Let's call it intuition, based on how the query is phrased! It could be incorrect and I would expect the OP to correct me in that case! Because if he can prove the point .. good for him!
The primary objective behind the 90/180 days time restrictions on absences is "continuity of residence in UK". The issue here is not whether he could have been treated here in the UK or was treatment only possible abroad, but whether continuity of residence was broken or not! By his own admission, he was employed in India during the 270 days absence (irrespective of the medical condition) - and this is not same as being sent on an oversees work assignment to his home country while salary and taxes get credited here in UK - which is evidence enough that continuity of residence is broken.
If one's medical condition is serious enough that the person has to travel to a foreign country to undergo medical treatment, I would take it that he would either be on leave (for some time, if not all) during the course of his treatment or not working at all.
HSMP_2007 wrote: I was out of UK for nine months for medical treatments and during this period no come in the UK but i have employed in the home country
Generally speaking, if one needs to undergo medical treatment (out-patient or requiring hospitalization) for a "critical or serious" medical condition (assuming here that OP's condition was serious enough that it warranted foreign travel), it is expected that:-
1. The employer will continue to pay the employee his wages until such time that his paid leave allowance is exhausted, beyond which the employer allows unpaid leave until the employee resumes his duty,
or
2. The employee resigns from the company (immediately or sometime during the course of his treatment) and is unemployed for some or all of the duration of his treatment,
and/or
3. The employee joins another company under new terms and conditions (e.g.- part-time).
As the OP has himself mentioned, he was not paid in UK during the 270 days absence, options 1 and 3 can be ruled out. And he has also mentioned that he was employed in India during this time (assuming employed = being paid a salary), so option 2 is also ruled out.
Assuming OP had a serious medical condition that warranted immediate treatment, that this treatment was not possible in UK (or fast enough, given NHS service standards) and also that the OP had to travel to a foreign country for treatment - in this case, to claim exceptional circumstances in ILR application the OP will need to provide sufficient evidence(s) from his GP and hospital consultants to prove that 1) his condition required immediate / quick medical attention, b) treatment and recovery time for the condition OP was suffering from, in general, is expected to follow similar timeline, and 3) treatment (immediate or otherwise) was not available / possible in UK.
This said, by OP's own admission, this 270 days absence is not his only absence in the 5 years. With other absences added to this figure of 270, the percentage of absences up and above the permissible limit (180) will increase thereby negatively affecting the case, specially so if the other (not-mentioned) absences aren't work related.
All IMHO ...
regards