This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Foot and Ankle Post-operative Oedema Management Using Geko™ (NCT04927234), a randomized na study. The primary outcome is Assessment of Post-operative Oedema Formation Using the Figure-of-eight Tape Measurement.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04927234 |
| Phase | NA |
| Condition | Surgery, Edema |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 123 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Firstkind Ltd |
| Results posted | Yes |
2. Clinical Question
Population
The trial concerned patients undergoing foot and/or ankle surgery. The primary-outcome analysis used a modified intention-to-treat population: randomized subjects were included only if they attended both baseline and the Day 14 post-operative visit. Subjects who did not complete both visits were excluded from that analysis. The registry record does not report the characteristics of the analyzed population or how many randomized subjects met this requirement.
Intervention
The intervention was geko™ therapy added to standard care. The record describes application to the operated leg immediately after surgery, with use 24 hours / day while the patient remained in hospital. The description of the later schedule is incomplete in the registry record, so its duration and exact routine cannot be established from the record.
Comparator
The comparator was standard care as practiced at the hospital. The record does not specify a uniform care protocol across hospitals. The comparison is therefore between the randomized care strategies as described, rather than between geko™ therapy and no post-operative care.
Primary question
The primary question was whether adding geko™ therapy affected post-operative oedema, assessed using the figure-of-eight tape measurement. Measurements were specified at baseline, Day 14, Day 42, and Day 90 post-op. The primary outcome was described as a mean continuous measurement in cm, with standard error as the dispersion measure. Numerical group results and an estimated between-group contrast are not reported in the registry record, so the direction and precision of any difference cannot be assessed from the record.
3. Trial Design
This was a completed, multicentre, randomized, parallel-group trial with no masking. The registry record lists an enrollment of 123 and identifies Firstkind Ltd as the sponsor. The trial began on 2022-10-07, and primary completion was recorded as 2024-07-09. The phase is listed as NA. The study concerned post-operative oedema management in people undergoing foot and/or ankle surgery.
Randomization assigned patients on a 1:1 basis to standard care or standard care plus geko™ therapy. The intervention was a device. In the intervention arm, therapy was to be applied to the operated leg immediately after surgery. The record specifies use 24 hours / day while patients remained in hospital. Its account of treatment after the hospital stay ends mid-description, so the later schedule cannot be fully characterized from the registry record. The comparator group received standard care according to hospital practice.
The stated follow-up period was up to three months after surgery. The primary endpoint was assessed by figure-of-eight tape measurement at baseline and the named post-operative visits. Other listed outcome areas included adverse events, device deficiencies, pain measured with a visual analogue scale, surgical wound healing, analgesia use, and patient-reported outcomes using the Manchester-Oxford Foot & Ankle Questionnaire. The registry record lists 10 outcome measures and four analyses, but does not describe the full analysis plan or report numerical results for the primary endpoint.
Random allocation can support a fair comparison when assignment is preserved and follow-up and analysis are handled appropriately. However, the open-label design means participants and clinical teams were not masked to treatment assignment. The registry record does not report how randomization was generated or concealed, nor whether outcome assessors were masked.
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.
Before assignment: 123 participants consented- 6 screening failures, 5 withdrew consent prior to randomisation, 1 cancelled surgery post randomisation
Overall Study
| Stage | Standard of Care + Geko™ Therapy | Standard of Care |
|---|---|---|
| STARTED | 58 | 53 |
| COMPLETED | 43 | 35 |
| NOT COMPLETED | 15 | 18 |
Analysis population for the primary outcome, as defined in the registry: For this trial, a modified Intention-to-Treat (mITT) population was used, including only randomised subjects who attended both baseline and FU1 (day 14 post-operative) visits. Any randomised subjects who did not complete these visits were excluded from the analysis.
