What's a Bunion?

Giving your bunion space

Ill-fitting shoes have been seen to be associated with bunion formation and symptoms ^(4-6). That’s why our “HALF LENGTH SUPPORT FOOTBEDS” are a core feature to bunion relief.

It is offered in styles which contain our patented custom fit assembly. These footbeds provide the same level of arch support as our full length footbeds, however they provide the maximum amount possible of extra volume in the shoe to accommodate the bunion. This enables the shoe to be as slimline as possible.

Bunion only on one side? Wear the half length footbed on your affected side, and the full length footbed on your unaffected side. The custom fit assembly is perfect for women who have tricky to fit feet because of bunions.

Supporting your bunion

There is a known association between lowering of the medial arch and bunion formation ⁽⁷⁾.
Our footbeds have been purposely designed to support both the medial and transverse (forefoot) arch of the foot, making them the perfect option for women suffering from bunions.

We’ve strategically designed our footbeds to support the medial arch, cradle the heel and cushion the forefoot. Our transverse arch support follows the natural contour of the plantar surface of the foot, aiming to provide soft and comfortable relief as well as supporting the alignment of the foot.

Reducing the rub on your bunion

Most of our enclosed styles have a hidden soft foam lining in the forefoot area to minimise friction, pressure (and shear stress) over the skin around the forefoot. This is ideal for women with bunions as the joint often protrudes creating higher pressure of the joint on the upper ⁽⁹⁾.

Caroline McCulloch
Founder
B. Podiatry, B. Physiotherapy

Alan McCulloch
Founder
B. Podiatry, P.G.Dip in Human Movement Studies

Sara Taylor
Podiatrist
B. Podiatry (Hons)

Diagnosis of hallux valgus can usually be made with the patient standing barefoot by assessing the joint angle visually, and can be measured with a goniometer. More accurately though, the joint deformity can be measured by weight bearing x-ray views ⁽¹⁰⁾.

If the angle between the first toe and the first metatarsal exceeds 15 degrees, the angle of the joint is out of normal range. The metatarsals often look splayed and the first toe becomes rotated. Though not required for diagnosis, clinicians should also assess the mobility of the deformity and the position of the hindfoot to see if these are contributing factors ⁽¹⁰⁾.

Without x-ray or imaging, previous techniques for categorizing and monitoring hallux valgus development have included tracing around the foot, measuring the joint angle, measuring the girth of the foot, or taking photographs⁽¹¹⁾. The Manchester scale was developed by Garrow et.al.⁽¹²⁾ for a more uniform grading system. The Manchester Scale classifies hallux valgus using four clinical photographs:

No deformity: Grade 1

Mild deformity: Grade 2

Moderate deformity: Grade 3

Severe deformity: Grade 4

Click this link to view Manchester Scale images⁽¹³⁾.

In clinical practice Dr Sheree Hurn recommends describing hallux valgus as ‘mild, moderate, or severe’, using the Manchester Scale images as a reference, to enable clear communication between practitioners. She also recommends taking measurements from clinical photography if possible to track progression of hallux valgus ⁽¹¹⁾.

Genetics

Genetic inheritance has long been suspected. One study showed that 90% of 350 presenting cases had at least one relative also affected by hallux valgus ⁽¹⁷⁾, and another reported 68% of presenting cases showed a familial tendency ⁽¹⁸⁾. Hannan et al. confirmed the high heritability of hallux valgus in a large sample of 2,446 adults ⁽²⁾. One thing is for sure, it is in the genes!

Sex

The true sex ratio is unknown as it varies across population groups. The male to female ratio is 1:15 among those who have corrective surgery - however this may say more about who presents for surgery than actual occurrence ⁽¹⁹⁾. A systematic review found that the prevalence of hallux valgus was 2.3 times higher in women than men ⁽¹⁾. Studies agree that women are suffering from hallux valgus at a higher rate than men!

Ligamentous Laxity

Ligamentous laxity is an inherited collagen imbalance of the connective tissue. Hallux valgus occurs more commonly in people with ligamentous laxity. In saying this, conditions associated with ligamentous laxity – such as rheumatoid arthritis are often associated with increased incidence of hallux valgus ⁽¹⁴⁾.

Age

The peak onset of hallux valgus is seen between 30 and 60 years of age. However, this does not mean it is something to be ignored before then! Initial joint changes usually occur in adolescence ⁽¹⁴⁾.

