An inverted tendon reflex refers to the elicitation of the movement opposite to that normally seen when the reflex is elicited. Mechanism of Inverted Reflexes A lesion which simultaneously affects: This leads to 2 components: Mechanisms of hyperactive response: Types of Inverted Reflexes 1. Inverted supinator reflex: 2. Paradoxical triceps…
Tag: Orthopedics
Section Editor: Dr. Sulabh Kumar Shrestha, MBBS, PGY1 Orthopedics
Clinical Skills and Approaches 
Hoffmann’s Sign
History Method of Eliciting Hoffmann’s Reflex Mechanism of Positive Hoffmann’s Reflex Sudden stretch of the finger flexors causes involuntary finger flexor contraction due to activation of a monosynaptic stretch reflex. Exaggeration of the reflex is caused by hyperreflexia in the setting of upper motor neuron dysfunction. Upper motor neuron lesions…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Staging and Grading of Bone Tumors (Neoplasm)
Enneking (MSTS) Staging for Malignant Bone Tumors Stage Grade Site Metastasis IA Low Intra-compartmental None IB Low Extra-compartmental None IIA High Intra-compartmental None IIB High Extra-compartmental None III Any Any Regional or Distant Low-grade tumors generally have few mitotic figures, little if any cellular atypia, and have a relatively non-infiltrative…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Posterolateral corner (PLC) of knee
Anatomy of PLC 3 major static stabilizers of PLC Lateral collateral ligament Popliteus tendon Popliteofibular ligament Other static stabilizers of PLC Lateral capsule thickening Arcuate ligament Fabellofibular ligament Dynamic stabilizers of PLC Biceps femoris Popliteus muscle Iliotibial band (ITB) Lateral head of gastrocnemius There are 2 “Y” shaped structures in…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Osteogenesis Imperfecta : Mnemonic
Synonym: Brittle Bone Disease Incidence: 1 in 20,000 Gene defect: Col1A1 (17q) and Col1A2 (7q) Mnemonic: Remember “one” for “bone”. Collagen one is the main composition of bone. OI is a disorder of bone. Hence, the defect is is in Col1. Features Mnemonic: BLOOD Sillence Type Inheritance Features Mnemonic Collagen…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Stress, Strain, Viscoelastic behavior
Stress or load: Force over area (has units of Newton per square metre) Strain or deformation: Change in length over original length caused by applied stress or load (unitless and expressed as ratio or percentage) Mnemonic: If your boss is under a lot of stress, his personality changes (strain) A….
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Motor March Phenomenon
Motor march phenomenon is a sign of reinnervation like Hoffman-Tinel’s sign which has been discussed earlier. Observed in: Axonotmesis Repaired Neurotmesis Not observed in: Neuropraxia Motor march phenomenon: As the re-innervation of injured nerve proceeds, the muscles nearest to the site of injury recovers first followed by distal ones sequentially…
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…