Clinical Trial: Outcomes of the Evans Calcaneal Lengthening Based on Bone Grafting Material

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Observational

Official Title: Outcomes of the Evans Calcaneal Lengthening Based on Bone Grafting Material

Brief Summary: The Evans calcaneal lengthening is a common surgical correction used for children with spastic cerebral palsy (CP) and painful flat feet. This procedure involves the insertion of a trapezoidal bone graft into the calcaneus bone. Both autograft and allografting materials have been used for this procedure, but both types of grafting materials have associated limitations. Autologous grafting materials, which are harvested from the iliac crest at the time of surgery, are associated with high rates of prolonged donor site pain. There is limited bone available from the iliac crest. For this reason autologous bone grafts are not commonly used for the Evan's procedure. Cadaver allografting materials are variable in their mechanical and geometric properties. Recently, xenografting materials have been developed that have consistent mechanical properties and are available in a larger size that is formed to fit the individual patient intraoperatively. The purpose of this study is to evaluate the long term outcomes of the procedure with the different graft options. Another purpose is to compare the difference in surgical correction obtained with the cadaver allograft and the xenografting materials. This study will also observe and evaluate a wide range of outcome variables that encompass multiple levels of patient care, from clinical observation to parent and patient satisfaction, and compare these with the observed changes in the radiographic and plantar pressure parameters of the foot. This data will be evaluated pre to post surgery and for two years of follow-up time. The aim is to uncover the characteristics of collapse observed with the two different grafting materials.

Detailed Summary:

Primary Outcome Measures:

  1. Measurement on radiographs of distance between heme clips located in calcaneous bone of the foot. Within the patient's own calcaneous bone, a heme clip will be placed on each side of the osteotomy. From radiographs, the amount of collapse will be determined by measuring the distance from one heme clip to the other. Changes in the distance between the clips indicate collapse of the graft.

  2. Radiographic measurements of weight bearing feet of the bovine xenograft group and iliac crest allograft group (tricortical and bicortical), pre-operatively and post-operatively.

    1. Lateral Radiographs: Talocalcaneal angle, Talo first metatarsal angle, Talo horizontal angle, and Calcaneal pitch
    2. Anterior-Posterior Radiographs: Talocalcaneal angle, Talo first metatarsal angle, and Talonavicular coverage
  3. Comparison of ligamentous laxity between the two grafting material groups, as measured by the Beighton measurements at patient's pre-operative orthopaedic clinical appointment.

Secondary Outcome Measures:

1. Plantar pressures values of interest are of six segments: medial heel, lateral heel, medial midfoot, lateral midfoot, first metatarsal and second metatarsal. The center of pressure index, total contact area, mean pressure, peak pressure, and pressure time intervals will also be collected and assessed to determine pressure distribution of the foot.

Tertiary Outcome Measures:

1. Health relat
Sponsor: University of Colorado, Denver

Current Primary Outcome: Change in the amount of collapse [ Time Frame: Pre-operatively (3-12 months), 6 weeks, 6 months, and 1 and 2 years post-operatively ]

Measurement on radiographs of distance between heme clips located in calcaneous bone of the foot. Within the patient's own calcaneous bone, a heme clip will be placed on each side of the osteotomy. From post-operative radiographs, the amount of collapse will be determined by measuring the distance from one heme clip to the other. Post-operative changes in the distance between the clips from the first radiograph after surgery (used as a baseline, usually 6 weeks after surgery) indicate collapse of the graft.


Original Primary Outcome: The amount of collapse [ Time Frame: Up to 2 years postoperatively ]

Measurement on radiographs of distance between heme clips located in calcaneous bone of the foot. Within the patient's own calcaneous bone, a heme clip will be placed on each side of the osteotomy. From post-operative radiographs, the amount of collapse will be determined by measuring the distance from one heme clip to the other. Post-operative changes in the distance between the clips from the first radiograph after surgery (used as a baseline, usually 6 weeks after surgery) indicate collapse of the graft.


Current Secondary Outcome: Change in Plantar pressures [ Time Frame: Pre-operatively (3-12 months), then 1 and 2 years post-operatively ]

Plantar pressures values of interest are of six segments: medial heel, lateral heel, medial midfoot, lateral midfoot, first metatarsal and second metatarsal. The center of pressure index, total contact area, mean pressure, peak pressure, and pressure time intervals will also be collected and assessed to determine pressure distribution of the foot. Change from baseline (pre-operative measurements) will be evaluated up to 2 years post-operatively. The pre-operative plantar pressures must be within a year of the surgery.


Original Secondary Outcome: Plantar pressures [ Time Frame: Up to 2 years post-operatively ]

Plantar pressures values of interest are of six segments: medial heel, lateral heel, medial midfoot, lateral midfoot, first metatarsal and second metatarsal. The center of pressure index, total contact area, mean pressure, peak pressure, and pressure time intergrals will also be collected and assessed to determine pressure distribution of the foot. Change from baseline (pre-operative measurements) will be evaluated up to 2 years post-operatively. The pre-operative plantar pressures must be within a year of the surgery.


Information By: University of Colorado, Denver

Dates:
Date Received: February 26, 2014
Date Started: September 2010
Date Completion: August 2017
Last Updated: January 31, 2017
Last Verified: January 2017