Foot Type

Many anatomical features of the foot have been studied to investigate their association with hallux valgus. Some require x-rays and invasive tests while others are more visible clinically. Three easy things to look for that have been associated with hallux valgus include:

• Lowered medial longitudinal arch height – studies show those presenting with hallux valgus typically have a lowering of the first metatarsocuneiform joint visible on x-ray ^{(20, 21)}. Clinically it is easy to view the arch height and make judgement as to whether it is low, normal or high.
• Hypermobile first ray – there is a highly significant relationship between hypermobile first ray and hallux valgus at presentation ⁽²¹⁾.
• Long first ray - 80% of those studied had a first ray equal to or longer than second ⁽¹⁴⁾.

Muscle Strength

Research has shown that the intrinsic muscles of the foot are weakened in those with hallux valgus ⁽²²⁾. These stabilising muscles are important for balance and effective toe-off during walking. Due to insufficient research in this area, it is unclear whether muscle weakness is a cause of hallux valgus, or whether the weakness develops secondary to the poor alignment of the big toe.

Development

According to Perera et al. ⁽¹⁴⁾, hallux valgus usually develops slowly over time and he lists the deformity development usually occuring in the following order:

1. Failure of medial sesamoid and medial collateral ligaments of the first metatarsophalangeal joint.
2. Medial displacement of the first metatarsal.
3. Valgus rotation of the proximal phalanx.
4. Cartilage damage due to new position of medial sesamoid and lateral sesamoid appears to sit in intermetatarsal space.
5. Thickening of the bursa over the medial aspect of the joint – true ‘bunion’ appearance begins.
6. The extensor hallucis longus and flexor hallucis longus tendons appear to bowstring laterally, increasing the valgus displacement.
7. Metatarsal head drops off the sesamoids and pronates.
8. Abductor hallucis muscle becomes dysfunctional.
9. Dorsal joint capsule, no longer reinforced by tendons, is unstable.
10. Pressure can be transferred laterally due to first metatarsal displacement.
    
    For copy and image reference in this section (Parera et. al. 2011)

FRANKIE4 footwear designs have two goals when it comes to providing relief for women who suffer from hallux valgus;

1. Accommodation of the existing deformity
   
   
2. Redistribution of pressure under the foot

Accommodation of the existing deformity

Changing shoe brands or styles can often resolve symptoms associated with hallux valgus. Recommended shoe features are a wide toe box and a shoe upper that is made of pliable material such as soft leather ⁽⁹⁾.

Not all women want to wear shoes with a ‘wide toe box’ because they can look unfashionable, or ‘orthopedic’ in nature. To maintain a slimmer toe box profile, the use of our ‘half length footbeds’ enables the toe area of the shoe to have more volume without ‘looking chunky’ and compromising on style.

Further on our half length footbeds,  a study carried out by  Doty et al. ⁽²³⁾ recommended the use of  ¾ length orthoses for treatment of hallux valgus. Whilst different terminology, ‘¾ length’ is the same length as our half length support  footbeds. Their recommendation that if a clinician uses orthoses as a treatment option for hallux valgus, a ¾ length orthosis might be a better choice than a sulcus-or full length orthosis. Based on their findings, full length orthoses actually increased dorsal/medial in-shoe pressures in HV.

Now focusing on the upper to accommodate the hallux valgus. Our footwear styles that are suitable for hallux valgus sufferers have soft leather uppers and also feature a soft foam lining in the toe box area to further decrease pressure on their bunion.

Redistribution of pressure under the foot

Studies have shown that high pressures under the medial forefoot are associated with hallux valgus (8), and a clinical trial by Torkki et al. ⁽²⁴⁾ found significant pain relief with the use of foot orthoses in adults with hallux valgus. Experts recommend that supporting the medial longitudinal arch may improve symptoms, as well as preventing pronation of the forefoot, which accentuates valgus forces on the hallux ⁽⁹⁾.

The FRANKIE4 support footbed features a heel cradle and arch support contours - designed with the aim to support the wearer’s medial longitudinal arch.

Another arch we consider is the transverse arch to help redistribute pressure under the forefoot - our philosophy - soft smooth support to increase customer and patient comfort.

