Impact of age within younger populations on outcomes following cervical surgery in the ambulatory setting

ObjectiveTo determine the effect of age within the younger population seen at ambulatory surgical centers on patient-reported outcome measures (PROMs) after cervical spine surgery.MethodsPatients of age <65 years undergoing single-level anterior cervical discectomy and fusion (ACDF) or cervical disc replacement (CDR) were included. Patients were divided by mean age of initial population (46 years). PROMs included Patient-reported Outcome Measurement Information System Physical Function (PROMIS-PF), 12-Item Short-Form Physical Component Survey (SF-12 PCS), Visual Analog Scale (VAS) neck, VAS arm, Neck Disability Index (NDI) collected preoperatively and at postoperative time points up to 2 years.Results138 patients were included, with 66 patients <46 years. Both cohorts demonstrated improvement from preoperative baseline with regard to all studied PROMs at multiple time points postoperatively (p ≤ 0.042, all). Between groups, the older cohort demonstrated greater mean PROMIS-PF scores preoperatively and at 6 weeks (p ≤ 0.011, both), while VAS arm scores were lower in the older group at 1 year (p = 0.002), and NDI scores were lower in the older group at 6 weeks and 1 year (p < 0.027, both). Minimal Clinically Important Difference (MCID) achievement rates were greater in the younger group in PROMIS PF at 2 years (p = 0.002), and in the older group in VAS arm score at 1 year (p = 0.007).ConclusionBoth cohorts showed significant improvement at multiple postoperative time points for all PROMs. Between groups, the older group reported more favorable physical function, VAS arm, and NDI scores at several time points. However, MCID achievement rates only significantly differed in two PROMs at singular time points. Difference in age in patients <65 years likely does not significantly affect long-term outcomes after cervical spine surgery.     

Multimodal analgesic protocol for cervical disc replacement in the ambulatory setting: Clinical case series

BackgroundEffective pain management is paramount for outpatient surgical success. This study aims to report a case series of patients undergoing cervical disc replacement (CDR) in an ambulatory surgery center (ASC) with the use of an enhanced multimodal analgesic (MMA) protocol.MethodsPrimary, single-/2-level CDR procedures at an ASC with an enhanced MMA protocol were included. ASC patients were discharged day of surgery. Patient-reported outcome measures (PROMs) were administered at preoperative/6-week/12-week/6-month/1-year/2-year timepoints and included Visual Analogue Scale (VAS) neck, VAS arm, Neck Disability Index (NDI), Patient-Reported Outcomes Measurement Information System-Physical Function (PROMIS-PF), and 12-Item Short-Form Physical and Mental Composite Score (SF-12 PCS/SF-12 MCS). A t-test assessed postoperative PROM improvement from baseline. MCID achievement was determined by comparing ΔPROM scores to previously established thresholds.Results106 patients were included, 76 single-level and 30 2-level. Most single-levels occurred at C5–C6, most 2-levels at C5–C7. One 2-level patient developed a hematoma 5 days postoperatively and underwent revision for evacuation. Five patients reported postoperative dysphagia; all were quickly resolved. One patient had an episode of seizure secondary to serotonin syndrome from concealed drug use. Patient was reintubated, transferred, and treated for serotonin syndrome. Two patients experienced postoperative nausea/vomiting. Cohort significantly improved from baseline for all PROMS at all timepoints except SF-12 MCS at 1-year/2-years and SF-12 PCS at 2 years (p < 0.047, all). Overall MCID achievement rates were: VAS arm (48.7%), VAS neck (69.1%), NDI (98.9%), SF-12 MCS (50.0%), SF-12 PCS (54.6%), and PROMIS-PF (73.4%).ConclusionOutpatient CDR, incorporating an enhanced MMA protocol, can be safely and effectively performed with proper patient selection and surgical technique. Patients saw timely discharge, well-controlled postoperative pain, and favorable long-term outcomes.     

Outcomes of cervical disc replacement in patients with neck pain greater than arm pain

BACKGROUND CONTEXTAlthough anterior cervical discectomy and fusion is believed to positively impact a patient's radicular symptoms as well as axial neck pain, the outcomes of cervical disc replacement (CDR) with regards to neck pain specifically have not been established.PURPOSEPrimary: to assess clinical improvement following CDR in patients with neck pain greater than arm pain. Secondary: to compare the clinical outcomes between patients undergoing CDR for predominant neck pain (pNP), predominant arm pain (pAP), and equal neck and arm pain (ENAP).STUDY DESIGNRetrospective review of prospectively collected data.PATIENT SAMPLEPatients who had undergone one- or two-level CDR for the treatment of degenerative cervical pathology and had a minimum of 6-month follow-up were included and stratified into three cohorts based on their predominant location of pain: pNP, pAP, and ENAP.OUTCOME MEASURESPatient-reported outcomes: Neck Disability Index (NDI), Visual Analog Scale (VAS) neck and arm, Short Form 12-Item Physical Health Score (SF12-PHS), Short Form 12-Item Mental Health Score (SF12-MHS), minimal clinically important difference (MCID).METHODSChanges in Patient-reported outcomes from preoperative values to early (<6 months) and late (≥6 months) postoperative timepoints were analyzed within each of the three groups. The percentage of patients achieving MCID was also evaluated.RESULTSOne hundred twenty-five patients (52 pNP, 30 pAP, 43 ENAP) were included. The pNP cohort demonstrated significant improvements in early and late NDI and VAS-Neck, early SF-12 MCS, and late SF-12 PCS. The pAP and ENAP cohorts demonstrated significant improvements in all PROMs, including NDI, VAS-Neck, VAS-Arm, SF-12 PCS, and SF-12 MCS, at both the early and late timepoints. No statistically significant differences were found in the MCID achievement rates for NDI, VAS-Neck, SF-12 PCS, and SF-12 MCS at the late timepoint amongst the three groups.CONCLUSIONSCDR leads to comparable improvement in neck pain and disability in patients presenting with neck pain greater than arm pain and meeting specific clinical and radiographic criteria.     

Which NDI domains best predict change in physical function in patients undergoing cervical spine surgery?

