Stryde Weight-bearing Internal Lengthening Nail

Abstract

Since May 2018, 106 patients (187 limb segments) have completed internal lengthening with the Stryde implant. Fifty-seven skeletally mature patients (12 female and 45 male) underwent cosmetic stature lengthening of the femur (41), tibia (4), or combined bilateral femur and tibia (12). Forty-nine other patients (ages 9 to 60 y) with a variety of limb length discrepancy etiologies including metabolic, congenital, genetic, and posttraumatic, underwent unilateral lengthening of the femur (37) or tibia (12). All patients undergoing lengthening alone were allowed immediate full weight-bearing as tolerated. Patients with secondary ipsilateral acute deformity corrections had restricted weight-bearing until sufficient healing was present at the metaphyseal site. The mechanical axis deviation following lengthening was not statistically significantly related to limb segment, patient weight, nail diameter, or distraction amount, but tended towards varus in the femurs and valgus in the tibias. Fifty-two stature patients and 43 unilateral patients lengthened to within 10 and 5 mm of their goals, respectively. One tibial nail stopped functioning prematurely and was exchanged to complete the lengthening. Seven patients required secondary unplanned operations. Successful outcomes were achieved in all patients. Strict adherence to careful preoperative planning, and postoperative lengthening protocols including specialized limb lengthening physiotherapy are important to the success. There were no issues related to biological incompatibility of the Biodur 108 alloy stainless steel from which the implant was fabricated.