Hamstring injury

Hamstring injuries are the most common muscle injury, and are very common in athletes and can cause a significant loss of playing time depending on the sport.

Epidemiology

Amongst professional athletes, hamstring injuries are reported to make up 15% of all injuries in Australian Football players and 12% of injuries amongst soccer players .

Pathology

Location

As with any muscle injury, the hamstrings can be injured at multiple possible points :

• origin: ischial tuberosity avulsion injury
• proximal free tendon
• myotendinous junction (most common)
  • proximal more commonly injured than distal
  • biceps femoris most common hamstring muscle injured
• epimysial/myofascial: most common in biceps femoris proximal to the fusion of the short and long heads
• intramuscular (rare)
• distal free tendon
  • semitendinosus distal tendon injury (most common)
  • semimembranosus distal tendon injury

Mechanism

Hamstring injuries can result from :

• acute injury
  • type 1
    • eccentric contraction during high-speed running for limb deceleration in preparation for foot strike
    • proximal myotendinous junction of biceps femoris most commonly injured
  • type 2
    • excessive lengthening of the hamstring (e.g. dancing, slide tackles, high kicking)
    • proximal free tendon of semimembranosus
• chronic overuse
  • most commonly seen in runners (over all distances)
  • proximal hamstring origin tendinopathy, with semimembranosus most commonly affected

Classification

Clinically, hamstring injuries can be graded as :

• grade 1: no appreciable muscle tearing, <5% loss of function/strength
• grade 2: damage to the musculotendinous junction (MTJ); reduced strength; some residual function
• grade 3: complete tear of the MTJ; loss function +/- a palpable gap

There are numerous imaging classification systems including:

• British Athletics muscle injury classification (MRI-based)

Radiographic features

There are no unique features of hamstring-specific injuries. Please see the general articles on muscle injury and tendon pathology for further details.

Treatment and prognosis

Return to play is largely predicted by clinical assessment with poor correlation between imaging-based grading systems and time to return to play . Prognostic factors affecting a longer rehabilitation and thus delayed return to play include :

• proximal free tendon injury
• proximity to the ischial tuberosity
• ≥ grade 3 injury (i.e. grade 1 and 2 injuries are not associated with time to return to play)

The recurrence rate is ~20% (range 12-31%) and can occur within a short timeframe (e.g. 2 weeks) after return to play .

Differential diagnosis

Patients presenting with posterior thigh pain suspicious for a hamstring injury but have a negative MRI (so-called "MRI-negative hamstring injury") may have symptoms from :

• lumbar spine referred pain
• fascial injury
• gluteal trigger points

Siehe auch:

• Morbus Osgood-Schlatter
• Avulsionsfraktur Basis Metatarsale 5
• Tuber ischiadicum
• Stieda-Pellegrini-Köhler-Schatten
• Avulsionsfraktur
• Oberschenkelmuskeln
• calcaneal tuberosity avulsion fracture
• Morbus Sinding-Larsen-Johansson
• Rotatorenmanschette
• Patellaspitzensyndrom
• Ansatz ischiocrurale Muskulatur
• Abrissfraktur Epikondylus ulnaris
• Musculus subscapularis
• Avulsionsfraktur der Tuberositas tibiae
• Adduktorenruptur
• distal tears of the hamstring muscles

und weiter:

• Musculus biceps femoris
• Knochenanker
• Ischiocrurale Muskulatur
• tear distal biceps femoris tendon
• proximaler Hamstringausriss