Nuss procedure vs vacuum bell: an honest comparison
Share
Neither is universally better; they treat different situations. The vacuum bell is a non-surgical option that works best in flexible, younger chests, while the Nuss procedure is the established surgical repair for severe, rigid or symptomatic cases. The honest comparison is about fit, timing and how reversible each choice is.
Key points
- Neither approach is a universal answer. The vacuum bell and the Nuss procedure treat different severities, chest flexibilities and ages, so the useful question is which fits a particular chest.
- Scaife and colleagues (2025, n=240) reported a successful vacuum bell outcome in 66% of patients, and a Swiss cohort at University Hospital Basel reported significant improvement in about 80% of 140; starting while the cartilage is still pliable and keeping daily use consistent are the two things that most influence the result.
- Cincinnati Children's Hospital reports the vacuum bell may remove the need for surgery in up to 35% of patients who use it, with the strongest results in children aged 6 to 12 who have a mild deformity.
- The Nuss procedure, described by Nuss and colleagues (1998), is the current surgical standard for adolescents; the support bar stays in place about two to three years and requires a second operation to remove it.
- Reported Nuss complications include bar displacement, pneumothorax and infection, and their number has risen as the operation has been adopted more widely (Haecker et al. 2024).
- Surgical repair commonly costs 40,000 to 70,000 dollars in the United States and is not reversible, while a vacuum bell trial costs a few hundred dollars and can be stopped at any time.
The short answer, expanded
The two options answer different questions. The vacuum bell is a silicone suction cup that lifts the sternum and the attached rib cartilage using negative pressure, worn daily over one to two years. It is conservative, reversible and cheap, and it works by sustained gentle remodelling, so it depends on a chest that is still flexible. The Nuss procedure is surgery: one or more curved metal bars are placed behind the sternum to hold it forward while the chest reshapes around them, then removed in a second operation two to three years later. It is definitive and works regardless of how rigid the chest is, but it is a major operation with real risks and a long recovery.
So the honest comparison is not which is better in the abstract. It is which fits a particular chest, at a particular age, with a particular severity. A flexible chest in a nine year old and a rigid, symptomatic chest in a twenty five year old are not the same decision. The rest of this article sets out what the evidence says about each option, who each suits, who each fails, and how the cost, time and reversibility differ, so the choice can be made on the facts rather than on whichever option a given clinic happens to offer.
What the evidence actually shows
The vacuum bell
The larger outcome cohorts are consistent with one another. A Swiss cohort at University Hospital Basel reported significant improvement in about 80% of 140 patients, Scaife and colleagues (2025, n=240) reported a successful outcome in 66%, and Haecker and colleagues (n=133) reported comparable results. These figures pool all patients together, including late starters and those who stopped inside two years. Two things separate the people who respond from the people who do not. Younger cartilage is more pliable, so adolescents typically respond faster and more completely than adults. And consistency of daily use over months, rather than weeks, is the dominant factor in the result.
The reported harms are minor. Zhou and colleagues (2024, n=65) recorded petechiae, small pinpoint spots of broken capillary, in 44.6% of children during use; all of them resolved after a short pause in treatment, with no permanent sequelae, and those who develop them rarely need to stop for long. Cincinnati Children's Hospital, which offers the therapy and sells no device, states it may remove the need for surgery in up to 35% of patients who use it, with the strongest results in children aged 6 to 12 who have a mild deformity. The modern protocol comes from an engineer who had pectus excavatum and corrected his own chest over roughly two and a half years; his cohort of about 450 patients aged 2 to 61 established a regimen of at least 30 minutes twice daily, extending to several hours (Haecker 2016), and sternal lift under the device has been confirmed thoracoscopically during surgery. Reviewing 20 years of use, Haecker and colleagues (2024) concluded the therapy is safe and a potential alternative to surgery in carefully selected patients, that under age 10 it appears a reasonable first step, and that no validated guidelines for it yet exist.
The Nuss procedure
The Nuss procedure, described by Nuss and colleagues (1998) after a 10-year experience, threads one or more curved metal bars behind the sternum to push it forward, and it is the current gold standard for surgical repair in adolescents. The bar stays in place about two to three years and then requires a second operation to remove it. Return to some sports is usually possible around three months after surgery, with a longer tail before full activity. It reshapes the chest mechanically and does not depend on cartilage flexibility, which is why it remains the realistic option for chests the vacuum bell cannot move.
