Ferran Pellisé

Pain measurement in patients with low back pain

Pain is a multidimensional experience that is a prominent feature of many musculoskeletal disorders. Despite its subjective nature, pain is a highly relevant complaint; hence, nothing should deter physicians from attempting to formally assess it. This Review summarizes the main aspects of pain measurement from a practical standpoint, with a specific focus on low back pain. On balance, for the assessment of pain intensity, categorical scales with verbal descriptors or numerical rating scales seem to be preferable to traditional visual analogue scales, although no single best measure can be recommended. Pain per se should be assessed, rather than surrogate measures such as analgesic use. Back and leg pain should be evaluated separately in patients in whom these conditions coexist. For assessing change, prospective measurements are preferable to retrospective reports. Pain is not synonymous with function or quality of life, and other tools covering these important outcome dimensions should complement the assessment of pain, especially in patients with chronic symptoms. Clinicians should be aware of the psychometric properties of the tool to be used, including its level of imprecision (random measurement error) and its minimum clinically important difference (score difference indicating meaningful change in clinical status).

A critical review of guidelines for low back pain treatment

Main problem: Little is known about the methodological quality of guidelines for low back pain treatment. We evaluated the methods used by the developers according to established standards. Methods: PubMed, guideline databases, and the World Wide Web were used to identify guidelines. Seventeen guidelines met the inclusion criteria: interventions for low back pain stated, recommendations based on or explicitly linked to evidence, and English version available. Guidelines were evaluated independently by two appraisers using a practical tool for this purpose, Users’ Guides to the Medical Literature, and the Appraisal of Guidelines for Research and Evaluation (AGREE) instrument. Results: Thirteen guidelines (76%) specified the most important therapies applied, but only nine (53%) included a complete description of the target population. Explicit processes to identify, select, and combine evidence were described in only six guidelines (35%). Few guidelines (3; 18%) explicitly considered all main outcomes when formulating therapeutic recommendations, and none contained a process to determine the relative value of different outcomes. Methodological criteria for grading the strength of the recommendations varied, and were often insufficiently specified. None of the guidelines assessed the impact of uncertainty associated with the evidence and values used. According to AGREE the quality score was highest for the scope and purpose, and clarity and presentation domains, and lowest for editorial independence and applicability. With regard to the recommendations, there was consensus for some of the interventions for acute pain (analgesics and NSAIDs, maintaining physical activity, and avoiding excessive bed rest), but explicit recommendations were lacking or ambiguous for 41% of the interventions. Most of the guidelines did not contemplate specific recommendations for chronic pain. Conclusions: A small number of the available guidelines for low back pain treatment achieved acceptable results for specific quality criteria. In general, the methods to develop the guidelines’ therapeutic recommendations need to be more rigorous, more explicit and better explained. In addition, greater importance should be placed on the recommendations for chronic pain.

Prevalence of Low Back Pain and Its Effect on Health-Related Quality of Life in Adolescents

OBJECTIVES To assess the prevalence of low back pain (LBP) in adolescents and the clinical features of LBP in 2 European countries and to evaluate the effect of LBP on health-related quality of life (HRQOL) using standardized validated generic and disease-specific instruments. DESIGN Cross-sectional study. SETTING Secondary schools of Barcelona, Spain, and Fribourg, Switzerland. PARTICIPANTS Representative sample of adolescents from the 2 cities. Intervention Selected adolescents completed a questionnaire including a generic HRQOL (KIDSCREEN-52) and 2 LBP-specific instruments. MAIN OUTCOME MEASURES Results of KIDSCREEN-52, the Roland-Morris Disability Questionnaire, and the Hanover Functional Ability Questionnaire. RESULTS A total of 1470 adolescents (52.6% male) with a mean (SD) age of 15.05 (1.17) years completed the questionnaires (response rate, 85.1%). Low back pain was reported by 587 adolescents (39.8%): isolated LBP in 250 (42.6%), LBP plus other pain in 271(46.2%), LBP plus whole-body pain in 50 (8.5%, and unclassifiable LBP in 16 (2.7%). Five hundred adolescents (34.7%) reported no pain, and 369 (25.6%) reported other pain without LBP. In those with isolated LBP, the percentage of adolescent boys was higher (54.6%; P < .001) and the LBP was mildest. In those with LBP plus whole-body pain, the percentage of adolescent girls was higher (62%; P < .001) and LBP was most severe. All KIDSCREEN scores in the group with LBP plus whole-body pain were significantly lower than in the other groups (effect size, 0.52-1.24). No differences were found between the groups who reported isolated pain, no pain, or other pain with no LBP. On the LBP-specific instruments, adolescents who reported LBP plus other pain had significantly poorer scores (P < .001) compared with those with isolated LBP but better scores (P < .001) than those with LBP plus whole-body pain. CONCLUSIONS Low back pain in adolescents is a prevalent symptom with overall low associated disability and little effect on health-related quality of life. A subset of adolescents in whom LBP is associated with whole-body pain report significant impairment and deserve more attention.

