MS Ortho Theory Exam Guide - KNRUHS (Manish Kumar Varshney)

About the Book

• 2 Essays x 20 marks = 40
• 6 Short Notes x 10 marks = 60
• Total = 100 per paper

Where to Start - Priority Order

PHASE 1: Basic Sciences Foundation (Paper I / Part I)

PHASE 2: Core Traumatology Topics (Paper - Traumatology)

1. Fracture Neck of Femur - Classify + management in elderly (Garden's classification, hemiarthroplasty vs THA vs DHS)
2. Fracture Distal Radius - Classification (Frykman, AO), management, recent advances
3. Talus fractures - Hawkins classification, AVN risk, management
4. ACL injuries - Anatomy of knee, investigations, reconstruction techniques
5. Tibial plateau fractures - Schatzker classification, management
6. Fracture Shaft Femur - Management, complications, IMN technique
7. Calcaneum fractures - Essex-Lopresti, management
8. Open fractures - Gustilo-Anderson, Byrd classification, management principles
9. Compartment syndrome - Pathophysiology, diagnosis, fasciotomy
10. Fat embolism syndrome - Gurd's criteria, management

• Monteggia fracture dislocation (Bado classification)
• Galeazzi fracture
• Colles fracture vs Smith's fracture
• Bohler's angle
• Talar neck fractures - Hawkins sign
• Principles of external fixation
• SIGN nail / Interlocking nail mechanics

PHASE 3: Core Orthopaedics Topics (Paper - Orthopaedics)

1. TB of Hip - Classification, clinical features, investigations, management (Ironside classification, Oswestry staging)
2. TB of Spine (Pott's disease) - Clinical features, complications (Pott's paraplegia - Seddon), management, surgery indications
3. Osteosarcoma - Classification, staging (Enneking), clinical features, management
4. Osteoarthritis of Knee - Pathology, classification, management (TKA)
5. Congenital Talipes Equinovarus (CTEV/Clubfoot) - Ponseti method in detail
6. Developmental Dysplasia of Hip (DDH) - Diagnosis, Ortolani/Barlow, management
7. Legg-Calve-Perthes Disease - Herring classification, management
8. Rheumatoid Arthritis - Joint involvement, medical management, surgical options
9. Cervical spondylosis - Clinical features, management, indications for surgery
10. Intervertebral disc prolapse (PIVD/PLID) - Pathology, clinical features, management

• Ewing's sarcoma vs Osteosarcoma
• Kocher's method (shoulder reduction)
• Thomas test / FABER test
• Scoliosis - Cobb angle measurement
• Spinal stenosis
• Limb length discrepancy assessment
• Bone tumour staging (Enneking system)

PHASE 4: Recent Advances Paper

• Arthroscopy - knee, shoulder principles and indications
• Total Knee/Hip Arthroplasty - fixation types, bearing surfaces, complications
• Ilizarov technique and principles
• Minimally invasive surgery in orthopaedics
• Bone substitutes and tissue engineering
• Navigation and robotic surgery (awareness level)
• Biological therapies - PRP, stem cells in orthopaedics
• Locked plating principles

How to Use Varshney's Book Effectively

1. Chapter-wise theory content - read for concept clarity
2. Chapter 11 (Long Questions for Theory Exams) - practice writing answers
3. Chapter 12 (Short Notes) - revise in last 2 weeks before exam

Library Books Available to You Here

• Miller's Review of Orthopaedics 9th Edition - excellent for MCQ-style facts, classifications, tables. Use for basic sciences and quick revision.
• Campbell's Operative Orthopaedics 15th Edition (2026) - the gold standard reference. Use it to understand surgical techniques asked in essays.
• Rockwood and Green's Fractures in Adults 10th Ed (2025) - best for fracture classification and management.

