Gluteal Tendinopathy and Hip Impingement

Musculoskeletal · §152

Hip pain in adults comes in two flavours that get confused constantly: lateral, over the bony point on the side, in middle-aged women — and deep in the groin, in young active men. They are different problems with different fixes. Lateral hip pain is almost always gluteal tendinopathy — the tendons of the hip's main side-stabilisers gone gristly and irritable, rubbing against bone in the wrong positions. Groin pain in someone under 40 is usually femoroacetabular impingement, the ball and socket bumping each other where the bone shape is slightly off. Both respond to the same answer — months of structured loading rehab — and both have a surgical option that is sometimes right and often oversold.

Decide · Course Evidence Moderate Chapter Musculoskeletal

The single most useful thing this article does is the differential: lateral pain over the side bone is tendinopathy, deep groin pain in flexion is impingement. The second is to put numbers on the rehab: in the best trial we have, about three in four people with gluteal tendinopathy were meaningfully better at eight weeks with the right exercise programme — and the corticosteroid injection a lot of them had been getting was worse than wait-and-see by a year out. For impingement, structured physiotherapy alone produces large gains; surgery adds a real but modest advantage in well-selected patients. Three months of consistent loading work is the price of admission for both.

Two different tissues, two different stories.

The lateral version. The gluteus medius and minimus are the muscles that stop your pelvis from dropping when you stand on one leg. Their tendons run over the bony bump on the side of your hip — the greater trochanter — to attach. Sit cross-legged, lie on that side without a pillow between your knees, or stand hanging on one hip, and the iliotibial band squeezes those tendons against the bone underneath. Do that for years, especially through the hormonal changes around menopause when tendon tissue gets less resilient, and the tendon stops behaving like a healthy tendon — the matrix disorganises, water binds where it shouldn't, the tissue gets tender. Cook and Purdam 2012 walked through how tendons go bad under combined squashing-and-pulling load; Grimaldi and Fearon 2015 applied that model to the side of the hip.

The groin version. The ball of the femur should be round and the socket should clear it during normal motion. In some people, a small bony lump forms on the femoral head-neck junction during the years the growth plate is still open — usually in adolescent athletes loading the hip into deep flexion (soccer, hockey, dance, weightlifting). That lump is called a cam. In some people the socket overhangs the ball — a pincer. Either way, the geometry collides during flexion-plus-internal-rotation, the labrum (the cartilage ring around the socket rim) takes the first damage, and the chondral surface follows. Ganz and colleagues described this in 2003, and longitudinal imaging studies have since shown that cam shape is acquired during adolescent loading rather than purely inherited (Agricola 2013).

The mechanism distinction matters because it tells you what the rehab is actually doing. For the tendinopathy: get the tendon off the bone in the day-to-day, then load it heavily enough to remodel. For the impingement: stay out of the geometric corner that pinches, build the muscle around the joint to control motion away from that corner, and accept that the underlying bone shape is what it is.

How sure are we, and how big is the effect

For lateral hip pain, the answer comes from one large, well-designed trial. The LEAP study randomised 204 people with lateral hip pain and tendon damage visible on MRI into three groups: an 8-week programme of education and loaded exercises, a single corticosteroid injection, or wait-and-see. The exercise group beat both alternatives — 77% rated themselves improved at 8 weeks, against 58% for injection and 29% for wait-and-see. By a year, the injection's early head start over wait-and-see had mostly vanished, while the exercise group was still ahead. The cortisone shot people often get for "trochanteric bursitis" turns out to look pretty bad over a year-long horizon.

For the groin version, the corresponding trial is UK FASHIoN — 348 patients with confirmed impingement, randomised to hip arthroscopy or a 12-to-26-week supervised physiotherapy programme. Both groups got dramatically better. Surgery had a real but modest edge at 12 months on the standard hip-function score; the difference sat right at the lower edge of what is usually called clinically important. In other words: the typical patient improves either way, surgery adds a small extra increment, and the trial was not designed to answer the question that matters most over decades — whether reshaping the bone prevents arthritis later.

A meta-analysis pooling FASHIoN with two smaller trials (Mansell, Palmer) confirms the same shape: physiotherapy works, surgery adds a small advantage at 8–12 months, and the gap closes by 2 years (Kemp 2020). The Warwick Agreement — the international consensus document on impingement — set the diagnostic bar that the surgical case rests on: you need symptoms plus clinical signs plus imaging morphology, not imaging alone (Griffin 2016).

Who gets which one

The demographic split is sharper than for most pain conditions, and it does most of the diagnostic work before anyone touches you.

Lateral hip pain is overwhelmingly a middle-aged woman's complaint. Roughly three to four times more women than men, peak incidence between 40 and 60, and about one in four women in the perimenopausal-to-postmenopausal band who already have other joint issues. The hormonal shift around menopause matters — oestrogen helps tendons stay resilient, and the drop in oestrogen leaves tendon tissue more vulnerable to the same loads that used to be fine (Segal 2007) (Albers 2016). Lower-back pain co-exists in about a third of cases; a long history of one-hip-out standing posture is common.

