Hamstring Strain

What is Hamstring Strain?

A hamstring strain is a common injury affecting the muscles at the back of the thigh, which are responsible for bending the knee and extending the hip. This type of strain occurs when these muscles are overstretched or subjected to excessive force, often during activities that involve sprinting, jumping, or sudden changes in direction.

• Mild hamstring strains might have little pain and a quick healing period. Alternatively, they may require weeks on crutches and surgery due to their severity.
• You may bend your knee and extend your hip by using the biceps femoris, semitendinosus, and semimembranosus, three muscles that go down the back of your leg from your thigh to your knee. The phrase “hamstring” refers to all of them combined.

What Are the Symptoms of a Hamstring Strain?

• If you strain your hamstring while jogging, you probably won’t notice it right away. There will be a sudden, intense pain and maybe a popping feeling at the back of your leg. You might stumble and lose the ability to run.

Additional signs of a pulled hamstring include:

• discomfort when bending or straightening your legs near the back of your thigh.
• back pain, bruising, and thigh edema.
• a prolonged period of weakness in your leg following the injury.

What Causes a Hamstring Strain?

• Muscle overload, like when you’re jogging and your leg is completely extended right before your foot hits the ground, is usually the cause of a hamstring strain. The muscles may get overstretched and tear when your foot hits the ground while standing on it.
• People who participate in sprinting or jumping-intensive activities such as track and field, soccer, football, lacrosse, basketball, and dance are more likely to develop hamstring strains. These kinds of injuries are also more likely in teens who are going through growth spurts. This is because a person’s muscles may develop taut and more prone to overstretching when their leg bones grow more quickly than their muscles.

• Here is a summary of some of the most common reasons why people get hamstring strains.

• not fully warming up before working out.
• being overweight or going overboard. Muscles that are weaker are less able to endure the strain of exercise, and muscles that are tired are less able to absorb energy, both of which raise the risk of injury.
• An imbalance in the muscle mass of your legs. Quadriceps, or front-leg muscles, are often bigger and stronger than hamstrings. The hamstring muscles are more prone to straining during running-related activities because they can tire out faster than the quadriceps.
• Ineffective method. Your hamstring muscles may experience more strain if you run with poor form.
  you are taking up activities too soon after being hurt. To completely recover from hamstring issues, a lot of rest and patience are required. You risk reinjuring your hamstring if you attempt to recover from a strain too quickly.

Risk Factors of Hamstring Strain:

• Older age
• Previous hamstring injury
• Limited hamstring flexibility
• Increased fatigue
• Poor core stability
• Strength imbalance
• Ethnicity
• Previous calf injury
• Previous substantial knee injury
• Osteitis pubis
• The incidence of hamstring strains among amateur Australian Rules football players was found to be negatively linked with better quadriceps flexibility.

• Participation in particular preventive programs is recommended for players who exhibit specific polymorphisms, such as IGF2 and CCL2 (especially in its allelic form GG), as they may be more susceptible to serious injuries.
  Tight hip flexors

• Anomalies that were formerly connected to the lower back. Research indicates that standing with straight legs and performing core-strengthening workouts can worsen lordosis. The iliopsoas muscle group, which is mainly used in workouts like sit-ups and straight leg lifts, appears to strengthen this muscle, according to anatomic theory. As a result, the athlete can be more susceptible to injury from particular training plans and sporting activities that exacerbate postural issues.
• The hamstrings lengthen in concert with hip flexion and knee extension during running and kicking; this lengthening may result in microscopic muscle damage or push the muscle to its mechanical limits.
  
• A hamstring injury may arise from an uncoordinated contraction of the biceps femoris muscle due to an imbalance in the dual nerve supply.
• There should be more discussion on the variations in the design of the hamstring muscles. This allows for more muscle flexibility and reduces the risk of overextending during eccentric contraction.
• The hamstring muscle group is stretched out when there is an excessive anterior pelvic tilt, and some research suggests that this could raise the likelihood of strain injuries.

How Is a Hamstring Strain Diagnosed?

• A trainer or physical therapist may diagnose a hamstring strain while you’re sitting on the sidelines. Getting frequent medical attention is also necessary if you have a hamstring problem. The doctor will examine your leg and enquire about the nature of the injuries and the degree of your discomfort.

The assessment will assist in determining your level of strain:

• Grade 1: It’s a light strain. When you use your leg, you could feel some slight pain and swelling, but nothing severe.
• Grade 2: It is possible to walk with a limp and experience pain at work. Not only may you be unable to fully extend your leg, but you may also notice some swelling and bruises.
• Grade 3: You will immediately observe swelling, experience pain, and be unable to fully extend your leg. Walking will be quite difficult, and crutches may be required.

