- Garden classifies intracapsular femoral neck fractures by the degree of displacement on the anteroposterior radiograph and guides urgency of reduction, fixation method and counselling on complication risk.
- Type I is valgus-impacted or incomplete; Type II is complete but undisplaced; Type III shows partial displacement; Type IV is fully displaced with no cortical contact.
- Undisplaced fractures (I and II) are usually fixed with cannulated screws or a sliding hip screw; displaced fractures (III and IV) in younger patients need urgent open or closed reduction and internal fixation, while older patients often receive arthroplasty.
- Displacement increases the risk of avascular necrosis and nonunion because the retinacular vessels are stretched or torn; the risk rises sharply once the fracture is displaced.
The Garden system is the standard language for intracapsular neck of femur fractures, but inter-observer reliability is only moderate for the four-type version. In practice and in most exam answers, fractures are dichotomised into undisplaced (Garden I-II) versus displaced (Garden III-IV) because this binary split drives treatment and has better reproducibility. Always state both the full Garden type and the clinical dichotomy when describing a fracture.
The Garden Classification System

The Garden classification is based on the appearance of the femoral head and neck on the anteroposterior radiograph. It describes the position of the capital fragment relative to the acetabulum and the degree of cortical continuity.
| Type | Description | Key Radiographic Signs | Displacement Status |
|---|---|---|---|
| I | Valgus-impacted or incomplete | Head tilted into valgus on neck; trabeculae still aligned or slightly impacted; cortical break incomplete | Undisplaced |
| II | Complete but undisplaced | Full fracture line visible across neck; head and neck remain aligned; no varus or valgus tilt | Undisplaced |
| III | Partially displaced | Head tilted into varus; partial cortical contact remains; fracture line oblique | Displaced |
| IV | Fully displaced | No cortical contact; head free in acetabulum or rotated; shaft displaced proximally and externally rotated | Displaced |
Incomplete β’ Complete β’ Partial β’ FreeGarden I to IV progression
The critical distinction is between undisplaced (I-II) and displaced (III-IV). Undisplaced fractures preserve the retinacular blood supply far better; once displacement occurs the superior retinacular vessels are at risk and avascular necrosis becomes a real threat.
Garden Types and Management Implications
Management decisions are driven by patient age, comorbidities, fracture displacement and the viability of the femoral head.
| Garden Type | Patient Group | Preferred Treatment | Key Considerations |
|---|---|---|---|
| I or II (undisplaced) | Any age | Internal fixation β cannulated screws or sliding hip screw | Preserve the head; low AVN risk; allow early mobilisation |
| III or IV (displaced) | Young, fit (< 60-65 years) | Urgent closed or open reduction and internal fixation | Within 6-12 hours ideally; aim for anatomical reduction; higher AVN risk |
| III or IV (displaced) | Older, frail (> 75-80 years) | Cemented hemiarthroplasty or total hip arthroplasty | Avoid prolonged surgery; allow immediate full weight-bearing; lower re-operation rate than fixation |
In a young patient with a displaced Garden III or IV fracture, time is critical. Every hour of delay increases the risk of avascular necrosis. Reduce anatomically, compress the fracture, and protect the reduction with a sliding hip screw or cannulated screws placed in an inverted-triangle configuration.
Undisplaced fix β’ Displaced young reduce β’ Displaced old replaceTreatment by displacement
Limitations and Reliability
- The four-type Garden system has only moderate inter-observer reliability; many surgeons cannot consistently distinguish Type II from Type III on plain radiographs.
- The binary split into undisplaced versus displaced is far more reproducible and is what most guidelines and registries actually use for outcome reporting.
- Garden does not account for posterior comminution, which is visible on the lateral radiograph and increases the risk of fixation failure.
- The classification is purely radiographic and does not incorporate patient factors such as bone quality, comorbidities or time to presentation.
- Modern CT and MRI can detect occult Garden I fractures and assess femoral head perfusion, but the Garden label itself remains a plain-film tool.
Evidence Base
Garden classification of femoral neck fractures: inter-observer reliability
- Moderate kappa values for the four-type Garden classification among orthopaedic surgeons
- Agreement improved substantially when fractures were grouped as undisplaced versus displaced
- Posterior comminution on the lateral view was an important but under-recognised prognostic factor
Internal fixation versus arthroplasty for displaced femoral neck fractures in the elderly
- Meta-analysis showed lower re-operation rate with arthroplasty than with internal fixation for displaced fractures in older patients
- Functional outcomes similar at two years but arthroplasty avoided the complications of nonunion and AVN
- Cemented hemiarthroplasty offered the best balance of low re-operation and acceptable morbidity
Does Garden type I incomplete femoral neck fracture really exist in older adults? To evaluate the stability and consistency of Garden classification.
- Garden classification shows only moderate inter-observer reliability even among experienced surgeons
- Many apparent Garden I fractures are complete on CT, questioning the existence of truly incomplete fractures in osteoporotic bone
- Simplifying to undisplaced versus displaced improves both reliability and clinical utility
Femoral neck fracture: the reliability of radiologic classifications.
- Garden classification demonstrated only fair to moderate inter-observer agreement (kappa approximately 0.4-0.6)
- The undisplaced versus displaced dichotomy showed better reproducibility than the four individual Garden types
- Similar limitations in reliability were observed with the AO/OTA classification
Exam Viva
Practise clinical reasoning and management decisions out loud
βA 68-year-old woman falls at home and sustains a left femoral neck fracture. The anteroposterior radiograph shows a complete fracture line with the head tilted into slight varus and partial cortical contact. What is the Garden classification and how would you manage her?β
βA 52-year-old man is brought in after a high-energy road-traffic collision. He has a displaced femoral neck fracture that you classify as Garden IV. Outline your operative plan and the key discussion points for consent.β
The four Garden types
- Type I: valgus-impacted or incomplete β head tilted into valgus, trabeculae aligned
- Type II: complete but undisplaced β full fracture line visible, head and neck aligned
- Type III: partially displaced β varus tilt, some cortical contact remains
- Type IV: fully displaced β no cortical contact, head free or rotated
Clinical dichotomy that actually matters
- Undisplaced (Garden I-II): fix with screws or sliding hip screw in almost all patients
- Displaced (Garden III-IV): young patient β urgent reduction and fixation; older patient β arthroplasty
- Displacement increases AVN risk from under 10 percent to 20-30 percent
- Always obtain and review the lateral radiograph for posterior comminution
Key exam points and pitfalls
- Reliability is moderate for four types; excellent for the binary undisplaced versus displaced split
- Garden does not replace clinical judgement β bone quality, comorbidities and time since injury all matter
- In young patients with displaced fractures, document the time of injury and aim for theatre within 6-12 hours
- Posterior comminution on the lateral view predicts loss of reduction even if the anteroposterior view looks acceptable