Background ContextPhysical function is a critical aspect of patient outcomes. NDI is a widely validated outcome measure in cervical spine disease, yet to what extent its individual domains predict changes in physical function remains unknown.PurposeTo examine the impact of individual NDI domains on changes in physical function in patients undergoing cervical spine surgery.Study Design/SettingProspective Cohort Study.Patient SampleAdult patients undergoing cervical spine surgery, excluding those undergoing surgery for instability due to trauma.Outcome MeasuresAbsolute change in outcome measures (Patient Reported Outcomes Measurement Information System [PROMIS] Physical Function [PF], Short Form 36 [SF-36] Physical Component Score [PCS], and Neck Disability Index [NDI]) from pre- to postoperatively, correlation of NDI individual domains with PROMIS PF and SF-36 PCS (preoperatively, postoperatively, and change from pre- to postoperatively).MethodsPatients undergoing cervical spine surgery between 2016 and 2018 were prospectively enrolled. Patients completed questionnaires (NDI, SF-36 PCS, and PROMIS PF) preoperatively and at 6 months postoperatively. Patient demographics, including age, body mass index, Charlson Comorbidity Index, and underlying diagnoses were collected. Comparisons between NDI scores preoperatively versus postoperatively were conducted using Wilcoxon signed rank sum test. Correlations of NDI individual items and PROMIS/SF-36 were assessed using Pearson correlation. A stepwise linear regression analysis was performed to identify NDI items that are independently predictive of PROMIS PF and SF-36 PCS.ResultsA total of 137 patients were included in the study, with mean age 56.9 years (range 24.4–84.9). Each of the NDI domains as well as PROMIS PF and SF-36 PCS demonstrated significant improvement following cervical spine surgery (p<.001). Changes in all NDI domains demonstrated significant negative correlation with changes in PROMIS PF, with recreation (R=−0.537, p<.001), work (R=−0.514, p<.001), and pain intensity (R=−0.488, p<.001) having the greatest negative correlation. Changes in all NDI domains demonstrated significant negative correlation with changes in SF-36 PCS, with recreation (R=−0.451, p<.001), work (R=−0.443, p<.001), lifting (R=−0.373, p<.001), and driving (R=−0.373, p<.001) having the greatest negative correlation. For PROMIS PF, the NDI domains that were independently associated with changes in PF were work (R=−0.092, p=.001), pain intensity (R=−0.089, p=.003), and recreation (R=−0.067, p=.004). For SF-36 PCS, the NDI items that were independently associated with changes in PCS were work (R=−0.269, p=.003) and recreation (R=−0.215, p=.002).ConclusionsAll NDI domains improve significantly after cervical spine surgery and demonstrate significant correlation with changes in PROMIS PF and SF-36 PCS. The work, recreation, and pain intensity domains were the only independent predictors of physical function changes postoperatively. Considering physical function, our findings highlight the importance of presenting changes in individual NDI domains in addition to the total score.     

Association between muscle health and patient-reported outcomes after lumbar microdiscectomy: early results

BACKGROUND CONTEXTPoor muscle health has been implicated as a source of back pain among patients with lumbar spine pathology. Recently, a novel magnetic resonance imaging (MRI)-based lumbar muscle health grade was shown to correlate with health-related quality of life scores. However, the impact of muscle health on postoperative functional outcomes following spine surgery remains to be investigated.PURPOSETo determine whether muscle health grade measured by preoperative psoas and paralumbar muscle cross-sectional areas impact the achievement of minimal clinically important difference (MCID) following lumbar microdiscectomy.STUDY DESIGN/SETTINGRetrospective cohort study.PATIENT SAMPLEConsecutive patients who underwent 1-level lumbar microdiscectomy in a single institution between 2017 and 2021.OUTCOME MEASURESRate of MCID achievement, time to MCID achievement, PROMs including Oswestry Disability Index (ODI), visual analog scale for back pain (VAS back), VAS leg, Short Form 12 Physical Component Summary (SF-12 PCS), SF-12 Mental Component Summary (SF-12 MCS), and Patient Reported Outcomes Measurement Information System Physical Function (PROMIS PF).METHODSTwo previously validated methods for muscle health grading were applied. Axial T2 MRI were analyzed for muscle measurements. The psoas-based method utilized the normalized total psoas area (NTPA), which is the psoas cross-sectional area divided by the square of patient height (mm²/m²). Patients were divided into low and high NTPA groups based on sex-specific lowest quartile NTPA thresholds. The paralumbar-based method incorporated the paralumbar cross-sectional area normalized by body mass index (PL-CSA/BMI) and Goutallier classification. Score of 1 was added for either PL-CSA/BMI >130 or Goutallier class of ≤2. “Good” muscle health was defined as score of 2, and “poor” muscle health was defined as score of 0 to 1. Prospectively collected PROMs were analyzed at 2-week, 6-week, 3-month, 6-month, 1-year, and 2-year postoperative timepoints. The rate of and time to MCID achievement were compared among the cohorts. Bivariate analyses were performed to assess for correlations between psoas/paralumbar cross-sectional areas and change in PROM scores from baseline.RESULTSThe total cohort included 163 patients with minimum follow-up of 6 months and mean follow-up of 16.5 months. 40 patients (24.5%) were categorized into the low NTPA group, and 55 patients (33.7%) were categorized into the poor paralumbar muscle group. Low NTPA was associated with older age, lower BMI, and greater frequencies of Charlson Comorbidity Index (CCI) ≥1. Poor paralumbar muscle health was associated with older age, female sex, higher BMI, and CCI ≥1. There were no differences in rates of MCID achievement for any PROMs between low versus high NTPA groups or between poor versus good paralumbar groups. Low NTPA was associated with longer time to MCID achievement for ODI, VAS back, VAS leg, and SF-12 MCS. Poor paralumbar muscle health was associated with longer time to MCID achievement for VAS back, VAS leg, and SF-12 PCS. NTPA negatively correlated with change in VAS back (6-week, 12-week) and VAS leg (6-month). PL-CSA/BMI positively correlated with change in PROMIS-PF at 3 months follow-up.CONCLUSIONSAmong patients undergoing lumbar microdiscectomy, patients with worse muscle health grades achieved MCID at similar rates but required longer time to achieve MCID. Lower NTPA was weakly correlated with larger improvements in pain scores. PL-CSA/BMI positively correlated with change in PROMIS-PF. Our findings suggest that with regards to functional outcomes, patients with worse muscle health may take longer to recuperate postoperatively compared to those with better muscle health.     

