Case Presentation: 41 Year Old Female with Medial Foot Pain

 Case Presentation-41 Year Old Female with Medial Foot Pain

Cliff Tao DC, DACBR

Published:

Journal of the Academy of Chiropractic Orthopedists

December 2016, Volume 13, Issue 2

This article is available from: http://www.dcorthoacademy.com © 2016 Tao and the Academy of Chiropractic Orthopedists. This is an Open Access article which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

A 41 year old female recreational runner complains of left medial foot pain. There is bilateral prominence at the medial aspect of the navicular tarsal on visual inspection, with tenderness and some redness on the left side. Bilateral foot radiographs are taken and the pertinent images are shown in Figure 1. What is your diagnosis?

C:\Users\costco\Downloads\Fig 1 tao dec16.png

.

Figure 1: Bilateral dorsoplantar radiograph of the feet

Diagnosis

Type 2 accessory navicular bone of the left foot, type 3 accessory navicular of the right foot.

Discussion

Accessory navicular bones are the most common accessory bone in the foot, occurring in up to about 20% of the population, and are frequently bilateral. Of the 3 types commonly known and outlined in Table 1, type 2 is associated most frequently with symptoms. The type 2 accessory navicular is formed from an accessory ossification center, which usually ossifies at about 9 to 11 years of age. These are usually triangular in shape and are at least partially united to the navicular by a synchondrosis with hyaline and/or fibrocartilage.

Type 1

C:\Users\cliff\Desktop\JACO Dec 2016\accessory_navicular_bone_variants.jpg

  • Os tibiale externum
  • Usually asymptomatic
  • Sesamoid bone within posterior tibial tendon
  • 30% of accessory navicular bones

Type 2

C:\Users\cliff\Desktop\JACO Dec 2016\accessory_navicular_bone_variants.jpg

  • 55% of accessory navicular bones
  • Most commonly symptomatic
  • Triangular shaped
  • Synchondrosis

Type 3

C:\Users\cliff\Desktop\JACO Dec 2016\accessory_navicular_bone_variants.jpg

  • Cornuate or gorilliform navicular
  • Prominent navicular tuberosity
  • May be symptomatic due to bunion formation

Table 1: Types and characteristics of accessory navicular bones.

Symptomatic patients frequently have posterior tibial tendon dysfunction, especially in middle-aged or older patients. Children or early adults with navicular pain from a type 2 accessory navicular bone usually do not have tendon abnormality.

Magnetic resonance imaging (MRI) is generally indicated to evaluate for extent of injury and plan treatment, and to rule out other sources of pain such as posterior tibial tendinopathy, osteonecrosis, or fracture. Marrow edema, greater in the accessory bone than in the navicular tarsal bone is the hallmark finding (Figure 2). Severity of injury increases with synchondrosis fluid, and with widening of the synchondrosis. Ultrasound is also a useful imaging tool, but only in the skilled operator. Computed tomography (CT) does not offer much benefit over plain radiographs due to limited soft tissue evaluation.

C:\Users\costco\Downloads\Fig 2 tao dec16.png
Figure 2: T1 axial (left), short arrow showing type 2 accessory navicular bone, and fat-suppressed T2 axial (right), long arrow showing marrow edema in the accessory bone (different patient than in Figure 1).

Treatment begins conservatively, ranging from just activity modification, to non-weightbearing cast immobilization. Secondary conservative treatment should include chiropractic adjustments and/or manipulations, dietary changes, and pain relief with physiotherapy modalities and/ or medications. Failure of conservative treatment is an indication for surgery, where the ossicle is excised, commonly via the Kidner procedure.

References

Choi YS et al. MR imaging findings of painful type II accessory navicular bone: correlation with surgical and pathologic studies, Korean J Radiol 5(4): 274-9, 2004.

Tuthill HL et al. Imaging of tarsal navicular disorders: a pictorial review. Foot Ankle Spec 7(3): 211-25, 2014.

