Levator Ani Muscle Avulsion: Risks, Symptoms, and the Need for Better Training Tools

Author: Rebecca Wytsma, B.Eng.
Reviewed by Melissa Davidson, Ph.D.
January 4, 2026

Levator Ani Muscle (LAM) avulsion is a condition that significantly impacts pelvic support, birth recovery, and long-term pelvic health. However, due to its subtle presentation, many practitioners find LAM avulsion challenging to diagnose, which can result in delayed treatment for patients. Clinical tools that train healthcare practitioners in avulsion detection have the potential to improve diagnostic accuracy and patient outcomes.

What Is LAM Avulsion?

The levator ani is a key muscle group of the pelvic floor, providing support to the pelvic organs and helping maintain continence. The muscle group originates from the pubic bone and inserts into the coccyx, and includes the puborectalis, pubococcygeus, and iliococcygeus [1].

LAM avulsion occurs when part of the muscle group detaches from the pubic bone. This injury generally occurs during childbirth due to the extreme stretching that the pelvic muscles undergo during vaginal delivery [2]. LAM avulsion is an unfortunately common condition, occurring in 1/3 of women with vaginal deliveries [3]. Risk of avulsion increases with the use of forceps for delivery, the length of the second stage of labour, fetal head circumference, and maternal age [3].

Avulsion is important to diagnose, as it can contribute to pelvic organ prolapse (POP) [4]. When the LAM detaches from the pubic bone, the levator hiatus increases in area, creating more space for the pelvic organs to sink down into [5]. LAM avulsion can contribute to more significant POP and result in increased recurrence of POP even after surgical correction [6].

Treatment

Practitioners have not yet found a way to successfully reattach the LAM with surgery, therefore treatment of LAM avulsion aims to optimize remaining pelvic floor function and support. Interventions include [1]:

  • Pelvic floor physiotherapy: To strengthen intact musculature and provide symptom management.
  • Treatment with pessaries: To manage prolapse symptoms.
  • Surgical treatment of any prolapse: For significant prolapse, surgical repair may be considered, though outcomes can differ in patients with avulsion [6].

Diagnosis of LAM Avulsion

There are two primary methods that healthcare practitioners can use to assess LAM avulsion: 1) digital palpation (palpation of the vaginal canal for the absence of muscle bulk and measurement of width between LAM insertion sites), and 2) imaging (3D transperineal ultrasound or MRI). Several studies have investigated the reliability of these two methods.

Though imaging techniques are effective and reliable at diagnosing LAM avulsion [7] [8], palpation is the most common and affordable clinical practice. However, diagnosis of LAM avulsion by palpation is difficult, and substantial training is required for practitioners to be able to make accurate diagnoses [9] [8]. Since the presentation of LAM avulsion is subtle, its symptoms overlap with general pelvic floor dysfunction, and postpartum tissue changes can complicate assessment, this skill can be challenging even for experienced practitioners. The reliability and reproducibility of this diagnostic method depend on the experience of the practitioner [10].

Why Better Training Tools Are Essential for Detecting LAM Avulsion

The pelvic floor is an area of the body not often represented by simulation training tools. As a result, it is common for healthcare students to learn through didactic lessons and sometimes even peer-to-peer training. Though beneficial for experiential learning, peer-to-peer practice is not always a well-accepted learning mode for students [11] [12], and students may not be trained on specific conditions, such as POP, if these are not represented in their peers [13].  Realistic simulation training tools have the potential to enable all healthcare practitioners to improve clinical skills and enhance learning. In particular, a simulation tool for training practitioners to detect LAM avulsion from palpation can have the following impact:

1. Improved Diagnostic Accuracy

An anatomically accurate training tool can allow practitioners to learn what an avulsed LAM feels like during palpation, how to correctly locate the pubic bone and muscle origins, and how to distinguish intact versus avulsed muscle attachments. This hands-on practice can lead to increased diagnostic accuracy and fewer misdiagnoses.

2. Earlier Detection and Better Patient Outcomes

When clinicians can confidently detect avulsion, they can improve patient care by:

  • Providing earlier education and support for patients
  • Referring patients for imaging when appropriate
  • Tailoring postpartum rehabilitation strategies
  • Discussing long-term expectations for pelvic health with patients

3. Enhanced Patient Education

Models that visually and physically represent pelvic anatomy help patients better understand their diagnosis and treatment options. This builds trust and encourages informed decision-making.

Conclusion

LAM avulsion is a maternal birth injury with significant implications for long-term pelvic health. Recognition of this injury within the first 6–12 months post-partum and tailored treatment can improve patients’ quality of life and long-term health outcomes. High-quality, anatomically accurate training tools can help practitioners master palpation techniques and confidently detect avulsion.

Granville Biomedical developed the Lily – Levator Ani Muscle Model as a tool to demonstrate pessary placement and to allow practitioners to rehearse palpation techniques for diagnosing levator ani muscle avulsion. The Lily model features a levator ani muscle that can be removed to simulate unilateral and bilateral avulsion, along with a rigid coccyx.

 

References

[1] Yang, J. M. and Huang, W.C. (2025). Update on Diagnosis and Treatment for Levator Avulsion. J Med Ultrasound, 33(2), pp. 108-111.
[2] Dietz, H.P. (2013). Pelvic floor trauma in childbirth. Aust N Z J Obstet Gynaecol, 53(3), pp. 220-230.
[3] Dietz, H.P. (2012). Clinical consequences of levator trauma. Ultrasound Obstet Gynecol, 39(4), pp. 367-371.
[4] Dietz, H.P. and Simpson, J. M. (2008). Levator trauma is associated with pelvic organ prolapse. Int. J. Obstet. Gyanecol., 115(8), pp. 979-984.
[5] Croft, S. Levator Avulsion: Simply Explained. Association for Pelvic Organ Prolapse Support. Available: https://www.pelvicorganprolapsesupport.org/levator-avulsion-simply-explained
[6] Dietz, H.P., Chantarasorn, V., and Shek, K. L. (2010). Levator avulsion is a risk factor cystocele recurrence.Ultrasound Obstet Gynecol, 36(1), pp. 76-80.
[7] Kearney, R., Miller, J. M., and DeLancey, J. O. L. (2009) Interrater Reliability and Physical Examination of the Pubovisceral Portion of the Levator Ani Muscle, Validity Comparisons using MR Imaging. Neurourol Urodyn, 25(1), pp. 50-54.
[8] Dietz, H.P., Hyland G., and Hay-Smith, J. (2006). The assessment of levator trauma: a comparison between palpation and 4D pelvic floor ultrasound. Neurourol Urodyn, 25(5), pp. 424-427.
[9] Atan, I. K., et al. (2022). Levator ani muscle avulsion: Digital palpation versus tomographic ultrasound imaging. Int J Gynaecol Obstet, 156(2), pp. 270-275.
[10] Dietz, H.P., Moegni, F., and Shek, K. L. (2012). Diagnosis of levator avulsion injury: a comparison of three methods. Ultrasound Obstet Gynecol, 40(6), pp. 693-698.
[11] Sherburn, M., Virtue, D., and Remedios, L. (2018). Exploring graduate physiotherapy students' experience of intimate peer physical examinations. Philadelphia.
[12] Delany, C. and Frawley, H. (2012). A process of informed consent for student learning through peer physical examination in pelvic floor physiotherapy practice. Physiotherapy, 98(1), pp. 33-39.
[13] Zekaria, Y. et al. (2025), Requirements and Value Elicitation for a High-Fidelity Pelvic Floor Simulator for Physiotherapists: Mixed Methods Study. JMIR Human Factors, 12(72119).

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