Quick Tips for KNRUHS Theory

1. Always start essays with a classification - examiners expect it upfront
2. Draw diagrams for fracture patterns, surgical approaches - they fetch marks
3. Mention complications - early and late, always
4. Recent advances paragraph - add 4-5 lines on recent advances at the end of every essay, even in Paper I and II
5. Scoring pattern is generous - structured answers with headings score better than prose

Paper II (Orthopaedic Diseases) - Top 10 Questions, Ranked by Importance

🥇 1. Tuberculosis of Spine (Pott's Disease)

• Pathology: paradiscal, central, anterior, appendageal types
• Pott's paraplegia - Seddon's classification (early onset vs late onset)
• Investigations: X-ray (gibbus), MRI findings, Mantoux, biopsy
• Medical management: HRZE regimen
• Surgical indications + approaches: anterior (transthoracic, retroperitoneal), posterior instrumentation
• Complications: cold abscess, gibbus, kyphosis

🥈 2. TB of Hip Joint

• Stages: synovial → early arthritis → advanced arthritis → fibrous/bony ankylosis
• Wandering acetabulum, pathological dislocation
• Investigations, medical Rx, surgical options (arthrodesis, THR timing)
• Ironside classification

🥉 3. Osteosarcoma

• Enneking staging (IA, IB, IIA, IIB, III)
• Codman's triangle, sunray appearance on X-ray
• Biopsy principles (Mankin's rules)
• Limb salvage surgery vs amputation
• Neoadjuvant chemotherapy: MAP protocol (Methotrexate, Adriamycin, Cisplatin)
• Survival rates, recent advances (mifamurtide)

4. Giant Cell Tumour (GCT)

• Campanacci grading (I, II, III)
• Histology: mononuclear stromal cells + osteoclast-like giant cells
• X-ray: soap bubble, eccentric epiphyseal lesion
• Management: extended curettage + cementation/bone graft vs resection
• Denosumab for unresectable/recurrent GCT
• Recurrence rate ~25%

5. Developmental Dysplasia of Hip (DDH)

• Embryology, risk factors
• Ortolani's test (reduction click), Barlow's test (dislocation click)
• Hilgenreiner's line, Perkin's line, acetabular index, Shenton's line
• Management by age: Pavlik harness (0-6 months), closed reduction + spica (6-18 months), open reduction (>18 months), osteotomies (>2 years)
• Salter's osteotomy, Dega, Pemberton - indications

6. Osteoarthritis of Knee / Total Knee Arthroplasty (TKA)

• Pathology of OA: cartilage loss, subchondral sclerosis, osteophytes
• Kellgren-Lawrence grading
• Conservative management → HTO indications → TKA
• TKA: components (femoral, tibial, patellar), cemented vs cementless, PCL retention vs substitution
• Complications: PE, infection, stiffness, loosening

7. Legg-Calve-Perthes Disease (LCPD)

• Age group 4-8 years, 4:1 male predominance
• Pathology: AVN of femoral head → fragmentation → healing → remodeling
• Catterall classification (I-IV), Herring lateral pillar classification (A/B/B-C/C)
• Stulberg outcome classification
• Management: containment (abduction brace, femoral/pelvic osteotomy)
• Poor prognosis signs: Gage sign, calcification lateral to epiphysis, lateral subluxation, horizontal physis

8. Cervical Spondylosis / Cervical Disc Prolapse

• Pathology: disc degeneration, osteophyte formation, ligamentum flavum hypertrophy
• Clinical features: neck pain, radiculopathy (dermatomal), myelopathy (long tract signs, Lhermitte's sign, Nurick grading)
• Investigations: MRI gold standard, CT for bony detail
• Conservative management
• Surgical: ACDF (anterior cervical discectomy and fusion), posterior laminectomy/laminoplasty - indications
• Nurick grading for myelopathy

9. Rheumatoid Arthritis (Hand / Wrist / Management)

• Pathology: synovitis → pannus → cartilage/bone destruction
• Deformities: ulnar drift, boutonniere, swan-neck, Z-thumb, caput ulnae
• Felty's syndrome, extra-articular features
• ACR diagnostic criteria
• DMARDs: Methotrexate first line, biologics (TNF-alpha inhibitors, rituximab)
• Surgical options: synovectomy, arthroplasty, arthrodesis