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.
| Characteristic | Unit | Standard of Care + Geko™ Therapy | Standard of Care | Total |
|---|---|---|---|---|
| Participants analysed | 58 | 53 | 111 | |
| Age, Customized: Age at enrollment | years | 52.03 (SD 14.43) | 53.79 (SD 15.88) | 52.87 (SD 15.10) |
| Sex: Female, Male: Female | Participants | 44 | 37 | 81 |
| Sex: Female, Male: Male | Participants | 14 | 16 | 30 |
| Race and Ethnicity Not Collected | Participants | — | — | 0 |
| Region of Enrollment: United States | Participants | 12 | 12 | 24 |
| Region of Enrollment: United Kingdom | Participants | 21 | 19 | 40 |
| Region of Enrollment: Spain | Participants | 25 | 22 | 47 |
| BMI | kg/m^2 | 27.37 (SD 5.06) | 29.23 (SD 6.74) | 28.26 (SD 5.97) |
6. Primary Endpoint
The registry lists the primary outcome as Assessment of Post-operative Oedema Formation Using the Figure-of-eight Tape Measurement, measured over Baseline, Day 14 post-op, Day 42 post-op, Day 90 post-op.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Error |
| Unit | cm |
| Endpoint classification | Continuous Endpoint |
The primary endpoint was post-operative oedema assessed with the figure-of-eight tape measurement. This method uses a tape measure along a defined path around the foot and ankle; the resulting circumference-based measure is expressed in cm. It is intended to quantify swelling in a way that can be repeated across visits. The registry describes the primary measure as a mean, with standard error as its dispersion measure.
The scheduled assessments were baseline, Day 14 post-op, Day 42 post-op, and Day 90 post-op. Repeated measurements can describe how the measured swelling changes over follow-up, as well as how the groups compare at an assessment or across time. The registry description states that the endpoint was intended to assess the effect of geko™ therapy on oedema after foot and/or ankle surgery.
The record does not report the actual mean measurements, standard errors, between-group contrasts, confidence intervals, or p-values. It also does not specify in the available endpoint description which particular contrast or time-point comparison was designated for the primary statistical test. Consequently, the endpoint definition can be understood, but the magnitude, direction, and precision of the primary result are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The clinical question is framed as a randomized comparison of standard care plus geko™ therapy against standard care after foot and ankle surgery. The primary measure is a continuous assessment of oedema, recorded in cm using a figure-of-eight tape measurement. The planned follow-up includes baseline and post-operative assessments through Day 90.
The numerical primary-outcome results are not reported in the registry record. In particular, there are no group means, standard errors, estimated contrasts, confidence intervals, or p-values in the available record. Without these statistics, it is not possible to determine from the record whether the measured oedema differed between groups, how large any estimated difference was, or how compatible the results were with a range of possible effects. The absence of these numbers should not be interpreted as evidence that the groups were the same, or that one strategy was better.
The analysis population is also important to interpretation. For the primary outcome, the record describes a modified intention-to-treat population restricted to randomized subjects who attended both baseline and the Day 14 visit. Randomized subjects who missed either visit were excluded from that analysis. This restriction means the primary analysis did not include every randomized subject as described under a strict intention-to-treat approach. The number excluded, reasons for missing visits, and possible differences between included and excluded subjects are not reported in the registry record.
Open-label treatment assignment can affect behavior, care decisions, and reporting of subjective outcomes. The primary endpoint is a tape measurement rather than a self-reported rating, but the record does not say whether the person taking the measurement was masked to assignment or whether measurement procedures were standardized across sites. It is therefore not possible to judge from the record how much these factors could have influenced measurement.
The safety information records serious adverse events in both groups and also lists other adverse events. These counts are descriptive registry figures; they do not establish that an event was caused by the device or that group differences are statistically reliable. The record does not give enough detail to evaluate event timing, severity distribution, or adjustment for differences in time at risk.
Overall, the registry record identifies a clinically relevant randomized comparison and an objective measurement approach, but does not report the primary numerical results needed for an efficacy interpretation. The appropriate conclusion is limited to what was registered: the trial planned and conducted a comparison with the specified endpoint and follow-up, while the primary effect estimate and its precision are not reported in the registry record.
9. Statistical Methods Explained
Statistical methods determine how an outcome is summarized, how groups are compared, and how uncertainty is represented. The registry identifies the primary outcome as a continuous measure summarized by a mean, with standard error as the stated dispersion measure. It does not report the statistical model or test used for the primary comparison. The following points explain the methods concepts relevant to interpreting this kind of trial in general, while distinguishing them from what the registry actually states.
What does a mean describe?
For a continuous endpoint such as a tape measurement in cm, a mean is a summary of the observed measurements in a group. It gives a central value but does not describe the full spread or shape of the measurements. A mean can be influenced by unusually high or low observations. The registry specifies mean as the parameter for the primary endpoint, but does not report the group means at the scheduled assessments.
What does a standard error describe?
