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Vet Comp Orthop Traumatol 1992; 05(02): 71-75
DOI: 10.1055/s-0038-1633070
Original Research
Schattauer GmbH

Intramedullary Nailing of Experimental Femoral Midshaft Osteotomies in Cats with Biodegradable Rods of Polylactic Acid

J. E. Räihä
1   department of Clinical Sciences, College of Veterinary Medicine, Helsinki, University of Technology, Tampere, Finland
,
M. Mero
1   department of Clinical Sciences, College of Veterinary Medicine, Helsinki, University of Technology, Tampere, Finland
,
M. Morelius
1   department of Clinical Sciences, College of Veterinary Medicine, Helsinki, University of Technology, Tampere, Finland
,
P. Rokkanen
2   Department of Orthopaedics and Traumatology, Helsinki University Central Hospital, Helsinki, University of Technology, Tampere, Finland
,
P. Törmälä
3   Biomaterials Laboratory, University of Technology, Tampere, Finland
› Author Affiliations
Further Information

Publication History

Received for publication: 16 July 1991

Publication Date:
06 February 2018 (online)

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Summary

Fracture repair by intramedullary support with one or several steel implants is a cheap and quick technique, especially suitable for simple femoral, tibial and humeral fractures in small animals. These implants, however, usually have to be removed due to their excessive rigidity causing migration or osteoporosis. The biodegradable implants of polylactic and polyglycolic acid available for fracture re-pair are usually too short to be used in the medullary canals of dogs and cats. A new extrusion technique has provided essentially unlimited length rods of left isomeric polylactic acid with strength values comparable to steel, but a stiffness modulus; close to bone.

To test their use for intramedullary nailing such rods of diameter 1.1 and 2 mm were used to stack pin femoral osteotomies in four cats. Follow-up time was 24 weeks. All femurs healed, but with slight or moderate angulation or rotation and fair callus formation. Two had a bone loss defect at the lateral osteotomy line. Histology revealed minor foreign body reactions from the implants.

This technique is being developed to involve only one implant with ability to prevent rotation and a stiffness of about 40 to 60 gigapascals (between bone and steel) to provide adequate initial stiffness before biodegrading.

A new extrusion technique has enabled manufacturing of longer rods of totally biodegradable polylactic acid. These were tested for intramedullary use with a stack pinning technique in four cat femurs. All osteotomies healed with fair callus formation and slight or moderate deviations or rotations. Two femurs had a bone loss defect at the lateral osteotomy line. Histology revealed good tolerance to the foreign material.

Keywords

Intramedullary stack pinning - biodegradable implants - left isomeric polylactic acid
 

