Chandra Bhatia

Significantly Improved Outcomes With a Less Invasive Posterior Lumbar Interbody Fusion Incorporating Total Facetectomy

Study Design. Original study. Objective. Prospective comparison of clinical outcomes after a standard posterior lumbar interbody fusion (ST-PLIF) and after a limited exposure PLIF incorporating total facetectomy (LI-PLIF). Summary of Background Data. Most groups have reported significantly improved clinical outcomes after ST-PLIF. To our knowledge, however, a comparison of outcomes between ST-PLIF and the LI-PLIF that we herein describe has not been reported before. Methods. Patients were included who had suffered chronic low back pain for a minimum of 2 years that was unresponsive to conservative treatment. N = 114 consecutive patients underwent ST-PLIF, whereas n = 209 underwent LI-PLIF. All patients underwent pre- and postoperative evaluations for Oswestry Disability Index (ODI), short-form 36 (SF-36), and visual analogue scores (VAS). The minimum follow-up for either group was 2 years. Results. There was a significant improvement in the ODI (22.5 ± 1.0, P < 0.001), VAS for back pain (3.8 ± 0.1, P = 0.003), VAS for leg pain (4.0 ± 0.2, P = 0.002), and SF-36 for bodily pain (14.7 ± 0.9, P = 0.012) after ST-PLIF. However, there was a significantly greater improvement in all scores after LI-PLIF: ODI (28.8 ± 1.4 vs. 22.5 ± 1.0, P < 0.001), VAS for back pain (5.4 ± 0.2 vs. 3.8 ± 0.1, P = 0.001), VAS for leg pain (5.1 ± 0.2 vs. 4.0 ± 0.2, P < 0.001), and SF-36 for bodily pain (18.5 ± 0.8 vs. 14.7 ± 0.9, P = 0.003). There was a significantly shorter duration of hospital stay after LI-PLIF (2.24 ± 0.057 days) than after ST-PLIF (4.04 ± 0.13 days) (P = 0.005). Operative complications occurred in 19.3% of ST-PLIF and in 6.7% of LI-PLIF. Conclusion. Clinical outcomes were significantly improved after both ST-PLIF and LI-PLIF. However, outcomes were significantly better after LI-PLIF than after ST-PLIF. Significantly shortened hospital stay with LI-PLIF probably reflected the “less invasive” technique per se. Significantly better clinical outcomes with fewer complications after LI-PLIF, however, potentially reflected maneuvers singular to LI-PLIF: (1) preservation of posterior elements, (2) avoidance of far lateral dissection over the transverse processes, (3) bilateral total facetectomy, (4) fewer neurologic complications, and (5) avoidance of iliac crest autograft. LI-PLIF is therefore recommended over ST-PLIF.

Cement Leakage in Percutaneous Vertebroplasty : Effect of Preinjection Gelfoam Embolization

Study Design. Prospective case series. Objectives. To determine the safety and feasibility of routine preinjection of gelfoam embolization during percutaneous vertebroplasty. Summary of Background Data. Percutaneous vertebroplasty has been used effectively in pain relief for vertebral fractures resulting from malignancy and osteoporosis. However, cement extrusion is a common problem and can lead to complications. Gelfoam embolization of venous channels before cement injection has not been widely used as a technique to prevent leakage. Methods. Thirty-one patients who met the inclusion-exclusion criteria for the study underwent percutaneous vertebroplasty. Venography was first performed to determine the flow pattern in the vertebrae and confirm needle placement. Next, routine gelfoam embolization of venous channels was performed. This was followed by low-pressure, minimal-volume cement injection. The outcome measure of cement leakage was assessed after surgery using radiographs and CT scans. Results. There were no complications. In the 31 patients, 61 levels of vertebroplasty were performed. Overall, there were 16 leaks out of 61 levels in 12 patients (26.2%). In osteoporotic fractures, there were 11 leaks in 49 levels, giving a leakage rate of 22.5%. There was only 1 epidural leak in this group (2%), and this was asymptomatic. Seven leakages were into the adjacent disc, 2 into the body, and 1 into the paravertebral tissues. In malignant fractures, there were 5 leakages out of 12 levels (41.7%). Of these, 2 were epidural leaks (16.7%), which were asymptomatic. Conclusions. Complications resulting from leakage are the most feared side effect of the procedure. This has resulted in only limited application of vertebroplasty in the United Kingdom. Routine gelfoam embolization together with careful technique has been shown to be a safe and feasible method during vertebroplasty.

