Scope of This Review
This page reviews the published evidence on hip osteoarthritis and on cell-based treatments for it. Two things shape everything below and are worth stating at the outset.
The hip is not the knee. Most of the cell-therapy evidence in osteoarthritis was generated in knee joints, and it does not transfer to the hip automatically. Where this page uses knee data, it says so.
Osteonecrosis of the femoral head is a different condition from hip osteoarthritis — with a different mechanism, a different treatment approach, and a substantially better evidence base. It is covered separately below, because conflating the two would misrepresent both.
Living With Hip Osteoarthritis
Hip osteoarthritis changes how a day is organised before it changes anything visible. Stairs get counted. Walking routes get chosen by surface and gradient. Putting on socks becomes a manoeuvre. Night pain disrupts sleep, and the fatigue that follows makes everything else harder to manage.
It is common. In the Framingham community cohort — 978 adults aged 50 and over, recruited regardless of whether they reported joint pain — age-standardised prevalence of radiographic hip osteoarthritis was 19.6% (95% CI 16.7–23.0%), and of symptomatic hip osteoarthritis 4.2% (95% CI 2.9–6.1%) [1]. A 2024 review of hip osteoarthritis estimates it affects 9.2% of people over 45 worldwide [4].
The gap between those two Framingham figures matters more than either number. Most hips that look arthritic on an X-ray do not hurt, and imaging findings correlate imperfectly with symptoms. Osteoarthritis is a clinical diagnosis, and imaging is widely over-used in making it [10].
What Happens Inside the Hip Joint
The hip is a ball-and-socket joint: the femoral head articulates with the acetabulum. Articular cartilage covers both surfaces, providing near-frictionless movement and load distribution, and a fibrocartilaginous labrum deepens the socket.
Osteoarthritis is a disease of the whole joint, not just cartilage wear [11]:
- Matrix degradation — matrix metalloproteinases break down collagen and proteoglycans faster than chondrocytes rebuild them [12]
- Chondrocyte senescence — the cells that maintain cartilage lose function and accumulate in a senescent state [13]
- Subchondral bone remodelling — bone beneath the cartilage thickens and forms cysts, contributing to pain and stiffness [14]
- Synovitis — the joint lining inflames, producing effusion and inflammatory cytokines, and correlates with symptoms [15]
- Altered TGFβ signalling — a central regulator whose behaviour changes in ageing and osteoarthritic joints [16]
The Kellgren-Lawrence grades
After Kellgren and Lawrence, 1957 [17]
Two caveats a patient should know. The Kellgren-Lawrence system was developed and validated principally on knee and hand radiographs; its use in the hip is a later convention. And grade does not determine treatment on its own — symptoms, function and what has already been tried matter at least as much [10].
Conventional Treatment: What It Does and Does Not Do
Exercise, education and weight management are the core recommended treatments for hip osteoarthritis in international guidance [9], and they are not a placeholder while waiting for something better. Guideline bodies place them first because they have the evidence.
Oral NSAIDs relieve pain but do not alter disease course. In a randomised trial of over 24,000 arthritis patients, celecoxib, naproxen and ibuprofen carried comparable cardiovascular risk, with meaningful gastrointestinal and renal risk on long-term use [18].
Corticosteroid injections give weeks of relief. In a two-year randomised trial against saline — in knees, not hips — intra-articular triamcinolone produced greater cartilage volume loss with no significant pain benefit at 24 months [19]. Whether that finding applies to the hip has not been established, but it is a reason for caution about repeated injection.
Hyaluronic acid, PRP and other injections. This is where the hip evidence is unusually clear, and unusually discouraging. A 2026 systematic review and network meta-analysis examined 14 studies and 1,254 participants across eight injection types — corticosteroid; low, high and ultra-high molecular weight hyaluronic acid; PRP; corticosteroid plus hyaluronic acid; PRP plus hyaluronic acid; and placebo or standard care. No injection type showed a statistically significant difference from placebo in WOMAC total or VAS at 3, 6 or 12 months [5].
Note what is not in that network: MSC therapy. It could not be included, because there are no hip MSC randomised trials to include.
Cell Therapy for Hip Osteoarthritis: The Honest Position
How MSCs are thought to work
Mesenchymal stromal cells can differentiate into cartilage, bone and fat lineages, but their therapeutic effect in osteoarthritis is understood to come mainly from paracrine signalling rather than tissue replacement — secreting anti-inflammatory and trophic factors that modulate the joint environment [20]. They are immune evasive rather than immune privileged: allogeneic cells can be given without donor matching, but they are cleared by the recipient and their evasiveness is conditional [21].
