Ch. 63: Tibia & Fibula Fx

Question 1

Welsh VSURG 2023

Biomechanical comparison of one pin versus two pin fixation in a canine tibial tuberosity avulsion fracture (TTAF) model

conclusion

Answer 1

In an ex vivo cadaveric TTAF model, vertically aligned two-pin fixation offers greater strength and stiffness when compared to a single-pin fixation.

Question 2

Miller JAVMA 2022

Good clinical outcomes achieved in young dogs with tibial tuberosity avulsion fracture repairs when implants were left in situ past skeletal maturity

• diff in outcome leaving or removing implants?
• client satisfaction?
• conclusion

Answer 2

There was no difference in long-term outcomes when compared with results of historical reports in which implants were removed 4 to 6 weeks postoperatively.

Client satisfaction was high, with 93% (38/41) grading outcomes as excellent and 95% (39/41) stating they would have surgery performed again in retrospect

Dogs with TTAF repairs may not need implant removal unless it becomes clinically necessary.

Question 3

Arun VCOT 2022

Factors contributing to the need for non-elective explant following surgical repair of tibial tuberosity avulsion fracture

• % non-elective vs. elective explant?
• major factors that influenced explant?

Answer 3

Non-elective explants in 20/64 (~30%); elective explants in 2/64 (~3%)

• Neutered dogs 19X more likely to require explant than intact
• Every 0.25mm increase in average pin size made it 2.5X more likely that an explant was required
• 14/20 had implant migration (70%) and this was the most common reason for explant

Question 4

Longo Vet Sx 2020

A three-dimensional computed tomographic volume rendering methodology to measure the tibial torsion angle in dogs

conclusion

Answer 4

The 3D volume rendering and axial CT techniques were precise and accurate for measuring TTa in dogs unaffected by patellar luxation. No difference was found between axial and 3D CT techniques.

Question 5

Neal VCOT 2020
Evaluation of a fixed-angle wedge osteotomy guide

• mean wedge angles b/w groups?
• conclusion

Answer 5

The mean wedge angles of the standard template and wedge osteotomy guide groups were 28.16 and 28.4 degrees respectively

Use of a fixed-angle surgical wedge guide was successful in consistently producing accurate closing wedge ostectomies regardless of surgeon experience

Question 6

Von Pfeil VCOT 2020

Tibial apophyseal percutaneous pinning in skeletally immature dogs: 25 cases (2016-2019)

• major complications?
• seroma? desmitis?
• explant?
• TPA change?
• long-term outcome?

Answer 6

No major complications occurred among the 19 smooth pin (SP) and 6 NTP (neg threaded pin)

Seromas and patellar desmitis rates were higher with SP (58%; 84%) versus NTP (0%; 33%)

Explantation was needed in 5/19 (26%) SP and 0/6 NTP cases

The mean tibial plateau angle (TPA) changed significantly between initial (25.6 degrees) and follow-up (18.8 degrees) radiographs

Long-term outcome, obtained at a mean of 19.9 months, was excellent in all cases

Question 7

Miraldo VCOT 2020

Feline distal tibial physeal fracture repair using a modified cross-pin technique with four pins

• healing?
• # needing explant?
• other complications?
• outcome?

Answer 7

Uncomplicated fracture healing occurred in all patients.

Two patients required implant removal due to K-wire migration and protrusion through the skin at 5 and 12 months post-surgery.

No other complications were noticed.

Eight patients had an excellent outcome, and one patient had a good outcome

Question 8

Hottman VCOT 2020

Biomechanical comparison of 2 locking plate constructs for the stabilization of feline tibial fractures

• plates used?
• stiffness?
• yield load and failure?

Answer 8

LCP – locking compression plate 2.7 mm ; OR CCP (conical coupling plate) 2.5 mm (Fixin’)

The LCP constructs were significantly stiffer than the CCP constructs when subjected to non-destructive bending and axial loading.

Yield load and failure load were significantly greater for LCP constructs compared with CCP constructs

Question 9

MacArthur VCOT 2020

Biomechanical comparison of two conical coupling plate constructs for cat tibial fracture stabilization

• plates used?
• stiffness?
• yield load and failure?

Answer 9

• standard, 6-hole, 2.5-mm CCP
• 6-hole, 2.5-mm prototype CCP (pCCP)

pCCP constructs were significantly stiffer than the CCP constructs in both modes of bending and axial loading.

Yield load and failure load were significantly greater for the pCCP constructs

Question 10

Verpaalen VCOT 2021

Biomechanical comparison of three stabilization methods for tibial tuberosity fractures in dogs: a cadaveric study

• 3 methods?
• which greatest stiffness?
• failure method?

Answer 10

PTBW and HESF significantly greater stiffness and had greater loads at 3 mm of axial displacement compared with K-wires alone

No difference between PTBW and HESF

Failure occurred by bending and pullout of the Kirschner wires for all fixation groups

Question 11

Zide VCOT 2020

A cadaveric evaluation of pin and tension band configuration strength for tibial tuberosity osteotomy fixation

• alignment and construct strength?
• conclusion

Answer 11

The use of vertically aligned pins versus horizontally aligned pins does not affect construct strength. These results support the placement of pins in a vertically or horizontally aligned fashion.

When performing a tibial tuberosity osteotomy, the addition of a TB adds significant strength to the construct