Friday, May 27, 2016
C5 palsy (C5P) is a poorly understood and relatively common complication after cervical spine surgery. It has been suggested that posterior procedures and wider laminectomy troughs are risk factors for developing C5P, though other studies have questioned those beliefs.1-4 Dr. Lee and his colleagues from Korea wanted to compare rates and outcomes of C5P following laminectomy and fusion (LF) vs. laminoplasty (LP). They retrospectively reviewed outcomes for 90 LF patients and 100 LP patients. They found a 29% rate of C5P following LF compared to 4% following LP. The severity of C5P was also more severe for the LF group, with a manual motor testing score of 2.1 for the LF C5P group and 3.5 for the LP patients with C5P. The LF group with C5P also took longer to recover (21 weeks vs. 11 weeks), and more patients in the LF group had incomplete recovery (15% vs. 0%). The authors evaluated risk factors for C5P among the LF patients and found that those who developed C5P were more likely to have myeloradicular symptoms compared to pure myelopathy (88% in the C5P group vs. 42% in the non-C5P group), more likely to have pre-operative motor weakness (65% C5P vs. 38% non-C5P), and more likely to have severe C4-C5 foraminal stenosis (77% C5P vs. 56% non-C5P). They concluded that C5P was more common after LF than LP and that the palsy was more severe after LF.
While C5P has been a recognized entity for decades, its etiology remains elusive. This study confirms the findings of previous studies that have suggested a higher rate of C5P following LF compared to LP.1,3 However, the rate of C5P in the LF cohort in this study is substantially higher than what has typically been reported in the literature. Nassr et al. reported a rate of 9.5% following LF in their large series, and Basaran et al. found a rate of 10.5% in their meta-analysis.1,3 It is unclear why the rate in this study was nearly three times higher, and it could be related to variation in underlying pathology, different surgical technique, or a more sensitive diagnostic process to identify C5P. It has been suggested that a wider laminectomy trough predisposes the patient to C5P, and the authors of the current study do not comment on the width of their decompression.4 While retrospective cohort studies have noted a higher rate of C5P in the LF population compared to the LP population, no randomized trial has been performed to evaluate this. By definition, the LF and LP populations are different and were selected to undergo different procedures. As such, it is unclear if the cause of the higher rate of C5P following LF is due to differences in the underlying pathology or is attributable to surgical technique. Until a Level 1 study is performed on this topic, we probably will not know the answer. Given that many patients for whom LF is indicated are not good candidates for LP (i.e. those with significant neck pain, neutral or slightly kyphotic posture, segmental instability, radiculopathy, etc.), the inclusion criteria for such a study would likely be so strict that the results would not generalizable to most of the myelopathy population. Given that C5P is a relatively benign complication in the long-term and that there is not clear evidence that surgical technique (i.e. LF vs. LP) contributes to its development, the rate of C5P should probably not be a main driver of surgical decision-making. The patient should undergo the procedure that the surgeon thinks will lead to the best outcome in his or her hands.
Please read Dr. Lee's article on this topic. Does this change how you view LF vs. LP? Let us know by leaving a comment on The Spine Blog.
Adam Pearson, MD, MS
Associate Web Editor
1. Basaran R, Kaner T. C5 nerve root palsy following decompression of cervical spine with anterior versus posterior types of procedures in patients with cervical myelopathy. Eur Spine J 2016.
2. Klement MR, Kleeman LT, Blizzard DJ, Gallizzi MA, Eure M, Brown CR. C5 palsy after cervical laminectomy and fusion: does width of laminectomy matter? Spine J 2016;16:462-7.
3. Nassr A, Eck JC, Ponnappan RK, Zanoun RR, Donaldson WF, 3rd, Kang JD. The incidence of C5 palsy after multilevel cervical decompression procedures: a review of 750 consecutive cases. Spine (Phila Pa 1976) 2012;37:174-8.
4. Radcliff KE, Limthongkul W, Kepler CK, et al. Cervical laminectomy width and spinal cord drift are risk factors for postoperative C5 palsy. J Spinal Disord Tech 2014;27:86-92.
