HEAT AND COLD IN THE PHYSICAL TREATMENT OF RHEUMATOID ARTHRITIS OF THE KNEE

Transcription

1 ORIGINAL PAPER HEAT AND COLD IN THE PHYSICAL TREATMENT OF RHEUMATOID ARTHRITIS OF THE KNEE A CONTROLLED CLINICAL TRIAL BY J. A. KIRK AND G. D. KERSLEY Royal National Hospital for Rheumatic Diseases, Bath A STANDARD practice in the physical treatment of the chronically inflamed joint consists of some form of thermal application followed by active exercises. The controversy over the relative value of hot and cold applications extends back at least to the time of Hippocrates. At the present time both forms are used in the treatment of joints involved with rheumatoid arthritis, with clinical experience generally favouring heat therapy (Kuhns, 1954), although cold in the form of ice packs is becoming more widely used (Moore, 1964; Haines, 196). In view of the lack of controlled observation on the therapeutic results of heat and cold therapy we have carried out a comparative clinical trial of these treatments in patients with chronic rheumatoid arthritis involving the knee joint. MATERIAL From patients admitted to hospital for treatment of chronic rheumatoid arthritis, 14 patients (0 knees) were selected for study. All had definite or classic rheumatoid arthritis (Ropes et ah, 1959) of between two and 5 years' duration (mean 14 years); 1 of the 14 patients were seropositive and 6 were receiving longterm oral corticosteroid therapy. Only patients with serious knee-joint involvement were included in the trial, although in all cases several other joints were affected. In 14 knees a fixed flexion deformity greater than 15 degrees was present; in 1 there was clinically active synovitis and in 14 extensive radiological cartilage loss. METHOD The trial period lasted five weeks for each patient. Daily during the second and fourth weeks each knee received either ice or hot pack treatment followed by a standard exercise programme. The treatments were allocated at random so that first each knee received a five-day period of ice packs or a five-day period of hot packs, and then after a nine-day treatment-free interval the other treatment was given in a crossover fashion. 0

2 KIRK AND KERSLEY: TREATMENT OF RHEUMATOID ARTHRITIS 1 DETAILS OF TREATMENT HOT PACKS These consisted of Hydropak 4 X 5 inches, boiled for 0 minutes, wrapped in six layers of Turkish towelling and one layer of polyethylene. The pack was wrapped around the knee for 0 minutes, the temperature at skin-towel junction being approximately 45 C. at the beginning and 41 C. at the end of treatment. ICE PACKS These consisted of 1,000 c.c. of melting crushed ice at 0 C. (Icematic machine) wrapped in one layer of damp towel. A 5-inch-wide pack was made long enough to surround the knee. ASSESSMENTS The following assessments of each knee were made by two observers at the same time of day during the first (pretreatment), third (crossover), and fifth (post-treatment) weeks. (1) Pain and stiffness, each graded 0 (none) to 5 (severe). () Range of movement and knee circumference measured from intradermal indian-ink markings, using a long-armed goniometer and cloth tape measure. (3) Joint temperature: hand assessment of the skin warmth over the knee compared with the leg above and below, graded 0 (normal) to 3 (warm). In eight knees the temperature was further assessed by radiometer (bolometer) measurement of infrared-heat emission. On three consecutive days during each assessment week the whole limb was exposed to a constant temperature (0 C.) for 60 minutes. Repeated readings were taken over the patella and compared with readings from the thigh 8 cm. above the patella and leg 8 cm. below. During the trial patients were subjected to the normal hospital regimen, including rest periods, hydrotherapy, and resting leg splints as therapeutically indicated. RESULTS In spite of the comfort of hot applications, the larger number of patients (and knees) preferred ice packs (Table I). TABLE I TREATMENT PREFERENCE Cold Heat None _ Total Knees Patients

