Skip to main content
Log in

Rotator cuff changes in a full thickness tear rat model: verification of the optimal time interval until reconstruction for comparison to the healing process of chronic lesions in humans

  • Basic Science
  • Published:
Archives of Orthopaedic and Trauma Surgery Aims and scope Submit manuscript

Abstract

Background

The aim of the study was to develop a standardized rat model for chronic rotator cuff tears. Therefore, a time point of degenerative changes that shows comparable histological changes to the chronic tendon tears in humans had to be determined. The rat shoulder has already been described as a standardized model for investigation of the healing behavior in acute supraspinatus lesions. Little data exist about the possibility of generating a chronic rotator cuff lesion.

Methods

We performed a complete detachment of the supraspinatus tendon in 45 Sprague-Dawley rats. After an interval of 3, 6 and 9 weeks (15 rats in each group), the macroscopic and histological changes were analyzed. The histological investigation included atrophy and fatty muscle degeneration, tendon degeneration and the grade of inflammatory changes. For evaluation of tendon degeneration, a modified MOVIN-Score was used. The contralateral shoulder provided as control group.

Results

Macroscopically the defect showed an increasing coverage with scar tissue over time with a complete closure in 73% after 9 weeks. The 3 week group showed the highest rate of persisting defects (80%). The atrophy of the supraspinatus muscle decreased from initial slight atrophy to a nearly normal muscle status in the 9 week group. Fatty infiltration was found in three animals per group regardless of the time interval after detachment. Tendon degeneration (modified MOVIN-Score) showed no significant difference between 3 and 6 weeks (p = 0.93) whereas after 9 weeks a significant increased degeneration was found (p < 0.01). In the early phase (3 and 6 weeks), inflammatory cells could be detected more frequently.

Conclusions

The results show that a chronic tear of the human rotator cuff can be imitated in the rat model with some exclusion. The rapid self-healing response in the rat and the fatty infiltration of the human muscle are the main differences. However, tendon degeneration, inflammation and muscle atrophy combined with a persisting defect at 3 weeks after detachment are comparable to the chronic tendon tears in humans. This model can serve as a basis for further research in the field of rotator cuff repair for chronic lesions.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others

References

  1. Fuchs S, Chylarecki C, Langenbrinck A (1999) Incidence and symptoms of clinically manifest rotator cuff lesions. Int J Sports Med 20:201–205

    Article  CAS  PubMed  Google Scholar 

  2. Boszotta H, Prünner K (2004) Arthroscopically assisted rotator cuff repair. Arthroscopy 20:620–626

    Article  PubMed  Google Scholar 

  3. Liem D, Lichtenberg S, Magosch P, Habermeyer P (2007) Magnetic resonance imaging of arthroscopic supraspinatus tendon repair. J Bone Joint Surg Am 89:1770–1776

    Article  PubMed  Google Scholar 

  4. Zumstein MA, Jost B, Hempel J, Hodler J, Gerber C (2008) The clinical and structural long-term results of open repair of massive tears of the rotator cuff. J Bone Joint Surg Am 90:2423–2431

    Article  PubMed  Google Scholar 

  5. Harryman DT 2nd, Mack LA, Wang KY, Jackins SE, Richardson ML, Matsen FA 3rd (1991) Repairs of the rotator cuff. Correlation of functional results with integrity of the cuff. J Bone Joint Surg Am 73:982–989

    PubMed  Google Scholar 

  6. Iannotti JP (1994) Full-thickness rotator cuff tears: factors affecting surgical outcome. J Am Acad Orthop Surg 2:87–95

    PubMed  Google Scholar 

  7. Romeo AA, Hang DW, Bach BR Jr, Shott S (1999) Repair of full thickness rotator cuff tears. Gender, age, and other factors affecting outcome. Clin Orthop Relat Res 367:243–255

    Article  PubMed  Google Scholar 

  8. Galatz LM, Rothermich SY, Zaegel M, Silva MJ, Havlioglu N, Thomopoulos S (2005) Delayed repair of tendon to bone injuries leads to decreased biomechanical properties and bone loss. J Orthop Res 23:1441–1447

    CAS  PubMed  Google Scholar 

  9. Thomopoulos S, Williams GR, Soslowsky LJ (2003) Tendon to bone healing: differences in biomechanical, structural, and compositional properties due to a range of activity levels. J Biomech Eng 125:106–113

    Article  CAS  PubMed  Google Scholar 

  10. Aspenberg P, Forslund C (1999) Enhanced tendon healing with GDF 5 and 6. Acta Orthopaedica 70:51–54

    Article  CAS  Google Scholar 

  11. Kovacevic D, Rodeo SA (2008) Biological augmentation of rotator cuff tendon repair. Clin Orthop Relat Res 466:622–633

    Article  PubMed  Google Scholar 

  12. Molloy T, Wang Y, Murrell G (2003) The roles of growth factors in tendon and ligament healing. Sports Med 33:381–394

    Article  PubMed  Google Scholar 

  13. Soslowsky LJ, Carpenter JE, DeBano CM, Banerji I, Moalli MR (1996) Development and use of an animal model for investigations on rotator cuff disease. J Shoulder Elbow Surg 5:383–392

    Article  CAS  PubMed  Google Scholar 

  14. Maffulli N, Longo UG, Franceschi F, Rabitti C, Denaro V (2008) Movin and Bonar Score assess the same characteristics of tendon histology. Clin Orthop Relat Res 466:161–1605

    Article  Google Scholar 

  15. Movin T, Gad A, Reinholt F, Rolf C (1997) Tendon pathology in long-standing achollodynia. Biopsy findings in 40 patients. Acta Orthop Scand 68:170–175

