Does the brake response time of the right leg change after left total knee arthroplasty? A prospective study

Break Reaction Time after Conservatively Treated Ligament Ruptures of the Ankle

BACKGROUND

Ankle sprain lesions are the most common ligament lesions in humans. One particularly dangerous consequence of this pathology is an inability to quickly and sufficiently depress the brake pedal when driving a car. The high incidence of the lesion, in the context of a society that is highly automobile-dependent, makes the question "When can a patient safely drive a car again?" of particular socioeconomic importance.

HYPOTHESIS/PURPOSE

Though orthopaedic physicians are often confronted with this question, finding an answer in the sparse literature on the topic proves difficult. This study aims to provide a definitive answer to this question.

STUDY DESIGN

Prospective Case Control Study.

METHODS

30 patients with grad II and III ligament injuries of the right ankle (18 women, 12 men) and 30 healthy volunteers (19 women, 11 men) participated in this study. Brake reaction time (BRT) was assessed using a previously reported custom-made driving simulator. BRT was assessed two, four and six weeks after injury. Simultaneously the American Orthopedic Foot and Ankle Society Ankle Hindfoot Score (AOFAS-AHS) was assessed.

RESULTS

Two weeks after the incident, the patients' BRT measured 690.6±186.2ms. Four weeks after the incident, the BRT improved to 551.8±137.3ms (p<0.001). Compared to the healthy controls' BRT (553.6±118.6ms), there were no significant differences 4 weeks after the injury (p=0.473). At this time, the BRT of both groups was also well below (i.e. faster) than the recommendations of road authorities (700-1500ms). An AOFAS-AHS score of more than 80 points correlated with a sufficient BRT.

CONCLUSIONS

Four weeks post injury, patients generally had a sufficient BRT to drive in traffic safely. Some patients could achieve sufficient BRTs at an earlier stage. All patients with sufficient BRTs had an AOFAS-AHS score of ≥81 points. The AOFAS-AHS score can therefore be regarded as an adequate screening tool to evaluate which patients are ready to safely operate motor vehicles earlier.

Doctor when can I drive? Braking response after knee arthroplasty: A systematic review & meta-analysis of brake reaction time

BACKGROUND

There is limited evidence available on return to driving for patients undergoing knee arthroplasty (KA). Primarily, surgeons have used brake reaction time as a surrogate measure of safe return to driving. The purpose of this study was to review existing literature and provide guidance on the recovery of braking performance following knee arthroplasty.

METHODS

A literature search was performed for prospective studies on driving after KA. Two reviewers screened citations for inclusion, assessed methodological quality, and extracted data. Values for total brake reaction-time (TBRT), movement-time (MT), reaction-time (RT), and braking-force (BF) were included for meta-analysis.

RESULTS

Twelve studies with 368 subjects were identified. TBRT, RT, MT, and BF relative to preoperative baseline were assessed. Meta-analysis of TBRT showed a significant improvement from preoperative baseline at 3 months & 1 year (p = 0.003 & p = 0.0001). MT showed a significant increase at 2 and 4 weeks (p = 0.00001 & p = 0.03) before returning to no being significantly different at 6 weeks and beyond. In contrast RTs were noted to improve significantly 2 weeks (p = 0.006), 4 weeks (p = 0.03), and 1 year (p = 0.0002).

CONCLUSION

Meta-analysis showed no significant difference in TBRT up until 3 months. RT increased significantly post-operatively suggesting it is not a reliable indicator. MT in contrast was significantly decreased post KA and may represent a more reliable measure of braking performance post KA. Surgeons should consider these recommendations and other patient factors that determine fitness to drive prior to advising their patients on a safe to return to driving.

Driving ability after right-sided inguinal hernia surgery

PURPOSE

To investigate driving ability (brake reaction time, BRT) after right-sided hernia repair. It was assumed that postoperatively BRT would be impaired as compared to the preoperative reference and healthy controls.

METHODS

BRT was prospectively collected from 30 patients undergoing hernia repair [Lichtenstein or total extraperitoneal endoscopic procedure (TEP)]. BRT was measured with a driving simulator preoperatively and on postoperative days 2 and 14. After receiving a visual stimulus, the patients had to apply the brake pedal with 160 N. The average of ten runs was used as the patient's BRT value.

RESULTS

Thirty patients completed all measurements. In the Lichtenstein group, BRT was significantly impaired as compared to the patient's preoperative values (p = 0.021). Two weeks after surgery BRT had returned to the preoperative level (p = 0.859). BRT in the Lichtenstein group was also significantly impaired 2 days postoperatively as compared to the BRT of 60 healthy controls (p = 0.001). In the TEP group, no impaired BRT was detected.

CONCLUSIONS

Based on our finding of significantly impaired BRT in patients following right-sided Lichtenstein hernia repair, it seems wise to recommend that such patients refrain from driving for 2 weeks after surgery. No such impairment was found in patients following TEP surgery. Consequently, it is deemed safe for them to resume driving 2 days after the procedure.