What has actually been studied in hips
No randomised controlled trial of MSC therapy for hip osteoarthritis has been published. Three systematic reviews cover the field, and their scale is the finding:
The individual studies underneath are correspondingly small. A representative example: six consecutive patients with Tönnis grade 0–2 hip osteoarthritis received an intra-articular injection of autologous micro-fragmented adipose tissue. Harris Hip Score improved from 67.2 ± 3.4 to 84.6 ± 6.3 and WOMAC from 36.3 ± 4.7 to 19.8 ± 3.4 at six months, with no adverse effects — in a retrospective series of six people with mild disease and no control group [22].
An earlier safety study injected autologous bone-marrow MSCs into 18 patients with knee, ankle or hip osteoarthritis. No severe adverse events occurred, there was no evidence of tumour formation over 30 months, and patients showed improvement in walking distance, VAS and WOMAC. The number of hip patients within that cohort was not reported separately [23].
How to read this
The direction is consistent: across every published hip series, patients improved and harms were minimal. That consistency is worth something, and it is why three separate review teams describe the approach as promising.
But consistency among small uncontrolled studies is exactly the pattern that larger controlled trials in this field have repeatedly deflated — and in the hip specifically, the one Level-1 network meta-analysis available found that no injection at all beat placebo [5]. In a joint where placebo injection performs as well as everything tested against it, uncontrolled improvement is not strong evidence of a drug effect.
The honest summary: plausible, consistently reported, and untested by the kind of trial that would settle it.
Umbilical cord as a cell source
Umbilical cord tissue requires no harvest procedure and yields cells with faster self-renewal than adult bone marrow [24]. Within the cord, Wharton's jelly is the most productive compartment, yielding 4.61 ± 0.57 × 10⁶ cells per centimetre without culture, with fewer non-stem-cell contaminants and greater chondrogenic potential than the amnion, subamnion or perivascular compartments [25].
Those are genuine advantages of the source. They are not evidence of clinical effect in the hip — no hip study has used umbilical cord MSCs. The hip series above used bone marrow or adipose tissue.
Osteonecrosis of the Femoral Head: A Different Condition, Better Evidence
Osteonecrosis — also called avascular necrosis — is not osteoarthritis. Blood supply to the femoral head is disrupted, bone dies, and if the head collapses the joint is destroyed, often in patients in their thirties to fifties. It is a distinct diagnosis requiring MRI, and it has its own treatment pathway.
It is also where cell therapy has its strongest evidence anywhere in the hip.
A systematic review and meta-analysis of randomised controlled trials — 13 trials, 619 patients, 855 hips with early-stage disease — found that stem cell therapy [6]:
These are randomised data, with hard clinical endpoints — collapse of the femoral head, and whether the patient needed a hip replacement — over long follow-up. A roughly two-thirds reduction in conversion to arthroplasty is a substantial result, and it should be stated as one.
Two qualifications. The treatment studied is generally cells delivered into the bone alongside core decompression, not an intra-articular injection — a different procedure from the one used for osteoarthritis. And the evidence applies to early-stage disease, before collapse.
On dose, a 2026 network meta-analysis of 18 studies and 1,192 patients found high-dose cells (>1 × 10⁸) with core decompression reduced conversion to arthroplasty versus core decompression alone (OR 0.24, 95% CI 0.12–0.44) and reduced collapse (OR 0.24, 0.08–0.74). But it found no significant advantage of high dose over low or medium dose, and no difference in adverse events between dose categories [26]. More cells outperformed no cells; more cells did not outperform fewer cells.
Hip Replacement: The Comparator, Accurately
Any discussion of alternatives has to represent the alternative fairly.
Durability. Pooled analysis of national joint registries covering 215,676 hip replacements found 25-year survival of 57.9% (95% CI 57.1–58.7). The authors' summary: patients can expect a hip replacement to last 25 years in around 58% of cases [7]. A population cohort of 63,158 hip replacements found 10-year implant survival of 95.6% and 20-year survival of 85.0% [8].
The commonly repeated claim that hip replacements "typically need revision within 15–20 years" is not what the registry data show.
Age changes this substantially. Lifetime risk of revision is about 5% for patients operated after age 70, rising to 35% (95% CI 30.9–39.1) for men having surgery in their early fifties, with women in the same age band at roughly 15% lower risk. For patients operated before 60, median time to revision was 4.4 years [8]. For a younger patient, that is a genuine argument for not rushing — though not, by itself, an argument for any particular alternative.
Complications. In a Medicare cohort of 58,521 primary hip replacements, the first six months brought 3.9% dislocation, 0.9% pulmonary embolism and 0.2% deep infection [27]. Linked registry and hospital data put 90-day periprosthetic joint infection after hip replacement at 1.1% (0.8–1.3), rising to 1.5% (1.3–1.7) under a broader case definition [28].
Activity. Modern hip replacement generally permits return to low-impact activity; recommendations on high-impact sport vary by surgeon, implant and patient, and are a matter for the operating surgeon rather than a general rule.
