Linea aspera is a ridge of roughened surface on the posterior surface of the shaft of femur which serves as a site for attachment of muscles and intermuscular septum. The various structures attached to linea aspera can be remembered using few mnemonics: Mnemonic 1#: 1, 2, 3 It gives attachment…
Tag: Musculoskeletal system
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Perkin’s Timetable for Fracture Healing
One needs to understand the difference between bone union and consolidation first Union Consolidation Definition Partial/Incomplete repair Full/Complete repair Callus Calcified Ossified Attempted angulation Painful Painless Fracture line in X-ray Still visible Obliterated and crossed by bony trabeculae Full weight bearing Cannot be undertaken Can be undertaken Reference: Physiotherapy in…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
AO fracture classification made easy
It is an alpha-numeric system of classification developed by Muller and colleagues. Step 1: 1st digit specifies bone Step 2: 2nd digit specifies segment of bone Square definition: Proximal and distal segments are defined by a square whose sides = length of widest part of epiphysis Exceptions of square definition:…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Osteochondroma : Mnemonics
Features of Osteochondroma Mnemonic: Six “C” Commonest benign bone tumor Continue to grow until Closure of physis Cartilage cap (appears larger clinically than in X-ray) Continuous with native bone (cortex and medullary canal) Cane (pedunculated/stalked points away from joint and sessile/broad based have higher risk of malignant degeneration) Change (mutation)…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Rheumatoid hand
Ulnar drift or deviation of fingers Normal anatomical factors contributing to ulnar drift of fingers at MCP joint: Normal mechanical advantage of ulnar intrinsic muscles Asymmetry and ulnar slope of metacarpal heads of index and middle fingers Greater ulnar deviation permitted by radial collateral ligament when MCP joint is flexed…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Compartments, Muscles and Fasciotomy of the leg
Muscle Origin Insertion Action Innervation Anterior compartment 1. Tibialis anterior (TA) Superior 2/3 lateral surface of tibia Medial cuneiform, 1st metatarsal Dorsiflexion, foot inversion Deep peroneal nerve (L5) 2. Extensor digitorum longus (EDL) Superior 2/3 of fibula and interosseous membrane Middle and distal phalanx, lateral 4 toes Dorsiflexion, toe extension…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Arthrodesis Positions
Arthrodesis is the surgical fusion of a diseased joint for the purposes of obtaining pain relief and stability. The bones are fused in a position permitting most useful function but lose their natural motion. Shoulder Flexion: 30° Abduction: 20° Internal rotation: 40° Elbow One side: 90° Both side: One in…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Paget’s Disease of bone : Mnemonic
Synonyms: Osteitis deformans Collage of matrix madness Mnemonic: Sixteen “P”s 1. Paramyxovirus infection and inclusions in osteocalsts 2. Pain (most common symptom – localized fractures or nerve compressions) 3. Pelvis (most common site) 4. Polyostotic (more common; 85%) 5. Phases: Active (lytic, mixed, sclerotic) and Inactive 6. Plasma volume expansion…