Reaction time and brake pedal force after total knee replacement: timeframe for return to car driving

PURPOSE

This prospective cohort study aimed to examine objective and subjective parameters in patients who underwent total knee replacement (TKR) to assess from when on driving a car can be deemed safe again.

METHODS

Thirty patients (16 women, 14 men, age 66 ± 11 years) who received TKR of the right knee and 45 healthy controls (26 women, 19 men, age 32 ± 9 years) were asked to perform an emergency braking manoeuvre using a driving simulator. Brake pedal force (BPF), neuronal reaction time (NRT), brake reaction time (BRT), and subjective parameters (pain, subjective driving ability) were measured preoperatively as well as 5 days, 3-4, and 6 weeks after TKR.

RESULTS

Preoperative NRT was 506 ± 162 ms, BRT 985 ± 356 ms, and BPF 614 ± 292 N. NRT increased to 561 ± 218 ms, BRT to 1091 ± 404 ms and BPF decreased to 411 ± 191 N 5 days after TKR. Three weeks after surgery, NRT was 581 ± 164 ms and BRT 1013 ± 260 ms, while BPF increased to 555 ± 200 N. Only BPF showed significant differences (p < 0.01). In week 6, all parameters were restored to baseline levels; patients showed significant pain decrease and evaluated their driving ability as "good" again.

CONCLUSION

BPF was the only parameter displaying a significant postoperative decrease. However, preoperative patients' baseline levels and subjective confidence in driving ability were only reached 6 weeks after the operation. These results indicate that a minimum waiting period of 6 weeks should be considered before patients can safely participate in road traffic at their individual preoperative safety level again.

LEVEL OF EVIDENCE

II.

Clinical Considerations for Return to Driving a Car following a Total Knee or Hip Arthroplasty: A Systematic Review

Aim

The purpose of this study is to systematically review patient characteristics and clinical determinants that may influence return to driving status and time frames following a primary TKA or THA and provide an update of the current literature.

Methods

This review was completed per the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Final electronic database searches were completed in October 2019 in Medline/PubMed, Medline/OVID, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Cochrane Library using preselected search terms. Manuscripts of prospective and nonrandomized studies that examined the return to driving a car after a primary knee or hip arthroplasty patients were included. The Methodological Index for Non-Randomized Studies was used to measure study quality. Two authors selected studies and assessed their qualities. All disagreements were resolved through discussion and, as needed, a third reviewer. Data on study title, author(s), country, year, study design, sample size, inclusion and exclusion criteria, age, BMI, gender, statistical analyses, driving measure, follow-up time, surgical approach, laterality, and postoperative management were extracted from each study.

Results

A total of 23 studies were eligible, including 12 TKA studies (n = 654) with mean ages between 43 and 82 years, 9 THA studies (n = 922) with mean ages between 34 and 85 years, and 2 combined TKA and THA (TKA, n = 815; THA, n = 685), yielded MINORS scores between 6 and 12. Most patients achieved or exceeded preoperative response times between 1 and 8 weeks following a TKA and 2 days to 8 weeks following a THA, and/or self-reported return to driving between 1 week and 6 months. Influences on return to driving time included laterality and pain, but gender was mixed. Discussion/

Conclusions

Study results were consistent with previous systematic reviews in that return to driving a car after a primary TKA or THA is highly variable, and most commonly occurs around 4 weeks, but can range between 2 and 8 weeks. While various patient and clinical factors can influence return to driving for a TKA or THA, the most common contributing facts were pain and laterality. The heterogeneous nature of the studies prevented a meta-analysis for determining contributions of return to driving following a primary TKA or THA. Regardless, this study updates previous systematic reviews and presents insight on patient and clinical factors beyond generalized timeframes for return to driving a car. This information and results from future studies are essential to guide clinical recommendations and patient and clinician expectations for return to driving a car after a primary TKA or THA.

Braking reaction time before and after surgery for patients with recurrent lumbar disc herniation

OBJECTIVE

The positive effect of primary lumbar disc surgery on braking reaction time (BRT) has already been shown. The authors investigated the effect of recurrent lumbar disc herniation surgery on BRT.

METHODS

Twenty-four patients (mean age 49.9 years) were investigated for BRT 1 day before surgery, postoperatively before hospital discharge, and 4 to 5 weeks after surgery. Thirty-one healthy subjects served as a control group.

RESULTS

Significant improvement of BRT following surgery was found in all patients (p < 0.05). For patients with right-sided recurrent disc herniation, median BRT was 736 msec before surgery, 685 msec immediately postoperatively, and 662 msec at follow-up. For patients with left-sided recurrent disc herniation, median BRT was 674 msec preoperatively, 585 msec postoperatively, and 578 msec at follow-up. Control subjects had a median BRT of 487, which differed significantly from the patient BRTs at all 3 test times (p < 0.05).

