Tag Archive | bone defect

Factors Affecting Union after Capanna Reconstruction

Resection of long-bone tumors often leaves large skeletal defects. Since the late 1980s, surgeons have used the “hybrid” Capanna technique—a vascularized fibular graft inlaid in a massive bone allograft—to fill those voids, with good functional outcomes reported. In the November 20, 2019 issue of The Journal of Bone & Joint Surgery, Li et al. report on factors influencing union after the Capanna technique.

The authors radiographically evaluated Capanna-technique reconstructions in 60 patients (10 humeral, 33 femoral, and 17 tibial) and correlated allograft-host union time to the following variables:

  • Patient age
  • Tumor site
  • Adjuvant treatment (e.g., chemotherapy)
  • Previous surgical procedures
  • Defect length
  • Fixation method
  • Fibular viability (assessed with a bone scan 10 days after reconstruction)

They also histologically analyzed a retrieved specimen from one patient.

Among these 60 reconstructions, the mean defect length was 16 cm, and the mean time to union of the constructs was 13 months. The overall survival rate of the constructs was 93% at the latest follow-up.

Multivariate linear regression revealed no correlation between allograft-host osseous union time and patient age, defect length, tumor site, or fixation method. Conversely, devitalization of the transplanted fibular graft, chemotherapy administration, and a previous surgical procedure were associated with a prolonged union time. Histologically, the allograft-host cortical junction was united by callus from periosteum of both the host bone and the fibular graft.

Li et al. conclude that “ensuring patent vascular anastomoses of the transplanted fibula is crucial to prevent delayed or nonunion.” They also suggest that Capanna-technique patients who have any of the 3 “adverse factors” noted above should be treated with extended postoperative immobilization and delayed weight-bearing.

JBJS 100: Proximal Humeral Fractures, Stem Cells

JBJS 100Under one name or another, The Journal of Bone & Joint Surgery has published quality orthopaedic content spanning three centuries. In 1919, our publication was called the Journal of Orthopaedic Surgery, and the first volume of that journal was Volume 1 of what we know today as JBJS.

Thus, the 24 issues we turn out in 2018 will constitute our 100th volume. To help celebrate this milestone, throughout the year we will be spotlighting 100 of the most influential JBJS articles on OrthoBuzz, making the original content openly accessible for a limited time.

Unlike the scientific rigor of Journal content, the selection of this list was not entirely scientific. About half we picked from “JBJS Classics,” which were chosen previously by current and past JBJS Editors-in-Chief and Deputy Editors. We also selected JBJS articles that have been cited more than 1,000 times in other publications, according to Google Scholar search results. Finally, we considered “activity” on the Web of Science and The Journal’s websites.

We hope you enjoy and benefit from reading these groundbreaking articles from JBJS, as we mark our 100th volume. Here are two more:

Displaced Proximal Humeral Fractures: Classification and Evaluation
C Neer: JBJS, 1970 September; 52 (6): 1077
Complex distal humeral fractures have long challenged orthopaedic surgeons and their patients. Often the first step in fracture-management decision-making is classification, and in this 1970 study, Dr. Neer proposed a 6-group classification based on the presence or absence of displacement of one or more of the four major proximal segments. Since then, this classification has been variably adapted by multiple authors, but its usefulness remains intact.

The Effect of Implants Loaded with Autologous Mesenchymal Stem Cells on the Healing of Canine Segmental Bone Defects
S F Bruder, K H Kraus, V M Goldberg, S Kadiyala: JBJS, 1998 July; 80 (7): 985
Research into mesenchymal stem cells (MSCs) to augment healing of tendons, chondral and bone defects, and other connective tissues has taken off since these authors used autologous MSCs to help heal 21-mm segmental femoral defects. Radiographic union occurred rapidly at the interface between host bone and porous ceramic cylinders loaded with MSCs, and a large collar of bone had formed around the cell-loaded implants after 16 weeks.