Foot and Ankle Clinic Application for Liposomal Related Anesthetic: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Foot and Ankle Clinic Application for Liposomal Related Anesthetic (NCT02586077), a na phase 4 study. The primary outcome is Amount of Narcotic Use.

2. Clinical Question

The study also listed pain on a Visual Analog Scale from 0 to 10, anti-emetic use, a patient satisfaction questionnaire about postsurgical pain relief, and the number of patients with postoperative complications as secondary outcomes. These outcomes broaden the questions beyond medication consumption, but their results are not reported in the registry record. In particular, the record does not give the mean narcotic-use value, the full range, or a statistical comparison. The clinical question is therefore identifiable, while the evidence needed to answer it from the registry results is absent.

3. Trial Design

This is a completed Phase 4 study with a single-group model and enrollment of 36. The registry lists allocation as NA and masking as none. It does not report a parallel control arm, random assignment, or masking. Accordingly, the design describes participants receiving the study regimen, rather than a randomized comparison of Exparel with a distinct treatment condition.

The listed conditions are ankle arthrodesis, hindfoot arthrodesis, and tibitalocalceal arthrodesis. For the Exparel group, participants received a single-shot popliteal block identified as standard of care and underwent their standardized procedure. At the conclusion of the case, the regimen was 20cc Exparel with 10cc normal saline. Further details about how the procedures were standardized, the timing or conduct of outcome assessments, and participant eligibility are not reported in the registry record.

The primary outcome was the amount of narcotic use in mg, measured from surgery to postoperative day 3. Its description specifies total morphine milligram equivalence across narcotic pain medications administered during that interval, with the mean and full range designated as the summary. Four secondary outcomes are listed: Visual Analog Scale of Pain (0-10), anti-emetic use, patient satisfaction regarding postsurgical pain relief, and the number of patients with postoperative complications. The record lists five outcome measures overall, but no analyses are listed.

The study is marked completed. The recorded start date is 2014-02-01 and the primary completion date is 2016-06-30. OrthoCarolina Research Institute, Inc. is identified as the sponsor. The registry record does not report a protocol-based sample-size justification, a control-group plan, or details that would clarify how results were intended to be compared or modeled. The single-group structure is central to interpretation: an observed outcome among treated participants would describe their experience, but by itself would not establish what would have happened under another treatment condition.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

Reasons for not completing this period:

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

Population: Patients completing study

6. Primary Endpoint

The registry lists the primary outcome as Amount of Narcotic Use, measured over Surgery to post operative day 3.

The primary endpoint concerns narcotic medication administered between surgery and postoperative day 3. The record defines the amount as total morphine milligram equivalence dosing across all narcotic pain medications given during that interval. Expressing different narcotic medications in morphine milligram equivalence provides a common scale for summarizing medication use. The endpoint is reported in mg, with the mean and full range specified.

Medication consumption is one way to describe postoperative analgesic care: it records medication administered, rather than asking participants only to rate pain. The registry’s study summary states that the purpose was to review surgeon-applied liposomal-release anesthetic for postoperative analgesia and that the hypothesis concerned the impact on immediate and 72-hour narcotic use. The primary endpoint’s interval extends from surgery through postoperative day 3, giving a defined period for the medication-use measure.

General statistical context: a mean describes the arithmetic average of observed values, while a full range gives the lowest and highest observed values. Medication-use data can vary substantially across participants, so the mean alone may not describe the spread or shape of the observations; the range gives limited information about extremes but not the overall distribution. No endpoint value, range, participant-level data, or uncertainty estimate is reported in the registry record. The intended measure is clear, but its observed magnitude and precision cannot be assessed from the posted results.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry record describes a single-group study and identifies mean narcotic use as the primary outcome summary, with a full range. It lists no analyses. It does not report a statistical analysis plan, a test for the primary endpoint, an adjustment model, or the handling of incomplete observations. Statistical interpretation should therefore distinguish the outcome definition from methods that are not documented.

