Skip to main content

Biomechanics of the interlocking nail

A study of the proximal interlock


Conventional interlocking nails for the femur use an inclined proximal interlocking screw; the AO/ASIF universal interlocking nail utilizes a transverse interlocking screw which is anchored in cortical bone. The transverse position of the screw allows one to employ the nail for either the right or left side. The yield strength of the thinner diameter transverse screw, (thread 4.5 mm, core 3.0 mm) was compared with that of the Grosse-Kempf nail oblique screw (thread 6.3 mm, core 4.5 mm) by testing in cadaver femora to evaluate the risk of fatigue failure. The test, performed using slow loading rates (50 N/s), simulated either a diaphyseal or a subtrochanteric fracture situation. The test rig applied a load corresponding to body weight and pull at the trochanter. Taking the highest load without plastic deformation as a criterion, the mechanical strength of the two screws was evaluated for each fracture situation. The thinner but shorter transverse interlocking screw demonstrated higher strength450O N vs. 3000 N; P ≤ 0.02) than the thicker inclined screw in the diaphyseal and the subtrochanteric fracture situation (2300 N vs. 1100 N; P ≤ 0.06). The biomechanical test showed the transverse screw to have sufficient and superior strength.

This is a preview of subscription content, access via your institution.


  1. 1.

    Beaupré GS, Schneider E, Perren SM (1984) Stress analysis of a partially slotted intramedullary nail. J Orthop Res 2:369–376

    Google Scholar 

  2. 2.

    Bonnel F, Karger C (1984) Enclouage centro-médullaire avec verrouillage: performances mécaniques du material de Strasbourg. In: Kempf I (ed) Dix ans d'enclouage centro-médullaire avec verrouillage. Laporte, Strasbourg

    Google Scholar 

  3. 3.

    Bonnel F, Karger J, Peruchon E, Micallef JP (1984) Biomechanical behavior of the bolted nail. In: Kempf I (ed) Dix ans d'enclouage centro-médullaire avec vérrouillage. Laporte, Strasbourg

    Google Scholar 

  4. 4.

    Börner M, Mattheck C, Häberer B (1985) Biomechanische Analyse eines seltenen Metallbruches an einem Verriegelungsnagel. Unfallchirurg 88:235–238

    Google Scholar 

  5. 5.

    Börner M, Mattheck C (1985) Ein neues Nagelprofil für die Verriegelungsnägel mit hoher Ermüdungsfestigkeit. Unfallchirurg 88:263–266

    Google Scholar 

  6. 6.

    Börner M, Mattheck C, Berndt J (1987) Ein Verriegelungsnagel mit verbesserter Ermüdungsfestigkeit. Biomed Tech 32:305–308

    Google Scholar 

  7. 7.

    Börner M (1988) Finite-element Analyse eines neuen Verriegelungsnagels. Hefte Unfallheilkd 200:84

    Google Scholar 

  8. 8.

    Brien W, Wiss DA, Peter K, Merrit PO (1987) Subtrochanteric fractures of the femur: treatment with locked medullary nails. Paper no. 185, 54th American Academy of Orthopaedic Surgeons, 22–27 Jan 1987

  9. 9.

    Browner B (1986) Pitfalls, errors, and complications in the use of locking Kiintscher nails. Clin Orthop 212:192–208

    Google Scholar 

  10. 10.

    Browner BD, Cole JD (1987) Current status of locked intramedullary nailing: a review. J Orthop Trauma 1:183–195

    Google Scholar 

  11. 11.

    Brumback RJ, Handal JA, Poka A, Burgess AR, Feddis G (1987) Radiographic analysis of the Brooker-Wills interlocking nail in the treatment of comminuted femoral fractures. J Orthop Trauma 1:120–129

    Google Scholar 

  12. 12.

    Bucholz RW, Ross SE, Lawrence KL (1987) Fatigue fracture of the interlocking nail in the treatment of fractures of the distal part of the femoral shaft. J Bone Joint Surg [Am] 69: 1391–1399

    Google Scholar 

  13. 13.

    Burri C, Lob G (1982) Die Plattenosteosynthese am Femurschaft. Hefte Unfallheilkd 158:117–122

    Google Scholar 

  14. 14.

    Garbarino JL, Brumback RJ, Poka A, Burgess AR (1987) Closed interlocking intramedullary nailing of subtrochanteric fractures. Paper no. 187, 54th American Academy of Orthopaedic Surgeons, 22–27 Jan 1987

  15. 15.

    Haas N, Krettek C, Gotzen L (1985) Biomechanical properties and first clinical results of a newly designed intramedullary fixation device. In: Perren SM, Schneider E (eds) Biomechanics: current interdisciplinary research. Nijhoff, Dordrecht, pp 471–474

    Google Scholar 

  16. 16.

    Hanks GA, Foster WC, Cardea JA (1988) Treatment of femoral shaft fractures with the brooker wills interlocking intramedullary nail. Clin Orthop 226:206–218

    Google Scholar 

  17. 17.

