The Spine Blog

Saturday, August 12, 2017

Surgical treatment for coccydynia is controversial, with many surgeons skeptical about its effectiveness despite a lack of literature on the topic. Given spine surgeons’ general enthusiasm for surgery, the source of this skepticism is unclear. Most currently practicing spine surgeons do not have much experience with the procedure, and they may rely on anecdote passed along from previous generations of surgeons who had poor results with coccygectomy. In order to better understand the results of surgical and non-surgical treatment of coccydynia, Dr. Kleimeyer and colleagues from Stanford performed a retrospective cohort study that included 40 patients treated with complete coccygectomy and 48 patients treated non-operatively (treatments included sitting aids, physical therapy and injections). The groups were similar at baseline, with approximately 75% of patients being female, average age of 46, just under half recalling a traumatic event inciting the pain, and both groups reporting a baseline pain score of 7 on a 10 point scale. At an average follow-up of nearly 5 years, the surgery group’s pain score had improved to 2 compared to 5 for the non-surgical group. Other patient reported outcome measures such as the EQ-5D, coccydynia disability index, and PROMIS pain interference score were also significantly better in the surgical group. Seventy-nine percent of surgery patients reported an improvement in symptoms compared to 43% in the non-surgical group. There was a 28% wound healing complication rate (n=11) in the coccygectomy group, with 4 of the 11 requiring irrigation and debridement.

The authors should be congratulated for assembling a relatively large series of coccydynia patients undergoing surgical and non-surgical treatment. Much of the literature on this topic has included only surgical patients, so comparison to non-surgical care has been very limited. While this study has all of the limitations inherent to a retrospective cohort design, it suggests that surgery results in good outcomes for the majority of patients. The outcomes for the non-surgical group were mediocre, with the majority of patients reporting no improvement. Given that patients were required to have had symptoms and some form of non-operative treatment for at least 2 years in order to be included in the study, it is not surprising that continuing the same type of care that had failed for two years was not effective. Readers should keep in mind that these results probably do not generalize to the more acute coccydynia population, for whom non-surgical treatment is likely more effective than in this chronic pain population. The major limitation of observational studies is the potential for selection bias and confounding by unmeasured variables. It is likely that the surgical and non-surgical patients were different in ways not measured by this study, and the non-surgical group may have had characteristics associated with worse outcomes (i.e. medical or psychosocial comorbidities, lower educational attainment or socioeconomic status, smoking, receiving worker’s compensation, etc.) that were less common in the surgical group. Despite the limitations of this study, it seems reasonable to consider coccygectomy for patients suffering coccydynia refractory to treatment with non-operative approaches. Like any spine procedure, success is predicated on an accurate anatomic diagnosis, avoiding surgery in patients with comorbidities that preclude a successful outcome, and avoiding complications. The high rate of wound healing complications may contribute to spine surgeons’ reluctance to perform coccygectomy, though long-term outcomes did not seem to be negatively affected by the presence of a wound problem.

Please read Dr. Kleimeyer’s article on this topic in the August 15 issue. Does this article increase your enthusiasm for coccygectomy? Let us know by leaving a comment on The Spine Blog.

Adam Pearson, MD, MS

Associate Web Editor


Friday, August 4, 2017

Pseudomeningoceles leading to headaches, nausea, and pain are a complication that is frustrating to both patients and spine surgeons. While incidental durotomies are common, symptomatic pseudomeningoceles are fortunately rare. That has led to a relatively small literature on the topic comprised primarily of case reports. Treatment options include bedrest, abdominal binder use, lumbar drain, blood patch, and surgical repair. Epidural blood patch is standard of care for low pressure headaches following dural puncture procedures (i.e. spinal anesthesia, myelogram), and is generally regarded as having a high success rate. Its effectiveness for pseudomeningocele following lumbar decompressive surgery is unclear as no study with more than a handful of patients has been published. Some skepticism among spine surgeons exists as, unlike the situation with dural puncture procedures, the epidural space has been opened by the decompression procedure, and the blood injected during the blood patch procedure is no longer contained within the epidural space. In order to evaluate the effectiveness of the procedure, Dr. Sandwell and colleagues from the University of Rochester reviewed a consecutive series of 19 patients with post-operative pseudomeningoceles who were treated with an epidural blood patch. All patients had undergone a lumbar laminectomy with or without fusion, and 2 had undergone intradural procedures. Prior to blood patch, four had failed to improve despite surgical re-exploration and attempts at durotomy closure, and one had failed to improve despite treatment with a lumbar drain. The blood patch was performed by first aspirating the pseudomeningocele (if possible) and then injecting freshly drawn blood into the pseudomeningocele cavity as well as into the epidural space. Patients then laid flat for at least one hour prior to mobilizing. The authors report that 16/19 patients had resolution of symptoms following blood patch, and 3 of those treated successfully required either 2 or 3 blood patch procedures. Three patients failed to improve following the blood patch procedure, and all of these patients had pseudomeningocele symptoms for at least 280 days prior to the blood patch. MRI was performed on 15 patients following the blood patch, and this demonstrated resolution of the pseudomeningocele in the 12 patients in whom symptoms resolved and persistence of the pseudomeningocele in the 3 who failed to improve.