Less Invasive Posterior Lumbar Interbody Fusion and Obesity: Clinical Outcomes and Return to Work

Study Design. Single-center retrospective study. Objective. The purpose of this study was to examine the relationship between obesity (body mass index [BMI] >30) and the incidence of perioperative complications, outcome of surgery, and return to work in a cohort of patients undergoing elective less invasive posterior lumbar interbody fusion (LI-PLIF) of the lumbar spine for low back pain and leg pain. Summary of Background Data. Spine surgery in the obese is challenging and an increasing problem. There are few reported studies that have assessed the incidence of perioperative complications in obese patients undergoing elective lumbar fusion procedures. To our knowledge, the effect of obesity on LI-PLIF and return to work has not been evaluated in the published data. Methods. We identified 15 patients with BMI >30 who underwent LI-PLIF by reviewing the clinical notes and the preoperative admission sheet between April 2005 and March 2007. Patients who had suffered chronic low back pain for a minimum of 2 years that had proven unresponsive to conservative treatment were included. All patients underwent pre- and postoperative evaluations for Oswestry Disability Index, short-form 36, and visual analogue scores. Minimum follow-up was for 12 months. Results. Blood loss was dependent on BMI, number of levels, and surgical time. Postoperative complication was 33.3%, which was more in the morbidly obese group than the in the obese group. Ten patients (66.6%) returned to their normal preoperative employment within 12 months of the index procedure. There was a significant improvement in the Oswestry Disability Index (14.78 ± 6.0, P = 0.03), in the visual analogue scores for back pain (3.2 ± 0.76, P = 0.001). Length of hospital stay was a mean of 3.35 days (range, 1–7). Conclusion. Surgical decision-making in the obese and morbidly obese patient is a challenge for the operating surgeon. Although surgery is technically more demanding, our experience with less invasive posterior interbody fusion has shown less incidence of postoperative complication, less intraoperative blood loss, and short in-patient hospital stay. Furthermore (66.6%) returned to their normal preoperative employment within 12 months of the index procedure. We conclude that a high BMI should not be a contraindication to surgery in patients with degenerative low back pain.

Primary erector spinae pyomyositis causing an epidural abscess: case report and literature review

BACKGROUND CONTEXT Primary pyomyositis (PM) is a rare bacterial infection of skeletal muscle usually restricted to tropical zones. Typically caused by Staphylococcus aureus, primary staphylococcal PM associated with an epidural abscess has not been reported before. PURPOSE We present the first case of staphylococcal PM associated with an epidural abscess. STUDY DESIGN Case report. PATIENT SAMPLE A 56-year-old woman. OUTCOME MEASURES Clinical follow-up at 9 months. METHODS This 56-year-old woman presented with a sudden onset of left lumbar back pain and sciatica without prior illness. She was pyrexial on admission, with elevated inflammatory markers but with no obvious systemic source of sepsis. RESULTS Spinal magnetic resonance imaging and subsequent surgery revealed an erector spinae abscess causing an epidural abscess via the left L4/5 intervertebral foramen. Both back pain and sciatica were immediately improved postoperatively. Culture revealed S aureus as the sole organism sensitive to flucloxacillin. Intravenous therapy was converted to oral after 12 days once the erythrocyte sedimentation rate had normalized and she was asymptomatic. She remains asymptomatic and without clinical signs at the 9-month follow-up. CONCLUSION Spinal infection must always be considered when back pain and sciatica are associated with clinical signs of sepsis. We present the first case of staphylococcal PM associated with an epidural abscess.

