Landmark Orthopaedic Trials
Know the question | know the population | know the limit
Landmark Trial Families
Critical Must-Knows
- A landmark trial is not an automatic rule. It is a strong decision anchor only when the patient, intervention, comparator and outcome match the case.
- Surgical trials often have crossover and incomplete blinding. Interpret intention-to-treat and as-treated results carefully.
- The primary outcome matters. A trial powered for function may not answer rare complications, implant survival or subgroup effects.
- Negative does not mean useless. Many trials show that routine surgery adds little for broad low-risk groups but may still help selected patients.
- Trial literacy changes management discussions. It improves consent, shared decision-making and avoidance of low-value surgery.
Clinical Pearls
- "Open every trial discussion with the PICO and the primary outcome.
- "State what the trial changed and what it did not answer.
- "Be careful applying pragmatic trial results to excluded high-risk subgroups.
- "In fracture trials, distinguish radiographic success from patient-centred function and reoperation.
- "In arthroplasty prophylaxis trials, separate symptomatic VTE, bleeding, mortality and protocol context.
Do not quote a trial without stating the patient group
“PROFHER showed no difference” or “DRAFFT changed distal radius fixation” is incomplete. A useful answer states the population, comparator, outcome and limitation. The wrong extrapolation is often more dangerous than not knowing the acronym.

How to Use a Trial
PICOQuestion | SAFEValidity | CASTClinical use |
|---|---|---|
P Patient Age, injury, severity, setting and exclusions. | S Selection Who was included and excluded? | C Context Does the trial setting match yours? |
I Intervention Operation, implant, pathway or medication. | A Allocation Was randomisation protected? | A Absolute effect What is the real size of benefit or harm? |
C Comparator Non-operative care, another operation or placebo. | F Follow-up Was outcome capture complete? | S Subgroups Was this subgroup powered or exploratory? |
O Outcome Function, reoperation, complications, mortality or cost. | E Endpoint Was the primary outcome clinically meaningful? | T Tradeoff What are the risks, costs and downstream procedures? |
No PICO, no application. | A famous trial can still have limits. | Cast evidence onto the actual patient. |
No PICO, no application.
A famous trial can still have limits.
Cast evidence onto the actual patient.
Overview
Landmark trials are studies that changed, challenged or clarified common orthopaedic decisions. They are most useful when they are remembered as clinical questions rather than as acronyms.
A good landmark-trial discussion should answer:
- What patient population was studied?
- What was the intervention and comparator?
- What primary outcome was used?
- What was the practice signal?
- What are the limitations and excluded patients?
- How should the result affect consent and management?
The complete one-sentence trial answer
“This trial asked whether intervention X compared with Y improved outcome Z in patient group P; the main signal was this, but I would not apply it automatically to these excluded or higher-risk patients.”
Concepts and Core Principles


What Makes a Trial Practice-Changing?