Patients with radiculopathy have worse baseline disability and greater improvements following anterior cervical discectomy and fusion compared to patients with myelopathy

BACKGROUND CONTEXTAnterior cervical discectomy and fusion (ACDF) is commonly performed in patients with radiculopathy and myelopathy. Although the goal of surgery in patients with radiculopathy is to improve function and reduce pain, patients with myelopathy undergo surgery to halt disease progression. Although the expectations between these preoperative diagnoses are generally understood to be disparate by spine surgeons, there is limited literature demonstrating their discordant outcomes.PURPOSETo compare improvements in patient reported outcome measures (PROMs) for patients undergoing ACDF for myelopathy or radiculopathy. Secondarily, we analyzed the proportion of patients who attain the minimum clinically important difference (MCID) postoperatively using thresholds derived from radiculopathy, myelopathy, and mixed cohort studies.STUDY DESIGN/SETTINGSingle institution retrospective cohort studyPATIENT SAMPLEPatients undergoing primary, elective ACDF with a preoperative diagnosis of radiculopathy or myelopathy and a complete set of preoperative and one-year postoperative PROMs.OUTCOME MEASURESOutcome measures included the following PROMs: Short-Form 12 Physical Component (PCS-12) and Mental Component (MCS-12) scores, the Visual Analog Scale (VAS) Arm score, and the Neck Disability Index (NDI). Hospital readmissions and revision surgery were also collected and evaluated.METHODSPatients undergoing an ACDF from 2014 to 2020 were identified and grouped based on preoperative diagnosis (radiculopathy or myelopathy). We utilized “general MCID” thresholds from a cohort of patients with degenerative spine conditions, and “specific MCID” thresholds generated from cohorts of patients with myelopathy or radiculopathy, respectively. Multivariate linear regressions were performed for delta (?) PROMs and multivariate logistic regressions were performed for both general and specific MCID improvements.RESULTSA total of 798 patients met inclusion criteria. Patients with myelopathy had better baseline function and arm pain (MCS-12: 49.6 vs 47.6, p=.018; VAS Arm: 3.94 vs 6.02, p<.001; and NDI: 34.1 vs 41.9, p<.001), were older (p<.001), had more comorbidities (p=.014), more levels fused (p<.001), and had decreased improvement in PROMs following surgery compared to patients with radiculopathy (?PCS-12: 4.76 vs 7.21, p=.006; ?VAS Arm: -1.69 vs -3.70, p<.001; and ?NDI: -11.94 vs -18.61, p<.001). On multivariate analysis, radiculopathy was an independent predictor of increased improvement in PCS-12 (β=2.10, p=.019), ?NDI (β=-5.36, p<.001), and ?VAS Arm (β=-1.93, p<.001). Radiculopathy patients were more likely to achieve general MCID improvements following surgery (NDI: Odds ratio (OR): 1.42, p=.035 and VAS Arm: OR: 2.98, p<.001), but there was no difference between patients with radiculopathy or myelopathy when using radiculopathy and myelopathy specific MCID thresholds (MCS-12: p=.113, PCS-12: p=.675, NDI: p=.108, and VAS Arm: p=.314).CONCLUSIONSPatients undergoing ACDF with myelopathy or radiculopathy represent two distinct patient populations with differing treatment indications and clinical outcomes. Compared to radiculopathy, patients with myelopathy have better baseline function, decreased improvement in PROMs, and are less likely to reach MCID using general threshold values, but there is no difference in the proportion reaching MCID when using specific threshold values.LEVEL OF EVIDENCEIRB     

Validating the VR-12 Physical Function Instrument After Anterior Cervical Discectomy and Fusion with SF-12, PROMIS,and NDI

Background

Development and validation of Veterans RAND 12-item (VR-12) physical component survey (PCS) has been established among civilian and veteran populations but it has not been examined among anterior cervical discectomy and fusion (ACDF) patients.

Purposes/Questions

We sought to validate legacy patient-reported outcome measures (PROMs) with VR-12 PCS among patients undergoing ACDF procedures.

Methods

A prospectively collected surgical registry was retrospectively evaluated for elective single or multi-level ACDFs performed for degenerative spinal pathologies from January 2014 to August 2019. Exclusion criteria included missing pre-operative surveys and surgery for trauma, metastasis, or infection. Demographic variables, baseline pathologies, and peri-operative variables were collected. A paired t test evaluated the change from the pre-operative score to each post-operative timepoint for VR-12 PCS, the 12-item Short-Form Survey (SF-12) PCS, Patient-Reported Outcomes Measurement Information System physical function (PROMIS-PF), and Neck Disability Index (NDI). Minimal clinically important difference (MCID) achievement was calculated at each timepoint. Correlation was evaluated with a Pearson’s correlation coefficient and time-independent partial correlation.

Results

Of the 202 patients who underwent ACDF, 41.1% were female and the average age was 49.5 years. All PROMs had statistically significantly increased from baseline when compared with post-operative timepoints (12 weeks, 6 months, 1 year, and 2 years). MCID achievement rates increased through 2 years. All timepoints revealed strong VR-12 PCS correlations with SF-12 PCS, PROMIS-PF, and NDI scores.

Conclusion

VR-12 PCS was strongly correlated with the well-validated SF-12 PCS and NDI metrics as well as with the more recent PROMIS-PF. All PROMs demonstrated statistically significant improvement in patients post-operatively. VR-12 PCS is a valid measure of physical function among patients undergoing ACDF.

     

Usefulness of minimum clinically important difference for assessing patients with subaxial degenerative cervical spine disease: statistical versus substantial clinical benefit

Background

The measurement of the therapeutic outcome of cervical spine surgeries commonly relies on four main patient reported outcomes (PROs): Neck Disability Index (NDI), Visual Analog Scale (VAS) for pain, and Short Form-36 (SF-36) Physical (PCS) and Mental (MCS) Component Summary. However, the clinical impact of such scores and how they could effectively measure therapeutic efficacy remains unclear. In this context, the concept of minimum clinically important difference (MCID) is developing into the standard by which to evaluate treatments, patient satisfaction and cost-effectiveness.

Methods

Eighty-eight consecutive patients undergoing surgery for subaxial degenerative cervical spine disease were selected from a prospective blinded database. PROs (NDI, PCS, MCS and VAS) were collected preoperatively, and together with blinded Surgeon Ratings (SR) at 3 months and 6 months post-surgery. Four anchor-based approaches were used to calculate different MCIDs. Three anchors (VAS, HTI (Health Transition Item of the SF-36) and SR) were used to evaluate surgery outcome. The best clinically and statistically relevant MCID was chosen.