In general, a standard error describes the precision of an estimated statistic, such as a sample mean. It is not the same as the variability among individual measurements. A standard error is often used in constructing a confidence interval or conducting a statistical test. The registry specifies standard error as the dispersion measure, but the numerical standard errors are not reported in the registry record. Without them, a reader cannot assess the precision of group means from the record.
What would a between-group estimate mean?
In general, a between-group contrast expresses how far apart the groups are on the outcome under a defined comparison. It can be reported at a particular visit or as a summary across visits, depending on the analysis plan. Interpretation requires knowing what contrast was estimated, how it was calculated, and its uncertainty. The registry gives several planned assessment times but does not report the primary contrast, model, or numerical estimate. No difference should be calculated from the record in the absence of the underlying group summaries.
How should uncertainty be read?
In general, a confidence interval describes a range of estimates that are reasonably compatible with the observed data under the statistical model and its assumptions. A narrow interval indicates greater precision than a wide interval, but an interval alone does not establish clinical importance. A p-value addresses compatibility with a specified null hypothesis under a test's assumptions; it does not measure the size or clinical value of an effect. Neither confidence intervals nor p-values for the primary endpoint are reported in the registry record. Thus, neither statistical precision nor evidence against a null hypothesis can be assessed from the record.
Why can repeated measurements matter?
Measurements at baseline and multiple follow-up visits are related because they come from the same participants. General statistical methods for repeated measurements account for that within-person relationship rather than treating every observation as independent. Different approaches can target different questions: a comparison at a particular visit, a change from baseline, or an overall pattern across follow-up. These approaches need not yield identical estimates. The registry lists the assessment schedule but does not state which repeated-measures method or primary contrast was used.
What is over-dispersion?
Over-dispersion is a general concern for count outcomes when observed variability exceeds what a basic model assumes. It can lead to uncertainty being understated if the analysis does not account for the extra variability. The primary endpoint in this trial is a continuous tape measurement, not a count, so over-dispersion is not the central issue for that endpoint. It could be relevant to some event-count analyses in general, but the registry does not describe such models for the secondary outcomes.
What can planning calculations tell a reader?
In general, sample-size planning calculations illustrate how a study's size might relate to a specified effect, significance level, allocation, and statistical assumptions. The planning illustrations associated with this record are described as based on the observed effect, a two-sided significance level of 0.05, equal allocation, and a normal approximation. They are not the trial's original design justification and should not be described as observed power. The registry record does not report the trial's own sample-size justification. Planning illustrations do not replace the observed effect estimate or its uncertainty, and they cannot supply the missing primary results.
For time-to-event planning, a Schoenfeld calculation concerns the total number of events; other planning calculations are expressed as participants per arm. These are general distinctions in how such planning figures are presented. The primary endpoint is a continuous measurement, and its reported results are absent from the registry record. Any planning number should therefore be kept separate from evidence about the treatment comparison actually observed.
10. Multiplicity, Missing Data and Analysis Populations
The primary measurement was scheduled at baseline, Day 14, Day 42, and Day 90. Assessing an outcome repeatedly raises a general multiplicity question: if multiple time-point comparisons are tested, the chance of at least one apparently unusual result can increase unless the analysis plan accounts for the number and structure of comparisons. A prespecified primary contrast, a repeated-measures model, or an adjustment for multiple testing can address different parts of this issue. The registry record does not report the primary contrast, the testing hierarchy, or any multiplicity adjustment. It is therefore not possible to determine how the statistical significance of multiple outcome comparisons was handled.
The record lists 10 outcome measures and four analyses. It includes the oedema measurement as primary and lists several secondary outcome areas, including adverse events, pain, wound healing, analgesia, and patient-reported outcomes. The registry record does not state which secondary outcomes were confirmatory, how they were ordered, or whether their analyses were adjusted for multiplicity. Secondary findings, if reported elsewhere, would need to be interpreted in light of those unreported details.
Missing data are relevant because the primary analysis excluded randomized subjects who did not attend both baseline and the Day 14 visit. This is the registry's stated modified intention-to-treat definition. The number of subjects excluded, reasons for missed visits, later missing measurements, and any imputation or sensitivity analyses are not reported in the registry record. A complete-visit restriction may yield a group composition different from the full randomized population if attendance is related to prognosis, treatment, or outcome. Whether that occurred cannot be determined from the record.
