2. OUTLINE
• Patient brief history
• Approach to interlocking nail of tibia
• Length and working length
• Patient’s outcome
• References
3. Brief history
• 29 years old malay gentleman
• No known comorbids
• Alleged MVA, sustained closed comminuted
fracture midshaft of left tibia
• Planned surgery: Interlocking nail
5. Approach to interlocking nail of tibia
• Patient is placed on supine position
• Left lower limb is clean and drapped
• Figure of 4 position is used
• Skin incision is extended about 3cm proximal
to the tibial plateau at the anterior aspect of
the left knee
• Patella tendon is incised longitudinally in line
with the medullary cavity
6. ENTRY POINT
IN THE FRONTAL PLANE: IN LINE WITH THE MEDULLARY CANAL (3 MM MEDIAL OF THE TIBIAL CREST)
IN THE SAGITTAL PLANE: JUST DISTAL TO THE ANGLE BETWEEN TIBIAL PLATEAU AND ANTERIOR TIBIAL METAPHYSIS
7. • Solid curved awl is used to create an entry point for
nail
• Fracture is reduced and ball-tipped guide wire is
inserted
• Medullary cavity is reamed starting from smaller size
reamer. Medullary cavity should be reamed 1 size
larger than the intended nail
• Tissue protector is used during reaming procedure
• Daflon is inserted and straight guide wire is inserted to
replaced the ball-tipped guide wire
• Length of the nail is measured using radiographic ruler
• Nail of appropriate length and diameter is inserted
• Guide wire is removed and proximal and distal locking
screws are inserted
• Patella tendon is repaired , paratenon is sutured.
Subcutanous tissue and skin is closed
9. Length and working length
• Total nail length
• Length of nail-bone contact
– Larger the contact area, the higher the resistance
to motion
• Working length
10. Total nail length
• Too long a nail protruding at the insertion site
causes pain and limitation on motion
• Too short a nail compromises fixation
11. Length of nail bone contact
• Total surface area of contact between the nail
and bone
• Larger the contact, higher the resistance to
motion
13. • Reflects the nail carrying the major load of stress
across the fracture site
• Bending stiffness of a nail is inversely proportional to
square of its working length
• Torsional stiffness is inversely proportional to its
working length
• Conclusion: shorter working length means stronger
fixation
• 2 ways of modifying the working length:
1. Medullary reaming
2. Interlocking