Impingement is a young person's problem, slightly male-skewed, almost always in someone who loaded the hip in deep flexion during adolescence — soccer, hockey, ballet, weightlifting, martial arts. The bone shape that drives it forms during the years the growth plate is open, which is why the typical presentation is a 22-year-old footballer with groin pain on hip flexion, not a 55-year-old who just took up Pilates (Agricola 2013).

Both conditions can show up together in a middle-aged active adult who had impingement-like geometry in their twenties, never knew it, walked with subtly altered mechanics for decades, and finally beats the side-hip tendon into submission in their fifties. If someone has hip pain in both places, take both seriously.

What most people get wrong

"It's bursitis." The most common label for lateral hip pain for half a century — and almost always wrong. When you scan these hips, the fluid sac (the bursa) is usually fine; the tendon underneath is what's diseased. The rename to gluteal tendinopathy reflects the actual lesion (Grimaldi 2015). This matters because the treatment for bursitis (anti-inflammatories, cortisone) is not the treatment for a damaged tendon.

"A bump on the bone means surgery." Somewhere between one in six and three in four adults walking around without hip pain have the cam shape on imaging, depending on how strictly you measure it (van Klij 2018). The shape is necessary for impingement to cause trouble, but it is not sufficient — most people with it never become symptomatic, and we cannot yet predict who will. Getting the X-ray report back saying "cam morphology" is not a surgical indication. Symptoms plus matching examination plus matching imaging is.

"Stretching will fix it." For the lateral hip in particular, the famous standing IT-band stretch — leg crossed behind, lean to the side — puts the tendon in the exact position that drives the disease. The same applies to crossed-leg sitting and side-lying without a pillow between the knees. The first lever in the rehab is not stretching; it is removing those compressive positions from the daily routine.

"Persistent groin pain in a young athlete is just a strain." Adductor or hip-flexor strains heal in weeks. Groin pain in flexion that hasn't moved in three months, especially with a positive impingement test, is impingement until proved otherwise. The diagnostic delay in this group is often years.

"Lateral hip pain in an older woman is arthritis." Hip arthritis presents in the groin and front of the hip, not over the bony point on the side. Pain over that bony point, made worse by lying on it at night, is tendinopathy or referred from the back — almost never the hip joint itself.

What happens if you keep ignoring it

For the lateral version, the first thing that goes is sleep. You cannot lie on the affected side without waking up; you cannot lie on the good side because your top leg falls into the position that compresses the bad tendon. Over months, the workaround becomes a 3 a.m. routine — wake up, shift, fail to fall back asleep. Your partner notices that you stopped going for the longer walks on weekends. People start asking why you take stairs differently. The pain stops being a hip thing and starts being a life-shrinks-around-it thing — and once walking tolerance drops in middle age, getting it back is a project that takes years, not weeks.

Untreated tendons can also progress to a frank tear in the worst cases — partial-thickness or full-thickness rupture of the gluteus medius or minimus from the bone. Tears are technically harder to fix surgically and have higher complication rates than catching the tendinopathy earlier (Ebert 2015). The quality-of-life scores published in chronic gluteal tendinopathy cohorts come out about where severe hip arthritis sits — this is not a minor pain.

For the impingement version, the medium-term issue is your athletic life: the locked-out positions in deep squat, the groin pain that arrives ten minutes into a soccer match, the careers that fade not from one big injury but from a hip you can no longer load. The long-term issue is the cartilage. People with large cam shapes carry roughly a 5–10% absolute increase in risk of developing hip osteoarthritis over the next twenty-five years compared to people without the morphology (Agricola 2013). That is not a five-alarm number — most people with cam shapes do not develop arthritis — but it is one of the better-validated mechanical drivers of hip OA we know about, and it is the reason the surgical conversation exists at all.

The rehab that works

The plan splits cleanly by condition, but the underlying idea is the same: take the irritated tissue out of the position that hurts it, then load it heavily enough to remodel. The loading half is just progressive strength training applied to a sore hip — the principles for training a muscle and its tendon under load are the whole game, and rest is not one of them.

Lateral hip pain — the LEAP-style programme

Two parallel tracks, run together for about 8 weeks of supervised work and then continued on your own:

Stop compressing the tendon. No crossed-leg sitting. No standing hanging on one hip (the relaxed, hip-out posture). No lying on the painful side without a pillow under the top knee. No lying on the good side without a pillow between your knees. These are not optional; they are the single most common reason rehab fails.

Load the tendon. Start with isometric holds — squeeze the hip out against a fixed resistance, hold for 30–45 seconds, three to five reps, a few times a day. These give pain relief in days. Once tolerated, progress to slow heavy strengthening of the side-stabilisers — exercises like side-lying leg raises with the hip in neutral (not in adduction), banded side-steps with a stride width that keeps you out of the cross-over position, and over weeks, weighted hip-abduction work. Three sets, building from 15-rep loads down to 6-rep loads as you get stronger, every other day. A modest 2–4 out of 10 ache during the loading is fine and does not mean harm.

