Write a short note on congenital idiopathic sclerosis for Ms orthopedics theory examination
Reading File
Finding Sources
Finding Sources
Finding Sources
Reading File
Reading File
Reading File
Reading File
Reading File
Reading File
Reading File
Reading File
Reading File
Searching Images
congenital scoliosis hemivertebra classification radiograph
I have all the content I need. Here is the complete exam-ready short note:
Short Note: Congenital and Idiopathic Scoliosis
(For MS Orthopaedics Theory)
Definition
Scoliosis is a lateral curvature of the spine greater than 10 degrees (Cobb angle). It is broadly classified as congenital or idiopathic, and together these two types account for the majority of all scoliosis presentations (idiopathic alone accounts for ~70%).
Part I: Congenital Scoliosis
Definition
A three-dimensional spinal curvature caused by vertebral anomalies resulting in an imbalance of longitudinal spinal growth. A vertebral anomaly must be radiographically visible to make this diagnosis.
Prevalence
~1 in 1000 live births.
Embryology
The critical embryological period is the 5th to 8th weeks of gestation, when vertebral segmentation and formation occur.
Classification (Winter-Moe-Eilers / MacEwen modification)
| Type | Examples |
|---|---|
| Failure of Formation | Partial (wedge vertebra); Complete (hemivertebra) |
| Failure of Segmentation | Unilateral (unilateral unsegmented bar); Bilateral (block vertebra) |
| Mixed | Combination of both |
Natural History and Progression Risk (worst to best)
- Unilateral unsegmented bar + contralateral hemivertebra - most severe; mean progression 6-7°/year; most exceed 50° by age 2 years
- Unilateral unsegmented bar (most common congenital anomaly) - ~5°/year; reaches 50° by age 10
- Double convex hemivertebrae - 3-4°/year
- Single fully segmented hemivertebra - slowest; 1-2°/year
- Block vertebra - best prognosis; least severe
Progression is fastest in the first 5 years of life and during the adolescent growth spurt (10-15 years).
Associated Anomalies
- Neural axis abnormalities (diastematomyelia, tethered cord): up to 35-43% - MRI is mandatory
- Congenital heart disease: 25-54% - echocardiogram required preoperatively
- Genitourinary anomalies: 20-40% - renal ultrasound for screening
- Other musculoskeletal anomalies: Klippel-Feil syndrome, Sprengel deformity, clubfoot
Clinical Evaluation
- Examine skin of back for hair tufts, lipomas, dimples (suggest underlying dysraphism)
- Full neurological examination (clubfoot, calf atrophy, asymmetric lower limb - signs of cord involvement)
- Imaging: X-ray AP + lateral; MRI for intraspinal anomalies; echocardiography; renal ultrasound
Treatment
Nonoperative:
- Observation with radiographs every 6 months during rapid growth phases (0-5 yrs, 10-15 yrs)
- Bracing: generally ineffective for the primary curve but can control secondary compensatory curves
- Serial derotational casting: useful time-buying strategy to delay surgery
Operative (required in ~75% of patients):
| Procedure | Indication |
|---|---|
| In situ posterior spinal fusion | Small progressive curves; early intervention |
| Combined anterior + posterior fusion | Young patients - to prevent crankshaft phenomenon |
| Convex hemiepiphysiodesis | Small curves with growth potential |
| Growth-friendly techniques (growing rods, VEPTR, Shilla) | Young patients (<8-10 yrs) with large progressive curves |
| Hemivertebra resection | Isolated hemivertebra; combined with A+P arthrodesis |
| Vertebral column resection / osteotomy | Severe rigid deformity |
Note: Congenital scoliosis is the condition in which paraplegia occurs most often after instrumentation. Intraoperative spinal cord monitoring (SSEP + MEP) is mandatory.
Part II: Idiopathic Scoliosis
Definition
Scoliosis of unknown cause; accounts for 70% of all presentations. Likely multifactorial in origin.
Classification by Age of Onset
| Type | Age | Key Features |
|---|---|---|
| Infantile | < 4 years | Left thoracic curve; more common in boys; plagiocephaly; ~90% resolve spontaneously; use Mehta RVAD to predict progression |
| Juvenile | 4-10 years | Right thoracic curve; 25% have spinal cord abnormality; 95% risk of progression; less responsive to bracing than adolescent type |
| Adolescent (AIS) | > 10 years | Most common; right thoracic; female predominance; associated with near-normal life expectancy |
Distinction between early onset (<8 yrs) and late onset (>8 yrs) is important because alveolar development ceases at age 8 - severe early-onset curves can lead to cor pulmonale and premature death.
