Low-Back Outcome Scale and the Oswestry Disability Index they Reflective of Patient Satisfaction

Introduction

Low back pain is the most common type of pain. The causes of many painful conditions of the low back remain obscure. Low back pain bothers not only patients but also the experts about its multidisciplinary approaches. The typical background of a low back incidence is a faulty postural pattern. A mechanical or functional strain causing muscular misbalance in one part of the body may soon result in compensatory changes in other parts. Conversely, the symptoms appearing in the low back region may be caused by faulty mechanics of the feet, legs or hip [1]. At the junction of L5/S1 apophyseal joint: the long mass of five fused vertebrae forming the sacrum articulate with the fifth lumbar vertebra and bear most of the weight and shearing forces and stress. In the standing position the lordotic curve of the lumbar spine places particular stress on the L5/S1 junction. With the wedge-shaped disc and body of L5, the tendency would be for L5 to slide forward on the sacrum [2]. There are several tools such as the Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ) [3], the Oswestry disability index (ODI) [4], the Japanese Orthopaedic Association (JOA) [5], and the Core Outcome Measures Index (COMI) [6], for measuring performance status or functionality in these patients. Diagnosis of the cause of recurrent back pain is still difficult. Many causes of recurrence of back pain after surgery have been recorded; recurrent disc herniation and postoperative fibrosis are the two major ones. It is important to distinguish these two entities as disc herniation may require re-operation, whereas postoperative fibrosis does not. MRI imaging appeared to be the examination of choice in the investigations of spine and disc diseases especially in recurrent disc prolapse. MRI with contrast (Gadolinium enhanced MRI) may differentiate post-operative fibrosis from recurrent herniation [7]. On the other hand, patient satisfaction is believed to be an attitudinal response to value judgments that patients make about their clinical experience and is associated with many variables, such as patient demographics, symptom-related expectations, functional status, mental disorders, unmet expectations, doctor–patient communication, and to a large extent, patient expectations [8]. Prior studies have shown that discectomy is a safe and effective surgical technique for the treatment of LDH based on various measures [9].

However, little is known about the correlation of patient satisfaction to functioning status after surgical treatment for LDH [10]. In addition, in some cases, spine surgeons and patients occasionally do not agree on the success of the treatment. In the case of the most minor restrictions, we know from our own experience how these can happen: sitting or working for a long time in an unfavorable position, we sense a need to stretch and move, which is to ease such minor inhibitions of movement. Minor restrictions can be present even in physiological situations and in healthy individuals and these resolve spontaneously. There is a fluid transition between such minor restrictions following physiological stress, and persistent restrictions following physiological stress and persistent restrictions following pathogenic, harmful stress [11]. Moreover, in the literature, there has been a trend toward the assessment of patient satisfaction as an outcome measure [12, 13, 14, 15, 16, 17]. Recent efforts in orthopedic research have generated insights into the efficacy, safety, and preferred methodology in dealing with recurrent post-discectomy lumbar disc herniation (LDH). Recurrent herniation of the nucleus pulposus (HNP) and subsequent disc degeneration after a discectomy is a common problem, with reported rates ranging from 2% to 25%. When it occurs, recurrent herniation is a major contributor to debilitating pain, disability, and reoperation following primary surgery, and it is therefore an important factor in determining postoperative success [18].

Materials and Methods

This prospective interventional study was conducted in department of Orthopaedic Surgery, BSMMU, Dhaka from October 2017 to September 2019. A total of 22 cases of RLDH having the inclusion criteria were taken as sample after diagnosing clinically, radiologically and with MRI. Outcome of low back pain (LBP) and radicular pain was measured by visual analogue score (VAS) and overall clinical outcome by Japanese Orthopaedic Association (JOA) score. All patients who underwent discectomy with a single-level disc herniation were eligible to be included in the study. The diagnosis of LDH was made on the basis of clinical and radiographic evidence. All participants underwent a complete clinical examination for LDH including an assessment of clinical symptoms and clinical examination, and imaging studies including plain radiography, computed tomography (CT) and magnetic resonance imaging (MRI) of the lumbar spine. In all cases more than one spine surgeon confirmed the diagnosis and experienced surgeons performed surgery. There were no restrictions on patient selection with regard to level(s) of LDH, age or other characteristics. We excluded all patients with previous back surgeries, malignancy, fracture, spinal cord compression, and spinal anomalies from the study.