Differential Diagnosis

• For example, the physiotherapist may need to differentiate between multiple injuries during the patient’s assessment.
• sciatica, hamstring tendinitis, adductor strains, avulsion injuries, piriformis syndrome, lumbosacral referred pain syndrome, and ischial bursitis.
• It is crucial to consider alternative reasons for posterior thigh soreness that could be misdiagnosed as hamstring strains throughout the diagnostic process. Certain tests and imaging are used to assess and rule out those different pain-causing possibilities.
• Restrictions on the sciatic nerve’s range of motion can exacerbate posterior thigh pain; in certain cases, discomfort may be solely due to adverse neurological strain when there isn’t a specific muscle injury. Sometimes it’s hard to tell if the injury is to the hip adductors (e.g., M. Gracilis and M. Adductor Magnus and Longus) or the hamstrings because of their close closeness. Sometimes imaging examinations are required to identify the exact location of the damage.
• Strains in the popliteus muscle, tendonitis at either gastrocnemius origin, sprained posterior cruciate ligament, and apophysitis (pain in the ischial tuberosity), Other conditions that resemble the look of hamstring strains include lesions in the upper tibiofibular joint and illnesses of the lumbar spine.

Diagnostic Procedures of Hamstring Strain:

• Most acute injuries can be easily identified by asking the patient to recount how the injury occurred. To be certain, they must additionally examine the hamstrings.
• If the therapist is unsure, he may ask for medical imaging. This will eliminate all other possibilities.
• Radiographs: One benefit of radiography is that it allows one to distinguish between different pain etiologies. It is capable of differentiating between disorders of the bones (such as stress fractures) and the muscles (like muscular strain).
• Ultrasound (US): Because this type of imaging is so inexpensive, it is used extensively. The fact that it can dynamically visualize muscles makes it an even more useful tool. One disadvantage of the fact that it can dynamically visualize muscles makes it an even more useful tool. ultrasonography is that it needs to be performed by a professional with experience.
• Magnetic Resonance Imaging (MRI): A thorough image of muscle damage is provided by an MRI. Sometimes, subsequently, the images might not make it clear. In that case, the patient’s account provided to the therapist will have to be trusted.

Examination of Hamstring Strain:

• Running gait: The running gait is examined first during the physical assessment. Since they frequently manifest days after the initial damage, swelling and ecchymosis are not usually visible at the outset of the injury.
• Palpation: The posterior thigh can be palpated to determine the precise area affected by pain provocation and to assess if a palpable musculotendon unit defect is present or absent. To locate each hamstring muscle and tendon, do repeated resistance-free knee flexion-extension motions throughout a restricted range of motion while the patient is in the prone position. It is also possible to palpate the site of maximal discomfort and identify it about the ischial tuberosity. The overall measurements of the ischial tuberosity’s length, width, and centimeters between it and the location of the most discomfort are provided.
• Range of motion: Two common tests are used sequentially to measure the maximum length and flexibility of the hamstrings: the passive straight leg raise (hip) and the active knee extension test (knee). In the passive straight leg raise and the active knee extension test, a typical hamstring length should permit the hip to flex 80 degrees and 20 degrees, respectively. Given that these tests are frequently impeded by pain in athletes who have just had an acute injury, they might not be a reliable measure of musculotendon extensibility. Again, a bilateral comparison is recommended.
• The sprinters’ pelvis and opposite leg were strapped securely as they lay supine. Ten centimeters above the patellar base was where a conventional flexometer was placed. on the Borg CR-10 scale. The damaged leg’s values were stated as
• Knee flexion strength: The athlete was positioned in a prone position with their pelvis and opposing leg locked to measure their isometric knee flexion strength. The foot was in plantar flexion and the knee was extended. At progressively higher effort levels, three maximum voluntary isometric knee flexion contractions were executed. Every three seconds, there was a 30-second rest interval. The strongest force value obtained from the strength test was selected. It can be helpful to try to bias the lateral or medial hamstrings through internal or external rotation of the lower leg to identify the muscles tested.

How Can You Prevent a Hamstring Strain?

• The best defense against hamstring strains is to maintain strong muscles. The following are some strategies to help guard against them (as well as other sports injuries):
• Before engaging in strenuous exercise or physical activity, fully warm up. To get your muscles moving, do some jumping jacks or jog stationary for a minute or two. After that, perform some dynamic stretching; see an athletic trainer or your coach for instructions. Stretch your muscles gently using static stretches after playing, holding each stretch for at least 30 seconds.
• Maintain your year-round muscular strength and flexibility. Exercise frequently and follow a proper stretching regimen to prevent your muscles from being shocked during a strenuous workout
• As a general guideline, aim to increase your weekly mileage or time spent participating in sports by no more than 10%.
• Should you get thigh discomfort, you should stop your activity immediately. Give your hamstring some time to rest if you think you may have strained it. Resuming your activities shouldn’t happen until your damaged leg feels strong, the pain is gone, and you can move it as easily as your other leg.

