If you’ve ruptured your Achilles tendon, you’ll almost certainly be given a walking boot. The two most common options are the Aircast and the VACOped. Both are effective — the research shows that what matters most is following your protocol, not which brand you’re wearing.
That said, the boots work differently, and understanding those differences can help you feel more confident about your recovery.
Contents
- Key Takeaways
- Why Your Boot Matters
- How They Work
- Quick Comparison
- What the Research Says
- Living With Your Boot
- Full Setup Costs
- What This Means for Your Recovery
- Frequently Asked Questions
- References
Key Takeaways
- Both boots produce excellent outcomes when used correctly — long-term results are similar
- The Aircast uses removable heel wedges; the VACOped uses an adjustable hinge
- The VACOped positions the ankle more accurately but costs roughly twice as much
- Most patients use whichever boot their hospital provides — and that’s fine
- Protocol compliance matters far more than boot choice
- Neither boot is comfortable to sleep in — a night splint helps
Why Your Boot Matters
Your boot has one job: hold your foot in a “toes-down” position (doctors call this equinus) so the torn tendon ends sit close together while they heal. If the tendon heals in a stretched-out position, your calf will be permanently weaker. Research suggests that up to 10mm of tendon lengthening is tolerable, but beyond that, you start losing power.
This is why the angle your boot holds matters. It’s also why you should never accelerate your wedge removal or angle changes — each step is designed to protect the tendon while it regains strength.
Over weeks 5–10, the angle is gradually reduced until your foot is flat. The two boots achieve this differently.
How They Work
Aircast (Wedge System)
The Aircast uses removable foam wedges stacked under your heel. You start with all wedges in (maximum angle), then remove them one at a time on your clinician’s schedule.
- Typical progression: 4 wedges (28°) → 3 wedges (22°) → 2 wedges (16°) → 1 wedge (10°) → flat
- Each removal drops the angle by roughly 6–8°
- Lightweight and widely available — the standard in most NHS hospitals
- Simple to adjust — just pull out a wedge
- Costs around £120–£150 ($150–$190)
- Not waterproof (you’ll need a waterproof cover for showering)
- Air-filled bladders provide customisable compression and help control swelling
The main concern with the Aircast is that research shows much of the “toes-down” bend happens through the midfoot rather than at the ankle joint itself. This means the tendon may not be in quite as protected a position as it appears from the outside.
VACOped (Hinge System)
The VACOped uses an adjustable hinge mechanism on the side of the boot, controlled by a dial. This allows precise angle changes and, later in recovery, controlled range of motion within a set range.
- Continuous adjustment from 30° to 0° plantarflexion — no step changes
- Later in recovery, the hinge unlocks to allow controlled ankle movement (e.g. 10–30° range)
- Vacuum-bead liner moulds to your leg shape for a snug fit
- Can be used in water (with the backup liner — fiddly but possible)
- Costs around £300 ($375)
- Heavier and bulkier than the Aircast — some patients also purchase an EVENup shoe leveler for the opposite foot
The VACOped’s hinge creates a true ankle bend, meaning the tendon position may be more accurate. Its dynamic range of motion later in recovery may also help reduce muscle wasting, though clinical evidence for this is still limited.
Quick Comparison
| Feature | Aircast | VACOped |
|---|---|---|
| How it works | Removable heel wedges | Adjustable hinge dial |
| Ankle positioning | 28° (via midfoot bend) | 48° (true ankle joint) |
| Approximate cost | £120–£150 | £300 |
| Weight | Lighter | Heavier |
| Waterproof | No (cover needed) | Yes (with modification) |
| Availability | Very common (NHS standard) | Less common, often self-funded |
| Ease of adjustment | Simple — remove a wedge | Easy — turn a dial |
| Range of motion | Fixed at each wedge level | Controlled ROM when unlocked |
| Sleeping | Uncomfortable | Uncomfortable |
What the Research Says
Ankle Positioning (Ellison et al., 2017)
A study comparing ankle angles in both boots using weight-bearing X-rays found significant differences:
| Boot | Ankle Angle (TTA) | Foot Angle (1MTA) | Notes |
|---|---|---|---|
| Traditional Cast | 56° | 74° | The gold standard position |
| VACOped | 48° | 54° | Close to cast positioning |
| Aircast with wedges | 28° | 37° | Much of the bend through the midfoot |
The VACOped achieved roughly 48° of true ankle plantarflexion — close to a traditional plaster cast (56°). The Aircast achieved about 28°, with much of the bend happening through the midfoot rather than at the ankle joint itself.