Results

In this study, out of 22 patients 8 (36.4%) were 35-45 years of age, 8 (36.4%) were 46- 55years, 4 (18.2%) were 56- 65 years and 2 (9.1%) were 66-70 years old. The mean (± SD) age of the patients was 51.1±9.7 years and the youngest and the oldest patients were 35 and 70 years respectively. Among 22 subjects, majority of the study subjects 15 (68.2%) were male and only 7 (31.8%) were female. In this study, Tobacco, diabetes and hypertension were found highly associated with recurrent disc herniation. 14 (63.6%), 11 (50%) and 13 (59.1%) patients were found as tobacco users, diabetic and hypertensive. In all 13 patients underwent discectomy via laminotomy and the remaining 12 patients received fenestration, no case was observed with missed level surgery. Cauda-equina syndrome occurred in one case (4.5%). In one case (4.5%) dural laceration occurred during surgery which were repaired and no one showed CSF leakage or meningitis. No mortality rate was observed due to surgery. Patient’s scores on the PSI, the Finneson-Cooper score, the ODI and the LBOS are shown in Table 1. Based on the PSI, the ODI and the LBOS, post-surgical satisfactions were 16 (72.7), 15 (68.1) and 18 (81.8%), respectively. Mean improvement in the ODI was 21.5±12.1 and statistically was significant (P<0.001) at 2-year followup. No significant differences were observed for postsurgical satisfaction between levels of LDH (Tables 2 & 3). To determine patients’ satisfaction correlation analysis was carried out. There were weak associations between PSI and LBOS (Φ=−0.054, P=0.533; χ2 =0.388, P=0.533); PSI and ODI (Φ=−0.129, P=0.136; χ2 =2.22, P=0.136).

Values are mean (SD), number or percentage. BMI, body mass index. Table 1: Demographic data and preoperative status of patients with lumbar disc herniation (n=22).

LBOS, Low-Back Outcome Scale of Greenough and Fraser; PSI, patient satisfaction index. Table-2: Two-by-two matrices of the relationship between the LBOS and the PSI for patients’ satisfaction after surgery.

*Considering the ODI, clinically satisfied was defined as a 13-point improvement from the baseline ODI scores. ODI, Oswestry disability index; PSI, patient satisfaction index. Table 3: Two-by-two matrices of the relationship between the ODI and the PSI for patients’ satisfaction after surgery.

