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Course and prognosis of elbow complaints: a cohort study in general practiceS D M Bot, J M van der Waal, C B Terwee, D A W M van der Windt, L M Bouter,J Dekker. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ann Rheum Dis 2005;64:1331–1336. doi: 10.1136/ard.2004.030320 Objective: To describe the course of new episodes of elbow complaints in general practice, and to identifypredictors of short term and long term outcome in terms of pain intensity and functional disability.
Methods: 181 patients with elbow complaints filled in questionnaires at baseline and at 3, 6, and 12months of follow up. Baseline scores of pain and disability, characteristics of the complaint, sociodemographic and psychosocial factors, physical activity, general health, and comorbidity were . . . . . . . . . . . . . . . . . . . . . . .
investigated as possible predictors of outcome. Outcome measures were analysed separately usingmultiple regression analyses.
Results: 13% of the patients reported recovery at the 3 month follow up and 34% at 12 months. Irrespective of outcome and length of follow up, a longer duration of the complaint before consulting the general practitioner, having musculoskeletal comorbidity, and using ‘‘retreating’’ as coping style increased the likelihood of an unfavourable outcome. Less social support was associated with an unfavourable outcome at 3 months, and having a history of elbow complaints and using ‘‘worrying’’ as coping style were associated with an unfavourable outcome at 12 months. The explained variance of the models ranged from 46% to 49%.
Conclusions: Recovery of patients with elbow complaints in general practice was poor. Besides Accepted 2 February 2005Published Online First characteristic of the complaint, passive coping and less social support were related to a worse prognosis.
The results of this study may help general practitioners to provide patients with more accurate information . . . . . . . . . . . . . . . . . . . . . . .
Elbow pain and associated disability are common, and supportingeneral,althoughthesefactorswerefoundtobe affected individuals often consult their general practi- related to a high risk of chronicity in patients consulting their tioner (GP). Data of the second Dutch national survey of GPs for low back pain12 13 or neck and shoulder complaints.
general practice1 2 showed that the incidence of elbow Knowledge of predictors of outcome should lead to the early complaints was around 7.2 per 1000 patients per year.3 identification of those at risk for the development of chronic Elbow complaints seldom occur on their own.4 Many patients report additional symptoms in the neck, shoulder, arm, or Our objectives in this study were to describe the course of hand.4 These complaints can be a considerable burden to both new episodes of elbow complaints in adults in general patient and society, owing to inability to work, loss of practice, and to identify predictors associated with short term productivity, and difficulty in carrying out household and long term outcome in terms of pain intensity and Individual characteristics and (work related) physical and psychosocial factors have been identified as risk factors for the onset of elbow complaints.7–9 These factors may also act as putative prognostic factors for persistent pain and disability.
A large observational cohort study was conducted in 61 Not much is known about the prognosis of elbow complaints general practices (97 GPs).14 Forty nine of the GPs partici- after presentation in general practice. The vast majority of pated in the second Dutch national survey of general practice research on such complaints has been specifically aimed at (NS2), carried out by the Netherlands Institute of Primary lateral elbow pain (that is, lateral epicondylitis, tennis elbow, Health Care (NIVEL) in 2001.1 2 GPs recruited patients with a or extensor carpi radialis tendinitis).10 Hudak et al reviewed new episode of a complaint at the neck, shoulder, elbow, published reports on the clinical course of lateral elbow pain wrist, or hand. An episode was considered to be ‘‘new’’ if and prognostic factors for outcome. Only four of 40 studies patients had not visited their GP for the same complaint provided at least moderate strength of evidence, showing that during the preceding three months. Inclusion criteria were the site of the lesion and previous occurrence predicted age 18 years or older and being capable of filling in Dutch outcome.10 We found only one additional prognostic study of questionnaires. Patients were excluded if the presented outcome in elbow complaints carried out in general practice,11 symptoms were caused by a fracture, malignancy, prosthesis, which showed that high physical strain at work, being amputation, or congenital defect, or if the patient was employed in manual jobs, high baseline level of distress, a pregnant. In all, 638 patients (88%) who consulted their GP high level of pain at baseline, and a complaint on the with a complaint at the neck or upper extremity complaints dominant side were related to a poor outcome of lateralepicondylitis at one year follow up. So far, little attention has Abbreviations: ACSM, American College of Sports Medicine; MIC, been paid to the potential prognostic value of psychosocial minimum important change; PCI, pain coping inventory; QoL, quality of factors, such as coping with pain, kinesiophobia, and social life; SF-36, 36 item short form health survey Table 1 Patient characteristics at baseline (n = 181) *Value are mean (SD) for continuous scales or n.