Results

On average, all patients presented with a statistically significant improvement (p?<?0.001) postoperatively for NDI (27.42 to 19.42), PCS (33.02 to 42.03), MCS (44 to 50.74) and VAS (2.85 to 1.93). The four MCID anchor-based approaches yielded a range of values for each PRO: 2.23–16.59 for PCS, 0.11–16.27 for MCS and 2.72–12.08 for NDI. When compared to the VAS and HTI anchors, the area under the ROC curve was greater for SR. This finding suggests that SR may be a more reliable anchor for MCID calculation.

Conclusion

The MDC (minimum detectable change) approach together with the SR anchor appears to be the most appropriate MCID method. It offers the greatest area under the ROC curve (threshold above the 95 % CI), and the choice of the anchor did not significantly affect this result. MCID values for this dataset were 5.6 for PCS, 5.12 for MCS and 2.41 for NDI.     

Neck Disability Index,short form-36 physical component summary,and pain scales for neck and arm pain: the minimum clinically important difference and substantial clinical benefit after cervical spine fusion

Background ContextThe Neck Disability Index (NDI), the short form-36 (SF-36) physical component summary (PCS), and pain scales for arm and neck pain are increasingly used to evaluate treatment effectiveness after cervical spine surgery. The minimum clinically important difference (MCID) is a threshold of improvement that is clinically relevant to the patient. However, the true goal is to provide the patient with a substantial clinical benefit (SCB).PurposeThis study determines the MCID and SCB using common anchor-based methods for NDI, PCS, and pain scales for arm and neck pain in patients undergoing cervical spine fusion for degenerative disorders.Study Design/SettingThe study setting is a longitudinal cohort in a multisurgeon spine specialty clinic.Patient sampleThe sample comprises 505 patients who underwent a cervical fusion for degenerative spine conditions and who have prospectively collected outcome scores with a minimum 1-year follow-up.Outcome MeasuresThe outcome measures of the study were NDI, SF-36, and numeric rating scales for arm and neck pain.MethodsThe MCID and SCB values for NDI, PCS, and pain scales for arm and neck pain were determined using receiver operating characteristic (ROC) curve analysis with the Health Transition Item of the SF-36 as an anchor. The Health Transition Item asks a patient “Compared to one year ago, how would you rate your health in general now?” with answers ranging from “Much Better,” “Somewhat Better,” “About the Same,” “Somewhat Worse,” to “Much Worse.” An ROC curve was constructed for each measure. The ROC curve–derived MCID was the change score with equal sensitivity and specificity to distinguish the “Somewhat Better” from the “About the Same” patients. The ROC curve–derived SCB was the change score with equal sensitivity and specificity to distinguish the “Much Better” from the “Somewhat Better” patients. Distribution-based methods including the standard error of the mean and the minimum detectable change were also used to calculate MCID.ResultsThe calculated MCID is 7.5 for the NDI, 4.1 for SF-36 PCS, and 2.5 for arm and neck pain. The calculated SCB is 9.5 for the NDI, 6.5 for SF-36 PCS, and 3.5 for arm and neck pain.ConclusionsPatients with an eight-point decrease in NDI, a 4.1-point increase in PCS, and a three-point decrease in arm or neck pain can detect a minimally clinically important change. Patients with a 10-point decrease in NDI, a 6.5-point increase in PCS, and a four-point decrease in arm or neck pain can detect an SCB after cervical spine fusion.     

The Impact of Total Hip Arthroplasty Surgical Approach on Patient-Reported Outcomes Measurement Information System Computer Adaptive Tests of Physical Function and Pain Interference

BackgroundThe present study examines Patient Reported Outcomes Measurement Information System (PROMIS) Computer Adaptive Test (CAT) scores for domains of physical function (PF) and pain interference (PI) in patients undergoing elective THA from either a direct anterior or posterior surgical approach.MethodsA total of 1358 patients who underwent THA at our institution from 1/1/2015 to 12/1/2018 were identified. Visual analog scale (VAS) pain scores, PROMIS CAT PF and PI data were collected at the last preoperative visit as well as 6 weeks, 6 months, and 1-2 years postoperatively. Literature-derived minimum clinically important difference (MCID) for PROMIS CAT PF metric with regard to THA was used for data comparison.ResultsFour hundred nine patients were included in the final analysis. Fifty-one percent underwent a posterior approach, and 49% underwent a direct anterior approach. Both approaches led to a significant improvement in PROMIS CAT PF and PI scores. Patients undergoing a direct anterior approach had significantly higher preoperative and postoperative PROMIS CAT PF scores as well as significantly lower preoperative PROMIS CAT PI scores. Each approach yielded similar interval improvements of PROMIS CAT PF and PI. One hundred three direct anterior approach THA patients (51%) and 119 posterior approach THA patients (57.5%) achieved PROMIS PF MCID at 1- to 2-year follow-up.ConclusionNeither the direct anterior nor posterior THA surgical approach conferred an advantage to postoperative improvements of PROMIS CAT PF and PI scores. Adult reconstructive surgeons should continue to execute the direct anterior or posterior THA surgical approaches based upon personal preference. Despite surgeon confidence in THA, the potential for further innovation exists given the number of THA patients who failed to achieve PROMIS PF MCID.     

Impact of gender on outcomes following single-level anterior lumbar interbody fusion

BackgroundThere have been a multitude of studies attempting to identify the relationship between gender and postoperative outcomes; however, few studies have examined how this relationship may affect outcomes after anterior lumbar interbody fusion (ALIF) surgery. We aim to better characterize the impact that self-reported gender may have on patient reported outcome measures (PROMs) and achievement rates of minimum clinically important difference (MCID) after ALIF.MethodsA retrospective database of a single spine surgeon was searched for patients who had undergone single-level ALIF. Indications for surgery including acute trauma, infection, or malignancy were excluded. The population was separated into cohorts by self-reported gender, female or male. PROMs were recorded and compared within groups to their preoperative baselines and between groups. MCID achievement rate was compared between groups.Results140 patients were identified for this study, with 68 patients self-identifying as female gender. The male gender cohort was found to have a significantly greater prevalence of hypertension (p = 0.018). Both cohorts showed significant improvement during at least one or more postoperative time points for each evaluated outcome measure (p ≤ 0.048, all). No significant difference in mean PROM scores was noted between cohorts at any time point for any measured outcome. The female gender cohort had significantly greater MCID achievement rates for visual acuity scale (VAS) back pain overall and at the 6-month time point (p ≤ 0.043, both). The female gender cohort also had significantly greater achievement of MCID at the 1-year time point for VAS leg pain (p = 0.017).ConclusionBoth female and male gender cohorts demonstrated significant improvement in all outcomes measured at one or more postoperative time points. Postoperative outcomes did not differ by gender. MCID achievement was more common in female patients. Female patients may experience more tangible clinical improvement after ALIF compared to male patients.     