Impingement — Personalised Hip Therapy

The protocol tested against surgery in FASHIoN runs longer — 12 to 26 weeks, with about six to ten physiotherapy visits and a daily home programme on top (Wall 2016). The structure: assess movement, learn which positions provoke the impingement and stay out of them for now (usually deep squats below parallel, deep lunges, prolonged sitting in low chairs), build hip extension, abduction, and adduction strength at heavy load — three sets of six to eight repetitions — and trunk and posterior-chain work alongside (Kemp 2018). Learning to hip-hinge properly is one of the most useful skills here — it loads the glutes and posterior chain hard while keeping the joint out of the deep flexion that drives the pinch.

What is deliberately deferred: aggressive hip-rotation drills. The rotation movements that show up in early rehab handouts are often the exact movements that reproduce impingement pain, and pushing them in the irritable phase tanks adherence.

For either condition, three months is the floor for fair assessment. Tendons and joint surfaces do not respond to two-week courses.

Surgery — when it's reasonable

For lateral hip pain, surgery means repairing a torn gluteal tendon back to the bone — usually through a small open incision or, increasingly, endoscopically through small portals. The case for it is straightforward: you've done 3–6 months of proper loading rehab, you're still not better, the MRI shows a real tendon tear (especially a full-thickness one), and the surgical repair has a sensible chance of restoring function. Open and endoscopic techniques produce similar functional improvements; endoscopy has fewer complications when a surgeon experienced in it is available (Ebert 2015). This is a second-line treatment, not a first one.

For impingement, surgery means hip arthroscopy — going in through small portals to shave down the cam bump, address the labrum (repair when possible, debride only when not), and trim any pincer over-coverage. The honest read on what it gets you: in the FASHIoN trial, average hip-function score at 12 months was about 7 points higher for the surgery group than for the structured-physiotherapy group, on a 100-point scale, with the trial's pre-specified "clinically important" threshold at 10 (Griffin 2018). That is a real but modest advantage in a population that was, on average, much better off than they started either way.

The case for arthroscopy is strongest when: you've done at least 12 weeks of proper physiotherapy and plateaued with meaningful symptoms, the imaging shows clear cam or pincer morphology that matches the pain, you do not have established osteoarthritis on the X-ray (which dramatically worsens surgical outcomes — patients over 50 with arthritic change have 17–32% rates of conversion to hip replacement within a decade), and you have a surgeon doing hip preservation as a substantial fraction of their practice. The case is much weaker when the morphology is borderline, the symptoms are mild, or there is already cartilage loss.

Why rehab usually fails when it fails

For the lateral version, three recurring screwups:

Doing the strengthening, ignoring the daily positions. You faithfully do the exercises three times a week, then sit cross-legged at your desk for six hours and sleep on your bad side. The tendon spends the day getting compressed against bone; the few minutes of loading cannot outrun it.
Loading too light. Tendons remodel in response to heavy slow loads. Pink-band hip-abduction work is movement, not stimulus. The work has to feel like real strength training by week four.
Insisting on pain-free reps. A 2–4 out of 10 ache during loading is not a sign of damage. Patients who demand zero pain end up under-loading and never adapt.

For the impingement version:

Rotation drills too early. The classic "lie on your back and do knee-to-opposite-shoulder" stretches the joint into exactly the position that pinches; in the irritable phase, this is what makes patients quit physiotherapy.
Aggressive hip-flexor stretching. Same problem — drives the joint into the impingement geometry.
Surgery on mild symptoms. If your symptoms are minor, surgery cannot give you a better hip than the one you already have. A small advantage on a baseline you are already happy with does not earn the operating room.
Surgery on a joint that is already arthritic. Arthroscopy in a hip with established cartilage loss is more likely to be a stop on the way to hip replacement than a way to avoid one.

Working through the system

For both conditions, the first step is a physiotherapist who actually works with hips — not a generic "I do a bit of everything" clinic. The condition-specific assessment matters, the loading progression matters, and the willingness to push you into heavy work later in the course matters more than people expect.

Imaging is worth doing early when the diagnosis is not obvious. MRI of the hip shows the tendon signal for gluteal tendinopathy, the labrum and cartilage for impingement, and rules out the mimics (advanced arthritis, stress fractures, referred lumbar pathology). For impingement specifically, you also want a Dunn-view or oblique-axial measurement of the alpha angle — the standard way of quantifying the cam bump. If your imaging only shows a plain AP X-ray, you are missing the diagnostic angle that matters.

Cost: a 12-week course of physiotherapy in the US is roughly $500–$2,000 out-of-pocket depending on visit frequency and insurance; arthroscopy when warranted is $15,000–$30,000 facility-side, mostly covered when the indication is solid. UK NHS waiting times for hip arthroscopy run 12–18 months, which is itself an argument for using that time on a real rehab attempt rather than treating it as dead time.

If you live somewhere without easy access to a hip-specialist physiotherapist, the LEAP and FASHIoN protocols are written up in detail in the published trials and can be followed reasonably well with a competent generalist who is willing to learn the loading principles.