ÀPatients with concomitant neck, shoulder, arm, hand, or wrist `Asthma, diabetes, cardiovascular diseases, cancer, psychological ôACSM, American College of Sports Medicine.18 Baseline scores outcome measuresPain intensity (scale 0–10) as the primary complaint returned the baseline question- naire. Of these, 181 reported elbow complaints (either as aprimary of secondary complaint) and were included in the study. Follow up questionnaires were sent after three, six, The informed consent procedure and protocol were approved by the medical ethics committee of the VU University Medical Centre. Written informed consent was Perceived recovery was measured by asking patients if their complaint still bothered them. Patients that responded ‘‘no’’ were regarded as recovered. Other outcome measures were change in pain intensity and change in functional disability at the three months follow up (short term) and the 12 months follow up (long term). The intensity of the current pain (pain during the previous 24 hours) was measured on an 11 point numerical scale ranging from 0 (no pain) to 10 (unbearable pain). Functional disability was measured with the modified pain free function index, a 10 item elbow specific scale measuring difficulty with the performance of common daily activities,15 scores ranging from 0 (not disabled) to 100 (completely disabled). Changes in pain intensity and functional disability were calculated by subtracting the scores at three months and 12 months from Putative predictorsWe distinguished seven categories of putative predictors Comorbidity (musculoskeletal)No comorbidity N Sociodemographic factors: age, sex, body mass index (calcu- lated from self reported weight and height), right/left handedness, marital status, smoking behaviour, and N Characteristics of the complaint: duration of the current episode, presumed cause of the complaint, history of elbow complaints, involvement of one or both elbows, complaint at the dominant arm, frequency of discomfort by the complaint, symptoms (for example, tingling in hand/fingers, loss of strength), and the use of analgesics.
N Comorbidity: list of concomitant musculoskeletal com- plaints, and a list of complaints and diseases other than N Physical activity: We measured whether patients met the norm for healthy activity (yes or no), which recommends that all adults should have 30 minutes or more of moderate intensity physical activity on at least five days of the week,16 17 and whether they met the American College of Sports Medicine (ACSM) position stand (yes orno), which recommends carrying out heavy physicalexercise or sports at least three times a week.18 N Psychosocial factors: Distress was measured by the shortened version of the distress scale of the four dimensional symptom questionnaire,19 20 on which a higher score indicates more distress. Coping was measured with the pain coping inventory (PCI),21 22 consisting of six scales: pain transformation, distraction, reducing demands, retreating, worrying, and resting, a higher score indicating more use of the strategy concerned. Kinesiophobia was measured using two subscales (‘‘fear avoidance beliefs’’ and ‘‘importance of exercise’’), derived from the Tampa scale23 24 and the fear avoidance and beliefs question- naire,25 with a higher score indicating more fear avoidance and finding exercise more important. Social support was measured with the social support scale26 on which a higherscore indicates less social support.
