Table 2

Associations between radiological grades and clinical severity, lay-off time, muscles involved, etiology and recurrence

TotalGrade 0Grade 1Grade 2Grade 3
Injuries20727 (13%)118 (57%)56 (27%)6 (3%)
Clinical severity
 Minimal5 (2%)1 (4%)4 (3%)00
 Mild29 (14%)12 (44%)13 (11%)4 (7%)0
 Moderate143 (69%)14 (52%)89 (75%)38 (68%)2 (33%)
 Severe30 (15%)012 (10%)14 (25%)4 (67%)
Lay-off time (days)*19±178±317±1022±1173±60
Muscles involved
 Biceps femoris150 (84%)101 (86%)45 (81%)5 (83%)
 Semimembranosus20 (11%)12 (10%)8 (14%)1 (17%)
 Semitendinosus9 (5%)5 (4%)3 (5%)0
Aetiology
 Trauma130 (64%)8 (31%)79 (69%)39 (70%)4 (67%)
 Overuse72 (36%)18 (69%)35 (31%)17 (30%)2 (33%)
Recurrence34 (16%)2 (7%)20 (17%)12 (21%)0
  • Radiological grades were classified according to Peetrons27: grade 0 negative MRI without any visible pathology, grade 1 oedema but no architectural distortion, grade 2 architectural disruption indicating partial tear and grade 3 total muscle or tendon rupture. Clinical severity was classified according to the football consensus26: minimal (causing absence of 1–3 days), mild (absence 4–7 days), moderate (absence 8–28 days) and severe (absence>28 days).

  • * Values are mean±SD.