    Heitemeyer M, Kemper F, Hierholzer G, Haines J (1987) Severely comminuted femoral shaft fractures: treatment by bridging-plate osteosynthesis. Arch Orthop Trauma Surg 106:327–330

    Google Scholar 

  18. 18.

    Herzog K (1958) Die Technik der geschlossenen Marknagelung frischer Tibiafrakturen mit dem Rohrschlitznagel. Chirurg 29:501–506

    Google Scholar 

  19. 19.

    Johnson KD, Tencer AF, Blumenthal S, August A, Johnston DWC (1986) Biomechanical performance of locked intramedullary nail system in comminuted femoral shaft fractures. Clin Orthop 206:151

    Google Scholar 

  20. 20.

    Johnson KD, Greenberg M (1987) Comminuted femoral shaft fractures. Orthop Clin North Am 18:133–147

    Google Scholar 

  21. 21.

    Kempf I, Grosse A, Lafforgue D (1978) L'apport du verrouillage dans l'enclouage centro-médullaire des os longs. Rev Chir Orthop 64:635–651

    Google Scholar 

  22. 22.

    Kempf I, Jaeger JH, Clavert JM, Mochel D, Glaesener R (1978) L'enclouage centro-m6dullaire avec alésage. Rev Chir Orthop 64:629–634

    Google Scholar 

  23. 23.

    Kempf I, Grosse A, Beck G (1985) Closed locked intramedullary nailing. J Bone Joint Surg [Am] 67A:709–719

    Google Scholar 

  24. 24.

    Kempf I, Karger C, Willinger R, Francois JM, Cornet A, Renault D, Bonnel F (1985) Locked intramedullary nailing — improvement of mechanical properties. In: Perren SM, Schneider E (eds) Biomechanics: current interdisciplinary research. Nijhoff, Dordrecht

    Google Scholar 

  25. 25.

    Kinast C, Bolhofner B, Mast J, Ganz R (1989) Subtrochanteric fractures of the femur — results of treatment with the 95° condylar blade plate. Clin Orthop 238:122–130

    Google Scholar 

  26. 26.

    Klemm K, Schellmann WD (1972) Dynamische und statische Verriegelung des Marknagels. Monatsschr Unfallheilkd 75:568–575

    Google Scholar 

  27. 27.

    Klemm K, Schellmann WD (1976) Die Verriegelungsnagelung. Aktuel Traumatol 6:377–380

    Google Scholar 

  28. 28.

    Klemm K, Börner M (1985) Interlocking nailing: extended scope of application for Küntscher nails. Med Focus 6:10–13

    Google Scholar 

  29. 29.

    Klemm KW, Börner M (1986) Interlocking nails of complex/ fractures of the femur and tibia. Clin Orthop 212:89–100

    Google Scholar 

  30. 30.

    Küntscher G (1968) Die Marknagelung des Trümmerbruches. Langenbecks Arch Klin Chir 322:1063

    Google Scholar 

  31. 31.

    Legal H (1984) Einführung in die Biomechanik des Htiftgelenkes. In: Tönnis D (eds) Die angeborene Hüftdysplasie und Hüftluxation. Springer, Berlin Heidelberg New York

    Google Scholar 

  32. 32.

    Levin PE, Schoen RW, Browner BD (1987) Radiation exposure to the surgeon during closed interlocking intramedullary nailing. J Bone Joint Surg [Am] 69A:761–766

    Google Scholar 

  33. 33.

    Loomer R, Meek R, DeSommer F (1980) Plating of femoral shaft fractures: the Vancouver experience. J Trauma 30:1038–1042

    Google Scholar 

  34. 34.

    Maatz R (1983) Zur Infektionshäufigkeit nach gedeckter oder offener Nagelung geschlossener Frakturen. Aktuel Traumatol 13:175–178

    Google Scholar 

  35. 35.

    Modny MT, Bambara J (1953) The perforated cruciate intramedullary nail: preliminary report of its use in geriatric patients. J Am Geriatr Soc 579–588

  36. 36.

    Müller ME, Allgöwer M, Schneider R, Willenegger H (1979) Manual of internal fixation. Springer, Berlin Heidelberg New York

    Google Scholar 

  37. 37.

    Oertli D, Matter P, Scharplatz D, Zehnder R (1984) Evaluation of surgically treated fractures: analysis of the Swiss AO/ASIF Documentation 1967–1980. AO Bulletin 6

  38. 38.

    Pahud B, Vasey H (1987) Delayed internal fixation of femoral shaft fractures - is there an advantage? J Bone Joint Surg [Br] 69:391–394

    Google Scholar 

  39. 39.

    Perren SM (1987) Biomechanics of intramedullary nailing. In: Browner BB, Edwards CC (eds) The science and practice of intramedullary nailing. Lea and Febiger, Philadelphia

    Google Scholar 

  40. 40.

