NHS Confederation primary care trust network director David Stout said joint appointments such as public health directors ensure health is on the local government 'radar' when decisions about care priorities and funding are taken.
But he warned that the decision to joint appoint to any post should be a local one, and areas should not be set central targets to boost partnerships.
His claims followed a report published by the Local Government Association in which 68 per cent of social services departments claimed the financial deficit in the local NHS has seen costs pushed onto local government, to the detriment of services.
Nearly half, 49 per cent, said that cost-shunting had resulted in the closure of beds, 21 per cent in the reduction of district nursing capacity and 15 per cent in increased waiting times.
The survey also showed 39 per cent found increased referral of cases that appear to have NHS responsibility; 24 per cent reported a failure to fully fund agreed or jointly funded services; 4 per cent found an increasing number of funding disputes and 13 per cent reported a withdrawal from local area agreements, which bring together local public services and their partners to agree priorities.
The NHS Confederation said the LGA's decision to go public with the survey was 'frustrating', and that it failed to reflect the costs the NHS was picking up due to social services tightening eligibility criteria. It instead called for closer working.
Mr Stout said: 'It's not that uncommon to have a joint appointment in public health and it's definitely worth doing along with sharing human resources, IT and estates.
'People's health is often determined by issues under the control of local authorities such as antisocial behaviour, employment and housing. A joint appointment ensures public health is on the local government radar.'
Last year's local government white paper Strong and Prosperous Communities, recommended 'wider use of joint appointments of senior managers between local authorities and NHS bodies'.
David Stout said he knew of no official strategy to ensure joint appointments were being put in place. But he added: 'I am not sure we need mechanisms such as performance targets as we are pushing for local decisions and local accountability. Joint appointments should be driven by local determination because it will provide better care for the population.'
Public health directors are the most common joint appointments to date. Public health minister Caroline Flint told the Commons last month that more that 70 per cent of public health directors were jointly appointed following reorganisation.
Liam Hughes, who has been seconded from the NHS to local government's Improvement and Development Agency to head up joint work on public health, said: 'It's very important to reach a position of financial stability as soon as we can to meet the requirements for joint working.'
Mr Stout said he felt there was cause for optimism as only 40 per cent of those surveyed by the LGA believed the situation would worsen.
He said this could be because of local area agreements, which have been piloted in several areas but are now being developed nationally.
Mr Stout said: 'There are different opportunities with the LAAs, using them as the means of setting out joint objectives between local government and local health authorities.
'Under the LAA organisations can share performance management and national performance-management recognises that local targets are as important as national ones.
'An integrated framework can set out what needs to be achieved within the financial reality and get away from to-ing and fro-ing between PCTs and local authorities.
'There are already integrated commissioning structures in some areas and it will become common practice where there is coterminosity - which now occurs more frequently following reconfiguration.'