10. Osteomyelitis (Acute Haematogenous / Chronic)

• Pathogenesis: metaphyseal predilection, subperiosteal abscess, involucrum, sequestrum, cloacae
• Cierny-Mader classification (chronic OM)
• Organisms: S. aureus most common; Salmonella in sickle cell
• Investigations: X-ray (late), MRI (early - gold standard)
• Management: antibiotics (empirical then culture-guided), surgical debridement, sequestrectomy
• Sickle-cell osteomyelitis - special entity (April 2026 short note)

Bonus Short Notes to Prepare (in case essays are predictable)

• Scoliosis (Cobb angle, classification, management)
• AVN of femoral head - Ficat staging, management
• Ewing's sarcoma (vs Osteosarcoma table)
• Thoracic outlet syndrome
• High Tibial Osteotomy (HTO)
• Limb length discrepancy
• Brachial plexus injury

Part A: PubMed Evidence - TB Spine Surgical Techniques & Outcomes (2022-2026)

Key Finding Summary

What to Write in Your Recent Advances Paragraph (for TB Spine Essay)

• Anterior approach has fewer complications and better kyphosis correction than posterior alone (Arifin et al., Spine Deformity 2024)
• Single posterior approach is gaining ground for lumbar TB - less trauma, equivalent neurological outcomes (Duan et al., Ortho Surg 2023)
• Single-stage combined anterior-posterior surgery gives 89.5% neurological recovery for tuberculous paraplegia (Yadav et al. 2023)

• Titanium mesh cage vs autologous bone graft - no significant difference in fusion rate, VAS, or kyphosis correction (Deng et al., BMC Surg 2023)
• Bone graft still preferred by some due to lower subsidence rates (RR 9.30 for mesh subsidence)

• MRI remains gold standard for early diagnosis
• Tissue PCR (Gene Xpert/Xpert MTB/RIF) is now gold standard for microbiological diagnosis - faster and detects rifampicin resistance
• Epidural/paravertebral abscess with cord involvement seen in 72.9% of cervical TB cases on MRI

• Rising MDR-TB is the biggest challenge to the WHO "End TB Strategy" (Rajasekaran et al. 2023)

Part B: Paper II (Traumatology) - Top 10 Questions in Order of Importance

🥇 1. Fracture Neck of Femur

• Garden's classification (I-IV); AO/OTA classification
• Blood supply of femoral head (Trueta) - ascending cervical branches, retinacular vessels
• Management by age + displacement: young patient (ORIF, DHS, cannulated screws) vs elderly displaced (hemiarthroplasty - Austin Moore/bipolar vs THA)
• Complications: AVN (30-35%), non-union, implant failure
• Recent advance: Femoral Neck System (FNS) - asked as short note April 2026 Paper IV

🥈 2. Tibial Plateau Fractures

• Schatzker classification (I-VI)
• Luo's Three-Column Theory (recent advance) - medial, lateral, posterior columns
• CT scan mandatory for surgical planning
• Management: conservative (undisplaced <3mm), ORIF (buttress plating), arthroscopy-assisted
• Complications: compartment syndrome, stiffness, post-traumatic OA, peroneal nerve injury

🥉 3. Pelvic Ring Fractures

• Young-Burgess classification (LC, APC, VS, CM types)
• Tile's classification (A stable, B rotationally unstable, C both unstable)
• ATLS resuscitation - life before limb
• Management: pelvic binder (first aid), external fixator (damage control), ORIF (definitive)
• Surgical approaches: Pfannenstiel (pubic symphysis), ilioinguinal approach, Kocher-Langenbeck (posterior)
• C-clamp for posterior ring instability

4. Open Fractures

• Gustilo-Anderson classification (Type I, II, IIIa, IIIb, IIIc) - know the criteria by heart
• Byrd and Spicer soft tissue classification
• 6-hour rule (historical) - current evidence: no strict time limit but early surgery preferred
• Management: ABC, wound debridement, fracture stabilisation (ex-fix in III), wound coverage
• Antibiotics: Type I/II = 1st gen cephalosporin; Type III = add gentamicin ± metronidazole
• Wound closure: primary (Type I), delayed primary (Type II), flap (Type IIIb)

