Unconventional pedicle spinal instrumentation. The Bombay experience

Area of Science:

• Spinal Surgery
• Orthopedic Instrumentation
• Biomechanical Engineering

Background:

• Retrospective analysis of spinal fusion patients (1986-1989).
• Evaluation of inexpensive, locally manufactured pedicle spinal instrumentation systems.
• Comparison with conventional, expensive instrumentation systems.

Purpose of the Study:

• To demonstrate the efficacy of simple, cost-effective pedicle instrumentation.
• To establish the importance of anterior column support for system effectiveness.
• To compare outcomes of unconventional versus conventional spinal instrumentation.

Main Methods:

• Review of 90 out of 102 patients with an average follow-up of 41 months.
• Assessment of implant failures, screw placement, fusion rates, infection, and neurological deficits.
• Evaluation of patient satisfaction and long-term benefits of anterior column grafting.

Main Results:

• Overall fusion occurred within 6.5 months.
• Forty-four of 467 screws (9%) failed, with 7 symptomatic patients; no plate failures.
• Anterior column grafting in burst fractures significantly reduced implant failures and loss of sagittal alignment.

Conclusions:

• Anterior column reconstruction is crucial for maintaining normal biomechanics and reducing implant failures.
• Pedicle screw failure does not always correlate with poor outcomes.
• Inexpensive, locally made systems are effective when biomechanics and load-sharing are properly understood and applied.