Straining of the hamstring, also known as a pulled hamstring, is defined as an excessive stretch or tear of muscle fibers and related tissues. Hamstring injuries are common in athletes participating in many sports. Track and field athletes are particularly at risk, as hamstring injuries have been estimated to make up 29% of all injuries in sprinters. Hamstring injuries can also come with a hip injury from sprinting. Symptoms for a hip injury are pain, aching and discomfort while running or any physical exercise. The biceps femoris long head is at the most risk for injury, possibly due to its reduced moment of knee and hip flexion as compared to the medial hamstrings. Causes of hamstring strain
The muscle group is prone to injuries due to the explosive nature of movement in sports and thus causing overload and overstretching of the hamstring musculature. The other causes may be:

Previous injury
Poor muscle strength
Poor flexibility
Inadequate warm-up
Fatigue
Imbalance
OveruseThis condition is most commonly seen in:

Athletes involved in soccer, baseball, football, rugby
Dancers and water skiers
Sports involving cross-country skiing, downhill skiing, judo, cricket, and bull riding

Diagnosis
Grades
Grade 1
Sensation of cramp or tightness and a slight feeling of pain when the muscles are stretched or contracted. Grade 2
With a grade two hamstring strain there is immediate pain which is more severe than the pain of a grade one injury. It is confirmed by pain on stretch, swelling and contraction of the muscle. Grade 3
A grade three hamstring strain is a severe injury.
Diroximel fumarate, sold under the brand name Vumerity, is a medication used for the treatment of relapsing forms of multiple sclerosis (MS). It acts as an immunosuppressant and anti-inflammatory drug. Its most common adverse effects are flushing and gastrointestinal problems.Diroximel fumarate was approved for medical use in the United States in October 2019, and in the European Union in November 2021. Medical uses
Diroximel fumarate is used for the treatment of relapsing-remitting multiple sclerosis. In the US, it is additionally approved for other relapsing forms of MS such as clinically isolated syndrome and active secondary progressive disease. Available forms
The drug is available as a white delayed-release capsule that is resistant to gastric acid and only dissolves in the intestine. Contraindications
Under the European Unions label, the drug is contraindicated in people with progressive multifocal leukoencephalopathy (PML), a disease of the brain caused by a virus. In the US, combination with the closely related drug dimethyl fumarate is contraindicated. Side effects
No systematic studies of adverse effects under diroximel fumarate are available. The most common side effects in studies with dimethyl fumarate were flushing (in 34% of patients treated with the drug, versus 5% in the placebo group) and gastrointestinal effects such as diarrhoea (14% versus 10%), nausea (12% versus 9%), abdominal pain (9% versus 4%), vomiting (8% versus 5%), and indigestion (5% versus 3%). Three percent of patients stopped the treatment because of flushing, 4% because of gastrointestinal side effects.