[Bone healing and biochemical blood parameters after arteficial osteotomy of rabbits' femur treated by low-frequency magnetic field].

Wiener klinische Wochenschrift · 2001 · Benefit · Low evidence

← Research stream

BenefitLow evidencePaper 3862

Study snapshot

PublicationWiener klinische Wochenschrift · 2001

Study typeanimal

Reported directionBenefit

Evidence ratingLow

Abstract

Aim of the study was to investigate the effect of magnetic fields on bone fracture healing and biochemical indices of bone turnover. Young male "White Newzealand Rabbits" were exposed after osteotomy of the femur of the hind-paw in narcosis for 31 days in a low-frequency magnetic field (field parameters: frequency 15.3 Hz, signal form: sine, magnetic field strength: 50 microT peak value). Eight animals each were assigned randomly for a single blind study to 3 groups. Controls were kept in a sham-exposition cage without magnetic field influence and were compared with a group in (Pseudo-) Helmholtz-coil arrangement with a horizontal magnetic field and a further group in a cylinder coil (vertical magnetic field). The daily duration of stay in the (sham-) exposition arrangements amounted to 30 minutes respectively. The activities of the alkaline phosphatase (AP) and creatinkinase (CK) were evaluated preoperatively, after the 19th and 31st experimental day, the callus density by means of computertomography after the 31st experimental day (two-tailed t-test). The densitometrically assessed callus densities of the magnetically treated groups were highly significant (p < 0.0001) compared with the controls. In spite of accelerated fracture healing the activities of the ALP were lower at both postoperative examinations than preoperatively, in the cylinder-coil the activity proved to be significantly lower (p < 0.05) compared with the controls after 31 days. Significant differences in CK were detected at no time. In conclusion, we confirm the positive magnetic field effects on fracture healing. The mechanisms of interaction of magnetic field and bone fracture healing remain to be clarified.

Machine Enhanced Logic

AI evidence extraction

Structured fields below were generated from the paper’s abstract and metadata to make the evidence easier to inspect. Automated extraction may be incomplete or incorrect; verify important details against the original paper.

Study typeanimal

Effect directionbenefit

PopulationYoung male White Newzealand rabbits after femur osteotomy

Sample size24

ExposureELF · 0.0153 MHz · 30 minutes/day for 31 days

Evidence strengthLowConfidence: 78% · Peer reviewed: yes

Main findings

Rabbits exposed to a 15.3 Hz, 50 microT (peak) magnetic field for 31 days had higher CT-assessed callus densities than sham-exposed controls (p<0.0001). ALP activity was lower postoperatively than preoperatively in all groups, and in the cylinder-coil (vertical field) group ALP was significantly lower than controls at day 31 (p<0.05). No significant differences in CK were detected.

Outcomes measured

Bone fracture healing (callus density by CT at day 31)
Alkaline phosphatase (AP/ALP) activity
Creatine kinase (CK) activity

Limitations

Animal model (rabbits) may not generalize to humans
Small group sizes (8 animals per group)
Single-blind design (details of blinding not provided in abstract)
Only one exposure frequency/intensity and one daily exposure duration studied
Mechanisms not clarified (as stated by authors)

View raw extracted JSON

{
  "study_type": "animal",
  "exposure": {
    "band": "ELF",
    "source": "therapeutic magnetic field (coil exposure)",
    "frequency_mhz": 0.0153,
    "sar_wkg": null,
    "duration": "30 minutes/day for 31 days"
  },
  "population": "Young male White Newzealand rabbits after femur osteotomy",
  "sample_size": 24,
  "outcomes": [
    "Bone fracture healing (callus density by CT at day 31)",
    "Alkaline phosphatase (AP/ALP) activity",
    "Creatine kinase (CK) activity"
  ],
  "main_findings": "Rabbits exposed to a 15.3 Hz, 50 microT (peak) magnetic field for 31 days had higher CT-assessed callus densities than sham-exposed controls (p<0.0001). ALP activity was lower postoperatively than preoperatively in all groups, and in the cylinder-coil (vertical field) group ALP was significantly lower than controls at day 31 (p<0.05). No significant differences in CK were detected.",
  "effect_direction": "benefit",
  "limitations": [
    "Animal model (rabbits) may not generalize to humans",
    "Small group sizes (8 animals per group)",
    "Single-blind design (details of blinding not provided in abstract)",
    "Only one exposure frequency/intensity and one daily exposure duration studied",
    "Mechanisms not clarified (as stated by authors)"
  ],
  "evidence_strength": "low",
  "confidence": 0.78,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "bone healing",
    "fracture healing",
    "osteotomy",
    "rabbit",
    "low-frequency magnetic field",
    "ELF magnetic field",
    "15.3 Hz",
    "50 microT",
    "callus density",
    "alkaline phosphatase",
    "creatine kinase",
    "Helmholtz coil",
    "cylinder coil"
  ],
  "suggested_hubs": [
    {
      "slug": "therapeutic-emf",
      "weight": 0.7,
      "reason": "Study tests low-frequency magnetic field exposure as a treatment affecting fracture healing."
    }
  ]
}

AI can be wrong. Always verify against the paper.

AI-extracted fields are generated from the abstract and metadata and may be incomplete or incorrect. This material is for informational purposes and is not medical advice.

Identifiers and source

DOI: Not supplied
PubMed: 15503621

Read the original paper →

Related papers

← Back to the Research Library