Construct validity and responsiveness of commonly used patient reported outcome instruments in decompression for lumbar spinal stenosis

BackgroundValidity and responsiveness of Oswestry disability index (ODI), Roland Morris disability questionnaires (RMDQ), Short Form-12 Physical Component Score (SF-12 PCS) and Short Form-12 Mental Component Score (SF-12 MCS) in patients undergoing open decompression for lumbar canal stenosis has not been previously reported.MethodsOutcome assessment was prospectively evaluated using the ODI, RMDQ, SF-12 PCS and SF-12 MCS pre-intervention and at average follow-up of three months post-intervention. Pearson correlation coefficient was used to evaluate the association between change in values of ODI, RMDQ, SF-12 PCS and SF-12 MCS. Distribution based methods (Effect size [ES], standardised response mean [SRM]) and anchor based method (Area under the curve [AUC] of receiver operating curve [ROC]) were used to determine responsiveness. AUC value ≥ 0.70 is considered as adequate level of responsiveness and the outcome instrument with the largest AUC is considered to be the most responsive outcome instrument.ResultsThis study included 77 participants. Responsiveness was assessed at a mean follow-up of 12 weeks postoperatively. There was significant strong correlation between ODI and RMDQ (r = 0.65, p < 0.0001). The ES of ODI, RMDQ, SF-12 PCS and SF-12 MCS were 1.54, 1.48, 1.85 and 0.51 respectively. The SRM of RMDQ, ODI, SF-12 PCS and SF-12 MCS were 1.22, 1.17, 1.0 and 0.47 respectively. AUC of ODI, RMDQ, SF-12 PCS and SF-12 MCS were 0.83–0.88, 0.82 to 0.86, 0.78 to 0.81 and 0.69 to 0.70 respectively.ConclusionIt is recommended to use either ODI or RMDQ as region specific patient reported outcome instrument and SF-12 PCS as a health related quality of life outcome instrument to evaluate outcome after decompressive laminectomy for lumbar canal stenosis.     

Impact of preoperative weakness and duration of symptoms on health-related quality-of-life outcomes following anterior cervical discectomy and fusion

BACKGROUND CONTEXTThe majority of patients with preoperative upper extremity weakness show improvements in motor function after anterior cervical discectomy and fusion (ACDF). Although numerous studies have examined both the extent and time course to which motor function can be expected to improve, few have shown that these improvements in motor function translate to improved health related quality of life (HRQOL) outcomes.PURPOSEThe purpose of this study was to examine the effect of preoperative weakness and duration of symptoms on HRQOL outcomes in patients who underwent ACDF.STUDY DESIGNRetrospective cohort study.PATIENT SAMPLEAdult patients who underwent an ACDF procedure at an academic hospital from January 2015 to December 2016 by a fellowship-trained spine surgeon.OUTCOME MEASURESThe primary outcomes of interest were HRQOL outcomes: Short Form-12 Physical/Mental Component Scores (SF-12 PCS/MCS), Neck Disability Index (NDI), and Visual Analog Scale Arm/Neck scores (VAS Arm/Neck).METHODSPatient demographics, surgical case characteristics, and motor strength exams were collected in patients who underwent ACDF over a 2-year period. Preoperative weakness was defined by a strength grade ≤3 (on a scale from 0 to 5) in at least one upper extremity muscle group. Multivariate linear regression analysis was performed to determine the effect of the preoperative weakness on HRQOL outcomes.RESULTSOf the 276 patients identified, 45 (16.3%) showed evidence of preoperative weakness, 44 (97.8%) of which showed subsequent postoperative motor improvements after ACDF. All patients reported significant improvements in all HRQOL outcome measures. Patients with preoperative weakness reported significantly worse preoperative VAS Arm (6.9 vs. 5.2; p=.01) and VAS Neck (6.1 vs. 4.8; p=.02) pain scores. Compared with patients without preoperative weakness, those with preoperative weakness reported significantly more improvement in NDI (β: −10.9; p=.001). Patients with symptoms greater than or equal to 12 months and preoperative weakness showed significantly less improvement in NDI (β: 14.8; p=.03).CONCLUSIONSPatients with preoperative weakness generally exhibited worse pain and HRQOL measures preoperatively, and showed greater potential for improvement after ACDF. Patients with a shorter duration of preoperative weakness had greater potential for improvement in HRQOL measures after ACDF compared with those with longer duration of symptoms. ACDF is an effective procedure to improve strength and HRQOL measures across all patient groups under appropriate indications.     

Preoperative MRI predictors of health-related quality of life improvement after microscopic lumbar discectomy

