A BSI results from disruption of the homeostasis between microdamage formation and its removal. While most BSIs readily heal following a period of modified loading and a progressive return to running activities, the high recurrence rate of BSIs signals a need to address their underlying causative factors.
Bone stress injuries are a source of concern in long-distance runners, not only because of their frequency and the morbidity they cause but also because of their tendency to recur. A BSI occurs along a pathology continuum that begins with a stress reaction, which can progress to a stress fracture and, ultimately, a complete bone fracture. (2-4) The Talar Bump Test may help differentiate tibial stress fracture from MTSS.Bone stress injury (BSI) represents the inability of bone to withstand repetitive loading, which results in structural fatigue and localized bone pain and tenderness. (1) Single leg hopping is painful in about half of MTSS cases (and 70-100% of stress fractures). Applying a vibrating tuning fork over the tibia may help detect stress fracture with 75% sensitivity. More focal tenderness, the presence of anterior tibial tenderness, or any significant swelling suggests stress fracture. Tenderness from MTSS should involve at least 5 cm of the tibial border. Prolonged stress may generate a periosteal reaction detectable as a “rough” or “bumpy” feel upon palpation. Pain that persists more than five minutes post-activity carries a higher suspicion of stress fracture.Ĭlinical evaluation demonstrates diffuse tenderness over the posteromedial tibial border. Initially, symptoms may subside during training, but as the condition progresses (toward stress fracture), symptoms may linger throughout activity or even at rest. Symptoms are often worse with exertion – particularly at the beginning of a workout. The clinical presentation of MTSS includes vague, diffuse pain over the middle to distal posteromedial tibia.
Prolonged insult may lead to a tibial stress fracture, and many authors now believe that MTSS and stress fracture represent two different points along a continuum of bony stress reaction. Stress reactions occur when the normal adaptive remodeling response cannot keep pace with excessive training loads, i.e., high demands with inadequate recovery times. Healthy bone responds to this stress by remodeling itself more densely. The stress of exercise can temporarily weaken bone. Research suggests that traction periostitis may be an inflammatory precursor to a tibial stress fracture. While the relationship remains plausible, the available evidence is not supportive.” (5) The Bigger ProblemĮarly etiological theories focused on myofascial strain, but current evidence shows that a bony stress reaction is the most likely cause of MTSS. Is it Just Growing Pains?Ī systematic review of 56 studies on the relationship between adolescent growth and pain “generally indicated no association between maturation, growth and musculoskeletal conditions. Repetitive traction on the medial tibial crest results in myofascial strain, periosteal inflammation, and bony stress reaction. MTSS is believed to result from repetitive eccentric contraction of the deep flexors during running, jumping, or impact loading. The condition affects the vulnerable insertion points of the tibial fascia and deep ankle flexors along the medial tibial crest.