Clinical Outcome Of Posterolateral Approach For Treatment Of Trimalleolar Fracture A Retrospective Study

Background:Trimalleolar fractures are common injuries and usually results from rotational ankle injuries.The posterior malleolar fractures are important components of ankle fractures and it plays an integral role in ankle joint stability through its anatomical relationship with the posterior inferior tibiofibular ligament(PITFL).Objective:The goal of this study was to analyze the clinical outcome of posterolateral approach for treatment of trimalleolar fracture and to compare the results of Screw versus plate for the fixation of posterior fragment.Methods:This was a retrospective study which included 45 cases of trimalleolar fractures who were treated surgically at Zhong Da hospital affiliated to southeast university from June 2012 to June 2017.Among which 15 were male patients and 30 were female patients.All the procedures were performed via a posterolateral approach to fix the lateral and posterior malleolar fragments.For the posterior fragment,25 patients were internally fixed with screw and 20 were fixed with plate.The mean age of patients with screw group was 52.1±15.2(range 20-76)years old whereas for plate group was 50.2±14.2(range 23-78)years old.The mean follow-up in the screw group was 40.0±16.39 months(range 18-64 months)and for plate group was 33.95+16.51 months(range 15-62 months).Radiographic evaluation was performed immediately and every four weeks after the surgery.American orthopedic foot and ankle society(AOFAS)score and Olerud-Molander score were used as the main functional outcome measurements at the final follow up.Results:In this study,two groups were compared based on day of injury(DOI)to day of surgery(DOS),skin incision,operative time,blood loss,hospital stay and bone union. There was no significant difference observed in efficacy of the posterolateral approach among the both groups with regard to age of the patients,p>0.668 and DOI to DOS,p>0.295.Also skin incision,operative time,blood loss volume and hospital stay duration had no difference significantly among both the groups.The mean follow-up period for screw group was 40.0+16.39 months(range 18-64 months)and for plate group was 33.95+16.51 months(range 15-62 months).Implant loosening,displacement and breakage of implant was not seen in any of the cases.The mean time of primary bone union was 5.20+1.38 months(range 3-7 months)for screw group and 5.00+1.12 months(range 3-7 months)for plate group.The surgical outcome was evaluated by AOFAS and Olerud-Molander score on follow-up visits.The mean AOFAS score for screw group was 87.70±10.99(Excellent-6,good-14)and Olerud-Molander score was 91.56±11.73((Excellent-19,good-3)whereas for plate group,AOFAS score was 85.85±13.09((Excellent-7,good-9)and Olerud-Molander score was 90.30+12.21((Excellent-11,good-8).There was no clinical difference in AOFAS score and Olerud-Molander score among both the groups(P>.425 and P>.471).Conclusions:The posterolateral approach provides an optimal exposure for the fixation of the ankle fracture and can fix the posterior malleolus and lateral malleolus at the same time.This approach can be performed with minimal blood loss and with less skin incision.In our study,good(AOFAS and Olerud and Molander score)and equivalent results were obtained using screws or plate for fixation of posterior malleolar fracture.So,we concluded this approach can fix both fractures at the same time and obtain good mechanical stability.