Adolescent Idiopathic Scoliosis (AIS) - Key Points
- Prevalence: Cobb >10° in 0.5-3% of population; Cobb >30° in 1.5-3 per 1000
- Risk factors for progression: Female sex, remaining skeletal growth, thoracic location, larger initial curve magnitude
- Risser sign: Used to assess skeletal maturity and guide treatment
- Long-term studies show 68% experienced curve progression; thoracic curves of 50-75° progress at ~1°/year even after maturity
Infantile Idiopathic Scoliosis - Mehta Classification
- RVAD (Rib-Vertebra Angle Difference): measured between apical vertebra and its ribs
- Phase I (no rib overlap): RVAD <20° = 80% chance of resolution; RVAD >20° = 80% chance of progression
- Phase II (rib overlaps apical vertebra) = very high risk of progression
Treatment of Idiopathic Scoliosis
| Curve | Management |
|---|---|
| < 25° | Observation; clinical + radiographic follow-up |
| 20-45° (growing child) | Bracing (prevents progression; does not correct curve) - e.g., TLSO, Milwaukee brace |
| > 45° | Bracing ineffective |
| > 40° with progression, truncal imbalance, or unacceptable cosmesis | Surgery |
Surgical treatment:
- Corrective instrumentation and posterior spinal fusion
- Intraoperative monitoring: SSEP, MEP, free-run and stimulated EMG
- Risk of neurological injury: 0.4% (1 in 250)
- For young children with large curves: growing rods, VEPTR, magnetically controlled growing rods - followed by definitive fusion after age 10
Summary Comparison Table
| Feature | Congenital | Idiopathic |
|---|---|---|
| Cause | Vertebral anomaly (visible on X-ray) | Unknown, multifactorial |
| Key investigation | MRI (neural/intraspinal anomalies) | Clinical + X-ray; MRI if juvenile/infantile |
| Associated anomalies | Cardiac, renal, neural axis | Usually none |
| Bracing | Limited; for compensatory curves only | Effective for 20-45° in growing child |
| Surgery rate | ~75% | Indicated at >40° with progression |
| Most severe type | Unilateral bar + contralateral hemivertebra | Juvenile type (95% progression) |
Sources: Campbell's Operative Orthopaedics 15th Ed 2026; Miller's Review of Orthopaedics 9th Ed; Bailey and Love's Short Practice of Surgery 28th Ed
Write a short note on microdiscectomy for Ms orthopedics theory examination
Finding Sources
Finding Sources
Reading File
Finding Sources
Reading File
Finding Sources
Reading File
Finding Sources
Reading File
Finding Sources
Finding Sources
Finding Sources
Finding Sources
Finding Sources
Reading File
I now have comprehensive, detailed content from Campbell's Operative Orthopaedics to write an excellent exam-ready short note on microdiscectomy. Here it is:
Short Note: Microdiscectomy
(For MS Orthopaedics Theory)
Definition
Microdiscectomy (microscopic lumbar disc excision) is a minimally invasive surgical procedure for the removal of a herniated lumbar intervertebral disc using an operating microscope and microsurgical instruments through a small paramedian incision. It has replaced standard open laminectomy as the procedure of choice for herniated lumbar disc.
Indications
Absolute indications:
- Cauda equina syndrome (bowel/bladder dysfunction with bilateral neurological deficit) - surgical emergency
- Progressive neurological deficit despite conservative management
Relative/elective indications:
- Radicular pain (sciatica) with or without neurological deficit that has failed 6 weeks of conservative management
- Neurological deficit (motor weakness or sensory loss) corresponding to the level of disc herniation
- Positive straight-leg raise (SLR) test with radiological confirmation (MRI) of disc herniation matching the clinical level
- Unacceptable disability or failure to return to work despite adequate conservative treatment
Prerequisites Before Surgery
- Correlation of clinical signs with imaging (MRI is gold standard)
- Level of herniation confirmed radiographically; MRI is essential
- Conservative treatment failure: analgesics, physiotherapy, epidural steroid injections
Surgical Setup and Patient Positioning
- Anaesthesia: General endotracheal anaesthesia (local anaesthesia also possible)
- Position: Prone in knee-chest (modified kneeling) position on a specialised frame (e.g., Andrews table)
- Advantages of knee-chest position:
- Abdomen hangs free - minimises epidural venous distension and intraoperative bleeding
- Ligamentum flavum is placed under slight tension - easier removal and greater canal access
- Maximises lumbar kyphosis - opens interlaminar space
- Equipment: Operating microscope (400-mm lens), small-angled Kerrison rongeurs, microinstruments, suction/nerve root retractor, McCulloch or tubular retractor system
- Level confirmation: Lateral radiograph or intraoperative fluoroscopy - mandatory before incision
Surgical Technique (Microscopic Lumbar Discectomy)
The technique is performed via the McCulloch retractor approach or the tubular retractor approach. Both follow the same key steps:
1. Skin incision
- ~25-30 mm (1-inch) paramedian incision from midspinous process of upper vertebra to the superior margin of the lower vertebral spinous process
- Meticulous haemostasis with electrocautery
2. Fascial incision and muscle retraction
- Incise lumbodorsal fascia at midline
- Subperiosteal dissection of paraspinal muscles to expose the interlaminar space
- Insert McCulloch self-retaining retractor or sequentially dilate with tubular dilators
3. Level confirmation
- Fluoroscopy or radiograph with metallic marker to confirm correct level