What’s the Treatment for a Hamstring Strain?

• Fortunately, surgery is only required for the most serious muscle damage. The majority of hamstring strains heal on their own or with little medical assistance.

To treat a hamstring strain, consider the following advice:

• As quickly as possible after the injury, use the RICE formula:
• Rest: Try not to put any weight on your leg and reduce your walking if your doctor tells you not to.
• Ice: For the first 48 hours following the injury, use a bag of ice or a cold compress to minimize swelling. This should be done for 20 to 30 minutes every 3 to 4 hours until the swelling goes down, starting as soon as possible after the accident. Cover the ice or ice pack with a cloth.
• Compress: If your doctor advises it, support your leg and reduce swelling by using sports wraps or elastic bandages.
• Elevate: Keep your leg up when you are sitting or lying down.
• Take pain medicine: Non-steroidal anti-inflammatory medications (NSAIDs), such as ibuprofen, can help lessen leg pain and swelling. Certain doctors favor alternative medications such as acetaminophen. Discuss the recommended medication with your physician.
• Engage in strengthening and stretching activities. Your leg’s strength and flexibility can be increased by gradually adding some workouts (and, possibly, preventing the injury from recurring again). Your hamstring’s readiness for these exercises can be assessed by a physician, sports medicine specialist, or physical therapist.

Medical Management:

• Only in cases where the hamstrings are ruptured is surgery recommended. Almost every patient claimed that their situation had improved after surgery. According to research, 91% of respondents felt content following surgery and gave their level of contentment a 75% or higher rating. Muscle strength assessments after surgery varied from 45% to 88%. Physical inspection and follow-up confirm that all fixes were kept.

Physical therapy of Hamstring Strain:

• Your physical therapist will begin therapy to address your hamstring strain after talking with you about your alternatives for treatment. For a hamstring strain, physical therapy’s key objectives are to help you return to optimal function, minimize pain and swelling, regain normal strength, and restore normal flexibility and range of motion.
• Your physical therapist has a wide range of options when it comes to treating your hamstring strain. These could consist of:
• Ultrasound: A deep heating therapy called ultrasound can assist increase your hamstring’s affected tissues’ extensibility and circulation. Although evidence suggests that it may not provide the benefit formerly thought in musculoskeletal applications, your physical therapist may still employ this treatment.
• Massage: Improving scar tissue mobility can be achieved by massaging the damaged area.
• Electrical stimulation: During your hamstring rehabilitation, electrical stimulation may be utilized to achieve a variety of objectives. Your PT may utilize e-stim to improve the contraction of your hamstring muscles, lessen edema, or help you manage your discomfort.
• Kinesiology taping: To aid enhance hamstring muscle functions, some physical therapists employ kinesiology taping procedures. You can also use kinesiology tape to reduce bruises and edema around your hamstring muscles. Talk to your therapist about using K-tape as there hasn’t been much study on its use.
• Gait training: When recuperating from a severe hamstring strain, you might have to use crutches to walk. Your physical therapist should show you how to walk correctly and move from needing walking assistance to walking normally.
• Ice: To reduce swelling and pain during the acute stage of an injury, ice might be applied.
• Heat: To help your hamstring muscles relax up and increase tissue flexibility, your physical therapist could apply moist heat packs before stretching.

Therapeutic Exercise of Hamstring Strain:

• A therapeutic exercise is the most significant treatment your therapist can do for you. In addition to giving you particular exercises to perform in the clinic, your physical therapist will probably also recommend a regular at-home workout regimen. This puts you in charge of your care and lets you take charge of your rehabilitation from hamstring strains.

Exercises for a Hamstring Strain may include:

• Hamstring stretches: Exercises that stretch the hamstrings both dynamically and statically can aid with hamstring function. Stretching is one of the finest strategies to rebuild scar tissue that is formed during the healing process of injured muscle. Stretching should feel like a tug, but after a few minutes, it should stop feeling that way.
• Lower extremity strengthening exercises: Your physical therapist could recommend strengthening workouts for your hamstrings and surrounding muscles if you have a hamstring strain. Exercises ought to be easy to begin and painless. You can advance to more strenuous strengthening activities as your ailment recovers.
• Hip and core strengthening exercises: After suffering a hamstring strain, research suggests that strengthening your hips and core muscles will help you get back to your regular activities. During your hamstring rehabilitation, you can be prescribed advanced hip strengthening and dynamic abdominal strengthening exercises.
• Agility drills: Your physical therapist could assign you to increasingly difficult agility exercises, such as jumping and hopping, as your recovery goes on. When you return to active sports, understanding how to leap and land correctly can help you avoid hamstring and other lower-limb joint and muscle injuries.
• Balance and proprioception exercises: Your rehabilitation may include working on maintaining proper lower extremity awareness and balance. By doing so, you may make sure that your muscles are functioning correctly and maintaining the proper alignment of your hips, knees, and ankles as you run, jump, and walk.

