No matter which type of hip flexor pain you have, they all can be unpleasant and limit your ability to move, especially any movement that involves repetitive hip flexion like walking and climbing stairs. The pain can even make getting out of bed in the morning excruciating. The burning sensation or a sharp pain can be felt in your groin, lower abdominals, somewhere along the front of your waistline, or a combination of these symptoms.
Having experienced severe hip flexor pain in 2005 that lasted what seemed like a month—it started the day after I took a Brazilian capoeira class in San Diego—I tried different treatments to get rid of the pain. This included stretching, foam rolling, and lots of rest. Although they provided very short relief, the pain persisted and refused to go away. Fortunately, the pain gradually fizzled out without needing to take pain medication regularly or to see a doctor or physical therapist. I never take getting out of bed for granted ever again, nor did I take another capoeira class (I still enjoy watching it and listening to the music.).
Hip flexor pain is an umbrella term that covers several types of anterior hip pain. These include iliopsoas syndrome, groin pain, hip tendonitis, iliopsoas bursitis, and hip flexor strain. Not everyone may recover like I did, but what should we know about hip flexor pain and whether the treatments for it are effective or not?
Anatomy and biomechanics of the hip flexors
The iliopsoas consists of three muscles that allow you to flex and externally rotate your hip: iliacus, psoas major, and psoas minor. Getting in and out of your car or getting off your bicycle would involve both of these movements. The muscles also help you laterally flex your torso and bend your torso at your hip, like when you bow or deadlift.
The iliacus is a fan-shaped muscle that extends from the iliac fossa of the pelvis and inserts in the lesser trochanter of the femur. Some of the iliacus’s muscle fibers stem from the anterior sacroiliac and iliolumbar ligaments, which bridges the pelvis and lower spine. The iliopsoas bursa separates the iliopsoas tendon from the hip joint, allowing the iliopsoas to move smoothly.
Located behind the abdominal wall, the psoas major originates from the transversus processes of the T12 to L5 of the lower thoracic spine and the first four vertebrae of the lumbar spine. Like the iliacus, it inserts into the lesser trochanter, merging with the iliacus behind the inguinal ligament. The lower part of the iliopsoas for a part of the femoral triangle, which makes the upper third of the thigh.
The psoas minor sometimes gets overlooked because it is smaller than the other two hip flexors, and it provides limited support for movement. It originates from the lateral sides of T12 and L1 and inserts into the iliopublic eminince and pecten pubis of the pubic bone.
Some clinicians do not consider the psoa minor to be part of the iliopsoas because not everyone was born with this muscle. One study of 44 cadavers found some differences in its existence between young Black (91% do not have it) and White men (13%). One Indian study in 2010 found that 70% of the 30 cadavers the researchers had dissected do not have a psoas minor.
These muscles are surrounded by the iliac fascia that separates the inguinal ligament and the pelvis into two sections: the lateral side that consists of the iliacus, psoas major, and femoral nerve and the medial side that allow the femoral blood vessels to travel through.
Innervation of the iliopsoas stem from the lumbar plexus that branch out from the lumbar spine to various hip muscles. The femoral nerve (L2-L4) connects to the iliacus while the anterior rami of the spinal nerves (L1-L3) connects to the psoas major.
Causes and risk factors of hip flexor pain?
Sometimes it is difficult to find a specific cause of a type of hip flexor pain. You might be driving and whistling to work one day, and when you get out of your car, you feel a sharp pain near your groin and you have no idea why that happened. That pain may persist throughout the day and into the weekend, and you pray that it does not become chronic. Other times, the cause is more obvious, like when you fall while skiing or strain a muscle while you practice knee strikes in a krav maga class.
While it is tempting to blame the cause of hip flexor pain to one source, you should be aware of the different types of hip pain so that you can communicate with your physician or physical therapist better should you seek medical help.
Hip flexor strain
A hip flexor strain is a tear in the muscle fibers, and it is categorized into three primary grades.
Grade I: This involves minor tears in the muscle fibers; hip flexors still have some range of motion and function with less than 10 degree deficit. Patients should be able to continue a physical activity or sport immediately after the injury.
Grade II: There is greater tear in a number of muscle fibers “without complete muscle rupture.” Range of motion is decreased by 10 to 25 degrees, and patients could not continue the sport or physical activity.
