Ankle Radiographs in the Early Postoperative Period: Do They Matter?

SLR - June 2014 - Nathan Coleman

Reference: McDonald M, Bulka CM, Thakore RV, Obremskey WT, Ehrenfeld JM, Jahanqir AA, Sethi MK. Ankle Radiographs in the Early Postoperative Period: Do They Matter? Journal of Orthopaedic Trauma. 2013 Dec 26; [Epub ahead of print].

Scientific Literature Review

Reviewed By: Nathan Coleman, DPM
Residency Program: Trinity Regional Medical Center, Fort Dodge, IA

Podiatric Relevance: National healthcare expenditures represented nearly 18 percent  of the United States Gross Domestic Product (GDP) in 2010 and are projected to increase to 25 percent  of the US GDP by 2025. A major driver in increasing healthcare costs includes unnecessary expenditures associated with medical imaging. There are over 575,000 ankle fractures in the US population each year with many of them being treated by podiatric surgeons. A large variety of postoperative evaluation protocols exist with numerous physicians opting to order early radiographs to assess accurate alignment of fracture fragments or stability of hardware. Medical imaging expenses represent approximately 75 percent  of total monthly and annual costs for the average orthopedic surgeon. This study attempted to determine whether or not obtaining the two-week (early) post op x-ray is associated with the advantage of fewer complications in patients with operatively treated ankle fractures. If no advantage is noted, this could identify a potential target for healthcare cost savings and reduced resource utilization.

Methods: All patients who underwent surgical fixation for an ankle fracture at the author’s institution between January 1, 2001 and January 1, 2010 were identified through a retrospective Current Procedural Terminology (CPT) code search. No standard treatment protocol was utilized in the care of the fractures. Typical management included immediate or delayed surgery based on soft tissue swelling and joint congruity, postoperative splinting, suture removal two to three weeks following surgery, intraoperative or postoperative x-rays, and two-week x-rays at first follow-up. Based on attending preference, patients were casted or in a protective boot for six weeks. Ankle fractures without syndesmotic injury were typically non-weight-bearing for 6-8 weeks while those with syndesmotic injury were non-weight-bearing for 10 weeks. 

After the CPT search, patients were organized into “early” and “late” x-ray groups based on when the first postoperative x-ray was taken. The early period was defined as postoperative days 7-21, whereas the late period was defined as postoperative days 22-120. A total of 1,411 charts met the inclusion criteria and were used for analysis. 889 patients (63 percent ) received x-rays in the early period compared to 522 (37 percent ) patients in late period. Charts in which the first postoperative x-ray was not taken between days 7-120 postoperatively, incomplete charts, or patients with open fractures of the ankle were excluded.

Complete charts were further reviewed for any complications from the point of operative fixation to discharge from the clinic. Complications consisted of infection, improper bone healing (nonunion, malunion, delayed union), hardware issues, and wound dehiscence requiring surgical intervention. After final criteria were met, qualifying charts were analyzed through multiple forms of statistical measurements.

Results: A total of 99 charts were confirmed to have complications related to the ankle fracture. Approximately 7.0 percent  of patients in the early x-ray group developed a complication compared to 5.9 percent  for the late x-ray group. There was no significant association between postoperative complications and the timing of the first postoperative x-ray (p = 0.4492). Patients who had x-rays taken in the early period or had complications did show a higher average total number of x-rays taken in the postoperative period.

Conclusions: The results of this study show no significant association between postoperative complications and the timing of postoperative x-rays in the treatment of ankle fractures. Therefore, in the absence of clinical indications, the first x-ray after surgical treatment may be taken beyond two weeks without an increased risk of complications. Using a conservative Medicare payment x-ray cost of $21.45 by averaging the costs of two-view and three-view x-ray costs, and given that approximately 575,000 ankle fractures occur each year, eliminating an average of just a single x-ray per patient could save approximately $12.3 million. Certainly, surgeons must use their judgment and not hesitate to utilize imaging when clinical scenarios necessitate radiographic evaluation such as in noncompliant patients or those with tenuous fixation even in the early postoperative period. Nevertheless, the study results identify the questionable benefit of the routine early postoperative radiographs for all patients and identify an opportunity to reduce healthcare costs without compromising patient care.