BACKGROUNDLumbar herniated nucleus pulposus (HNP) is a common spinal pathology often treated by microscopic lumbar discectomy (MLD), though prior reports have not demonstrated which preoperative MRI factors may contribute to significant clinical improvement after MLD.PURPOSETo analyze the MRI characteristics in patients with HNP that predict meaningful clinical improvement in health-related quality of life scores (HRQoL) after MLD.STUDY DESIGN/SETTINGRetrospective clinical and radiological study of patients undergoing MLD for HNP at a single institution over a 2-year period.PATIENT SAMPLEEighty-eight patients receiving MLD treatment for HNP.OUTCOME MEASURESCephalocaudal Canal Migration; Canal & HNP Anterior-Posterior (AP) Lengths and Ratio; Canal & HNP Axial Areas and Ratio; Hemi-Canal & Hemi-HNP Axial Areas and Ratio; Disc appearance (black, gray, or mixed); Baseline (BL); and 3-month (3M) postoperative HRQoL scores.METHODSPatients >18 years old who received MLD for HNP with BL and 3M HRQoL scores of PROMIS (Physical Function, Pain Interference, and Pain Intensity), ODI, VAS Back, and VAS Leg scores were included. HNP and spinal canal measurements of cephalocaudal migration, AP length, area, hemi-area, and disc appearance were performed using T2 axial and sagittal MRI. HNP measurements were divided by corresponding canal measurements to calculate AP, Area, and Hemi-Area ratios. Using known minimal clinically important differences (MCID) for each ΔHRQoL score, patients were separated into two groups based on whether they reached MCID (MCID+) or did not reach MCID (MCID–). The MCID for PROMIS pain intensity was calculated using a decision tree. A linear regression illustrated correlations between PROMIS vs ODI and VAS Back/Leg scores. Independent t-tests and chi-squared tests were utilized to investigate significant differences in HNP measurements between the MCID+ and MCID– groups.RESULTSThere were 88 MLD patients included in the study (Age=44.6±14.9, 38.6% female). PROMIS pain interference and pain intensity were strongly correlated with ODI and VAS Back/Leg (R≥0.505), and physical function correlated with ODI and VAS Back/Leg (R=−0.349) (all p<.01). The strongest MRI predictors of meeting HRQoL MCID were gray disc appearance, HNP area (>116.6 mm²), and Hemi-Area Ratio (>51.8%). MCID+ patients were 2.7 times more likely to have a gray HNP MRI signal than a mixed or black HNP MRI signal in five out of six HRQoL score comparisons (p<.025). MCID+ patients had larger HNP areas than MCID– patients had in five out of six HRQoL score comparisons (116.6 mm²±46.4 vs 90.0 mm²±43.2, p<.04). MCID+ patients had a greater Hemi-Area Ratio than MCID– patients had in four out of six HRQoL score comparisons (51.8%±14.7 vs 43.9%±14.9, p<.05).CONCLUSIONSPatients who met MCID after MLD had larger HNP areas and larger Hemi-HNP Areas than those who did not meet MCID. These patients were also 2.7× more likely to have a gray MRI signal than a mixed or black MRI signal. When accounting for HNP area relative to canal area, patients who met MCID had greater Hemi-HNP canal occupation than patients who did not meet MCID. The results of this study suggest that preoperative MRI parameters can be useful in predicting patient-reported improvement after MLD.     

Are Oxford Hip Score and Western Ontario and McMaster Universities Osteoarthritis Index Useful Predictors of Clinical Meaningful Improvement and Satisfaction After Total Hip Arthroplasty?

BackgroundUp to 15% of patients express dissatisfaction after total hip arthroplasty (THA). Preoperative patient-report outcome measures (PROMs) scores can potentially mitigate this by predicting postoperative satisfaction, identifying patients that will benefit most from surgery. The aim of this study was to (1) calculate the minimal clinically important difference (MCID) thresholds for Oxford Hip Score (OHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Short Form-36 (SF-36) mental component summary (MCS) and physical component summary (PCS) scores and (2) identify the threshold values of these PROMs that could be used to predict patient satisfaction and expectation fulfilment.MethodsProspectively collected registry data of 1334 primary THA patients who returned for 2-year follow-up from 1998 to 2016 were reviewed. All patients were assessed preoperatively and postoperatively at 2 years using the OHS, WOMAC, and SF-36 PCS/MCS scores. The MCID for each PROMs was calculated, and the proportion of patients that attained MCID was recorded. The relationship between satisfaction, expectation fulfilment, and MCID attainment was analyzed using Spearman rank correlation. Optimal threshold scores for each PROM that predicted MCID attainment and satisfaction/expectation fulfilment at 2 years were calculated using receiver operating curve analysis.ResultsThe calculated MCID for OHS, WOMAC, SF-36 PCS, and SF-36 MCS were 5.2, 10.8, 6.7, and 6.2, respectively. A threshold value of 24.5 for the preoperative OHS was predictive of achieving WOMAC MCID at 2 years after THA (area under the curve 0.80, P < .001). 93.1% of patients were satisfied, and 95.5% had expectations fulfilled at 2 years. None of the PROMs were able to predict satisfaction.ConclusionOHS and WOMAC scores can be used to determine clinical meaningful improvement but are limited in their ability to predict patient satisfaction after THA.     

Determination of minimum clinically important difference (MCID) in pain,disability, and quality of life after revision fusion for symptomatic pseudoarthrosis

Background contextSpinal surgical outcome studies rely on patient reported outcome (PRO) measurements to assess the effect of treatment. A shortcoming of these questionnaires is that the extent of improvement in their numerical scores lacks a direct clinical meaning. As a result, the concept of minimum clinically important difference (MCID) has been used to measure the critical threshold needed to achieve clinically relevant treatment effectiveness. Post hoc anchor-based MCID methods have not been applied to the surgical treatment for pseudoarthrosis.PurposeTo determine the most appropriate MCID values for visual analog scale (VAS), Oswestry Disability Index (ODI), Short Form (SF)-12 physical component score (PCS), and European Quality of Life 5-Dimensions (EQ-5D) in patients undergoing revision lumbar arthrodesis for symptomatic pseudoarthrosis.Study design/ settingRetrospective cohort study.MethodsIn 47 patients undergoing revision fusion for pseudoarthrosis-associated back pain, PRO measures of back pain (BP-VAS), ODI, physical quality of life (SF-12 PCS), and general health utility (EQ-5D) were assessed preoperatively and 2 years postoperatively. Four subjective post hoc anchor-based MCID calculation methods were used to calculate MCID (average change; minimum detectable change; change difference; and receiver operating characteristic curve analysis) for two separate anchors (health transition index (HTI) of SF-36 and satisfaction index).ResultsAll patients were available for a 2-year PRO assessment. Two years after surgery, a significant improvement was observed for all PROs; Mean change score: BP-VAS (2.3±2.6; p<.001), ODI (8.6%±13.2%; p<.001), SF-12 PCS (4.0±6.1; p=.01), and EQ-5D (0.18±0.19; p<.001). The four MCID calculation methods generated a wide range of MCID values for each of the PROs (BP-VAS: 2.0–3.2; ODI: 4.0%–16.6%; SF-12 PCS: 3.2–6.1; and EQ-5D: 0.14–0.24). There was no difference in response between anchors for any patient, suggesting that HTI and satisfaction anchors are equivalent in this patient population. The wide variations in calculated MCID values between methods precluded any ability to reliably determine what the true value is for meaningful change in this disease state.ConclusionsUsing subjective post hoc anchor-based methods of MCID calculation, MCID after revision fusion for pseudoarthrosis varies by as much as 400% per PRO based on the calculation technique. MCID was suggested to be as low as 2 points for ODI and 3 points for SF-12. These wide variations and low values of MCID question the face validity of such calculation techniques, especially when applied to heterogeneous disease and patient groups with a multitude of psychosocial confounders such as failed back syndromes. The variability of MCID thresholds observed in our study of patients undergoing revision lumbar fusion for pseudoarthrosis raises further questions to whether ante hoc or Delphi methods may be a more valid and consistent technique to define clinically meaningful, patient-centered changes in PRO measurements.     