| Domain | Question | Why It Matters |
|---|---|---|
| Clinical relevance | Does the trial answer a decision surgeons face often? | Common decisions such as distal radius fixation or proximal humerus surgery affect many patients. |
| Internal validity | Were randomisation, allocation, follow-up and outcome assessment credible? | A flawed trial can mislead even if large. |
| Effect size | Is the difference clinically meaningful, not just statistically significant? | Small differences may not justify operative risk. |
| Applicability | Do the inclusion criteria match the patient in front of you? | A trial may exclude severe displacement, open injury, frailty or revision cases. |
| Downstream consequences | Did the trial capture reoperation, complications, cost and later crossover? | Orthopaedic decisions often have delayed consequences. |
Classification of Landmark Trials
Trial Style
| Style | Strength | Limitation |
|---|---|---|
| Explanatory trial | Tests whether an intervention can work under controlled conditions. | May not represent everyday surgical practice. |
| Pragmatic trial | Tests whether a strategy works in real clinical settings. | Treatment heterogeneity and crossover can dilute the result. |
Trauma Trials
Trauma Trial Signals
| Trial | Clinical Question | Practice Signal |
|---|---|---|
| DRAFFT | For adult dorsally displaced distal radius fractures, how do K-wires and volar locking plates compare? | Plate fixation was challenged as routine treatment for broad displaced distal radius fracture groups; cost, reoperation and patient selection matter. |
| DRAFFT 2 | After manipulation of dorsally displaced distal radius fractures, is K-wire fixation better than moulded cast? | Moulded cast was a serious comparator after acceptable reduction; avoid automatic fixation when stability and patient factors permit casting. |
| PROFHER | For displaced proximal humerus fractures in adults, does surgery improve patient-reported outcomes over non-operative care? | Routine surgery for many displaced proximal humerus fractures was strongly challenged; selected fracture patterns and younger/high-demand patients still need individual assessment. |
| FLOW | In open fractures, what irrigation pressure and solution should be used? | Very high pressure lavage did not become the default; soap solution raised concern. Normal saline and sensible pressure remain common practice anchors. |
| FAITH | For femoral neck fracture fixation, do sliding hip screws and cancellous screws differ? | Implant choice must be matched to fracture biology, displacement and patient factors; fixation failure remains central. |
| HEALTH | For displaced femoral neck fracture in independently ambulatory older adults, THA or hemiarthroplasty? | THA gave modest functional advantages in selected patients but with tradeoffs including dislocation; selection is key. |
| FORCE | For paediatric distal radius torus fractures, bandage or rigid immobilisation? | Simple bandage and discharge strategy is reasonable for uncomplicated torus fractures, reducing overtreatment. |
Trauma trial limitation
Fracture trials usually answer a strategy question for a defined injury group. They do not remove the need to assess displacement, soft tissue, bone quality, open injury, neurovascular status, patient demand and ability to comply with follow-up.
Sports and Knee Trials
Sports and Knee Trial Signals
| Trial | Clinical Question | Practice Signal |
|---|---|---|
| KANON | Early ACL reconstruction versus structured rehabilitation with optional delayed reconstruction. | Not every ACL rupture requires immediate reconstruction; instability episodes, goals, pivoting sport and meniscal risk guide individual decisions. |
| METEOR | Arthroscopic partial meniscectomy versus physical therapy in meniscal tear with osteoarthritis. | Physical therapy is a strong first-line option for many degenerative meniscal tears with OA; crossover matters. |
| FIDELITY | Arthroscopic partial meniscectomy versus sham surgery for degenerative meniscal tear. | Routine arthroscopic partial meniscectomy for degenerative meniscal symptoms without clear mechanical indication was strongly challenged. |
| MOON | Prospective ACL cohort evidence on outcomes, graft choice and predictors. | Useful for prognosis and counselling, but not a single randomised treatment rule. |
Degenerative meniscus discussion
The central counselling point is not “arthroscopy never works.” It is that high-quality evidence has narrowed the indication: degenerative meniscal symptoms with osteoarthritis usually need education, rehabilitation and non-operative care before considering arthroscopy, unless there is a specific mechanical problem or atypical scenario.
Arthroplasty Trials
Arthroplasty Trial Signals
| Trial | Clinical Question | Practice Signal |
|---|---|---|
| CRISTAL | Aspirin versus enoxaparin for symptomatic VTE prevention after hip or knee arthroplasty. | Enoxaparin performed better for symptomatic VTE in the trial context; prophylaxis choice must account for local protocol, bleeding risk and patient risk. |
| EPCAT II | After initial rivaroxaban, can aspirin continue extended prophylaxis after hip or knee arthroplasty? | Aspirin can be part of selected sequential prophylaxis pathways; do not confuse this with aspirin-only from day zero for all patients. |
| Registry signals | Which implants, bearings or fixation strategies survive in real-world use? | Registry findings are powerful for implant surveillance but remain observational and confounded. |
Spine Trials
Spine Trial Signals
| Trial | Clinical Question | Practice Signal |
|---|---|---|
| SPORT disc herniation | Surgery versus non-operative care for lumbar disc herniation. | Surgery can provide faster symptom relief for selected patients; long-term interpretation is affected by crossover. |
| SPORT spinal stenosis | Decompression strategy versus non-operative care for symptomatic lumbar stenosis. | Supports benefit of surgery in selected symptomatic stenosis, but patient selection and expectations matter. |
| SPORT degenerative spondylolisthesis | Surgery versus non-operative care for degenerative spondylolisthesis with stenosis. | Supports surgery for selected symptomatic patients, but treatment choice depends on instability, deformity and patient risk. |
Spine trial interpretation
Spine trials are highly affected by crossover, symptom severity, imaging-symptom correlation and patient preference. Quote the signal, then explain how patient selection changes the decision.
