1. Short-term Hardware Outcomes Following Patellar Tendon Advancement in Pediatric Patients with Crouch Gait
Authors
Institutions

2. Introduction Cerebral Palsy: motor syndromes
- 2° to brain development
Crouch gait – spasticity/contracture
Hamstring/psoas tightness
Lever-arm dysfunction
Weakness
Impaired balance
Cerebral palsy (CP) is a diagnostic term used to describe a group of motor syndromes resulting from disorders of early brain development. CP is caused by a broad group of developmental, genetic, metabolic, ischemic, infectious, and other acquired etiologies that produce a common group of neurologic phenotypes.
CP is the most common and costly form of chronic motor disability that begins in childhood with a prevalence of 2/1000.
Kliegman, Robert M., Richard E. Behrman, Hal B. Jenson, and Bonita F. Stanton. Nelson Textbook of Pediatrics. Philadelphia: Saunders, 2007.

3. Crouch Gait Body Mechanics Knee and back pain Quadriceps insufficiency
Knee flexion
Hip flexion
Ankle dorsiflexion
Knee and back pain
Quadriceps insufficiency
Patella alta & Elongation of patellar tendon
2° to achilles tendon lengthening
The loss of an adequate plantar flexion/knee extension couple keeps the ground reaction force behind the knee joint and in front of the hip and ankle joint.
Fixed knee-flexion contractures often develop.
Patella alta and elongation of the patellar tendon develop over time and become contributing factors.
Knee pain, probably related to the increased quadriceps forces required to stabilize the flexed knee joint, increased patellofemoral compressive forces, and/or eventual patellar pole or tibial tubercle fracture, frequently develops as well.
Anterior subluxation can be associated with crouch gait.
Knee and back pain have been mentioned as two of the primary factors that limit or decrease the walking ability of these patients.
When present, quadriceps insufficiency and fixed knee-flexion contractures contribute to crouch gait.
Chambers Eur J Neur 2001
Stout et al. JBJS 2008

4. Treatment Gait analysis for evaluation (Pre-op Mov?) Conservative
Occupational/Physical therapy
Assistive devices
Medical
Muscle relaxants
Benzodiazepines
Botulinum toxin
Treatment for crouch gait generally involves a kinematic analysis of gait for quantitative assessment.
Conservative treatments include:
OT/PT: ADLS--- prevent contractures, strength conditioning, stretching, movement
Assistive Devices: walkers, poles, standing frames etc…
Medical therapies: (to treat spasticity)
-muscle relaxants – dantrolene orally, baclofen orally or intrathecal
-Benzos
-Botulinum Toxininjected into specific muscle groups
Kliegman, Robert M., Richard E. Behrman, Hal B. Jenson, and Bonita F. Stanton. Nelson Textbook of Pediatrics. Philadelphia: Saunders, 2007.

5. Surgical Treatment Procedures typically done (Get from Halanski)
(Preop and postop x-rays)
(Preop/postop gait analysis)
Possibly describe what procedures are typically done.
Patellar tendon advancement: Patellar tendon is excised from the tibial tuberosity. Transverse lumen is drilled through the patella and on the tibia distal to the tibial tuberosity. Cercalage wire/cable is passed through the patella and proximal tibia. Patellar tendon is transected with the leg in extension and the shortened tendon is reinserted onto the tibial tuberosity with suture.
Cercalage wire/cable is secured into place to provide mechanical support for the reinserted patellar tendon.

6. Crouch Gait Pre and post-op radiographs of a patient with crouch gait.
Treated with distal femoral osteotomy and patellar tendon advancement. (Get surgical report at butterworth)
Describe procedure

7. Surgical Treatment Distal femoral extension osteotomy
Patellar tendon advancement
Patellar insertion freed
Patellar tendon advanced distally along tibia
- Cercalage wire from patella to insertion
Stabilize new insertion
Combination
REITERATE THE OBJECTIVE:
To examine the short-term outcomes of hardware failure following patellar tendon advancement in patients with crouch gait using a cercalage wire versus a cercalage cable for patellar tendon stabilization.
Stout et al JBJS 2008

8. Objective
To examine the short-term outcomes of hardware failure following patellar tendon advancement in patients with crouch gait
2 Hardware types
- Cercalage cable
- Cercalage wire

9. Methods Retrospective cohort study radiographs Inclusion Criteria
Billing codes: patellar advancement
Helen DeVos Children’s Hospital
1/1/03 to 11/2/08
Exclusion criteria
Different procedure performed
Age > 17

10. Methods Patient radiographs Patient records Fisher’s exact test
Cercalage wire vs. cable
Failure vs. Intact
Patient records
Age at procedure
Time to post-op radiograph
Time to failure
Fisher’s exact test

11. Radiographs Cercalage wire Cercalage cable s/p surgery: wire vs. cable
-wire secured manually
-cable is clamped
Mention differences in surgery in pictures
– femoral extension osteotomy in the wire picture
- Reiterate only focusing on the patellar advancement portion of the procedure

12. Hardware Failure Wire Failure at 117 Days:
-notice that the patellar tendon is healed and that the patella is still advanced despite hardware failure
-requires a 2nd surgery to remove hardware secondary to discomfort

13. Results 16 Patients with 31 Patellar advancements
Fisher’s exact T-test (p < 0.001)
Hardware
Wire
Cable
Age (years) 13 10
# Performed 11 20
# Failed 9
Failure Rate
89% 0%
Avg. Time F/U
258 90
Overview of study numbers:
Wire Follow-up:
-258 days average until FAILURE
Cable Follow-up:
-90 day average TOTAL FOLLOW-UP
Need to wait until we can get the same average follow-up time for both groups.

14. Discussion Statistically significant advantage to cables
Shorter follow-up time
Continued observation cables
1 year follow-up

15. Conclusion Cables show better outcomes than wires
1 year follow-up for recommendations
Possible implications
Decrease failed hardware removal
More rapid mobilization post-op
Reference

16. Future Work Continue follow-up for > 1 year
Evaluation of long-term hardware outcomes
Evaluation of patellar advancement on growth plate mechanics
Evaluation of gait kinematics
Reference

17. Acknowledgments
Attending
Editor
Statistician
Institution