Case 1
Petarda, beagle, female, 5 meses.
Premature closure distal epiphyses of the radius. ELDORCIEO CODO. Little Extremidad Deviation
Length difference between both anterior limbs: 15 mm
Straced Rotulas with Dcha and striated knee
needles 1.5-2.0 mm: external diameter thread 2.0 and 2.7 mm respectively
needles 2.5-3.0 mm: external diameter thread 3.5 and 4.1 mm respectively
needles 4.0 mm: external diameter thread 5.5 mm
Cylinders:
Needles 1.5-2.0 mm
Needles 2.5-3.0 mm
Needles 4.0 mm
Composition of the Straced Rotula Elongator
6.0mm Metric Step: Half from the right to the right and half from the thread to left. Each complete turn provides 2.0mm distraction.
Surgical technique
bone drilling (2.5 mm needle)
If the limb is not diverted we can place the elongator and perform the osteotomy at the end of the intervention.
We placed 4 ball joints on the distraction bar (it should not be cut initially as "burrs" form that prevent the ball joints from being screwed in): 2 on the right turning side and 2 on the left turning side. We drilled a hole in the distal fragment of the radius perpendicular to the bone and at the planned location (Fig. 5). If the needle with a thread at the tip has the same diameter as the screw pass-throughs (2.0-2.7-3.5), we can use them to create its thread in the bone (this ensures less osteolysis around the implants)..
For the placement of the needles, we can use the cylinders as drill guides, tap, and then introduce the needle retrogradely into the corresponding cylinder, insert it into the hole of the patella, and screw the needle into the bone. (See video). Finally, we proceed to the osteotomy of the ulna and radius. We will initiate elongation after a latency period (without distraction) of 3-5 days. Each day, the owner must turn the distraction bar HALF A TURN TO THE LEFT (equivalent to 1.0 mm). At its distal end, we screw on a grooved washer to facilitate the turning.
Final aspect of the patient with the elongator "in situ". It must be carefully planned that we have sufficient space in the proximal and distal distracting bar that allows us the elongation to be carried out. The proximal bar can be cut with a shear if it is excessively long and is stuck in the patient's skin. The distal part should not be cut since in case of doing so, it makes it difficult to insert the spelling washer. You should not exceed the level of the metacarpo-Falangian articulation
Weekly radiographs must be performed to verify that the distraction is effective
16-11-13 When both extremities have the same length we finish the distraction although we can continue a few more mm since the not affected limb will continue its growth. Many dogs about 15 kg tolerate discrepancy of 2 cm or more between both limbs without symptomatology
bone appearance on 9-12-13. Note the perfect joint congruence of the elbow. The carporadial articulation is ankylose but does not present pain