 

The authors should be congratulated for assembling the largest case series ever published on this topic. The literature on treatment of relatively rare complications is generally sparse as individual institutions do not have sufficient numbers of patients with rare complications to perform meaningful analyses. This series of under 19 patients from an institution with a busy spine surgery practice spanned 7 years, demonstrating how difficult it is to assemble such a cohort. This is still a relatively small case series and does not compare blood patch to other treatment strategies, so it is inappropriate to make strong conclusions about how this should affect clinical practice. Additionally, the patients had undergone a wide variety of surgeries and had varying types of treatment aimed at the pseudomeningocele prior to the blood patch. The duration of symptoms was also highly variable, ranging from 5 to 448 days. The authors also do not discuss the characteristics of the dural defect leading to the pseudomeningocele, which can range from a pinhole sized incidental durotomy to a massive, irreparable dural tear. While this study is Level IV evidence and carries all of the limitations inherent to a case series, it does suggest that attempting a pseudomeningocele aspiration and blood patch early on in the treatment of a pseudomeningocele is reasonable and could prevent many patients from undergoing more invasive procedures such as lumbar drain placement or surgical re-exploration. Given the low number of patients with this complication and the heterogeneity of pseudomeningoceles in general, it is unlikely that we will ever have better than Level IV evidence on this topic.

Please read Dr. Sandwell’s article in the August 1 issue. Does this article change how you view the role of blood patch in the treatment of pseudomeningoceles? Let us know by leaving a comment on The Spine Blog.

Adam Pearson, MD, MS

Associate Web Editor


Friday, July 28, 2017

Debate on healthcare reform has been front and center this summer, with Congress attempting—so far unsuccessfully—to repeal, replace, or improve the Affordable Care Act (ACA). Congressional Budget Office estimates about the number of “insured” people treat all insurance as equal. As long as one has private insurance, Medicaid, or Medicare, they are considered “insured”. However, different insurance plans offer markedly different benefits, and many physicians are selective in the type of insurance they will accept, primarily due to significant differences in reimbursement across the different plans. To understand the effect of insurance type on access to surgical spine care, Mr. Anandasivam and colleagues from Yale School of Medicine designed a fascinating study. The authors randomly selected 15 neurosurgeons and 15 orthopaedic spine surgeons from 8 different states (4 that had expanded Medicaid through the ACA and 4 that had not) and contacted their offices attempting to set up an appointment for their fictitious 45 year old uncle with radiculopathy and a lumbar disc herniation. Each office was contacted twice, once with the caller reporting the uncle had BlueCross insurance and the other time indicating he had Medicaid. They found that 95% of surgeons would schedule an appointment for the BlueCross patient, while only 0.8% would schedule the Medicaid patient. Additionally, only 4% of surgeons required a referral to see the BlueCross patient, while 93% required a referral for the Medicaid patient. These numbers did not vary substantially whether the state had expanded Medicaid or not. There were no differences when the results were compared between neurosurgeons and orthopaedic spine surgeons.