 Case Presentation-41 Year Old Female with Medial Foot Pain

Cliff Tao DC, DACBR

Published:

Journal of the Academy of Chiropractic Orthopedists

December 2016, Volume 13, Issue 2

This article is available from: http://www.dcorthoacademy.com © 2016 Tao and the Academy of Chiropractic Orthopedists. This is an Open Access article which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

A 41 year old female recreational runner complains of left medial foot pain. There is bilateral prominence at the medial aspect of the navicular tarsal on visual inspection, with tenderness and some redness on the left side. Bilateral foot radiographs are taken and the pertinent images are shown in Figure 1. What is your diagnosis?

C:\Users\costco\Downloads\Fig 1 tao dec16.png

.

Figure 1: Bilateral dorsoplantar radiograph of the feet

Diagnosis

Type 2 accessory navicular bone of the left foot, type 3 accessory navicular of the right foot.

Discussion

Accessory navicular bones are the most common accessory bone in the foot, occurring in up to about 20% of the population, and are frequently bilateral. Of the 3 types commonly known and outlined in Table 1, type 2 is associated most frequently with symptoms. The type 2 accessory navicular is formed from an accessory ossification center, which usually ossifies at about 9 to 11 years of age. These are usually triangular in shape and are at least partially united to the navicular by a synchondrosis with hyaline and/or fibrocartilage.

Type 1

C:\Users\cliff\Desktop\JACO Dec 2016\accessory_navicular_bone_variants.jpg

  • Os tibiale externum
  • Usually asymptomatic
  • Sesamoid bone within posterior tibial tendon
  • 30% of accessory navicular bones

Type 2

C:\Users\cliff\Desktop\JACO Dec 2016\accessory_navicular_bone_variants.jpg

  • 55% of accessory navicular bones
  • Most commonly symptomatic
  • Triangular shaped
  • Synchondrosis

Type 3

C:\Users\cliff\Desktop\JACO Dec 2016\accessory_navicular_bone_variants.jpg

  • Cornuate or gorilliform navicular
  • Prominent navicular tuberosity
  • May be symptomatic due to bunion formation

Table 1: Types and characteristics of accessory navicular bones.

Symptomatic patients frequently have posterior tibial tendon dysfunction, especially in middle-aged or older patients. Children or early adults with navicular pain from a type 2 accessory navicular bone usually do not have tendon abnormality.

Magnetic resonance imaging (MRI) is generally indicated to evaluate for extent of injury and plan treatment, and to rule out other sources of pain such as posterior tibial tendinopathy, osteonecrosis, or fracture. Marrow edema, greater in the accessory bone than in the navicular tarsal bone is the hallmark finding (Figure 2). Severity of injury increases with synchondrosis fluid, and with widening of the synchondrosis. Ultrasound is also a useful imaging tool, but only in the skilled operator. Computed tomography (CT) does not offer much benefit over plain radiographs due to limited soft tissue evaluation.

C:\Users\costco\Downloads\Fig 2 tao dec16.png
Figure 2: T1 axial (left), short arrow showing type 2 accessory navicular bone, and fat-suppressed T2 axial (right), long arrow showing marrow edema in the accessory bone (different patient than in Figure 1).

Treatment begins conservatively, ranging from just activity modification, to non-weightbearing cast immobilization. Secondary conservative treatment should include chiropractic adjustments and/or manipulations, dietary changes, and pain relief with physiotherapy modalities and/ or medications. Failure of conservative treatment is an indication for surgery, where the ossicle is excised, commonly via the Kidner procedure.

References

Choi YS et al. MR imaging findings of painful type II accessory navicular bone: correlation with surgical and pathologic studies, Korean J Radiol 5(4): 274-9, 2004.

Tuthill HL et al. Imaging of tarsal navicular disorders: a pictorial review. Foot Ankle Spec 7(3): 211-25, 2014.