CONCLUSIONS

A significant reduction in BRT in patients with recurrent disc herniation was found following lumbar disc revision surgery, indicating a positive impact of surgery. Due to the improvement in BRT observed immediately after surgery, we conclude that it is appropriate to recommend that patients keep driving after being discharged from the hospital.

Estimating Braking Performance in Osteoarthritis of the Knee or Hip with a Reaction Timer

Objective

To investigate if testing in a brake simulator can be replaced by a simple reaction timer setup imitating the ergonomic conditions of emergency braking when evaluating the ability to drive in patients with musculoskeletal problems of the lower extremities.

Methods

A cross‐sectional survey was performed in the Department of Orthopaedic Surgery in our University Hospital from October 2014 until May 2015. Patients attending our department with either osteoarthritis or arthroplasty of the knee or hip were asked to participate in the study if they had a valid driving license. The age limit was from 18 to 85 years. Both women and men were included. Registered demographic data were patient age, height, sex, body weight, and body mass index. Braking performance (brake response time [BRT]) was evaluated in a brake simulator that was embedded into a real car cabin (10 measurements). The values obtained were compared with those registered when simply testing (5 measurements) those patients with a normal reaction timer setup that imitated the sitting position in a car. Kendall's tau correlation coefficient was calculated between the values obtained from the brake simulator with those from the reaction timer setup.

Results

Altogether, 137 patients (median age 67 years [range, 24–89 years]) with either osteoarthritis of the knee (n = 55) or hip (n = 82) were tested. Age was comparable in both collectives (P = 0.807). The mean body height was 1.70 m in both groups. Knee patients presented with a higher body weight of approximately 5 kg (P = 0.014) and consequently also had a higher body mass index (P = 0.023). The median BRT in the brake simulator was 628 ms (range, 390–1444 ms) for all subjects: 592 ms (range, 418–1146 ms) in the hip group and 696 ms (range, 390–1444 ms) in the knee group. Measurement values obtained by the reaction timer were significantly (P < 0.001) higher by approximately 15% (SD, 22%) than those measured in the brake simulator. A moderate correlation was found between the reaction timer and the brake simulator, with a Kendall's tau of 0.449 (P < 0.001) for all patients. Interestingly, hip patients showed a higher correlation (τ = 0.471) than knee patients (τ = 0.263).

Conclusion

Even though the measured correlations do not allow us to make a definite statement concerning braking performance, especially in knee patients, a simple reaction timer test can provide a low‐cost first estimate of BRT for patients and their treating physicians. For forensic statements, the brake simulator will, however, remain the gold standard.

Driving after Upper or Lower Extremity Orthopaedic Surgery

Orthopaedic procedures can affect patients' ability to perform activities of daily living, such as driving automobiles or other vehicles that require coordinated use of the upper and lower extremities. Many variables affect the time needed before a patient can drive competently after undergoing orthopaedic surgery to the extremities. These variables include whether the patient underwent upper or lower extremity surgery, the country in which the patient resides, whether the right or left lower extremity is involved, whether the dominant arm is involved, whether the extremity is in a cast or brace, whether the patient has adequate strength to control the steering wheel, and whether the patient is taking pain medication. The type and complexity of the procedure also influence the speed of return of driving ability. Few studies provide definitive data on driving ability after upper or lower extremity surgery. Patients should be counseled not to drive until they can control the steering wheel and the pedals competently and can drive well enough to prevent further harm to themselves or to others. This review discusses the limited recommendations in the literature regarding driving motorized vehicles after upper or lower extremity orthopaedic surgery.

Reaction Time and Brake Pedal Depression Following Arthroscopic Hip Surgery: A Prospective Case-Control Study

PURPOSE

The purpose of this study was to determine whether patients diagnosed with femoroacetabular impingement (FAI) syndrome have prolonged braking times compared with age- and gender-matched controls and how long after surgery braking times return to preoperative baseline.

METHODS

Fifty-nine patients undergoing arthroscopic hip surgery for FAI and 59 age- and gender-matched controls without FAI were enrolled in a prospective comparative study between September 2015 and October 2016. Total brake reaction time (BRT) and brake pedal depression (BPD) were measured for study patients preoperatively, and at 2, 4, and 6 weeks postoperatively. BRT and BPD were compared between study and control patients and between preoperative and postoperative time periods, using mixed effects models.

RESULTS

Patients with FAI had significantly prolonged BRT (but not BPD) prior to surgery compared with controls (568 vs 520 msec, P = .002). For study patients undergoing left hip surgery, there was no difference in BRT or BPD between preoperative measurements and any postoperative time point, including the first postoperative appointment at 2 weeks (563 vs 566 msec, P = .89). Patients undergoing right hip surgery had significantly prolonged BRT at 2 weeks postoperatively compared with their preoperative baseline (688 vs 573 msec, P < .001). By 4 weeks postoperatively, study patients undergoing right hip surgery had returned to their preoperative baseline (573 vs 594 msec, P = .28). No significant effect was seen based on visual analog scale pain score, opiate usage, or patient-reported outcome scores.

