Distal tibial pilon fractures ( AO / OTA type B , and C ) treated with the external skeletal and minimal internal fixation method

Background/Aim. Distal tibial pilon fractures include extra-articular fractures of the tibial metaphysis and the more severe intra-articular tibial pilon fractures. There is no universal method for treating distal tibial pilon fractures. These fractures are treated by means of open reduction, internal fixation (ORIF) and external skeletal fixation. The high rate of soft-tissue complications associated with primary ORIF of pilon fractures led to the use of external skeletal fixation, with limited internal fixation as an alternative technique for definitive management. The aim of this study was to estimate efficacy of distal tibial pilon fratures treatment using the external skeletal and minimal internal fixation method. Methods. We presented a series of 31 operated patients with tibial pilon fractures. The patients were operated on using the method of external skeletal fixation with a minimal internal fixation. According to the AO/OTA classification, 17 patients had type B fracture and 14 patients type C fractures. The rigid external skeletal fixation was transformed into a dynamic external skeletal fixation 6 weeks post-surgery. Results. This retrospective study involved 31 patients with tibial pilon fractures, average age 41.81 (from 21 to 60) years. The average follow-up was 21.86 (from 12 to 48) months. The percentage of union was 90.32%, nonunion 3.22% and malunion 6.45%. The mean to fracture union was 14 (range 12–20) weeks. There were 4 (12.19%) infections around the pins of the external skeletal fixator and one (3.22%) deep infections. The ankle joint arthrosis as a late complication appeared in 4 (12.90%) patients. All arthroses appeared in patients who had type C fractures. The final functional results based on the AOFAS score were excellent in 51.61%, good in 32.25%, average in 12.90% and bad in 3.22% of the patients. Conclusion. External skeletal fixation and minimal internal fixation of distal tibial pilon fractures is a good method for treating all types of inta-articular pilon fractures. In fractures types B and C dynamic external skeletal fixation allows early mobility in the ankle joint.

This retrospective study involved 31 patients with tibial pilon fractures, average age 41.81 (from 21 to 60) years.The average follow-up was 21.86 (from 12 to 48) months.The percentage of union was 90.32%, nonunion 3.22% and malunion 6.45%.The mean to fracture union was 14 (range 12-20) weeks.There were 4 (12.19%)infections around the pins of the external skeletal fixator and one (3.22%)deep infections.The ankle joint arthrosis as a late complication appeared in 4 (12.90%)patients.All arthroses appeared in patients who had type C fractures.The final functional results based on the AOFAS score were excellent in 51.61%, good in 32.25%, average in 12.90% and bad in 3.22% of the patients.Conclusion.External skeletal fixation and minimal internal fixation of distal tibial pilon fractures is a good method for treating all types of inta-articular pilon fractures.In fractures types B and C dynamic external skeletal fixation allows early mobility in the ankle joint.

Introduction
In contrast to the rotational mechanisms that result in malleolar fractures and fracture-dislocations of the ankle, distal tibial pilon fractures typically result from high-energy axialloading mechanisms.Distal tibial pilon fractures include extraarticular fractures of the tibial metaphysis and the more severe intraarticular tibial plafond or pilon fractures.The clinical manifestation of this fractures difference is the generation of osteochondral fracturing, comminution and displacement of the weight-bearing articular portion of the tibial plafond and distal tibial metaphysis, as well as the development of marked swelling, blistering and devitalization of the surrounding soft-tissue envelope typically identified in tibial pilon fractures.These fractures are estimated to comprise 3% to 10% of all tibia fractures and less than 1% of lower extremity fractures.These high energy injuries, usually caused by falls from heights or motor vehicle accidens, are often open fractures and they are frequently associated with additional trauma in other areas of the body [1][2][3] .They are one of the most challenging injuries in orthopaedic traumatology 4 .Several treatment methods are recommended for the treatment of these injuries including external skeletal fixation, intramedullary nailing, and plate fixation [5][6][7][8] .The aim of this study was to estimate efficacy of a treatment of a distal tibial fracture (AO type B and C) using the method of external skeletal fixation combined with minimal internal fixation.
The high rate of soft-tissue complications associated with primary open reduction, internal fixation (ORIF) of distal tibial pilon fractures led to use of external skeletal fixation, with limited internal fixation as an alternative technique for definitive management.Our aim was to analyze original results of distal tibial pilon fractures treatment using the external skeletal and minimal internal fixation method.