    Renault D, Willinger R (1984) Amélioration des performances du clou point de vue d'un ingenieur. In: Kempf I (ed) Dix ans d'enclouage centro-médullaire avec verrouillage. Laporte, Strasbourg

    Google Scholar 

  41. 41.

    Ritter G, Grünert A, Weigand H (1982) Experimentelle Untersuchungen über die axiale Druckbelastbarkeit von Röhrenknochen durch Steinmann-Nägel. Aktuel Traumatol 2:96–102

    Google Scholar 

  42. 42.

    Rüedi T, Lüscher JN (1979) Results after internal fixation of comminuted fractures of the femoral shaft with DC plates. Clin Orthop 138:74–76

    Google Scholar 

  43. 43.

    Anon (1987) Russell-Taylor reconstruction nail: surgical technique. Richards Medical Co, Memphis

  44. 44.

    Tarr RR, Wiss DA (1986) The mechanics and biology of intramedullary fracture fixation. Clin Orthop 212:10–17

    Google Scholar 

  45. 45.

    Taylor JC (1987) Clinical results of 100 femoral shaft fractures treated with the Russel Taylor interlocking nail system. Orthop Trans JBJS 11:491

    Google Scholar 

  46. 46.

    Tencer AF, Johnson KD, Johnston DWC, Gill K (1984) A biomechanical comparison of various methods of stabilization of subtrochanteric fractures of the femur. J Orthop Res 2:297–305

    Google Scholar 

  47. 47.

    Thoresen BO, Antti A, Ekeland A, Stomsoe K, Fooeras G, Haukebo A (1985) Interlocking intramedullary nailing in femoral shaft fractures. J Bone Joint Surg [Am] 64:1313–1319

    Google Scholar 

  48. 48.

    Tscherne H, Trentz O (1977) Operationstechnik und Ergebnisse bei Mehrfragmenttrümmerbrüchen des Femurschaftes. Unfallheilkunde 80:221–230

    Google Scholar 

  49. 49.

    Tscherne H, Haas N, Krettek C (1986) Intramedullary nailing combined with cerclage wiring in the treatment of fractures of the femoral shaft. Clin Orthop 212:62–67

    Google Scholar 

  50. 50.

    White GM, Healy WL, Brumback RJ, Burgess AR, Brooker AF (1986) The treatment of fractures of the femoral shaft with the Brooker-Wills distal locking intramedullary nail. J Bone Joint Surg [Am] 68:865–876

    Google Scholar 

  51. 51.

    Winquist RA, Hansen ST (1980) Comminuted fractures of the femoral shaft treated by intramedullary nailing. Orthop Clin North Am 2:633–648

    Google Scholar 

  52. 52.

    Winquist RA, Hansen ST, Clawson DK (1984) Closed intramedullary nailing of femoral fractures. A report of 520 cases. J Bone Joint Surg [Am] 66:529–539

    Google Scholar 

  53. 53.

    Wiss DA, Flemming CH, Matta JM, Clark D (1986) Comminuted and rotationally unstable fractures of the femur treated with an interlocking nail. Clin Orthop 212:35–47

    Google Scholar 

  54. 54.

    Wruhs O (1986) Vergleichende Stabilitdtsuntersuchungen nach Nagelung von Frakturen des Oberschenkelschaftes — Eine experimentelle Studie am Leichenknochen. Klin Wochenschr [Suppl] 169:3–16

    Google Scholar 

  55. 55.

    Vecsei V, Mockwitz J, Börner M, Wruhs W (1983) Mißerfolge nach Verriegelungsnagelung — Fehlerhafte Technik und Komplikationen. Hefte Unfallheilkd 161:143–153

    Google Scholar 

  56. 56.

    Vecsei V (1980) Der Bübelbolzen — eine Ergänzung zur Verriegelungsnagelung. Unfallchirurgie 6:193–198

    Google Scholar 

  57. 57.

    Zuber K, Schneider E, Eulenberger J, Perren SM (1988) Form und Dimension der Markhöhle menschlicher Femora im Hinblick auf die Passung von Marknagelimplantaten. Unfallchirurg 91:314–319

    Google Scholar 

  58. 58.

    Zuckerman JD, Veith RG, Johnson KD, Bach AW, Hansen ST, Solvik ST (1987) Treatment of unstable femoral shaft fractures with closed interlocking intramedullary nailing. J Orthop Trauma 1:209–218

    Google Scholar 

  59. 59.

    Zych GA, Greenbarg RE, Milne EL, Levi DM, Latta LL, Weiss C (1988) Mechanics of distal locking IM nail fixation in osteoporotic and normal femora. Transactions of 34th Annual Meeting of the Orthopedic Research Society, 1–4 Feb 1988, Atlanta, Georgia

Download references

Author information



Corresponding author

Correspondence to C. Kinast.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Kinast, C., Frigg, R. & Perren, S.M. Biomechanics of the interlocking nail. Arch Orthop Trauma Surg 109, 197–204 (1990).

Download citation


  • Fatigue
  • Plastic Deformation
  • Yield Strength
  • Cortical Bone
  • Fatigue Failure