CONCLUSIONS

Patients undergoing arthroscopic surgery of the right hip show significantly prolonged BRT until 4 weeks after surgery, while patients undergoing surgery of the left hip show no postoperative impairment in either BRT or BPD. The clinical relevance of this measured difference (an increase in 10 feet of stopping distance at 60 miles per hour) remains an open question.

LEVEL OF EVIDENCE

Level II, diagnostic, prospective.

Driving ability after right-sided puncture of the common femoral artery during coronary angiography

Objectives/background

To assess brake reaction time (BRT; key factor in driving ability) in patients receiving transfemoral coronary angiography (CAG). We assumed that patients would have a significantly impaired BRT after the procedure.

Methods

A prospective, observational study design was applied. Consecutive patients undergoing right-sided transfemoral CAG as part of the clinical routine were included. An experimental driving simulator was used to determine BRT after receiving a visual stimulus. The subjects applied the brake with their right foot as quickly as possible when a red-light signal appeared. The time interval between stimulus and brake application was taken as BRT. In addition to the total BRT, also its components were determined: neurologic reaction time, foot transfer time and brake travel time. BRT was determined before and 1 day after CAG (pre-post comparison).

Results

71 patients were included in the analysis (58 male, age 61 ± 9 years). Total BRT was 594 ± 188 and 591 ± 198 ms before and after the CAG procedure, respectively (p = 0.270). Similarly, also the BRT components ‘foot transfer time’ and ‘brake travel time’ did not show significant differences between the two test occasions. However, neurologic reaction time decreased from 269 ± 67 to 255 ± 64 ms (p = 0.036).

Conclusions

We found no impairment of BRT on the first day after puncture of the right-sided femoral artery in patients undergoing CAG. Therefore, with regard to BRT, it is regarded safe to resume driving from day 1 after CAG. Other factors of driving safety beyond BRT must also be considered.

Braking Time Following Total Knee Arthroplasty: A Systematic Review

BACKGROUND

Currently, no guidelines exist to assist surgeons in providing recommendations to patients undergoing total knee arthroplasty (TKA) on when it is safe to return to driving. The purpose of this systematic review is to analyze the best available literature to assist surgeons in providing evidence-based recommendations on when it is safe to return to driving after TKA.

METHODS

Following established methodology for the conduct of systematic reviews, a literature search was performed for prospective studies on driving after TKA. Two reviewers screened citations for inclusion, assessed methodological quality, and extracted data.

RESULTS

Nine studies with 330 subjects met the inclusion criteria. Normalization of brake response time, movement time, and reaction time to preoperative baseline was assessed by pooling data across studies between 0 and 4 weeks and >4 weeks after TKA. Patients who underwent left TKA and right TKA showed normalization by 2 and 4 weeks, respectively. The limited studies that evaluated brake response time, movement time, and reaction time prior to 2 weeks postoperatively also showed normalization to preoperative levels.

CONCLUSION

Patients with right TKA have normalization of braking time by 4 weeks, and normalization is as early as 2 weeks following left TKA. Surgeons must consider these recommendations and other patient factors that determine fitness to drive prior to deeming a patient safe to return to driving.

When is it safe to resume driving after total hip and total knee arthroplasty? a meta-analysis of literature on post-operative brake reaction times

AIMS

The aim of this study was to assess the current available evidence about when patients might resume driving after elective, primary total hip (THA) or total knee arthroplasty (TKA) undertaken for osteoarthritis (OA).

MATERIALS AND METHODS

In February 2016, EMBASE, MEDLINE, Web of Science, Scopus, Cochrane, PubMed Publisher, CINAHL, EBSCO and Google Scholar were searched for clinical studies reporting on 'THA', 'TKA', 'car driving', 'reaction time' and 'brake response time'. Two researchers (CAV and JJT) independently screened the titles and abstracts for eligibility and assessed the risk of bias. Both fixed and random effects were used to pool data and calculate mean differences (MD) and 95% confidence intervals (CI) between pre- and post-operative total brake response time (TBRT).

RESULTS

A total of 19 studies were included. The assessment of the risk of bias showed that one study was at high risk, six studies at moderate risk and 12 studies at low risk. Meta-analysis of TBRT showed a MD decrease of 25.54 ms (95% CI -32.02 to 83.09) two weeks after right-sided THA, and of 18.19 ms (95% CI -6.13 to 42.50) four weeks after a right-sided TKA, when compared with the pre-operative value.

CONCLUSION

The TBRT returned to baseline two weeks after a right-sided THA and four weeks after a right-sided TKA. These results may serve as guidelines for orthopaedic surgeons when advising patients when to resume driving. However, the advice should be individualised. Cite this article: Bone Joint J 2017;99-B:566-76.