Figure 1 Percentage of recovery in patients with elbow complaints after N General health: vitality was measured by the vitality three, six, and 12 months of follow up.
subscale from the 36 item short form health survey (SF-36)27; perceived general health was measured with the first investigated in a multiple regression model. Age, sex, pain question of the general health perceptions subscale of the intensity, disability, and duration of the complaint were SF-3627; and perceived overall quality of life (QoL) was included in all multiple regression models independent of the measured on a five point rating scale with response p value. All factors were entered simultaneously in a multiple options ‘‘bad,’’ ‘‘moderate,’’ ‘‘good,’’ ‘‘very good,’’ or linear regression model. If the number of putative predictors ‘‘excellent.’’ Higher scores indicate more vitality, better to be entered in the model exceeded n/10, the factors were perceived health. and better quality of life.
entered in blocks (sociodemographic factors first, character-istics of the complaints next, and the remaining factors last).
A manual backward selection procedure was used to sequentially exclude factors and retain only factors with a p Univariate regression analyses were undertaken to examine value of ,0.10 (Wald statistic) in the final model, which the relation between each of the putative predictors and could be regarded as independent predictors of outcome. The changes in pain and functioning at the three month and the percentage of explained variance (R2) was calculated to give 12 month follow up. Predictors of recovery could not be an indication of the predictive power of the final models.
studied because of lack of power (only 20 and 51 patients,respectively, were recovered at follow up). Factors that were non-linearly related to the outcome were either dichotomised Baseline characteristics of the 181 patients are shown in or divided into tertiles (low, medium, high), with the low table 1. The mean (SD) pain intensity score at baseline was category as the reference category. Putative predictors 5.3 (2.1) and the mean disability score was 34.6 (20.4); 54% that were associated with the outcome (p,0.20) were of the patients reported having had the complaint before in Table 2 Predictors of change in pain intensity at three months (R2 = 0.46) and 12 months (R2 = 0.47): results of the multiplelinear regression analyses Baseline scoreMore severe pain (per point increase) Characteristics of complaintDuration of current episode: Complaint at dominant side (v other side) Tendency to massage hands (v no tendency) ComorbidityNo musculoskeletal comorbidity (v comorbidity) Multiple musculoskeletal complaints (v ‘‘no’’) Psychosocial factorsCoping: more retreating (per point increase) Coping: more worrying (per point increase) *b positive: favourable change in pain intensity since baseline per unit of the independent predictor; b negative: unfavourable change in pain intensity sincebaseline per unit of the independent predictor.
ÀHigher score means less social support.
b, regression coefficient; CI, confidence interval.
the previous year (that is, there was a history of the months (table 2). A worse outcome at three months was predicted by being female, higher age, a longer duration of In all, 158 patients (87%) completed the three months the complaint at presentation, having multiple additional follow up questionnaire, and 152 patients (84%) completed musculoskeletal complaints, using retreating as a coping the 12 month questionnaire. There were no significant strategy, and having less social support. For example, the differences between responders and dropouts in age, sex, improvement in pain intensity at three months for a women functional disability, and pain intensity.
(20.94) who had the complaint more than six months(22.19) was 3.13 points less than for a man who had the complaint for less than one week, provided that the other After three months, 20 patients (13%) reported recovery, and predictors of the model were similar.
51 patients (34%) reported recovery after 12 months (fig 1).
Predictors of a poorer outcome at 12 months were less pain Of the patients who were not fully recovered at three months, at baseline, a longer duration of the complaint at presenta- 24% reported substantial improvement and 37% reported tion, having had the complaint before, having a tendency to some improvement compared with baseline. At 12 months, massage your hands, having multiple musculoskeletal 21% of patients without full recovery reported substantial complaints, and scoring high on retreating and worrying improvement and 25% some improvement. At follow up the (table 2). The explained variance was 0.46 at the three mean (SD) reduction in pain intensity was 1.3 (2.3) points at months follow up and 0.47 at 12 months.
three months and 2.1 (2.6) points at 12 months (p,0.01).
The mean reduction in disability was 6.3 (16.2) points at Predictors of outcome: functional disability three months and 11.9 (21.2) points at 12 months (p,0.01).
