Stress Fractures. (emphasis on Medial Tibial ). Stress Fracture-Scope of Disease. First described by Breithraupt in 1855 5 th metatarsal in marching Prussian soldiers (march fx ) Incidence around 10% of all musculoskeltal injuries (including military training)
(emphasis on Medial Tibial)
Usually takes at least 2-3 weeks to develop
Too Much Too Hard Too Soon (10% Rule)
Definitive Dx requires radiographic confirmation
Sensitivity % of pts w disease who test +
Specificity % of pts w/o disease who test -
(A) Endosteal remodeling and cortical thickening (arrow) consistent with a stress fracture.
(B) Sagittal high-resolution fast spin echo MRI of same patient
demonstrating moderate cortical thickening and a faint cortical fracture line (arrow).
phase 1 (flow phase)
phase 2 (blood-pool phase)
phase 3 (delayed phase)
Soft tissue injuries increased uptake in only phases 1 and 2
Shin splints have increased signal only in the delayed-phase images
Stress Fractures are + in all phases but take months to years to go to normal
Must correlate with symptoms
(A) Sagittal fast inversion recovery MRI of lateral ankle margin with bone marrow edema pattern in the fibula with periosteal reaction consistent with stress fracture.
(B) Sagittal fast spin echo MRI in the same patient demonstrates mild ill-defined
endosteum and periosteal new bone formation (arrow ).
Sagittal T2 fat saturation showing diffuse marrow edema.
Sagittalshowing diffuse marrow edema.
Ultrasound showing periosteal elevation and increased blood flow
Time to Heal
Arendt EA, Griffiths HJ. The use of MR imaging in the assessment and clinical management of stress reactions of bone in high-performance athletes. Clin Sports Med 1997;16:291–306
MTSSStress ReactionStress Fracture
Anterior Tibial Cortex
“Dreaded Black Line”
Stress Fx vs. Insufficiency Fx
Abnl Stress to Nl bone Nl stress to Abnl Bone
Cortical Fx vs. CancellousFx(consider DEXA if not good hx)
Long Bones Femoral Neck/Talus/Navicular
Low-grade fx at a low-risk site can be allowed to continue to compete
Low-grade fx at a high-risk site needs to heal before full return to activity
1st -4th Metatarsals