  • REFERENCES

  • 1 Küntscher G. Die Behandlung von Knochenbriichen bei Tieren durch Mark-nagelung. Archiv für Wissenschaft und praktische Tierheilkunde 1940; 75: 262-73.
    PubMedGoogle Scholar
  • 2 Frick EJ, Witter RE, Mosier JE. Treatment of fractures by intramedullary pinning. North Am Vet 1948; 29: 95-7.
    PubMedGoogle Scholar
  • 3 Brown SA, Mayor MB. Intramedullary nailing with metals and plastics. In: Current concepts of internal fixation of fractures. Uhthoff HK. (ed). Berlin: Springer; 1980: 423-8.
    Google Scholar
  • 4 Meade JB, Cowin SC, Klawitter JJ, Van Buskirk WC, Skinner HB. Bone remodeling due to continuously applied loads. Calcif Tissue Int 1984; 36: 25-30.
    CrossrefPubMedGoogle Scholar
  • 5 Pead MJ, Skerry TM, Lanyon LE. Direct transformation from quiescence to bone formation in the adult periosteum following a single brief period of bone loading. J Bone Miner Res 1988; 6: 647-56.
    PubMedGoogle Scholar
  • 6 Cook SD, Weinstein AM, Luedemann R, Lavernia C, Skinner HB, Klawitter JJ. The effects of intramedullary implants on bone strains and remodeling in the femur. Biomater Med Dev Artif Organs 1982; 10: 21-40.
    PubMedGoogle Scholar
  • 7 Luedemann R, Thomas KA, Cook SD. Bone remodeling associated with a flexible femoral intramedullary implant. Biomater Med Dev Artif Organs 1986; 14: 181-94.
    PubMedGoogle Scholar
  • 8 Uhthoff HK, Dubuc FL. Bone structure changes in the dog under rigid internal fixation. Clin Orthop 1971; 81: 165-70.
    CrossrefPubMedGoogle Scholar
  • 9 Claes L. The mechanical and morphological properties of bone beneath internal fixation plates of differing rigidity. J Orthop Res 1989; 7: 170-7.
    CrossrefPubMedGoogle Scholar
  • 10 Tonino AJ, Davidson CL, Klopper PJ, Linclau LA. Protection from stress in bone and its effect. J Bone Joint Surg 1976; 58-B: 107-13.
    CrossrefPubMedGoogle Scholar
  • 11 Törmälä P, Rokkanen P, Laiho J, Tamminmäki M, Vainionpää S. Material for osteosynthesis devices. US patent no. 4743257, 1988
    PubMedGoogle Scholar
  • 12 Axelson P, Räihä J, Mero M, Vainionpää S, Törmälä P, Rokkanen P. The use of a biodegradable implant in fracture fixation: a review of the literature and a report of two clinical cases. J Small Anim Pract 1988; 29: 249-55.
    CrossrefPubMedGoogle Scholar
  • 13 Axelson P, Räihä J, Sittnikow K, Skutnabb K, Mero M, Vainionpää S, Törmälä P, Rokkanen P. The use of biodegradable implants in the fixation of small animal cancellous bone fractures. Acta Vet Scand 1988; 29: 469-76.
    PubMedGoogle Scholar
  • 14 Axelson P, Mäkelä A, Vainionpää S, Mero M, Rokkanen P. Biodegradable implants in the fixation of physeal fractures in cats and dogs. Acta Vet Scand 1988; 29: 477-84.
    PubMedGoogle Scholar
  • 15 Rokkanen P, Böstman O, Vainionpää S, Vihtonen K, Törmälä P, Laiho J, Kilpikari J, Tamminmäki M. Biodegradable implants in fractures of the ankle. Lancet 1985; 22-1: 1422-4.
    PubMedGoogle Scholar
  • 16 Böstman O, Mäkelä EA, Törmälä P, Rok-kanen P. Transphyseal fracture fixation using biodegradable pins. J Bone Joint Surg 1989; 71-B: 706-7.
    CrossrefPubMedGoogle Scholar
  • 17 Böstman O, Hirvensalo E, Vainionpää S. et al. Ankle fractures treated using biodegradable internal fixation. Clin Orthop 1989; 238: 195-203.
    CrossrefPubMedGoogle Scholar
  • 18 Hirvensalo E, Böstman O, Vainionpää S, Törmälä P, Rokkanen P. Biodegradable fixation in intra-articular fractures of the elbow joint. Acta Orthop Scand 1988; 59(5): 78.
    PubMedGoogle Scholar
  • 19 Räihä JE, Axelson PB. Experience from two years of treating clinical small animal fractures with totally biodegradable polylactic acid rods. European Society of Veterinary Orthopaedics and Traumatology, 4th Annual Meeting, 8- 9 June 1990 Uppsala, Sweden.:
    PubMedGoogle Scholar
  • 20 Törmälä P, Rokkanen P, Vainionpää S, Laiho J, Heponen V-P. Surgical materials and devices. US patent no. 4968317, 1990
    PubMedGoogle Scholar
  • 21 Klopper PJ, Tonino AJ. Internal fixation of femur fractures with plastic rods - an experimental study. In: Current concepts of internal fixation of fractures. Uhthoff HK. (ed). Berlin: Springer; 1980: 416-2.
    Google Scholar
  • 22 Church EM, Scrader SC. Use of flexible intramedullary rods for fixation of femoral fractures in eight dogs. JAVMA 1990; 1: 71-6.
    PubMedGoogle Scholar
  • 23 Räihä JE, Parchman M, Krook L, Vainionpää S, Mero M, Rokkanen P, Törmälä P. Fixation of trochanteric osteotomies in laboratory beagles with absorbable screws of polylactic acid. Vet Comp Orthop Trauma 1990; 3: 123-9.
    PubMedGoogle Scholar
  • 24 Partio EK, Böstman O, Vainionpää S, Pätiälä H, Hirvensalo E, Vihtonen K, Törmälä P, Rokkanen P. The treatment of cancellous bone fractures with biodegradable screws. Acta Orthop Scand 1988; 59 (Suppl.): 227.
    PubMedGoogle Scholar