Long-Term Outcomes (UKSTAR Trial, 2020)
The large UKSTAR trial — the biggest randomised controlled trial on Achilles rupture management — found no significant difference in long-term outcomes between different boot types when patients followed their rehabilitation protocol. This is the strongest evidence we have, and it tells us that compliance matters more than which brand of boot you wear.
Tendon Loading (Baxter et al., 2022)
A biomechanical study measured how much force the Achilles tendon experiences while walking in different boots. On average, boots reduced tendon loading by 68% compared to normal walking. However, there were differences between designs — boots with a rigid posterior strut (like the VACOped) reduced loading by 77%, while wedge-based boots (like the Aircast) reduced it by 60–68%.
Functional Rehabilitation (Mampal et al., 2020)
A randomised controlled trial confirmed that functional rehabilitation with early weightbearing in a walking boot produces better early outcomes than traditional plaster cast treatment. This is why modern protocols encourage walking in a boot rather than immobilisation in a cast.
Real-World Protocol Outcomes
The SMART protocol (Swansea Morriston Achilles Rupture Treatment) — which uses the VACOped — reported a re-rupture rate of just 1.1% across 211 patients. The LAMP protocol (Leicester Achilles Management Protocol) achieved similar results with an ATRS functional score of 75.5 and a 2% re-rupture rate across 442 patients. Both demonstrate that well-managed non-operative treatment with either boot produces excellent outcomes.
Living With Your Boot
Walking
Both boots allow early weightbearing, but the experience differs. The Aircast is lighter, which some patients prefer. The VACOped’s thicker base can feel awkward initially, though its hinge may produce a more natural gait later in recovery as the range of motion is unlocked.
An EVENup shoe leveler on the opposite foot is worth considering with either boot — the height difference can cause back, hip, and knee pain over weeks of use.
Sleeping
Neither boot is designed for sleep, but 24/7 tendon protection is essential during the boot phase. Removing the boot overnight risks re-rupture if you accidentally pull your toes up in your sleep.
Most patients find sleeping in a heavy walking boot miserable — it’s hot, bulky, and disrupts sleep. A purpose-built night splint maintains the correct ankle angle while being far lighter and more comfortable. See our guide on sleeping with a torn Achilles for more tips.
Showering
The Aircast is not waterproof — you’ll need a waterproof boot cover like the Limbo, or you can sit on a stool and keep the boot out of the water.
The VACOped can technically go in water, but it requires removing the inner lining and using the backup liner. Patients describe this as fiddly but workable. Some find it useful for pool-based physiotherapy later in recovery.
Driving
If your right Achilles is ruptured, you cannot drive while in a boot. If the rupture is to your left Achilles, you may be able to drive an automatic car using your right foot — but check with your insurance provider and clinician first. See our full guide on driving during Achilles recovery.
Full Setup Costs
Beyond the boot itself, you’ll likely need a few extra items. Here’s what a complete setup costs:
Aircast Setup
| Item | UK (£) | US ($) |
|---|---|---|
| Aircast boot | 120 | 150 |
| Heel wedges | 20 | 25 |
| Waterproof cover | 23 | 30 |
| Night splint | 65 | 93 |
| Total | ~228 | ~298 |
VACOped Setup
| Item | UK (£) | US ($) |
|---|---|---|
| VACOped boot | 300 | 375 |
| Replacement liner (for swimming) | 31 | 40 |
| EVENup shoe leveler | 28 | 36 |
| Night splint | 65 | 93 |
| Total | ~424 | ~544 |
Prices are approximate and vary by retailer and region. Many NHS patients receive the Aircast free of charge.
What This Means for Your Recovery
Here’s the honest truth: most patients will use whatever boot their hospital provides, and that’s completely fine. Both boots protect the tendon effectively, and the UKSTAR trial shows long-term outcomes are similar.
If you’re choosing between them:
- Choose the Aircast if cost matters, your hospital provides it, or you want something lightweight and straightforward.