    Article  CAS  PubMed  Google Scholar 

  16. Carpenter JE, Thomopoulos S, Flanagan CL, DeBano CM, Soslowsky LJ (1998) Rotator cuff defect healing: a biomechanical and histologic analysis in an animal model. J Shoulder Elbow Surg 7:599–605

    Article  CAS  PubMed  Google Scholar 

  17. Walch G, Levigne C (1997) Introduction to partial thickness tears of the supraspinatus tendon. In: Gazielly DF, Gleyze P, Thomas T (eds) The Cuff, 1st edn. Elsevier Masson, Amsterdam, pp 231–233

    Google Scholar 

  18. Yamaguchi K, Tetro AM, Blam O, Evanoff BA, Teefey SA, Middleton WD (2001) Natural history of asymptomatic rotator cuff tears: a longitudinal analysis of asymptomatic tears detected sonographically. J Shoulder Elbow Surg 10:199–203

    Article  CAS  PubMed  Google Scholar 

  19. Goutallier D, Postel JM, Lavau L, Bernageau J (1999) Impact of fatty degeneration of the supraspinatus and infraspinatus muscles on the prognosis of surgical repair of the rotator cuff. Rev Chir Orthop Réparatrice Appar Mot 85:668–676

    CAS  PubMed  Google Scholar 

  20. Barton ER, Gimbel JA, Williams GR, Soslowsky LJ (2005) Rat supraspinatus muscle atrophy after tendon detachment. J Orthop Res 23:259–265

    Article  PubMed  Google Scholar 

  21. Coleman SH, Fealy S, Ehteshami JR, MacGillivray JD, Altchek DW, Warren RF, Turner AS (2000) Chronic rotator cuff injury and repair model in sheep. J Bone Joint Surg Am 85:2391–2402

    Google Scholar 

  22. Fabiś J, Kordek P, Bogucki A, Synder M, Kolczynska H (1998) Function of the rabbit supraspinatus muscle after detachment of its tendon from the greater tubercle. Observations up to 6 months. Acta Orthop Scand 69:570–574

    Article  PubMed  Google Scholar 

  23. Thomazeau H, Rolland Y, Lucas C, Duval CM, Langlais F (1996) Atrophy of the supraspinatus belly. Assessment by MRI in 55 patients with rotator cuff pathology. Acta Orthop Scand 67:264–268

    Article  CAS  PubMed  Google Scholar 

  24. Hata Y, Saitoh S, Murakami N, Kobayashi H, Kaito T, Kato H (2005) Volume changes of supraspinatus and infraspinatus muscles after supraspinatus tendon repair: a magnetic resonance imaging study. J Shoulder Elbow Surg 14:631–635

    Article  PubMed  Google Scholar 

  25. Björkenheim JM (1989) Structure and function of the rabbit’s supraspinatusmuscle after resection of its tendon. Acta Orthop Scand 60:461–463

    Article  PubMed  Google Scholar 

  26. Schmutz S, Fuchs T, Regenfelder F, Steinmann P, Zumstein M, Fuchs B (2009) Expression of atrophy mRNA relates to tendon tear size in supraspinatus muscle. Clin Orthop Relat Res 467:457–464

    Article  PubMed  Google Scholar 

  27. Longo UG, Ruzzini L, Franceschi F, Rabitti C, Morini S, Maffulli N, Denaro V (2008) Histopathology of the supraspinatus tendon in rotator cuff tears. Am J Sports Med 36:533–538

    Article  PubMed  Google Scholar 

  28. Hashimoto T, Nobuhara K, Hamada T (2003) Pathologic evidence of degeneration as a primary cause of rotator cuff tear. Clin Orthop Relat Res 415:111–120

    Article  PubMed  Google Scholar 

  29. Yokota A, Gimbel JA, Williams GR, Soslowsky LJ (2005) Supraspinatus tendon composition remains altered long after tendon detachment. J Shoulder Elbow Surg 14:72S–78S

    Article  PubMed  Google Scholar 

  30. Gimbel JA, Van Kleunen JP, Mehta S, Perry SM, Williams GR, Soslowsky LJ (2004) Supraspinatus tendon organizational and mechanical properties in a chronic rotator cuff tear animal model. J Biomech 37:739–749

    Article  PubMed  Google Scholar 

  31. Benson RT, McDonnell SM, Rees JL, Athanasou NA, Carr AJ (2009) The morphological and immunocytochemical features of impingement syndrome and partial-thickness rotator-cuff tear in relation to outcome after subacromial decompression. J Bone Joint Surg Br 91:119–123

    CAS  PubMed  Google Scholar 

  32. Perry SM, McIlhenny SE, Hoffman MC, Soslowsky LJ (2005) Inflammatory and angiogenic mRNA levels are altered in a supraspinatus tendon overuse animal model. J Shoulder Elbow Surg 14:79S–83S

    Article  PubMed  Google Scholar 

Download references

Acknowledgments

The authors thank the “Deutsche Arthrose-Hilfe e.V.” for funding this study and our statistician Thomas Fabbro, PhD (Clinical Trial Unit, Basel) for his help.

Conflict of interest

None.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Andreas B. Imhoff.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Buchmann, S., Walz, L., Sandmann, G.H. et al. Rotator cuff changes in a full thickness tear rat model: verification of the optimal time interval until reconstruction for comparison to the healing process of chronic lesions in humans. Arch Orthop Trauma Surg 131, 429–435 (2011). https://doi.org/10.1007/s00402-010-1246-5

Download citation

  • Received:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00402-010-1246-5

Keywords

Navigation