The treatment of non-union by pulsed electromagnetic fields combined with a Denham external fixator

Effect of pulsed electromagnetic fields on the bioactivity of human osteoarthritic chondrocytes

Low-frequency pulsed electromagnetic fields (PEMFs) are used for the treatment of human osteoarthritic cells in vivo without knowledge of underling principles. The authors evaluated the effect of PEMFs on human chondrocytes of the osteoarthritic knee in vitro. Biopsies of the cut femoral condyles after total knee arthroplasty were kept in a standard cell culture medium consisting of Dulbecco's modified Eagle's medium: nutrient mixture F-12, 10% fetal calf serum, PenStrept (Mediatech, Inc, Manassas, Virginia), and ascorbic acid for 4 days and randomly split into an exposed group (PEMF for 4 hours daily for 4 days at 75 Hz and 1.6 mT) and a control group. Both groups were retained for biochemical and polymerase chain reaction analysis (glycosaminoglycan and DNA levels). A P value less than .05 was considered significant.DNA analysis revealed no differences between groups and no increase in content after exposure (P=.88 and .66, respectively). The increase of glycosaminoglycans was 0.4±1.6 ng (95% confidence interval [CI], 1.4 to 0.5) and -0.5±1.8 ng (95% CI, 0.6 to -1.5) in the exposed and control groups, respectively, with no significant difference (P=.24). A smaller decrease of glycosaminoglycan and DNA levels was observed over 4 days in the exposed group compared with the control group, with no statistical significance. The authors concluded that low-frequency PEMFs do not significantly influence the biosynthetic activity of explantcultures of human osteoarthritic cells in vitro. Nevertheless, they may be suitable as an adjuvant to a larger treatment regimen.

Bone mass is preserved in a critical-sized osteotomy by low energy pulsed electromagnetic fields as quantitated by in vivo micro-computed tomography

The effectiveness of non-invasive pulsed electromagnetic fields (PEMF) on stimulating bone formation in vivo to augment fracture healing is still controversial, largely because of technical ambiguities in data interpretation within several previous studies. To address this uncertainty, we implemented a rigorously controlled, blinded protocol using a bilateral, mid-diaphyseal fibular osteotomy model in aged rats that achieved a non-union status within 3-4 weeks post-surgery. Bilateral osteotomies allowed delivery of a PEMF treatment protocol on one hind limb, with the contralateral limb representing a within-animal sham-treatment. Bone volumes in both PEMF-treated and sham-treated fibulae were assessed simultaneously in vivo using highly sensitive, high-resolution micro-computed tomography (microCT) over the course of treatment. We found a significant reduction in the amount of time-dependent bone volume loss in PEMF-treated, distal fibular segments as compared to their contralateral sham-treated bones. Osteotomy gap size was significantly smaller in hind limbs exposed to PEMF over sham-treatment. Therefore, our data demonstrate measurable biological consequences of PEMF exposure on in vivo bone tissue.

Electrical treatment of tibial non-union: a prospective, randomised, double-blind trial

Electrical stimulation in the treatment of bony non-union has been used in different forms for many years. However, there is still a lot of uncertainty about its efficacy. We, therefore, undertook a prospective, randomised, double-blind trial to try and determine its effect. Over a period of 5 years, 34 consecutive patients with a tibial non-union met our "criteria for inclusion". Each patient had an oblique fibular osteotomy, followed by a unilateral external fixator. They were then randomly allocated one of two machines. Group 1, the active group, received electrical stimulation from an active machine. Group 2, the dummy group, had an identical machine but without any current passing through the active coils. They were then followed up for 6 months and evaluated clinically and radiologically for bony union. Unfortunately, there was by chance, an imbalance in smoking habit between the two groups. The union rate in the subgroup that smoked was 75% (6/8) in the active group as compared to 46% (6/13) in the dummy group. The active group of non-smokers had 100% (10/10) union rate, compared to 67% (2/3) in the dummy group. Overall 24 out of the 34 patients progressed to union. Out of 18, 16 (89%) in the active group showed bony union as compared to 8/16 (50%) in the dummy. There was, thus, a statistically significant positive association between tibial union and electrical stimulation (odds ratio 8, 95% CI: 1.5-41, P=0.02).

Treatment of ununited tibial fractures: a comparison of surgery and pulsed electromagnetic fields (PEMF)

The use of pulsed electromagnetic fields (PEMF) is gaining acceptance for the treatment of ununited fractures. The results of 44 articles published in the English language literature have been compiled to assess the effectiveness of PEMF vs surgical therapy. For ununited tibial fractures, 81% of reported cases healed with PEMF vs 82% with surgery. After multiple failed surgeries, the success rate of PEMF is reported to be greater than with surgery; this discrepancy increases with additional numbers of prior surgeries. In infected nonunions, the results of surgical treatment decreased by 21% and were less than the results utilizing PEMF (69% vs 81%). In open fractures, surgical healing exceeded PEMF (89% vs 78%), whereas in closed injuries PEMF cases healed more frequently (85% vs 79%). In general, PEMF treatment of ununited fractures has proved to be more successful than noninvasive traditional management and at least as effective as surgical therapies. Given the costs and potential dangers of surgery, PEMF should be considered an effective alternative. Experience supports its role as a successful method of treatment for ununited fractures of the tibia.

Day case treatment of delayed union of fracture of the shaft of the tibia with an external fixator

We report six cases of delayed union of fractures of the shaft of the tibia treated by the application of an external fixator on a day case basis. All fractures united within 12 weeks.