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Updated: Feb 26, 2026

A Reliable and Reproducible Critical-Sized Segmental Femoral Defect Model in Rats Stabilized with a Custom External Fixator
Published on: March 24, 2019
Staged reconstruction of diaphyseal fractures with segmental defects: Surgical and patient-reported outcomes
S D Zoller1, L A Cao2, R A Smith1
1Department of Orthopaedic Surgery, University of California, Los Angeles (UCLA), 1250 16th St. Suite 2100, Santa Monica CA 90404, United States.
Introduction:
Two-stage limb reconstruction is an option for patients with critical size segmental bone defects following acute trauma or non-union. Reconstruction is technically demanding and associated with a high complication rate. Current protocols for limb reconstruction have well-documented challenges, and no study has reported on patient outcomes using a validated questionnaire. In this study, we aimed to examine the clinical and patient-centered outcomes following our surgical protocol for two-stage limb reconstruction following critical size segmental defects.
Patients And Methods:
A single surgeon performed reconstruction of long bone defects using antibiotic impregnated cement spacers and intramedullary cancellous bone autograft. A retrospective chart review was performed. Three reviewers independently measured time to union based on radiographs. The Lower Extremity Functional Scale (LEFS) survey was administered to patients after most recent follow-up.
Results:
Ten limbs representing nine patients were included. All patients sustained a lower extremity injury, and one patient had bilateral lower extremity injuries. Average clinical follow-up was 18.3 months (range 7-33) from final surgical intervention, and follow-up to questionnaire administration was 28 months (range 24-37). The mean time between stages was 3.1 months. Average time to unrestricted weight-bearing was 7.9 months from Stage 1 (range 3.4-15.9) and 4.5 months from Stage 2 (range 1.1-11.6). Average time to full union was 16.7 months from Stage 1 (range 6.4-28.6) and 13.5 months from Stage 2 (range 1.8-27). Eight patients (nine limbs) participated in the LEFS survey, the average score was 53.1 (range 30-67), equating to 66% of full functionality (range 38%-84%). Complications included 5 infections, 3 non-unions, and one amputation. There was a moderate positive correlation between infection at any time point and non-union (R=0.65, p=0.03).
Discussion And Conclusions:
Outcomes in this small patient cohort were good despite risks of complication. There is an association between infection and non-union. Further studies addressing clinical and functional outcomes will help to guide expectations for future surgeons and patients.
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