Why Does the Left Side of My Hip Hurt? Key Causes

Left-sided hip pain stems from the same broad set of musculoskeletal and, occasionally, internal-organ conditions that cause hip pain on either side. In most cases, which hip hurts matters less than where around the hip you feel it: the front (groin area), the outer side, or the back (deep in the buttock). That location is the single best clue to what is going on, because each zone points toward a different family of causes. There are a few situations, though, where left-side-only pain has its own significance, particularly when organs like the sigmoid colon or a pelvic abscess refer pain into the left hip region.

Front, Side, or Back Matters More Than Left or Right

Clinicians sort hip pain into three zones: anterior (front and groin), lateral (outer hip), and posterior (buttock and back of the hip). Anterior pain is often driven by problems inside the joint itself, such as labral tears or osteoarthritis, or by extra-articular issues like hip flexor strain. Lateral pain most commonly comes from the tendons and bursae around the bony prominence on the outside of your hip. Posterior pain tends to involve the deep gluteal muscles, the sciatic nerve, or referred pain from the lower spine.¹ Knowing which of these three zones your pain falls into narrows the list of likely causes far more than knowing it is on the left.

That said, many of these conditions do show up on just one side. Osteoarthritis can progress faster in one hip. A labral tear usually involves a single joint. And certain referred-pain patterns from the abdomen or pelvis are naturally left-sided because the organs responsible sit on the left. So having left-hip-only pain is not unusual and does not, by itself, point to something different from right-hip pain. What it does mean is that something structural or mechanical is probably affecting that side specifically, rather than a systemic process hitting both hips equally.

Lateral Hip Pain and Gluteal Tendinopathy

If the pain lives on the outer bony point of your left hip, the most likely culprit is gluteal tendinopathy, now recognized as the primary driver of what used to be called trochanteric bursitis.² The umbrella term for this cluster of problems is greater trochanteric pain syndrome. It covers irritation or degeneration of the gluteus medius and minimus tendons where they attach to the greater trochanter, along with friction from the iliotibial band that runs over the same area.³

This kind of pain is especially common in women over 40 and in runners. It tends to flare when you lie on the affected side at night, walk uphill, or climb stairs. The tenderness is usually easy to locate: press on the bony bump at the widest point of your hip, and it reproduces the pain. Physical therapy focused on hip-abductor strengthening is the first-line treatment, and structured rehabilitation programs have shown clear improvements in pain and function for people with pre-arthritic hip conditions.⁴

Labral Tears and Femoroacetabular Impingement

Pain that settles deep in the front of your left hip, around the groin crease, often points to something happening inside the joint. Two of the most common intra-articular causes in younger and middle-aged adults are labral tears and femoroacetabular impingement (FAI). The labrum is a ring of cartilage lining the rim of the hip socket that helps keep the ball of the femur seated properly. When it tears, you may feel a deep, catching ache with certain movements, sometimes with an actual clicking sensation. Causes range from trauma and repetitive athletic motion to abnormal bone shape and joint laxity.⁵

FAI is the structural mismatch that often sets the stage for labral damage. If extra bone on either the femoral head or the acetabular rim narrows the joint clearance, the hip pinches during certain movements, especially deep flexion and internal rotation. FAI has emerged as one of the more commonly recognized intra-articular hip problems and is frequently accompanied by a labral tear.⁶ Diagnosis typically requires imaging beyond a plain X-ray; magnetic resonance arthrography consistently outperforms standard MRI for detecting labral pathology.⁷

Osteoarthritis of the Hip

Osteoarthritis remains the most frequently discussed cause of hip pain in older adults, but the relationship between joint wear and pain is surprisingly loose. In a large study of over 4,300 participants, only about 9% of hips in people with frequent pain showed radiographic osteoarthritis, and roughly a quarter of hips with clear X-ray evidence of osteoarthritis were actually painful.⁸ In other words, plenty of people have worn-looking joints on imaging with no symptoms at all, and plenty of people with genuine hip pain have normal-looking X-rays.

When hip osteoarthritis does cause pain, it tends to settle in the groin and sometimes radiates down to the knee. Stiffness in the morning or after sitting is a hallmark. Among patients who present to a primary care doctor with hip or groin pain, about a third show radiographic evidence of osteoarthritis.⁹ Because osteoarthritis often progresses at different rates in each hip, having it only on the left side is common. It does not mean the right hip will inevitably follow.