What is the role of dynamic cervical spine radiographs in predicting pseudarthrosis revision following anterior cervical discectomy and fusion?

Background ContextPostoperative dynamic radiographs are used to assess fusion status after anterior cervical discectomy and fusion (ACDF) with comparable accuracy to computed tomography (CT) scans.PurposeTo (1) determine if dynamic radiographs accurately predict pseudarthrosis revision in a cohort of largely asymptomatic patients who underwent ACDF, (2) determine how adjacent segment motion is affected by fusion status, and (3) analyze how clinical outcomes differ between patients with symptomatic and asymptomatic pseudarthrosis.Study DesignRetrospective cohort study.Patient SamplePatients ≥ 18 years who underwent primary one- to four-level ACDF at a single institution over a 10-year period.Outcome MeasuresInterspinous motion on preoperative and postoperative flexion-extension radiographs and preoperative and postoperative Visual Analogue Scale for Neck Pain (VAS Neck) and Arm Pain (VAS Arm), Neck Disability Index (NDI), Modified Japanese Orthopaedic Association scale (mJOA), Mental and Physical Component Scores of the Short-Form 12 (SF-12) Health Survey (MCS-12 and PCS-12)MethodsThe difference in spinous process motion between flexion and extension radiographs was used to determine motion at each level of the ACDF construct. Pseudarthrosis was defined as ≥ 1 mm spinous process motion on dynamic radiographs. A receiver operating characteristic (ROC) curve was generated to predict the probability of surgical revision for pseudarthrosis based on millimeters of interspinous motion at each instrumented level. Patient reported outcome measures (PROMs) were used to assess the effect of pseudarthrosis on clinical outcomes. Alpha was set at p<.05.ResultsA total of 597 patients met inclusion criteria including 1,203 ACDF levels. Of those, 215 patients (36.0%) were diagnosed with a pseudarthrosis on dynamic radiographs with 29 patients (4.9%) requiring pseudarthrosis revision. ROC analysis identified a “cutoff” value of 1.00 mm of interspinous process motion for generating an optimal area under the curve (AUC). The negative predictive value (NPV) was 99.6%, whereas the positive predictive value (PPV) was 13.7%. When analyzing adjacent segment motion, the Δ supra-adjacent interspinous process motion (ISM) was significantly lower for patients with a superior construct pseudarthrosis (-1.06 mm vs. 1.80 mm, p<.001), whereas the Δ infra-adjacent level ISM was significantly lower for patients with an inferior construct pseudarthrosis (-1.21 mm vs. 2.15 mm, p<.001). Patients with a pseudarthrosis not requiring revision had worse postoperative NDI (29.3 vs. 23.4, p=.027), VAS Neck (3.40 vs. 2.63, p=.012), and VAS Arm (3.09 vs. 1.85, p=.001) scores at 3 months, but not 1-year, compared with patients who were fused. Patients requiring pseudarthrosis revision had higher 1-year postoperative NDI (38.0 vs. 23.7, p=.047) and lower 1-year postoperative Δ VAS Arm (-0.22 vs. -2.97, p=.016) scores.ConclusionsOne-year postoperative dynamic radiographs have a greater than 99% negative predictive value for identifying patients requiring pseudarthrosis revision, but they have a low positive predictive value. Most patients with a pseudarthrosis remain asymptomatic with similar 1-year postoperative patient-reported outcomes compared with patients without a pseudarthrosis.     

The association of comorbidity indices and minimal clinically important difference in a population undergoing shoulder arthroplasty

BackgroundShoulder arthroplasty (SA) procedures are increasingly common. The Charlson and Elixhauser indices are ICD-10 based measures used in large databases to describe the patient case mix in terms of secondary medical conditions. There is a paucity of data on the relationship between these indices and patient-reported outcome measures (PROMs) after shoulder arthroplasty.MethodsPatients undergoing SA from 2016-2018 were identified in the electronic medical records. Charlson and Elixhauser comorbidities were used to calculate comorbidity scores according to established algorithms (eg Elixhauser-Walraven). Patient shoulder-specific (American Shoulder and Elbow Surgeons (ASES) score and Shoulder Activity Scale (SAS)) and general health scales (SF-12 Mental Component Score (MCS) and Physical Component Score (PCS) and Patient-Reported Outcomes Measurement Information System-Pain Interference (PROMIS-PI)) PROMs were obtained from our institution’s shoulder registry. Linear regression models adjusting for age and sex evaluated associations between comorbidity scores and PROMs. Receiver operating characteristic (ROC) curves determined optimal cutoffs, maximizing sensitivity and specificity to identify patients likely to fail to meet minimal clinically important difference (MCID) values.ResultsA total of 1817 SA procedures were identified. Higher Charlson and Elixhauser-Walraven scores were significantly associated with lower baseline SAS and SF-12 PCS. Patients with higher Charlson scores had lower baseline ASES (P = .003) and lower baseline (P = .0002) and 2-year (P = .02) SF-12 MCS. No significant associations were found for PROMIS-PI with either index. The Charlson score better predicted the failure to meet MCID for SF-12 PCS with an AUC of 0.64, compared to 0.55 for Elixhauser-Walraven. Conversely, Elixhauser-Walraven better predicted PROMIS-PI with an AUC of 0.66, compared to 0.53 for Charlson. Moderate AUCs were observed for the remaining PROMs, ranging from 0.57-0.64, with little difference between index scores.ConclusionHigher Charlson and Elixhauser-Walraven scores were associated with lower baseline scores on most PROMs. Generally, the Charlson score performed better than the Elixhauser-Walraven score in predicting worse outcomes at 2 years. Comorbidity indices may be useful as a decision aid to provide appropriate expectations of outcomes for patients undergoing SA.     