The authors should be congratulated on devising a creative study design that effectively exposed the marked disparity in access to basic spine care based on insurance type. This paper highlights the fact that Medicaid patients generally do not have access to elective spine surgery, given that fewer than 1% of spine surgeons were willing to schedule an appointment when their office was called with a clinical scenario appropriate for surgical evaluation. While somewhat different results may have been achieved if more states had been included, the disparity in access between the two insurance types was so striking and so consistent across the 8 included states, it seems unlikely that the results would have changed much. Papers like this should get the attention of policymakers, as they make it clear that simply expanding Medicaid is not going to markedly improve low-income patients’ access to healthcare. It may be politically convenient to tout the millions of more patients insured under Medicaid expansion, however, these patients may not notice much of a difference if they cannot find a doctor. Some may criticize spine surgeons for refusing to take care of Medicaid patients, but most reasonable people would agree that paying a spine surgeon $543 to perform a discectomy and 90 days of aftercare (as is done by New York Medicaid) is insufficient when taking into account overhead and taxes. Articles like this one that illuminate what is actually happening on the ground level should catch the attention of policy makers and make it clear that simply expanding Medicaid may not translate to better healthcare for low income Americans. Unfortunately, it is much easier to believe that it does rather than doing the hard work in coming up with real solutions to the challenges faced by our healthcare system.

Please read Mr. Anandasivam’s article in the August 1 issue. While this article was written over a year ago, it seems quite germane to the current healthcare debate. Let us know your thoughts by leaving a comment on The Spine Blog.

Adam Pearson, MD, MS

Associate Web Editor


Friday, July 21, 2017

The high rate of mechanical failure, revision surgery, and complications following adult spinal deformity (ASD) surgery is well-documented in the spine literature. Increasing age, 3 column osteotomy (3CO), and large changes in alignment are known risk factors for mechanical failure. While most authors have advocated correcting sagittal alignment parameters to as close to “normal” as possible, there is not strong literature indicating that achieving “normal” alignment is protective against mechanical failure. To better understand risk factors for mechanical failure following ASD surgery, Dr. Hallagher and colleagues from Denmark analyzed data from 138 ASD surgery patients with a mean follow-up of 4 years to determine risk factors for mechanical failure. They defined mechanical failure as revision surgery for pseudarthrosis, hardware failure, junctional kyphosis or fracture. The average age was 61, 70% of patients were female, the average fusion length was 10 levels, 71% were fused to the sacrum or pelvis, 44% had 3CO, and no BMP was used. Overall, 47% of patients underwent revision surgery for mechanical failure, with survival analysis suggesting a 5 year mechanical failure rate of 56%. Significant risk factors for failure included 3CO (OR=1.7), lowest instrumented vertebra L5 or S1 (OR=6.6), iliac fixation (OR=2.2), SVA change > 8 cm (OR=1.9), thoracic kyphosis > 40 degrees preoperatively (OR=2.0) or 50 degrees post-operatively (OR=2.4), increase in lumbar lordosis > 30 degrees (OR=1.9), or postoperative sacral slope < 30 degrees (OR=2.3). Achieving “normal” sagittal parameters did not protect against mechanical failure, and, if anything, was associated with a trend towards greater risk of failure.

The authors should be congratulated for putting together a large series of ASD patients and presenting honest results that show a high rate of mechanical failure. This paper adds to the literature suggesting that aggressive correction of deformity in the older population—especially with the use of 3CO—is associated with a high rate of mechanical failure. In this series, achieving “normal” sagittal alignment did not prevent mechanical failure, and the literature addressing this is mixed. Like all observational studies, this series has limitations that need to be considered when interpreting the results. The patient population was very heterogeneous, including typical, older adult deformity patients with kyphoscoliosis as well as younger patients who were likely being treated for idiopathic scoliosis. The authors also did not report on the rates of different kinds of mechanical failure, with junctional kyphosis being lumped together with pseudarthrosis. Additionally, no BMP was used, and it has been shown that BMP-2 use can reduce the rate of pseudarthrosis in long thoracolumbar fusions to the pelvis. Despite these limitations, this paper—and others—strongly suggest that aggressive correction of sagittal imbalance is associated with a high rate of mechanical failure. This is not surprising, given that these deformities are longstanding and are associated with contraction of soft-tissues on the ventral aspect of the spine and weakness of the extensor musculature. While osteotomies can correct the bony malalignment, they don’t address the soft tissue issues. As a result, strong deforming forces remain that push the spine back towards its original, malaligned state. These forces can result in mechanical failure either within the fusion construct or at the proximal junctional level. Data seems to be accruing to suggest that aggressive correction of sagittal imbalance in the older patient increases the mechanical failure rate, yet undercorrection may result in worse patient reported outcomes. This leaves the deformity surgeon in the difficult position of trying to find a balance between “normal” sagittal alignment and just enough correction to improve outcomes while minimizing risk for mechanical failure.