Validation of a minimum outcome core set in the evaluation of patients with back pain

Study Design. Prospective study of patients with subacute osteoporotic fracture (SOF) or chronic low back pain (CLBP). Objective. To evaluate reliability, validity, and responsiveness of a purposefully brief outcome instrument. Summary of Background Data. A minimum standardized “core set” was proposed for monitoring patients with low back pain in 1998, but an assessment of metric properties was still lacking. Methods. The Core Set, SF-36, and Oswestry questionnaires were completed by 154 patients. Test–retest reproducibility was evaluated in a subsample of 43 stable patients with CLBP. Responsiveness was evaluated by estimating effect size (ES) of pre-postsurgery changes in 50 patients with SOF and 23 with CLBP. Results. The total Core Set showed good reproducibility with intraclass correlation coefficients on test–retest near the highest standard of 0.9, whereas internal consistency differed between patients with CLBP and those with SOF (Cronbach’s alpha of 0.92 and 0.64, respectively). Most correlations of the Core Set with SF-36 and Oswestry, previously hypothesized as high, were >0.65, demonstrating good construct validity. Sensitivity to change of the Core Set (ES 0.4–2.3) is similar to the Oswestry (ES 0.7 and 2.3). Conclusions. These findings support the potential usefulness of the Core Set when respondent burden is a major concern. However, subscale scores need to be further tested in other populations before they can be widely recommended.

Radiologic Assessment of All Unfused Lumbar Segments 7.5 Years After Instrumented Posterior Spinal Fusion

Study Design. Prospective observational single-cohort study. Objective. To analyze long-term radiographic changes in all unfused lumbar segments after instrumented posterolateral lumbar fusion. Summary of Background Data. Adjacent segment degeneration (ASD) after lumbar fusion may be a consequence of biomechanical stress or result from constitutional factors. Most studies analyzing ASD only investigate the motion segments immediately above and below the fusion. None compares adjacent segments to all the other unfused segments after instrumented posterior fusion. Methods. Using the distortion-compensated roentgen analysis method, disc height, dorsoventral displacement, and lordosis were measured in 212 unfused segments from 62 patients, on digitized standing radiographs taken before fusion surgery and after a mean follow-up of 7.5 years (range, 4–11 years). The effect of covariables, such as age, length of follow-up, fusion level, number of fused segments, and sagittal and spinopelvic parameters on the preoperative to follow-up changes, were analyzed using a repeated-measurement model. Results. No changes were observed at the segments located below the fusion. All the unfused segments above the fusion showed the same significant loss of disc height. Loss of disc height did not depend on fusion parameters, correlated weakly with age and length of follow-up, and correlated highly across adjacent unfused segments. Conclusions. After posterior lumbar instrumented fusion, radiographic changes suggesting disc degeneration appear homogeneously at several levels cephalad to fusion and seem to be determined by individual characteristics.

Magnetic resonance anatomic study of iliocava junction and left iliac vein positions related to L5-S1 disc.

