Definition and Epidemiology
Shin splints (shin splint syndrome), preferably called medial tibial stress syndrome, is characterized by insidious onset activity-related leg pain caused by overuse and resultant musculotendinous and periosteal inflammation. It is the most common cause of chronic leg pain in runners but it has also been reported in basketball, tennis, and volleyball.
The underlying pathology is believed to be tibial periostitis secondary to chronic excessive stress at the bone–muscle junction. Repeated forceful dorsiflexion of the foot, repeated impact loading during foot strike, and excessive high-velocity foot pronation can lead to microtears at the soft tissue attachments, especially soleus muscle, to the periosteum of tibia.1–3 This results in a musculotendinous inflammatory reaction. Poor shock absorption from shoes, hard running surface, rapid increase in the intensity of training, muscular weakness, and imbalances in strength of leg muscles, poor conditioning, and overweight are contributing factors.
Athletes present with leg pain following a recent increase in running volume and intensity. Initially, the pain is felt during running and often relieved with continued running. With progressive severity, pain tends to recur at the end of the run and then felt throughout running with impairment of running. Pain and tenderness are localized along the middle third of the posteromedial border of the tibia (Figure 29-1). There may be relative weakness of the tibialis posterior and flexor hallucis longus muscles compared to the uninjured leg.
Site of maximum pain and tenderness in medial tibial stress syndrome.
The differential diagnoses of exercise-related leg pain should include stress fracture of the tibia, exertional compartment syndrome, and other conditions (Tables 29-1 and 29-2).1–3 Differentiating features of chronic leg pain are summarized in Table 29-3. An algorithm characterizing the clinical features of common conditions causing lower leg pain based on history and examination is presented in Figure 29-2.1
Table 29-1. Causes of Chronic Leg Pain in Young Athletes |Favorite Table|Download (.pdf)
Table 29-1. Causes of Chronic Leg Pain in Young Athletes
Relatively More Common
Medial tibial stress syndrome
Chronic exertional compartment syndrome
Stress fractures of tibia or fibula
Relatively Less Common
Metabolic bone disease
Referred pain from spine, hip, or knee
Popliteal artery entrapment syndrome
Peripheral entrapment neuropathies (see Table 29-2)
Bone and muscle neoplasms
Table 29-2. Peripheral Nerve Entrapment in Leg |Favorite Table|Download (.pdf)
Table 29-2. Peripheral Nerve Entrapment in Leg
Site of Characteristic Pain
Site of Tingling Sensation on Tinel Test
Common peroneal nerve
Lateral leg and foot
From fibular neck with distal radiation
Superficial peroneal nerve