What does a mean describe?

General statistical explanation: a mean is the arithmetic average of observations. For a medication-use endpoint, it would summarize the average morphine milligram equivalence across participants with usable observations for the defined interval. A mean can be influenced by unusually high or low values, and it does not show how values are distributed around the center. The specified full range complements the mean by identifying the observed extremes, but does not reveal whether most participants had similar values or whether the distribution was strongly uneven. The registry does not report the actual mean or range.

Why express use as morphine milligram equivalence?

General statistical explanation: when an outcome includes multiple medications, translating doses to a common equivalence scale allows the total to be represented in a single unit. The registry defines its endpoint as total morphine milligram equivalence dosing across narcotic pain medications administered between surgery and postoperative day 3. That definition tells readers what the endpoint is intended to combine. The record does not provide the medication-level observations or conversion details, so those cannot be independently reviewed from the posted results.

What can a single-group analysis establish?

General statistical explanation: a single-group summary can describe observed outcomes in the group, but does not directly estimate a contrast with a separate treatment group. A comparison requires outcomes under two conditions and a method for evaluating their difference. Even when a study reports before-and-after observations, interpretation depends on the timing and analysis; such a design is not described. The registry identifies a single group, no masking, and no allocation to different arms. It does not report a comparator or an inferential analysis. The design therefore does not support a randomized treatment comparison in the registry record.

The regimen also included a single-shot popliteal block described as standard of care, alongside the study anesthetic. Any outcome summary would describe the overall care context as recorded, not the isolated contribution of one component. Without a distinct comparator condition, the registry information cannot separate the effects of the anesthetic from the block, the procedure, or other aspects of postoperative care.

What does precision mean?

General statistical explanation: an estimate of an average is subject to sampling variation. A confidence interval is one way to express uncertainty around an estimate under a specified model and procedure. Its width depends on factors including variation in observations and the amount of information available. A narrow interval indicates more precision than a wide interval, but precision does not correct bias or create a missing comparison. The registry record does not report a confidence interval, standard error, or other uncertainty measure for narcotic use.

The record specifies a mean and full range, but it does not say that a formal test, interval estimate, or model was used. No p-value or adjusted estimate is reported. It would be inappropriate to infer a test from the fact that the study summary includes a hypothesis. A hypothesis statement describes an expectation; it is not evidence that a statistical test was conducted or that the results supported the expectation.

How should planning calculations be distinguished from study results?

General statistical explanation: a sample-size planning calculation estimates how many participants might be needed under stated assumptions for a proposed comparison. Such a calculation is not an observed outcome and is not a measure of the probability that a completed study found a true effect. Any planning illustration associated with this record is described as based on an observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the target effect expressed as a stated fraction of the observed effect. The record identifies this as a planning illustration, not the trial’s own design. Its equal-allocation, two-arm assumptions do not describe the registered single-group study.

General statistical explanation: power is a design property calculated under assumptions about an effect, variation, allocation, and analysis. It is not a post-study measure of whether a result is true. An illustration based on a fraction of an observed effect is conditional on that assumed effect and should not be interpreted as observed power. No planning values or trial-specific sample-size justification are reported in the registry record. Enrollment of 36 is a recorded study characteristic, not proof that the study was adequately sized for a particular analysis.

More broadly, statistical methods must be interpreted in relation to the population analyzed, the endpoint definition, missing observations, and the design. The registry provides an endpoint window and outcome summary but does not report analysis populations, missing-data procedures, or an inferential plan. These omissions prevent assessment of whether a particular statistical method was appropriate or how the listed outcomes were handled.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists five outcome measures: amount of narcotic use as the primary outcome, plus pain on a Visual Analog Scale, anti-emetic use, patient satisfaction regarding postsurgical pain relief, and postoperative complications. It lists zero analyses. No multiplicity strategy, hierarchy among secondary outcomes, or adjustment for testing multiple outcomes is reported in the registry record.

