OTA 1998 Posters

Reamed Versus Non-Reamed Intramedullary Nailing of Lower Extremity Long Bone Fractures: A Meta-Analysis of the Literature

Mohit Bhandari, MD; Anthony Adili, MD; Doris Tong, MD; Richard Lachowski, MD; Desmond Kwok, MD; Stephen Shaughnessy, PhD, McMaster University, Hamilton, Canada

Background: The choice of reamed versus non-reamed intramedullary (IM) nailing of lower extremity long bone fractures remains controversial. Recent randomized controlled trials on this topic have lacked sufficient power to make conclusions regarding their primary outcomes-nonunion rates.

Purpose: To determine the effect of reamed and non-reamed IM nailing of lower extremity long bone fractures on the rates of nonunion. Subsidiary outcomes of implant failure, malunion, compartment syndrome, pulmonary embolus, and infection rates were also reviewed.

Design: Quantitative systematic review of prospective, randomized controlled trials.

Data Identification: Computerized databases (MEDLINE and SCISEARCH) were searched for published randomized clinical trials from 1969-1998. Additional studies were identified through extensive hand searches of major orthopaedic journals, bibliographies of major orthopaedic texts, and personal files.

Study Selection and Data Extraction: A total of 675 citations were identified of which 86 were felt to be potentially eligible. Utilizing pre-defined selection criteria, "study title" review eliminated 26 studies. 60 abstracts were independently reviewed by 3 investigators and 4 studies were identified for inclusion. An additional 4 "unpublished" studies were identified and included in a separate analysis. Study quality was assessed and relevant descriptive information was abstracted.

Results: Statistical pooling of the 4 published studies (n=359) was conducted since the studies were homogenous (test of heterogeneity, p>0.1). The risk ratio for nonunion following reamed IM nailing was 0.43 (95% CI, 0.19-0.99, p=0.04). The absolute risk difference in nonunion rates with reamed IM nailing was 7.0% (95%CI, 1-11%). Thus, 1 nonunion could be prevented for every 14 patients treated with reamed IM nailing (NNT=14.28). Addition of the 4 unpublished studies (total 8 studies, n=565 patients) further improved the precision of the risk ratio estimate for nonunion following reamed IM nailing ( 0.33, 95%CI 0.16-0.68 , p=0.0037). The risk ratios for subsidiary outcome measures were: implant failure 0.30 (95%CI, 0.16-0.58, p<0.001), malunion 1.06 (95%CI, 0.32-3.57), pulmonary embolus 1.10 (95%CI, 0.26-4.76), compartment syndrome 0.45(95%CI,0.13-1.56), and infection 0.98 (95%CI,0.21-4.76). Sensitivity analyses suggested that reported rates of nonunion and implant failure were higher in studies of lower quality. The type of long bone fractured (tibia/femur) or degree of soft tissue injury (open/closed) did not significantly alter the risk ratios for nonunion between reamed and non-reamed IM nailing.

Conclusions: There is evidence from a pooled analysis of randomized trials that reamed IM nailing of lower extremity long bone fractures significantly reduces rates of nonunion and implant failure.