Introduction
Instruments used in surgical procedures have the potential to break while in use, which can threaten patient safety. The rate of instrument breakage during emergency and elective orthopedic procedures is estimated to be between 0.18% and 0.35%.1,2 Drill bits are one of the most frequently broken surgical instruments.3–6 Retained drill bit fragments can threaten patient safety due to the potential for migration.3,7,8 This is especially dangerous when fragments are retained near the spine,7 pelvis,8,9 or close to neurovascular regions.6 Despite previous research outlining the prevalence of of and risks associated with broken drill bits, much of this research is derived from data from a single health system1,2,9 or case studies3,5,7,10 describing a single surgical case.
During a routine review of reports submitted to the Pennsylvania Patient Safety Reporting System (PA-PSRS)[1], we observed an increase in the number of events involving broken and retained drill bits during surgery. This led to an exploration of similar reports to summarize information related to broken surgical drill bits in Pennsylvania facilities. Our analysis will expand upon existing literature by including data from multiple facilities over a three-year period and providing prevention strategies from previous research and equipment manufacturers in a concise presentation.
Methods
Data Query
Data for this study were collected from event reports in the PA-PSRS database. PA-PSRS reports contain responses to structured fields (e.g., event date, patient age), as well as free-text narrative fields that allow reporters to describe event details in their own words. We queried the PA-PSRS acute care database for event reports submitted between January 1, 2021, and December 31, 2023, that contained the word “drill” within 10 characters of either “tip” or “bit” in the free-text fields (event details, event comments, event recommendations, event subtype - other). The query produced a total of 259 event reports that were manually reviewed for inclusion. Event reports met inclusion criteria if they described a drill bit breaking during a surgical procedure.
Variables Coded
We analyzed two sets of variables from the data available in the event reports. The first included patient age and sex, which were entered by the event reporter at the time of submission to PA-PSRS. The second set of variables was manually coded by the researcher and included the following:
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Procedure: Type of surgery that was being performed when the drill bit broke.
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Anatomic Location: Part of the patient’s body in which the drill bit broke or where the drill bit fragment was found.
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Timing of Discovery: When the broken drill bit, or drill bit fragment, was found in relation to the procedure.
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During Procedure: Any time during the procedure before closing (i.e., the time the surgical wound is stitched, stapled, or otherwise adhered as an end to the surgery).
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Postoperatively: Any time after the closing of the surgical wound.
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Unknown: The timing of discovery was unable to be determined from the information provided.
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Fragment Fate: The outcome involving the piece(s) of the broken drill bit after the original procedure (i.e., the procedure during which the broken drill bit occurred).
Data Analysis
We performed a descriptive data analysis to identify patient demographics and patterns in drill bit breakage.
Results
Demographics
Manual review of event reports identified a total of 156 relevant event reports from 72 facilities. Across all event reports, 59.6% (93 of 156) involved male patients, and 39.1% (61 of 156) involved female patients. The sex of two patients was not provided. The mean patient age was 52.2 years, ranging from 16 to 90 years. Over half (57.7%; 90 of 156) of the broken drill bit events occurred in patients over 50 years old.
Procedure and Anatomic Location
We were able to identify the type of procedure that resulted in a broken drill bit in 64 of the 156 event reports. Figure 1 shows the procedures related to a broken drill bit. Most broken drill bits occurred during a fracture repair (42.2%; 27 of 64) or a joint replacement surgery (20.3%; 13 of 64). Details of the fracture repairs and joint replacements are outlined in Table 1.
We were able to determine the anatomic location in which the drill bit broke in 108 of the 156 event reports. Broken drill bits most frequently occurred in the femur (25.0%; 27 of 108). Figure 2 shows the anatomic locations of the broken drill bits.
Timing of Discovery
Figure 3 shows the frequency and percentage of the timing of when the broken drill bit was discovered. In 93.6% (146 of 156) of event reports, the broken drill bit was discovered during the procedure. The broken drill bit was discovered postoperatively in 2.6% (4 of 156) of event reports.
