Twelve months after onset of acute low back pain, most are back at work but many remain in pain

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1 Twelve months after onset of acute low back pain, most are back at work but many remain in pain Summary of Schiotz-Christensen B, Nielsen G, Hansen V, Schodt T, Sorensen H and Olesen F (1999): Long-term prognosis of acute low back pain in patients seen in general practice: a 1-year prospective follow-up study. Family Practice 16: [Prepared by Chris Maher, Editorial Board member.] Questions: What is the clinical course of acute low back pain? What clinical information predicts outcome? Design: Inception cohort study with 12-month follow-up. Setting: General practice clinics in Denmark. Patients: Five hundred and twenty-four patients with low back pain (LBP) of < 14 days duration. Pregnancy, LBP in the previous six months, malignancy and vertebral fracture were exclusion criteria. Follow-up was 96 per cent at 12 months. Assessment of prognostic factors: Demographic characteristics, history related to current and past LBP episodes, physical examination and overall assessment by general practitioner (GP). Main outcome measures: Sick leave, ability to manage ordinary daily activities, pain resolution plus global rating of outcome, ie poor, fair, good. Poor outcome was defined as sick leave in last observation period and currently unable to manage ordinary daily activities. Main results: At baseline, 100 per cent of patients had pain, by one month 59 per cent, at six months 56 per cent and at 12 months 46 per cent. Problems in performing daily activities were present in 57 per cent at baseline, 16 per cent at one month, 9 per cent at six months and 8 per cent at 12 months. At baseline, 43 per cent were on sick leave. At one month, 3 per cent were currently on sick leave and 45 per cent had taken sick leave since baseline assessment. At six months, 3 per cent were currently on sick leave and 15 per cent had taken sick leave since last assessment and at 12 months, 2 per cent were currently on sick leave and 14.8 per cent had taken sick leave since last follow-up. At 12 months, poor outcome was noted in 17 per cent. Predictors of poor outcome (expressed as odds ratio with 95 per cent confidence interval) included previous sick leave due to LBP: 2.3 (1.3 to 3.9), disabled by current episode: 2.4 (1.3 to 4.2) assessed by GP as most likely to develop chronic LBP: 10.4 (2.2 to 49.1) Conclusion: The prognosis of acute LBP amongst patients presenting to a GP can look more or less favourable depending upon how recovery is defined. Most patients return to work within one month, but almost half still have pain at one year. The prognosis of acute LBP has traditionally been considered favourable, with reports that 90 per cent recover within two weeks. However, most studies that support this view have limited follow-up, and have assumed that if the patient did not return for review, they had recovered. Recently, Van den Hoogen and co-workers (1998) reported that, while 90 per cent of patients with acute LBP were pain-free at 12-month follow-up, during the 12-month observation period, 76 per cent of patients had a recurrence of their LBP. Croft and co-workers (1998) reported that, at 12-month review, only 25 per cent of patients with acute LBP had completely recovered and had neither pain nor disability. The Schiotz-Christensen study reveals that whilst only a small group of patients remain severely disabled and require sick leave, a larger group remain in pain at 12 months (46 per cent), and re-exacerbation is common (15 per cent). No relationship was found between the treatment intervention and outcome after 12 months The best predictive factor for developing chronic LBP was the GP s impression of the patient s susceptibility to developing chronic LBP. The patient s area of pain, history and physical examination findings had little or no predictive value. This paper is important in that it reveals that acute LBP is not a self-limiting condition as previously reported. Rather, although the risk of developing severe disabling LBP is low, the risk of developing chronic LBP is high. This paper highlights the limitation of sick leave as a sensitive outcome measure in this patient group. It provides a challenge to the physiotherapy profession to develop interventions that can influence the prognosis of LBP and predictive measures to assess its risk. Peter O Sullivan Curtin University of Technology Croft PR, Macfarlane GL, Papageorgiou AC, Thomas E and Silman AJ (1998): Outcome of low back pain in general practice: a prospective study. British Medical Journal 316: Van den Hoogen HJM, Koes BW, van Eijk JM and Deville W (1998): On the course of low back pain in general practice: a one year follow up study. Annals of the Rheumatic Diseases 57: Australian Journal of Physiotherapy 2000 Vol

