computer-assisted navigation in total knee replacement: results of an initial experience in...

Computer-Assisted Navigation in Total Knee Replacement: Results of an Initial Experience in Thirty-five Patients

by S. David Stulberg, Peter Loan, and Vineet Sarin

J Bone Joint Surg AmVolume 84(suppl 2):S90-S98

November 1, 2002

©2002 by The Journal of Bone and Joint Surgery, Inc.

The main components of an image-free navigation system for total knee replacement include a system equipment trolley and isolation transformer; an infrared camera system; infrared

transmitters; a computer workstation, monitor, keyboard, and mouse; and a foo...

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.

The femoral screw is inserted into the medial cortex approximately 10 cm proximal to the knee joint.

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.

The tibial screw is inserted into the anterior-medial cortex approximately 8 cm distal to the tibial plateau.

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.

Figs. 4-A and 4-B The center of the femoral head is determined with use of a kinematic registration technique.

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.

The center of the ankle joint is determined with use of a metal plate that contains an adapter to hold a rigid body to the foot with a rubber band.

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.

With the metal plate attached, the ankle joint is then flexed and extended.

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.

The kinematic center of the knee joint is determined by slowly flexing and extending the knee from 0° to 90°.

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.

The level of tibial resection is measured from the deepest point on the least damaged side of the plateau, which is registered with a probe to which the diode-containing rigid body is attached.

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.

Figs. 9-A and 9-B The size and rotation of the femoral component is calculated with registration of the posterior surfaces of the medial and lateral femoral condyles at the points farthest from

the anterior femoral cortex.

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.

Figs. 10-A and 10-B The anterior femoral cortex is palpated with the probe directly above the center of the trochlea.

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.

Figs. 11-A and 11-B The epicondylar axis is determined with palpation of the medial and lateral epicondyles with the probe.

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.

Figs. 12-A, 12-B, and 12-C The center of rotation of the ankle joint is confirmed with palpation of the medial and lateral malleoli and the anterior midpoint of the ankle.

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.

The preoperative limb alignment (load line) in the frontal and sagittal planes, the medial-lateral stability in extension, and the range of motion can be recorded once the registration process is

complete.

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.

The preoperative limb alignment in the frontal plane was determined on two separate registrations.

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.

When the alignment was determined on a model with use of equipment identical to that used in the clinical study, there was very little variation between the first and second registrations.

S. David Stulberg et al. J Bone Joint Surg Am 2002;84:S90-S98

©2002 by The Journal of Bone and Joint Surgery, Inc.