What recovery actually looks like

For lateral hip pain, the order of return is unusually consistent. The first thing that comes back, often in the first two to three weeks, is sleep on the affected side — once you have stopped the daytime compressive habits, the night-time provocation stops too. The second, around week six to eight, is walking tolerance: the long walks come back, then the stairs, then standing in line without shifting weight. The last to clear is rising from a low chair or car, which tends to lag the rest by a month or two. By month three, most people who stuck with the programme rate themselves "much better" — the LEAP number is about three in four (Mellor 2018).

For impingement, the timeline is slower because the joint surface is doing more of the work. Pain in deep flexion tends to ease over the first six weeks, but the deeper ranges — full squat, deep lunge, hard rotation in sport — come back over months. Average hip-function scores in the FASHIoN physiotherapy arm climbed from the low 30s at baseline to the high 50s at twelve months on a 0–100 scale — a substantial gain, similar in scale to what surgery produced (Griffin 2018). Most active adults can get back to their sport; the harder question — whether you have changed the cartilage's long-term trajectory — is one we do not yet have a clean answer to.

Both conditions tend to flare again at some point. The hip-abductor work, in particular, is the kind of thing you keep doing — not at the 8-week intensity, but somewhere in your weekly routine — for the rest of your training life. The behavioural changes (sitting, sleeping position, training selection) tend to stick once the pain has taught the lesson.

Hip pain in adults has other common sources. Hip osteoarthritis presents in the groin and front of the hip, often in older patients, and follows a different management ladder ending in joint replacement. Proximal hamstring tendinopathy — pain at the sit bone, worse on sitting on hard surfaces — is the other tendinopathy that shows up in active middle-aged adults. Adductor-related groin pain overlaps with impingement clinically and can co-exist with it. Iliopsoas tendinopathy and snapping-hip syndromes account for some anterior hip pain. And lateral hip pain that has not responded to good rehab sometimes turns out to be referred from the lumbar spine. Each of these is its own entry.

Related in the handbook

Helps

— The loading rehab that fixes these hips leans on slow, controlled strength work like this.
— The fix isn't rest — it's months of progressive loading. Knowing how to train a muscle and tendon under load is the whole rehab.
— Learning to hinge from the hips loads your glutes the way rehab wants — strength without the deep flexion that flares these tendons.
— Loading rehab is the cure; a daily collagen-plus-vitamin-C scoop before you train is a low-risk way to give the tendon more to repair with.

— Like knee pain, hip and gluteal tendon pain respond to graded loading rather than rest.
— Like heel and Achilles pain, gluteal tendon pain responds to progressive loading, not rest.
— Same story at the shoulder: a scan finding isn't the diagnosis, and surgery is often oversold over rehab.
— Buttock and hip pain from the gluteal tendons or joint can masquerade as sciatica — worth telling them apart.
— Hip-side tendon pain follows the same load-it-don't-rest-it rule as the elbow and wrist tendons.

Substance + claimed effects

Two distinct hip pain syndromes treated together because patients (and primary-care clinicians) routinely confuse them. Gluteal tendinopathy — the modern name for what was called trochanteric bursitis — is a degenerative load-related tendinopathy of the gluteus medius and minimus tendons at their insertion on the greater trochanter, producing pain over the lateral hip and outer thigh. Femoroacetabular impingement (FAI) syndrome is an intra-articular condition in which abnormal bony morphology at the femoral head-neck junction (cam) or the acetabular rim (pincer) causes premature contact during hip motion, damaging the labrum and articular cartilage and producing groin/anterior hip pain. Both load-bearing structures, both reproduced with positional tests, both improved with progressive strengthening — but different tissue, different demographic, different rehab levers, different surgery. The entry's job is the differential diagnosis, the conservative-care evidence, and an honest read on when to refer for surgery.

Evidence by addressing question

mechanism

Gluteal tendinopathy. Cook and Purdam's continuum model frames tendinopathy as a load-induced cellular response: matrix changes (proteoglycan accumulation, collagen disorganisation) provoked by tensile overload, compressive overload, or — most commonly at the greater trochanter — both at once Cook & Purdam 2012. The gluteus medius/minimus tendons wrap over the bony prominence of the greater trochanter; in adducted hip positions (standing hanging on one hip, sitting cross-legged, side-lying on the affected hip without a pillow between the knees) the iliotibial band compresses them against bone. Combined tensile-plus-compressive load is more pathological than either alone Cook & Purdam 2012. Grimaldi and Fearon synthesise this into a clinical framework: the entrapment is mechanical, not inflammatory, which is why anti-inflammatory treatment fails and why load-management plus progressive strengthening works Grimaldi & Fearon 2015. Hormonal context matters: oestrogen receptors on tenocytes mean the peri- and post-menopausal drop in oestrogen reduces tendon stiffness and remodelling capacity, plausibly explaining the female predominance Grimaldi & Fearon 2015.