Discussion

One pathogenic factor is overload and another one, more frequent is disturbed movement pattern (motor stereotype) on the part of the patient, consisting of an imbalance of muscle function, which impairs the joint. Modern civilization brings with it very one-sided posture and movement causing muscular imbalance. Lack of movement together with static or postural overload are a characteristic feature of modern life. Disturbed movement patterns and static overload are probably the most frequent causes of reversible restrictions and of their occurrence and recurrence [11]. The results of current study demonstrate that mean (±SD) age of the patients was 51.1 (9.7) years with the youngest and the oldest patients were 35 and 70 years of age respectively. The recurrent lumbar disc herniation occurs in adult aged population. Almost similar to the findings observed by the various investigators from different countries [23, 24]. Majority of the study subjects 15 (68.2%) were male and only 7(31.8%) were female which was similar to the findings of Khayat, et al. [24]; Mashhadinezhad, et al. [25]. To the best of our knowledge, no published study has investigated whether the ODI and the LBOS reflects true patient satisfaction after discectomy. We demonstrated a limitation for the ODI and the LBOS as an outcome measure in reflecting patient satisfaction. In general, such measures have their own limitations and depending on their development history might give different profile from one to another scale for one identical patient. These measures usually are developed based on a classical test theory (CTT) where psychometric properties for an instrument does not include difficulties that one might experience in responding to each question. However, more recent patient-reported outcomes are those that do not assume that each item is equally difficult [item response theory (IRT)]. The IRT treats the difficulty of each item as information to be incorporated in scaling items [26]. The LDH surgery is a successful operation in majority of patients. In most patients the pain in the affected leg disappears almost immediately. However, in 10–40% of patients the symptoms either do not disappear or recur. In spite of this high symptom recurrence rate, it is reported that almost 90% of patients are satisfied with the operation according to the variety measures and the various followup assessments [18]. In this study, based on the PSI, the ODI and the LBOS, post-surgical satisfactions were 16 (72.7), 15 (68.1) and 18 (81.8%), respectively. Mean improvement in the ODI was 21.5±12.1 and statistically was significant (P<0.001) at 2-year followup. No significant differences were observed for postsurgical satisfaction between levels of LDH. To determine patients’ satisfaction correlation analysis was carried out. There were weak associations between PSI and LBOS (Φ=−0.054, P=0.533; χ2 =0.388, P=0.533); PSI and ODI (Φ=−0.129, P=0.136; χ2 =2.22, P=0.136). These observations indicate that we must seek means to improve prognostication prior to member spine surgery; i.e., we need to develop a better decisions-making and strategic planning process [18, 27]. We found that the ODI and the LBOS lacked significant association with the PSI to determine patient’s satisfaction. Hence, these measures are not reflective of true patient satisfaction after discectomy. There is a risk of underestimating patient satisfaction after discectomy based on lower levels of scores on the LBOS and the ODI measures, and there also is a risk of overestimating patient satisfaction based on higher levels of scores on the LBOS and the ODI measures. This finding could be attributed to the influence of patients’ expectations, other factors that improve satisfaction without improving outcome measures as home support visitors, functionality status, level of herniation, surgical procedure type, and preoperative counseling, in patients with LDH [28]. The literature has shown that, among other factors, patient expectations regarding surgery influence satisfaction with treatment. It has also been shown that such expectations can be altered by the information that is transmitted by the surgeon [29]. Gepstein, et al. [30] reported that preoperative expectations correlated with postoperative satisfaction rate in patients with lumbar spinal stenosis [31].

To determine patient expectations in lumbar spine surgery, Toyone et al. reported that, even if the clinical expectations were met, some patients remained dissatisfied [29]. Godil, et al. [17] showed that patient satisfaction is not a valid measure of overall quality or effectiveness of surgical spine care [31]. In addition, patient satisfaction was evaluated with a dichotomous yes/no question and may not fully represent this aspect of outcome in patients with LDH. Based on the aforementioned, it is clear that a standardized metric or objective assessment tool for comparing techniques or treatments is needed. One might inquire about the need to investigate relationships between satisfaction and quality of care.

Certainly, satisfaction and quality of care are very different terms, with very different meanings [30]. In addition, there is no doubt that the use of patient satisfaction scores represents an important target for the treatment of patients with low back pain. Moreover, patient satisfaction tools alone should not be used to represent the overall quality, safety, or effectiveness of surgical spine care [31]. However, researchers have suggested that we should examine our own patients’ satisfaction scores and seek to improve them. This may lead to an improved decision-making process for the patient [32, 33].

Conclusions

The present study suggests that the ODI and the LBOS as outcome measures do not reflect patient satisfaction after discectomy. Further work is needed in this arena to assess other factors that improve satisfaction without improving outcome measures that may influence patient satisfaction after discectomy

Limitations

Although optimal care had been tried by the researcher in every steps of the study, but there were some limitations:

• Study was conducted in a selected hospital. So, the study population might not represent the whole community.
• The sample was taken purposively. So, there may be chance of bias which can influence the results.
• The study and follow-up period was short in comparison to other studies.

Thus, further studies are needed to evaluate these parameters. Finally, due to the above-mentioned limitations, we believe the results should be interpreted with caution and one should not generalize the findings. Above all, we believe the best way to avoid these is to develop a standardized method for evaluation of patient satisfaction.