Tru-Cut Biopsy (Core Needle Biopsy)

What Is It?

Needle Design

• The needle consists of two components:
  • Inner obturator (stylet) - has a specimen notch (trough/groove) near its tip
  • Outer cutting cannula - slides rapidly over the stylet to shear off the tissue in the notch
• Gauge: Typically 14-18G (14G most common for breast; 16G for liver; 18G for prostate and kidney)
• Sample notch: 15-30 mm long, yielding a core 15-20 mg or more in weight
• Available as manual (original) or spring-loaded/automated (biopsy gun - e.g., Bard Magnum®)

Mechanism of Action (Two-Step / Throw Technique)

1. Insert: The assembled needle is advanced to the edge of the lesion
2. Advance obturator: The inner stylet is quickly thrust forward - the specimen notch now lies within the target tissue, which prolapses into the notch
3. Fire cannula: The outer cutting cannula is rapidly advanced over the stylet, shearing off the tissue core trapped in the notch
4. Withdraw: The needle is removed with the tissue core inside the notch
5. The core is extracted and placed in formalin for histopathology

Indications

Advantages Over FNAC

Guidance Methods

• Ultrasound (US) guidance: Method of choice - real-time visualization, most accessible, 80-90% of breast lesions visible
• CT guidance: For deep lesions (retroperitoneal, pulmonary, hepatic); may use coaxial technique
• Stereotactic/DBT x-ray: For impalpable breast microcalcifications
• MRI guidance: For lesions visible only on MRI
• Blind (freehand): For palpable masses, synovial biopsy, or bedside procedures; higher sampling error

Pre-Procedure Preparation

• Informed consent (risks, benefits, alternatives)
• No fasting required for most superficial biopsies
• Loose-fitting clothing for access to biopsy site
• Check coagulation status (especially for liver/kidney)
• Sterile drape, povidone-iodine skin prep
• Local anesthesia infiltrated into skin and subcutaneous tissue (avoid infiltrating the target lesion itself)
• Patient positioned lying down (prevent vasovagal episodes)

Technique (Step-by-Step)

1. Position and prep the patient; apply local anesthetic
2. Make a small nick with a No. 11 blade scalpel (for easier needle passage)
3. Introduce the biopsy needle to the edge of the lesion under imaging guidance
4. Fire the needle (manual or automated)
5. Withdraw and retrieve the core into formalin
6. Take multiple passes (usually 3 cores) from different areas of the lesion
7. Apply pressure for 2-3 minutes post-procedure
8. Apply Band-Aid / sterile dressing

Needle Comparison Table (Liver Biopsy)

Complications

• Bleeding / hematoma at biopsy site - most common; apply pressure
• Bruising and soreness - usually resolves within a few days
• Infection / wound dehiscence - especially in immunosuppressed or steroid-using patients
• Non-diagnostic specimen - requires repeat biopsy
• Nerve injury - prolonged paresthesia if sensory nerve is nicked
• Muscle fibrosis/contracture - rare, after muscle biopsy
• Organ-specific complications:
  • Kidney: hematuria, perirenal hematoma, arteriovenous fistula, graft obstruction by blood clot
  • Liver: hemorrhage, bile leak, pneumothorax (subcostal approach)
  • Prostate: rectal bleeding, sepsis

Handling the Specimen

• Place cores immediately into 10% buffered formalin (do not allow to dry)
• For muscle biopsies: never place in fixative - process within 30 minutes (cryostat freezing required)
• Label clearly with site sampled
• Provide clinical summary, relevant investigations (EMG, lab values) to the pathologist

Special Variants

• Vacuum-Assisted Biopsy (VAB): Uses 7-11G needles with suction, yielding up to 300 mg per core - preferred for breast microcalcifications and B3 lesions; reduces sampling error
• EUS-guided Tru-Cut: For deep lesions (pancreas, mediastinum)
• Postmortem CT-guided biopsy: Used in forensic radiology for minimally invasive autopsy

