Session XI - Tibia

Sat., 10/7/06 Tibia, Paper #63, 11:15 am

Clinical Usefulness of a Commonly Used Research Criterion to Diagnose Radiographic Healing in Diaphyseal Fractures Treated with an Intramedullary Device

Matthew R. Bong, MD (*); Thuan Ly, MD; Michael J. Bosse, MD (*);
Carolinas Medical Center, Charlotte, North Carolina, USA

Purpose: A commonly used, FDA-accepted research criterion for radiographic healing in diaphyseal fractures treated with intramedullary fixation has been the presence of bridging bone in three out of four cortices seen on anteroposterior (AP) and lateral radiographs. The purpose of this study was to determine the clinical usefulness of this criterion in the evaluation of diaphyseal tibial and femoral fractures treated with an intramedullary device.

Methods: We retrospectively reviewed the medical records of 230 patients (247 fractures) who underwent intramedullary nailing for diaphyseal tibial and femoral fractures between December 2003 and April 2005. Patients were followed clinically until pain-free with normal activities and had radiographic evidence of bridging cortical bone. The diagnosis of nonunion was made in a painful fracture with no evidence of either bridging bone or progressive healing on AP or lateral radiographs. The final radiographs of all patients discharged from clinic with a diagnosis of a healed fracture were evaluated using the criterion of three out of four cortices.

Results: 125 patients (137 fractures) had complete follow-up. There were 39 females and 86 males. Follow-up averaged 9.9 months (range, 3-26). The average age was 34 years. There were 71 femur fractures and 66 tibia fractures. Thirteen of the 137 (9.5%) fractures did not meet the criterion of bridging bone in three out of four cortices but did have evidence of some bridging cortical bone and were pain-free. Twelve of these thirteen patients had returned to their preinjury occupation. Thirteen factures (9 tibias and 4 femurs [9.5%]) were diagnosed as a symptomatic nonunion. Five of these healed after nonunion surgery. There was a statistically significant 2.0-fold increase in the number of patients who did not meet the research criterion of radiographic healing (19.0%) compared to those who were diagnosed with a symptomatic nonunion (9.5%; P =0.026).


Conclusion: Using the presence of bridging bone in 3 out of 4 cortices on AP and lateral radiographs as a criterion to document healing of diaphyseal tibia and femur fractures treated with an intramedullary implant does not appear to be clinically relevant. There is a subset of patients who do not meet this criterion who appear to have physiologically healed, pain-free fractures that are stable with an intramedullary device in place. Using the accepted 3 out of 4 cortices criterion will overestimate the rate of fractures that are not healed (by a factor of 2.0 in the current study) and could lead to false interpretation of research data or unnecessary surgical intervention.

If noted, the author indicates something of value received. The codes are identified as a-research or institutional support; b-miscellaneous funding; c-royalties; d-stock options; e-consultant or employee; n-no conflicts disclosed, and *disclosure not available at time of printing.
· The FDA has not cleared this drug and/or medical device for the use described in this presentation (i.e., the drug or medical device is being discussed for an "off label" use). · · FDA information not available at time of printing.