Methods
The patients with distal tibial fracture were operated on at the University Orthopedic and Traumatology Clinic, Niš.The patients with intra-articular fractures (AO/OTA types B and C) were operated on using the method of external skeletal fixation and minimal internal fixation.To perform minimal internal fixation, screws and K-wires were used.In patients with types B and C fractures, rigid external skeletal fixation was transformed into dynamic external skeletal fixation 1.5 month later.All fractures were classified according to the AO/OTA classification 9 .The Gustilo-Anderson classification system was used for all open fractures 10 .To perform external skeletal fixation, a Mitkovic's unilateral external skeletal fixator was used.To analyze the final functional results, the AOFAS scoring system was used 11 .

Results
This retrospective study involved 31 patients with distal tibial pilon fractures.According to the AO/OTA classification, 17 patients had fractures type B and 14 patients fractures type C (Figures 1-5 and 6-9 respectively).The average age was 41.81 (21-60) years, and there were 20 male patients and 11 female patients.Open fractures appeared in 11 (35.48%)patients.A total of 10 (32.25%) fractures were caused by car accidents, 14 (45.16%) by falls from heights, whereas 7 (22.58%)fractures appeared under different circumstances, such as in accidents at work, falls from stairs, or as a result of slip and fall accidents on an even surface.The average follow-up of the patients was 21.86 (12-48) months.There were 28 (90.32%)unions, 1 (3.22%) nonunions and 2 (6.45%) malunions.The mean to fracture union was 14 (range 12-20) weeks.As regards complications, infection around the pins of the external skeletal fixator appeared in 4 (12.19%) and deep infections appeared in 1 (3.22%) patients.Ankle joint arthrosis as late complication appeared in 4 (12.90%)patients.All arthroses appeared in patients with fractures type C. According to AOFAS, the final functional results were excellent in 16 (51.61%)patients, good in 10 (32.25%), average in 4 (12.90%)patietns and bad in 1 (3.22%) cases.All the patients were operated on as urgent cases, immediately after hospitalization.

Discussion
In the decade 1980 to 1990 numerous publications favoured the approach to distal tibial fractures that included external skeletal fixation as primary stabilization, with or without some form of limited internal fixation.This was in reaction to numerous complications that were observed previously following ORIF 12 .High-energy distal tibial fracture with soft tissue compromise remains a treatment dilemma.Clinical series from the 1980 and 1990 using primary ORIF had complications rates of greater than 50%, most related to soft-tissue complications and infections, including amputation rates as high as 17% 13,14 .The high rate of soft-tissue complications associated with primary ORIF of pilon fractures led to use of external skeletal fixation, with limited internal fixation as an alternative technique for definitive management.Hybrid external skeletal fixation with limited open reduction has proved to be a safe, reproducible, and effective treatment modality for this complex fracture 15 .Distal tibial fractures are serious injuries which most frequently appear in car accidents or in falls from heights.There is no universal method in treating these fractures.The most frequent methods are operation, open reduction and internal fixation, intramedullary fixation, plate fixation, external skeletal fixation.Some authors recommend a two-step procedure.After applying the external skeletal fixation, an internal plate fixation is performed [6][7][8][9][10][11][12][13][14][15][16][17][18] .We used the external skeletal fixation as one-step procedure in the treatment of distal tibial pilon fracture.We presented the results of distal tibia fracture treatment using the method of external skeletal fixation combined with minimal internal fixation (AO/OTA fractures types B and C).Studies show that minimal internal fixation and external skeletal fixation achieve good results in the treatment of these fractures.A higher percentage of superfi- cial infections around the pins does not affect the final outcome of the treatment 19 .Bone 1 also describes satisfactory results in the application of this method.In fractures type B and C, it is necessary to achieve fracture reduction and articular tibial surface reconstruction.Fixation by means of screws and K-wires is open and minimal.External skeletal fixator pins are placed, 2 in the proximal fragment, and 2 in the foot.One pin is placed in the calcaneus, the other in the I metatarsal bone.After that, the external skeletal fixator frame with clamps and carriers of the clamp placed.In this way, rigid fracture fixation is achieved, and it transforms into dynamic fixation 6-week post-surgery, which allows early ankle joint mobility 20 .A dynamic external skeletal fixation is placed on an already existing external skeletal fixator construction with additional carriers of the clamp and clamps.This system for external skeletal fixation is suitable for additional interventions, such as fracture position correction while the apparatus is carried.Studies describe this method of treatment as definitive or temporary method, after which intramedullary or plate fixation of fracture will be per-formed 21 .Our experience in the treatment of these fractures as definitive method and our results are very encouraging, giving us right to consider this method suitable for treating all types of distal tibial pilon fractures.It is important to emphasize that these fractures are considered as urgent, and they should be treated urgently.Urgent surgical intervention reduces the possibility of complications.

Conclusion
External skeletal fixation of distal tibial and pilon fractures as one-step procedure is a good method for treating all types of fractures.In fractures types B and C, dynamic external skeletal fixation allows early mobility in the ankle joint.