Spiral fractures of tibia are relatively difficult to nail in anatomical or close to anatomical position. The main reason very likely lies in fracture configuration itself. As the spiral fractures have only one degree of freedom, they will either reduce perfectly or will not reduce at all.
Nailing of spiral fracture requires at least one poller screw in the fragment with broader medullary canal. If we want to apply epicentric/non-epicentric concept, than we need at last two poller screws. One on the each side of the fracture, ideally more or less at the same distance from the fracture. Interestingly, epicentric concepts is in our practice related to a significant lower pain postoperatively, which we can only explain at the moment by lower shearing at the fracture side. Any other explanations are more than welcome.
In this case I will be presenting a very low spiral distal tibia fracture which was treated with a nail and three poller screws following epicentric theory of fracture fixation. Whilst initial reduction was helped by a reduction clamp to enable insertion of the guide wire, definitive fixation after exchanging the nail for the shorter one, was not. We feel strongly that only poller screws are responsible for it.
It is worth mentioning that the nailing was done through suprapatellar approach which made nailing and the poller screws insertion much easier comparing to the standard infrapatellar approach. Suprapatellar approach for tibial nailing is certainly something worth considering particularly for any complex tibial fractures.
CT scan showed that the lowest part of the proximal spiral is at the back of the distal tibia. Knowledge we gain in previous poller screw applications certainly helped in preoperative planning. What we learnt is that for spiral fractures, poller screws don’t have to be strictly ap and laterally oriented. Additional fact is that usually one poller screw is enough for a spiral fracture unless the fracture is older than a couple of weeks or the fragment is relatively short, meaning that the length of the nail path in the fragment will be short and the fragment will not un-tilt after initial tilt after the nail will engage the poller screw.
Knowing all the above we decided to put a poller screw in an oblique plain starting lateral and proximal and ending posterior and medial. Initial one was put too posterior and would not let the nail to enter the distal fragment posteriorly and was hence repositioned and moved anteriorly. The nail had to go posteriorly to the poller screw as otherwise there will be no benefit from poller screw application. Additional poller screw distally in ap direction helped straighten the fragment.
Proximal poller screw to the fracture was a standard ap poller screw. All screws were 4 mm locking screws from the nailing system as they are not as rigid as 5 mm screws from the same set and will deform and not likely break the bone. Not likely.
Patient postoperatively did have pain but it was less than what we usually see after tibia nailing. Because of the uncertainty about the construct stability will keep him non-weight bearing for 6 weeks or at least until the next follow up and X-ray check. As soon as there will be some callus formation will allow weight bearing as tolerated.
Mr Matija Krkovic, MD, PhD
I am Consultant Orthopaedic Trauma Surgeon with special interest in Limb reconstructions and bone infections.