Scoping an Impinging Hip, Weighed Against Rehab

Hip arthroscopy or physical therapy for impingement?

For femoroacetabular impingement — a hip in which the ball and socket pinch during movement — the decision between surgery and rehabilitation is unusually balanced. In the largest randomized trial, arthroscopic hip surgery led to modestly better patient-reported hip function at twelve months than personalised, physiotherapist-led conservative care, at substantially higher cost 1Ref 1Griffin DR, Dickenson EJ, Wall PDH, et al. (UK FASHIoN) (2018).Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial.UK FASHIoN RCT: for FAI syndrome, hip arthroscopy gave modestly better patient-reported hip function and quality of life at 12 months than personalised physiotherapist-led conservative care, at substantially higher cost; both groups improved.. Both groups improved; surgery simply improved a little more. That small, real difference is what makes this a genuine decision rather than a foregone conclusion.

For hip impingement, surgery has a modest edge over rehab in the best trial — small enough that a serious course of physical therapy is a reasonable first step, and surgery a sound option if it is not enough.

The balance means the sequence matters. A structured trial of rehabilitation is low-risk, much less expensive, and leaves surgery fully available; and for the people it helps, it removes an operation from the picture. For the people it does not help, the trial loses little and clarifies who is likely to benefit from scoping the hip.

What femoroacetabular impingement is

Femoroacetabular impingement, or FAI, is a mismatch in the shape of the hip joint: extra bone on the ball of the femur, the rim of the socket, or both, so the two surfaces collide at the ends of movement instead of gliding. That repeated contact can pinch the soft tissues, including the labrum that seals the socket, and cause groin pain and stiffness that worsen with deep flexion — squatting, prolonged sitting, or getting in and out of a car 1Ref 1Griffin DR, Dickenson EJ, Wall PDH, et al. (UK FASHIoN) (2018).Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial.UK FASHIoN RCT: for FAI syndrome, hip arthroscopy gave modestly better patient-reported hip function and quality of life at 12 months than personalised physiotherapist-led conservative care, at substantially higher cost; both groups improved..

Femoroacetabular impingement (FAI) is a shape-driven pinching of the hip; the associated pain is called FAI syndrome, and it is diagnosed from symptoms, the exam, and imaging together — not from the bone shape alone.

An important nuance is that the bone shape alone does not equal the condition. Many people have impingement-shaped hips on imaging and no pain at all. FAI syndrome is diagnosed when the shape, the symptoms, and the examination line up, which is why treatment targets the painful hip in front of the clinician rather than a finding on a scan. It is also why the same image can lead to different, equally reasonable decisions in two different people.

What the best trial actually found

The trial that most directly answers this question randomly assigned people with FAI syndrome to either arthroscopic surgery or a personalised physiotherapist-led rehabilitation program, and followed their hip function. At twelve months, the surgical group reported modestly better hip-related quality of life — a difference that was statistically real but on the smaller side — while the conservative group also improved meaningfully from where they started 1Ref 1Griffin DR, Dickenson EJ, Wall PDH, et al. (UK FASHIoN) (2018).Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial.UK FASHIoN RCT: for FAI syndrome, hip arthroscopy gave modestly better patient-reported hip function and quality of life at 12 months than personalised physiotherapist-led conservative care, at substantially higher cost; both groups improved.. Surgery cost considerably more to deliver that additional improvement.

Two honest readings follow, and both are true at once. First, this is one of the clearer signals in favor of a scope operation over conservative care in orthopaedics: FAI is not a condition where surgery is merely a placebo. Second, the margin was modest and the conservative group did well, so choosing rehabilitation first is not choosing an inferior treatment — it is choosing the less invasive, less costly option that helps a large share of people, while keeping surgery in reserve 1Ref 1Griffin DR, Dickenson EJ, Wall PDH, et al. (UK FASHIoN) (2018).Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial.UK FASHIoN RCT: for FAI syndrome, hip arthroscopy gave modestly better patient-reported hip function and quality of life at 12 months than personalised physiotherapist-led conservative care, at substantially higher cost; both groups improved..

It also helps to translate "modest" into something usable. A small average difference across a trial can still mean a lot to one person and little to another; averages hide the spread. For the individual in the room, the practical question is whether a real rehabilitation trial changes their symptoms enough — because if it does, the average surgical edge stops being relevant to them 1Ref 1Griffin DR, Dickenson EJ, Wall PDH, et al. (UK FASHIoN) (2018).Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial.UK FASHIoN RCT: for FAI syndrome, hip arthroscopy gave modestly better patient-reported hip function and quality of life at 12 months than personalised physiotherapist-led conservative care, at substantially higher cost; both groups improved.. Holding both readings prevents the two common distortions: dismissing the surgery as useless, and treating rehabilitation as a mere delay.

