The hip flexors are the muscles at the front of the hip that lift your knee toward your chest. Hip flexor pain is usually felt at the front of the hip and in the crease where the thigh meets the torso, and sometimes into the front of the thigh. It tends to hurt when you actively lift the leg and to ease when you rest. That pattern separates it from hip joint pain.

What are the hip flexors, exactly?

The iliopsoas is really two muscles joined together: the psoas, which runs down from your lower spine, and the iliacus, which starts on the inside of the pelvis. They merge into one tendon that crosses the front of the hip and attaches to a small bump on the inner thigh bone.

The second is the rectus femoris, one of the four quadriceps muscles and the only one crossing both the hip and the knee. That is why sprinting and kicking load it hard.

Where is hip flexor pain felt?

Most people feel it in one of these places:

• The front of the hip, roughly where a trouser pocket sits
• The groin crease, where the thigh folds into the torso
• Deep in the front of the pelvis, hard to point to with one finger
• The front of the thigh, if the rectus femoris is involved
• Sometimes the lower back, because one end of the psoas is anchored to the spine

How do I know if it is my hip flexor or my hip joint?

This is the distinction most often missed. The two sit in almost the same place and behave very differently.

Pain from the hip flexor usually:

• Hurts when you actively lift your knee, especially against resistance
• Flares after sprinting, kicking or a sudden lunge
• Feels sore and fairly localised at the front, near the crease
• Eases within a day or two of backing off the movement

Hip joint pain usually:

• Feels deeper, as though it comes from inside rather than the surface
• Is described as a C shape, curling from the side of the hip into the groin
• Is worse on weight bearing and on turning the leg in or out
• Comes with stiffness and a smaller range of movement

The practical test is who moves the leg. If pain appears only when you drive the movement, a muscle or tendon is the likely source. If it appears when someone else moves your leg, attention shifts to the joint.

What causes hip flexor pain?

A strain is the common one: a sprint, a kick or a lunge that stretches the muscle while it is contracting. Overload is just as common and less obvious, where pain builds over a week or two after a jump in training.

Prolonged sitting leaves the muscle shortened for most of the day. Repetitive loading can irritate the tendon itself, a tendinopathy, which hurts at the start of activity, warms up, then aches afterwards. Snapping hip is different again, where a tendon flicks over a bony ridge with an audible click. It often causes no discomfort at all, but not always.

Why does my hip hurt after sitting all day?

Sitting holds the hip bent for hours. The tissue stops being loaded through its full length, and the first steps afterwards feel stiff and sore at the front. Setting your chair so the hips sit slightly above the knees helps some people, as does standing and walking every half hour.

Honestly, hip pain from sitting is usually about a sustained position, not a muscle that has permanently shortened. Interrupting the position matters more than attacking the muscle.

The problem with blaming tight hip flexors

Tight hip flexors have become the default explanation for anything sore at the front of the hip, and stretching the default answer. Stretching alone rarely resolves it.

If you have stretched diligently for weeks and nothing has changed, that is useful information rather than a sign you are doing it wrong. Pain that ignores stretching is often a strength and load problem, or it is not the hip flexor at all. Our guide to exercises for hip pain at home covers the movement side.

What actually helps

Relative rest comes first: step back from the movement that provokes it rather than stopping everything, since complete rest leaves the tissue weaker.

From there the aim is graded strengthening through range, building tolerance for load while the muscle is long as well as short. A physiotherapist sets the starting point and the progression. Changing how long you sit in one stretch matters too.

When it is not the hip flexor at all

Several other problems produce pain in the same area:

• A hernia, which may show as a groin bulge that changes when you cough
• A labral tear inside the hip joint, which often catches, clicks or gives way
• A stress fracture in the femoral neck or pelvis in runners, which is serious and often missed
• Referred pain from the lower back, travelling into the groin and front of the thigh
• Trouble at the sacroiliac joint, where the pelvis meets the spine

A femoral neck stress fracture can progress if it keeps being loaded, so groin pain in a runner that has worsened over weeks needs assessing rather than pushing through.

What an interventional pain clinic adds

Assessment comes first. Working out whether the pain comes from the muscle, the tendon, the joint or the lower back changes everything that follows.

In selected cases an ultrasound guided injection around the iliopsoas tendon or the bursa beneath it can be used, both to settle irritation and to confirm the source. When the assessment points elsewhere, treatment follows that source instead, whether it is the hip joint or the lumbar spine. Our pages on lumbar radiculopathy and nerve blocks explain those routes.

Warning signs that need prompt or urgent care

Speak to a doctor promptly, or seek emergency care, if you have:

• Groin pain in a runner that worsens over weeks, hurts when you hop, or wakes you at night
• An inability to put weight on the leg
• A hip that is hot and swollen along with a fever
• A visible bulge in the groin that appears or changes when you cough
• Numbness in the groin or saddle area, or a change in bladder or bowel control
• Unexplained weight loss alongside new hip pain

Frequently asked questions

Where is hip flexor pain felt?
At the front of the hip and in the groin crease, where the thigh meets the torso. Some people feel it deeper in the front of the pelvis, and it can spread into the front of the thigh or, because the psoas attaches to the spine, into the lower back.

How long does a hip flexor strain take to settle?
It depends how much of the muscle is involved. Many people with a mild strain find it calms over a few weeks once the aggravating movement is reduced and loading is rebuilt gradually. A larger tear takes longer, and pain unchanged after weeks is worth assessing.

Can sitting all day cause hip flexor pain?
It can contribute. Sitting keeps the hip bent and the muscle shortened for hours, and the front of the hip often feels sore on standing. Usually the sustained position is the problem rather than a tight muscle, so breaking up the sitting helps most.

Why does stretching my hip flexors not help?
Stretching only addresses length, and length is often not what is wrong. If weeks of stretching have changed nothing, the pain may be a strength and load problem, or it may be coming from the hip joint or the lower back. Have it assessed rather than stretching harder.

This article is general information, not medical advice. It cannot diagnose your pain. If your symptoms are new, worsening, or worrying you, speak with your family doctor or contact us for an assessment.

Talk to us about hip flexor pain

If pain at the front of your hip has lasted months and physiotherapy has not shifted it, an assessment can establish which structure is involved. Silver Pain Centre in Toronto offers ultrasound guided injections and assessment of the hip and spine, and most services are covered by OHIP with a physician referral.

Ask your family doctor to send a physician referral, or use our self referral form to start without one.