Prevalence of insomnia in patients with chronic back pain

Purpose. To estimate the prevalence of insomnia in patients with chronic back pain, and to correlate insomnia with severity of back pain and disability. Methods. 63 women and 57 men aged 24 to 83 (mean, 55) years who presented with chronic back pain for >6 months were asked to complete a self-administered questionnaire to evaluate the Insomnia Severity Index (ISI), Oswestry Disability Index (ODI), and Numerical Rating Scale (NRS) for back pain. Results. Of the 120 patients, 25 had no insomnia, 39 had sub-threshold insomnia, and 56 had clinically significant insomnia. According to the ODI, disability was minimal in 12 patients, moderate in 38, severe in 43, bed-binding in 26, and crippling in one. Of the 120 patients, 91 rated their NRS for back pain as 5 to 10 and 29 rated it as 1 to 4. Correlation was stronger between ISI and ODI than between ISI and NRS for back pain (r=0.59 vs. r=0.38). Conclusion. 47% of patients with chronic back pain had insomnia. The ODI was more reliable than the NRS for back pain to detect insomnia. Back pain should be treated early to avoid serious health problems associated with insomnia.

Effect of Psychological Status on Outcome of Posterior Lumbar Interbody Fusion Surgery

Study Design Prospective longitudinal study. Purpose To determine if preoperative psychological status affects outcome in spinal surgery. Overview of Literature Low back pain is known to have a psychosomatic component. Increased bodily awareness (somatization) and depressive symptoms are two factors that may affect outcome. It is possible to measure these components using questionnaires. Methods Patients who underwent posterior interbody fusion (PLIF) surgery were assessed preoperatively and at follow-up using a self-administered questionnaire. The visual analogue scale (VAS) for back and leg pain severity and the Oswestry Disability Index (ODI) were used as outcome measures. The psychological status of patients was classified into one of four groups using the Distress and Risk Assessment Method (DRAM); normal, at-risk, depressed somatic and distressed depressive. Results Preoperative DRAM scores showed 14 had no psychological disturbance (normal), 39 were at-risk, 11 distressed somatic, and 10 distressed depressive. There was no significant difference between the 4 groups in the mean preoperative ODI (analysis of variance, p = 0.426). There was a statistically and clinically significant improvement in the ODI after surgery for all but distressed somatic patients (9.8; range, -5.2 to 24.8; p = 0.177). VAS scores for all groups apart from the distressed somatic showed a statistically and clinically significant improvement. Our results show that preoperative psychological state affects outcome in PLIF surgery. Conclusions Patients who were classified as distressed somatic preoperatively had a less favorable outcome compared to other groups. This group of patients may benefit from formal psychological assessment before undergoing PLIF surgery.

Outcome of lumbar spinal fusion surgery in obese patients: a systematic review and meta-analysis.

The aim of this study was to determine whether obesity affects pain, surgical and functional outcomes following lumbar spinal fusion for low back pain (LBP). A systematic literature review and meta-analysis was made of those studies that compared the outcome of lumbar spinal fusion for LBP in obese and non-obese patients. A total of 17 studies were included in the meta-analysis. There was no difference in the pain and functional outcomes. Lumbar spinal fusion in the obese patient resulted in a statistically significantly greater intra-operative blood loss (weighted mean difference: 54.04 ml; 95% confidence interval (CI) 15.08 to 93.00; n = 112; p = 0.007) more complications (odds ratio: 1.91; 95% CI 1.68 to 2.18; n = 43858; p < 0.001) and longer duration of surgery (25.75 mins; 95% CI 15.61 to 35.90; n = 258; p < 0.001). Obese patients have greater intra-operative blood loss, more complications and longer duration of surgery but pain and functional outcome are similar to non-obese patients. Based on these results, obesity is not a contraindication to lumbar spinal fusion.

Efficacy of less invasive posterior lumbar interbody fusion as revision surgery for patients with recurrent symptoms after discectomy

Recurrence of back or leg pain after discectomy is a well-recognised problem with an incidence of up to 28%. Once conservative measures have failed, several surgical options are available and have been tried with varying degrees of success. In this study, 42 patients with recurrent symptoms after discectomy underwent less invasive posterior lumbar interbody fusion (LI-PLIF). Clinical outcome was measured using the Oswestry Disability Index (ODI), Short Form 36 (SF-36) questionnaires and visual analogue scales for back (VAS-BP) and leg pain (VAS-LP). There was a statistically significant improvement in all outcome measures (p < 0.001). The debate around which procedure is the most effective for these patients remains controversial. Our results show that LI-PLIF is as effective as any other surgical procedure. However, given that it is less invasive, we feel that it should be considered as the preferred option.

