Definition

Functional hallux limitus occurs when the hallux range of motion is limited as a result of jamming of the 1st metatarsophalangeal joint.

Overview

Hallux limitus most commonly occurs when 1st ray plantarflexion is restricted during gait. Contributing factors to this condition are excessive force under the 1st ray, excessive heel eversion (subtalar joint pronation), or an everted forefoot. Over time, repetitive jamming can contribute to arthritis of the 1st metatarsophalangeal joint (structural hallux rigidus) or formation of a bunion deformity (hallux abducto valgus or HAV).

Clinical Goal for Orthotic Treatment

To decrease excessive ground reactive force under the first ray and to allow the first ray to plantarflex. The orthosis should be designed to decrease the everted position of the calcaneus when an everted rearfoot is present. In the case of an everted forefoot, the orthosis should support the lateral forefoot (forefoot valgus).

Prescription

To prescribe this device check “Hallux Limitus/HAV” under the Pathology Specific Orthoses section (Part A) of the prescription form.

Functional Hallux Limitus Prescription Recommendations

• Polypropylene Shell – semirigid
• Standard Heel Cup
  • A standard heel cup is generally sufficient. Consider changing this to a deep heel cup in the presence of an everted heel.
• Wide Width
  • The increased surface area under the arch with a wider width is more effective in preventing arch collapse and plantarflexing the first ray
• Minimum Cast Fill
  • An orthosis with minimum cast fill conforms to the arch, preventing arch collapse and plantarflexing the first ray
• Medial Heel Skive – 4mm
  • The medial heel skive increases force medial to the subtalar joint (STJ) axis to reduce excessive STJ pronation and heel eversion
• Inversion – 2 degrees
  • Inversion of the positive cast increases arch height under the base of the first metatarsal resulting in plantarflexion of the first metatarsal
• Rearfoot Post
  • The rearfoot post will help stabilize the orthosis in the shoe
• EVA Cover to Toes
  • The topcover allows the addition of the reverse Morton’s extension
• Reverse Morton’s Extension
  • A reverse Morton’s extension improves first ray plantarflexion

Summary

The orthosis for functional hallux limitus described is based on the literature (see references below). It promotes first ray plantarflexion, reduces compression in the 1st MTP joint, and improves hallux range of motion.

References

1. Boffeli TJ, Bean JK, Natwick JR. Biomechanical abnormalities and ulcers of the great toe in patients with diabetes. Foot Ankle Surg, 41(6):359-64, 2002.
2. Drago JJ, Oloff L, Jacobs AM. A comprehensive review of hallux limitus. J Foot Surg 23: 213, 1984.
3. Ebisui JM. The first ray axis and the first metatarsophalangeal joint; an anatomical and pathomechanical study. J Am Pod Med Assoc, 58:160-168, 1968.
4. Grady JF, Axe TM, Zager EJ, et al. A retrospective analysis of 772 patients with hallux limitus. J Am Podiatr Med Assoc 92:102, 2002.
5. Hetherington VJ, Johnson RE, Albritton JS. Necessary dorsiflexion of the first metatarsophalangeal joint during gait. J Foot Surg 29: 218, 1990.
6. Kashuk KB. Hallux rigidus, hallux limitus and other functionally limiting disorders of the great toe joint: background, treatment and case studies. J Foot Surg 14: 45, 1975.
7. Kelso SF, Richie DH Jr, Cohen IR, et al. Direction and range of motion of the first ray. J Am Podiatr Med Assoc, 72:600-605, 1982.
8. Laird PO. Functional hallux limitus. Illinois Podiatrists 9:4,1972.
9. Roukis TS, Landsman, AS. Hypermobility of the first ray: a critical review of the literature. J Foot Ankle Surg, 42: Nov/Dec 2003.
10. Roukis TS, Scherer PR, Anderson CF. Position of the first ray and motion of the first metatarsophalangeal joint. J Am Podiatr Med Assoc 86:538-546, 1996.
11. Scherer PR, Sanders J, Eldredge D, et al. Effect of functional foot orthoses on first metatarsophalangeal joint dorsiflexion in stance and gait, J Am Podiatr Med Assoc 96(6):474, 2006.
12. Shereff MJ. Pathology, anatomy and biomechanics of hallux valgus. Orthopaedics 13: 939, 1990.
13. Whitaker JM, Augustus K, Ishii S. Affect of low dye strap on pronation sensitive mechanical attributes of the foot. J Am Podiatr Med Assoc. 93:118, 2003.