Friday, May 20, 2016
Advanced age is associated with an increased comorbidity burden and higher rate of complications following surgery of any kind. As the population ages, there will be an increasing number of patients over age 80 with degenerative lumbar conditions. While many of these patients may have had lower functional expectations in the past, this age group is now expecting to remain active and has a greater enthusiasm for spinal surgery than previous generations of elderly patients. Lumbar fusion is a relatively invasive procedure with a significant rate of complications, and many surgeons are reluctant to perform fusion on elderly patients due to concerns about medical complications, wound healing problems, hardware failure, and overall worse results. In order to address this question, Dr. Marbacher and colleagues from Zurich reviewed over 700 patients over age 50 treated with one to three level lumbar fusion, with or without decompression. They identified 317 patients age 50-65 ("younger" group), 350 patients age 65-80 ("older" group), and 40 patients over 80 ("elderly" group) who met their inclusion criteria. They evaluated patient reported outcomes (i.e. Core Outcome Measures Index [COMI], global result, and patient satisfaction) out to 2 years as well as medical and surgical complications recorded during their surgical admission. The patient reported outcomes were not significantly different among the three age strata with the exception of global outcome at 3 months, which was significantly worse for the elderly group (72% "good" outcome in the elderly vs. 85% in the younger group). Medical complications were significantly higher in the elderly group (17.5% elderly vs. 7.5% younger), with cardiovascular (7.5%), cerebral (5%), and kidney/urinary (10%) complications the most common complications in the elderly cohort. Surgical complications were somewhat more common in the elderly, with dural tear being more common among the elderly (10% elderly vs. 3.5% younger). The length of stay was also somewhat longer for the elderly (11.3 days elderly vs. 10 days younger), with these lengths of stay being much longer than those observed in the United States. Based on these data, the authors concluded that elderly patients had similar patient reported outcomes but higher complication rates compared to younger patients undergoing lumbar fusion.
This paper is an important contribution to the literature as there is very little data on outcomes following lumbar fusion in octogenarians, and this population is presenting to spine surgeons in greater numbers. Spine surgeons frequently do not know how to treat these patients as they are caught in a conflict between wanting to help improve these patients' quality of life yet also wanting to avoid complications. While it comes as no surprise that elderly patients have higher rates of complications, it is reassuring that they have similar patient reported outcomes. Other studies have demonstrated that short term complications generally do not affect longer term patient reported outcomes, and this paper seems to reflect that. The worse global outcomes at three months for the elderly patients likely reflects a longer recovery time and may be capturing some of the short term morbidity associated with complications. This paper suggests that good results can be obtained with lumbar fusion in the elderly population, however, one must consider that only 40 of over 700 patients were over 80, and they likely represent a highly selected group. Despite this, they still had a significantly higher rate of complications. Additionally, the authors focused on in-hospital complications during the surgical admission, and complications occurring after discharge including wound healing problems, infection, and hardware complications may not have been captured. They reported an overall infection rate of under 1% (0% in the elderly group), which is remarkably low for lumbar fusion, suggesting that some wound complications may not have been captured. Despite the limitations inherent in this observational study design, the results indicate that age alone should not be a contra-indication to lumbar fusion. Properly selected octogenarians can do well with fusion surgery, though they need to be informed about their increased risk of complications during the informed consent process.
Please read Dr. Marbacher's paper on this topic in the May 15 issue. Does this change how you consider lumbar fusion for elderly patients? Let us know by leaving a comment on The Spine Blog.
Adam Pearson, MD, MS
Associate Web Editor
Friday, May 13, 2016
Degenerative lumbar scoliosis (DLS) is a heterogeneous condition that has been difficult to classify, study, and treat in a systematic fashion. Given the heterogeneity in symptom severity, radiographic findings, and patient characteristics, clear-cut treatment guidelines have been elusive, and there is likely marked variation in how it is treated. Depending on whom they see, the same patient could be treated with physical therapy, a small decompression surgery, or a deformity correction with osteotomies and thoracolumbopelvic fixation. In areas such as this where high quality evidence is lacking and would be difficult to produce, experts have attempted to create appropriateness criteria to guide care. The RAND/UCLA method is the most widely-accepted approach to this, and it involves a thorough literature review, creation of different clinical scenarios, and a modified Delphi process to gain consensus among a panel of experts about appropriate and inappropriate treatment for each scenario. Dr. Chen and her colleagues in the DLS Appropriateness Group went through such a process and published their results in the May 1 issue. They created 260 scenarios based on stenosis severity, curve magnitude, sagittal imbalance, curve progression, and medical comorbidities. They then assessed the appropriateness of different surgical treatment, namely combinations of decompression, fusion, and deformity correction. Not surprisingly, surgery was viewed as less appropriate for patients with mild symptoms, mild stenosis, and mild deformity and for patients with severe comorbidities. Decompression alone was considered appropriate for cases of stenosis with low magnitude curves without imbalance or progression. Fusion and deformity correction were considered appropriate for cases with greater curve magnitude, imbalance, and/or progression.