General statistical explanation: when several outcomes or hypotheses are assessed, the chance of at least one apparently unusual result can increase if each is tested separately. A prespecified hierarchy or multiplicity adjustment can help clarify how results should be interpreted. The registry’s outcome list alone does not establish which outcomes were analyzed, whether any statistical tests were conducted, or how multiple tests were handled. Since no analyses or results are listed, the presence or consequences of multiplicity cannot be evaluated.

Missing-data handling and analysis populations are also not reported in the registry record. The record does not state how many participants contributed data to each outcome, whether any observations were incomplete, or how incomplete data would have been treated. It does not identify an intention-to-treat, per-protocol, or other analysis population. These details matter because the number and characteristics of participants included in an analysis can affect its interpretation. Enrollment of 36 does not establish that all 36 contributed to every outcome.

No protocol-based sample-size justification or interim-analysis plan is reported in the registry record. A planning illustration based on a fraction of an observed effect is not the same as the study’s design justification, and it does not answer how missing observations or multiple outcomes were addressed. Without analysis details and posted results, neither selective availability of outcomes nor the robustness of the reported endpoint can be assessed.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: increased pain (2.8%).

The safety record lists an overall group with 36 participants at risk for serious events and one participant affected, and 36 at risk for other events and one affected. It reports zero deaths. Increased pain is listed among the top serious terms at 2.8%. These figures are registry entries; the record does not provide event narratives or further clinical detail.

General statistical explanation: an event count describes how many participants were recorded as affected within the reported group, while the at-risk count gives the stated group size for that category. These entries do not by themselves establish whether an event was caused by the intervention. The registry record does not report timing, severity details beyond the serious-event classification, duration, management, or an investigator assessment of relatedness. Nor does it provide a comparator group against which to evaluate event frequency.

The serious and other event categories should be read as separately reported entries. The record does not clarify whether affected participants overlapped across categories, so their counts should not be combined to infer a total number of distinct participants. The 2.8% value is reported for the serious term increased pain; additional detail on how that term was coded is not reported in the registry record. Zero deaths means no deaths are recorded in this entry, not that every possible safety concern was excluded.

12. What the Result Does, and Does Not, Mean

The registry establishes that a completed Phase 4, single-group study with enrollment of 36 evaluated a surgeon-applied Exparel regimen after specified arthrodesis procedures. The primary outcome was mean total morphine milligram equivalence for narcotic medications administered from surgery through postoperative day 3, summarized with a full range. The registry also identifies four secondary outcomes and records limited safety counts. These registry entries describe the intended questions and the study setting.

What the record does not establish is the observed amount of narcotic use, the range of participant values, or whether any secondary outcome changed in a particular direction. No outcome results or analyses are reported. The registry therefore does not provide an estimate of the size or precision of any observed result, and the study’s stated hypothesis cannot be assessed from the posted results. The completion status is not itself evidence that the outcome supported the hypothesis.

The absence of a separate comparator also sets a limit on causal interpretation. A summary of outcomes among participants receiving the regimen would not show what their outcomes would have been under another condition. The regimen included a popliteal block described as standard of care as well as Exparel and normal saline at the conclusion of the case. Without a comparison group, the registry information cannot distinguish the contribution of these elements or other differences in care.

General statistical explanation: statistical uncertainty and design limitations address different questions. An interval estimate can describe uncertainty about a measured quantity under assumptions, but does not resolve the lack of a comparator. Conversely, a comparator does not make missing outcome data interpretable. Here, the primary result and its uncertainty are not reported, and the design is single-group.

The safety entries record one serious event, one other event, and zero deaths, with increased pain listed among the top serious terms at 2.8%. These figures do not identify causal relationships or provide enough detail to make broader conclusions about safety. Overall, the record describes a clinical question and an intervention regimen, but does not contain the outcome results needed to quantify what participants experienced or to compare that experience with an alternative.