The record does not report whether all randomized participants were analyzed according to assigned group for secondary outcomes, how protocol deviations were handled, or whether any per-protocol analysis was used. These omissions limit assessment of the analysis population and robustness of the findings.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Standard of Care + Geko™ Therapy | 2 | 58 | 3.4% |
| Standard of Care | 2 | 53 | 3.8% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Standard of Care + Geko™ Therapy | 0 of 58 |
| Standard of Care | 0 of 53 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Standard of Care + Geko™ Therapy | 23 of 58 |
| Standard of Care | 10 of 53 |
Most frequent serious adverse event terms
| Event term | Organ system | Standard of Care + Geko™ Therapy | Standard of Care |
|---|---|---|---|
| Surgical wound complications | Injury, poisoning and procedural complications | 1 of 58 | 1 of 53 |
| Nerve pain in operated foot | General disorders | 2 of 58 | 0 of 53 |
| Potential peripheral nerve damage in operated foot | Injury, poisoning and procedural complications | 0 of 58 | 1 of 53 |
| Opioid induced nausea | Gastrointestinal disorders | 1 of 58 | 0 of 53 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Standard of Care + Geko™ Therapy | Standard of Care |
|---|---|---|---|
| Post-operative pain and/or swelling | Injury, poisoning and procedural complications | 6 of 58 | 6 of 53 |
| Rash or irritation at device application site | Skin and subcutaneous tissue disorders | 9 of 58 | 0 of 53 |
| Surgical wound complications | Injury, poisoning and procedural complications | 3 of 58 | 2 of 53 |
| Parasthesia in operated foot | General disorders | 2 of 58 | 1 of 53 |
| Fall | Injury, poisoning and procedural complications | 3 of 58 | 0 of 53 |
| Rash on operated foot | Skin and subcutaneous tissue disorders | 1 of 58 | 0 of 53 |
| Urinary tract infection | Infections and infestations | 0 of 58 | 1 of 53 |
| Bruising on operated foot | Injury, poisoning and procedural complications | 0 of 58 | 1 of 53 |
| Opioid induced nausea | Gastrointestinal disorders | 1 of 58 | 0 of 53 |
| Loosened backslab cast | General disorders | 1 of 58 | 0 of 53 |
Serious events with the highest arm-level rate: nerve pain in operated foot (3.4%), surgical wound complications (1.9%), potential peripheral nerve damage in operated foot (1.9%), opioid induced nausea (1.7%).
The registry records serious adverse events for the two treatment groups. In the standard care plus geko™ therapy group, 2 affected participants were recorded among 58 at risk. In the standard care group, 2 affected participants were recorded among 53 at risk. No deaths were recorded in either group. These are descriptive counts in the registry record; they do not by themselves show whether an event was caused by treatment, or whether the groups differ reliably.
Other adverse events were recorded for 23 among 58 at risk in the standard care plus geko™ therapy group, and 10 among 53 at risk in the standard care group. The registry record does not provide event-level timing, severity breakdown, duration, or a statistical comparison for these figures. It also does not report whether people could contribute more than one event or how repeated events were handled, so counts should not be treated as a detailed account of event frequency.
The record lists serious-event terms with percentages: Nerve pain in operated foot, 3.4%; Surgical wound complications, 1.9%; Potential peripheral nerve damage in operated foot, 1.9%; and Opioid induced nausea, 1.7%. The denominator and method behind these term-specific percentages are not reported in the registry record. These listed terms should therefore be read as registry-reported safety descriptions, not as evidence that the device caused the events or as directly comparable group-specific risks.
12. What the Result Does, and Does Not, Mean
The trial addresses a specific statistical and clinical question: whether post-operative oedema measurements differ between patients assigned to standard care and patients assigned to standard care plus geko™ therapy. Randomization provides a design intended to make the groups comparable at assignment, while the planned tape measurement offers a quantitative outcome. The registry also specifies follow-up through Day 90 post-op and a modified intention-to-treat analysis population for the primary endpoint.
Those design features do not substitute for the numerical results. The registry record does not report group means, standard errors, the estimated between-group difference, confidence intervals, or p-values for the primary outcome. It is therefore not possible to infer the size, direction, or precision of an effect. A missing result is not evidence of no effect, and an endpoint description is not evidence that a difference was observed.
Nor can a reader determine the clinical importance of a potential measurement difference from the record. That judgment would require a clearly defined contrast, its uncertainty, and context for interpreting the amount of change in the measured circumference. The registry does not report a threshold for a clinically important difference. No such threshold can be inferred from the endpoint name alone.