STUDY DESIGN An in vivo anatomic study analyzing the venous anatomy in the lumbosacral area was performed. OBJECTIVES To obtain in vivo data concerning iliocava junction and left common iliac vein positions at L5-S1. SUMMARY OF BACKGROUND DATA The left common iliac vein and the iliocava junction are at risk during L5-S1 anterior lumbar interbody fusion. Anatomic studies have demonstrated great interindividual variability in this vascular anatomy. METHODS Magnetic resonance angiography was used to study 134 patients. Image processing was carried out with maximum intensity projection algorithm and the maximum intensity projection and addition algorithm. Iliocava junction position was measured in the maximum intensity projection and addition image. Four groups of junction position were established: very high, high, low, and very low. The left common iliac vein position was measured in axial magnetic resonance images, and three groups were established: lateral, intermediate, and medial. To describe the operative window delimited by the venous structures at L5-S1, the study population was classified into 12 configurations by combining junction position and vein position values. RESULTS Very high lateral included 3.76% of the patients, high lateral 48.12%, high intermediate 10.53%, high medial 0.75%, low lateral 15.04%, low intermediate 4.51%, low medial 6.77%, very low lateral 0.75%, very low intermediate 2.26%, and very low medial 7.52%. Medial vein position was significantly more frequent in men. CONCLUSIONS In 18.05% of the study population, the venous structures overlapped the center of the L5-S1 disc, reducing the operative window.

Low Fusion Rate After L5-S1 Laparoscopic Anterior Lumbar Interbody Fusion Using Twin Stand-Alone Carbon Fiber Cages

Study Design. Prospective study of a cohort of patients who underwent L5–S1 laparoscopic anterior lumbar interbody fusion. Objectives. To assess the fusion rate and the clinical outcome more than 2 years after L5–S1 laparoscopic anterior lumbar interbody fusion using twin stand-alone carbon-fiber cages. Summary of Background Data. The first reports on laparoscopic anterior lumbar interbody fusion using stand-alone cages appeared in 1995. Since then several articles have reported contradictory data regarding fusion rate. There are no publications describing the fusion rate of stand-alone lumbar carbon-fiber cages. Methods. The authors evaluated 12 patients (mean age 36.5 years) in whom endoscopic L5–S1 anterior lumbar interbody fusion was performed using twin stand-alone laparoscopic carbon-fiber cages. Clinical evaluation was carried out prospectively by the use of three self-evaluation scales. Radiologic evaluation was performed by an independent radiologist using dynamic flexion–extension films and CT scans at 6 and 12 months after surgery and subsequently every year until fusion was demonstrated. Results. After a mean follow-up of 36.6 months (range 24–63 months) the clinical condition of the patients was significantly better than their preoperative status: visual analog scale (P < 0.01), Prolo score (P < 0.05), and Waddell Disability Index (P < 0.01). L5–S1 mobility did not exceed 5° in any dynamic study. However, the overall CT scan fusion rate at 2 years of follow-up was 16.6%. Three years after surgery, CT demonstrated fusion in one of five patients. Conclusion. Two years after endoscopic L5–S1 anterior lumbar interbody fusion using twin stand-alone laparoscopic carbon-fiber cages, the fusion rate was unacceptably low. However, the clinical outcomes of these patients were significantly improved compared with their preoperative status.

Patient information and education with modern media: the Spine Society of Europe Patient Line

The role of the patient as an active partner in health care, and not just a passive object of diagnostic testing and medical treatment, is widely accepted. Providing information to patients is considered a crucial issue and the central focus in patient educational activities. It is necessary to educate patients on the nature of the outcomes and the benefits and risks of the procedures to involve them in the decision-making process and enable them to achieve fully informed consent. Information materials must contain scientifically reliable information and be presented in a form that is acceptable and useful to patients. Given the mismatch between public beliefs and current evidence, strategies for changing the public perceptions are required. Traditional patient education programmes have to face the potential barriers of storage, access problems and the need to keep content materials up to date. A computer-based resource provides many advantages, including “just-in-time” availability and a private learning environment. The use of the Internet for patient information needs will continue to expand as Internet access becomes readily available. However, the problem is no longer in finding information, but in assessing the credibility and validity of it. Health Web sites should provide health information that is secure and trustworthy. The large majority of the Web sites providing information related to spinal disorders are of limited and poor quality. Patient Line (PL), a patient information section in the Web site of Eurospine, was born in 2005 to offer patients and the general population the accumulated expertise represented by the members of the society and provide up-to-date information related to spinal disorders. In areas where evidence is scarce, Patient Line provides a real-time opinion of the EuroSpine membership. The published data reflect the pragmatic and the common sense range of treatments offered by the Eurospine membership. The first chapters have been dedicated to sciatica, scoliosis, cervical pain syndromes, low back pain and motion preservation surgery. Since 2008, the information has been available in English, German, French and Spanish. The goal is for Patient Line to become THE European patient information Web site on spinal disorders, providing reliable and updated best practice and evidence-based information where the evidence exists.