5. Fracture Distal Radius

• Frykman classification, AO/OTA classification
• Colles (dorsal tilt), Smith's (volar tilt), Barton's (intraarticular), die-punch
• Acceptable reduction criteria (volar tilt 0-22°, radial inclination >15°, ulnar variance ≤+1mm)
• Management: cast (undisplaced), ORIF with volar locking plate (displaced/intraarticular)
• Complications: malunion, EPL rupture, CRPS, median nerve symptoms
• Recent advance: arthroscopic-assisted reduction

6. Compartment Syndrome

• Pathophysiology: rising ICP → ischaemia → muscle necrosis → Volkmann's ischaemia
• Clinical features: 6 P's (Pain, Pressure, Paraesthesia, Paralysis, Pallor, Pulselessness - last 2 late signs)
• Diagnosis: compartment pressure >30mmHg or within 30mmHg of diastolic BP
• Whitesides technique for pressure measurement
• Treatment: remove compressive dressings → fasciotomy (4-compartment leg fasciotomy through 2 incisions)
• Late complication: Volkmann's ischaemic contracture - Holden classification

7. Fractures of Talus

• Hawkins classification (I - undisplaced, II - subtalar subluxation, III - complete dislocation, IV - TNJ dislocation)
• Blood supply of talus - deltoid branch (most important), artery of tarsal canal, artery of sinus tarsi
• Hawkins sign (subchondral osteopenia at 6-8 weeks) = good prognostic sign, indicates viable bone
• AVN rate: Hawkins I = 0-13%, II = 20-50%, III = 80-100%
• Management: ORIF (displaced), conservative (undisplaced)

8. ACL Injury

• Anatomy: anteromedial and posterolateral bundles
• Clinical tests: Lachman test (most sensitive), anterior drawer test, pivot shift test
• MRI findings
• Conservative vs surgical (reconstruction - autograft choices: BPTB vs hamstring)
• Double bundle vs single bundle reconstruction
• ACL in children: transphyseal vs physeal-sparing technique (April 2026)
• Complications: graft failure, cyclops lesion, tunnel widening

9. Fracture Shaft of Femur

• AO classification (transverse, oblique, spiral, comminuted)
• Emergency management: Thomas splint, skin/skeletal traction
• Definitive: Closed IMN (interlocking nail) - standard of care
• Nail mechanics: static vs dynamic locking
• Fat embolism syndrome - Gurd's criteria
• Complications: malrotation, non-union, knee stiffness

10. Calcaneum Fractures

• Essex-Lopresti classification: joint-depression type vs tongue type
• Sanders classification (CT-based, I-IV)
• Bohler's angle (normal 25-40°, reduced in fractures)
• Gissane's angle (normal 120-145°)
• Management: conservative (undisplaced, elderly, diabetic), ORIF via extensile lateral approach (Sanders II-III)
• Complications: peroneal tendon injury, wound dehiscence (10-25%), malunion, subtalar OA

Bonus High-Yield Short Notes for Paper II Trauma

• TENS (Titanium Elastic Nail System) - asked April 2026
• Burst fracture D12 with neurological deficit - asked April 2026
• Posterior malleolus fracture - asked April 2026
• Pathological fractures + Mirel's score - asked April 2026
• Hoffa's fracture - asked April 2026
• Gamekeeper's thumb (UCL injury) - asked April 2026
• Monteggia fracture (Bado classification)
• Galeazzi fracture
• Fat embolism syndrome
• Floating knee injury

Blood Supply of the Femoral Head

Structured Answer - 10 Marks (Essay + Viva Ready)

Introduction (1 mark)

Sources of Blood Supply (3 marks)

1. Medial Femoral Circumflex Artery (MFCA) - MOST IMPORTANT

• Branch of the deep femoral artery (profunda femoris), occasionally from the femoral artery directly
• Runs posteriorly between iliopsoas and pectineus, then between obturator externus and quadratus femoris
• At the superior border of quadratus femoris, it gives the deep branch which enters the posterior capsule
• Ascends along the femoral neck as retinacular vessels (posterosuperior and posteroinferior retinacular arteries) beneath the synovial reflection of the joint capsule
• Terminates as the lateral epiphyseal artery (also called the superior retinacular artery) - the single most important vessel to the femoral head in adults
• Supplies ~80% of the femoral head in adults
• Critical point: the MFCA deep branch passes just superior to the quadratus femoris muscle - this is why the quadratus femoris must NOT be completely transected during a posterior hip approach (Miller's Review, 9th Ed)