The authors should be applauded for attempting to systematize treatment of a condition that has defied classification over the years. Their findings tend to support the conventional wisdom of spine surgeons, which is not surprising since that is what they used to create the criteria. Given the lack of high quality studies on this topic—due in part to the lack of a good classification system—expert opinion is all we have to go on. In order to validate these criteria, a huge clinical study would need to be performed in order to determine if patients treated "appropriately" did better than those treated "inappropriately". While the authors have done a nice job distilling the salient factors in DLS, a greater level of detail is needed for surgeons to guide their decision-making. Where should the fusion start and end? How much sagittal imbalance is acceptable? Is an osteotomy necessary? Should the deformity be corrected or fused in situ? How should medical comorbidity affect my selection of an operation? It seems unlikely that clinical studies or practice guidelines will ever be able to reach the level of granularity needed to be clinically useful for this complex condition. Surgeons will need to continue to depend on their judgment and experience when answering these questions. When we get to the point that algorithms can determine the best surgical treatment for DLS, traditional spine surgeons can be replaced by technicians who simply carry out the surgical plan dictated by the algorithm. It seems unlikely that we'll see such progress for DLS anytime soon. Until then, guidelines like this can help organize one's thinking, but the treatment of DLS will remain more art than science.
Please read Dr. Chen's article on this topic in the May 1 issue. Does this change how you view the treatment of DLS? Let us know by leaving a comment on The Spine Blog.
Adam Pearson, MD, MS
Associate Web Editor
Saturday, May 7, 2016
Reoperation following surgical treatment of lumbar spinal stenosis (SpS) is a relatively common event. Acute surgical complications such as infection, hardware malposition, and spinal fluid leak can all necessitate reoperation in the short term. Medium and longer term problems such as progressive spondylolisthesis or recurrent stenosis at the index or adjacent levels can also lead to reoperation. Revision surgery is technically more challenging than primary surgery, leading to higher rates of complications, higher costs, and worse outcomes than primary surgery. As such, it is important to understand risk factors for reoperation so that any modifiable factors can be addressed preoperatively and so that patients can be counseled about their risk of reoperation based on their individual characteristics. In order to better understand risk factors for reoperation, Dr. Gerling and colleaugues used the Spine Patient Outcomes Research Trial (SPORT) SpS data to compare baseline characteristics between patients who underwent reoperation and those who did not. The study included over 400 patients who underwent surgical treatment for SpS, who were then followed for up to 8 years. Eighty-eight percent of patients underwent laminectomy alone, while 12% also underwent a posterolateral fusion. Over the eight years of follow-up, 18% of patients underwent reoperation, and 42% of reoperations were performed within 2 years of the index surgery. Progressive spondylolisthesis or recurrent stenosis at the index or adjacent level was the most common indication for reoperation (52% of reoperations). Acute complications (i.e. wound infection) were the next most common cause of reoperation (15% of reoperations). Despite evaluating over fifty different patient and disease characteristics, the only significant baseline difference between the reoperation and no reoperation groups was that the reoperation group had a somewhat lower rate of neurological deficit preoperatively. Given the high number of statistical comparisons and lack of any adjustment of the threshold for statistical significance (i.e. Bonferroni correction), it is expected that 1 or 2 variables would come up as "significant". As such, it is hard to know if this association is meaningful. Not suprisingly, the clinical outcomes were worse in the reoperation group. While the fusion group was quite small, there were no significant differences in clinical outcomes or reoperation rates between the fusion and no fusion groups.
This is an important paper that probably represents the largest series of prospectively followed patients undergoing reoperation following SpS surgery (77 reoperations). While the authors refer to the "overall low reoperation rate", some might find an 18% rate relatively high. This is a relatively high rate compared to other elective orthopaedic and neurosurgical procedures, though it reflects the fact that the spine is comprised of multiple levels that are subject to continued degeneration following a focal intervention. Accurate reoperation rate data are important for patients making treatment decisions. Somewhat surprisingly, there were no important patient or disease characteristics that predicted an increased risk of reoperation. While there may be some unmeasured and poorly understood factors (i.e. severity of degenerative change, intervertebral mobility, genetics, etc.) that do predict reoperation, the results suggest that most SpS patients who meet the strict indications for surgery laid out in SPORT have similar risk for reoperation. Further details about the indications for reoperation, levels involved, and the use of fusion would have been helpful as would have patient reported outcomes following the revision surgery. While future studies may provide some of these data, the current study represents a relatively large, homogenous group of SpS patients that will be difficult to recreate again.
