Medical/biological study (experimental study)

Effect of pulsed electromagnetic fields on human tenocyte cultures from supraspinatus and quadriceps tendons med./bio.

By: Denaro V, Ruzzini L, Barnaba SA, Longo UG, Campi S, Maffulli N, Sgambato A

Published in: Am J Phys Med Rehabil 2011; 90 (2): 119-127

To study the effects of pulsed electromagnetic fields (PEMFs) on human tenocyte cultures and to assess whether PEMFs could represent a viable therapeutic option in tendon pathologies.

Human tenocytes (primary cells) were isolated from healthy supraspinatus and quadriceps tendons during shoulder arthroscopy (of six patients).

different characteristics of primary tenocytes (cell growth, cell cycle, collagen production and cut closure)

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: continuous for 12, 24, 36, 72 h, 5 days, 7 days or 14 days	magnetic flux density: 0.4 mT

Frequency	50 Hz
Type	magnetic field
Waveform	pulsed
Exposure duration	continuous for 12, 24, 36, 72 h, 5 days, 7 days or 14 days

Exposure source	solenoid
Setup	30 cm long solenoid with a diameter of 15 cm and 45 turns of 20-gauge magnetic wire
Sham exposure	A sham exposure was conducted.

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	0.4 mT	-	-	-	-

Exposed system:

molecular biosynthesis: collagen accumulation (Sirius red staining and spectrophotometry; at 5, 7 and 14 days after exposure)
cell function: cut closure (cut was produced mechanically in a cell monolayer and cell-free zone and cell density was measured at 12, 24 and 36 h after injury in the presence of PEMF; photography)
cell viability/cell division/proliferation: cell growth (cell counting) and cell cycle (DNA content via flow cytometry); at 72 h, 5 and 7 days after exposure
morphol./histopathol. changes: cell morphology (cell and nuclear shape; at 72 h, 5 and 7 days after exposure; phase contrast microscopy)

Investigated system:

Time of investigation:

Tenocyte growth, cell cycle, cell morphology analysis, and total collagen accumulation did not show any statistically significant differences between exposed groups and control groups. However, exposure to PEMF significantly accelerated cut closure at 12 and 24 h after the injury.

Study character:

de Girolamo L et al. (2013): Low frequency pulsed electromagnetic field affects proliferation, tissue-specific gene expression, and cytokines release of human tendon cells
Barnaba SA et al. (2012): Clinical significance of different effects of static and pulsed electromagnetic fields on human osteoclast cultures
Giombini A et al. (2007): Hyperthermia induced by microwave diathermy in the management of muscle and tendon injuries
Strauch B et al. (2006): Pulsed Magnetic Field Therapy Increases Tensile Strength in a Rat Achilles' Tendon Repair Model
Owegi R et al. (2006): Localized pulsed magnetic fields for tendonitis therapy
Nightingale EJ et al. (2005): Radiofrequency energy effects on the mechanical properties of tendon and capsule
Robotti E et al. (1999): The effect of pulsed electromagnetic fields on flexor tendon healing in chickens
Greenough CG (1996): The effect of pulsed electromagnetic fields on flexor tendon healing in the rabbit
Lin Y et al. (1992): Effects of pulsing electromagnetic fields on the ligament healing in rabbits
Binder A et al. (1984): Pulsed electromagnetic field therapy of persistent rotator cuff tendinitis. A double-blind controlled assessment