Driving After Microinvasive Total Hip Arthroplasty

BACKGROUND

Patients undergoing total hip arthroplasty (THA) are often advised to avoid driving for 6 weeks postoperation. This is based on patients having to maintain postoperative hip precautions and studies investigating brake reaction time (BRT) following THA using conventional techniques. The aim of this study was to assess patients' ability to drive in the early postoperative period following microinvasive THA by assessing BRT.

METHODS

Hundred consecutive patients undergoing SuperPATH^® THA in 2015 who drove automobiles preoperatively were included in this prospective cohort study. BRT was measured preoperatively and at day 1 or 2 postoperation using a driving simulator. A subset of 25 consecutive patients had repeat BRT testing at 2 weeks postoperation. Five BRT measures were taken at each time point. Differences in the patient's mean and best BRT at each time point were assessed using the paired t-test.

RESULTS

The study cohort included 50 men and 50 women with mean age 63 years (range 25-86). The mean preoperative BRT was 0.63 s (range 0.43-1.44), with a mean difference of -0.1 s (range -0.57 to 0.33, P < .0001) at day 1 or 2 postoperation. The 2-week mean and best BRTs were also better than paired preoperative readings with a mean improvement of 0.15 s (range -0.78 to -0.004, P < .0001).

CONCLUSION

BRT reaches preoperative values by day 2 following microinvasive THA. Patients may be suitable to drive earlier than the previously recommended 6 weeks postoperation.

When Can I Drive After Orthopaedic Surgery? A Systematic Review

BACKGROUND

Patients often ask their doctors when they can safely return to driving after orthopaedic injuries and procedures, but the data regarding this topic are diverse and sometimes conflicting. Some studies provide observer-reported outcome measures, such as brake response time or simulators, to estimate when patients can safely resume driving after surgery, and patient survey data describing when patients report a return to driving, but they do not all agree. We performed a systematic review and quality appraisal for available data regarding when patients are safe to resume driving after common orthopaedic surgeries and injuries affecting the ability to drive.

QUESTIONS/PURPOSES

Based on the available evidence, we sought to determine when patients can safely return to driving after (1) lower extremity orthopaedic surgery and injuries; (2) upper extremity orthopaedic surgery and injuries; and (3) spine surgery.

METHODS

A search was performed using PubMed and EMBASE^®, with a list of 20 common orthopaedic procedures and the words "driving" and "brake". Selection criteria included any article that evaluated driver safety or time to driving after major orthopaedic surgery or immobilization using observer-reported outcome measures or survey data. A total of 446 articles were identified from the initial search, 48 of which met inclusion criteria; abstract-only publications and non-English-language articles were not included. The evidence base includes data for driving safety on foot, ankle, spine, and leg injuries, knee and shoulder arthroscopy, hip and knee arthroplasty, carpal tunnel surgery, and extremity immobilization. Thirty-four of the articles used observer-reported outcome measures such as total brake time, brake response time, driving simulator, and standardized driving track results, whereas the remaining 14 used survey data.

RESULTS

Observer-reported outcome measures of total brake time, brake response time, and brake force postoperatively suggested patients reached presurgical norms 4 weeks after right-sided procedures such as TKA, THA, and ACL reconstruction and approximately 1 week after left-sided TKA and THA. The collected survey data suggest patients resumed driving 1 month after right-sided and left-sided TKAs. Patients who had THA reported returning to driving between 6 days and 3 months postoperatively. Observer-reported outcome measures showed that patients' driving abilities often are impaired when wearing an immobilizing cast above or below the elbow or a shoulder sling on their dominant arm. Patients reported a return to driving on average 2 months after rotator cuff repair procedures and approximately 1-3 months postoperatively for total shoulder arthroplasties. Most patients with spine surgery had normal brake response times at the time of hospital discharge. Patients reported driving 6 weeks after total disc arthroplasty and anterior cervical discectomy and fusion procedures.

CONCLUSIONS

The available evidence provides a best-case scenario for when patients can return to driving. It is important for observer-reported outcome measures to have normalized before a patient can consider driving, but other factors such as strength, ROM, and use of opioid analgesics need to be considered. This review can provide a guideline for when physicians can begin to consider evaluating these other factors and discussing a return to driving with patients. Survey data suggest that patients are returning to driving before observer-reported outcome measures have normalized, indicating that physicians should tell patients to wait longer before driving. Further research is needed to correlate observer-reported outcome measures with adverse events, such as motor vehicle accidents, and clinical tests that can be performed in the office.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Changes in Driving Performance Following Shoulder Arthroplasty

BACKGROUND

With this study, we sought to quantify perioperative changes in driving performance among patients who underwent anatomic or reverse shoulder arthroplasty.