It also carries real risk. Reported complications include bar displacement, pneumothorax, which is air trapped between the lung and the chest wall, and infection. Haecker and colleagues (2024) note that as the operation has been adopted more widely, the character and number of complications have increased, which is a reason to weigh the experience of the centre alongside everything else.
How severity is measured
Severity is usually graded with the Haller index, the chest width divided by its depth at the deepest point of the indentation. A typical chest without pectus excavatum sits near 2.5. Values below 3.2 are commonly called mild, 3.2 to 3.5 moderate, and above 3.5 severe, with 3.25 the long standing value at which surgical repair is typically considered. A related measure, the correction index, which St. Peter and colleagues showed separates affected from unaffected chests more cleanly, is increasingly reported alongside it. These numbers are how a clinician places a given chest on the mild-to-severe range that drives the choice between the two paths below.
The two paths side by side
| Monitoring | Vacuum bell | Nuss procedure | |
|---|---|---|---|
| Cost | Appointments only | A few hundred dollars | 40,000 to 70,000 dollars US, up to 100,000 uninsured |
| Time commitment | Annual review | 1 to 2 hours daily, 1 to 2 years | Days in hospital, months of recovery |
| Reversible | Yes | Yes, stop at any time | No |
| Second procedure | No | No | Yes, bar removal at 2 to 3 years |
| Best odds | Mild, asymptomatic | Age 11 or under, flexible chest | Severe, rigid or symptomatic |
| Closes other doors | Window narrows with age | No | Not applicable |
Who the vacuum bell works best for
The predictors are consistent enough to state directly. The strongest single candidate is a child aged 11 or younger with a flexible chest that visibly lifts under suction, because cartilage that has not begun to ossify responds to sustained deformation, and age is the dominant influence on the result. Shallow to moderate depth helps, as does a realistic expectation measured in years rather than months. Adolescents and adults with a flexible chest wall remain reasonable candidates with longer timelines; the pioneer cohort included patients up to 61 (Haecker 2016). Conservative treatment is a formally accepted first step in mild-to-moderate deformity and in patients too young for surgery (Loufopoulos et al. 2021). For these groups a time-limited trial costs little and forecloses nothing.
When surgery is the right answer
Surgery is the honest recommendation for a recognisable group, and pretending otherwise would be a disservice. It is the appropriate route at the severe end of the scale, meaning a Haller value above 3.5 or a chest at or beyond the long standing 3.25 threshold, particularly when the chest is rigid and no longer flexes. It is the right answer when the deformity is symptomatic, meaning the chest wall compresses the heart or lungs enough to cause exercise intolerance, breathlessness or documented cardiopulmonary effects, because there surgery addresses a functional problem rather than an appearance. It is usually the realistic option for adults with a deep, long standing, ossified chest, which is a poor target for gradual remodelling. And it is the reasonable next step when a fair conservative trial has run its course without meaningful change. In each of these situations the Nuss procedure is not a fallback; it is the intervention the evidence points toward.
Who this does not work for
The vacuum bell does not work for a rigid chest wall that does not visibly lift under suction; the mechanical precondition is simply absent, and time will not change that. It does not work for a deep, long standing, ossified chest in an adult, which is usually a surgical conversation. It does not work for anyone who cannot commit to daily use across one to two years, which is the single largest failure group and not a character judgement. It is not for pectus carinatum, the opposite deformity, which needs compression rather than suction. And it is not for people with cardiac conditions, bleeding disorders, vasculopathies or active skin disease over the area without clinical clearance first. Surgery, in turn, is not the right first move for a mild, asymptomatic chest in a young child, where a conservative trial or watchful monitoring carries a far smaller downside, and where an operation done too early can need revising as the chest grows. Anyone with unexplained breathlessness, palpitations, chest pain or reduced exercise tolerance should be assessed by a physician before choosing either path.
What this means in practice
Three things follow. First, in a child under 11, age is the variable you cannot get back: costal cartilage stiffens through adolescence, and the odds available now are better than the odds available in two years. Second, consistency is the variable you can control, and it is the one that fails most often; Haje and colleagues (2021, n=115) found structured support raised adherence from 58% to 83%. Third, a vacuum bell trial is a trial, not a commitment: six months of consistent use is usually enough to know whether a chest is responding, and if it is not, surgery remains available. Conservative treatment does not close the surgical door, whereas surgery is not reversible.