Clinical Relevance and Application

How to State a Landmark Trial in Practice
| Step | Good Answer | Weak Answer |
|---|---|---|
| Name the question | PROFHER studied surgery versus non-operative care for displaced proximal humerus fractures in adults. | PROFHER says no surgery. |
| Name the outcome | The key outcome was patient-reported function, not perfect radiographic anatomy. | The X-ray looks better after surgery. |
| Name the limitation | I would still individualise younger patients, fracture-dislocations, head-splitting injuries and clear surgical indications. | The trial applies to every proximal humerus fracture. |
| Translate to management | This evidence supports shared decision-making and avoids routine surgery in broad low-risk groups. | I quote the acronym and stop. |
Evidence Base
DRAFFT distal radius fixation
- DRAFFT compared K-wires with volar locking plates in adult dorsally displaced distal radius fractures.
- DRAFFT 2 compared moulded cast with K-wire fixation after manipulation.
- Together they discourage automatic escalation to expensive or invasive fixation for broad fracture groups.
PROFHER proximal humerus
- Surgery did not show a clear patient-reported outcome advantage over non-operative treatment in the studied displaced proximal humerus fracture population.
- The trial strongly challenged routine fixation for broad adult displaced proximal humerus fracture groups.
- Interpretation depends on fracture pattern, patient age and exclusions.
FLOW open fracture irrigation
- FLOW tested irrigation pressure and solution strategy in open fracture wounds.
- It shifted open-fracture irrigation discussion from tradition toward evidence.
- Soap solution became less attractive after trial signals.
HEALTH femoral neck fracture
- Compared THA with hemiarthroplasty for displaced femoral neck fracture in selected ambulatory older adults.
- THA offered modest functional benefits but with important tradeoffs.
- Patient selection remains central.
Clinical Scenarios
Use these scenarios to practise clinical reasoning and management decisions
Applying PROFHER
"An older adult presents with a displaced proximal humerus fracture. The radiograph is shown and the examiner asks whether PROFHER means surgery should never be offered."
Degenerative meniscal tear
"A patient with degenerative meniscal symptoms and osteoarthritis asks whether arthroscopy will fix the problem."
Arthroplasty prophylaxis
"A colleague says EPCAT II and CRISTAL prove aspirin is either always safe or never safe after arthroplasty."
Landmark Trials: Key Takeaways
Clinical summary
How to quote
- •State patient group.
- •State intervention and comparator.
- •State primary outcome.
- •State practice signal and limitation.
Trauma
- •DRAFFT: distal radius fixation choices.
- •PROFHER: proximal humerus surgery challenged.
- •FLOW: open fracture irrigation evidence.
- •HEALTH: THA versus hemiarthroplasty tradeoffs.
- •FORCE: simple care for torus fracture.
Sports/Knee
- •KANON: ACL rehab-first strategy for selected patients.
- •METEOR: physical therapy strong for meniscus with OA.
- •FIDELITY: degenerative meniscectomy challenged by sham trial.
- •MOON: ACL cohort for prognosis and counselling.
Arthroplasty/Spine
- •CRISTAL and EPCAT II answer different prophylaxis questions.
- •SPORT supports selected spine surgery but crossover matters.
- •Registry signals are useful but observational.
Common errors
- •Overgeneralising.
- •Ignoring exclusions.
- •Forgetting the primary outcome.
- •Treating non-inferiority like superiority.
- •Using a trial as an automatic rule.