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OR2.14-16 | Fracture Complications and Special Situations — PBL Case

CLINICAL SETTING

Ramu, a 38-year-old farmer from a rural district, arrives at the tertiary orthopaedic centre accompanied by his wife. Six months ago he sustained a compound fracture of the right tibia when his tractor overturned in a field. He was taken to the nearest primary health centre, where the wound was cleaned and an above-knee plaster applied. He was given 'some tablets' and discharged without any specialist consultation. He returns today with a draining sinus over the anterior tibia, persistent pain, inability to bear weight, and what his wife describes as 'the bone not healing'. On examination, temperature 37.8°C, pulse 92/min. The right lower leg has a discharging sinus with purulent material over the fracture site, localised warmth, and palpable instability at the mid-shaft. The dorsalis pedis pulse is present. Laboratory results: Haemoglobin 9.2 g/dL, WBC 13,400/mm³ (neutrophils 78%), ESR 88 mm/hr, CRP 62 mg/L. Plain X-rays of the right tibia show no bridging callus, sclerotic bone ends with a medullary opacity, and periosteal reaction — a 'dead bone' sequestrum is suspected.

Trigger 1: The initial injury and the 'missed window'

The triage nurse retrieves old records showing that at the time of injury, the wound was described as '8 cm, heavily contaminated with soil, comminuted fracture fragments, and muscle tissue exposed'. The patient received oral amoxicillin and was sent home. The wound was re-dressed every 3 days at a local clinic. No vascular assessment was documented. No specialist referral was made for 3 months.

DISCUSSION POINTS

  • Using Gustilo-Anderson criteria, how would you classify this open fracture? What grade/subtype and why?
  • What is the correct antibiotic protocol for this fracture type — drug, route, and critical timing? Why is a 1-hour window described as essential?
  • What neurovascular assessment should have been done at first presentation, and what specific complications could have been missed by the primary health centre team?
  • Why is oral amoxicillin at home inadequate management for a Grade IIIA open fracture?
Click to reveal Trigger 2: Six months later — non-union or infection or both? (discuss previous trigger first!)

Trigger 2: Six months later — non-union or infection or both?

The registrar suspects infected non-union. Advanced investigations are ordered. MRI of the tibia shows intramedullary signal change extending 6 cm around the fracture, with periosteal oedema and a cortical sequestrum. Three-phase Tc-99m bone scan shows markedly reduced uptake at the fracture ends compared to adjacent diaphysis. Biopsy is performed: histology shows necrotic bone with inflammatory cells; culture grows Staphylococcus aureus (MRSA, sensitive to vancomycin).

DISCUSSION POINTS

  • How do you use the MRI and bone scan findings together to classify the type of non-union and characterise the infection?
  • What does 'reduced uptake on bone scan' tell you about this bone's viability, and how does this influence the surgical plan?
  • Outline the four pillars of management for infected non-union — antibiotic strategy, débridement, fixation, and reconstruction.
  • Why is the Ilizarov (circular external fixator) technique particularly suited to infected non-unions with segmental bone loss?
Click to reveal Trigger 3: The son in the next bay — a paediatric parallel (discuss previous trigger first!)

Trigger 3: The son in the next bay — a paediatric parallel

As the team discusses Ramu's case, a 7-year-old boy, Arjun, is admitted to the adjacent bay. He fell from a tree onto an outstretched hand. X-ray shows a Gartland Type III supracondylar fracture of the humerus with significant posterior displacement. The house officer notes: radial pulse present, capillary refill 2 s, but the child is crying with intense forearm pain and extension of the fingers causes the child to scream. The compartment is tense on palpation.

DISCUSSION POINTS

  • List the neurovascular structures most at risk in supracondylar fractures and describe the specific clinical test for each.
  • A present radial pulse is documented. Does this exclude vascular compromise or compartment syndrome? What is the physiological basis for this 'present-pulse trap'?
  • What is the delta-pressure threshold for emergency fasciotomy in suspected compartment syndrome and what is the immediate management algorithm?
  • Separately, Arjun's 4-year-old sister was also brought in — she is holding her right arm in adduction, slight flexion, and pronation after a caregiver pulled her hand to prevent a fall. X-rays are normal. What is the diagnosis, the reduction technique, and how do you counsel the family to prevent recurrence?

Learning Issues

Research these questions and bring your findings to the discussion.

  1. [OR2.15] What are the Gustilo-Anderson Grade III subtypes? What is the critical time window for IV antibiotics in open fractures and why? What antibiotic regimen is recommended for each grade?
  2. [OR2.14] How are malunion, delayed union, and non-union defined? What investigations distinguish infected from aseptic non-union, and atrophic from hypertrophic non-union? What are the surgical options for infected non-union with segmental bone loss?
  3. [OR2.16] What are the neurovascular complications of supracondylar humerus fractures in children (AIN, median nerve, brachial artery)? Why does a present radial pulse not exclude vascular compromise or compartment syndrome? How is compartment syndrome diagnosed and treated? What is the Salter-Harris classification, its types, and the implications of each for growth? What is pulled elbow (nursemaid's elbow) and how is it managed?