORL was usually present, and it contributed up to 30% of the passive resistance to DIP joint flexion. The intact central slip accounted for the decrease in DIP joint extensor tone at 90° of PIP joint flexion.
The ORL plays a small role in passively resisting DIP flexion.
分析不同近端指间关节（PIP）和掌指关节（MCP）屈曲角度下，斜支持韧带（ORL）对远侧指间关节（DIP）伸展力的解剖结构及作用。
解剖40个新鲜冷冻手指。将手指安装在定制夹具中，在PIP关节屈曲0°、30°、60°和90°以及MCP关节屈曲0°、45°和90°的情况下，评估使DIP关节屈曲所需的力。在完整标本中测量该力，然后在切断ORL，随后再切断中央束后重复所有测量。
除2个手指外，所有手指的桡侧和尺侧均存在ORL。ORL在环指中往往最为粗壮。在完整标本中，PIP关节屈曲30°时DIP屈曲阻力最大，PIP关节屈曲90°时最小。在完整标本中，PIP关节90°位置与所有其他位置的屈曲力之间存在显著差异。这意味着在PIP关节屈曲90°时使DIP关节屈曲所需的力较小。切断ORL后发现，在PIP关节屈曲0°时，它对使DIP关节屈曲所需的总力贡献为25%，30°时为31%，60°时为18%，90°时为3%。MCP关节位置无影响。切断中央束后，在PIP关节屈曲9 °时使DIP关节屈曲所需的力显著增加。
在本研究中，ORL通常存在，它对DIP关节屈曲的被动阻力贡献高达30%。完整的中央束导致PIP关节屈曲90°时DIP关节伸肌张力降低。
ORL在被动抵抗DIP屈曲中起较小作用。