Please read Dr. Hallagher’s article on this topic in the July 15 issue. Does this change your view of aggressive correction of sagittal imbalance in the older adult deformity patient? Let us know by leaving a comment on The Spine Blog.

Adam Pearson, MD, MS

Associate Web Editor


Saturday, July 15, 2017

Whether to perform a fusion along with a revision discectomy when treating a recurrent disk herniation remains a controversial decision in spine surgery. While authors have suggested theoretical benefits to fusion, there is scant literature supporting this practice. Most studies have suggested that most patients do fairly well with a revision discectomy without a fusion, though outcomes are probably not as quite as good as the primary surgery, and there may be a higher complication rate.1 There is no literature on this topic in the workers’ compensation (WC) population, so Dr. O’Donnell and colleagues from Cleveland analyzed the Ohio Bureau of Workers’ Compensation database to compare outcomes between recurrent disc herniation patients treated with revision discectomy (RD) and revision discectomy and fusion (RDF). Of over 10,000 WC patients diagnosed with a lumbar disc herniation between 2005 and 2012, they identified 298 who underwent single level RD (n=102) or RDF (n=196). The two groups were similar at baseline, though the RDF group had a significantly higher rate of legal representation (92% vs. 82%) and a trend towards a higher proportion with psychological comorbidities (14% vs. 7%) and preoperative opioid use (51% vs. 39%). The authors found that the RD patients returned to work (RTW) at a significantly higher rate than the RDF patients (40% vs. 27%), used opioids for a significantly shorter period of time (409 vs. 661 days), and had approximately $35,000 less in medical bills. Logistic regression analysis revealed that psychiatric comorbidities, using opioids following reoperation, and having a fusion were all independent predictors of not returning to work.

The authors have done a nice job adding a new finding to the WC literature, and the results of this study are in-line with their findings in previous studies that have demonstrated low RTW rates in WC patients undergoing fusion. The WC population has notoriously poor outcomes, and the 27% RTW rate in this young, healthy population undergoing RDF is no exception. The 40% RTW rate in the RD cohort is far from stellar, though it is significantly better than the RDF group. There are clear limitations to a retrospective cohort study based on an administrative database like this one, namely that unmeasured confounders could be contributing to some of the observed differences in RTW rate between the two groups. Another major limitation is a lack of patient reported outcome measures, so we do not know if symptom severity was different at baseline or post-operatively. Return to work typically does not correlate well with pain or function in the WC population, so RTW cannot be used as a surrogate for these other outcomes.2 The authors admit that these data do not provide strong evidence regarding the indications for a fusion accompanying revision discectomy. However, it is clear that the addition of a fusion did not improve RTW rates in the WC population, and performing a fusion may have contributed to worse RTW rates. The addition of a fusion to a revision discectomy may be appropriate for certain recurrent herniation patients, though the literature does not make it clear how to identify these patients, and the majority of recurrent disk herniation patients will likely do equally as well or better with a revision discectomy alone.


Please read Dr. O’Connell’s article on this topic in the July 15 issue. Does this change how you consider the role of fusion for recurrent disc herniation in the workers’ compensation population? Let us know by leaving a comment on The Spine Blog.

Adam Pearson, MD, MS

Associate Web Editor

REFERENCES

1.            Abdu RW, Abdu WA, Pearson AM, Zhao W, Lurie JD, Weinstein JN. Reoperation for Recurrent Intervertebral Disc Herniation in the Spine Patient Outcomes Research Trial: Analysis of Rate, Risk Factors, and Outcome. Spine (Phila Pa 1976) 2017;42:1106-14.

2.            Atlas SJ, Tosteson TD, Blood EA, Skinner JS, Pransky GS, Weinstein JN. The impact of workers' compensation on outcomes of surgical and nonoperative therapy for patients with a lumbar disc herniation: SPORT. Spine (Phila Pa 1976) 2010;35:89-97.