Grade III: This is a complete muscle rupture where patients often are in severe pain with more than a 25% loss of range of motion.
This grading system is based on the research of various scientists and clinicians since 1966, and many have attempted to refine the definition and diagnosis. While much of these research do not pertain to hip flexors, clinicians should be able to extrapolate this information when treating hip flexor pain.
Hip flexor tendinitis
Tendinitis is the inflammation of a tendon often caused by the friction between the tendon and another organ, such as a muscle, a bursa, or another tendon. In some cases, an injury could also cause tendinitis. Thus, it is likely that the tendons of the psoas major can get inflamed from overuse or other causes. Compared to other types of tendinitis, like the knee and the shoulder, there is not much research that examines the effectiveness of treatments and the nature of hip flexor tendinitis.
One hypothesis is that hip arthroscopy surgery may increase the risk of getting hip flexor tendinitis. However, a few studies do not support this idea. One study by Adid et al. examined medical records of 252 qualified patients who had undergone hip arthroscopy surgery who were tested for tendinitis in their hip flexors and had regular follow-ups over five years post-op. Only 60 patients (24%) showed one symptom relating to hip flexor tendinitis in the iliopsoas. However, the study did not specify if any of these patients had pain or not.
They concluded that iliopsoas tendinitis “is an under-diagnosed, under-reported complication after hip arthroscopy that can restrict the post-operative rehabilitation course if not addressed properly.”
Another study from Shanghai, China, compared 133 patients with total hip arthroplasties for hip dysplasia with 126 patients with the same surgery without hip dysplasia. The researchers found no differences in the number of incidences between both groups, but the artificial femoral head may irritate the iliopsoas which may increase the risk of getting tendinitis.
Snapping psoas and iliopsoas bursitis
You may have heard a dull click or popping sound in your hip when you walk or raise your leg up when you are lying on your back. Sometimes it can be painful and limit your ability to flex your hip.
The snapping psoas—sometimes called internal hip snapping or snapping hip syndrome—was once thought to be caused by the snapping motion of the iliopsoas tendon over the iliopectineal eminence of the pelvis when you flex your hip. However, studies in the 1970s to the 2000s proposed that there may be multiple causes of hip snapping, such as the snapping of the iliopsoas tendon over the less trochanter or the femoral head of the femur and the “sudden flipping” of the psoas tendon over the iliacus.
Sometimes the regular snapping may cause symptomatic hip bursitis where the iliopsoas bursa may likely get inflamed. Although some research finds a lack of bursa abnormalities among patients who undergo surgery for painful snapping psoas, some researchers coined the term “iliopsoas syndrome” to include a variety of symptoms and causes.
Iliopasoas syndrome (psoas syndrome)
When the exact cause of hip flexors pain is unknown and the pain seems to spread throughout the anterior hip area. The source of pain may stem from a combination of iliopsoas tendinitis, snapping psoas and bursitis, and iliopectineal bursitis.
Like tendinitis and strains, overuse of the hip flexors may be the primary cause of iliopsoas syndrome, followed by hip arthroscopy, rheumatoid arthritis, and osteoarthritis.
Hip flexor pain symptoms
While much of the symptoms of hip flexor pain overlap among different causes, there are some commonalities. Oftentimes, patients may feel in the front of their hip when they stand up from a sitting position. Some may feel a “catching” sensation when they flex a knee to 90 degrees from a standing position. Back pain and gluteal pain are also symptoms, but these are difficult to distinguish from more common causes of these two types of pain.
Other symptoms include tenderness in the insertion of the iliopsoas by the less trochanter, decreased range of motion in hip extension, and too much lumbar lordosis. Patients are likely to be unable to perform hip flexion movements well without pain, such as climbing stairs, kicking, and walking.
Sometimes the pain is not from the psoas or iliacus but from visceral pain, such as appendicitis, diverticulitis, prostatitis, and colon cancer.
If you have some of the symptoms, check with your physician or physical therapists for your own personal diagnosis and treatment.
Tight hip flexors: Is this a sign of dysfunction?
There is little research that examines whether shortened or tight hip flexors cause or are associated with low back pain, yet many manual therapists and personal trainers seem to take this as a fact. Google “tight hip flexors” and you would likely see that the first two pages consist mostly of citing hip flexors as a cause for low back pain, hip pain, and other types of pain.
