Hamstring Strain Treatment & Management

Physical Therapy

The key to successful recovery from a hamstring strain is recognition of the injury and of the severity of the stain. Physical therapy (PT) is the mainstay of treatment. ^[13] The program depends on the severity of the injury and on the time that has elapsed since the injury. Very few scientific data are available to determine specific rehabilitation and treatment protocols for hamstring injuries. The program below is just a guide and should be tailored to individual patient needs.

Acute phase

During the acute phase (1-5 d), most of the treatment is geared toward decreasing the inflammation and maintaining range of motion. As for most strains, PRICE (ie, protection, rest, ice, compression, elevation) is the initial treatment. When the pain has decreased, the therapist may begin painless gentle passive range of motion and active-assistive range of motion. The patient also may benefit from a cane or crutches to aid in ambulation to keep active. Even if a patient with a first-degree injury is feeling better after a few days and wants to return to participating in his or her sport, it is usually recommended that he or she complete a rehabilitation program to avoid chronic injury. Muscle strengthening, balance, and stretching should be emphasized to the patient as a prevention of recurrence. ^{[14, 15]}

Subacute phase

The subacute phase (5 d to 3 wk) is when the inflammation of the injury appears to be lessening. The goal of treatment in this stage is to begin some active range of motion and start strengthening. Aquatic therapy is helpful in encouraging activity with decreased weight bearing. Pain-free submaximal isometric exercises also are encouraged. A transcutaneous electrical nerve stimulation unit may be used to provide some pain relief at this time. Ice is also helpful to decrease pain and inflammation. The patient also should resume cardiovascular training, which may include swimming with a pull buoy between the legs, and upper extremity exercises.

Remodeling phase ^[3]

The remodeling phase (1-6 wk) is when the patient is able to perform isometric exercises at 100% effort without pain. Prone isotonic hamstring exercises are now added to the transcutaneous electrical nerve stimulation unit and ice. Begin unilaterally with ankle weights, using low weight and a high number of repetitions. Slowly increase the weight as tolerated as long as the patient's pain is not increased afterwards. Importantly, do not increase the weight too rapidly because this could lead to a chronic injury.

Once concentric strengthening is tolerated at a normal level, the patient may begin eccentric strengthening. Because this exercise puts the most strain on the muscle, supervised exercising and slow progression of weight is recommended. In the prone position, the patient performs a unilateral contraction to 90° of knee flexion and then slowly lowers the weight. If the patient experiences pain or stiffness, then decrease the weight to a more tolerable amount. When the affected leg is within 10% of the unaffected leg, then the patient may advance to a more aggressive therapy program. Continued stretching of the hamstring is essential and should occur prior to exercise. Moist heat prior to exercise may provide improved results. A posterior pelvic tilt may help eliminate lumbar compensation.

Functional stage

The functional stage is 2 weeks to 6 months. At this point, the patient should have a normal gait pattern and can begin fast walking. When the patient can ambulate for 20-30 minutes at a fast speed without pain or stiffness, short periods of jogging can be added to the fast walking. When the patient can perform a 15- to 30-minute jog, then short periods of sprinting may be added to the jog. Eventually, more sport-specific exercises may be added. Have the patient continue with the hamstring strengthening and stretching throughout this stage.

During the later stages of therapy, plyometric exercises may be used to increase speed and power during training. These exercises consist of muscle stretching followed by concentric contraction, allowing for a stronger contraction because of muscle facilitation and decreased inhibition. Low-level exercises may be used initially (eg, jumping rope), followed by higher-level exercises as tolerated (eg, side jumping over a low object, jumping onto and off a box). Because the higher level exercises are associated with a higher rate of injury, they should be performed with supervision.

Return to play

This can occur anywhere between 3 weeks and 6 months. Isometric strength testing and flexibility testing may be performed prior to returning to play to ensure that no subtle deficits are present that may lead to chronic injury. ^[16] The clinician must impress upon the patient the importance of stretching and warm-up prior to activities to prevent reinjury. Less than 5 weeks are required before return to play for patients with (1) superficial muscle injury or (2) muscle injury that involves a small cross-section of muscle. In patients whose injury was due to poor biomechanics, care should be taken to correct the underlying cause. The patient should be supervised during stretching and exercise in order to assess poor technique and correct it.

In a study of 59 Australian footballers who had incurred a hamstring strain, Warren et al found evidence that 2 factors—the amount of time it took a player to walk without pain and whether or not the player had suffered a previous hamstring injury—could be used to help predict the length of time needed for the athletes to return to competition and how likely it was that the injury would again recur. ^[17] According to the study, players who needed more than 1 day to walk without pain were more likely to require more than 3 weeks of convalescence before they could again compete.

A prospective study by Guillodo et al indicated that in patients who suffer hamstring injury, a visual analogue scale pain score of more than 6 and, for over 3 days, the occurrence of pain during everyday activities predicts a time to full recovery of more than 40 days. The study was conducted on 120 athletes, who were assessed by sports medicine specialists within 5 days of suffering an acute hamstring injury. ^[18]

A randomized, double-blind, parallel-group trial by Silder et al found that two different types of rehabilitation programs for acute hamstring injury—(a) progressive agility and trunk stabilization and (b) progressive running and eccentric strengthening—were each similarly effective to the other in terms of recovery. The study involved 25 patients who completed one of the two programs, with magnetic resonance imaging (MRI) and physical examinations performed prior to and after rehabilitation. Injury resolution was found to be nearly, but not totally, complete in all subjects at the time of return to sport. ^[19]

A study by Tyler et al found that in hamstring-strain injuries, reinjury after return to play is discouraged by a rehabilitation program that focuses on eccentric strength training with the hamstrings in a lengthened position. Among 50 athletes, 42 who were compliant with the program had sustained no reinjuries by an average of 24 months after returning to sport, while among eight noncompliant athletes, four suffered reinjury between 3 and 12 months following their return to sport. Moreover, full strength had been restored to the compliant athletes by the time they returned to sport, while significant hamstring weakness was experienced by the noncompliant athletes. ^[20]

Need for surgical intervention is extremely rare after a hamstring injury. Surgery is recommended only in the case of complete rupture of the proximal or distal attachment of the myotendinous complex into the bone. ^[21]