2 Knee bracing increases thigh muscle atrophy but improves knee function after ACL reconstruction Summary of Risberg MA, Holm I, Steen H, Eriksson J and Ekeland A (1999): The effect of knee bracing after anterior cruciate ligament reconstruction: a prospective randomized study with two years follow up. American Journal of Sports Medicine 27: [Prepared by Rob Herbert, Editorial Board member.] Question: Does knee bracing after anterior cruciate ligament (ACL) reconstruction influence knee joint laxity, lower limb function, thigh muscle atrophy, patient satisfaction or risk of intra-articular injury? Design: Randomised, assessor-blinded trial with two-year follow-up. Subjects: Sixty patients with ACL injury undergoing bonepatellar tendon-bone ACL reconstruction. Intervention: After surgery, subjects in the braced group wore a rehabilitative range of motion brace for two weeks, then a functional knee brace for 10 weeks. Thereafter, the brace was worn as needed for sport. For the first six weeks after surgery, range was restricted to 0 to 90 degrees flexion. Subjects were instructed to wear the brace continuously for eight weeks, then during waking hours for four weeks. Outcomes: The following were measured at various times up to two years post-surgery: antero-posterior laxity measured with an arthrometer; knee function measured on the 100-point Cincinatti Knee Scale; thigh muscle crosssectional area measured with computed tomography; isokinetic and functional muscle strength; activity measured on the Tegner scale; pain; satisfaction; and intra-articular injury identified with magnetic resonance imaging. Results: Fifty-six patients (93 per cent) were followed up. More than two-thirds wore the brace as recommended, but 27 per cent discontinued brace use because of skin irritation or discomfort. Three months after surgery, the braced group had better knee function than controls (mean Cincinatti knee scores of 69.1 and 62.7, respectively; difference = 6.4 points) but reduced thigh muscle cross-sectional area (90.3cm 2 compared with 94.9cm 2 ; difference = 5.1 per cent). There were no statistically significant differences at other times or for other variables. Conclusion: Knee bracing increases thigh atrophy but improves knee function after ACL reconstruction. These effects are transient. This randomised study considered domains of impairment and function over a two-year period. Statistically significant differences were detected at three months. They were transient and reflected the duration of use of the brace. This study may suggest that the brace modulated individuals behaviours (but not activity levels) resulting in increased perceived function at the expense of limb-to-limb muscle symmetry. (The study uses the term atrophy, yet it may also reflect some level of hypertrophy of the contralateral limb). The Cincinatti Knee Scale is sensitive to functional changes during ACL rehabilitation and is associated with pain and muscle strength impairments in individuals not wearing a brace. Therefore it is of interest that the significantly higher subjective knee function in the braced group did not reflect changes in pain and muscle strength. The parallel significant reduction in relative cross-sectional area of the thigh in those individuals with the brace further suggests that wearing the brace may impact on the association between these variables. Although bracing may be considered an external ligament, it is clear that it also impacts on the torque-generating capacity and control of the muscles crossing the joint. Further investigations of lower limb motor control, muscle activity patterns and functional adaptations following surgery with and without bracing may clarify motor control adaptations. The clinician can present the argument that, in the long term, there are no obvious biomechanical and functional advantages or disadvantages for the use of the brace. For some individuals, the subjective increase in function early in rehabilitation may represent a net benefit to adequately compensate for the asymmetry in thigh muscle girth and the logistical problems of wearing a brace correctly and consistently. This may not be the case for others, and represents a subjective judgment for both the clinician and patient. Garry Allison The University of Western Australia 238 Australian Journal of Physiotherapy 2000 Vol. 46

3 Limited/inconclusive evidence for acupuncture treatment of chronic pain Summary of Ezzo J, Berman B, Hadhazy V, Jadad A, Lao L and Singh B (2000): Is acupuncture effective for the treatment of chronic pain? A systematic review. Pain 86: [Prepared by Chris Maher, Editorial Board member.] Question: In patients with chronic pain, is acupuncture more effective than (i) no treatment, (ii) sham acupuncture, (iii) non-acupuncture shams or (iv) standard care? Data sources: Studies were identified by searching Medline ( ), the Cochrane Complementary Medicine Fields trial registry, and the CAMPAIN (Complementary and Alternative Medicine in Pain) registry. Hand searching of conference proceedings and citation tracking was also performed. Data extraction: Two reviewers independently assessed study quality using the Jadad scale. Outcomes were defined as positive when acupuncture was significantly more effective than control, neutral