• Bailey and Love's Short Practice of Surgery, 28th Edition
• Grainger & Allison's Diagnostic Radiology
• Yamada's Textbook of Gastroenterology, 7th Edition
• Pfenninger and Fowler's Procedures for Primary Care, 3rd Edition
• Smith and Tanagho's General Urology, 19th Edition
• Brogdon's Forensic Radiology
• Rheumatology, 2-Volume Set (Elsevier 2022)
• Sabiston Textbook of Surgery

Osteotome

Definition

Structure and Design

Osteotome vs. Chisel

Types of Osteotomes

1. By Shape

2. By Size

3. Named/Specialized Osteotomes

How It Works

• The blade can be twisted 90 degrees after partial penetration to crack (greenstick) the remaining cortex without displacing periosteum (used in Paley corticotomy)
• A broad osteotome is used with prying motions to peel cortical grafts from the iliac crest
• In rhinoplasty, the osteotome is inserted subperiosteally to preserve the periosteal sleeve and minimize swelling/bruising

Surgical Uses by Specialty

Orthopedic Surgery

• Osteotomy procedures (opening wedge, closing wedge, dome) - correcting bone deformities, realigning joints
• Corticotomy (Paley technique) for limb lengthening - a 5-mm osteotome cuts medial and lateral cortices; twisted 90° to crack posterior cortex while preserving endosteal/periosteal blood supply
• Bone graft harvesting from iliac crest - outline with osteotome or power saw, then peel with broad osteotome
• Pelvic osteotomies - triple innominate, Pemberton, Dega (curved osteotome used)
• Arthroplasty - preparing acetabulum, removing cement

ENT / Maxillofacial Surgery (Rhinoplasty)

• Medial osteotomies of nasal bones to fracture the nasal pyramid
• Lateral osteotomies along the nasofacial groove (using guarded osteotome)
• The osteotome is placed vertically in the plane of the nasal septum and carried to slightly above the dorsal hump, then angled at a beveled angle to undercut the nasal bones - this prevents the "rocker" phenomenon causing postoperative nasal widening
• Subperiosteal approach preferred to avoid periosteal laceration

Spinal Surgery

• Laminectomy - removing laminar bone, accessing the canal
• Vertebral body resection - in combination with Cobb elevator and rongeurs

Dental / Oral Surgery

• Sinus floor elevation (osteotome technique) - sequential expansion of alveolar bone; condensing bone for implant site preparation
• Alveolar ridge expansion for dental implants
• Tooth extraction - sectioning multi-rooted teeth

Corticotomy Technique (Paley) - Illustrated

• A: 1.5 cm skin incision with periosteal elevation
• B: Osteotome twisted transversely to cut groove in anterior cortex only
• C: Anterior groove cut to (but not through) medullary cavity
• D: Periosteum elevated laterally; lateral cortex cut with 5-mm osteotome
• E: Anteromedial periosteum elevated; medial cortex cut
• F: Osteotome twisted 90° in posteromedial cortex to crack it; repeated at posterolateral cortex
• G: Osteoclasis completed by gentle external rotation of fixator rings

Nasal Osteotomy - Illustrated

• (A) Osteotome placed in plane of nasal septum for medial osteotomy
• (B) Beveled cut at an angle to undercut nasal bones - opens the nasal root to a higher level
• (C) Resulting bone wedge showing the double beveled edge geometry

Comparison with Similar Instruments

Precautions and Complications

• Over-penetration - especially near neurovascular structures; use guarded osteotomes when needed
• Fracture propagation in unintended direction - improper alignment or angle
• Excessive heat - more relevant with power instruments; irrigate with saline
• Periosteal stripping - broad or excessive use can devascularize bone
• Instrument breakage - using a bent or fatigued osteotome under heavy mallet blows

Historical Note

• Campbell's Operative Orthopaedics, 15th Edition, 2026
• Cummings Otolaryngology Head and Neck Surgery
• Rockwood and Green's Fractures in Adults, 10th Edition, 2025
• PMC review on osteotomies: techniques and hardware (Azhideh et al., 2025)

Jaboulay's Procedure

Historical Note

What Is a Hydrocele?