2. Lateral Femoral Circumflex Artery (LFCA)

• Also a branch of the profunda femoris
• Gives the inferior retinacular artery (anteroinferior retinacular vessels)
• Contributes minimally in adults - mainly supplies the anteroinferior head
• More important in neonates and infants

3. Artery of the Ligamentum Teres (Foveal Artery)

• Branch of the posterior division of the obturator artery (occasionally medial circumflex)
• Travels within the ligamentum teres to reach the fovea capitis on the femoral head
• Supplies only the area around the fovea (~10-15% of femoral head)
• Clinically insignificant in adults but important in children (up to 4 years)
• Can sustain the femoral head in hip dislocations if the retinacular vessels are disrupted

Age-Related Changes in Blood Supply (2 marks)

Anatomical Course and Retinacular Vessels (2 marks)

• After the MFCA gives its deep branch, it runs between the obturator externus below and the hip capsule above
• The vessels then travel along the femoral neck beneath the synovial reflection of the capsule (between capsule and bone)
• They are arranged in groups:
  • Posterosuperior retinacular vessels (most important) - from MFCA deep branch
  • Posteroinferior retinacular vessels - from MFCA
  • Anterosuperior and anteroinferior - from LFCA (minor)
• These vessels enter the bone at the subcapital region (head-neck junction)
• The entire pathway is intracapsular but extrasynovial

• Posterior capsulotomy can damage retinacular vessels → risk of AVN
• The capsule attaches at the intertrochanteric line anteriorly but only mid-neck posteriorly → the posterior neck is extracapsular

Clinical Correlations (2 marks)

1. Femoral Neck Fracture - Why AVN Occurs

• A displaced intracapsular femoral neck fracture (Garden III/IV) tears the retinacular vessels against the capsule
• Haematoma under the capsule can also cause tamponade of retinacular flow
• Subcapital fractures have higher AVN rates (20-30%) than basicervical (extracapsular - very low AVN risk)
• This is why time to surgery matters in young patients with displaced fractures - urgent reduction and fixation may restore perfusion before irreversible ischaemia

2. Hip Dislocation

• Posterior dislocation tears the posterosuperior retinacular vessels
• AVN rate after traumatic hip dislocation = 10-25%, higher if reduction is delayed >6 hours
• Reduction within 6 hours is the most important determinant of AVN prevention

3. SCFE (Slipped Capital Femoral Epiphysis)

• The slip occurs through the zone of hypertrophy at the physis
• Retinacular vessels on the posterosuperior neck are at risk → AVN in ~10-15% of cases
• Risk higher with unstable (acute on chronic) SCFE

4. Surgical Approach Implications

• Posterior approach (Kocher-Langenbeck): must preserve at least 50% of quadratus femoris to protect MFCA deep branch
• Pediatric IMN: avoid piriformis starting point → use trochanteric entry point to protect posterosuperior retinacular vessels
• Hip resurfacing arthroplasty: posterior approach must meticulously preserve the MFCA

5. Legg-Calve-Perthes Disease

• Idiopathic interruption of MFCA in children 4-8 years → AVN of capital epiphysis
• Because ligamentum teres supply is already negligible at this age, there is no collateral rescue

Summary Table for Quick Recall

Viva Questions & Model Answers

Course of the Medial Circumflex Femoral Artery (MFCA) - Diagrams

Diagram 1 - Overview: Origin from Profunda Femoris (Anterior View)

Diagram 2 - Anterior and Posterior Course with Cruciate Anastomosis

• Anterior view (left): MFCA passes medially between pectineus and iliopsoas, then between obturator externus and adductor brevis
• Posterior view (right): MFCA courses posteriorly to reach the trochanteric fossa, forming the cruciate anastomosis with LFCA transverse branch, inferior gluteal, and 1st perforating artery

