Orthopaedics

Definition & Surgical Importance

A fracture of the neck of the femur is an intracapsular fracture occurring between the femoral head and the intertrochanteric line. It is common in the elderly osteoporotic patient after a trivial fall, and in the young only after high-energy trauma. Its importance lies in the precarious blood supply of the femoral head, which is largely intracapsular — hence a high incidence of avascular necrosis (AVN) and non-union.

Blood Supply of the Femoral Head (why it matters)

Three sources supply the head: (1) the retinacular vessels from the medial and lateral circumflex femoral arteries (the dominant supply, running in the capsule up the neck — torn in displaced fractures); (2) the artery of the ligamentum teres (foveal artery — minor, often absent in the elderly); and (3) intra-osseous vessels from the shaft (interrupted at the fracture line). A displaced intracapsular fracture therefore strips the head of its blood supply, explaining AVN.

Classification

Garden classification (by displacement): Type I incomplete/impacted (valgus); Type II complete but undisplaced; Type III complete with partial displacement (trabeculae malaligned); Type IV complete with full displacement (head free, trabeculae parallel again). Pauwels classification (by the angle of the fracture line to the horizontal): Type I <30°, Type II 30–50°, Type III >50° — the more vertical, the greater the shear and the higher the failure rate. Anatomically: subcapital, transcervical and basicervical.

Clinical Features

The patient is unable to bear weight after a fall; the limb is shortened, adducted and externally rotated (about 45°, less than the 90° of trochanteric fractures because the intact capsule limits rotation). There is pain in the groin, tenderness over Scarpa's triangle, and pain on axial (heel) percussion. An impacted (Garden I) fracture may still allow limited weight-bearing — a trap.

Investigations

AP pelvis and lateral (cross-table) radiographs of the affected hip. Shenton's line is broken. Look for the fracture line and disruption of the trabecular pattern. MRI is the investigation of choice for a suspected occult fracture. Routine pre-operative work-up (bloods, ECG, chest radiograph) is essential as most patients are elderly with comorbidities.

Management

Undisplaced (Garden I & II): internal fixation with three cannulated cancellous screws in an inverted-triangle configuration. Displaced (Garden III & IV): treatment depends on age and physiological status. In the young adult the head must be salvaged — emergency closed/open reduction and internal fixation within a few hours to reduce AVN risk. In the elderly, arthroplasty is preferred: hemiarthroplasty (bipolar/unipolar) for the frail, low-demand patient, and total hip replacement for the fit, active, independent patient (better function, lower re-operation). Surgery is ideally performed within 48 hours to reduce mortality and complications. Early mobilisation, DVT prophylaxis and osteoporosis treatment complete the plan.

Complications

Early: general complications of recumbency in the elderly (chest infection, DVT/PE, pressure sores, delirium), and high one-year mortality. Late: avascular necrosis (up to 30% of displaced fractures, may appear 1–3 years later), non-union, and secondary osteoarthritis.

• Intracapsular fracture → precarious blood supply → high AVN & non-union.
• Garden I–II = undisplaced; III–IV = displaced. Pauwels grades by verticality.
• Limb shortened, adducted, externally rotated ~45°.
• Young + displaced = emergency ORIF (salvage head). Elderly + displaced = arthroplasty.
• Operate within 48 h; treat osteoporosis; give DVT prophylaxis.

Definition

An intertrochanteric (pertrochanteric) fracture is an extracapsular fracture of the proximal femur running between the greater and lesser trochanters. It is one of the commonest fractures in the elderly osteoporotic patient. Because the region is cancellous and richly vascular, union is the rule and avascular necrosis is rare — the problems here are blood loss, malunion (coxa vara) and implant failure, not non-union.

Mechanism & Clinical Features

Usually a fall on the greater trochanter in an elderly woman. The limb is markedly shortened and externally rotated (~90°) — more than in an intracapsular fracture because there is no intact capsule to restrain rotation. There is swelling, bruising and severe tenderness over the trochanter; the patient cannot bear weight. Significant blood loss into the thigh can cause hypovolaemia.