3 ANNALS OF PHYSICAL MEDICINE VOL. IX NO. All but two patients had no difficulty in deciding on a preference and, as expected, this was the treatment which appeared best to relieve pain and stiffness. TABLE II TOTAL IMPROVEMENT IN GRADES OF PAIN AND STIFFNESS Pain.. Stiffness.. Cold 6 Table II shows that improvements in grade of pain and stiffness in the 0 knees coincided more with cold than heat therapy, although these numbers are insufficient to reach statistical significance. Though the results of knee temperature assessments were sometimes conflicting, neither method revealed any difference between the two treatments. The radiometer showed that the average knee temperature did not appreciably alter after the treatment periods (+0-05 C. following ice and 0- C. following heat), whereas hand assessments indicated that knees tended to cool during the trial period if initially warm. The change in hand-appreciated knee temperature in the 0 knees was similar after heat and cold, a total of eight grades of cooling following each. There was a satisfactory correlation between manual and radiometer measurements of knee warmth after 10 of the 16 treatment periods in which, both were employed, but in the remaining six correlation was poor. Similarly, the slight diminution in knee circumference over the trial period did not appear to coincide with one or other treatment (average lessening in knee girth: ice 0-18 cm., heat 0-1 cm.). The average range of knee movement did, however, improve significantly, but equally after both forms of therapy (3-8 degrees per knee with cold and 3-4 degrees with heat). There was no consistent correlation between the type of knee disease and the response to a particular treatment. Over the whole group, active synovitis or flexion contractures did not respond better to one treatment or the other, although in individual patients the total improvement frequently occurred after one treatment week. Where both knees were being studied, the patient's preference for one knee was always the same as that for the other, although in several cases the character of knee involvement was dissimilar. In general, both treatments were well tolerated and the initial unpleasantness of the ice application was not regarded as significant by the patients. One female patient developed an ice burn over a fat pad; a blotchy erythematous rash persisted with some discomfort for 48 hours. The same patient complained of headaches after ice applications, and stated heat as her preference, although ice packs were followed by a greater relief of pain and stiffness. Heat 6

4 KIRK AND KERSLEY: TREATMENT OF RHEUMATOID ARTHRITIS 3 DISCUSSION In view of the "soothing" effect of heat in rheumatoid arthritis and the association between worsening of symptoms and cold or weather change, it is to be expected that cold therapy would not appeal to many rheumatoid arthritic patients (Knott, 1964). However, this was not confirmed in this trial, in which only one patient disliked cold applications and preferred heat in spite of a lesser symptomatic benefit. The remainder of the patients placed little importance on the immediate effect of treatment and based their preference on the change in joint pain and stiffness following the treatment period. While ice showed a moderate advantage over heat in the improvement of symptoms, detailed objective assessments did not reveal a significant difference between the two treatments. During the trial period the range of movement increased and the knees cooled on manual appreciation, the average knee circumference diminished slightly, but radiometer measurements of heat emission did not alter significantly. The fact that 18 of the 0 knees improved to some extent during the trial period with two apparently opposite forms of therapy suggests two possibilities. The first is that surface heating and cooling have similar effects on the knee joint. Although surface heat increases and surface cold decreases blood flow through tissues around the knee joint as shown by venous occlusion plethysmography (Bonney et al., 1951), this does not mean that the blood flow to the bony structures of the knee is similarly changed (Downey, 1964). In fact, Hollander and Horvath (1949) showed that superficial heating reduced knee-joint temperature in rheumatoid arthritis as measured by intra-articular thermometry, while superficial cooling increased it. On the other hand, deep heating (microwave) increased radioactive sodium clearance from the knee joint (Harris and Millard, 1956), presumably as a result of increased blood flow. Superficial cold induces deeper vasodilatation (Murphy, 1960) and so may have a similar effect on the knee joint as the hotpack technique used in this trial. Secondly, it may be that both the ice and heat treatments in themselves exert only a weak influence on the rheumatoid knee, which is obscured by the more important effects of hospital admission, rest, splinting, and an exercise programme. Discrimination between the two treatments may be blurred by the steadily falling baseline of a rheumatoid arthritic patient who has been admitted to hospital. SUMMARY The results of a crossover comparative trial of cold and heat therapy in knees involved with rheumatoid arthritis are reported. Ice applications were acceptable to patients and were associated with a greater relief of pain and stiffness than hot applications. However, objective assessments did not show any measurable difference between the results of the two treatments.

5 4 ANNALS OF PHYSICAL MEDICINE VOL. IX NO. It is suggested that ice packs deserve to be used more widely as a preliminary to exercises for the joints in chronic rheumatoid arthritis. REFERENCES BONNEY, G. L. W., HUGHES, R. A., and JANUS, O. (1951) Clin. Sci., 11, 16. DOWNEY, J. A. (1964)/. Amer.phys. Ther. Ass., 44, 13. HAINES, J. (196) Physiotherapy, 53,. HARRIS, R., and MILLARD, J. B. (1956). Clin. Sci., 15, 9. HOLLANDER, J. L., and HORVATH, S. M. (1949) Amer. J. med. Sci., 18, 543. KNOTT, M. (1964) /. Amer. phys. Ther. Ass., 44, 3.. KUHNS, J. G. (1954) Phys. Ther. Rev., 34, 510. MOORE, D. M. (1964) /. Canad. Arthr. Rheum. Soc,, 1. MURPHY, A. J. (1960) Phys. Ther. Rev., 40, 11. ROPES, M. W., BENNETT, G. A., COBB, S., JACOX, R., and JESSAR, R. A. (1959) Ann. rheum. Dis., 18, 49.