Beta-endorphin (betaE) is an important reliever of pain. Various stressors and certain modalities of physiotherapy are potent inducers of the release of endogenous betaE to the blood stream. Most forms of exercise also increase blood betaE level, especially when exercise intensity involves reaching the anaerobic threshold and is associated with the elevation of serum lactate level. Age, gender, and mental activity during exercise also may influence betaE levels. Publications on the potential stimulating effect of manual therapy and massage on betaE release are controversial. Sauna, mud bath, and thermal water increase betaE levels through conveying heat to the tissues. The majority of the techniques for electrical stimulation have a similar effect, which is exerted both centrally and--to a lesser extent--peripherally. However, the parameters of electrotherapy have not yet been standardised. The efficacy of analgesia and the improvement of general well-being do not necessarily correlate with betaE level. Although in addition to blood, increased brain and cerebrospinal fluid betaE levels are also associated with pain, the majority of studies have concerned blood betaE levels. In general, various modalities of physical therapy might influence endorphin levels in the serum or in the cerebrospinal fluid--this is usually manifested by elevation with potential mitigation of pain. However, a causal relationship between the elevation of blood, cerebrospinal fluid or brain betaE levels and the onset of the analgesic action cannot be demonstrated with certainty.

Balneotherapy is appreciated as a traditional treatment modality in medicine. Hungary is rich in thermal mineral waters. Balneotherapy has been in extensive use for centuries and its effects have been studied in detail. Here, we present a systematic review and meta-analysis of clinical trials conducted with Hungarian thermal mineral waters, the findings of which have been published by Hungarian authors in English. The 122 studies identified in different databases include 18 clinical trials. Five of these evaluated the effect of hydro- and balneotherapy on chronic low back pain, four on osteoarthritis of the knee, and two on osteoarthritis of the hand. One of the remaining seven trials evaluated balneotherapy in chronic inflammatory pelvic diseases, while six studies explored its effect on various laboratory parameters. Out of the 18 studies, 9 met the predefined criteria for meta-analysis. The results confirmed the beneficial effect of balneotherapy on pain with weight bearing and at rest in patients with degenerative joint and spinal diseases. A similar effect has been found in chronic pelvic inflammatory disease. The review also revealed that balneotherapy has some beneficial effects on antioxidant status, and on metabolic and inflammatory parameters. Based on the results, we conclude that balneotherapy with Hungarian thermal-mineral waters is an effective remedy for lower back pain, as well as for knee and hand osteoarthritis.

Effect of thermal water with high mineral content on clinical parameters and quality of life of patients with chronic low back pain was studied. In this randomized controlled, single-blind, follow-up study, 60 patients with chronic low back pain were randomized into two groups. The treatment group received balneotherapy with thermal-mineral water, and the control group bathed in tap water. Changes of the followings were evaluated: visual analogue scale (VAS) for pain, range of motion for the lumbar spine, Oswestry index, EuroQol-5D and Short Form-36 questionnaires. In the treatment group, the mobility of the lumbar spine, the Oswestry index, the VAS scores and the EuroQoL-5D index improved significantly. SF-36 items improved significantly in the treated group compared with baseline except for two parameters. Our study demonstrated the beneficial effect of balneotherapy with thermal mineral versus tap water on clinical parameters, along with improvements in quality of life.

To study the effect of thermal mineral water of Nagybaracska (Hungary) on patients with primary knee osteoarthritis in a randomized, double-blind clinical trial, 64 patients with nonsurgical knee joint osteoarthritis were randomly selected either into the thermal mineral water or into the tap water group in a non-spa resort village. The patients of both groups received 30-min sessions of bathing, 5 days a week for four consecutive weeks. The patients were evaluated by a blind observer immediately before and at the end of the trial using Western Ontario and McMaster Osteoarthritis (WOMAC) indices and follow-up assessment 3 months later. Twenty-seven patients of the 32 patients who received thermal mineral water and 25 of the 32 of those treated with tap water completed the trial. The WOMAC activity, pain, and total scores improved significantly in the thermal mineral-water-treated group. The improvement remained also at the end of the 3-month follow-up. The WOMAC activity, pain, and total scores improved significantly also in the tap water group at the end of the treatment course, but no improvement was detected at the end of the 3-month follow-up period. The treatment with the thermal mineral water of Nagybaracska significantly improved activity, pain, and total WOMAC scores of patients with nonsurgical OA of the knee. Even after 3 months, significant improvement was observed compared to the scores before the treatment or to tap water treatment.

The aim of this study was to evaluate the effects of Neydharting mud-pack therapy on the clinical parameters and quality of life in patients with knee osteoarthritis. In this double-blind, randomized, follow-up study on 53 patients with knee osteoarthritis, one group received hot mud-pack therapy, whereas the other (control) group was treated with hot packs of a substance manufactured on 10 occasions for 2 weeks. Western Ontario and McMaster Universities Arthritis Index (WOMAC), EuroQoL-5D quality-of-life measure and need for analgesics and non-steroidal anti-inflammatory drugs were recorded before treatment, at the end of treatment (at Week 2), and at Weeks 6 and 12. The WOMAC and the EQ5D quality-of-life scores improved from the baseline to the end of treatment in both groups, and further improvement was observed during the follow-up period (p < 0.001, respectively, in both groups). The need for medications for knee joint pain improved in both groups, and these changes were significant only in the mud-treated group (p < 0.001), but not in the control group (p = 0.106) compared to baseline. The number of patients requiring medications for knee joint pain showed a continuous downward trend at the subsequent post-treatment visits by the mud-treated group, and these changes became significant by Visit 4 compared to baseline (p = 0.016). The control group showed only temporary and not significant decrease. The difference was not significant between the groups in any of the outcome parameters at any visits. The Neydharting mud pack has a favorable effect on the clinical parameters, quality of life, and need for medications in patients with knee osteoarthritis. To evaluate the chemical effect, the number of patients should be increased.