There is in the orthopaedic community increasing interest in how to accurately determine when a patient who has undergone surgery or has recovered from a musculoskeletal condition may return to driving in a safe manner. This decision can carry major implications with regard to patient and public safety and traditionally has been based on clinical judgment rather than clinical data. Physician recommendations have been highly variable1 and have been made primarily on the basis of individual physician experience and knowledge of the patient's limitations and injuries. Recommendations are usually offered with the implicit understanding that compliance is, ultimately, the patient's responsibility. Furthermore, without standardized guidelines or hard clinical data to support it, the orthopaedist's recommendation on when the patient can safely return to driving is often met with opposition by the patient and is rarely definitive, often resulting in a "negotiation" that reaches a mutually acceptable compromise between physician and patient.
Recently, various factors have increased practitioner awareness of the difficulty in making the decision and the potential implications of an improper recommendation regarding when a patient can return to driving. These factors include the perception of a more uncertain medico-legal environment1,2, recognition of the highly variable legislation from state to state3, an ever-decreasing patient-physician interaction time in the clinical setting (resulting in a decreased ability to judge a patient's ability to drive), and an expanding population of aging patients who are often reluctant to give up the freedoms afforded by the ability to drive4. An increased awareness of these factors has generated calls for a more analytical decision-making process with more consistent clinical guidelines from government or professional medical societies, and it has also resulted in an increased number of studies and surveys to address the issue. Recent studies surveying the attitudes of practitioners1 and patients regarding the decision on returning to driving have offered potential solutions, such as the implementation of consistent return-to-driving policies within a practice group and mandatory recertification for all patients. There have also been calls for more consistent legislation as well as for more accessible state-level recertification pathways for assessing when a patient has recovered from injury. Recent improvements include the availability of specialized physical and occupational therapy programs that address return to driving4, as well as resources such as the National Highway Transportation Safety Administration guidelines for the assessment and counseling of older drivers3.
In addition to physician concern for patient and public safety, an increased fear of medico-legal exposure of litigation may also be fueling interest on the issue. While, as of the date of this writing, no litigation against a physician has alleged that there was improper return-to-driving advice, the precedent already exists in Massachusetts for physician involvement in litigation arising from alleged poor advice to a patient regarding driving during the time that a prescribed narcotic medication was being used5. A recent survey of our practice revealed that up to 30% of patients who have undergone orthopaedic treatment under our care returned to driving while still taking narcotic medication prescribed by clinicians in our group1. An increased awareness of driving safety with regard to injured and elderly patients is no longer only of interest to the medical community but is now also of interest to the general public. Local and national media have focused on many tragic events involving impaired senior drivers as well as incidents resulting from distractions such as texting and cell phone use, all of which seem to be fueling increased public concern and a political response. Massachusetts has just enacted new legislation regarding safety and driving6. In addition to banning text messaging for all drivers, prohibiting junior operators from using cell phones while driving and placing restrictions on cell phone use by operators who are eighteen years of age or older, and increasing at-fault penalties, House bill H4795 also expands physician access to report impaired drivers and extends liability protection to those physicians who decide to do so.
It is in this environment that increased clinical and scientific studies reporting new data are highly welcome. Studies in recent years have reported, in one form or another, braking times under different conditions and after different procedures. A most recent addition is the present study by Orr et al. The authors demonstrated increased total brake-response times in healthy individuals when they wore a controlled-ankle-motion boot or a short leg cast or when they made use of a left-foot driving-adapter device as compared with when they wore normal footwear. While increased braking time responses have already been described with immobilization devices7, this is the first study reporting on the potential safety of a left-foot driving-adapter device. This device consists of a transient mechanical modification to the pedal arrangement, in which the accelerator is transferred to the left of the brake pedal in a vehicle with automatic transmission so that it may be operated with an uncompromised left foot. Not always an inexpensive modification, it is one option suggested by physicians to patients with right lower-extremity compromise as a means of allowing them to return to driving earlier than otherwise. Patients who opt for this alternative undergo the expense of the modification and, it has been the belief, may return to driving soon after injury with a similar expectation of safety as they would have with normal driving. The conclusions by Orr et al. do not support this assumption, and the authors recommend against the use of such devices.
The authors' methodology follows the well-established model of testing individuals in a computerized driving simulator. Limitations of the study parallel those of recent studies in the literature that have explored the same issue in normal healthy volunteers; that is, measured decreased response times may not truly reflect what may be exhibited by an injured, medicated, or elderly patient in a real-life situation. Thus, the absolute measures (in milliseconds) of reported delays are not realistic values to guide advice to patients. However, one rests on good ground assuming that an injured patient can only have slower response times and thus be at higher risk. Another concern is that driving is a multisystem task involving many parameters other than braking response time. By focusing only on this variable, we risk equating it to a quantitative measure of safety. In reality, many motor-vehicle accidents may not be related to delays in brake application as much as they may be secondary to impaired judgment or inattention. Narcotic use, vision changes, pain, cognitive impairment, and other stresses related to recent injury or surgery may impair driving safety in ways that cannot be experimentally categorized or quantified.
In conclusion, the study by Orr et al. follows the trend of recent experimental studies that have attempted to address a concern of increasing interest to the practicing surgeon. It confirms the increased brake-response times that have been reported by others when patients wear a controlled-ankle-motion boot or traditional short leg cast and, furthermore, it does not recommend the use of a left-foot driving-adapter device. This last recommendation alone makes the study a worthwhile contribution to the existing literature.