August 11, 2020

By Emeline Mugisha, M.S.N., M.P.H., R.N.

Many women experience various birth-related aches and pains. While hip pain during and shortly after delivery is common, chronic postpartum hip pain from sources such as labral tears is less understood. So, there are some unknowns about these particular injuries, including how many moms experience them. Fortunately, we know that labral tears are treatable and sometimes preventable, and we also know a lot about postpartum conditions that affect the hip overall.

What are acetabular labral tears?

The hip is a joint formed by the top of your thigh bone (femoral head) and the cup-shaped area of your pelvic bone (acetabulum). The acetabular (hip) labrum is a ring of thick, soft tissue that covers the acetabulum. The hip labrum has several functions, including protecting the padding that covers the femoral head, providing hip stability and weight-bearing functions, and easing the forces applied to your hip. In a nutshell, it helps your hip move smoothly without problems or pain.

An acetabular labral tear is any damage to the ring that makes up the hip labrum.

What are the symptoms of hip labral tears?

A torn hip labrum can feel and look different for each mom. Some moms with labral tears may have no symptoms. However, for most, these tears cause discomfort.

Symptoms primarily occur in the hip or groin and may include:

• Deep hip or groin pain
• Constant dull or aching pain
• Intermittent episodes of sharp pain
• Weakness in your hip muscles
• Pain that worsens with activities of daily living (ADLs), walking, sitting, climbing stairs, standing, recreational activity, or sex
• Holding your hip with your hand in the shape of a “C” (known as the C-sign)
• A locking or catching sensation

What causes hip labral tears?

Causes of hip labral tears include:

• Pregnancy-related weight gain
• Loosening of the hip joints as a result of a hormone (relaxin) released in pregnancy
• Changes in posture during delivery
• Pre-existing conditions of the hip and pelvis

Both weight gain and loosening of the hip joints are regular changes during pregnancy. In contrast, labral tears that result from delivery positions are preventable. These injuries often arise when a well-meaning birth assistant unintentionally pulls the ankle outward during delivery. Thus, slight position changes that ensure that the ankle is free from the hold of another person so that the hip can freely rotate comfortably may reduce injury.

How do I know if I have a hip labral tear?

Any doctor can diagnose a torn hip labrum. To begin, your doctor will perform a health history and physical examination. If you may have a labral tear, they will order one or more imaging scans, such as an MRI or arthrogram (a scan after injection into the joint). They may also suggest a diagnostic injection or an arthroscopy to help confirm your diagnosis.

A diagnostic injection involves injecting an anesthetic into the hip joint. If the injection entirely relieves your pain, it confirms the hip joint is the source of your pain. Arthroscopy is a surgical procedure that involves inserting a small camera into your joint to look for damage.

A specialist in musculoskeletal injuries will help you and your doctor to determine the cause of your symptoms. Specialists such as orthopedists and physiatrists diagnose and treat similar conditions. However, unlike orthopedists, physiatrists do not perform surgery.

What can you do to treat hip labral tears?

Thankfully, some labral tears do not require treatment. If problems persist, there are various therapies available for you, depending on the severity of your symptoms:

• Medications. Over-the-counter (OTC) medications such as ibuprofen may help relieve pain. While considered safe during breastfeeding, it's essential to speak with your doctor about which OTC pain relievers are safe for you and your baby.

• Physical therapy (PT). A PT can teach you exercises to help restore pain-free functioning of your hip and prevent re-injury.

• Injections. Injection of corticosteroids into the hip may provide temporary pain relief.

• Surgery. If your pain continues for more than six months with other interventions, an orthopedist's surgical repair of the injury is an option.

Are there other causes of postpartum hip pain?

Besides labral tears, other causes of postpartum hip pain may include:

• Pregnancy and lactation-associated osteoporosis (PLO). Osteoporosis is a condition in which your bones become weak and easier to break. PLO is rare but increases the risk of fractures in your hip (femoral bone) or its surrounding bones.

• Sacral stress fractures. These fractures occur when the sacrum (the bone between your hips) breaks, and typically cause pain that is both easy to ignore and treat.

• Piriformis syndrome. This complication is a rare cause of sciatica in the hip region. "Sciatica" refers to a sharp pain that results from a pinched sciatic nerve. The sciatic nerve extends from your lower back, through your hips and buttocks, and down both legs. The piriformis is a small muscle in your buttocks. Piriformis syndrome may occur after pregnancy when this muscle spasms and places pressure on your sciatic nerve.

• Infection. Though rare, infections of the hip (such as osteomyelitis) may also occur.

Sources:

Baker, J., Mcguire, C., & Mulhall, K. (2010). Acetabular labral tears following pregnancy. Acta Orthopaedica Belgica, 76(3), 325–328. https://www.researchgate.net/profile/Ciara_Mcguire/publication/45602506_Acetabular_labral_tears_following_pregnancy/links/00463521bb523041b6000000.pdf

Brooks, A. G., & Domb, B. G. (2012). Acetabular labral tear and postpartum hip pain. Obstetrics & Gynecology, 120(5), 1093–1098. http://10.1097/AOG.0b013e31826fbcc8

Garner, Ginger. (2014, March 27). The postpartum hip: Are new moms at higher risk for acetabular labral tears? Herman & Wallace. https://hermanwallace.com/blog/the-postpartum-hip-are-new-moms-at-higher-risk-for-acetabular-labral-tears

Lee, K. S., Kong, S., Kim, J., Kim, T., Choi, C. B., Kim, Y. S., & Lee, K. H. (2015). Osteomyelitis of bilateral femoral heads after childbirth: A case report. Annals of Rehabilitation Medicine, 39(3), 498–503. https://doi.org/10.5535/arm.2015.39.3.498

Roller, R. L., Walker, E. A., & Michelitch, S. W. (2015). Postpartum sacral fracture in a 30-year-old female. Radiology Case Reports, 4(3), 264. https://doi.org/10.2484/rcr.v4i3.264

Sivrioglu, A. K., Ozyurek, S., Mutlu, H., & Sonmez, G. (2013). Piriformis syndrome occurring after pregnancy. BMJ Case Reports 2013. https://doi.org/10.1136/bcr-2013-008946



Emeline Mugisha, M.S.N., M.P.H., R.N. - Emeline Mugisha is an award-winning, master's-prepared nurse with over a decade of experience in community/public health and clinical health services at the field and management levels. She has co-authored two professional manuscripts in Women's Health Issues and the Journal of Midwifery and Women's Health. She has an M.S. in Public Health Nursing and an M.P.H. from Johns Hopkins University.