1. Soft-Tissue Balancing of the Hip by Mark N. Charles, Robert B. Bourne, J. Roderick Davey, A. Seth Greenwald, Bernard F. Morrey, and Cecil H. Rorabeck J Bone Joint Surg Am Volume 86(5):1078-1088 May 1, 2004 ©2004 by The Journal of Bone and Joint Surgery, Inc.

2. Femoral offset is represented by the perpendicular distance “A” from the center of the femoral head to the long axis of the femur. Mark N. Charles et al. J Bone Joint Surg Am 2004;86:1078- 1088 ©2004 by The Journal of Bone and Joint Surgery, Inc.

3. The hip joint acts as a fulcrum balancing the force of body weight with the force generated by the hip abductors. Mark N. Charles et al. J Bone Joint Surg Am 2004;86:1078- 1088 ©2004 by The Journal of Bone and Joint Surgery, Inc.

4. Lateralization of the femoral shaft restores offset, reduces femoropelvic impingement, and increases abductor tension. Mark N. Charles et al. J Bone Joint Surg Am 2004;86:1078- 1088 ©2004 by The Journal of Bone and Joint Surgery, Inc.

5. Radiograph of a sixty-seven-year-old man with severe osteoarthritis of the right hip associated with superolateral migration of the femoral head and disruption of the Shenton line. Mark N. Charles et al. J Bone Joint Surg Am 2004;86:1078- 1088 ©2004 by The Journal of Bone and Joint Surgery, Inc.

6. Following total hip arthroplasty with a high-offset femoral component, the joint center has been displaced medially coincident with an increase in the abductor lever arm (A*) and a corresponding reduction in the joint reactive force. Mark N. Charles et al. J Bone Joint Surg Am 2004;86:1078- 1088 ©2004 by The Journal of Bone and Joint Surgery, Inc.

7. Increasing the length of the femoral neck or head increases the resting length of the hip abductors and thereby increases their contractile efficiency while concomitantly lengthening the abductor lever arm. Mark N. Charles et al. J Bone Joint Surg Am 2004;86:1078- 1088 ©2004 by The Journal of Bone and Joint Surgery, Inc.

8. Decreasing the neck-shaft angle reduces the height of the femoral head and thus the limb length while increasing offset. Mark N. Charles et al. J Bone Joint Surg Am 2004;86:1078- 1088 ©2004 by The Journal of Bone and Joint Surgery, Inc.

9. Standard compared with high-offset stems. Mark N. Charles et al. J Bone Joint Surg Am 2004;86:1078- 1088 ©2004 by The Journal of Bone and Joint Surgery, Inc.

10. It has been shown that a modular “offset” or “lateralized” liner (right) increases offset while preserving limb length. Mark N. Charles et al. J Bone Joint Surg Am 2004;86:1078- 1088 ©2004 by The Journal of Bone and Joint Surgery, Inc.

11. Radiographic assessment of limb-length discrepancy. Mark N. Charles et al. J Bone Joint Surg Am 2004;86:1078- 1088 ©2004 by The Journal of Bone and Joint Surgery, Inc.

12. A jig that measures femoral offset and limb length depends on a fixed reference point. Mark N. Charles et al. J Bone Joint Surg Am 2004;86:1078- 1088 ©2004 by The Journal of Bone and Joint Surgery, Inc.

13. The dropkick test is a maneuver whereby the hip is held in extension while the knee is concomitantly flexed to 90°. Mark N. Charles et al. J Bone Joint Surg Am 2004;86:1078- 1088 ©2004 by The Journal of Bone and Joint Surgery, Inc.

14. Stability is tested in full extension with concomitant maximal external rotation of the hip. Mark N. Charles et al. J Bone Joint Surg Am 2004;86:1078- 1088 ©2004 by The Journal of Bone and Joint Surgery, Inc.

15. Stability is tested in 90° of flexion of both the hip and knee with concomitant maximal internal rotation of the hip. Mark N. Charles et al. J Bone Joint Surg Am 2004;86:1078- 1088 ©2004 by The Journal of Bone and Joint Surgery, Inc.