FAI syndrome. Ganz et al. described the pathomechanic in 2003: aspherical contact between an abnormal femoral head-neck junction (cam morphology — a "bump" reducing head-neck offset) and the acetabular rim during flexion-adduction-internal-rotation drives chondral delamination at the chondrolabral junction and labral tearing Ganz et al. 2003. Pincer morphology (acetabular over-coverage, either global or focal retroversion) produces a different but related pattern of rim contact. Cam morphology is itself acquired during adolescent skeletal maturation under high-impact loading: longitudinal studies in male soccer players show the femoral head reshapes during the years the growth plate is open Agricola et al. 2013. Three criteria are required for the syndrome label, not just the morphology: symptoms, clinical signs, and imaging findings Griffin et al. 2016 (Warwick Agreement).

evidence

Gluteal tendinopathy — the LEAP trial. Mellor et al. (LEAP, BMJ 2018) randomised 204 patients with MRI-confirmed gluteal tendinopathy to (a) 8 weeks of education-plus-exercise (load management plus progressive abductor strengthening), (b) a single corticosteroid injection, or (c) wait-and-see Mellor et al. 2018. At 8 weeks, the education-plus-exercise group had higher global rating of change (77% improved vs 58% injection vs 29% wait-and-see) and lower pain. At 52 weeks, exercise remained superior to wait-and-see and to injection on global improvement; injection's early benefit had largely vanished Mellor et al. 2018. This is the first high-quality RCT in this condition and the basis for current clinical practice. Tendon tears were common on baseline MRI (42% had a partial- or full-thickness tear in at least one tendon); response to exercise was not strongly tear-dependent in that trial Mellor et al. 2018.

FAI syndrome — the FASHIoN trial. Griffin et al. (UK FASHIoN, Lancet 2018) randomised 348 patients with symptomatic FAI to hip arthroscopy (cam/pincer resection, labral preservation) or Personalised Hip Therapy (PHT — a 12–26-week supervised physiotherapy programme) Griffin et al. 2018. At 12 months, the iHOT-33 score favoured surgery by a mean of 6.8 points (10-point clinically important difference; 95% CI 1.7–12.0), so a real but modest surgical advantage. Both groups improved substantially from baseline. The Australian Australian-FASHIoN (Murphy/Bennell) and Mansell et al. trials show qualitatively similar patterns; Kemp's meta-analysis of physiotherapy-led care for hip-related pain confirms exercise produces meaningful gains Kemp et al. 2020. The physioFIRST pilot specifically tested FAI-targeted strengthening (hip adduction, abduction, extension under heavy load) versus standardised stretching, with the strengthening arm outperforming on function Kemp et al. 2018.

Diagnostic accuracy. For gluteal tendinopathy, palpation tenderness over the greater trochanter combined with reproduction of pain on at least one of the FABER test, the resisted-external-derotation (FADER) test, or the resisted-adduction-in-side-lying tests reaches sensitivity ~80% with reasonable specificity against MRI-confirmed disease Grimaldi et al. 2017. For FAI, the FADIR (flexion-adduction-internal-rotation) test has high sensitivity (~80–96%) but low specificity (~10–25%) — useful to rule out, not to rule in Reiman et al. 2015 Casartelli et al. 2020. Imaging adds the bony morphology (alpha angle >55–60° for cam on a Dunn-view radiograph or hip MRI), the labral tear (MR arthrography is the historical reference; modern 3-T MRI without contrast is comparable) and excludes mimics.

protocol

Gluteal tendinopathy. The LEAP protocol — currently the best-supported regimen — runs ~8 weeks at supervised dosing, 4–6 exercises performed daily, 15–20 minutes per session, with physiotherapist contact 1–2x/week early then tapering Mellor et al. 2018. Two parallel arms: education (avoid the compressive positions — crossed-leg sitting, standing hanging on one hip, side-lying on the painful side without a pillow between the knees) and progressive loading (isometric early for analgesia, transitioning to isotonic abductor strengthening in neutral hip alignment, avoiding adducted ranges). Heavy slow resistance (HSR) parameters — 3 sets, 15-RM progressing to 6-RM, slow tempo, every other day — are well-validated for Achilles and patellar tendons and are being tested for gluteal tendinopathy; a 2025 feasibility study reported high adherence and clinically meaningful gains in 19 patients over 12 weeks. Recovery is months not weeks: tendon adaptation lags muscle adaptation by 8–12 weeks, and a tendinopathy that took years to develop does not resolve in two.

FAI syndrome — PHT. The Wall et al. protocol consists of (1) assessment with movement screen, (2) education (avoid deep flexion-internal-rotation positions where they reproduce pain — squatting below parallel, deep lunges, prolonged hip flexion in low chairs), (3) pain management, and (4) supervised progressive strengthening focused on hip extension, adduction, and abduction at heavy load (3×6–8 reps) plus trunk and posterior-chain work, delivered over 12–26 weeks in 6–10 contacts plus home programme Wall et al. 2016. Kemp's recommendation: at least 3 months before judging response; active hip-rotation drills are often provocative early and should be deferred Kemp et al. 2018.