METHODS

Using a driving simulator, 30 patients (20 anatomic and 10 reverse total shoulder arthroplasties) were tested preoperatively and at 2 weeks (PO2), 6 weeks (PO6), and 12 weeks (PO12) postoperatively. The total number of collisions, centerline crossings, and off-road excursions (when the vehicle traversed the lateral road edge), and scores on a visual analog scale (VAS) for pain and the Shoulder Pain and Disability Index (SPADI) were recorded at each driving trial.

RESULTS

The mean number of collisions increased from 5.9 preoperatively to 7.4 at PO2 and subsequently decreased to 5.6 at PO6 and 4.0 at PO12 (p = 0.0149). In addition, the number of centerline crossings decreased from 21.4 preoperatively to 16.3 at PO12 (p < 0.05). Multivariate analysis of the data demonstrated that increased VAS for pain scores, older age, and less driving experience had a negative impact on driving performance.

CONCLUSIONS

Driving performance returned to preoperative levels at 6 weeks after shoulder arthroplasty. By 12 weeks postoperatively, patients demonstrated improved driving performance compared with preoperative performance. On the basis of our findings, clinicians can suggest a window of 6 to 12 weeks postoperatively for the gradual return to driving. However, for patients of older age, with less driving experience, or with greater pain, a return to driving at closer to 12 weeks postoperatively should be recommended.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Driving abstinence is necessary after lumbar spinal fusion: a prospective cohort study

PURPOSE

Studies on driving safety after lumbar spinal procedures are rare. Previous studies solely reported on a) driving reaction time (DRT) after lumbar nerve root blocks, b) DRT after discectomy and c) preliminary DRT findings after lumbar fusion.

METHODS

DRT was assessed with a driving simulator as described before. Measurements were done one day before surgery (preop DRT), one week after surgery (postop1 DRT), three months (postop2 DRT) and one year postoperatively (postop3 DRT). Back pain was determined with visual analogue scales (VAS) on all four occasions. Additionally, we monitored each patient's pre-operative driving frequency and intake of analgesics. For statistical analysis we used an ANOVA for repeated measurements.

RESULTS

Thirt eight of 51 patients completed all measurements (17 monosegmental fusion, 14 polysegmental fusion, seven other lumbar fusion procedures). The longitudinal changes in DRT showed overall significance (p = 0.013). Post-hoc tests determined p = 0.035 for the DRT-increase from pre- to postoperative. We did not determine a significant statistical effect for the type of surgery (p = 0.581) or patient age (p = 0.134). A tendency towards statistical significance was ascertained for the influence of patients' driving frequency on DRT (p = 0.051).

CONCLUSIONS

We found increased DRT at the time of discharge after lumbar spinal fusion and therefore recommend driving abstinence for the time thereafter. Based on our findings it appears safe to return to driving at 3 months postoperative.

Typical Brake Reaction Times Across the Life Span

This paper provides average brake reaction times for healthy community living adults from 16 to 90+ years of age, divided by gender. Using consistent directions and context, the RT-2S Simple Brake Reaction shows that average brake reactions for males is 0.50 seconds (median = 0.48, minimum = 0.25 maximum = 0.92) and for females is 0.53 seconds (median = 0.51 minimum = 0.30 maximum = 1.36). The use of a brake reaction timer to assess fitness to drive may be useful for clients recovering from orthopedic surgery, while use as a driving determinate of older adults should be done in conjunction with other tools.

When Is It Safe to Return to Driving After Spinal Surgery?

Study Design Prospective study. Objective Surgeons' recommendations for a safe return to driving following cervical and lumbar surgery vary and are based on empirical data. Driver reaction time (DRT) is an objective measure of the ability to drive safely. There are limited data about the effect of cervical and lumbar surgery on DRT. The purpose of our study was to use the DRT to determine when the patients undergoing a spinal surgery may safely return to driving. Methods We tested 37 patients' DRT using computer software. Twenty-three patients (mean 50.5 ± 17.7 years) received lumbar surgery, and 14 patients had cervical surgery (mean 56.7 ± 10.9 years). Patients were compared with 14 healthy male controls (mean 32 ± 5.19 years). The patients having cervical surgery were subdivided into the anterior versus posterior approach and myelopathic versus nonmyelopathic groups. Patients having lumbar spinal surgery were subdivided by decompression versus fusion with or without decompression and single-level versus multilevel surgery. The patients were tested preoperatively and at 2 to 3, 6, and 12 weeks following the surgery. The use of opioids was noted. Results Overall, the patients having cervical and lumbar surgery showed no significant differences between pre- and postoperative DRT (cervical p = 0.49, lumbar p = 0.196). Only the patients having single-level procedures had a significant improvement from a preoperative DRT of 0.951 seconds (standard deviation 0.255) to 0.794 seconds (standard deviation 0.152) at 2 to 3 weeks (p = 0.012). None of the other subgroups had a difference in the DRT. Conclusions Based on these findings, it may be acceptable to allow patients having a single-level lumbar fusion who are not taking opioids to return to driving as early as 2 weeks following the spinal surgery.

