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Morton’s Neuroma
Perineural fibrosis of the common plantar digital nerve—classically in the 3rd webspace—causing burning plantar forefoot pain. Provocative tests: web‑space compression, Mulder’s click (palpable snap with medial–lateral squeeze), sensory symptoms into adjacent toes. Initial management is non‑operative: wide toe‑box shoes, metatarsal pads, activity modification; steroid injections provide short‑term relief; ultrasound‑guided ablation/PRP considered. Failure of conservative care → neurectomy of the...
Open topicMulti-ligament Knee Injury
Involves disruption of ≥2 major knee ligaments; often from high-energy trauma. Common patterns: ACL + PCL ± collateral injuries. Associated with vascular (popliteal artery) and nerve (common peroneal) injuries. Diagnosis: clinical + MRI; check vascular status with ABI, Doppler, CTA. Management: emergent reduction, vascular repair if injured, staged ligament reconstruction.
Open topicMultiple Myeloma — Orthopaedic View
Most common primary malignant bone tumor in adults (median age ~65 yrs). Neoplastic proliferation of plasma cells → monoclonal immunoglobulin production. Classical CRAB features: hyperCalcemia, Renal failure, Anemia, Bone lesions. Radiology: multiple punched-out lytic lesions, diffuse osteopenia. Diagnosis: SPEP/UPEP (M protein, Bence-Jones), bone marrow biopsy (>10% plasma cells). Ortho role: prophylactic fixation of impending fractures (Mirel’s >8), spinal decompression, bisphosphonates, verte...
Open topicMultiple Myeloma & Plasmacytoma
Most common primary malignant tumor of bone (plasma cell dyscrasia). CRAB features: hyperCalcemia, Renal failure, Anemia, Bone lesions (lytic). X‑ray: punched‑out lytic lesions, diffuse osteopenia, vertebral collapse. Diagnosis: serum/urine electrophoresis (M‑protein), bone marrow plasma cells >10%. Treatment: systemic chemotherapy (bortezomib, lenalidomide, dexamethasone), bisphosphonates, SCT in eligible patients.
Open topicMusculoskeletal Infections — Algorithm
Spectrum: cellulitis, abscess, septic arthritis, osteomyelitis. Principles: Early recognition, debridement, targeted antibiotics, stabilization, soft‑tissue cover. Diagnosis algorithm: suspect → labs (WBC, ESR, CRP) → imaging (X‑ray, MRI) → aspiration/biopsy for culture → tailored therapy. Surgical principles: remove necrotic tissue, maintain stability, provide vascularized soft‑tissue coverage. Antibiotics: empiric broad‑spectrum → targeted based on culture, prolonged course in bone infections.
Open topicMyositis Ossificans
Heterotopic ossification in muscle after trauma or neurological injury. Common sites: quadriceps, brachialis, adductors. Symptoms: painful swelling → hard mass, ↓ROM. Radiology: peripheral calcification with central lucency (zoning). Treatment: rest, NSAIDs, physio; excision after maturation (>6–12 mo).
Open topicNavicular & Cuboid Fractures
Tarsal navicular: body, tuberosity, and stress fractures; critical for medial column length and talonavicular congruity. Cuboid: 'nutcracker' fracture from forefoot abduction; lateral column length is key. Imaging: weight-bearing AP/lat/oblique + CT; MRI for stress fractures. Indications for surgery: displacement >2 mm, articular incongruity, medial/lateral column shortening, and instability with Lisfranc involvement. Fixation: screws/mini-plates for navicular; bridging plate/ex-fix for cuboid r...
Open topicNerve Entrapments — Cubital Tunnel Syndrome
Second most common compression neuropathy after CTS; affects ulnar nerve at elbow. Symptoms: paresthesias in ulnar digits, weakness of intrinsic hand muscles. Tests: Tinel’s at elbow, elbow flexion test, Froment’s sign, Wartenberg’s sign. Investigations: NCS/EMG confirm slowed conduction across elbow. Management: activity modification, splinting; surgical decompression/transposition if persistent.
Open topicNonunion — Weber & Cech Classification
Viable (hypertrophic/oligotrophic) vs non‑viable (atrophic, necrotic, defect, comminuted). Radiographic callus indicates biology; absence suggests poor biology. Guides treatment: stability alone for viable; add graft/biologics for non‑viable. viable → improve stability; nonviable → improve stability + add biology.
Open topicNonunion & Bone Transport — Ilizarov
Ilizarov fixator allows bone transport for segmental loss. Principle: distraction osteogenesis by gradual tension on callus. Indications: infected nonunion, bone loss, deformity correction. Protocol: latency 5–7 days, distraction 1 mm/day (0.25×4). Complications: pin site infection, joint stiffness, regenerate problems.
Open topicNuclear Medicine — Bone Scan & PET Basics
Bone scan = radionuclide (Tc-99m MDP) uptake proportional to osteoblastic activity. Highly sensitive for metastasis, stress fractures, infection, AVN. PET (FDG-PET): measures metabolic activity (glucose uptake). PET superior for staging malignancy, differentiating benign vs malignant lesions. Limitations: false positives (arthritis, trauma, infection).