Snapping Hip Syndrome

Some people notice an audible or palpable snap in the left hip with certain movements. This is snapping hip syndrome, and while it is often painless, it can become painful over time. The snap comes from a tendon or thick band of tissue flicking over a bony structure. It is broadly split into two types: external, where the iliotibial band or gluteus maximus snaps over the greater trochanter, and internal, where the iliopsoas tendon catches against structures at the front of the pelvis.¹⁰

Dynamic ultrasound studies have shown that internal snapping most often results from the iliopsoas tendon suddenly flipping around the iliac muscle and making abrupt contact against the pubic bone.¹¹ An interesting anatomical wrinkle: cadaver research suggests that more than half of people have multiple tendinous insertions of the iliopsoas, which may predispose certain individuals to snapping.¹² If the snapping is painless, it generally does not need treatment. When pain accompanies the snap, stretching, activity modification, and sometimes targeted injections are the usual approach.

Deep Gluteal Syndrome and Sciatic Nerve Entrapment

Pain that sits deep in the left buttock and sometimes shoots down the back of the leg often gets blamed on a “slipped disc,” but a different mechanism can produce an almost identical pattern. Deep gluteal syndrome is a group of conditions where the sciatic nerve gets compressed within the space behind the hip joint, rather than at the spine. This space is crowded with muscles, tendons, and fibrous bands, and any of them can squeeze the nerve.¹³

The best-known version is piriformis syndrome, where the piriformis muscle compresses the sciatic nerve. Estimates suggest piriformis syndrome may account for roughly 5% to 8% of low back pain cases, and it frequently shows up as buttock pain that worsens with sitting or hip rotation.¹⁴ But the broader deep gluteal syndrome concept goes beyond the piriformis: it also includes entrapment by the gemelli-obturator internus complex, ischiofemoral impingement, and proximal hamstring conditions.¹⁵ Because the pain mimics lumbar disc disease so closely, it is frequently misdiagnosed. If spinal imaging looks normal but you have classic sciatica symptoms radiating from one buttock, deep gluteal syndrome deserves consideration.

Sacroiliac Joint Dysfunction

The sacroiliac (SI) joint sits right where the base of the spine meets the pelvis, and when it becomes irritated, the pain typically shows up on one side of the low back and upper buttock. It can feel like hip pain, and it is often confused with lumbar disc problems or true hip joint issues. SI joint dysfunction can be localized to the joint itself and tends to be one-sided.¹⁶

One reason left SI joint pain is worth knowing about is that compensatory muscle changes around the joint, particularly of the gluteus medius on the affected side, can alter how the femoral head sits in the socket and even contribute to femoroacetabular impingement on the same side.¹⁷ So SI joint dysfunction does not just cause pain locally; it can set off a chain of biomechanical problems downstream. This is one scenario where a problem that starts in the pelvis ends up producing what feels like hip-joint pain, even though the hip joint itself is structurally fine.

Stress Fractures of the Femoral Neck

This is the one diagnosis you do not want to miss. Femoral neck stress fractures are uncommon, but they carry serious consequences if they go unrecognized. They should be considered in anyone with exercise-related hip pain, because a delay in diagnosis and subsequent fracture displacement can significantly impair future recovery.¹⁸

The typical story is a runner or military recruit who develops a gradual, deep ache in the front of the groin or hip that is worse with weight-bearing activity and better with rest.¹⁹ Initial X-rays may look normal, which is part of why the diagnosis gets delayed. One case report described a 30-year-old male runner who presented with persistent left hip pain three weeks after a marathon; his X-ray ultimately showed a complete lateral fracture of the femoral neck requiring surgical fixation.²⁰ If you are an active person with worsening groin pain that does not improve with a couple of weeks of rest, pushing through it is the wrong call. An MRI can pick up a stress fracture much earlier than a standard X-ray can.

Avascular Necrosis of the Femoral Head

Avascular necrosis (also called osteonecrosis) happens when blood supply to the ball of the femur is interrupted, causing the bone to gradually die and collapse. It typically presents as progressive hip pain, often starting in the groin and sometimes radiating to the knee. The pain worsens with movement and weight-bearing.²¹ One case described a 36-year-old woman with left groin pain radiating to the knee who was eventually diagnosed by MRI a year after symptoms began, after initial X-rays showed only slight joint space narrowing.²²

The most common cause is trauma, but avascular necrosis is also associated with long-term corticosteroid use, heavy alcohol consumption, sickle cell disease, and certain autoimmune conditions. In some cases the cause is never identified. It affects one hip more often than both, which is why it can present as isolated left hip pain. Because early X-rays may look essentially normal, avascular necrosis is another diagnosis where MRI is the critical imaging step.²³