when not significantly different from control and negative when significantly less effective than control. A best evidence synthesis was performed. Main results: Fifty-one trials met the inclusion criteria. Twenty-one trials showed positive effects (acupuncture significantly better than control), three showed negative effects (acupuncture significantly worse than control) and 27 were neutral (no significant difference between groups). Trials receiving a low quality score (34 of 51 trials) were more likely to report positive results (p < 0.05). The five trials that compared acupuncture with no treatment had positive outcomes, but all were of low quality and so provide limited evidence that acupuncture is more effective than no treatment. Because of inconsistent results, there is inconclusive evidence that acupuncture is more effective than sham acupuncture, non-acupuncture shams and standard care. Of the 11 trials comparing acupuncture with a non-acupuncture sham, four were high quality (all neutral) and seven low quality (five positive/two neutral). Of the 22 trials that compared acupuncture with sham acupuncture, 10 were low quality (four positive/10 neutral) and 12 were high quality (three positive/nine neutral). Of the 12 trials comparing acupuncture with standard care, 11 were low quality (two negative/six neutral/three positive) and one high quality (negative). Conclusion: There is limited evidence that acupuncture is more effective than no treatment and inconclusive evidence that it is more effective than sham acupuncture, other shams or standard care. Other systematic reviews of acupuncture for specific musculoskeletal conditions concur that currently available research evidence does not allow us to conclude that acupuncture is, or is not, effective, and high quality trials are rare (eg White and Ernst 1999). Convincing evidence of the efficacy or otherwise of acupuncture for pain relief will only come from well-designed randomised trials with adequate sample sizes and follow-up. Blinding of subjects to group allocation has been a particular problem in acupuncture research, but the development of an apparently credible sham procedure where no skin penetration occurs is a promising development (Streitberger and Kleinihenz 1998). What do the conclusions of this systematic review mean for physiotherapists currently seeking to make the best choice of treatment techniques for relief of chronic pain? The conclusion that there is limited evidence that acupuncture is more effective than no treatment for chronic pain does little to inform practice. The non-specific aspects of the therapeutic interaction mean it is usually true that doing something is better than doing nothing. The finding of inconclusive evidence that acupuncture is more effective than placebo or other treatment is no reason to abandon the use of acupuncture as a safe therapeutic tool with few side effects. In the absence of compelling research evidence, clinicians should continue to rely on their clinical reasoning skills in selecting acupuncture as a suitable treatment technique in individual cases. Goals of treatment, patient preferences and individual response to treatment remain the guiding influences on therapeutic choice in clinical encounters. Treatment goals in chronic pain often include overcoming fear-avoidance behaviours and improving physical functioning, and the use of a passive treatment technique such as acupuncture may not be a logical choice in such cases. Megan Davidson La Trobe University Streitberger K and Kleinhenz J (1998): Introducing a placebo needle into acupuncture research. Lancet 352: White AR and Ernst E (1999): A systematic review of randomized controlled trials of acupuncture for neck pain. Rheumatology 38: Australian Journal of Physiotherapy 2000 Vol

4 Electrical stimulation prevents subluxation and associated pain when applied soon after stroke Summary of Linn SL, Granat MH and Lees KR (1999): Prevention of shoulder subluxation after stroke with electrical stimulation. Stroke 30: [Prepared by Rob Herbert, Editorial Board member.] Question: Does electrical stimulation applied soon after stroke prevent shoulder subluxation, pain and impaired motor function? Design: Randomised assessor-blinded trial with eight week follow-up. Subjects: Forty patients who had a stroke in the preceding 48 hours, with upper limb manual muscle test grades of 2, capable of communicating pain scores, and without a history of shoulder pathology. Intervention: Subjects in the stimulation group received four weeks of electrical stimulation to the supraspinatus and posterior deltoid muscles through a single pair of surface electrodes for four sessions each day. The length of each session was progressed from 30 minutes in the first week to 60 minutes in the fourth week. Stimulation consisted of asymmetrical biphasic pulses, with pulse width of 300 µs delivered at a frequency of 30 Hz. The duty cycle was 15 seconds on and 15 seconds off. Intensity of stimulation was adjusted to produce the desired movement at a tolerable level (communication with authors