Practical answers to frequently asked questions in minimally invasive lumbar spine surgery

BACKGROUND CONTEXTSurgical counseling enables shared decision-making (SDM) by improving patients’ understanding.PURPOSETo provide answers to frequently asked questions (FAQs) in minimally invasive lumbar spine surgery.STUDY DESIGNRetrospective review of prospectively collected data.PATIENT SAMPLEPatients who underwent primary tubular minimally invasive lumbar spine surgery in form of transforaminal lumbar interbody fusion (MI-TLIF), decompression alone, or microdiscectomy and had a minimum of 1-year follow-up.OUTCOME MEASURES(1) Surgical (radiation exposure and intraoperative complications) (2)Immediate postoperative (length of stay [LOS] and complications) (3) Clinical outcomes (Visual Analog Scale- back and leg, VAS; Oswestry Disability Index, ODI; 12-Item Short Form Survey Physical Component Score, SF-12 PCS; Patient-Reported Outcomes Measurement Information System Physical Function, PROMIS PF; Global Rating Change, GRC; return to activities; complications/reoperations)METHODSThe outcome measures were analyzed to provide answers to ten FAQs that were compiled based on the authors’ experience and a review of literature. Changes in VAS back, VAS leg, ODI, and SF-12 PCS from preoperative values to the early (<6 months) and late (>6 months) postoperative time points were analyzed with Wilcoxon Signed Rank Tests. % of patients achieving minimal clinically important difference (MCID) for these patient-reported outcome measures (PROMs) at the two time points was evaluated. Changes in PROs from preoperative values too early (<6 months) and late (≥6 months) postoperative time points were analyzed within each of the three groups. Percentage of patients achieving MCID was also evaluated.RESULTSThree hundred sixty-six patients (104 TLIF, 147 decompression, 115 microdiscectomy) were included. The following FAQs were answered: (1) Will my back pain improve? Most patients report improvement by >50%. About 60% of TLIF, decompression, and microdiscectomy patients achieved MCID at ≥6 months. (2) Will my leg pain improve? Most patients report improvement by >50%. 56% of TLIF, 67% of decompression, and 70% of microdiscectomy patients achieved MCID at ≥6 months. (3) Will my activity level improve? Most patients report significant improvement. Sixty-six percent of TLIF, 55% of decompression, and 75% of microdiscectomy patients achieved MCID for SF-12 PCS. (4) Is there a chance I will get worse? Six percent after TLIF, 14% after decompression, and 5% after microdiscectomy. (5) Will I receive a significant amount of radiation? The radiation exposure is likely to be acceptable and nearly insignificant in terms of radiation-related risks. (6) What is the likelihood that I will have a complication? 17.3% (15.4% minor, 1.9% major) for TLIF, 10% (9.3% minor and 0.7% major) for decompression, and 1.7% (all minor) for microdiscectomy (7) Will I need another surgery? Six percent after TLIF, 16.3% after decompression, 13% after microdiscectomy. (8) How long will I stay in the hospital? Most patients get discharged on postoperative day one after TLIF and on the same day after decompression and microdiscectomy. (9) When will I be able to return to work? >80% of patients return to work (average: 25 days after TLIF, 14 days after decompression, 11 days after microdiscectomy). (10) Will I be able to drive again? >90% of patients return to driving (average: 22 days after TLIF, 11 days after decompression, 14 days after microdiscectomy).CONCLUSIONSThese concise answers to the FAQs in minimally invasive lumbar spine surgery can be used by physicians as a reference to enable patient education.     

Correlation of mJOA,PROMIS physical function,and patient satisfaction in patients with cervical myelopathy: an analysis of the Michigan Spine Surgery Improvement Collaborative (MSSIC) database

BACKGROUND CONTEXTPatient-reported outcomes (PROs) are increasingly utilized to evaluate the efficacy and value of spinal procedures. Among patients with cervical myelopathy, the modified Japanese Orthopaedic Association (mJOA) remains the standard instrument, with Patient-Reported Outcomes Measurement Information System (PROMIS) physical function (PF) and patient satisfaction also frequently assessed. These outcomes have not all been directly compared using a large spine registry at 2 years follow-up for cervical myelopathic patients undergoing surgery.PURPOSETo determine the correlation and association of PROMIS PF, mJOA, and patient satisfaction outcomes in patients undergoing surgery for cervical myelopathy.STUDY DESIGN/SETTINGRetrospective review of a multicenter spine registry database.PATIENT SAMPLEAdult patients with cervical myelopathy who underwent cervical spine surgery between 2/26/2018 and 4/17/2021.OUTCOME MEASURESPROMIS PF, mJOA, and North American Spine Society (NASS) patient satisfaction index.METHODSThe MSSIC database was accessed to gather pre- and postoperative outcome data on patients with cervical myelopathy. Spearman's correlation coefficients relating mJOA and PROMIS PF were quantified up to 2 years postoperatively. The correlations between patient satisfaction with mJOA and PROMIS were determined. Kappa statistics were used to evaluate for agreement between those reaching the minimum clinically important difference (MCID) for mJOA and PROMIS PF. Odds ratios were calculated to determine the association between patient satisfaction and those reaching MCID for mJOA and PROMIS PF. Support for MSSIC is provided by BCBSM and Blue Care Network as part of the BCBSM Value Partnerships program.RESULTSData from 2,023 patients were included. Moderate to strong correlations were found between mJOA and PROMIS PF at all time points (p<.001). These outcomes had fair agreement at all postoperative time points when comparing those who reached MCID. Satisfaction was strongly related to changes from baseline for both mJOA and PROMIS PF at all time points (p<.001). Odds ratios associating satisfaction with PROMIS PF MCID were higher at all time points compared with mJOA, although the differences were not significant.CONCLUSIONSPROMIS PF has a strong positive correlation with mJOA up to 2 years postoperatively in patients undergoing surgery for cervical myelopathy, with similar odds of achieving MCID with both instruments. Patient satisfaction is predicted similarly by these outcome measures by 2 years postoperatively. These results affirm the validity of PROMIS PF in the cervical myelopathic population. Given its generalizability and ease of use, PROMIS PF may be a more practical outcome measure for clinical use compared with mJOA.