13. Why This Trial Matters Statistically

This study is statistically notable because its primary question is comparative in spirit—the summary hypothesizes that surgeon-applied liposomal anesthetic would affect narcotic use—while the registered design is single-group. That distinction is important for clinical researchers. A clearly defined outcome does not, by itself, make a treatment effect identifiable. Without a distinct comparison condition, observed medication use would describe the treated group, but would not estimate the difference attributable to the intervention.

The endpoint definition is also concrete: total morphine milligram equivalence across narcotic medications from surgery to postoperative day 3, expressed as a mean and full range. This makes the intended measurement window and summary understandable. At the same time, the registry record does not report the measured value, the range, or an analysis. This illustrates why registration of outcomes and reporting of results are separate parts of the evidence record.

The study also lists outcomes that capture different aspects of postoperative experience: pain ratings, anti-emetic use, satisfaction, and complications. They do not substitute for one another; each addresses a distinct measurement question. Since no analyses or results are reported, the record does not show how any of these outcomes were observed or interpreted. The listed outcomes and zero listed analyses make clear that outcome definitions alone cannot support a statistical conclusion.

Finally, the record distinguishes safety counts from causal evidence. Counts and at-risk totals provide basic descriptive information, while the lack of event narratives, relatedness assessment, and a comparator constrains interpretation. General statistical lesson: design, outcome measurement, analysis, and complete reporting work together. A completed study and a stated hypothesis are not enough to determine an effect when the results and analysis are not reported. This record therefore highlights the need to read the design and results together rather than treating an endpoint definition as an outcome finding.

14. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

Several trial-specific limitations constrain interpretation. The study is recorded as single-group, with allocation listed as NA and masking as none. No distinct control condition is reported. Even if outcome measurements were available, this structure would limit direct comparisons and would not isolate the contribution of Exparel from the other care described in the record.

The intervention included a single-shot popliteal block described as standard of care, the standardized procedure, and 20cc Exparel with 10cc normal saline at the conclusion of the case. The record does not provide enough detail about the procedures or other postoperative care to evaluate how consistent care was across participants. It also does not report participant eligibility criteria or baseline characteristics, limiting assessment of who the findings would describe.

Most importantly, the registry record does not report the primary or secondary outcome results, and it lists zero analyses. There is no reported mean or full range for narcotic use, no account of outcome-specific participant counts, and no uncertainty estimate. Missing-data handling, analysis populations, and the statistical analysis plan are not reported in the registry record. These omissions prevent review of the analysis and its precision.

The record lists 36 participants at risk in the safety entries, but does not provide detailed event narratives or relatedness assessments. The listed serious-event term does not resolve whether an event was caused by the intervention. The registry also does not report a protocol-based sample-size justification or interim-analysis plan. A planning illustration using two arms does not describe the single-group design. Together, these limits mean that the registry information is useful for identifying the study question, regimen, and reported safety counts, but insufficient for estimating treatment effects or evaluating the primary hypothesis.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Foot and Ankle Clinic Application for Liposomal Related Anesthetic — NCT02586077.
• Registry record last updated 2020-10-29; status last verified 2020-10.
• Results first posted 2020-10-29.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

18. Record Summary

NCT02586077 is a completed Phase 4, single-group study sponsored by OrthoCarolina Research Institute, Inc. It enrolled 36 participants with ankle arthrodesis, hindfoot arthrodesis, or tibitalocalceal arthrodesis. The recorded start date is 2014-02-01 and the primary completion date is 2016-06-30.

Participants received a single-shot popliteal block described as standard of care and, at the conclusion of the case, 20cc Exparel and 10cc normal saline. The primary outcome was mean narcotic use in mg from surgery through postoperative day 3, defined as total morphine milligram equivalence across narcotic medications. Four secondary outcomes are listed, covering pain, anti-emetic use, satisfaction, and postoperative complications.

The registry record lists zero analyses and does not report outcome results. It reports one serious event, one other event, and zero deaths among 36 at risk in each category; increased pain is listed among the top serious terms at 2.8%. The design and absent outcome reporting do not support a comparative treatment-effect conclusion.