Diagram 3 - Posterior View: MFCA giving Posterior Retinacular Arteries

Diagram 4 - Deep Dissection: MFCA passing Superior to Quadratus Femoris

Diagram 5 - CT Angiogram: Real Anatomy, Multiple Views

Summary of MFCA Course in One Line

Origin (profunda femoris) → passes medially between pectineus + iliopsoas → between obturator externus + adductor brevis → crosses superior border of adductor magnus → passes deep to quadratus femoris → enters posterior capsule as retinacular vessels → ascends along femoral neck as posterosuperior retinacular artery → enters femoral head at subcapital region as lateral epiphyseal artery

Recent Advances in Femoral Head Blood Supply & AVN

Exam-Ready Answer (add as final paragraph to any AVN / FNF / Blood Supply essay)

1. New Understanding of MFCA Anatomy

• Duplex ultrasonography and MR angiography can now non-invasively map the MFCA course pre-operatively, allowing surgeons to plan hip approaches with vessel preservation
• 3D CT angiography (as seen in Imaging Anatomy Atlas Vol 3) has confirmed that MFCA anatomical variants exist in up to 20% of patients - the MFCA may arise directly from the femoral artery rather than the profunda femoris
• Zone-specific retinacular vessel mapping has shown that the posterosuperior retinacular vessels enter the head at a consistent "safe zone" between 10 and 2 o'clock - this forms the basis of the Safe Surgical Dislocation approach (Ganz osteotomy)

2. Post-COVID AVN - A New Etiology (Very Exam-Relevant)

• Post-COVID AVN is now a recognised entity, asked directly in April 2026 Paper IV
• Systematic review of 104 patients (Hassan & Khalifa, Rheumatol Int 2023 - [PMID 37338665]):
  • Mean age 42.2 years - younger than typical AVN
  • 13 of 14 reports: corticosteroid use during COVID management was the primary culprit (mean prednisolone equivalent 1238 mg total)
  • 70.1% presented at Ficat Stage II at diagnosis
  • Most hips (80.8%) managed non-surgically with good outcomes if caught early
  • Mean interval from COVID diagnosis to AVN detection: 142 days - screening at 3-6 months post-COVID + steroid use is now recommended
• Other proposed mechanisms: COVID-19-related hypercoagulable state, direct vascular endothelial damage by SARS-CoV-2

3. Core Decompression - Still the Gold Standard for Early AVN, Now Enhanced

• Core decompression (Ficat I and II) remains first-line surgical treatment
• Enhanced by stem cell augmentation - the most important recent advance:
  • Meta-analysis of 11 RCTs + 7 retrospective studies, 1257 hips (Li et al., J Orthop Surg Res 2023 - [PMID 37533122]):
    • Lower femoral head collapse rate with CD + stem cells vs CD alone (P=0.001)
    • Lower THA conversion rate overall (P<0.0001)
    • Best results when stem cells are extracted (concentrated) + combined with mechanical support (structural graft)

4. Bone Marrow Stem Cell (BMSC) Therapy - Level 1 Evidence Now Available

• Most comprehensive meta-analysis of RCTs only (Novriansyah et al., PLoS One 2025 - [PMID 40554507]):
  • 10 RCTs, 593 patients, 779 hips
  • BMSC therapy significantly reduced femoral head collapse (OR 0.15, P<0.00001)
  • Reduced THA conversion rate (OR 0.20, P<0.00001)
  • Harris Hip Score improved by 10.7 points (MD=10.70, P<0.00001)
  • Pain (VAS) reduced by 8 points (P<0.00001)
  • 70% of included RCTs had low risk of bias - this is now high-quality evidence
• Technique: Bone marrow aspirated from iliac crest → centrifuged → concentrated BMSC injected into core decompression channel
• Mechanism: BMSCs differentiate into osteoblasts, secrete angiogenic growth factors (VEGF, bFGF), stimulate neovascularisation

5. Conservative / Pharmacological Advances

6. Vascularised Fibular Grafting - Updated Evidence

• Free vascularised fibular graft (FVFG) remains the preferred joint-preserving surgical option for pre-collapse AVN (Ficat II-III) in young patients
• Provides structural support AND vascular supply to the necrotic segment
• 10-year survivorship: ~70% in pre-collapse stages
• Recent modification: pedicled iliac crest graft (based on deep circumflex iliac artery) for smaller lesions