July 2000). Both groups received conventional physiotherapy and occupational therapy. Outcomes: Outcomes were measured at four and 12 weeks. Subluxation was assessed with a single antero-posterior radiograph, and was rated on a 5 point scale (0 = normal, 4 = [complete] dislocation) and measured in millimetres. Pain was assessed as pain-free lateral rotation range of motion and, on a five-point scale, motor function was measured with the upper limb section of the Motor Assessment Scale. Upper limb girth was measured with a tape measure. Results: Subjects in both groups experienced subluxation and pain over the fourweek intervention period. At four weeks, 14 of the 40 subjects (35 per cent) had developed subluxation, and 17 (43 per cent) had shoulder pain. Subluxation and pain were significantly less in the stimulated group than in the control group (mean subluxation scores of 0.3 and 0.8 respectively; mean subluxation 2.3 mm and 6.3mm respectively; mean loss of pain-free lateral rotation 6.5 degrees and 14.8 degrees respectively). Over the subsequent eight weeks, when neither group was stimulated, the stimulation group experienced further subluxation and increases in pain but the control group did not, so that at 12 weeks, the degree of subluxation and pain in the two groups was similar. There were no differences between groups in terms of pain, motor function or upper limb girth. No subject with a Motor Assessment Scale upper limb score of 2 developed subluxation. Conclusion: Electrical stimulation prevents subluxation and associated pain when applied soon after stroke. This article raises several clinical questions. Firstly, the treatment size following the intervention phase was small: 4.1mm subluxation and 8 degrees passive external rotation. The relevance of this to the patient is not apparent, as there were no group differences for verbal pain rating and Motor Assessment Scale scores during the study. Secondly, there was no sustained benefit once the stimulation was withdrawn. At three months post-stroke, there were no group differences in any outcomes measured. This differs from two similar studies (Chantraine et al 1999, Faghri et al 1994) that reported persistent group differences in reduction of pain and subluxation and improved active control after cessation of the stimulation. These two studies recruited sub-acute hemiplegic subjects, used similar stimulation parameters and had longer treatment duration. However, caution is needed in interpreting the Faghri and Chantraine studies, due to potential methodological flaws. Both experimental groups received conventional physiotherapy. No details are supplied as to the frequency and type of therapy, or whether stimulation was integrated into the therapy program. Potentially, motor re-training strategies to augment the short-term effects of stimulation may improve carry-over, but this is yet to be investigated. Thirdly, whilst neither group used shoulder slings, the stimulation group had less reduction in passive shoulder external range. Although this did not reach statistical significance, the treatment effect reported may be clinically worthwhile. Stimulation as a neuroprosthesis offers a potential alternative to immobilising shoulder supports, and the consequential loss of shoulder external rotation range and shoulder pain (Bohannon 1988). Other authors have discussed the potential benefits of functional electrical stimulation. A meta-analysis performed by Glanz and colleagues (1996) demonstrated a significant improvement in force production in favour of electrical stimulation in stroke participants. However, no studies pertained to the shoulder, and the subjects had greater muscle force-producing capabilities than those recruited in the Linn article. In summary, stimulation has potential as an alternative to slings, and as a means of improving force production. Carry-over following removal of stimulation is not guaranteed but may be augmented by motor retraining strategies. The parameters suggested are 30 Hz two to eight 240 Australian Journal of Physiotherapy 2000 Vol. 46

5 hours a day, for longer than four weeks. Further investigation using disability outcomes is warranted. Jannette Blennerhassett Royal Talbot Rehabilitation Centre Bohannon RW (1988): Relationship between shoulder pain and selected variables in patients with hemiplegia. Clinical Rehabilitation 2: Chantraine A, Baribeault A, Uebelhart D and Gremion G (1999): Shoulder pain and dysfunction in hemiplegia: effects of functional electrical stimulation. Archives of Physical Medicine and Rehabilitation 80: Faghri PD, Rodgers MM, Glaser RM, Bors JG, Ho C and Akuthota P (1994): The effects of functional electrical stimulation on shoulder subluxation, arm function recovery, and shoulder pain in hemiplegic stroke patients. Archives of Physical Medicine and Rehabilitation 75: Glanz M, Klawansky S, Stason W, Berkey C and Chalmers TC (1996): Functional electrostimulation in post stroke rehabilitation: a meta-analysis of randomised controlled trials. Archives of Physical Medicine and Rehabilitation 77: