Pre-operative bone quality deficits and risk of complications following spine fusion surgery among postmenopausal women

Poor bone quality is a risk factor for complications after spinal fusion surgery. This study investigated pre-operative bone quality in postmenopausal women undergoing spine fusion and found that those with small bones, thinner cortices and surgeries involving more vertebral levels were at highest risk for complications.

PURPOSE

Spinal fusion is one of the most common surgeries performed worldwide. While skeletal complications are common, underlying skeletal deficits are often missed by pre-operative DXA due to artifact from spinal pathology. This prospective cohort study investigated pre-operative bone quality using high resolution peripheral CT (HRpQCT) and its relation to post-operative outcomes in postmenopausal women, a population that may be at particular risk for skeletal complications. We hypothesized that women with low volumetric BMD (vBMD) and abnormal microarchitecture would have higher rates of post-operative complications.

METHODS

Pre-operative imaging included areal BMD (aBMD) by DXA, cortical and trabecular vBMD and microarchitecture of the radius and tibia by high resolution peripheral CT. Intra-operative bone quality was subjectively graded based on resistance to pedicle screw insertion. Post-operative complications were assessed by radiographs and CTs.

RESULTS

Among 50 women enrolled (age 65 years), mean spine aBMD was normal and 35% had osteoporosis by DXA at any site. Low aBMD and vBMD were associated with "poor" subjective intra-operative quality. Skeletal complications occurred in 46% over a median follow-up of 15 months. In Cox proportional models, complications were associated with greater number of surgical levels (HR 1.19 95% CI 1.06-1.34), smaller tibia total area (HR 1.67 95% CI1.16-2.44) and lower tibial cortical thickness (HR 1.35 95% CI 1.05-1.75; model p < 0.01).

CONCLUSION

Women with smaller bones, thinner cortices and procedures involving a greater number of vertebrae were at highest risk for post-operative complications, providing insights into surgical and skeletal risk factors for complications in this population.

Bone Density Distribution in the Cervical Spine

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Given changes in bone density induced by degenerative disease, general measures of bone health (ie DEXA) are inadequate to evaluate bone density in surgical areas of interest. Regional differences in HU in the cervical spine may influence surgical strategies. The purposes of our study were to determine whether cervical Hounsfield units (HU) vary by level, examine their relationship with age, comorbidities, and alignment, and propose a technique to measure HU in the lateral masses.

METHODS

Two hundred twenty-four patients with degenerative spine pathology with a cervical computed tomography were included (2015-2019). Measurements were performed in each vertebral body (C2-T1; mid-axial, anterior-axial, posterior-axial, mid-coronal, and mid-sagittal) and 2 regions of the lateral masses (C3-C6; mid-cor, mid-sag). To evaluate reliability, 6 observers each measured 355 HU values, inter-relater reliability assessed with intraclass correlation coefficients Correlations of HU with age, BMI, comorbidities, and cervical alignment were evaluated.

RESULTS

Bone density differed by level, with the lowest HU scores in the lower cervical spine (C6-T1) (P < .001). No correlations were found between LM HU and age, BMI, CCI, or alignment (P > .05). Increased kyphosis was weakly correlated with VB HU, while age and CCI showed moderate correlations with VB HU at all levels (P<.001). ICC for HU measurements were good to excellent for the VBs, but poor to moderate for the LMs.

CONCLUSION

Bone is least dense in the lower cervical spine. HU scoring is not reliable in the lateral masses. We recommend that a level-specific approach to bone density is considered in surgical planning.

Complications and Revisions After Spine Surgery in Patients With Skeletal Dysplasia: Have We Improved?

STUDY DESIGN

Retrospective case series.

OBJECTIVE

To report contemporary rates of complications and subsequent surgery after spinal surgery in patients with skeletal dysplasia.

METHODS

A case series of 25 consecutive patients who underwent spinal surgery between 2007 and 2017 were identified from a single institution's skeletal dysplasia registry. Patient demographics, medical history, surgical indication, complications, and subsequent surgeries (revisions, extension to adjacent levels, or for pathology at a non-contiguous level) were collected. Charlson comorbidity indices were calculated as a composite measure of overall health.

RESULTS

Achondroplasia was the most common skeletal dysplasia (76%) followed by spondyloepiphyseal dysplasia (20%); 1 patient had diastrophic dysplasia (4%). Average patient age was 53.2 ± 14.7 years and most patients were in excellent cardiovascular health (88% Charlson Comorbidity Index 0-4). Mean follow up after the index procedure was 57.4 ± 39.2 months (range). Indications for surgery were mostly for neurologic symptoms. The most commonly performed surgery was a multilevel thoracolumbar decompression without fusion (57%). Complications included durotomy (36%), neurologic complication (12%), and infection requiring irrigation and debridement (8%). Nine patients (36%) underwent a subsequent surgery. Three patients (12%) underwent a procedure at a non-contiguous anatomic zone, 3 (12%) underwent a revision of the previous surgery, and another 3 (12%) required extension of their previous decompression or fusion.

CONCLUSIONS

Surgical complication rates remain high after spine surgery in patients with skeletal dysplasia, likely attributable to inherent characteristics of the disease. Patients should be counseled on their risk for complication and subsequent surgery.

Early Opioid Consumption Patterns After Anterior Cervical Spine Surgery

STUDY DESIGN

This is a prospective observational study.

OBJECTIVE

The aim was to record daily opioid use and pain levels after 1-level or 2-level anterior cervical discectomy and fusion (ACDF) or cervical disc arthroplasty (CDA).

SUMMARY OF BACKGROUND DATA

Data to inform opioid prescription guidelines following ACDF or CDA is lacking. Understanding postoperative opioid consumption behaviors is critical to provide appropriate postdischarge prescriptions.

