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Core Muscle Injury (CMI)

A core muscle injury most commonly occurs in athletes who play sports with a lot of kicking or frequent speed changes, like soccer, football and hockey. It has been called many things over the years – a sports hernia, slap-shot gut, athletic pubalgia and Gilmore groin, among others. As diagnostic technology has gotten better, we have been able to determine that a CMI is not a true hernia.

What is a core muscle injury?

A CMI is an injury to the abdominal muscle and thigh muscle (adductor longus). They attach in the same spot, on the pubic bone, but pull in opposite directions. Force and repetitive motion can tear the attachment, causing a core muscle injury.

To request an appointment with a sports medicine specialist, call 913-574-4878 or toll-free 855-898-9275.

Core muscle injury symptoms and risks

The most common symptom of a CMI is deep, chronic pain in the groin or lower abdominal muscles. The pain often resolves when you’re resting but flares up when exercising. The most extreme pain occurs when you make explosive movements or sudden changes in direction.

Men and boys are more likely to get a core muscle injury. Females make up about 5-15% of CMIs.

You’re also more likely to get a CMI if you are younger. This is likely due to the aggressive nature and competitive level of athletic activities in your youth, teens and 20s.

Core muscle injury diagnosis and screening

Your doctor will start with a physical exam. Then they will work to rule out a hernia. This is usually done with imaging, like ultrasound or MRI. An MRI is preferred for diagnosis because it is more sensitive and specific.

Core muscle injury treatment

Treatment always starts with conservative measures. That includes, rest, activity modification, anti-inflammatory medications and physical therapy. If those are successful, you may go into an exercise program focused on stretching and strength to prevent another CMI.

If you are still having pain with the conservative treatment, you may get a corticosteroid injection.

The last option is surgery. There are a variety of approaches for surgery. Some surgeons will cut nerves to relieve the pain and put in a mesh implant. Others may fix the tendon back to the bone and do an adductor release.

At The University of Kansas Health System, orthopedic surgeon Scott Mullen, MD, has pioneered a type of adductor longus tenotomy. In this surgery, he releases the tendinous portion of the attachment. Most of the thigh muscle stays attached to the pubic bone – about 75% – but releasing it eliminates the tension, or pulling, between the 2 muscles. He then sews the abdominal muscle back to the pubis. This method repairs the tear and releases tension.

Any surgery must be followed with a physical therapy program. Generally, athletes can return to their sport 6-8 weeks after surgery if they have done appropriate rehab.

Why choose us for core muscle injuries

The University of Kansas Health System is a leader in the diagnosis and treatment of core muscle injuries. Our team includes musculoskeletal radiology, using a specific MRI protocol to scan patients at the beginning of their journey. This ensures you rule out a hernia and get proper treatment.

We have expert surgeons who can address the full scope of a core muscle injury with unique, exacting methods. The adductor longus tenotomy and core muscle repair Dr. Mullen performs is not available anywhere else in the region. Additionally, Dr. Mullen can perform hip arthroscopy to treat the core muscle injury, hip impingement and labral tear while under the same anesthesia. This avoids needing multiple surgeries. It also leads to better outcomes when compared to addressing only one problem.

Finally, our large team of sports medicine physical therapists and specialists will guide you through surgery recovery, into rehabilitation and finally to return to your sport.

Our team of highly trained doctors, surgeons and staff is equipped to deal with the special needs and focus of athletes. We provide the highest level of care for all athletes. The same doctors who care for the Kansas City Royals and the Kansas City Chiefs will care for you.

Your core muscle injury care team