Use of Blocking Screws in Supplementary Way to Interlocking Nail in the Management of Non-Diaphyseal Tibial Fractures

Abstract

Background:proximal and distal fractures of tibia tend to undergo malalignement when treated with intramedullary nails or functional braces. Blocking or “Poller” screws are a particularly useful technique to help guide the nail correctly. This technique involves placing a blocking screw, drill bit, or K-wire to force the reamer and then the nail into the proper path.

Aim of the study: The aim of this study wasto evaluate the role of blocking (poller) screws in preventing malalignment after interlocking nailing of non-diaphyseal tibial fractures.

Patients and methods:12 patients suffering from metaphyseo – diaphyseal tibial fractures were treated by intramedullary nailing with blocking screws in Department of Orthopeadic surgery at Zagazig University and el Zaitoun Specialized Hospital.Fracture classification was done according to AO surgery reference and of soft tissue injury according to Tcherne classification for open fractures. Following removal of sutures (2 weeks), patients were seen in the clinic every month until union was achieved clinically and radio graphically and after the union, they were also seen at 6 month.

Results:Two of the twelve patients had postoperative fracture varus angulation that was less than 5°, they had score excellent, and one patient had postoperative valgus angulation of about 3° who achieved score good.  Healing time was affected by some factors that causes delayed healing time (22-24 weeks). All the twelve patients (100%) achieved union at average time twenty weeks (ranging from 16 to 24 weeks). Five patients showed delayed union 24 weeks, 2 patients were over fifty years showed complete union at 20 and 24 weeks respectively. Delayed union was not related to the technique of poller screws or the concept itself as all the other younger patients or medically free patients healed at shorter time with no complications.

Conclusion:This study demonstrated that the overall results of our patients were studied in correlation to Olerud & Molander score, where we have 5 cases having excellent score (42%) & 7 cases have good score (58%). There is some factors that affect the overall result of our cases as type of fracture, smoking, mode of trauma, patient general condition, type of intramedullary nail used and its application, postoperative range of motion of knee and ankle joint.