Open Fractures of the Tibia

Open Fractures of the Tibia

25% of tibial shaft fractures can be open. Open fractures can lead to complications including wound problems, osteomyelitis, nonunions, and infected nonunions. The treatment of open fractures of the tibia can be challenging. A lot of the concepts are not black and white; they may be in the grey zone. We don’t know the best time for debridement. We don’t know what the optimal irrigation solution is and what the optimal pressure for the fluid is. We don’t know for sure the ideal duration of giving antibiotic prophylaxis, but we know that it is important to give the appropriate antibiotics early and do meticulous debridement. We know that the IM rod is better than the plate fixation or external fixator, and the result of the reamed IM rod or unreamed IM rod is the same. We need to close or cover the wound before 1 week and the vac can be used provisionally when we cannot close the wound, primarily at the optimal time. A grade I fracture is less than 1 cm. a grade II fracture is 1-10cm. A grade III fracture is more than 10 cm, and there is contamination. Grade III fractures are divided into three types. Grade IIIa fractures require adequate tissue for closure (or skin graft). Grade IIIb fractures require extensive periosteal stripping and the patient will need a flap (rotational or free flap). Grade IIIc fractures have a vascular injury that requires repair or amputation. The relative indication for amputation is warm ischemia for more than 6 hours, absent plantar sensation and severe ipsilateral foot trauma.

The most predictive factor for amputation is the severity of the soft tissue injury in the ipsilateral extremity. When comparing limb salvage versus amputation, the patient’s outcome is generally the same at 1-5 years. Lack of plantar sensation does not predict poor outcome after limb salvage. Segmental fractures are Grade III fractures, even if the open fracture is 1 cm. The ideal irrigation solution and the pressure used to controversial. Timing of the initial debridement is controversial. Irrigation and debridement within 6 hours was the gold standard in the past. Debridement is performed as a priority procedure no later than the morning after admission. There is no difference in infection rate for a patient who has the initial surgery before or after 6 hours, including patients with Type III open fractures. More than 40% of the patients usually wait longer than 6 hours for their initial surgery after arrival at the hospital. Delayed surgery for less severe fractures is acceptable as long as the debridement is done as a priority the following day. Unless there is a gross contamination, evidence is not clear as to when is the best time for the debridement. It seems like giving the patient antibiotics promptly is more important than the time of debridement. The preferred solution is normal saline and low pressure irrigation. Low pressure lavage may reduce reoperation rates due to infection, nonunions, and wound healing problems. Normally the tradition is to use 3, 6, and 9 liters of solution for Type I, Type II, and Type III open fractures (just recommendations). There is increased risk of wound healing with antibiotic solution. Meticulous irrigation and debridement of open fractures is important in decreasing the infection risk. Prophylaxis should be started as soon as possible. All patients with open fractures should receive first generation Cephalosporin’s that will cover gram-positive bacteria. You can give penicillin for farm injuries and clostridia prone wounds. You will give clindamycin if there is a penicillin allergy. In Type III open fractures, add aminoglycoside, such as gentamicin. It was found that local antibiotics delivery at the site of injury decreased the infection risk, such as cement beaded loaded with antibiotics. Antibiotic should be given within 3 hours of the time of injury (preferably given as soon as possible). There is reduction of 59% of acute infection in patients with open fractures treated with antibiotics. The infection rate is 1.6 times greater if antibiotics are given after 3 hours. Type I and Type II open fractures require antibiotic coverage for 24 hours after wound closure. For Type III open fractures, antibiotic administration should be given for a period of 72 hours after the injury and no more than 24 hours after wound closure. After the initial debridement, the patient will need staged debridement within 24-48 hours. There is a reduction infection rate, acute and chronic, for Type III open fractures with the use of systemic antibiotics and aminoglycoside cement beads compared with antibiotics alone. This combination of antibiotics lowers the infection rate for any open tibial fracture that is treated with an IM rod. Its affect is more noticed in Type III injuries. Plating of open fractures may cause chronic infection and infected nonunion. The healing time is doubled with plated open fractures. The IM rod resulted in a better alignment and lower reoperation rate than using external fixator. Also, no difference in the infection rate between the IM rod and the external fixator. You can use a reamed nail or an unreamed nail. They both have a comparable result and no difference in the outcome.

When reaming, you can use a bigger rod that provides better stability. Reamed nailing is superior in closed tibial fractures, but it is not superior in open tibial fractures. Reaming can cause increased pressure and disruption of the endosteal blood supply, can cause thermal necrosis and fat embolism with increased intramedullary risk of infection. The unreamed rod uses smaller nails and results in less stability but preserves the endosteal blood supply. Unreamed IM tibial rod appears to have a shorter time to union and fewer incidence of knee contractures when compared with circular wire external fixator. Nowadays, more and more orthopedic surgeons are using reamed nails for open fractures of the tibia. If you have a spiral fracture of the distal 1/3 of the tibia, you will need to get a CT scan of the ankle to identify a posterior malleolar fracture, which should be fixed before insertion of the IM rod. There is a lack of evidence to support the value of external fixator over the IM rod in open factures of the tibia. Due to patient discomfort, the high incidence of pin tract infection and loss of alignment, external fixator should not be used as a definitive fixation. Use external fixator temporarily (less than 4 weeks) and replace it with a rod in about 14 days. External fixator may be utilized for severely contaminated open fractures. Tibial fractures treated with a shorter duration of external fixator has reduction of the infection risk by 80%. When there is a shorter interval between removal of the external fixator and insertion of the IM rod of the tibia, there is a reduction of the risk of infection by 85%. In less severe soft tissue injuries, you do primary closure without tension. In cases of delayed closure, soft tissue coverage should be done within 7 days. Soft tissue coverage beyond 7 days will increase the infection. There is no difference in the incidence of infection in patients who had primary closure and delayed closure of the wound. It is recommended to do primary closure for Type I, Type II, and Type IIIa fractures with tension free closure and after timely antibiotic prophylaxis and adequate debridement. Intraoperative culture after debridement has no value. It does not predict future infection. In the upper 1/3 of the tibia, you can treat it by a medial gastrocnemius flap. In the middle 1/3 of the tibia, you can treat it by a soleus rotational flap. The use of a free flap for soft tissue coverage was less likely to have wound complications than the use of a rotational flap. The zone of injury may be larger than expected, and it may include the rotated muscle flap. The negative pressure wound therapy (the vac) is used frequently. The vac provides provisional coverage for wounds where the physician cannot do primary closure. There is decreased infection rate when using the vac. The vac is used for coverage after the initial debridement of the open fracture until the definitive coverage is done. It is a good temporizing dressing and can also be used in fasciotomy wounds. The vac promotes local wound healing. Bone morphogenetic protein (BMP2) decreases the need for secondary surgery and is used in acute open tibial fractures treated with IM rod.