While research in this specific topic is lacking, some evidence indicates a weak or no association between tight hip flexors and low back pain.
One major research on this was published in the Upsala Journal of Medical Sciences in 1988 where about 600 young men, who were enlisted in Swedish military service, were examined at the beginning and during the service over a four-year period. Researcher Ann-Lisa Hellsing concluded that “Tight hamstring or psoas muscles could not be shown to correlate to current back pain or to the incidence of back pain during the follow-up period.”
She mentioned that having tight muscles could stem from other factors, such as genetics, heavy strength training, long-term pain, and poor movement patterns. The study also shows a lack of back pain relief from stretching tight psoas and hamstrings.
While there has been very little research since Hellsing’s work that examines this specific relationship, indirect evidence from postural studies also support her findings. For example, a large Iranian study in 2002, which compared 600 men and women in their twenties to fifties with or without low back pain, found no association between body structure and posture (e.g. leg length discrepancy, lordotic curve, iliopsoas length) with low back pain.
A 2014 systematic review and meta-analysis of 43 studies that compared movement and lordosis angle found no differences between people with low back pain and those without. Because lordosis is often associated with the anterior pelvic tilt—where the iliopsoas are “shortened”—this does affirm that shortened or tight hip flexors is a cause or strong association with low back pain.
Hip flexor pain treatments
Aside from pain medications, conservative treatments such as exercise and manual therapy may have some effectiveness for hip flexor pain. Because there are different causes of hip flexor pain, no single treatment is a cure-all. Always consult your physician or another healthcare provider if your hip flexor pain is chronic or severe, impeding your daily activities and sleep.
Hip flexor stretching
Stretching may provide some temporary relief of hip flexor pain, like most stretches for other body parts, even though research showed that static stretching for low back pain and neck pain showed mixed results. It is likely that different individuals and populations may have different responses to stretching. Thus, there is no one-size-fits-all answer to whether stretching will work for you or not.
Standing hip flexor stretch
Stand with your right foot in front of you and your left behind you. Turn your left foot inward slightly so that it points toward your right heel. With your hands on the sides of your hips, shift your weight forward and contract your left buttock slightly so that you should feel a stretch in your left hip flexors and thigh.
Raise your left arm over your head to increase the stretch. Hold the stretch for 20 to 30 seconds. Repeat the stretch on your opposite side.
3D hip flexor stretch
The “3D” implies the three planes of motion that you can use for the hip flexor stretch.
From the previous stretch with your left arm extended over your head, lean your torso to your right until you feel a stretch on your sides. Hold this position for 20 to 30 seconds.
While maintaining the lean, turn your torso to your left as much as you can or at least you feel a “twisting” stretch in your hip flexors. Hold this position for 20 to 30 seconds. Repeat the stretch on the other side.
You can also do this stretch from a kneeling position.
Hip flexor strength exercises
There is limited scientific evidence that examines whether strength exercises can help reduce or manage hip flexor pain or not. One randomized-controlled trial with 33 healthy, female athletes finds that strength training of the hip flexors may be “promising for future prevention and treatment of acute and longstanding hip-flexor injuries.”
Given that exercise, in general, has some analgesic effects, perhaps almost any type of strength training exercise can help alleviate the symptoms of hip flexor pain—similar to low back pain studies where no type of exercise is superior to another for reducing pain.
If your current hip flexor pain does not impede your ability to exercise or do your daily actives, and your physician says it is okay for you to exercise, then
Supine knee ups with band
For beginners, you can start by lying on the floor on your back with your legs together. Then bring your knees toward your chest and straighten your legs back to the starting position.
When this gets easier, progress to raising one or both legs straight to the air. Bring your knee as close to your body as possible and return to the starting position.
For another level up, try the exercise like in this video below. All movements are done in a controlled manner, so no swinging.
Standing hip flexion with band
Running high knees
For a more advanced level, this exercise can help improve strength and power production and motor control of your hip flexors, legs, and other hip muscles.
Tip: If you are an athlete who is recovering, and you can perform basic movement patterns without pain, train more specifically for the sport that you are playing or performing. This is based on the SAID principle (specific adaptation to imposed demands), which simply means that your body and brain will get better at specifically what you train it to do.
