INTERLOCKING NAIL OF TIBIA

PREPARED BY: DR. TAN YONG JIA

OUTLINE

• Patient brief history

• Approach to interlocking nail of tibia

• Length and working length

• Patient’s outcome

• References

Brief history

• 29 years old malay gentleman

• No known comorbids

• Alleged MVA, sustained closed comminuted fracture midshaft of left tibia

• Planned surgery: Interlocking nail

Pre-op x-rays

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

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

ENTRY POINT

• 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

CHECK X-RAYS

Length and working length

• Total nail length

• Length of nail-bone contact

– Larger the contact area, the higher the resistance to motion

• Working length

Total nail length

• Too long a nail protruding at the insertion site causes pain and limitation on motion

• Too short a nail compromises fixation

Length of nail bone contact

• Total surface area of contact between the nail and bone

• Larger the contact, higher the resistance to motion

Working length

• 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 reaming2. Interlocking

NAILS AVAILABLE IN OT

4.5CM

5CM

7.5CM

4CM

4CM

5CM

XOA ON TCA 6 WEEKS

REFERENCES

• AO Trauma surgery reference

• The elements of fracture fixation, Anand J. Thakur

THANK YOU