Role of percutaneous bone marrow grafting in delayed unions, non-unions and poor regenerates.

The present study comprises of 72 patients of post traumatic delayed unions, established non-unions, poor regenerate in segmental bone transportation and limb lengthening procedure treated by percutaneous injections of autogenous bone marrow at the site of failed healing. The average follow up was 4 years. Bone union was achieved in 68 patients. Overall, 72.2% of the patients had an excellent result, 11.1% a good result, 11.1% a fair result and 5.5% a poor result or failure. These results with only 4 failures (5.5%) are encouraging and suggest that percutaneous autogenous bone marrow grafting is a simple, safe and useful technique in the treatment of delayed unions and non-unions. We believe that this technique of percutaneous autogenous bone marrow grafting can be a procedure of choice in those patients where Phemister or Forbes methods of bone grafting alone is required, especially in limbs with scarred and poor soft tissue coverage. This procedure can also be useful in iatrogenic delayed or non-unions which is the commonest cause of non-union in present era of enthusiastic fracture fixation.

Pulsed electromagnetic fields for the treatment of bone fractures.

The effectiveness of electrical stimulation and Pulsed Electro Magnetic Field (PEMF) stimulation for enhancement of bone healing has been reported by many workers. The mechanism of osteogenesis is not clear, therefore, studies look for empirical evidence. The present study involved a clinical trial using low amplitude PEMF on 19 patients with non-union or delayed union of the long bones. The pulse system used was similar in shape to Bassett's single pulse system where the electric voltage pulse was 0.3 mSec wide repeating every 12 mSec making a frequency of about 80 Hz. The peak magnetic fields were of the order of 0.01 to 0.1 m Tesla, hundred to thousand times smaller than that of Bassett. Among the 13 who completed this treatment schedule the history of non-union was an average of 41.3 weeks. Within an average treatment period of 14 weeks, 11 of the 13 patients had successful bone healing. The two unsuccessful cases had bone gaps greater than 1 cm following removal of dead bone after infection. However, use of such a low field negates Bassett's claim for a narrow window for shape and amplitude of wave form, and justifies further experimental study and an attempt to understand the underlying mechanism.

Effect of pulsed electromagnetic field on healing of experimental nonunion in rat tibiae.

To see the effect of Pulsed Electromagnetic Field (PEMF) on nonunited fracture healing, nonunion was induced in rat tibiae and PEMF was applied on it. Out of five different techniques utilised for inducing nonunion soft tissue interposition was found to be the most suitable and effective method of experimental induction of nonunion. Twenty eight experimental and 15 control rats were finally evaluated for the effect of PEMF applied for up to 8 weeks. After sacrifice of 8 experimental and 4 controls, 6 experimental and 3 controls, again 6 experimental and 3 controls and finally 8 experimental and 5 controls at 2, 4, 6 and 8 weeks respectively of PEMF application no significant difference as to the quality of healing was observed between the experimental and control animals. It was thus concluded that PEMF appeared to have no beneficial effect on the healing of nonunited fractures in experimental set-up.