Research Article| Volume 33, ISSUE 8, P729-734, October 2002

Do type B malleolar fractures need a positioning screw?


      Type B malleolar fractures (AO/ASIF classification) are usually stable ankle joint fractures. Nonetheless, some show a residual instability after internal fixation requiring further stabilization. How often does such a situation occur and can these unstable fractures be recognized beforehand?
      From 1995 to 1997, 111 malleolar fractures (three type A, 90 type B, 18 type C) were operated on. Seventeen out of 90 patients (19%) with a type B fracture showed residual instability after internal fixation (one unilateral, four bimalleolar and 12 trimalleolar fractures). Five of these patients showed a dislocation in the sagittal plane (anteroposterior) clinically or on the radiographs, five a dislocation in the coronal plane with dislocation of the tibia on the medial aspect of the ankle joint, and four an incongruency on the medial aspect of the joint. In three cases, no preoperative abnormality indicating instability was found. The fractures were all fixed using an additional positioning screw.
      In 11 patients, the positioning screw was removed after 8–12 weeks, in six patients removal was performed after 1 year along with removal of the plate. All 17 patients were reviewed 1 year after internal fixation, 16/17 showed a good or excellent result with identical or only minor impairment of range of motion of the ankle joint.
      Conclusion: Unstable ankle joints after internal fixation of type B malleolar fractures exist. Residual instability most often occurs after trimalleolar fractures with initial joint dislocation. Treatment with an additional positioning screw generally produced a satisfactory result.
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      1. Müller ME, Nazarian S, Koch P, Schatzker J. The comprehensive classification of fractures of long bones. Berlin: Springer, 1990.

      2. Müller ME, Allgöwer M, Schneider R, Willenegger H. Manual of internal fixation. 3rd ed. Berlin: Springer, 1991.

        • Heim D.
        • Schwab M.
        Qualitätssicherung: Die AO Dokumentation am peripheren Spital.
        Swiss. Surg. 1999; 5: 271-275
      3. Heim UFA, Pfeiffer KM. Internal fixation of small fractures. 3rd ed. Berlin: Springer, 1988.

      4. Danis R. Théorie et practique de l’ostéosynthese. Paris: Masson et Cie, 1947.

        • Heim D.
        • Heim U.
        • Regazzoni P.
        Malleolarfrakturen mit Gabelsprengung—Erfahrungen mit der Stellschraube.
        Unfallchirurgie. 1993; 5: 307-312
        • Heim U.F.A.
        Die Risse der membrana interossea bei Malleolarfrakturen. Ihre Bedeutung für Klassifikation und Operationstechnik.
        Hefte. Unfallheilk. 1983; 165: 247-250
      5. Heim U. Malleolarfrakturen mit Gabelsprengung. Doctoral Thesis. Switzerland: University of Basle, 1992.

      6. Schmid-Giovanoli C. Die Zerreissung der Membrana interossea bei Malleolarfrakturen. Ihr Vorkommen und ihre biomechanische Bedeutung. Doctoral Thesis. Switzerland: University of Zürich, 1980.

        • Xenos J.S.
        • Hopkinson W.J.
        • Mulligan M.E.
        • et al.
        The tibiofibular syndesmosis.
        J. Bone Jt. Surg. 1995; 77A: 847-856
        • Engelbrecht E.
        • Engelbrecht H.
        • Huynh P.L.
        Erfahrungen mit dem Syndesmosehaken bei tibiofibularen Bandverletzungen.
        Chirurg. 1984; 55: 749-755
        • Farhan M.J.
        • Smith T.W.D.
        Fixation of diastasis of the inferior tibiofibular joint using the syndesmosis hook.
        Injury. 1985; 16: 309-311
        • Yde J.
        • Kristensen K.D.
        Inferior tibiofibular diastasis treated by staple fixation.
        J. Trauma. 1981; 21: 483-485
        • Peter R.E.
        • Harrington R.M.
        • Henley M.B.
        • et al.
        Biomechanical effect of internal fixation of the distal tibiofibular syndesmotic joint: comparison of two fixation techniques.
        J. Orthop. Trauma. 1994; 8: 215-219
      7. Ledermann M. Die Dynamik der distalen tibiofibularen syndesmose. Postdoctoral Thesis. Switzerland: University of Bern, 1983.

      8. Weissenberger BFJ. Die Stellschraube im Rahmen der Behandlung von Malleolarfrakturen. Doctoral Thesis. Switzerland: University of Zürich, 1989.

      9. Müller ME, Allgöwer M, Willenegger H. Manual of internal fixation. Berlin: Springer, 1970.

      10. Henkemeyer H, Püschel R, Burri C. Experimentelle Untersuchungen zur Biomechanik der Syndesmose. Langenbecks Arch Chir, Suppl, Forum 1975. p. 369.

        • De Souza L.J.
        • Gustilo R.B.
        • Meyer T.J.
        Results of operative treatment of displaced external rotation-abduction fractures of the ankle.
        J. Bone Jt. Surg. 1985; 67A: 1066-1073
        • Leeds H.C.
        • Ehrlich M.G.
        Instability of the distal tibiofibular syndesmosis after bimalleolar and trimalleolar ankle fractures.
        J. Bone Jt. Surg. 1984; 66A: 490-503
        • Wilson Jr., F.C.
        • Skilbred L.A.
        Long-term results in the treatment of displaced bimalleolar fractures.
        J. Bone Jt. Surg. 1966; 48A: 1065-1078
        • Heim U.F.A.
        Trimalleolar fractures: late results after fixation of the posterior fragment.
        Orthopedics. 1989; 12: 1053-1059
        • Lauge-Hansen N.
        Fractures of the ankle. Part IV. Clinical use of genetic roentgen diagnosis and genetic reduction.
        Arch. Surg. 1952; 64: 488-500