Driving and emergency braking may be impaired after tibiotalar joint arthrodesis: conclusions after a case series

PURPOSE

To assess whether reaction time (RT) and movement time (MT), as the two components of the total brake response time (TBRT) and brake force (BF) are different in patients with a foot joint arthrodesis in comparison to controls.

METHODS

The study was a comparative case series in a driving simulator under realistic driving conditions. Mobile patients without a walker, ≥6 months after surgery who were driving a car and had no neurological co-morbidity, knee or hip joint prosthesis were included in the study. The selection criteria resulted in 12 patients with right tibiotalar joint arthrodesis (TTJA) and 12 patients with another right foot joint arthrodesis (OFJA), who were compared to 17 individuals without any ankle-joint pathology. For TBRT, an empirical safe driving threshold of 700 ms was used. The outcome measures were RT, MT, TBRT, BF and McGuire score.

RESULTS

MT (p = 0.034) and TBRT (p = 0.026) were longer in TTJA patients in comparison with the controls. Also, more patients with TTJA than patients with OFJA and controls exceeded the safe driving threshold (p = 0.028). The outcomes in OFJA patients and in controls were comparable. The McGuire score was similar between the TTJA and OFJA patients (p = 0.26).

CONCLUSIONS

Significantly slower MT and TBRT, and significantly more patients exceeding the safe driving threshold, were observed after a tibiotalar-joint arthrodesis in comparison to the controls. Patients with OFJAs were not significantly different from the controls. Driving and emergency braking may be impaired after tibiotalar-joint arthrodesis.

Effects of Right Lower Limb Orthopedic Immobilization on Braking Function: An On-The-Road Experimental Study With Healthy Volunteers

Little is known about how immobilization of the right lower limb might affect driving. The purpose of the present study was to evaluate the effect of 2 types of immobilization on the emergency braking time of healthy subjects during actual driving conditions. The emergency braking times of 14 healthy volunteers were assessed in a closed circuit under 3 conditions: wearing running shoes, wearing an Aircast Walker(®), or wearing a walking cast on their right lower limb. An instrumented car was used to measure the emergency braking times during braking tests with and without a distractor. The foot movement times were significantly increased with both immobilization devices compared with the running shoe (p < .01). The median total braking time with the running shoe during emergency braking without a distractor was 0.452 (interquartile range, 25th to 75th [IQR], 0.413 to 0.472) second. The results obtained with the Aircast Walker(®) or the walking cast were significantly longer (p < .01), at 0.480 (IQR, 0.431 to 0.537) second and 0.512 (IQR, 0.451 to 0.535) second, respectively. When a distractor was added, the total braking time with the running shoe, Aircast Walker(®), and walking cast was 0.489 (IQR, 0.429 to 0.575), 0.516 (IQR, 0.459 to 0.586), and 0.510 (IQR, 0.469 to 0.570) second, respectively, with no statistically significant differences among these 3 conditions. Wearing an immobilization device on the right lower limb minimally lengthens the emergency braking time in healthy drivers under actual driving conditions. Clinicians must nonetheless exercise caution when advising a driver wearing an orthopedic immobilization, because driving a motor vehicle is a complex psychomotor task that goes well beyond the emergency braking time.

EMG provides an earlier glimpse into the effects of cognitive distraction on brake motor response

A driver’s ability to quickly perceive and respond to hazards is critical for traffic safety. With limited cognitive resources, any added distractions are likely to increase response times. This study analyzed the effect of two cognitive distraction tasks, 1-back and countdown, on total brake-response time and its subcomponents: perception and leg movement times (n=6). Participants sat in a stationary vehicle and responded to a light stimulus by moving their foot from the accelerator to the brake pedal as quickly as possible. Electromyography (EMG) recordings of the lower leg muscle provided earlier detection of movement onset compared to accelerator pedal motion. Performing a cognitive task was found to increase perception and total brake-response time compared to the baseline condition. There were no significant differences observed in leg movement time while performing either of the distraction tasks versus the baseline. Implications for areas of improvement and future works are discussed.

Brake response time returns to the pre-surgical level 6 weeks after unicompartmental knee arthroplasty

PURPOSE

The objective of the study was to clarify whether driving abstinence should be recommended when patients are discharged from hospital after unicompartmental knee arthroplasty (UKA). We tested the hypotheses that there are differences in the peri-operative course of brake response time in patients undergoing right-sided (1) or left-sided (2) UKA. Additionally, we tested whether brake response time is significantly influenced by pain (3), driving experience (4) or age (5).

METHODS

In 43 patients undergoing UKA, brake response time was measured with a custom-made driving simulator pre-operatively and 1 and 6 weeks after UKA. Patients' visual analogue scales for knee pain and their self-reported driving experience were also assessed.