Classification

Boyd and Griffin and Evans classifications describe the pattern. The key clinical distinction is stable vs unstable. Stability depends on the integrity of the posteromedial cortex (calcar): comminution of the posteromedial fragment, a reverse oblique line, or subtrochanteric extension makes the fracture unstable and prone to collapse into varus.

Investigations

AP pelvis and lateral hip radiographs demonstrate the fracture and its comminution. Assess the posteromedial cortex and any reverse-oblique component for stability. Full pre-operative assessment and correction of anaemia/dehydration are important given the elderly population and blood loss.

Management

Treatment is almost always operative to allow early mobilisation and avoid the lethal complications of recumbency. Options:
• Dynamic hip screw (DHS) — a lag screw in the head connected to a side-plate on the shaft. It allows controlled dynamic impaction at the fracture, ideal for stable patterns.
• Cephalomedullary nail (PFN / PFNA / Gamma nail) — an intramedullary device with a cephalic screw/blade; the shorter lever arm and load-sharing make it the implant of choice for unstable, reverse-oblique and subtrochanteric patterns.
• Arthroplasty is reserved for selected cases (e.g. severe comminution with poor bone or pre-existing arthritis). Surgery should ideally occur within 48 hours, with DVT prophylaxis, early weight-bearing and osteoporosis management.

Subtrochanteric Extension

A fracture involving the region within 5 cm below the lesser trochanter is subtrochanteric. This is a high-stress area of predominantly cortical bone subjected to large compressive (medial) and tensile (lateral) forces, so it is prone to varus malunion and implant failure. A long cephalomedullary nail is the implant of choice. An ‘atypical’ subtrochanteric fracture (transverse, lateral cortical beaking) should raise suspicion of prolonged bisphosphonate use.

Peri-operative Care & Rehabilitation

Because these are frail, elderly patients, outcome depends as much on medical co-management as on the surgery: correction of anaemia and dehydration, analgesia, delirium prevention, pressure-area care, DVT prophylaxis and early nutritional support. Ortho-geriatric shared care and surgery within 48 hours reduce mortality. Post-operatively the aim is immediate weight-bearing as tolerated with physiotherapy, and secondary fracture prevention with calcium, vitamin D and bone-protection therapy.

Complications

General complications of immobility and high one-year mortality in the frail elderly. Mechanical: coxa vara / malunion from collapse of an unstable fracture, lag-screw cut-out, and implant breakage. Non-union and AVN are uncommon because of the good blood supply.

• Extracapsular → good blood supply → unites well; AVN & non-union rare.
• Limb shortened + externally rotated ~90° (more than intracapsular).
• Stability hinges on the posteromedial cortex (calcar).
• Stable → DHS; unstable / reverse-oblique / subtrochanteric → cephalomedullary nail.
• Avoid cut-out: good reduction + central deep screw + TAD < 25 mm.

Definition & Importance

A fracture of the shaft of the femur involves the diaphysis between the subtrochanteric region and the supracondylar region. The femur is the largest and strongest bone, so a shaft fracture usually implies high-energy trauma (road-traffic accident, fall from height) in a young adult, or a trivial injury on pathological/osteoporotic bone. It is important for two reasons: substantial blood loss (1–1.5 L into the thigh, more if bilateral or open) that can cause hypovolaemic shock, and the risk of fat embolism syndrome.

Deforming Forces

The powerful thigh muscles displace the fragments predictably. The proximal fragment is flexed (iliopsoas), abducted (glutei) and externally rotated; the distal fragment is pulled into adduction and varus by the adductors and flexed posteriorly by gastrocnemius (a danger to the popliteal vessels in supracondylar extensions). Understanding these forces guides reduction.

Clinical Features

Severe pain, swelling and deformity of the thigh with shortening and inability to bear weight; abnormal mobility and crepitus. Because of the energy involved, assess for shock and always look for associated injuries — ipsilateral hip/neck-of-femur fracture, knee ligament injury, and (critically) distal neurovascular status.