Being employed, being more disabled at baseline, and havingan accident as the presumed cause of the complaint were Predictors of outcome: univariate analysis independently associated with a better outcome at three The results of the univariate regression analyses showing the months (table 3). Factors that predicted a worse outcome associations between the putative predictors and change in were: having children in the household, more intense pain at pain intensity and change in functional disability after three baseline, a longer duration of the complaint at presentation, or 12 months are presented in the appendix (the appendix having multiple musculoskeletal complaints, a high score on can be viewed on the journal website at www.annrheumdis.
the pain coping scale ‘‘retreating,’’ and less social support.
com/supplemental). Age, a history of elbow complaints, Being less disabled at baseline, having more intense pain at having additional musculoskeletal complaints, using the baseline, a longer duration of the complaint at presentation, coping strategy ‘‘retreating’’, and social support were chronic disease as the presumed cause of the complaint, associated with both outcomes at both follow up periods.
additional complaints at the hip or knee, and a higher scoreon the pain coping scales ‘‘retreating’’ and ‘‘worrying’’ were significantly associated with a worse outcome at 12 months More intense pain at baseline, having a complaint in the (table 3). The explained variance of the models for change in dominant arm, and a higher score on the fear avoidance scale functional disability was 0.49 at three months and 0.47 at 12 were significantly associated with a better outcome at three Table 3 Predictors of change in disability at three months (R2 = 0.49) and 12 months (R2 = 0.47): results of the multiple linearregression analyses Sociodemographic factorsEmployed (v unemployed) Baseline scoreMore severe pain (per point increase) Characteristics of complaintDuration of current episode: Putative cause: accident (v ‘‘no’’) Putative cause: chronic disease (v ‘‘no’’) ComorbidityComplaints at hip/knee (v ‘‘no’’) Multiple musculoskeletal complaints (v ‘‘no’’) Psychosocial factorsCoping: more retreating (per point increase) *b positive: favourable change in disability since baseline per unit of the independent predictor; b negative: unfavourable change in disability since baseline perunit of the independent predictor.
ÀHigher score means less social support.
b, regression coefficient; CI, confidence interval.
We may have missed some predictors of short and long We have described the course of elbow complaints in general term elbow complaints or that we may have found some practice and examined potential predictors of outcome. Only associations by chance. Treatment could be an important 13% of reported full recovery after three months and just one predictor of outcome.29 In the study by Hay et al the recovery third of the patients recovered after one year of follow up. These rate after four weeks differed substantially between treat- figures are consistent with those of Hay et al, who reported a ment groups (4% to 42%).28 In everyday clinical practice low overall recovery rate (17%) after four weeks in primary care decisions to treat are often dependent on indicators of patients with lateral epicondylitis.28 Other studies have used prognosis, such as the duration or severity of symptoms. Thus general improvement as outcome measures instead of complete differences in outcome are not only related to the treatment recovery and have found percentages of 69–85% after one given but also to differences in the severity of the condition.
year.11 29 In our study 90% of all patients reported at least some Consequently, interpretation of the predictive value of improvement after one year of follow up. The mean reduction treatment variables is very difficult in observational research, in pain intensity was 1.3 (2.3) points at three months and 2.1 as this information cannot be interpreted as evidence for the (2.6) points at 12 months. In clinical practice this may be effectiveness of treatment. We therefore decided not to considered to be meaningful: research has shown that a include treatment variables in our prognostic model. In reduction of one point on a 0–10 point scale represents the addition, we did not included work related factors, because minimum clinically important change in pain intensity more than one third of the study population did not have (MIC).30 31 The mean reduction in disability score was 6.3 (16.2) points at three months and 11.9 (21.2) points at 12 Lateral epicondylitis is the most common problem among months. The MIC of this functional disability scale is unknown.