METHODS

Patients undergoing 1-level or 2-level primary ACDF or CDA were consecutively enrolled at 2 participating institutions between March 2018 and March 2019. Patients with opioid dependence (defined as daily use ≥6 mo before surgery) were excluded. Starting postoperative day 1, daily opioid use and numeric pain rating scale pain levels were collected through a Health Insurance Portability and Accountability Act-compliant, automated text-messaging system. To facilitate clinical applications, opioid use was converted from oral morphine equivalents into "pills" (oxycodone 5 mg equivalents). After 6 weeks or upon patient-reported cessation of opioid use, final survey questions were asked. Refill data were verified from the state prescription registry. Risk factors for patients in top quartile of consumption were analyzed.

RESULTS

Of 57 patients, 48 completed the daily queries (84.2%). Mean age of the patient sample was 50.2±10.9 years. Thirty-two patients (66.7%) underwent ACDF and 16 CDA (33.3%); 64.6% one level; 35.4% two levels. Median postdischarge use was 6.7 pills (range: 0-160). Cumulative opioid use did not vary between the 1-level and 2-level groups (median pill consumption, 10 interquartile range: 1.3-31.3 vs. 4 interquartile range: 0-18, respectively, P=0.085). Thirteen patients (27.1%) did not use any opioids after discharge. Of those patients that took opioids after discharge, half ceased opioids by postoperative day 8. Preoperative intermittent opioid use was associated with the top quartile of opioid consumption (9.1% vs. 50%, P=0.006).

CONCLUSION

Given that most patients use few opioids, patients could be offered the option of a 12 oxycodone 5 mg (90 oral morphine equivalents) discharge prescription, accompanied by education on appropriate opioid use and disposal.

Posterior reversible encephalopathy syndrome: temporary visual loss after spinal deformity surgery

Posterior reversible encephalopathy syndrome (PRES) is a rare cause of temporary postoperative visual loss (POVL) after spinal deformity surgery. We report on 2 patients diagnosed with PRES after spinal deformity surgery, who were closely examined postoperatively. A 78-year-old woman with severe disability due to degenerative lumbar spondylosis after laminectomy was treated with transpsoas lumbar interbody fusion from L1 to L4 and posterior spinal fusion from T10 to pelvis. She developed confusion and bilateral visual loss on postoperative day 7. A second patient, a 51-year-old woman with progressive pain and decompensation caused by adult scoliosis, was treated with posterior spinal fusion from T3 to pelvis and interbody fusion from L4 to S1 via a presacral interbody fusion approach. She developed bilateral visual loss on postoperative day 15. Both patients achieved a complete recovery of their vision after medical management of PRES. Timely diagnosis of PRES and prompt intervention allow for a good patient prognosis and complete recovery of eyesight.

Considerations for prophylactic surgery in asymptomatic severe cervical stenosis: review article

BACKGROUND

Cervical spondylotic myelopathy (CSM) is a devastating pathology that can severely impair quality of life. The symptoms in CSM progress slowly and often do not manifest until they become severe and potentially irreversible. There is a consensus that surgical intervention is warranted in symptomatic patients. The recovery of the neurologic deficit after surgical decompression of the spinal cord varies, and halting the progression of the disease remains the principle aim of surgery.

QUESTIONS/PURPOSES

The aim of this review is to address the key question of whether or not to intervene in cases that have radiographic evidence of significant cervical stenosis yet are asymptomatic or exhibit minimal symptoms?

METHODS

The PubMed databases for publications that addressed asymptomatic cervical spondylotic myelopathy were reviewed. The relevant articles were selected after screening all the resulting abstracts. The references of the relevant articles were then reviewed, and cross references with titles discussing CSM were picked up for review.

RESULTS

The search identified 14 papers which were reviewed. Seven articles were found to be relevant to the subject in question. Going through the references of the relevant articles, three articles were found to be directly related to the topic in study.

CONCLUSION

There is paucity of evidence to support for or against surgery in the setting of asymptomatic cervical spondylotic myelopathy despite radiographic evidence of severe stenosis. Patient factors such as age, level of activity, and risk of injury should be considered in formulating a management plan. Moreover, the patient should play an integral role in the process of decision making.

Long-term Results of 100 Consecutive Comprehensive Neck Dissections

OBJECTIVE

The optimal surgical procedure for the neck in patients with squamous head and neck cancers is controversial. Selective neck dissections have replaced modified radical neck dissections as the procedure of choice for the clinically negative (N0) neck and are now being considered for patients with early-stage neck disease. We report the long-term local recurrence rates in 100 consecutive patients undergoing a radical or modified radical neck dissection for clinically positive (N+) and N0 neck disease and review comprehensively the literature reporting and comparing regional control rates for both neck dissection types.

PATIENTS

The clinical records of 100 consecutive patients who underwent a comprehensive neck dissection (levels I-V) for squamous head and neck cancers with a minimum of a 2-year follow-up were retrospectively reviewed for primary site of disease, clinical and pathologic neck status, histopathologic grade, neck dissection type, and the site and time of recurrence.

RESULTS

Complete data were available for 97 patients on whom 99 neck dissections were performed. Three patients died from unknown causes. Seventy-six patients with N+ disease underwent a therapeutic neck dissection, while 24 patients with clinically N0 disease underwent an elective dissection. The overall neck recurrence rate in patients with controlled primary disease was 7%. The neck or regional failure rate for patients completing the recommended adjuvant radiotherapy was 4%. Six (25%) of 24 patients with clinically N0 disease had occult metastases. The recurrence rate for this group was 4%.

CONCLUSION

Further study is needed to determine the optimal surgical management of the N0 and limited N+ neck.