Email kcmidway@tampabay.rr.com

Mission Statement:
To provide quality referral orthopedic and soft tissue surgical services to patients at a reasonable cost to clients in Citrus County Florida and surrounding counties, as well as an alternative referral site for their veterinarians.

Pre-Op -1

Click x-rays to see larger

Pre Op - 2

Post Op - 1

Post Op - 2

8 Week Out - 1

8 Weeks Out - 2

Dr. Nayfield's Screw Pin

Interested Veterinarians Please order
by Screw Pins by calling
352-422-7858
Each pin is $40.

The Screw Pin....

A means of combining bone plating with external fixation to provide economical fracture repair in certain applications.

The Theory…….

Application of a typical dynamic compression bone plate involves placing that plate on the “tension” side of the fracture. Many times when there is comminution the plate is used in a “buttress” fashion and provides the necessary support to allow fracture healing. In some fractures there may be comminution or bone fragments on the compression side. Under these conditions:

  • Application of the plate would be inadequate since the lack of bone to bone support on the compression side would allow the plate to cycle and most likely fail.
  • Many times it is impractical and difficult to expose these fragments to incorporate them into a rigid fracture fixation.
  • Many times these fragments are so small that they cannot be incorporated into a rigid fixation.
  • With biological healing it is often beneficial to not disrupt the blood clots around the fragments.
  • It is often difficult to anatomically align the fracture pieces when dealing with comminution on the tension side of the fracture since the ends of the bones cannot be put back together like a jig saw puzzle.

The Facts……………………

Screw pins 002.JPG

  • The screw pin fits nicely into the chuck of regular rechargeable drills.
  • It is best to predrill the hole with a 2.7 or 3.2 mm drill bit.
  • The screw thread is self taping.
  • The pins fit the IMEX external fixator clamps and not the old style or Securos type.
  • The thread diameter is 4.0 mm and is too large for use in the 6.0 mm interlocking nail system.

Applications………………….

Distal Tibia Fracture with Comminution on the Lateral Side.

Tib Fib Fx.JPG

Bone plates for tibial fractures are typically placed on the medial surface. When comminution exists on the lateral side and the fracture is distal there may not be enough room to place an external fixation pin distally. The screw pin can be very easily placed in the most distal plate hole allowing  the external fixator to be applied to the outside of the leg giving a lateral buttress effect.

Distal Humeral Fracture With Comminution on the Lateral Side.

TPLO with Fib Fx.JPG

The bone plate may be placed on either the medial or lateral surface of the humerus. The advantages of placing the plate on the medial surface include less plate bending since the surface is flatter and not having to work around the radial nerve during exposure.  The screw pin allows stabilization with the plate to the bone as well as the lateral buttress with the external fixation device.

Fractures of the Fibula When Doing the TPLO Procedure.

Ulna Radial Fx.JPG

Occasionally dogs with chronic cranial cruciate ligament disease will develop severe arthritis resulting in a fusion of the fibular head to the tibia. Thus when the surgeon tries to rotate the osteotomy fragment to the proper position the fibula may fracture. The screw pin is inserted in the number one hole and a positive profile pin is inserted into the distal jig hole for the external fixator. The dangers in using the proximal jig hole for a pin is that often times this hole is very close to the joint and if not parallel to the joint surface could place the pin directly into the joint.

Ulna and Radius Fractures With Comminution on the Caudal Surface.

Bone plates are very useful in treating ulna – radius fractures. The extensor muscles and tendons flow over the plate very nicely. Although not an ideal circumstance the screw pins can be placed in the most proximal and most distal holes. The extensor muscles and tendons will still move freely over the screw heads but there may be some interference with the flexor muscles and tendons. Care can be taken to minimize these effects.


Application of the Screw
Pins to a Severely
Comminuted Midshaft
Tibia Fracture

Step 1: Apply the lengthening plate to each end of the fractures bones with screws in the holes next to the end holes.

Screw pins 031.JPG

Step 2: Insert screw pins in the proximal and distal end holes. Connect ex fix with two clamps in the center of the rod.

Screw pins 003.JPG

Step 3: Using the aiming device pre-drill the hole for the next screw pin. Repeat for the other screw pin.

Screw pins 010.JPG

Step 4: Apply the other screw pin using aiming device and apply clamps. Fill in any screw holes that will take a screw either single or double cortex.

Screw pins 015.JPG

Dr. Nayfield's Screw Pin

Interested Veterinarians Please order
by Screw Pins by calling
352-422-7858
Each pin is $40.