Please read Dr. Gerling's article on this topic in the May 1 issue. Does this change how you view the risk of reoperation following surgery for SpS? Let us know by leaving a comment on The Spine Blog.
Adam Pearson, MD, MS
Associate Web Editor
Friday, April 29, 2016
The role of vertebroplasty (VP) remains poorly defined. Some physicians have suggested that it should be used more frequently for acute, painful fractures,1 while others think it should rarely if ever be used based on the results of two randomized trials that showed no benefit compared to a sham procedure2,3 Those trials have been criticized for including primarily patients who had fractures over six weeks old and some with relatively mild symptoms. Many prior studies without a sham control have shown a benefit of VP, and anecdotal evidence suggests that VP helps some patients. On the other hand, the vast majority of compression fractures will go onto heal uneventfully with minimal or no treatment over the course of 6-10 weeks. Given that most evidence on this topic has looked at outcomes for patients with subacute or chronic fractures, Dr. Yang and colleagues from Shanghai performed a non-blinded RCT comparing VP to conservative management, which included at least two weeks of bedrest followed by mobilization with bracing. All patients had acute compression fractures, with the average symptom duration prior to enrollment being 5.5 days. They randomized 135 patients, with 107 remaining compliant with their treatment assignment and completing 1 year follow-up. The VP group had better outcomes on VAS back pain, Oswestry Disability Index (ODI), and a measure specific to osteoporotic compression fractures (QUALEFFO). In the year following enrollment, 9% of VP patients and 8% of conservatively treated patients sustained at least 1 more compression fracture. The authors reported no technical complications related to VP but did note a higher rate of complications related to immobilization (i.e. pneumonia, DVT, UTI, depression, etc.) in the conservative treatment group (35% vs. 16%).
Similar to other non-blinded, randomized trials comparing VP to conservative treatment, this study showed a significant advantage for VP.1 Physicians now have to reconcile conflicting data between the non-blinded RCTs favoring VP and the blinded, sham-controlled RCTs that showed minimal or no benefit to VP. Aside from the lack of blinding, this study differed in two important ways from the sham-controlled trials. All patients in the current trial had acute fractures, with vertebroplasty being performed at an average of 3 days following diagnosis and 8 days after the onset of symptoms. Additionally, the control group in the current study was very different, with patients being prescribed a minimum of 2 weeks of bedrest, with the average patient spending 33 days at bedrest. In the United States, only a small proportion of patients require any bedrest at all, and patients are generally encouraged to mobilize as soon as possible. Two weeks of bedrest is certainly not the standard of care, and prescribing such a treatment would be considered bordering on malpractice. Given that prolonged bedrest is not a recommended treatment and is known to be associated with many complications and deconditioning, the advantages observed for VP in this trial may be due less to the benefits of VP and more related to the negative effects of prolonged bedrest. Additionally, while VP may provide faster resolution of pain than the natural history, by 6-10 weeks most fractures should be healed, and it seems unlikely that VP should result in much advantage beyond 3 months. At longer term follow-up, the advantage of VP is likely due to either the placebo effect or the negative results of prolonged bedrest. The authors seem to conclude that VP should be used more frequently for patients with acute osteoporotic compression fractures, but that conclusion is not supported by the evidence. What all of the VP studies have demonstrated is that we do not know which patients benefit most from the intervention. Patients who are bedbound by acute fractures and those who are severely limited by subacute fractures seem like two groups who are likely to benefit from VP, but these subgroups have not been well-studied. Until further studies better define the patients who stand to benefit from VP, physicians will continue to rely on intuition rather evidence while helping patients make this treatment decision.
Please read Dr. Yang's article on this topic in the April 15 issue. Does it change how you view the role of vertebroplasty? Let us know by leaving a comment on The Spine Blog.
Adam Pearson, MD, MS
Associate Web Editor
1. Farrokhi MR, Alibai E, Maghami Z. Randomized controlled trial of percutaneous vertebroplasty versus optimal medical management for the relief of pain and disability in acute osteoporotic vertebral compression fractures. J Neurosurg Spine 2011;14:561-9.
2. Buchbinder R, Osborne RH, Ebeling PR, et al. A randomized trial of vertebroplasty for painful osteoporotic vertebral fractures. N Engl J Med 2009;361:557-68.
3. Kallmes DF, Comstock BA, Heagerty PJ, et al. A randomized trial of vertebroplasty for osteoporotic spinal fractures. N Engl J Med 2009;361:569-79.