Preoperative erythropoietin in spine surgery

Spine surgery may be associated with profuse intraoperative bleeding that often requires blood transfusions. In recent years several techniques have been developed to avoid allogenic transfusions and their potential complications to surgical patients. In this study we review and analyse the role of preoperative recombinant human erythropoietin (rHuEPO) administration in spine surgery as a blood conservation strategy. Between 1998 and 2002, a total of 250 patients scheduled for spine surgery were included in our blood-sparing program: 114 patients (group 1), operated on before rHuEPO approval (2000), underwent preoperative autologous blood donation (ABD) alone, and 136 patients operated on after rHuEPO approval (groups 2 and 3) received rHuEPO while undergoing ABD. Adding rHuEPO to ABD resulted in higher haemoglobin and haematocrit values the day of surgery, more ABD units retrieved per patient and, consequently, reduced allogenic transfusion requirements. The effectiveness of rHuEPO as the only preoperative blood conservation technique was evaluated in ten patients with a predicted blood loss of less than 30% of their total volume, scheduled for lumbar surgery. Data from these patients were matched with those from a similar group of patients who had undergone ABD. Patients receiving rHuEPO alone had higher haemoglobin levels the day of surgery than did patients in the ABD program. Neither group required allogenic transfusions. Conclusions: preoperative rHuEPO is useful for reducing allogenic blood requirements in elective spine surgery. In patients with an expected blood loss of around 50% of blood volume, rHuEPO improves ABD, minimising preoperative anaemia and increasing the number of ABD units collected. In patients with expected blood loss below 30% of total volume, rHuEPO administration may replace ABD.

Reliability of retrospective clinical data to evaluate the effectiveness of lumbar fusion in chronic low back pain.

Study Design. Patients in whom a posterior spinal fusion instrumentation had been performed to treat low back pain were asked to recall their preoperative clinical status by retrospectively filling out the same 3 self-evaluation scales they had completed before surgery in a prospective fashion. Objectives. To evaluate the impact of recollection error and compare outcomes using retrospective versus prospective methodologies among a cohort of patients treated with posterior spinal fusion instrumentation. Summary of Background Data. Literature on spine surgery from 1990 to 2000 shows a greater increase in retrospective studies as compared to randomized controlled trials and other prospective studies. Cross-sectional studies evaluate therapeutic effectiveness by comparing the current condition with the recalled (retrospectively recorded) pretreatment condition. There are no studies analyzing the characteristics of recalled data in a cohort of patients with chronic low back pain treated with posterior spinal fusion instrumentation. Methods. The preoperative clinical status of 58 patients, 33 women and 25 men, with a mean age of 48.3 years (22–84 years) was assessed prospectively with 3 self evaluation questionnaires and retrospectively at a mean of 37.5 months (2–58 months) after surgery using the same questionnaires. The Wilcoxon test was used to compare prospective and retrospective preoperative data and to compare prospective outcomes with outcomes determined from cross-sectional data. Agreement between prospective and retrospective measures was estimated with intraclass correlation coefficients for absolute agreement and consistency. Results. Comparisons between prospective and recalled data showed significant differences, demonstrating a worse preoperative situation when using retrospective data. Assessment of treatment effectiveness showed that cross-sectional evaluation significantly improved the real surgical outcome. Both absolute agreement and consistency intraclass correlation coefficients showed poor agreement between prospective and cross-sectional data, revealing no systematic bias. Follow-up, age, and gender did not modify agreement and cross-sectional overestimation. Conclusions. Relying on a patient’s recall of preoperative clinical status is not an accurate method to evaluate surgical outcome after posterior spinal fusion instrumentation. Cross-sectional studies may overestimate the effectiveness of surgery.