For example, a soccer kick is different from kicks in taekwondo and other martial martial arts. If you are a soccer player, you would practice kicks and footwork that is what you actually do in a game. Practicing roundhouse kicks and high kicks may benefit little for you, based on the SAID principle (unless you are also training for a martial art).
There are different types of surgeries for different hip flexor pain, which is beyond the scope of this article.
However, it is worth noting that some studies find improvements in surgical techniques that reduce “complications” among patients post-surgery. A 2016 review on iliopsoas pathology finds that open surgeries to lengthen or release the psoas major that is rubbing against the iliopsoas bursa have a rate of 21% of complications versus 2.3% with arthroscopic surgery. Recurrence of the snapping hip syndrome among those cases with open surgeries has a rate of 23% compared with 0% of arthroscopic surgery cases.
Despite the success rate of arthroscopic surgeries for this type of hip flexor pain, numerous studies on surgeries for low back pain, knee pain, and shoulder pain have shown that they are not that much different than sham surgeries. Whether or not this would apply to hip flexor pain is currently unknown.
Hip flexor pain and massage therapy: considerations of “deep tissue” treatment
Like with most patients’ and clients’ conditions, manual therapists need a complete health history before they start a treatment. Rachel Ah Kit, who is a remedial massage therapist and clinic director at Bodyworks Massage Therapy in Christchurch, New Zealand, said that the history must also include psychosocial factors, such as stress, work, sleep, and family problems. The history should also include potential physical injury that contributes to the hip flexor pain and down the front of the thigh.
“Clients with anterior hip pain, who say they have issues with iliopsoas, have often self-diagnosed with Dr. Google or they have been told that’s the problem by a well-meaning friend, or even a physiotherapist. It’s not a muscle the general public are usually aware of.”
Pain following a fall or impact involving excessive hip rotation, with reports of pain after long periods of sitting, standing or walking, should be assessed for a labral tear, which may or may not be associated with femoroacetabular impingement (FAI).
“Therapists can make a quick hip assessment with a FADDIR test (Flexion, ADDuction, Internal Rotation), with the client in supine with the hip and knee passively flexed to 90 degrees, and then adducting and rotating the hip medially,” Ah Kit explained. “Any sharp hip or groin pain, clicking or guarding on medial rotation may indicate a labral tear, FAI, or ‘snapping hip’ (where the iliopsoas tendon snaps over the pelvic bone) and clients should be referred out for a diagnosis, imaging, and/or rehab management.”
Such tests without a diagnosis are within the scope of practice of remedial massage therapists in New Zealand, but therapists should refer out to a physiotherapist or physician if clients report pain when they medially rotate their hip while standing. Massage therapists must check their local and national laws to see if such manual testing is within their scope of practice.
“Regardless of outcome the client can still be treated conservatively with massage therapy,” Ah Kit said.
“Pain is a biopsychosocial experience. So from a biological perspective, considering the joints, muscles, the nervous system, motor control and coordination, as well as cardiovascular and lymphatic systems,” said physiotherapist Antony Lo, who practices at The Physio Detective at Oatley, New South Wales, Australia. “These are important, but that’s not the whole picture.”
When treating patients, Lo emphasizes the patients’ beliefs, attitudes, meaning, and stories—or “BAMS,” as he calls it. These underlying issues can also contribute to the pain experience, even though they seem to be unrelated health issues.
“And that’s just for the hip region itself,” Lo said. “There are also referred pain sources and other issues which can cause anterior hip pain.
“It is so much easier to provide a simple test and answer with a solution but the reality is far from the truth.”
Lo cautioned that tests do not always tell the therapist or the patient about the cause of the hip flexor pain. He gave the Thomas Test as an example.
“The Thomas Test is considered valid for testing hip extension, but it doesn’t tell you why,” he said.
In a 2016 paper by Vigotsky et al., the researcher found that the Thomas Test is unreliable to measure hip extension unless the therapists account for the position of the lumbar spine and pelvis. Even so, using pelvic landmarks, such as the anterior and posterior superior iliac spines, are not reliable because different people have variations of bony landmark positions. Thus, the textbook standard for finding “neutral pelvis” is unreliable and therapists may likely make a wrong diagnosis and treatment plan.