Why a FAI hip is different from a shoulder or an arthritic knee

It is worth being precise here, because FAI is often lumped together with other keyhole operations that the evidence treats very differently. In those comparisons, surgery has generally not beaten conservative care — which is exactly why FAI's modest positive result stands out.

• Shoulder impingement. High-certainty evidence shows that subacromial decompression surgery does not provide clinically important benefits over placebo or non-surgical care for rotator cuff-related shoulder pain 2Ref 2Karjalainen TV, Jain NB, Page CM, et al. (2019).Subacromial decompression surgery for rotator cuff disease.High-certainty Cochrane evidence that subacromial decompression surgery does not provide clinically important benefits over placebo or non-surgical care for rotator cuff disease — cited here as a contrast to FAI.. When people ask does shoulder impingement surgery work, the honest answer for this operation is: no better than a sham.
• Degenerative knee. For arthritis-related meniscal tears and mechanical symptoms, a guideline panel issued a strong recommendation against knee arthroscopy for nearly all such patients 3Ref 3Siemieniuk RAC, Harris IA, Agoritsas T, et al. (2017).Arthroscopic surgery for degenerative knee arthritis and meniscal tears: a clinical practice guideline.BMJ Rapid Recommendation: a strong recommendation against arthroscopy for nearly all patients with degenerative knee arthritis and meniscal tears — cited here as a contrast to FAI.. A knee arthroscopy for a degenerative meniscus tear is, for most people, not the answer.

Against that backdrop, FAI is the case where scoping the joint did modestly outperform rehabilitation. That distinction matters: the sequence-of-care message is not "surgery does not work," it is "match the operation to the evidence for that specific problem" 1Ref 1Griffin DR, Dickenson EJ, Wall PDH, et al. (UK FASHIoN) (2018).Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial.UK FASHIoN RCT: for FAI syndrome, hip arthroscopy gave modestly better patient-reported hip function and quality of life at 12 months than personalised physiotherapist-led conservative care, at substantially higher cost; both groups improved.. For a subacromial decompression the evidence says be very cautious; for a well-defined FAI hip, arthroscopy is a legitimate option after rehabilitation has had a fair chance.

What a real trial of rehabilitation looks like

Conservative care for a FAI hip is not rest and hope; in the trial it was a personalised, physiotherapist-led program, and that design is part of why it worked as well as it did 1Ref 1Griffin DR, Dickenson EJ, Wall PDH, et al. (UK FASHIoN) (2018).Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial.UK FASHIoN RCT: for FAI syndrome, hip arthroscopy gave modestly better patient-reported hip function and quality of life at 12 months than personalised physiotherapist-led conservative care, at substantially higher cost; both groups improved.. A meaningful course typically addresses hip and core strength, control of the deep hip muscles, movement retraining to reduce impingement positions, and a graded return to the activities that provoke pain — with the plan tailored to the individual hip rather than a generic sheet of exercises.

How long is a fair trial? There is no universal number, but the principle is that the trial should be genuine and structured before it is judged. An adequate conservative trial usually runs a few months, long enough for strength and control to change, with a clear reassessment point rather than an open-ended wait 1Ref 1Griffin DR, Dickenson EJ, Wall PDH, et al. (UK FASHIoN) (2018).Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial.UK FASHIoN RCT: for FAI syndrome, hip arthroscopy gave modestly better patient-reported hip function and quality of life at 12 months than personalised physiotherapist-led conservative care, at substantially higher cost; both groups improved.. Conservative care duration that is too short — a handful of sessions abandoned early — is not a fair test of rehabilitation, and it is a common reason people conclude, wrongly, that physical therapy failed them.

None of that requires guessing at home. The value of a supervised program is that a clinician can progress the load, correct the movements that pinch, and tell whether the hip is responding — the personalised design the trial rewarded 1Ref 1Griffin DR, Dickenson EJ, Wall PDH, et al. (UK FASHIoN) (2018).Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial.UK FASHIoN RCT: for FAI syndrome, hip arthroscopy gave modestly better patient-reported hip function and quality of life at 12 months than personalised physiotherapist-led conservative care, at substantially higher cost; both groups improved.. If a genuine trial does not deliver, that is useful information, and it is when the surgical conversation becomes concrete.