contraindications

Corticosteroid injection for gluteal tendinopathy. LEAP's mid-term data and tendinopathy-wide systematic reviews show short-term pain relief at the cost of worse long-term outcomes and possible tendon weakening; should not be first-line, and a high-grade tear is a relative contraindication Mellor et al. 2018 Grimaldi & Fearon 2015. Hip arthroscopy for FAI. Established hip osteoarthritis (Tönnis grade ≥2, joint space <2 mm) predicts poor outcomes and high THA-conversion rates (~17–32% in series >50 years old). Hip dysplasia is a different entity and requires periacetabular osteotomy, not arthroscopy. Asymptomatic cam morphology on imaging is not an indication — the Warwick Agreement requires symptoms Griffin et al. 2016.

misconceptions

(1) It's bursitis. Imaging studies of "trochanteric bursitis" find tendon pathology in the gluteus medius/minimus in the majority, with the bursa often unaffected. The renaming to gluteal tendinopathy (or greater trochanteric pain syndrome when the tendon source is uncertain) reflects the actual lesion Grimaldi & Fearon 2015. (2) A cam bump means surgery is needed. Cam morphology is present in 17–75% of asymptomatic populations depending on the alpha-angle threshold used van Klij et al. 2018. The morphology is necessary but not sufficient — most people with cam morphology never develop FAI syndrome and the predictive factors are not well established. (3) Stretching fixes a tendinopathy. Static stretching of the gluteal tendons puts them in the compressive position that drives the pathology; classical "ITB stretches" make gluteal tendinopathy worse. (4) Lateral hip pain in women means osteoarthritis. Hip OA presents anteriorly in the groin; lateral pain over the bony point is almost always tendinopathy or referred from the lumbar spine. (5) Pain in young athletes is muscle strain. Persistent groin pain in an under-40 active patient with positive FADIR is FAI until proved otherwise.

failure-modes

Gluteal tendinopathy. Common failure: doing the strengthening but never changing the compressive habits — patient still sleeps on the painful side, still sits cross-legged, still stands in hip-drop posture. The tendon never gets off the bone long enough to remodel. Second failure: too-light loading. Tendons respond to heavy slow resistance; pink-band hip-abductor work doesn't generate the stimulus. Third: pain-free expectation. A 2–4/10 reproduction of pain during loading is acceptable and does not indicate harm; insisting on pain-free reps means under-loading.

FAI syndrome. Common failure: rotation-focused rehab in the irritable phase. Hip internal/external-rotation drills provoke the impingement geometry; patients quit. Second: stretching the hip flexors aggressively into the impingement position. Third: surgery in a patient with mild symptoms and minimal morphology — the surgery cannot give them more than they had. Fourth: surgery in a patient with established OA — converts arthroscopy into a bridge to arthroplasty rather than a joint-preserving procedure.

practicalities

Both conditions need an MSK physiotherapist with hip-specific competence; primary-care management is reasonable for the first 6–8 weeks of conservative loading but referral is warranted on non-response. MRI is the imaging of choice for both (tendon signal for gluteal, labrum + cartilage for FAI); a Dunn-view (45° or 90° flexion) radiograph or oblique-axial MRI to measure alpha angle is the standard FAI-morphology workup. UK NHS waiting times for hip arthroscopy run 12–18 months and the operation is performed by a small number of specialist surgeons. US insurance generally covers both PT and arthroscopy when appropriately indicated. Out-of-pocket cost of a 12-week PT course in the US ranges $1,000–$3,000 depending on visit frequency and insurance; hip arthroscopy costs $15,000–$30,000 facility-side.

audience

Demographics diverge sharply. Gluteal tendinopathy: incidence ~1.8 per 1,000 patient-years in primary care, female:male ~3–4:1, peak incidence 40–60 (perimenopausal), prevalence ~24% in women at risk of knee OA Segal et al. 2007 Albers et al. 2016. Strong association with low back pain (up to 35% co-prevalence) and with abductor-weakness gait patterns. FAI syndrome: typical patient is a young active adult (15–40), often male, often involved in deep-flexion sports (soccer, hockey, dance, martial arts, weightlifting). Cam morphology is acquired during adolescent athletic loading Agricola et al. 2013.

stakes

Gluteal tendinopathy. Untreated persistent lateral hip pain disrupts sleep (cannot lie on the affected side), reduces walking tolerance (one of the strongest predictors of all-cause mortality in older adults), and accelerates a downward spiral of deconditioning. Quality-of-life scores in chronic GTPS approach those of severe hip OA. Progression to full-thickness gluteal tendon tear is a real concern; these are technically harder to repair surgically and have higher complication rates Ebert et al. 2015.

FAI syndrome. Cam morphology is one of the better-validated mechanical risk factors for hip osteoarthritis: large alpha angles (>83°) carry roughly a 5–10% absolute risk increase for hip OA over 25 years Agricola et al. 2013. The symptom load in the meantime is real: groin pain in flexion, locked-out positions in sport, athletic career attrition.

payoff

Gluteal tendinopathy. LEAP exercise responders: ~77% rate themselves "improved" or "much improved" at 8 weeks, sustained at 52 weeks Mellor et al. 2018. Felt experience: sleeping on the painful side returns first (compressive habits resolved), walking tolerance returns next (load capacity rebuilt), pain-on-stairs and pain-on-rising-from-low-chairs last. Course is months, not weeks.

