Commentary & Perspective

Commentary & Perspective on
"Treatment of Distal Femoral Nonunion with Internal Fixation, Cortical Allograft Struts, and Autogenous Bone-Grafting"
by Jun-Wen Wang, MD, and Lin-Hsiu Weng, MD

Commentary & Perspective by
Marc F. Swiontkowski, MD*,
Department of Orthopaedic Surgery, University of Minnesota, Minneapolis, MN

With improved techniques of internal fixation, nonunions of distal femoral fractures can generally be avoided, but when they do occur, it is most frequently in patients who have very poor bone density, serious health problems, and limited mobility. In this issue of The Journal, Wang and Weng have provided data to support the use of a combination of techniques for effective treatment of difficult nonunions of the distal femur—specifically, internal fixation with the adjunctive use of cortical allograft struts and autogenous bone-grafting.

This retrospective cohort study provides detailed information on thirteen patients with a distal femoral nonunion treated with rigid internal fixation in combination with frozen cortical strut allografts of substantial length. Ten of the nonunions were fixed with blade-plates or condylar buttress plates; two, with an antegrade locked nail; and one with an antegrade locked nail and a compression plate. The strut allografts, of various widths, had an average length of 10 cm. The authors reported reasonable functional results with knee scores according to The Hospital for Special Surgery knee rating system that improved from an average of 20 points preoperatively to 71 points at the latest follow-up examination. The range was extremely broad—5 to 44 points preoperatively and 48 to 100 points at the latest follow-up examination. The average arc of motion increased by 28° postoperatively, but at the final end point, the arc of motion was still less than 90° in seven patients and was somewhat compromised in the remainder. Osteoarthritis of the knee and extension contractures in a number of patients complicated the management of this difficult entity.

The most important outcome was that there was no loss of fixation in any patient. The rigid internal fixation helped to maintain alignment of the femur in the coronal plane. Two patients had positive cultures of specimens obtained intraoperatively at the time of the revision surgery and both were treated successfully with antibiotic therapy. The observation that infection associated with nonunion resolves in patients treated with rigid internal fixation was again supported by this finding.

Management of osteoporotic distal femoral nonunions with rigid internal fixation and adjunctive strut allografts is a useful tool for the orthopaedic surgeon. These nonunions, however, are best dealt with by prevention. With newer fixation techniques, such as locking plates or retrograde nailing, which allows limited operative exposure, even the most compromised and obese patients will be less likely to have a nonunion. This retrospective study demonstrates that internal fixation with adjunctive cortical strut allografts and autogenous bone-grafting is a useful technique for achieving successful healing of distal femoral nonunions.

*The author did not receive grants or outside funding in support of his research or preparation of this manuscript. He did not receive payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, educational institution, or other charitable or nonprofit organization with which the author is affiliated or associated.