- Consider the VACOped if you can afford it, you want waterproofing for showering, or your clinician specifically recommends it.
Either way, focus on the things that actually drive your recovery:
- Follow your wedge/angle schedule exactly — never accelerate it
- Wear your boot (or night splint) 24/7 until told otherwise
- Start physiotherapy when your clinician advises — typically weeks 3–6
- Protect the tendon at night — a night splint makes nights far more bearable while keeping the tendon safe
Frequently Asked Questions
Can I switch from an Aircast to a VACOped mid-recovery?
Yes, but speak to your clinician first. They’ll need to set the correct angle on the new boot to match where you are in your protocol. Don’t try to do this yourself.
Is the VACOped worth the extra money?
It depends on your priorities. The ankle positioning may be more accurate, and the waterproofing is a genuine convenience. But the Aircast produces good outcomes too. If budget is tight, spend the difference on a night splint and good physiotherapy instead — those will have a bigger impact on your recovery.
Do I need to wear the boot at night?
Yes — tendon protection is essential 24/7 during the boot phase. Removing it overnight risks re-rupture if you accidentally dorsiflex (pull your toes up). Many patients find a purpose-built night splint far more comfortable than sleeping in a heavy boot. For more advice, see our guide on recovering from a torn Achilles.
When can I stop wearing the boot?
Most protocols transition out of the boot around weeks 10–12. This is based on clinical criteria — your clinician will assess tendon healing, range of motion, and strength before clearing you. The transition is gradual (a few hours without the boot each day, increasing over 1–2 weeks), not a sudden switch.
How do I prevent pressure sores from the boot?
Check your skin daily, especially around the ankle bones. The Aircast’s air bladders and the VACOped’s vacuum-bead liner are both designed to distribute pressure. Wear a thin, breathable sock (merino wool works well) and ensure the boot is properly fitted. If you notice redness or sore spots, contact your clinician.
Can I drive while wearing the boot?
If your right Achilles is ruptured, you cannot safely operate the pedals. If the rupture is to your left leg, you may be able to drive an automatic car — but always check with your insurance provider and clinician. The Aircast’s lighter weight is slightly less obstructive, but neither boot is designed for driving.
What else do I need besides the boot?
See our full guide on recovering from a torn Achilles. At minimum, you’ll likely need crutches, an EVENup shoe leveler for the other foot, a plan for sleeping (a night splint is recommended), and a waterproof solution for showering.
What are the signs of re-rupture?
A sudden pop or snap, a feeling of being kicked in the back of the leg, immediate difficulty walking, or the foot going flat when it shouldn’t. If you experience any of these, seek medical attention immediately. Re-rupture rates are low (3–5%) but the risk is highest when not following your protocol. Read more about preventing re-rupture.
References
- Ellison P, Molloy A, Mason LW. Early Protected Weightbearing for Acute Ruptures of the Achilles Tendon: Do Commonly Used Orthoses Produce the Required Equinus? J Foot Ankle Surg. 2017;56(5):960-963. PubMed
- Costa ML, et al. Plaster cast versus functional bracing for Achilles tendon rupture: the UKSTAR RCT. Health Technol Assess. 2020;24(8). PubMed
- Maempel JF, et al. A Randomized Controlled Trial Comparing Traditional Plaster Cast Rehabilitation With Functional Walking Boot Rehabilitation for Acute Achilles Tendon Ruptures. Am J Sports Med. 2020;48(11):2755-2764. PubMed
- Baxter JR, et al. Achilles Tendon Loading During Walking Differs Between Commonly Used Immobilizing Boots. Foot Ankle Orthop. 2022;7(4). PMC
- Valkering KP, et al. Functional weightbearing mobilization after Achilles tendon rupture enhances early healing response. Knee Surg Sports Traumatol Arthrosc. 2017;25(6):1807-1814. PubMed
- Hutchison AM, et al. The treatment of a rupture of the Achilles tendon using a dedicated management programme (SMART). Bone Joint J. 2015;97-B(4):510-515. PubMed
Primary source: Ellison P, Molloy A, Mason LW (2017). Early Protected Weightbearing for Acute Ruptures of the Achilles Tendon: Do Commonly Used Orthoses Produce the Required Equinus?
