Hamstring Muscle Injuries

What are the other Names for this Condition? (Also known as/Synonyms)

• Hamstring Muscle Strain
• Hamstring Tear
• Muscle Strain Injury of the Thigh

What is Hamstring Muscle Injuries? (Definition/Background Information)

• The hamstrings are a group of three muscles that run down the back of the thigh. The three hamstring muscles are semitendinosus, semimembranosus, and biceps femoris
• A Hamstring Muscle Injury, such as a Pulled Hamstring, is an injury characterized by the partial tearing or sudden stretching of one or more of these muscle fibers located along the back of the thigh
• These injuries are very common in sportspersons or athletes who participate in sports such as basketball, football, and tennis. The risk of an injury to the hamstring is also common in sports that require a lot of running, such as with track and field events and athletics
• Individuals that return too quickly from a Hamstring Injury before it had a chance to heal may cause the injury to recur
• The appropriate treatment for Hamstring Muscle Injuries does not usually involve surgery. However, surgery may be required if the hamstring is pulled completely off the bone. The prognosis for a majority of such injuries is usually excellent

Depending on the severity of the injury, physicians usually classify Hamstring Muscle Injuries into three different grades. These grades include:

• Grade I Hamstring Muscle Injury: Grade I occurs when only a small number of muscle fibers have been stretched or torn
• Grade II Hamstring Muscle Injury: Grade II occurs when a larger number of muscle fibers have been stretched or torn, resulting in immediate pain, decreased strength, and occasional bruising
• Grade III Hamstring Muscle Injury: Grade III is a complete rupture of the muscle fibers within the thigh

Who gets Hamstring Muscle Injuries? (Age and Sex Distribution)

• Individuals of any age, gender, race, or ethnic group may experience a Hamstring Muscle Strain
• However, this injury predominately occurs in athletes who participate in sports that require a lot of running

What are the Risk Factors for Hamstring Muscle Injuries? (Predisposing Factors)

Common risk factors associated with a Hamstring Muscle Injury include:

• Individuals who participate in sports, such as football, basketball, tennis, and athletics, that put stress on the hamstring
• A previous injury to the thigh muscles
• Tightness of the hamstring muscle
• Muscle weakness due to poor conditioning
• Tired muscles

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others. 

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider. 

What are the Causes of Hamstring Muscle Injuries? (Etiology)

Hamstring Muscle Strains occur when the muscles stretch beyond their capacity. Some of the causes of may include:

• Participation in sports such as football, basketball, tennis, and athletics
• Muscle imbalance, muscular fatigue, and weakness
• Any significant traumatic event such as an automobile accident
• Cold weather, which decreases flexibility of the thigh muscle fibers
• Overexertion of the thigh muscles beyond its capability such as with gymnastics or certain stretching exercises

What are the Signs and Symptoms of Hamstring Muscle Injuries?

The pain one experiences with a Hamstring Muscle Strain Injury and depends on the severity of the injury. The common signs and symptoms may include:

• Severe pain in the back of the thigh
• Weakness in the hamstring
• Noticeable bruising in the back of the leg
• Difficulty walking
• Difficulty bending the knee
• Muscle stiffness, muscular spasms
• Decreased range of motion of the thigh

How is Hamstring Muscle Injuries Diagnosed?

Physicians may use the following tools to diagnose a Hamstring Muscle Injury:

• Physical examination: Hamstring Muscle Injury can usually be diagnosed by a thorough physical examination. In addition to this, a complete medical history can aid in arriving at a definitive diagnosis
• X-ray of the thigh: An X-ray of the thigh is a common method used to evaluate a hamstring injury. This diagnostic test provides a clear image of the thigh, may help confirm the diagnosis, and determine the extent of the injury. The thigh x-ray may also be necessary if a possible fracture or other injuries to the thigh has occurred
• Magnetic resonance imaging (MRI) of the thigh: An MRI is a more detailed scan that uses a magnetic field to produce images. MRIs allow physicians to view any damage to the bones and soft tissue to confirm the diagnosis

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Hamstring Muscle Injuries?

Complications of Hamstring Muscle Injuries include:

• Prolonged and chronic pain within the thigh
• Recurrence of the injury

How is Hamstring Muscle Injuries Treated?

Conservative, nonsurgical methods usually form the first line of treatment for Hamstring Muscle Injuries. The RICE method is effective for a high percentage of sports-related injuries. RICE is an acronym for Rest, Ice, Compression, and Elevation.

• Rest: Any activity that aggravates the leg condition should be avoided. The physician usually advises the individuals to refrain from such activities, until the symptoms get better
• Ice: Applying ice to the back of the leg may help decrease pain and reduce swelling
• Compression: Wearing an elastic compression bandage can help stop additional swelling and loss of blood
• Elevation: Elevating the hamstring helps to decrease swelling
• Non-steroidal anti-inflammatory medication, such as ibuprofen and naproxen, can help to decrease the pain in the thigh
• Physical therapy: After the signs and symptoms have decreased, it is important to begin some light motion exercises. Physical therapy may help restore strength, as well as flexibility in the muscles

Surgery for a Hamstring Muscle Injury is usually performed when a tendon is pulled completely off the bone (avulsion fracture). During this procedure, a physician will pull the hamstring muscle back into its correct position and remove any scar tissue. 

How can Hamstring Muscle Injuries be Prevented?

A few recommendations to help prevent Hamstring Muscle Injuries include:

• Warming-up prior to exercising
• Correct stretching techniques are recommended before and after an athletic event
• Individuals who participate in any high-impact sports, such as football or hockey, should wear appropriate safety equipment to help prevent the possibility of a Hamstring Muscle Injury
• Wearing appropriate footwear (such as the proper shoe size) may help prevent accidents

What is the Prognosis of Hamstring Muscle Injuries? (Outcomes/Resolutions)

• The long-term prognosis of Hamstring Muscle Injuries is usually good in a majority of the individuals. When properly treated, a high percentage of individuals regain their full strength and range of motion in the affected thigh
• Mild to moderate Hamstring Muscle Injuries usually heal within 6 weeks. With a complete hamstring rupture, surgery may be recommended followed by very intensive physical therapy. A full recovery may take at least six months
• Individuals who re-injure the hamstring have an increased risk of permanent damage, which may result in a chronic condition

Additional and Relevant Useful Information for Hamstring Muscle Injuries:

The following DoveMed website link is a useful resource for additional information:

https://www.dovemed.com/health-topics/orthopedc-disorders/