Rehabilitation of Hamstring strain:

Phase 1

Goals:

• Protect healing tissue
• Minimize atrophy and strength loss
• Prevent motion

Protection:

• Stay clear of overly stretching your hamstrings either actively or passively.
• Avoid antalgic gait pattern
• Ice 2–3 times daily

Therapeutic exercise (performed daily):

• Stationary bike
• Single leg balance
• Balance Board
• Soft tissue mobilization (STM)/Instrument assisted (IASTM)
• Progressive hip strengthening
• Pain-free isotonic knee flexion
• Active sciatic nerve flossing
• Ice with sensory electrical stimulation (e.g. Conventional TENS)

Criteria for progression to the next phase:

• Normal walking stride without pain
• Painless isometric contraction during a prone knee flexion (90°) manual strength test against submaximal (50%–75%) resistance

Phase 2:

Goals:

• Restore your hamstring strength while exercising all ranges without experiencing any pain.
• Develop the pelvic and trunk’s neuromuscular control by gradually increasing movement speed to get ready for functional actions.

Protection:

• Avoid end-range lengthening of hamstrings if painful
• Ice
• Post-exercise, 10–15 min

Therapeutic exercise:

• Stationary bike
• Moderate to high-intensity treadmill use (gradual increases in pace and stride length), pain-free
• Isokinetic eccentrics in non-lengthened state
• Single-limb balance windmill touches without weight
• single-leg pose with an interruption (e.g. reaching, tossing a ball)
• Supine hamstring curls on Swiss ball
• STM/IASTM
• Nordic hamstring exercise
• Shuttle jumps
• Prone leg drops
• Lateral and retro band walks
• Sciatic nerve tensioning

Criteria for progression to the next phase:

• During the prone knee flexion (90°) manual strength test, full strength (5/5) without pain
• Pain-free forward and backward jog, moderate intensity
• Less than 20% less strength is lost than in the unaffected limb.
• Pain-free max eccentric in a non-lengthened state

Phase 3:

Goals:

• free of symptoms (such as tightness and discomfort) during all activities
• Typical hamstring strength throughout the whole range of motion and speeds, both concentric and eccentric
• improved trunk and pelvic muscular control
• Integrate postural control into sport-specific movements

Protection:

• Train within symptom-free intensity
• Ice
• Postexercise, 10–15 min, as needed

Therapeutic exercise:

• Treadmill moderate to high intensity as tolerated
• Hamstring dynamic stretching
• Isokinetic eccentric training at the end ROM
• STM/IASTM
• Plyometric jump training
• 5–10 yard accelerations/decelerations
• A windmill with one limb balanced and weighing down on an unstable surface
• sport-specific exercises

Criteria for return to sport:

• Complete strength without discomfort in the extended state examination posture
• bilateral alignment in the knee flexion angle of the highest force
• Full range of motion without pain
• recreation of movements unique to a sport at a competitive pace without experiencing any symptoms

Summary

• The damage that results from stretching one or more of these muscles to the limit is called a hamstring strain, also referred to as a strained hamstring. Mild hamstring strains might have little pain and a quick healing period.
• You may bend your knee and extend your hip by using the biceps femoris, semitendinosus, and semimembranosus, three muscles that go down the back of your leg from your thigh to your knee. The damage that results from stretching one or more of these muscles to the limit is called a hamstring strain, also referred to as a strained hamstring.

FAQs

References:

• Hamstring Strain. (n.d.). Physiopedia. https://www.physio-pedia.com/Hamstring_Strain
• Dhameliya, N. (2021a, September 24). HAMSTRING STRAIN . Samarpan Physiotherapy Clinic. https://samarpanphysioclinic.com/hamstring-strain/
• Hamstring Strain. (2023, July 18). WebMD. https://www.webmd.com/fitness-exercise/hamstring-strain
• Hamstring Muscle Injuries – OrthoInfo – AAOS. (n.d.). https://orthoinfo.aaos.org/en/diseases–conditions/hamstring-muscle-injuries/