When an Organ Problem Mimics Left Hip Pain

Here is where the left side of the equation actually matters. Anterior hip pain can sometimes be referred from abdominal or pelvic organs, and several of those organs sit on the left. Sigmoid diverticulitis, which involves inflamed pouches in the lower-left colon, can occasionally produce a psoas abscess that tracks into the hip or thigh and presents as hip pain rather than abdominal pain. One case report documented a patient whose significant abdominal pathology, a retroperitoneal perforation of sigmoid diverticulitis, presented primarily as left hip pain; a CT scan revealed a large psoas abscess tracking into his left lower limb.²⁴

Pelvic abscesses from other causes, such as appendicitis (which sits on the right, but abscesses can migrate) or Crohn’s disease, can similarly abut the iliopsoas muscle and generate referred hip pain. One case involved a patient who could not walk and was found to have a recurrent pelvic abscess extending to the left iliopsoas muscle; imaging showed no intrinsic hip pathology at all.²⁵ These visceral causes are uncommon, but they are the scenario where left-sided pain specifically should raise a different set of questions than right-sided pain would. If your left hip pain is accompanied by fever, unexplained weight loss, abdominal symptoms, or pain that does not change with position or movement, a provider should consider non-musculoskeletal explanations.

Why One Hip and Not the Other

People often wonder whether one-sided hip pain means something is structurally wrong on that side. Sometimes it does: a labral tear, a stress fracture, or a focal area of osteoarthritis affects one joint. But asymmetry in hip loading can also explain why pain localizes to one side. A leg-length discrepancy, even a small one, changes gait mechanics in measurable ways. Research on people with symptomatic leg-length differences after hip replacement found that the affected side showed altered walking patterns: slower gait, reduced stride length, decreased hip range of motion, and substantially altered forces through the hip joint compared to the other side.²⁶

Even without a measurable leg-length difference, habitual movement patterns can load one hip more than the other. If you always carry a bag on the same shoulder, stand with your weight shifted to one leg, or sleep on one side, the cumulative asymmetry adds up. Side sleeping is by far the most common sleep position, and consistently lying on one hip through the night can aggravate lateral hip conditions like gluteal tendinopathy. None of this means the pain is “in your head.” It means the left hip might simply be doing more mechanical work, absorbing more impact, or spending more time in a compressed position than the right.

Inflammatory Arthritis and the Hip

Most hip pain is mechanical, meaning it relates to wear, strain, or structural mismatch. But inflammatory conditions can also target the hip joint, and they sometimes affect one side first. Ankylosing spondylitis is the classic example. It primarily involves the spine and sacroiliac joints but can extend to the hips, and while bilateral involvement is more common over time, unilateral hip arthritis does occur.²⁷ Rheumatoid arthritis and psoriatic arthritis can likewise present with hip pain on one side, though symmetric involvement is more typical as these conditions progress.

What distinguishes inflammatory hip pain from mechanical hip pain is the pattern. Inflammatory pain tends to be worst in the morning, improves with movement, and comes with prolonged stiffness lasting more than 30 minutes after getting out of bed. Mechanical pain, by contrast, tends to worsen with activity and improve with rest. If your left hip pain is at its worst first thing in the morning and gradually eases as you move around, that pattern deserves a conversation with your doctor, especially if you are under 45 or have other signs of systemic inflammation like fatigue, eye redness, or skin changes.

Spinal Problems That Feel Like Hip Pain

The lumbar spine and the hip joint share overlapping nerve pathways, which means problems in one area can masquerade as problems in the other. Lumbar radiculopathy, where a disc bulge or bony spur compresses a nerve root in the lower back, can send pain into the buttock, lateral hip, groin, or leg on one side.²⁸ Some people with lumbar-origin pain never have significant back pain at all; the nerve irritation skips the back and shows up entirely in the hip or leg.

This overlap is one of the most common sources of confusion in diagnosing hip pain. A person may get a hip X-ray that looks normal and assume there is nothing wrong, when the actual generator is a disc problem two vertebrae up. Conversely, someone may get a lumbar MRI showing disc degeneration and assume the back is causing their hip pain, when the hip joint itself is the real problem. The direction of the diagnostic search matters: if hip movements reproduce the pain, the hip joint is more likely at fault; if bending or twisting the lower back triggers it, the spine deserves closer scrutiny. Sometimes both contribute simultaneously, and the frustrating reality is that spinal and hip pathology often coexist, especially in older adults.