Stress Fracture

Populations and Risk Factors

Long-distance runners, dancers, gymnasts
Military recruits (repetitive marching/jumping — "march fracture" of the metatarsal)
Adolescents during rapid growth spurts
Older adults with osteoporosis or osteopenia
Female athletes with the Female Athlete Triad (disordered eating, amenorrhea, low bone density)
Individuals with biomechanical faults (overpronation, pes cavus)
Sudden increase in training volume or intensity (> 10% rule violation)

Cumulative overload: Repeated strenuous activity exceeds the bone's ability to remodel. Microdamage accumulates faster than osteoblasts can repair it
Muscle failure as contributing factor: Hypertonic or inflexible muscles fail as shock absorbers during impact loading, transferring greater stress to bone
Biomechanical factors: Overpronation, high arches (pes cavus), leg length discrepancy, and running surface hardness alter force distribution
Progression from periostitis: Chronic periosteal irritation can progress to cortical microfractures if the repetitive load continues
Metabolic contribution: Low bone density (osteoporosis, Female Athlete Triad) reduces the threshold for fracture under repetitive loading

Deep, aching, or boring pain initially intermittent, may become constant as the fracture progresses
Intense, sharp localized tenderness over the fracture site — focal point tenderness (unlike the diffuse tenderness of periostitis)
Pain worsened by weight-bearing and repetitive stress
Secondary muscle spasm around the site for protection
Pain with hopping on the affected limb (axial loading test)
Red flags: Intense localized bone pain unrelieved by muscle relaxation requires medical referral for imaging; persistent pain despite rest should not be attributed to "shin splints" without investigation

CMTO Appendix category A1 (MSK conditions)
Essential tests: point tenderness on bone, percussion test (sharp pain when tapping bone), Morton squeeze test (metatarsal stress fractures)
Key differentiator: muscle strains hurt with resisted testing. Stress fractures hurt with bone loading (axial compression, hopping, percussion)
Tuning fork test (128 Hz): focal pain at the fracture site when applied to the bone
Red flag: intense localized bone pain unrelieved by muscle relaxation requires imaging referral
Frequently misdiagnosed as medial tibial stress syndrome (shin splints)

Locally contraindicated near suspected or acute fracture site — do not compress, mobilize, or apply direct pressure over the bone
Address compensatory patterns: Muscle guarding, postural imbalances, and altered gait mechanics in areas away from the fracture
Once stable and diagnosed: Gentle myofascial release and light compressions proximal to the site. Treat secondary muscle spasms with care to avoid reducing necessary structural stabilization
Hydrotherapy: Avoid vigorous techniques. Gentle warm applications to surrounding muscles for pain relief
Biomechanical assessment: Address contributing factors (overpronation, muscle inflexibility) to prevent recurrence once healed
Do not dismiss persistent bone pain as "just shin splints" — refer for imaging

Stress fractures are microscopic bone fissures from cumulative mechanical overload. About 25% involve the tibia
Locally contraindicated near suspected or acute fracture sites. Address compensatory muscle guarding and postural imbalances elsewhere
Key differentiator: muscle strains hurt with resisted testing while stress fractures hurt with bone loading (axial compression, hopping, percussion)
Intense localized bone pain unrelieved by muscle relaxation is a red flag requiring medical referral for imaging
Frequently misdiagnosed as shin splints. Focal point tenderness and percussion sign help distinguish stress fracture from medial tibial stress syndrome
The Female Athlete Triad (disordered eating, amenorrhea, low bone density) is a significant risk factor