When surgery for the hip is clearly the right call

Surgery moves toward the front of the line in a few well-defined situations, and naming them is as important as urging patience. For FAI specifically, arthroscopy is a reasonable choice when a genuine, structured rehabilitation trial has not controlled symptoms, when impingement is well-defined on examination and imaging, and when the pain meaningfully limits the life the person wants to live 1Ref 1Griffin DR, Dickenson EJ, Wall PDH, et al. (UK FASHIoN) (2018).Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial.UK FASHIoN RCT: for FAI syndrome, hip arthroscopy gave modestly better patient-reported hip function and quality of life at 12 months than personalised physiotherapist-led conservative care, at substantially higher cost; both groups improved.. A hip labral tear decision often sits inside this same conversation, since the labral damage that accompanies impingement is part of what surgery addresses; the presence of a labral tear on imaging is not, by itself, an automatic reason to operate.

A separate and clearer situation is advanced hip osteoarthritis. Once a hip joint is substantially worn, joint-preserving keyhole surgery is not the right tool, and guidelines describe a shift toward nonsurgical management and, when arthritis is advanced and disabling, joint replacement 4Ref 4American Academy of Orthopaedic Surgeons (AAOS) (2023).Management of Osteoarthritis of the Hip — Clinical Practice Guideline.AAOS hip osteoarthritis guideline: nonsurgical management (exercise/PT, NSAIDs) and, for advanced disabling arthritis, surgical options such as joint replacement.. Distinguishing these is essential: a young, impinging hip with preserved cartilage and an arthritic hip with worn cartilage are different problems with different right answers.

For FAI, surgery earns its place after a genuine rehab trial falls short and the impingement is well-defined. Advanced hip arthritis is a separate situation, where replacement — not a scope — becomes the operation that helps.

The two paths, side by side

Setting the options next to each other shows why reasonable people choose differently. Both improve symptoms; they differ in invasiveness, cost, and the size of the expected gain 1Ref 1Griffin DR, Dickenson EJ, Wall PDH, et al. (UK FASHIoN) (2018).Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial.UK FASHIoN RCT: for FAI syndrome, hip arthroscopy gave modestly better patient-reported hip function and quality of life at 12 months than personalised physiotherapist-led conservative care, at substantially higher cost; both groups improved..

The table is not a verdict. Someone whose pain is tolerable and improving with rehabilitation may reasonably never operate; someone whose well-defined impingement keeps limiting them after a real trial may reasonably choose the modest surgical edge. What the evidence does not support is skipping the rehabilitation trial altogether, given how well the conservative group did 1Ref 1Griffin DR, Dickenson EJ, Wall PDH, et al. (UK FASHIoN) (2018).Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial.UK FASHIoN RCT: for FAI syndrome, hip arthroscopy gave modestly better patient-reported hip function and quality of life at 12 months than personalised physiotherapist-led conservative care, at substantially higher cost; both groups improved..

A sequence-of-care way to decide

A reasonable sequence for most people with FAI syndrome is to begin with a genuine, structured rehabilitation program, reassess at a defined point, and reserve arthroscopy for a hip that stays limited despite that effort. This is not anti-surgery; it follows the evidence, which shows both paths help and surgery helps modestly more, at higher cost and with the risks any operation carries 1Ref 1Griffin DR, Dickenson EJ, Wall PDH, et al. (UK FASHIoN) (2018).Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial.UK FASHIoN RCT: for FAI syndrome, hip arthroscopy gave modestly better patient-reported hip function and quality of life at 12 months than personalised physiotherapist-led conservative care, at substantially higher cost; both groups improved.. Starting conservative honours that balance without closing any door.

The same logic runs through musculoskeletal care more broadly. For a degenerative meniscal tear with arthritis, structured physical therapy matched surgery for functional improvement, so a therapy-first approach is sound there too 5Ref 5Katz JN, Brophy RH, Chaisson CE, et al. (METEOR) (2013).Surgery versus Physical Therapy for a Meniscal Tear and Osteoarthritis.METEOR RCT: in patients 45+ with a degenerative meniscal tear plus knee osteoarthritis, physical therapy matched arthroscopic partial meniscectomy for functional improvement — cited here as a sequence-of-care parallel.; and related decisions — from a torn Achilles, surgery versus no surgery, to lumbar fusion for back pain — increasingly begin with the least invasive effective option and escalate deliberately. Cost is a legitimate part of the picture as well, since arthroscopy is considerably more expensive than a course of physical therapy, and that difference is worth understanding up front.

Both routes for an impinging hip lead to improvement for most people. That takes the panic out of the choice — there is time to try rehabilitation well and decide from there.