Table 1 Main clinical features of the 6 patients
Case 1 | Case 2 | Case 3 | Case 4 | Case 5 | Case 6 | |
|---|---|---|---|---|---|---|
Sex | Female | Female | Male | Male | Male | Female |
Age at stress reaction/stress fracture (years) | 10 | 5 | 9 | 4 | 5 | 11 |
Months since diagnosis of JDM (months) | 3 | Prior to JDM diagnosis | 7 | 18 | 9 | 20 |
Symptoms | Right lower leg pain | Tenderness over the right shin | Bilateral knee pain | Right shin pain | Bilateral shin pain | Right shin pain |
Stress reaction or stress fracture | Stress fracture | Stress fracture | Stress reaction | Stress reaction | Stress reaction | Stress fracture |
Location of stress reaction/stress fracture | Middle and lower third of right tibia, right proximal fibula | Bilateral proximal tibiae | Middle third of bilateral tibiae | Middle diaphysis of the right tibia | Bilateral anterior cortical tibiae | Middle diaphysis of the right tibia |
JDM therapy at stress reaction/stress fracture | Prednisone 1.2 mg/kg/day | No treatment | Prednisone 0.6 mg/kg/day, MTX | MTX | MTX | MTX |
Interventions for stress injury/stress fracture | Rest and analgesics | Rest | Rest | Rest | Rest | Rest |
Physical function before tibial lesion | Limitation of extracurricular activities only | Limitation of instrumental daily activities | No limited activities | No limited activities | Limitation of extracurricular activities only | No limited activities |
Muscle weakness in lower extremities at time of tibial lesion | No | Yes | No | No | Yes | No |
Modified disease activity score at stress reaction/stress fracture (0–11) | 2 | Not evaluated | 1 | 1 | 3 | 3 |
Age matched BMD | Normal range | Normal range | Normal range | Not evaluated | Normal range | Normal range |
Regional osteoporosis or osteopenia | No | No | No | Osteopenia | No | No |
Serum 25-hydroxyvitamin D prior to stress reaction/stress fracture, nmol/L | 65 | Not measured | 19 | 113 | 100 | 45 |