Investigations

AP and lateral radiographs of the whole femur including the hip and knee joints — never image the shaft alone. Assess comminution, segmental patterns and pathological features. Trauma work-up (FAST/CT) as indicated by the mechanism.

Management

First aid / resuscitation: ATLS principles, control haemorrhage, splint the limb (Thomas splint) for pain relief and to reduce blood loss and fat embolism, and give analgesia.
Definitive: in adults the treatment of choice is closed intramedullary interlocking nailing — it is load-sharing, permits early mobilisation and gives high union rates. Antegrade or retrograde nails are used depending on the fracture and associated injuries. Plating or an external fixator (as damage control in the unstable polytrauma patient or open fracture) are alternatives. In children, treatment is largely conservative/age-dependent — Pavlik harness or hip spica in infants, and titanium elastic nails or submuscular plating in older children.

Complications

Early: hypovolaemic shock, fat embolism syndrome, and (rarely) vascular or nerve injury. Late: delayed/non-union, malunion (shortening, malrotation, angulation), knee stiffness from quadriceps adhesions, and infection after open injury or surgery. Refracture may follow premature implant removal.

• High-energy injury in the young; watch for shock and fat embolism.
• Proximal fragment flexed/abducted; distal fragment adducted (varus) & flexed.
• Always X-ray the whole femur with hip and knee; exclude ipsilateral neck fracture.
• Splint with Thomas splint; definitive Rx = closed interlocking IM nailing in adults.
• Children treated conservatively / age-appropriate (spica, elastic nails).

Definition

A fracture of both bones of the leg denotes a fracture of the shafts of the tibia and fibula. The tibia is subcutaneous along its whole anteromedial border, so these are frequently open (compound) fractures with a high risk of infection, delayed union and the surgical emergency of acute compartment syndrome.

Mechanism

Two broad patterns: a direct blow (bumper injury, RTA) causing a transverse or comminuted fracture at the same level, often open; and an indirect (twisting) force producing a spiral fracture of the tibia and fibula at different levels. High-energy fractures carry the greatest risk of soft-tissue compromise.

Clinical Features

Pain, swelling, deformity and inability to bear weight; the sharp subcutaneous tibial crest may tent or pierce the skin. Examine the skin (open wound), the neurovascular status (dorsalis pedis and posterior tibial pulses, deep peroneal sensation in the first web space) and — repeatedly — for compartment syndrome.

Acute Compartment Syndrome — the critical complication

Bleeding and oedema within an unyielding osteofascial compartment raise the interstitial pressure until it exceeds capillary perfusion pressure, causing ischaemia of muscle and nerve. The cardinal sign is pain out of proportion to the injury, worsened by passive stretch of the compartment muscles. The classical late “5 Ps” (pain, paraesthesia, pallor, pulselessness, paralysis) are unreliable — pulses are usually present until very late. Diagnosis is clinical; if in doubt, measure compartment pressure (a within 30 mmHg of diastolic — i.e. low ΔP — indicates the need to decompress).

Investigations

AP and lateral radiographs of the whole tibia including knee and ankle joints. Classify open fractures by the Gustilo–Anderson grade. Check haemoglobin and renal function; myoglobinuria suggests muscle necrosis.

Management

Closed, low-energy fractures that are stable and acceptably aligned may be treated in an above-knee cast (later a functional Sarmiento brace). Displaced, unstable or open fractures are treated operatively: closed intramedullary interlocking nailing is the workhorse for closed and low-grade open tibial shaft fractures; external fixation is preferred for severe open (Gustilo IIIB/C) injuries and damage control. Open fractures require urgent antibiotics, tetanus prophylaxis, thorough debridement and early soft-tissue cover. Fasciotomy is performed the moment compartment syndrome is suspected.

Complications

Compartment syndrome and its sequela of ischaemic contracture; infection and osteomyelitis (especially in open fractures); delayed and non-union (the distal third has a poor blood supply); and malunion. The fibula, being non-weight-bearing, often unites uneventfully.

