Understanding Birth Injuries: Levator Ani Muscle Avulsion

In this article we will explore the clinical consequences of levator ani muscle avulsion, its risk factors, and current management strategies, including the role of pelvic floor physical therapy.

Levator ani muscle (LAM) avulsion is a significant concern in obstetric care, particularly for women undergoing vaginal delivery. This condition involves a tear in the levator ani muscle, which plays a crucial role in pelvic support and function. Avulsion of the levator ani muscle from its insertions has a significant impact on the function of the pelvic floor, often leading to symptoms such as pelvic organ prolapse, urinary and bowel incontinence, and sexual dysfunction.

The Clinical Consequences of Levator Ani Muscle Avulsion

According to Dietz (2012), levator ani avulsion can lead to a range of adverse outcomes, impacting a woman's quality of life. The levator ani muscle supports pelvic organs and maintains continence. When avulsion occurs, this support is compromised, increasing the risk of pelvic organ prolapse, urinary incontinence, and other functional disorders. The severity of these outcomes can vary, but they often necessitate further medical intervention.

In a study by Doxford-Hook (2023), the management of levator ani avulsion was systematically reviewed, highlighting the need for comprehensive strategies that consider both surgical and conservative options. Early identification and appropriate management are critical to mitigate long-term complications and improve patient outcomes.

Risk Factors for Levator Ani Muscle Avulsion

Understanding the risk factors for levator ani avulsion is essential for prevention. A study by González et al. (2017) found that obstetric anal sphincter injuries during vaginal delivery is a significant risk factor for avulsion. This connection emphasizes the importance of evidence based preventative techniques to reduce risk of obstetric anal sphincter injuries and perineal tears. 

Moreover, the epidemiological study by Fialkow (2008) indicated that the prevalence of surgically managed pelvic organ prolapse and urinary incontinence has increased over the years. This trend suggests that more women may be experiencing complications related to levator ani trauma, further highlighting the need for awareness and preventive measures during pregnancy and childbirth. 

What is the prevalence?

• Macroscopic trauma occurs in 10-30% of women (Dietz 2012)
• This increases to 62-66% with a forceps delivery (Gonzalez 2017)
• Microscopic trauma presents as hiatal ballooning or pelvic organ prolapse
• POP associated with LAM avulsion are more severe and have a tendency to recur even after surgical correction
• 10-20% of patients require surgical intervention in the future2

The Role of Pelvic Floor Physical Therapy in Levator Ani Avulsion Injuries

Pelvic floor physical therapy (PFPT) plays a vital role in the management of levator ani avulsion. This specialized therapy focuses on strengthening and rehabilitating the pelvic floor muscles, which can be weakened or damaged due to avulsion.

Benefits of Pelvic Floor Physical Therapy

1. Muscle Strengthening: Pelvic floor physical therapy can help restore strength and function to the levator ani and surrounding muscles.
2. Improved Functionality: Through pelvic floor strengthening and specific manual therapy, Pelvic floor physical therapy can help improve coordination and control of the pelvic floor, enhancing urinary and bowel function.
3. Pain Management: Many women experience pain following avulsion. Pelvic floor physical therapy can provide relief through manual therapy and relaxation techniques.
4. Prevention of Future Issues: Strengthening the pelvic floor can help prevent future complications, such as prolapse or incontinence, thus improving long-term outcomes.

Current Management Strategies for Levator Ani Avulsion Injuries

In conjunction with pelvic floor physical therapy, management of levator ani avulsion may also include surgical options for women with severe symptoms or significant avulsion. Procedures aimed at restoring pelvic support can be effective, but the decision must be made carefully, considering the patient’s risk factors and desire for future pregnancies.

Pelvic floor physical therapy stands out as a valuable tool in rehabilitation, enhancing recovery and improving quality of life for affected women. If you have more questions or would like to be evaluated for levator ani muscle avulsion, give our clinic a call to schedule an appointment today! 

References:

1. Dietz, H.P., 2012. Clinical consequences of levator trauma. Ultrasound Obstet. Gynecol. 39 (4), 367–371. [Internet]Apr 1 [cited 2020 Aug 9]Available from: https: //doi.wiley.com/10.1002/uog.11141.
2. Doxford-Hook EA, Slemeck E, Downey CL, Marsh FA. Management of levator ani avulsion: a systematic review and narrative synthesis. Archives of gynecology and obstetrics. 2023;308(5):1399-1408. doi:10.1007/s00404-023-06955-4
3. González MS, Garriga JC, Capel CD, Roda OP, Capó JP, Saladich IG. Is obstetric anal sphincter injury a risk factor for levator ani muscle avulsion in vaginal delivery? Ultrasound Obstet Gynecol. 2017;49(2):257–62.
4. Fialkow MF, Newton KM, Lentz GM, Weiss NS. Lifetime risk of surgical management for pelvic organ prolapse or urinary incontinence. Int Urogynecol J Pelvic Floor Dysfunct. 2008 Mar;19(3):437-40. doi: 10.1007/s00192-007-0459-9. Epub 2007 Sep 26. PMID: 17896064.