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OR10.1,OR11.1 | Bone Tumours and Peripheral Nerve Injuries — Assignment

CLINICAL SCENARIO

This assignment develops your ability to systematically evaluate a patient with a suspected malignant bone tumour, apply the Enneking staging system, and formulate a management plan that integrates surgical principles with oncological care. You will also address the implications of a nerve injury that may accompany your case.

Instructions

  1. Read the clinical scenario provided below.
  2. Identify the most likely diagnosis and justify it using the history, examination, and imaging findings.
  3. Apply the Enneking surgical staging system to classify the tumour (grade, local extent, metastases).
  4. Outline the biopsy plan — type, approach, and why the tract must lie within the resection field.
  5. Describe the multidisciplinary management: neoadjuvant chemotherapy (if applicable), surgical margin required, reconstruction options, and adjuvant treatment.
  6. Address any peripheral nerve injury associated with the case: classify by Seddon/Sunderland grade, specify the expected deformity and sensory deficit, and recommend splinting.
  7. Discuss one key prognostic factor and how it influences expected outcomes.

Clinical Scenario: A 16-year-old boy presents with 6 weeks of worsening pain and a firm swelling over the lateral distal femur. X-ray shows a mixed lytic-sclerotic metaphyseal lesion with a Codman's triangle and mild soft tissue extension; no regional lymph node enlargement. On neurological examination, there is mild foot drop and sensory loss over the dorsum of the foot on the same side.

Length: 600–900 words

What to Submit

Diagnosis and Radiological Interpretation

Guidance: State the most likely diagnosis. Describe the specific X-ray features (sunburst/Codman's triangle, location — metaphysis vs diaphysis vs epiphysis) that support your diagnosis and distinguish it from the main differential diagnoses (Ewing's sarcoma, GCT). Reference the patient's age and typical tumour demographics.

Enneking Surgical Staging

Guidance: Apply the Enneking staging system: Step 1 — histological grade (G1 low vs G2 high); Step 2 — local extent (T1 intracompartmental vs T2 extracompartmental); Step 3 — distant metastasis (M0 vs M1). Assign a stage (IA, IB, IIA, IIB, III) and state what staging investigations are required (MRI, CT chest, bone scan/PET). Justify each component.

Biopsy Planning

Guidance: Specify the biopsy technique (core-needle vs open incisional) and the planned surgical approach for the definitive resection. Explain clearly why the biopsy tract must be longitudinal and lie within the planned resection line (Mankin principle). Describe what would happen if the biopsy were placed in the wrong compartment.

Multidisciplinary Management Plan

Guidance: Describe the management sequence: neoadjuvant chemotherapy regimen and its rationale (shrink tumour, treat micrometastases, assess chemo-sensitivity); surgical wide excision with limb salvage (distal femoral replacement or allograft options); adjuvant chemotherapy. Specify the required surgical margin (wide, with normal tissue cuff) per the Enneking stage.

Peripheral Nerve Injury — Classification and Splinting

Guidance: Classify the foot drop using both Seddon (neurapraxia/axonotmesis/neurotmesis) and Sunderland (I–V) grading systems. Identify the nerve involved and the probable mechanism. Describe the expected motor and sensory deficits. Recommend the appropriate splint (ankle-foot orthosis/foot drop splint) and state at what electrophysiological timepoint nerve conduction studies should be repeated.

Grading Rubric — Bone Tumours and Peripheral Nerve Injuries Assignment Rubric
Criterion Points Full-marks descriptor
Diagnosis and Radiological Reasoning 10 pts Correct diagnosis with precise description of all key X-ray features (Codman's triangle, sunburst, metaphyseal location), clear differentiation from Ewing's and GCT using radiological and demographic criteria.
Enneking Staging Application 10 pts Correct stage assigned (IIB) with precise justification for each component (G2 high grade, T2 extracompartmental, M0) and full listing of required staging investigations.
Biopsy Planning and Oncological Principles 10 pts Correct biopsy technique stated with explicit explanation of Mankin principle (longitudinal incision in the resection field), consequences of wrong-compartment biopsy, and recommendation that the operating tumour surgeon performs the biopsy.
Multidisciplinary Management Plan 10 pts Complete MDT plan with neoadjuvant chemotherapy rationale, wide surgical margin for limb salvage, reconstruction option, adjuvant chemotherapy, and MDT composition (orthopaedic oncologist, medical oncologist, radiologist, pathologist, physiotherapist).
Nerve Injury Classification and Rehabilitation 10 pts Common peroneal nerve correctly identified; Seddon/Sunderland grading applied with justification; correct deformity (foot drop) and sensory pattern described; foot drop splint (AFO) recommended with appropriate NCS follow-up timeline.

PEER REVIEW

Review your peer's assignment using the rubric above. For each criterion, assign a score and write 2–3 specific sentences explaining your rating — cite exact claims in their response where possible. Conclude with one overall strength and one constructive suggestion for improvement. Your peer review should be 200–300 words.