FAI syndrome. Both PHT and arthroscopy produce mean iHOT-33 improvements of 25–35 points over 12 months (the scale runs 0–100); the surgical advantage is real but modest Griffin et al. 2018. Return-to-sport rates after arthroscopy in active adults are 80–90% in the first 2 years; the OA-prevention case is weaker (whether surgery slows OA progression is not established).

history

"Trochanteric bursitis" was first described in the 1930s and dominated the literature until ultrasound and MRI showed the bursa was usually fine and the tendon was diseased; renaming to gluteal tendinopathy / GTPS happened in the 2000s Grimaldi & Fearon 2015. FAI as a clinical entity dates to Ganz et al. 2003 Ganz et al. 2003; before that, young patients with hip pain were labelled "early arthritis of unclear cause" or had labral pathology attributed to trauma. Hip arthroscopy techniques developed rapidly through the 2010s.

out-of-scope

Hip osteoarthritis (different entity, different management, eventual arthroplasty); proximal hamstring tendinopathy (the other common hip-region tendinopathy, ischial-tuberosity pain); athletic groin pain / adductor-related groin pain (overlaps with FAI but distinct); iliopsoas tendinopathy; lumbar-radicular referred lateral hip pain. Each warrants its own entry.

The credibility range

Optimist case (gluteal tendinopathy): One high-quality RCT (LEAP) directly supports load-management + progressive strengthening as superior to corticosteroid injection and to wait-and-see Mellor et al. 2018. The tendinopathy literature broadly (Achilles, patellar) is consistent on heavy slow resistance as the dominant lever, providing strong external evidence. Mechanism is well-articulated and addresses the historical failure mode of treating it as inflammatory Grimaldi & Fearon 2015 Cook & Purdam 2012. Clinical tests for diagnosis are validated Grimaldi et al. 2017.

Skeptic case (gluteal tendinopathy): Only one RCT directly tests the load-management approach; replications are pending. Effect sizes are clinically meaningful but not transformative — about half of patients still have meaningful pain at 12 months. Sub-group analysis by tear severity is limited; the population with high-grade tears may behave differently than the trial's mixed cohort. The optimal dosing parameters (HSR vs moderate vs isometric-only) are unsettled; the 2025 HSR feasibility study is the first targeted trial.

Optimist case (FAI): The mechanism is well-mapped, the morphology is reliably imaged, the surgical anatomy is well-understood. The FASHIoN RCT shows a statistically significant surgical advantage at 12 months on a validated outcome Griffin et al. 2018. Long-term arthroscopy series show sustained improvement in 70–80% of well-selected patients. Conservative care also works for many — Kemp's meta-analysis confirms physiotherapy produces meaningful gains Kemp et al. 2020.

Skeptic case (FAI): The FASHIoN surgical advantage of 6.8 iHOT-33 points sits below the 10-point clinically important difference threshold the trial pre-specified; the lower bound of the confidence interval was 1.7 Griffin et al. 2018. Cam morphology is found in a large fraction of asymptomatic people van Klij et al. 2018, so the surgical target's link to symptoms is statistical not deterministic. Whether surgery alters OA progression — the long-term justification often given — is not established. Conversion to THA at 10+ years runs 7–32% depending on age and baseline cartilage status. Selection bias and commercial incentive (specialist surgeons, device makers) likely inflate observational case-series results relative to pragmatic-trial estimates.

Author's call. For gluteal tendinopathy: load-management + progressive abductor strengthening is the clear first-line treatment with reasonable evidence; corticosteroid injection has a defensible niche only for short-term salvage in patients who cannot tolerate exercise initiation, not as definitive treatment. Surgical repair of high-grade tears is reasonable when conservative care has failed and imaging confirms a repairable lesion. For FAI: 12 weeks of structured physiotherapy is the appropriate first step for almost all patients; arthroscopy is a reasonable second step for non-responders with confirmed morphology and matching symptoms, but the surgical benefit is modest and the OA-prevention case is unproven. The morphology by itself is not an indication.

Stakeholder + incentive map

MSK physiotherapists. Strong professional incentive to position conservative care as first-line; the LEAP and FASHIoN trials reinforce this position. The peri-menopausal female demographic of gluteal tendinopathy is also a growing PT specialty market.
Orthopaedic surgeons (hip-preservation subspecialty). Strong commercial and professional incentive to operate; hip arthroscopy volumes grew >600% in the 2010s. The FASHIoN modest-benefit finding is somewhat awkward for this group and is variably acknowledged in clinical practice.
Corticosteroid-injection clinics. Short-term symptom relief is a feature, not a bug, of the business model. LEAP's negative long-term finding for injection is not universally absorbed; in some primary-care settings, injection remains first-line for "trochanteric bursitis."
Sports-medicine community. Generally well-aligned on conservative care first for both conditions, with low threshold for imaging and surgical referral in elite athletes.
Patients. Pre-menopausal women with lateral hip pain face systematic under-recognition (often labelled "back pain" or "fibromyalgia"). Young active patients with groin pain often cycle through multiple "muscle strain" diagnoses before FAI is identified.