At FRANKIE4 we’ve designed our transverse arch support to follow the natural contour of the plantar foot surface and bias cushioning for comfort. The contour varies from our flat shoes to our high heels for comfort reasons, but as a whole there are no focused lumps under the foot like a fixed metatarsal dome. Research has shown that both plantar forefoot cushioning (similar to that of the FRANKIE4 footbed) and metatarsal domes alleviate forefoot pain. However, the dome padding was seen to be significantly more sensitive to placement than the forefoot cushion ⁽²⁵⁾. For this reason we avoid metatarsal domes with a ‘fixed built-in’ height, shape and location on our footbeds. Instead we opt for the use of a gentle plantar forefoot cushioning curve to support the transverse arch. What this means is that, if needed, a metatarsal dome, or metatarsal bar,  that is the most ideal shape and size can be added onto our footbeds in the correct location for that particular wearers foot. This can easily be done if needed by a Podiatrist, or Physiotherapist, or other person educated on placement and understanding of wearer comfort and pain relief.

To help demonstrate the FRANKIE4 transverse arch support in our removable footbeds; please refer to the cross section of our Support footbed in the graphic below. The highlighted orange line can give you a feel for how the FRANKIE4 footbed supports the transverse arch. We’ve strategically designed our footbeds to provide a soft, gentle transverse arch support; our goal is to reduce wearer symptoms, so comfort is critical. It is common for health professionals to prescribe a metatarsal dome when treating various forefoot conditions such as hallux valgus ^{(9, 10)}. We agree that this is a great treatment option when the metatarsal dome has been placed on the footbed in the location specific to the individual foots needs and comfort. The below outlines some important points regarding forefoot pads/domes;

Location of Dome or Pad

Current research supports the essential role of correct placement of the metatarsal dome. Many researchers believe that this is more important than design itself ^(25-27).

Generally speaking, this involves, whether it is placed centrally to lift the middle three metatarsals or shifted more medially or laterally for extra support of the 2nd metatarsal or 4th metatarsals respectively. How proximal or distal the dome (or other addition) sits on the footbed is dependent on individual patient/wearer needs on load shift and comfort tolerance. Prof Karl Landorf (Podiatry Professor, La Trobe University, Melbourne, Australia) is quoted in the online magazine Lower Extremity Review, saying, “The prescription of forefoot pads should depend on the condition being treated. For example, a patient with rheumatoid arthritis with widespread synovitis of the metatarsophalangeal joints may require different forefoot padding than someone with generalized metatarsalgia under the middle metatarsal heads.” ⁽²⁸⁾

Correct Type - Size/Shape/Hardness etc

The metatarsal dome design appears preferable to other pad designs based on the current literature, however the most effective shape or material density is unclear, as different studies have used a range of different materials. ^{(29, 30)}

How soft or hard the density of the dome is made of is often dependent on the patient’s weight, activity, foot type and tolerance/comfort. The height or elevation and general shape of the dome varies in accordance with the patient’s individual foot anatomy, comfort and of course is dictated by the goal of achieving pain relief.

The width/size of the dome is dependent on the width/size of the patient’s forefoot ⁽²⁹⁾. Clinical experience has shown us that a poorly fitting metatarsal domes may fail to alleviate painful symptoms and may cause foot discomfort. Whereas the correctly placed dome specific to the patients’ needs can be beneficial.

Ill-fitting domes may press into and load painful pressure points under the foot, rather than offload them and alleviate pain. However, further study is needed to investigate just how much of a role shape and material have on dome function ⁽²⁸⁾.

Ryan Robinson, former president of the Pedorthic Association of Canada, is quoted in the online magazine Lower Extremity Review, saying “You have to accept that you may need to adjust. Your modifications and adjustments are part of the game when dealing with met pads, and sometimes you need to rip them off and try something different for the best fit” ⁽²⁸⁾.

Everyone is unique and hence treatment of hallux valgus using metatarsal domes or any other insole/footbed/orthotic additions is better to be customised, or at least adjustable for the wearer, so that they can be re-adjusted until the correct location on the footbed is determined/felt.

We’ve considered this when designing our support footbeds. When used as part of a treatment plan, the FRANKIE4 footbeds are much like a pre-fabricated (off the shelf) soft orthotic, a great base for podiatrists and physiotherapists or other skilled people to add their own prescribed features upon (if needed). Our footbeds create a great supportive base, that will accommodate well a metatarsal dome the correct size, shape and location that can be placed as needed. When done this way, the metatarsal dome or any other shaped addition becomes fully customised for the wearers needs and risk of irritation or adverse results is reduced. It also means the dome can be removed if and when needed.