Indications for Surgery

• Large or symptomatic hydrocele causing discomfort, dragging sensation, or cosmetic concern
• Thick-walled hydroceles (where Lord's plication is not feasible)
• Large hydroceles (Jaboulay's is specifically preferred over Lord's for large or thick-walled sacs)
• Failed aspiration or sclerotherapy
• Secondary hydrocele (once underlying cause is ruled out/treated)

Anatomy Relevant to the Procedure

• Parietal layer - outer, forms the hydrocele sac wall
• Visceral layer - inner, tightly adherent to the testis and epididymis

Surgical Technique - Step by Step

Position and Anesthesia

• Patient supine, legs slightly apart
• General, spinal, or local anesthesia (LA is feasible for non-obese patients)
• Scrotum prepped and draped

Step 1 - Incision

• A transverse or longitudinal scrotal incision (3-5 cm) is made over the most prominent part of the hydrocele
• Incision deepened through skin → dartos muscle → external spermatic fascia → cremasteric layer → internal spermatic fascia to expose the hydrocele sac (parietal tunica vaginalis)

Step 2 - Delivery of the Hydrocele

• The hydrocele is delivered through the wound by blunt and sharp dissection of surrounding fascial layers
• Care taken to avoid the vas deferens, testicular vessels, and epididymis

Step 3 - Aspiration / Opening the Sac

• The hydrocele fluid is aspirated with a needle and syringe (to decompress the sac and improve handling)
• The parietal tunica vaginalis is then opened widely with scissors
• The interior of the sac is inspected (look for secondary causes - tumour, infection, trauma)
• If a tumour is suspected, do not aspirate (risk of malignant seeding)

Step 4 - Partial Excision of the Sac

• The excess parietal tunica vaginalis is excised, leaving a 1-2 cm margin around the testis and epididymis
• Do NOT injure the epididymis, vas deferens, or testicular vessels
• Bleeding from the cut edge is controlled with overrunning (continuous) absorbable sutures or diathermy

Step 5 - Eversion (the Key Step)

• The remaining cut edges of the tunica vaginalis are everted (turned inside-out) around behind the testis and epididymis
• The everted edges are sutured together behind the spermatic cord with absorbable interrupted or continuous sutures
• This places the raw/secreting surface of the tunica facing outward into the retroperitoneal fatty tissue, where it cannot accumulate fluid
• The testis now sits in a newly created pouch in the scrotal fascial planes, outside the tunica

Step 6 - Haemostasis and Closure

• Meticulous haemostasis (critical - the most important step to avoid haematoma)
• A corrugated or closed suction drain may be placed in the scrotum, especially after extensive dissection
• The testis is replaced into the scrotum
• Wound closed in layers: dartos with absorbable sutures, skin with interrupted/subcuticular sutures
• Pressure dressing (scrotal support/jockstrap) applied

Illustration of the Procedure

Lord's procedure - plication sutures bunching the tunica:

Jaboulay's procedure - everted sac anchored behind the testis:

Mechanism of Cure

Comparison: Jaboulay vs Other Procedures

Postoperative Care

• Scrotal support (jockstrap) for 4-6 weeks - reduces swelling and supports wound healing
• Avoid strenuous activity and heavy lifting for 2-4 weeks
• Pain medication (NSAIDs) for 3-5 days
• Drain removed at 24-48 hours
• Sutures removed at 5-7 days (if non-absorbable)
• Regular wound inspection for haematoma/infection

Complications

Bailey and Love note: "Unless great care is taken to stop bleeding after excision of the wall, haemorrhage from the cut edge is liable to cause a large scrotal haematoma. Overrunning stitches at the cut edge can be used to reduce this risk."

Approach Selection

• Bailey and Love's Short Practice of Surgery, 28th Edition (primary textbook source)
• Fischer's Mastery of Surgery, 8th Edition
• Comparative analysis of Lord's plication and Jaboulay's eversion - Int Surgery Journal, 2026 (100 patients, prospective)
• Urology Textbook - Hydrocelectomy - Dirk Manski MD