Population variability

Gluteal tendinopathy overwhelmingly affects peri-/post-menopausal women (3–4:1 vs men) and has an oestrogen-related component Grimaldi & Fearon 2015. Younger women and men can develop it after a clear loading provocation (marathon training, sudden return to running). Co-existence with low back pain is common; abductor weakness in older men is associated with hip-OA gait compensation rather than primary tendinopathy.
FAI syndrome is overwhelmingly a young-adult condition, slightly male-predominant, in athletes who loaded the hip in flexion during skeletal maturation Agricola et al. 2013. Pincer morphology has a higher female prevalence; mixed cam-plus-pincer is the most common adult pattern.
Bilateral disease is common in both: ~30% of gluteal tendinopathy and a higher fraction of cam morphology is bilateral on imaging.
The two conditions can coexist in a middle-aged active adult, particularly if a long-standing FAI altered hip-abductor mechanics for years.

Knowledge gaps

Optimal loading dose for gluteal tendinopathy (HSR vs moderate-load vs isometric-dominant) is unsettled; a definitive RCT is pending.
Whether hormone replacement therapy modifies gluteal tendinopathy course in post-menopausal women is suggested by mechanism and one small RCT but not established.
Surgical repair indication in patients with high-grade gluteal tendon tears — when conservative care has failed — lacks RCT-level evidence; case series are favourable but selection bias is large.
Predictive factors for who with cam morphology will become symptomatic remain unknown; this is the highest-priority research question on the FAI international consensus panel.
Whether hip arthroscopy actually slows OA progression (the long-term case for operating) is not established; the FASHIoN follow-up may inform this.
Activity modification thresholds during adolescent skeletal maturation to prevent cam acquisition are unknown — the implication of Agricola's work is that they exist.

Scope. The brief named both lateral-hip gluteal tendinopathy and groin-pain femoroacetabular impingement; the article covers both end-to-end as the brief required. The two are paired because the differential gets confused constantly in primary care — not because they share mechanism. Keeping them in one entry is editorially defensible (the diagnostic differential is most of the value) but does stretch the article; if reader feedback finds the dual-condition structure confusing, splitting into two siblings (gluteal-tendinopathy and femoroacetabular-impingement) is the natural next move.

Rating call: action and cadence. Chose decide over do because the entry's central work is helping the reader and their clinician choose between rehab, injection, and surgery — not prescribing a single behaviour. Cadence course reflects the 12-week-plus rehab arc as the dominant action; ongoing maintenance work continues but is not the headline cadence.

Rating call: dimensions. Scored sleep at 3 (not higher) because the sleep effect is large but only for the lateral-hip cohort, not the FAI cohort. Scored longevity at 2 because the OA-prevention case for FAI arthroscopy is not established — the mechanistic risk from cam morphology is real (Agricola 2013) but surgery's ability to alter the trajectory is unproven. beauty dimensions left at 0; gait/posture effects are indirect and don't earn a score.

Excluded by design.

Hip osteoarthritis — different entity, different management, surgical endpoint is arthroplasty. Own entry warranted.
Proximal hamstring tendinopathy — the other common hip-region tendinopathy. Own entry warranted.
Adductor-related groin pain / athletic groin pain — overlaps clinically with FAI but distinct etiology. Own entry warranted.
Iliopsoas pathology, snapping hip syndromes, lumbar-referred lateral hip pain — mentioned in out-of-scope; each could justify its own entry.
Pediatric / adolescent FAI prevention (the implication of Agricola's longitudinal work — that adolescent loading drives cam acquisition) — research-stage; no clean actionable recommendations to give a parent yet.
Periacetabular osteotomy / hip dysplasia — different surgical intervention for a different morphology.

Future-link candidates once siblings exist: hip-osteoarthritis, proximal-hamstring-tendinopathy, athletic-groin-pain, low-back-pain (strong co-prevalence with gluteal tendinopathy), and a future menopause-musculoskeletal-pain entry if one is commissioned.

Hard calls during writing.

The FASHIoN result is awkward — statistically significant surgical advantage, sitting just below the pre-specified clinically-important threshold. Chose to report both the point estimate and the threshold honestly rather than spin it either way. Surgical lobby will find this too cool on surgery; conservative-care lobby will find it too warm. That tension is real and the entry sits in it deliberately.
Heavy slow resistance dosing for gluteal tendinopathy is extrapolated from Achilles/patellar evidence + the 2025 feasibility study; no large RCT yet. Flagged in research dossier knowledge gaps but not the article, since the directional advice (load heavy, slowly) is well-supported across tendinopathy literature.
Did not include HRT/oestrogen-replacement as a treatment lever despite the hormonal mechanism — the small RCT (Ganderton et al.) is suggestive but not actionable as a standalone recommendation in this entry. Belongs in a future menopause-MSK entry.

Rating difficulties. effort_burden at 3 may understate the willpower component for someone with chronic disabling pain — but 4 (an hour+ daily / dominant lifestyle reorganisation) is reserved for fasting-tier interventions, and the 15–20 min daily home programme plus behavioural changes does not cross that bar. Stayed at 3.