Calcaneocuboid stability: a clinical and anatomic study.

Injuries to the midtarsal joints are relatively uncommon and often unrecognized entities. Acute and chronic instability patterns to the calcaneocuboid joint can occur from such injuries. No previous determinations of normal calcaneocuboid laxity have been reported. Utilizing a previously described technique, stress radiographs were performed in human cadaveric specimens following serial sectioning of the ligamentous supports of the calcaneocuboid joint. Significant differences in calcaneocuboid gap and angle occurred between unstressed and stressed conditions. Cadaveric specimen testing determined that the dorsal and plantar calcaneocuboid ligaments both provide significant contributions to joint stability. Prior to defining pathologic states of joint laxity, normal ranges of stability must be determined. By more clearly defining normal stability of the calcaneocuboid joint and its ligamentous contributions, greater insight into the diagnosis and treatment of calcaneocuboid instability can be obtained.