Where surgery is clearly right. Guidance is consistent that surgery should be reserved for patients who have not responded to less invasive approaches [10]— and equally, that for those patients it is highly effective.
Comparing the Options
No study has compared cell therapy against hip replacement, so the two cannot be placed in a head-to-head table. What can be said:
Hip replacement has decades of registry data on hundreds of thousands of patients, with quantified durability and quantified complication rates [7][8][27][28]. Its evidence base is among the strongest in orthopaedics.
Cell therapy for hip osteoarthritis has small uncontrolled series reporting consistent improvement and few harms [2][3][4], no randomised trial, and a Level-1 finding that no hip injection of any kind has beaten placebo [5].
Cell therapy for early osteonecrosis has randomised evidence that it delays collapse and reduces the need for hip replacement [6].
Those three statements are not interchangeable, and which one applies depends on the diagnosis.
What This Means for a Decision
If you have hip osteoarthritis, the evidence supports starting with what is best established: supervised exercise, education and weight management [9], with analgesia as needed and its risks understood [18]. Injection therapies have not outperformed placebo in the hip [5]. Cell therapy is investigational, is not in any current guideline [9], and its hip evidence is small and uncontrolled — a reasonable thing to consider with realistic expectations and full knowledge of that, not a substitute for the treatments that have been tested.
If you have osteonecrosis of the femoral head, the picture is different and better, particularly in early-stage disease before collapse [6]. This warrants a specific conversation with a hip surgeon, and an MRI if you have not had one.
If your hip is severely affected and conservative treatment has failed, replacement has strong evidence and good long-term durability [7][8], and delaying an operation you need has its own costs.
Questions worth asking any provider offering cell therapy for a hip: what is the diagnosis, osteoarthritis or osteonecrosis? What cell source and preparation, and what evidence exists for that specific product in the hip? What outcomes are measured, over what period, against what comparison? And what proportion of your hip patients go on to have a replacement anyway?
What Sterling-Certified Partner Clinics Offer
For transparency, separately from the evidence above: Sterling-certified partner clinics in Thailand provide allogeneic umbilical cord-derived MSC preparations under Thai FDA oversight, alongside supporting infusion services. Cell counts, session structure, viability specifications, pricing and adjunct services are commercial and clinical arrangements determined at the clinic. They are not findings from the literature and are not presented here as evidence of effect.
Adjunct offerings — including NAD+ infusion, NK/NKT cell preparations, plasmapheresis and cord blood plasma — have no published clinical evidence supporting their use for hip joint disease, and form no part of the evidence base described on this page.
Any treatment plan is a matter for a qualified physician who has examined you and reviewed your imaging.
Frequently Asked Questions
Does stem cell therapy work for hip arthritis?
It has not been tested in a randomised trial. Small uncontrolled series consistently report pain relief and functional improvement with few adverse events [2][3][4], but in the hip no injected treatment of any kind has outperformed placebo in randomised comparison [5]. That combination means the question is genuinely open, not settled either way.
Is the evidence the same as for knee arthritis?
No, and this is the most common misunderstanding. Knee osteoarthritis has meta-analyses of dozens of randomised trials. Hip osteoarthritis has 72 patients across seven uncontrolled studies in the largest bone-marrow MSC review [2]. Findings do not transfer between joints automatically.
Will it regrow my cartilage?
There is no evidence that it does in the hip. No hip study has demonstrated structural cartilage restoration against a control.
What about avascular necrosis — is that the same thing?
No. Osteonecrosis of the femoral head is a distinct condition, and it is the one hip diagnosis where cell therapy has randomised evidence — delaying collapse and reducing conversion to hip replacement by roughly two-thirds in early-stage disease [6]. If you have been told you have avascular necrosis rather than arthritis, that evidence is relevant to you and the arthritis evidence largely is not.
How long does a hip replacement last?
Longer than is often said. Pooled registry data give 57.9% survival at 25 years [7], with 20-year survival of 85% [8]. The main exception is younger patients: a man having hip replacement in his early fifties faces roughly a 35% lifetime risk of revision [8].
If I try cell therapy and it doesn't work, can I still have surgery?
Yes. Intra-articular injection does not alter joint anatomy or remove the option of later replacement. Whether it improves later surgical outcomes is a separate claim, and there is no controlled evidence for it.
Is it FDA-approved?
Not for orthopaedic conditions in the United States; it remains investigational for this indication in most jurisdictions. Sterling-certified partner clinics in Thailand operate under Thai FDA oversight, which is a different regulatory framework rather than an equivalent approval.
Related Reading
See also: Knee Pain & Osteoarthritis, Shoulder & Rotator Cuff, Elbow Tendinopathy, Wrist & Hand Conditions, Back Pain & Disc Disease.