OR2.10-13 | Lower Limb Fractures — Graded Quiz

Correct. Delta pressure of 24 mmHg (<30 mmHg threshold) with clinical signs of compartment syndrome mandates immediate four-compartment leg fasciotomy. A palpable pulse does NOT exclude compartment syndrome — this is a critical exam trap.

Delta pressure (diastolic BP minus compartment pressure) <30 mmHg is the indication for fasciotomy regardless of pulse status. A palpable pulse does not exclude compartment syndrome — this is the most commonly tested known trap. Four-compartment leg fasciotomy (anterior, lateral, superficial posterior, deep posterior) must be performed emergently.

Delta pressure (diastolic BP − compartment pressure) = 72 − 48 = 24 mmHg, which is below the 30 mmHg threshold. Combined with clinical signs, immediate fasciotomy is mandatory even with a palpable pulse.

Correct. Early IMN (<24 hours) significantly reduces the incidence of fat embolism syndrome and ARDS compared with prolonged skeletal traction, by stabilising the fracture and reducing fat release from exposed marrow.

Early intramedullary nailing of femoral shaft fractures (<24 h) is associated with reduced incidence of fat embolism syndrome, pulmonary complications, and shorter hospital stay compared to prolonged skeletal traction or delayed surgery. Fat embolism risk is also reduced by avoiding excessive fracture manipulation.

Fat embolism syndrome risk is directly linked to early stabilisation of long bone fractures. Early IMN reduces fat embolic load from unstabilised fracture ends.

Correct. In a young, active patient with DIACF, ORIF is the treatment of choice. Surgery is delayed 5–10 days to allow 'wrinkle sign' to appear (indicating swelling has subsided), reducing wound complication risk from the lateral extensile approach.

Displaced intra-articular calcaneal fractures (DIACF) in young, active patients without significant swelling or systemic compromise are best treated with ORIF (lateral extensile approach). Non-operative management is acceptable in elderly, diabetics, or those with severe soft tissue injury. CT is essential for pre-operative planning.

In a young active patient with DIACF, conservative management leads to subtalar post-traumatic arthritis. ORIF is preferred but timing matters — wait for swelling to resolve (5–10 days) to reduce wound breakdown risk.

Correct. Jones fracture in an athlete is best treated with intramedullary screw fixation to accelerate healing, avoid non-union, and allow faster return to competitive sport compared with conservative management.

Jones fracture occurs at the proximal fifth metatarsal metaphyseal-diaphyseal junction and has a high non-union rate due to poor blood supply. It is distinguished from the avulsion (pseudo-Jones/dancer's) fracture of the styloid. In athletes, early surgery with intramedullary screw fixation is preferred to allow faster return to sport.

This is a Jones fracture (at the metaphyseal-diaphyseal junction), not an avulsion fracture of the styloid. Jones fractures in athletes are surgically treated with an intramedullary screw to reduce non-union risk and accelerate return to sport.

Correct. Weber C fractures are above the syndesmosis and always involve syndesmotic disruption. ORIF with restoration of fibular length and syndesmotic fixation (with a syndesomosis screw or tightrope) is required to stabilise the mortise.

Danis-Weber classification (A/B/C) is based on the fibular fracture level relative to the syndesmosis: A = below (trans/infra-syndesmotic, stable), B = at the level (variable stability), C = above the syndesmosis (trans-fibular, always involves syndesmotic rupture). Weber C always implies syndesmotic disruption and the ankle mortise is unstable.

Weber C fibular fractures occur above the syndesmosis and invariably involve syndesmotic disruption. The ankle mortise is unstable. ORIF with syndesmotic repair is mandatory.

Correct. Type III fractures traverse the physis and exit through the epiphysis into the joint. This injures the germinal (resting) and proliferative zones of the physis, which are responsible for longitudinal bone growth, directly threatening growth potential.

Salter-Harris Type III and IV fractures directly violate the germinal and proliferating zones of the physis when the fracture exits through the epiphysis/joint. This damages the physeal cartilage cells responsible for longitudinal growth. Type II exits through the metaphysis (not the physis-epiphysis junction) and thus less disrupts the germinal layer.

The key difference is where the fracture exits. Type II exits through the metaphysis — sparing the growth-critical germinal zone. Type III exits through the epiphysis — directly violating the germinal layer of the physis.

Correct. A 3 cm wound with severe contamination, periosteal stripping, and tissue loss is Gustilo Type IIIA (>1 cm, high energy, severe soft tissue injury with adequate bone coverage). IV antibiotics (cephalosporin + aminoglycoside) within 1 hour is the single most important intervention to prevent osteomyelitis.

Gustilo-Anderson classification: Type I: wound <1 cm, clean, minimal soft tissue damage; Type II: 1–10 cm, moderate soft tissue damage; Type IIIA: >10 cm but adequate soft tissue coverage; Type IIIB: >10 cm, extensive soft tissue loss requiring flap coverage; Type IIIC: any size with arterial injury requiring repair. Antibiotics (first-generation cephalosporin for I/II, add aminoglycoside for III, add penicillin for farm injuries) must be administered within 1 hour of injury.

3 cm wound + heavy contamination + periosteal stripping + tissue loss = Gustilo Type III. Without vascular injury, this is IIIA. The critical intervention is IV antibiotics within 1 hour of injury — delay significantly increases infection risk.

Correct. The standard threshold for fixing the posterior malleolus is a fragment involving ≥25% of the articular surface. Beyond this, joint contact mechanics are significantly disrupted and there is increased risk of post-traumatic arthritis if left unreduced.

The posterior malleolus is fixed when it involves >25–33% of the articular surface (most guidelines use 25% as the threshold). Fragments above this threshold reduce the contact area of the tibiotalar joint, increase joint contact stress, and predispose to post-traumatic arthritis. Fixation also reduces re-displacement and allows earlier mobilisation.

The widely accepted threshold for posterior malleolus fixation is a fragment involving ≥25% of the tibiotalar articular surface. A fragment involving 35% in this question exceeds this threshold and should be fixed.

Correct. A distal femoral locking compression plate (LCP) provides angular stability through locked screws in osteoporotic bone and accommodates the comminuted intercondylar extension. It allows anatomical reduction of the articular surface while minimising soft tissue stripping.

Distal femur fractures (AO type C — supracondylar with intercondylar extension) are best treated with a distal femoral locking plate (DFLP) or retrograde intramedullary nail. In osteoporotic bone with comminution, a locking plate provides angular stability as screws lock into the plate. The locking plate is particularly superior to conventional plating in osteoporotic or comminuted fractures.

A DHS is designed for proximal femur fractures. An antegrade nail does not address the intercondylar extension. Conservative management in osteoporotic elderly patients leads to malunion and prolonged immobilisation. The distal femoral LCP is the correct implant.

Correct. Closed intramedullary interlocking tibial nailing is the gold standard for displaced closed tibial shaft fractures in young active patients. It provides stable fixation, preserves the periosteal blood supply, and allows early weight-bearing and mobilisation.

Closed displaced tibia fractures in adults are best treated with intramedullary nailing (Kuntscher/interlocking nail). IMN preserves the soft tissue envelope, allows load sharing, and permits early weight-bearing. Conservative management (cast) is reserved for minimally displaced fractures. Plating carries high infection risk due to poor soft tissue cover over the subcutaneous tibia.

For a displaced closed both-bones leg fracture in a young adult, IMN is the definitive treatment of choice. Cast management cannot maintain alignment; primary open plating risks infection; external fixation is a temporising device.