The trial's open-label design, incomplete description of the post-discharge treatment schedule, and modified intention-to-treat population are relevant when considering how the study was conducted and analyzed. They do not establish bias, but they identify questions that cannot be resolved without additional methods and results information. In particular, the record does not explain whether measurement assessors were masked or how missing follow-up was addressed.
The safety counts provide a descriptive record of serious and other adverse events, but they cannot establish causation or a comparative safety profile on their own. The event-term percentages also lack a reported denominator in the registry record. Overall, the information supports describing the trial's design, intended endpoint, and recorded safety summaries. It does not support a conclusion that geko™ therapy is effective, ineffective, safer, or less safe.
13. Why This Trial Matters Statistically
This trial is statistically notable for combining a randomized parallel-group design with a continuous, measurement-based post-operative endpoint. A tape measurement can be summarized using means and compared quantitatively, which can make the estimand more concrete than a broad clinical label such as swelling. The scheduled assessments also recognize that post-operative oedema is followed over time rather than represented by a single observation.
At the same time, repeated measurement creates analytic choices. A group comparison at Day 14 asks a different question from a comparison of change from baseline or a model of the full follow-up pattern. These choices affect the interpretation of an estimated effect and the way uncertainty is calculated. The registry record identifies the measurement schedule but does not report the primary contrast or statistical model, leaving an important part of the analysis question unresolved.
The modified intention-to-treat definition is another important issue. Requiring attendance at baseline and Day 14 may exclude randomized participants from the primary analysis. Statistical interpretation depends not only on the endpoint but also on who contributes data and how missing observations are handled. The record does not report exclusion counts, missing-data methods, or sensitivity analyses, limiting the assessment of whether the result would be robust to alternative assumptions.
Finally, the distinction between a registered design and an available result is essential. Enrollment, follow-up dates, outcome definitions, and safety counts describe aspects of the trial, but they are not substitutes for the primary estimate and its uncertainty. The absence of those numerical results makes it impossible to judge the precision or direction of the main comparison from the registry record. This is a useful reminder that a clear endpoint and randomized design are only part of the evidence needed for statistical interpretation.
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.
The main trial-specific limitation of the registry record for interpreting the primary outcome is that it does not report numerical results. Group means, standard errors, between-group estimates, confidence intervals, and p-values are not reported in the registry record. Without those figures, neither effect magnitude nor precision can be assessed.
The primary analysis population is restricted to randomized subjects who attended both baseline and Day 14. The record does not state how many participants were excluded for missing either visit or why they did not attend. It does not report how missing measurements at later visits were handled, whether imputation was used, or whether sensitivity analyses examined alternative assumptions. This leaves uncertainty about the effect of incomplete follow-up on the analysis.
The registry describes an open-label trial, but does not report whether the staff measuring oedema were masked to treatment assignment. It also does not give details of measurement training, repeatability, or procedures for standardizing tape placement across centers. Such details matter when an endpoint depends on a measurement procedure.
The treatment description is incomplete after the period of inpatient use. The record states that therapy was applied immediately post-surgery and used 24 hours / day while the patient remained in hospital, but does not fully specify the later schedule. The standard-care arm is described according to hospital practice, without a detailed common protocol. The record also does not explain allocation concealment, the randomization method, or the statistical model for repeated measures. These are limitations of what can be established from the registry record, not proof that trial procedures were inadequate.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Foot and Ankle Post-operative Oedema Management Using Geko™ — NCT04927234.
- Registry record last updated 2026-10-07; status last verified 2026-09.
- Results first posted 2026-10-07.
- 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.
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18. Record Summary
The registry describes a completed, multicentre, randomized, open-label, parallel-group trial of standard care versus standard care plus geko™ therapy after foot and/or ankle surgery. Enrollment was 123. The primary endpoint was mean figure-of-eight tape measurement in cm, with standard error specified as the dispersion measure. Assessments were scheduled at baseline and Day 14, Day 42, and Day 90 post-op.
The primary analysis used a modified intention-to-treat population limited to randomized subjects who attended both baseline and Day 14; those who did not complete both visits were excluded. Numerical primary-outcome results and the primary statistical comparison are not reported in the registry record. Serious and other adverse-event counts are recorded by group, and several serious-event terms are listed with percentages. The record does not report enough detail to establish event causality or interpret the primary treatment effect.