The cost asymmetry is part of the decision
Surgical repair in the United States commonly runs 40,000 to 70,000 dollars, with uninsured cases reported up to 100,000, and costs are materially lower in Europe. It involves a bar in the chest for two to three years and a second operation to remove it. A vacuum bell, by contrast, costs a few hundred dollars and can be stopped at any time, and some insurers have covered it in full or in part as durable medical equipment. That asymmetry does not make conservative treatment the right answer. For a severe, rigid or symptomatic chest, surgery is often the right one. It does mean that for a flexible chest in a young patient, a time-limited trial carries a very different downside to a surgical decision, and that difference is a legitimate input rather than a marketing point.
Not sure whether this applies to you?
The question this article cannot answer for you is whether your own chest is a reasonable candidate for conservative treatment. The FormaChest assessment takes about four minutes. It screens your situation against the variables the research identifies as predictive (age, depth of the indentation, chest flexibility and symptoms) and returns an honest read on whether conservative treatment is a reasonable first step, including telling you when the answer is to see a surgeon first.
What the research does not tell us
Presenting either option as settled would misrepresent the evidence. There are no randomised controlled trials of the vacuum bell against surgery, against a sham device, or against no treatment; every vacuum bell study cited here is retrospective, observational or survey based. There are no validated international guidelines for the therapy, so daily duration, session length and total treatment time vary between centres, which is part of why reported figures disagree. Long term durability data past 15 years is thin, so whether a correction achieved in childhood holds through adult growth is not well established. Outcome measures differ between studies, some using the Haller index and some external depth, which is why headline figures from different papers should not be compared directly. On the surgical side, the literature reports complications more consistently than it reports long term quality of life, and the way complication patterns shift as the operation spreads to more centres is still being characterised. None of this tells you what your own chest will do, which is why an individual assessment matters more than any pooled number.
About this guide Published by FormaChest (AUGUMENTUM SRL, Romania). We manufacture non-surgical vacuum bell correction systems and sell nothing related to the procedure described above. This article exists because the decision described here should be made on the evidence, including the evidence that points toward surgery.Tomas Titus is the founder of FormaChest (AUGUMENTUM SRL, Craiova, Romania). He had pectus excavatum and corrected it without surgery, documenting his own vacuum bell treatment on camera, taking each measurement before a session rather than after. His chest depth went from 25mm to 4mm. That is one person's result at 19; published adult timelines run 12 to 24 months and results vary. He is not a clinician and has no financial interest in surgical care, and nothing in this article is a substitute for assessment by a qualified physician.Related questions
- What is pectus excavatum?
- How much does the Nuss procedure cost?
- Does the vacuum bell actually work?
- What are the non-surgical treatment options?
References
- Scaife ER, et al. Vacuum bell therapy for pectus excavatum. 2025. n=240
- Nuss D, Kelly RE Jr, Croitoru DP, Katz ME. A 10-year review of a minimally invasive technique for the correction of pectus excavatum. Journal of Pediatric Surgery. 1998.
- Haecker FM. Vacuum bell therapy. Annals of Cardiothoracic Surgery. 2016;5(5):440-449. PMID 27747177
- Haecker FM, et al. 20 years clinical application of the vacuum bell for conservative treatment of pectus excavatum. Journal of Thoracic Disease. 2024;16(8):5285-5298. PMID 39268139
- Loufopoulos I, Karagiannidis IG, Lampridis S, Mitsos S, Panagiotopoulos N. Vacuum Bell: Is It a Useful Innovative Device for Pectus Excavatum Correction? Turkish Thoracic Journal. 2021;22(3):251-256. PMID 35110237
- St. Peter SD, et al. A novel measure for pectus excavatum: the correction index. Annals of Thoracic Surgery.
- Cincinnati Children's Hospital Medical Center. Pectus excavatum: surgical and non-surgical care. Patient education resource.
This article is for information only and is not medical advice. Pectus excavatum should be diagnosed and assessed by a qualified physician, and any decision about surgery should be made with a surgeon who has examined you. If you have chest pain, breathlessness, palpitations or reduced exercise tolerance, seek medical assessment before choosing any treatment.
Last reviewed: July 2026.