“They blame the muscle for things like postural problems, leg length discrepancies, and even menstrual cramps,” Johnston said. “However, with what we know about modern research around musculoskeletal injuries, much of that is not only false, it is also harmful when it is communicated to a patient.”
He mentioned a 2010 review that suggested reassurance, education, exercise, and (some) manual therapy when treating patients with low back pain and hip pain.
“It should be no different when treating someone with anterior hip, or psoas pain,” Johnston said.
Providing reassurance to the patient and showing them they are not broken or have some other pathological abnormality because of their psoas (like “tight” iliopsoas) is one way to help reduce their pain.
“Educating them about where the psoas is, how it works, and why it isn’t doing all the things these other blogs are talking about is also a crucial aspect of helping someone.”
In terms of exercise, simple isometrics for hip flexion can help reduce pain, Johnston suggested. However, “building resilience” is what exercise therapy can also do, which shows patients how capable and strong they are. “Also doing some movement on the opposite side of the body like glute bridges can help with not just pain reduction but with movement in general,” Johnston said.
Some massage therapists believe they can target the psoas muscles to massage. However, basic anatomy shows that it is not very likely for most people. Therapists would have to “go through” layers of tissues and organs to reach the psoas major.
“We might be able to provide some relief to patients with techniques that involve the application of pressure to these areas, but not because we are ‘frictioning’ these deep structures,” Jason Erickson said in a Facebook forum, who is a massage instructor in Eagan, Minnesota.
Johnston used to think that he could dig his fingers into a patient’s abdominal region and “palpate and treat” the psoas muscle. “We can’t actually press deep enough where we are making direct contact with muscles, even when we put a person in the right position and resist hip flexion,” he said. “We can’t effectively push through organs and other tissues that sit on top of the psoas to be able to treat and palpate it effectively.”
“When we are delivering manual therapy to a patient, the biggest influence we have is through the skin and the nervous system,” Johnston added. “What we can do is touch the general area nicely to influence the nervous system to bring about change and help their pain. Doing this in combination with reassurance, education, and exercise will bring about the greatest benefit for the person on the table in front of you.”
“Treating the iliopsoas is usually done with the client supine, and the knees and hips slightly flexed over a bolster or large pillow,” Ah Kit said. “The belly of the iliopsoas cannot be easily accessed, despite what some therapists may believe. Deep work superior and medial to the ASIS can be extremely uncomfortable for the client because there is pressure on the ascending or descending colon.
“The femoral attachment can be more easily accessed at the lesser trochanter, with the hip and knee flexed and abducted. Therapists should still work with caution here as it is located within the ‘femoral triangle,’ bounded by the inguinal ligament, sartorius and adductor longus muscles and contains the femoral artery, femoral vein and femoral nerve therapists should always be aware of, and work away from the femoral pulse.
Rather than doing deep tissue massage and other types of massage that promotes aggressive force on the tissues, Ah Kit suggests a “more pleasant and less invasive treatment”—an approach based on dermoneuromodulation (DNM) that addresses the nervous system and skin.
“It is possible that pain in the area may be also related to restriction of the femoral nerve where it emerges medially to the ASIS and below the inguinal ligament,” Ah Kit said. “Using skin stretch techniques described by Diane Jacobs in her book, the area superficial to the iliopsoas attachment can be treated before attempting any deeper work.”
Because hip flexor pain is complicated like most types of joint pain—and it is difficult to prove— Lo suggested that manual therapists should approach clinical interactions with patients with a scientific mindset. This would include using inductive reasoning, a way of thinking about how likely something would happen. There could be other reasons that cause hip flexor pain that clinicians might overlook.
“It is far too easy to find information that confirms what we think,” Lo said. “Therefore, if I honestly think it is the iliopsoas muscle that is causing the problem, I will try to prove it is everything else first. Only then will I settle on [the] iliopsoas [to be] the primary contributing factor.”
Perhaps this is one reason why I did not seek help when I had hip flexor pain more than 15 years ago. The last thing I wanted was to pay and spend time on a treatment that may or may not work. Given there is fewer quality research on hip flexor pain than other joint pain like the knee and shoulder, the best approach so far, as Johnston said, is to take the pain research in other areas and apply it to the hip flexors.
“If we could all approach our clinical interactions with this scientific mindset, then we are much more likely to have empowered and motivated patients who can make better decisions based on good quality information,” Lo said.