• Tibia is subcutaneous → high rate of open fractures & delayed union.
• Acute compartment syndrome = pain out of proportion + pain on passive stretch.
• Pulses present until late — do not wait for the 5 Ps.
• Treatment of compartment syndrome = emergency 4-compartment fasciotomy.
• Closed stable → cast; unstable/open → IM nail or external fixator; open → debride + cover.

Definition & Surgical Anatomy

Ankle injuries range from ligamentous sprains to fracture-dislocations of the ankle mortise — the socket formed by the distal tibia (plafond and medial malleolus), the fibula (lateral malleolus) and the strong syndesmotic ligaments that bind them, into which the talus sits. Stability depends on both the bony malleoli and the medial (deltoid), lateral and syndesmotic ligaments. A congruent mortise is essential — even a 1–2 mm lateral shift of the talus markedly reduces the contact area and predisposes to arthritis.

Mechanism & Classification

Most ankle fractures follow a rotational injury of the foot on the leg. Two classifications are used. The Danis–Weber classification is based on the level of the fibular fracture relative to the syndesmosis (simple and surgically useful). The Lauge-Hansen classification describes the mechanism by foot position and force direction (e.g. supination-external rotation, the commonest).

Clinical Features

Pain, swelling and inability to bear weight after a twisting injury; deformity in fracture-dislocations. Palpate for tenderness at both malleoli, the medial and lateral ligaments and — importantly — the proximal fibula (Maisonneuve). Assess the skin (fracture blisters, threatened skin over a displaced fragment) and the neurovascular status. The Ottawa ankle rules help decide who needs radiographs.

Investigations

AP, lateral and mortise-view radiographs of the ankle. Assess the talar shift, the medial clear space, and symmetry of the mortise. Radiograph the full length of the fibula if a Maisonneuve injury is suspected. CT helps in complex or posterior malleolar/pilon patterns.

Management

Stable, undisplaced fractures (most Weber A and undisplaced B without talar shift) are treated conservatively in a below-knee cast or walking boot with a period of protected weight-bearing. Unstable / displaced fractures (talar shift, displaced bimalleolar or trimalleolar, most Weber C) require open reduction and internal fixation to restore an anatomically congruent mortise — lateral malleolus with a plate and screws, medial malleolus with screws or a tension band, and syndesmotic stabilisation (screw or suture-button) where disrupted. A fracture-dislocation should be reduced urgently to relieve pressure on the skin and neurovascular structures.

Ankle Sprains & the Ottawa Rules

The commonest ankle injury is a lateral ligament sprain from an inversion force, injuring the anterior talofibular ligament (ATFL) first, then the calcaneofibular ligament. Sprains are graded I (stretch), II (partial tear) and III (complete tear with instability). The Ottawa ankle rules guide the need for radiographs: image only if there is bony tenderness at the posterior edge or tip of either malleolus, tenderness at the navicular or base of the fifth metatarsal, or an inability to bear weight for four steps both immediately and in the department. Most sprains are managed with the PRICE/POLICE regimen (protection, optimal loading, rest, ice, compression, elevation) and early rehabilitation; complete tears with instability occasionally need repair.

Complications

Post-traumatic osteoarthritis (from an incongruent mortise or residual talar shift) is the commonest late problem; also stiffness, malunion, non-union of the medial malleolus, wound problems over the subcutaneous fibula, and chronic instability after ligamentous injuries.

• Stability of the mortise depends on the malleoli + deltoid/syndesmotic ligaments.
• Weber A (below) → C (above) — higher fibular # = more syndesmotic disruption/instability.
• Even 1–2 mm talar shift halves contact area → arthritis; restore the mortise anatomically.
• Stable/undisplaced → cast; unstable/displaced → ORIF ± syndesmotic fixation.
• Examine the proximal fibula (Maisonneuve); reduce a fracture-dislocation urgently.