4. Entering the epidural space
- Identify the critical angle - junction of the caudal lamina leading edge and medial edge of the superior articular process
- Pedicle lies just lateral to the critical angle
- Traversing nerve root is just medial to the pedicle
- Target disc is just cephalad to the critical angle and pedicle
- Elevate and excise the superficial leaf of ligamentum flavum with Kerrison rongeurs
- High-speed drill used if bone removal is needed (partial inferior laminotomy)
5. Neural decompression
- Identify traversing nerve root under microscope
- Gently retract the nerve root medially with suction/nerve root retractor
- Bipolar electrocautery to control epidural bleeding; avoid monopolar near neural structures
- Identify herniated disc fragment - pituitary rongeur instruments marked at maximum allowable depth to prevent great vessel/visceral injury
6. Disc fragment removal
- Dilate the annular defect
- Remove extruded/herniated nucleus pulposus with pituitary rongeurs
- Explore lateral recess and foramen for free fragments
- Do not aggressively curettage the disc space - increases risk of recurrence and endplate damage
- Adequacy of decompression confirmed by free movement of nerve root - not by amount of disc material removed
7. Closure
- Bipolar haemostasis of epidural veins
- Fascia closed with absorbable sutures (McCulloch); tubular retractor approach - fascia self-seals
- Skin closure with absorbable subcuticular sutures or skin glue
Tubular/Minimally Invasive Variant
- Same principles as standard microdiscectomy but uses a tubular retractor (14-24 mm diameter) in a transmuscular, muscle-splitting approach
- Avoids detachment of lumbodorsal fascia from supraspinous ligament
- Guidewire placed under fluoroscopy; sequential dilation of paraspinal muscles
- Advantages: less soft-tissue damage, shorter hospital stay, faster return to activity
- Disadvantage: no proven superior clinical outcomes over standard microdiscectomy
Endoscopic Alternative
- Transforaminal or interlaminar endoscopic discectomy allows access from L1-S1 without significant bone resection
- Does not violate the zygapophyseal joint - minimises iatrogenic instability
- Lower postoperative CRP and IL-6 levels (less inflammatory response) vs. standard microdiscectomy
- Can be performed under monitored anaesthesia care (no general anaesthesia needed)
Postoperative Care
- Procedure is done on an outpatient basis (same-day surgery)
- Bupivacaine with epinephrine injected into paraspinal muscles at start and end of procedure - aids early mobilisation
- Patient may shower the day of surgery (skin glue closure)
- Activity permitted as tolerated once skin healed
- No routine brace required
Results and Outcomes
- >90% good-to-excellent results in properly selected patients (dominant radicular pain with confirmed disc herniation)
- Relief of sciatica/radicular pain is the primary outcome; axial back pain relief is less predictable
- Return to work: typically 2-4 weeks for sedentary work; 4-8 weeks for heavy labour
- Neurological recovery: motor deficits recover slowly over months even after adequate decompression
Complications
| Complication | Notes |
|---|---|
| Dural tear / CSF leak | Most common intraoperative complication; primary repair with absorbable suture if identified; risk increases with revision surgery |
| Nerve root injury | Excessive retraction or thermal injury; avoid monopolar cautery near nerve root |
| Recurrent disc herniation | ~5-15%; same or adjacent level |
| Discitis / infection | 0.1-0.5%; prophylactic antibiotics given pre-operatively |
| Wrong level surgery | Prevented by mandatory intraoperative fluoroscopy / X-ray |
| Vascular injury | Anterior vessels (aorta, IVC, iliac) injured by overly deep pituitary rongeur - mark instruments to maximum safe depth |
| Epidural haematoma | Rare; presents with acute neurological deterioration postoperatively - requires urgent evacuation |
| Failed back surgery syndrome | Back pain persisting or worsening after surgery, especially if patient selection was poor |
| Cauda equina syndrome | Very rare late complication from haematoma or recurrent disc |
Advantages Over Open Laminectomy/Discectomy
| Feature | Microdiscectomy | Open Laminectomy |
|---|---|---|
| Incision | ~25 mm | ~80-100 mm |
| Muscle dissection | Minimal | Extensive |
| Blood loss | Less | More |
| Hospital stay | Day case | 3-5 days |
| Postoperative pain | Less | More |
| Bone removal | Minimal | Extensive |
| Complications | Same or less | Comparable |
| Outcome | Equivalent | Equivalent |
Key Points for Exam
- Microdiscectomy has replaced standard open discectomy as the gold standard for surgical treatment of lumbar disc herniation
- The critical angle is the key landmark - defines the position of pedicle, traversing nerve root, and disc
- Knee-chest position is preferred - reduces epidural venous bleeding by allowing abdomen to hang free
- Absolute indication is cauda equina syndrome (emergency)
- Instruments must be marked at maximum allowable depth to prevent anterior vascular injury
- Fluoroscopic level confirmation is mandatory intraoperatively
- Outcome depends on correct patient selection - dominant leg pain > back pain with correlating MRI findings gives best results
Source: Campbell's Operative Orthopaedics 15th Ed 2026, Technique 46.4 - Microscopic Lumbar Discectomy
This is a shared conversation. Sign in to Orris to start your own chat.