be on a hard surface, in a confortable supine position, with the lower limbs flexed. Interestingly, several reviews, including the Quebec Task Force (1987) and the Agency for Health Care Policy and Research (AHCPR) guidelines, have noted some benefit from limited rest and did not note any benefit from therapeutic exercise in the acute setting of mechanical low back pain^(24,25).
Rhythmic and smooth stretching exercises are recommended once the symptoms begin to subside (pain, paravertebral muscle spasm and antalgic scoliosis). In-bed lumbar traction is usually not recommended at this stage. Postural education and biomechanics should be initiated as early as possible. The patients should be encouraged to remain as active as tolerated early in the course of LBP. Malmivaara et al⁽¹⁶⁾, have shown the benefits of using return to graded functional activities in the management of low back pain, rather than a specific time of rest or structured exercise program.

Physical therapy
An accurate diagnosis of the causes of the LBP and treatment objectives play a definitive role in the determination of the type of physical therapy to be employed for LBP. Several treatment modalities have been recognized to date. However, very few control studies have definitely determined efficacy rate and outcomes. Pain syndromes are known for their multifactorial features and the different limitations, regarding the methodologies hinder the performance of randomized studies in the determination of clinical efficacy of specific treatment modalities. Additionally, a placebo effect can be present in up to one third of the cases receiving physical therapy⁽³⁰⁾.
The relief of acute pain demands local superficial or deep heat or ice pack therapy.
TENS (transcutaneous electrical nerve stimulation) is an alternative to relief the pain. It is easier to perform and well tolerated by the patients as a procedure to obtain analgesia.
Exercises are the cornerstone in the physical therapy and rehabilitation. This topic will be discussed in further detail elsewhere.
The lumbar traction is less used as treatment because, in certain situations, it can increase the pain.
Postural education, health ergonomics applied to the workplace and at home should also be recommended.

Schools for vertebral column rehabilitation – back school – have been producing good outcomes in diminishing the frequency of LBP.
In chronic cases with acute bouts of pain, the employment of braces and abdominal supporting belts (elastic belts) are effective in diminishing the pain. However, the abdominal belts should be worn only for a brief period of time to avoid atrophy and weakenss of the abdominal wall.
There is no clear-cut agreement about the indications of physical therapy for low back pain. For instance, Van de Hoogen et al(31) completed a prospective study cohort of prognostic factors for the resolution of low back pain. Forty percent of the eligible patients dropped out of the study, biasing the results for patients with more severe disorders, patients who received physical therapy had a slower improvement rate.
Treatment management planning, for patients with chronic manifestations, should take into account the affective and the nociceptive components of the pain. The delay in the recovery of patients with low back pain may be related to other factors unrelated to the patient's clinical status. Recovery can be strongly influenced by psychological and occupational factors. It should also be remembered that chronic low back pain patients become phisically unfit, requiring a more comprehensive assessment. Specific management of chronic LBP should include the following points: self-application, easiness, low cost, satisfactory efficacy.

Thermal agents
The application of heat or ice in the lumbar region aims at controlling the pain, muscle contraction, and the inflammatory reaction in certain cases.

Heat
Heat and cold have been known for some time to reduce pain. They appear to do so by equalizing the temperature gradient between injured and non injured tissues. In addition to relieving pain, these modalities have other actions, including effects on flexibility, joint stiffness, blood flow, and inflammation. To take advantage of these properties, both for treating pain and other conditions, numerous heating and cooling devices have been developed.