Open topicO’Brien / Metaizeau — Paediatric Radial Neck Fractures
O’Brien Angulation: I (60°). Displacement/translation also matters; >3 mm or severe angulation predicts need for reduction/fixation. Metaizeau (elastic stable intramedullary nailing) classification is treatment-oriented with percutaneous leverage, intramedullary nail reduction, or open reduction for severely displaced injuries.
Open topicOpen Fractures — BOAST Principles
BOAST 4 guidelines: antibiotics ASAP, tetanus, debridement, stabilization, soft tissue cover. Do not remove bone fragments unless grossly non-viable. Definitive cover within 72 h (preferably 48). Stabilization with external fixator/IM nail/plate as appropriate. Complications: infection, nonunion, flap failure.
Open topicOrthopaedic Implants — Materials & Corrosion
Common alloys: 316L stainless, cobalt‑chrome, titanium (Ti‑6Al‑4V). Corrosion mechanisms: fretting at modular junctions, crevice under plates, galvanic with dissimilar metals. Clinical sequelae: metal ion release, ALVAL, osteolysis, trunnionosis in THA. Prevention: material pairing, surface finish, avoiding fluid‑filled crevices, firm taper assembly.
Open topicOrthoses — Lower Limb (KAFO/AFO)
AFO: ankle-foot support in drop foot, CP, polio. KAFO: supports knee in quadriceps paralysis, SCI. Types: rigid, hinged, leaf-spring (AFO); locked, drop lock, offset (KAFO). Goals: prevent deformity, support gait. Complications: sores, stiffness.
Open topicOsgood–Schlatter Disease
Apophysitis of tibial tubercle in adolescents due to repetitive traction from quadriceps. Common in athletic boys (10–15 yrs). Clinical: pain, swelling, prominent tender tibial tubercle. X-ray: fragmentation and irregularity of tibial tubercle apophysis. Treatment: activity modification, stretching, NSAIDs; resolves with skeletal maturity.
Open topicOsteochondral Autograft Transfer (OATS)
Cartilage repair technique for focal chondral defects
Open topicOsteochondral Defects — Autologous Chondrocyte Implantation (ACI)
Cartilage defects cause pain, swelling, mechanical symptoms; poor intrinsic healing. ACI: two-stage procedure — harvest cartilage → culture chondrocytes → reimplant under periosteal flap/biomatrix. Indications: symptomatic focal cartilage defects >2 cm² in young active patients. Alternatives: microfracture, OATS, osteochondral allograft. Complications: graft hypertrophy, delamination, failure.
Open topicOsteochondritis Dissecans (OCD)
Focal subchondral bone necrosis leading to cartilage instability. Common site: lateral aspect of medial femoral condyle. Clinical: pain, swelling, catching, locking in adolescents. Imaging: X-ray shows lucency; MRI defines stability of fragment. Treatment: stable juvenile lesions—activity modification; unstable/adult—drilling, fixation, grafting.
Open topicOsteogenesis Imperfecta — Sillence Types
OI due to COL1A1/2 defects; **Sillence I–IV** (classic) with expanded types V–VII; severity ranges from mild to perinatal lethal. Clinical: **blue sclerae**, dentinogenesis imperfecta, ligamentous laxity, short stature, recurrent fractures, hearing loss. Medical therapy: **bisphosphonates** (IV pamidronate/zoledronate) improve BMD and reduce fracture rate. Surgical: **intramedullary rodding** (telescopic Fassier–Duval) to correct deformity and reduce fractures. Multidisciplinary care: dental, au...
Open topicOsteoid Osteoma — Night Pain & RFA
Benign osteoblastic tumor
Open topicOsteolysis & Wear in Arthroplasty
Biologic response to wear particles (polyethylene > metal/cement) drives periprosthetic osteolysis via macrophage cytokine cascade. Risk factors: conventional PE, thin liners, malalignment, edge-loading, high activity, third-body wear. Radiology: progressive radiolucent lines, endosteal scalloping, cystic defects; CT helpful for pelvic osteolysis; metal artifact reduction MRI. Prevention: highly crosslinked PE (HXLPE), ceramic heads, proper component position, larger heads with caution for trunn...
Open topicOsteomalacia and Rickets
Defective mineralization: osteoid in adults (osteomalacia) vs physis in children (rickets). Etiologies: Vit D deficiency/resistance, phosphate deficiency (tumor‑induced, hereditary), renal tubular acidosis, CKD. Clinical: bone pain, proximal myopathy, waddling gait; in children—wrist/ankle widening, bowing, rachitic rosary, Harrison sulcus. Biochemical: Low Ca/PO4, High ALP, High PTH, Low 25‑OH Vit D (pattern varies in renal disease). Radiology: Looser’s zones; in rickets—widened physes with cup...
Open topicOsteomyelitis — Cierny–Mader Staging
Cierny–Mader classifies adult osteomyelitis by anatomic type (I–IV) and host status (A/B/C). Type I: Medullary; Type II: Superficial; Type III: Localized (cortical sequestration with stable bone); Type IV: Diffuse (circumferential). Host: A (healthy), B (systemic/local compromise), C (treatment worse than disease). Management tailored: debridement extent, stability, dead space management, local/systemic antibiotics. Principles: radical debridement, skeletal stability, soft-tissue cover, dead-spa...
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