Fragment Fate
We were able to determine the fate of the drill bit fragment(s) in 141 of the 156 event reports. The fragments were removed during the original procedure in 29.8% (42 of 141) of event reports. Over two-thirds (70.2%; 99 of 141) of the event reports indicate that the fragments were retained following the original procedure. Of the 99 event reports with a retained fragment, 97 describe no further intervention and two describe fragment removal during a subsequent surgery.
Discussion
Our analysis outlines the procedures, locations, discovery information, and fragment fate related to 156 events involving broken drill bits submitted by Pennsylvania facilities over a three-year period. Retained fragments from broken drill bits have the potential to negatively impact patient safety by requiring additional surgeries for removal, increasing exposure to unnecessary radiation from X-rays,11 and/or raising the risk of complications in the event of fragment migration.3,7
Although removing broken drill bit fragments is recommended,1,10 the risks must be weighed against the benefits. Removal can increase the risk of damage to surrounding areas, which may lead to surgeons deciding to leave the fragment in place.5,6 While the immediate risks of removal may outweigh the benefits, the risk to patient safety is a concern.3
Data from this analysis highlights procedures and anatomic locations that were reported to result in a broken drill bit. Our data shows that broken drill bits occur in both male and female patients and across a range of patient ages. While broken drill bits occurred most frequently during a fracture repair procedure, it is important to consider that fracture repairs are a common surgical procedure.12 This suggests that the high frequency of broken drill bits during fracture repairs could be due to the volume of fracture repair procedures and not because fracture repairs are at particularly high risk for drill bit breakage.
Our analysis shows that drill bit breakage occurred across a range of procedures and in varied anatomic locations, highlighting the need to understand and implement strategies to prevent drill bit breakage across all procedures. Due to the unknown cause(s) of drill bit breakage in our dataset, we chose to focus on existing literature and clinical knowledge when giving recommendations to prevent drill bit breakage. Previous research4,6,9,13 and information from medical device manufacturers14–16 provide strategies for preventing drill bit breakage during use in surgery. These strategies, which can be categorized as surgical technique; sterilization, reprocessing, and storage; and general safety measures, are provided in Table 2.
Limitations
The quality of information provided in the free-text fields of PA-PSRS event reports varies, and some reports contain more detailed information than others. Our analysis is limited by the information provided. With many event reports missing information related to the type of procedure and anatomic location, we did not explore relationships between these and other variables, as they may misrepresent true relationships and associations due to the missing data. We were also unable to determine the specific reason(s) for drill bit breakage because most event reports do not contain this type of detail. Furthermore, the exact cause may be unknown to the event reporter. In addition, despite mandatory reporting laws in Pennsylvania, it is possible that the events reported to PA-PSRS may not represent all occurrences of broken drill bits during surgery.
Conclusions
Previous literature1–6 has identified drill bits as surgical equipment that commonly breaks during use. This information, combined with data from this analysis describing fragments that were retained in high-risk anatomic locations or that required a return to surgery for fragment removal, shows that drill bit breakage can threaten patient safety in Pennsylvania. Implementing strategies to prevent drill bit breakage is key to reducing the potential negative impact on patient safety.
Notes
This analysis was exempted from review by the Advarra Institutional Review Board.
Data used in this study cannot be made public due to their confidential nature, as outlined in the Medical Care Availability and Reduction of Error (MCARE) Act (Pennsylvania Act 13 of 2002).
Disclosure
The author declares that they have no relevant or material financial interests.
About the Author
Christine E. Sanchez (chrsanchez@pa.gov) is a research scientist on the Data Science & Research team at the Patient Safety Authority (PSA). She is responsible for utilizing patient safety data, combined with relevant literature, to develop strategies aimed at improving patient safety in Pennsylvania.
PA-PSRS is a secure, web-based system through which Pennsylvania hospitals, ambulatory surgical facilities, abortion facilities, and birthing centers submit reports of patient safety–related incidents and serious events in accordance with mandatory reporting laws outlined in the Medical Care Availability and Reduction of Error (MCARE) Act (Act 13 of 2002).19 All reports submitted through PA-PSRS are confidential and no information about individual facilities or providers is made public.