patients with elbow complaints. The Dutch general practice However, in most circumstances the MIC appears to be guidelines recommend a wait and see policy for epicondylitis; approximately half a standard deviation.32 In this case, half a injections or physiotherapy are only recommended in standard deviation would be approximately 10 points, which patients with persistent and severe pain or disability.42 means that the observed changes in functional disability were Although we have no information how well GPs adhere to only clinically important after 12 months of follow up.
these guidelines, we assume that in most cases the initial Irrespective of outcome measure and length of follow up, a treatment will be based on an expectant policy, which worse prognosis was found for patients who had a longer includes time limited prescription of drugs and recommenda- duration of their complaint at baseline. This is in agreement tions for temporarily avoiding pain provoking activities. Our with studies on the prognosis of musculoskeletal complaints results offer additional evidence on the prognostic value of in the neck or shoulder.33–35 Not surprisingly pain intensity coping and social support, which may be relevant to future and functional disability at baseline were strongly associated updates of the guidelines. However, owing to the observa- with changes in these outcomes at follow up. Having more tional design of our study, our results provide only pain or disability at baseline leaves more room for a large preliminary evidence for a causal association between the reduction at follow up, but does not necessarily result in a predictors found and changes in pain and functional better prognosis, as these patients may still have considerable disability in elbow complaints. The predictive capability of pain or disability at follow up. For instance, a patient with a the model should be assessed in another population of baseline pain score of 9 and a follow up score of 6 improved more than a patient with a baseline score of 3 and a follow up Our study suggests that few patients who consult their GP score of 1. This may also explain why a higher pain score at with a new episode of an elbow complaint have full recovery baseline predicted a poorer functional disability at follow up.
of their symptoms, though 90% of all patients reported at Having had elbow complaints in the past predicted a worse least some improvement after one year of follow up. The outcome at long term follow up. This is similar to the results average pain and disability scores diminished after three and 12 months, although the improvement in disability can only The passive coping styles retreating (for example, ‘‘make be considered important after 12 months. Several factorswere found to be independent predictors of outcome. As well sure that I don’t get upset’’; ‘‘separate myself’’) and worrying as the characteristic of the complaint (for example, duration, (‘‘focus on pain all the time’’; ‘‘I think the pain will get history of complaints), passive coping and less social support worse’’) independently predicted poorer outcome. Passive were related to a worse prognosis. The results of our study coping strategies are thought to generate a preoccupation may help GPs to identify patients at risk for the development with bodily symptoms, which in turn may increase the of chronic complaints and provide them with more accurate sensation of pain and disability.36 37 Several studies have information on their prognosis. More high quality studies in found that a passive coping strategy is associated with a poor general practice are needed to confirm our results.
outcome in neck and back pain,12 38 and in patients withrheumatoid arthritis.36 39 40 Less social support was associated with worse short term This study is financially supported by the Dutch Arthritis Association.
outcome in our study. Low levels of social support at the timeof diagnosis predicted pain and functional disability inpatients with rheumatoid arthritis at long term follow The electronic supplementary appendix can be found up.37 41 Social resources may affect the health status of on the journal web site, www.annrheumdis.com/ patients by enhancing the ability of an individual to copewith the stress of their disease.
In contrast to the results of Haahr and Anderson,11 we found an association between sex and age and pain at three . . . . . . . . . . . . . . . . . . . . .
months follow up. Furthermore, they found that lateral S D M Bot, J M van der Waal, C B Terwee, L M Bouter, Institute for epicondylitis at the dominant side predicted a worse Research in Extramural Medicine, VU University Medical Centre, prognosis at 12 months, while in our study it predicted a favourable outcome at three months. As well as a difference D A W M van der Windt, Department of General Practice, VU University in study population (we studied patients with a variety of elbow complaints), it is possible that the difference in the J Dekker, Department of Rehabilitation Medicine, VU University Medical follow up period may explain these contrasting findings.
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