Does Symptom Duration Correlate Negatively With Outcome After Posterior Lumbar Interbody Fusion for Chronic Low Back Pain

Study Design. Original report. Objective. To investigate the putative negative correlation between the duration of symptoms (DOS) and outcome after surgery for chronic low back pain (CLBP). Summary of Background Data. Posterior lumbar interbody fusion (PLIF) is a well established treatment for CLBP. Anecdotally, a prolonged DOS is associated with a poor prognosis for recovery of CLBP. In one recent study, a DOS greater than 3 years predicted a poor prognosis for subsequent clinical improvement with CLBP. Methods. Patients (n = 209) underwent PLIF for CLBP who had proven unresponsive to nonoperative management for at least 6 months. A wide variety of physical and mental outcome scores were simultaneously assessed pre- and after surgery: i.e., the Oswestry Disability Index (ODI), SF-36 body score, SF-36 mental score, Visual Analogue Score (VAS) for back pain, VAS for leg pain, Hospital Anxiety Score (HAS), and Hospital Depression Score. Results. Despite a prolonged mean DOS of 84.3 ± 6.6 months, there was a significant postoperative improvement in all 7 outcome scores after PLIF. Significant improvement occurred in 181 patients (i.e., 86.6%) and was sustained at 51.6 ± 12.0 months follow-up. No significant correlation was found between DOS and any outcome score (ODI: rs = 0.013, P = 0.877; SF-36 bodily pain: rs = 0.013, P = 0.87; VAS for back pain: rs = 0.038, P = 0.656; VAS for leg pain: rs = 0.086, P = 0.310; HAS: rs = 0.511, P = 0.056; Hospital Depression Score: rs = 0.056, P = 0.509, or SF-36 mental score rs = 0.007, P = 0.935). No arbitrary DOS “cut-off” was found for which significantly different outcomes were recorded either side of the cut-off; or for which a significant correlation was revealed either side of the cut-off. Finally, no significant partial correlation was found between DOS and any outcome score after controlling for pain severity (VASback pain) before surgery. There were no significant differences in terms of age, sex, or DOS between those with improved ODI scores less than 10 compared with those with improved ODI scores greater than 10. Conclusion. The putative negative correlation between DOS and outcome was not observed under any analysis in our study. PLIF procured a rapid and sustained improvement in CLBP, even where the DOS was excessively prolonged; and even after having allowed for pain severity. Symptom chronicity, therefore, does not represent a poor prognostic indicator for CLBP outcome after PLIF: PLIF should be considered irrespective of DOS. Because DOS and pain severity are likely mediators of “central sensitization,” the hypothesis that central sensitization may be prevalent in CLBP patients selected for PLIF is therefore questioned.

Nonoperative Management of a Multi-Regional Epidural Abscess with Neurological Dysfunction

Spinal epidural abscesses are uncommon, but their incidence is increasing. They represent a collection of purulent material in the epidural space and most commonly occur in the lumbar spine, where they remain localised. Abscesses that affect all three spinal levels (holospinal or multiregional abscesses) are extremely rare, with only a few cases published in the literature. Epidural abscesses are particularly high risk infections as progressive neurological dysfunction can occur rapidly; early diagnosis and treatment is therefore essential to avoid long term neurological complications and reduce potential mortality. Given the uncommon nature of this condition, the treatment remains controversial with no definitive guidance on conservative versus surgical management. The literature mostly recommends surgical decompression along with intravenous antibiotics in patients with neurological abnormalities. We describe a case of a 77-year-old patient presenting with a delayed diagnosis of a multi-regional epidural abscess with associated upper motor neurone signs. The patient was successfully treated nonoperatively with a course of antibiotics resulting in complete radiological resolution of the abscess and full neurological recovery.