7. Surgical Trends - Global Perspective

• Corticosteroid use = #1 risk factor (75% of cases)
• THA is the dominant treatment (22.6% underwent THA within 1 year of diagnosis)
• Joint-preserving procedures declining in Western countries but increasing in younger patients
• Asian centres (South Korea, Japan) favour joint-preserving surgery more than Western centres - geographic variation is significant
• Call for consensus-driven international guidelines given this variation

8. Femoral Neck System (FNS) - New Implant to Protect Blood Supply

• FNS (Femoral Neck System) - asked directly as a short note in April 2026 Paper IV
• Single implant combining a sliding lag screw with an anti-rotation screw, inserted via a minimally invasive approach
• Advantage over sliding hip screw: smaller incision = less soft tissue disruption = less risk to retinacular vessels
• Advantage over 3 cannulated screws: better rotational control
• Indicated for: Garden I-II and selected Garden III-IV fractures in younger patients
• Early results: comparable to dynamic hip screw with potentially lower AVN rates (ongoing trials)

Viva Quick-Fire on Recent Advances

Garden Classification + Ficat Staging + FNS

Complete Exam Answer - Short Note / Viva Ready

1. GARDEN CLASSIFICATION of Femoral Neck Fractures (1961)

Key Points for Viva

• Garden I + II = Undisplaced → treat with internal fixation (3 cannulated screws or FNS)
• Garden III + IV = Displaced → in elderly: hemiarthroplasty or THA; in young (<60 yrs): urgent reduction + internal fixation
• Practical use: Interobserver agreement is poor across all 4 grades (only 22%) - but agreement is good when simplified to undisplaced (I+II) vs displaced (III+IV)
• Garden II is rare in practice - only 1.2% of femoral neck fractures in a large multicenter study of 1503 cases (Rockwood & Green 10th Ed)
• Garden Alignment Index (post-reduction check): AP 160°, lateral 180° - acceptable range AP 155-180°, lateral 155-180°

• In Garden IV, the head is completely free and rotates back to align with the acetabulum - the trabeculae look parallel/normal again on X-ray. The neck has displaced but the head has swung back. This paradox distinguishes it from Garden I (which is impacted in valgus).

2. FICAT CLASSIFICATION (Ficat & Arlet) of AVN of Femoral Head

Additional Classifications (Also Know These for Viva)

Memory Aid for Ficat:

"Normal → Sclerosis → Crescent → Collapse"

• Stage 1: Normal X-ray, abnormal MRI
• Stage 2: Sclerosis/cysts, still round head
• Stage 3: Crescent sign (the hallmark)
• Stage 4: Collapse + OA

3. FEMORAL NECK SYSTEM (FNS) - Recent Advance

What is FNS?

• A large-diameter sliding lag screw for compression along the femoral neck
• A small-diameter anti-rotation screw placed parallel to it (prevents rotational displacement)
• A short side plate with only 2 cortical screws in the shaft

How it Differs from Existing Implants

Evidence for FNS (from Campbell's 15th Ed)

• Biomechanical stability equal to DHS, superior to multiple cannulated screws
• Decreased rates of AVN compared to cannulated screws (less soft tissue damage = better retinacular vessel preservation)
• Decreased femoral neck shortening
• Less fluoroscopy use, better functional outcomes
• Systematic review and meta-analysis (Patel et al., Eur J Orthop Surg 2023): FNS leads to better outcomes than cannulated screws in adults

Indications for FNS

• Garden I and II (undisplaced) femoral neck fractures in any age
• Garden III-IV (displaced) in young patients (<60 years)
• High Pauwels angle fractures (Type III - most unstable, vertical fracture line) - where rotational control is most needed

Why FNS Protects Blood Supply Better

• Inserted via a small lateral incision over the trochanteric region
• No posterior dissection → retinacular vessels on the posterior neck are undisturbed
• No capsulotomy required
• Compare to: posterior approach for open reduction which risks the MFCA deep branch

Viva Quick-Fire