RESULTS

In patients with right-sided UKA, brake response time changed from 786 (261) ms pre-operatively to 900 (430) ms 1 week post-operatively (p = 0.029). At 6 weeks post-operatively, brake response time had returned to 712 (139) ms, which was deemed to be an insignificant change from the pre-operative reference benchmark. When surgery was performed on the contralateral left side, no effect was found onto the right side's brake response time. Knee pain and driving experience were significantly correlated with brake response time. No such correlations were found between brake response time and age.

CONCLUSIONS

On the basis of the current findings, it is concluded that brake response time returns to pre-operative levels 6 weeks after UKA surgery. Therefore, it is proposed that driving be abstained from for that period.

Timeframe for return to driving for patients with minimally invasive knee arthroplasty is associated with knee performance on functional tests

Background

This study hopes to establish the timeframe for a safe return to driving under different speed conditions for patients after minimally invasive total knee arthroplasty and further explores how well various kinds of functional tests on knee performance can predict the patients’ braking ability.

Methods

14 patients with right knee osteoarthritis were included in the present study and instructed to perform three simulated driving tasks at preoperative, 2 weeks postoperative and 4 weeks postoperative.

Results

The results showed that the total braking time at 4 week postoperative has attained the preoperative level at the driving speed 50 and 70 km/hr but not at the driving speed 90 km/hr. It had significantly improving in knee reaction time and maximum isometric force at 4 weeks postoperative. Besides, there was a moderate to high correlation between the scores of the step counts and the total braking time.

Conclusions

Summary, it is recommended that driving may be resumed 4 weeks after a right knee replacement but had to drive at low or moderate speed and the best predictor of safety driving is step counts.

Influence of left- and right-side total hip arthroplasty on the ability to perform an emergency stop while driving a car

OBJECTIVE

To show the possible effect of left- and right-side total hip arthroplasty (THA) on the ability to perform an emergency stop when driving a car.

DESIGN

Inception cohort.

SETTING

A driving simulator using an actual car cabin, specifically developed for the experiment, was used for testing driving ability.

PARTICIPANTS

Patients (N=40; 20 left-side THA/20 right-side THA) were tested preoperatively and in increments of 8 days and 6, 12, and 52 weeks after surgery.

INTERVENTIONS

Left- and right-side THA.

MAIN OUTCOME MEASURES

Reaction time, movement time, total brake response time (TBRT), and maximum brake force.

RESULTS

Eight days postoperatively, measurements on driving performance indicated a slight worsening for all outcome parameters in patients after left-side THA and considerably more worsening in patients after right-side THA. For both patient groups, significant improvements in outcome measures were noted during the 1-year follow-up. Brake force declined significantly in patients with left-side THA (P=.012) and in patients after right-side THA (P<.001). A total of 35% of the patients with right-side THA and 15% with left-side THA could not meet the 600 ms TBRT threshold 6 weeks postoperatively.

CONCLUSIONS

Most patients who underwent right-side THA reached their preoperative baseline 6 weeks after surgery. Most of the patients with left-side THA showed no TBRT limitations 8 days postoperatively. Because of the patients' highly individual rehabilitation course and considering the possible consequences of the premature resumption of driving a motor vehicle, individual examination and recommendation are necessary.

Osteoarthritis of the knee or hip significantly impairs driving ability (cross-sectional survey)

Background

Advising patients about when they can drive after surgery is common practice after arthroplasty of the knee or hip. In the literature, the preoperative braking performance values of the patients are frequently taken as the “safe” landmark. We hypothesised that osteoarthritis (OA), the most frequent reason for arthroplasty, already compromises the ability to perform an emergency stop. We expected that both Reaction Time (RT) and Movement Time (MT) as components of the Total Brake Response Time (TBRT), would be prolonged in patients with OA of the knee or hip in comparison with healthy subjects. We also expected maximum pressure levels on the brake pedal to be reduced in such cases.

Methods

A real car cabin was equipped with pressure sensors on the accelerator and brake pedals to measure RT, MT, TBRT and maximum Brake Force (BF) under realistic spatial constraints. Patients with OA of the knee (right n = 18, left n = 15) or hip (right n = 20, left n = 19) were compared with a healthy control group (n = 21).

Results

All measured values for TBRT in the control group remained below 600 ms. OA of the right hip or knee significantly prolonged the braking performance (right hip: TBRT p = 0.025, right knee: TBRT p < 0.001), whereas OA of the left hip did not impair driving ability (TBRT p = 0.228). Intriguingly, OA of the left knee prolonged RT and MT to the same degree as OA on the contralateral side (RT p = 0.001, MT p < 0.001).

Conclusions

This study demonstrates that depending on the localisation of OA, driving capability can be impaired; OA can significantly increase the total braking distance. To ensure safe traffic participation the safety margin for TBRT should be strictly set, under our experimental conditions, at around 600 ms. Moreover, therapeutic approaches to OA, such as physiotherapy, and patients receiving surgery of the left knee should take into account that left knee OA can also impair driving ability.

Trial registration

Clinical trial registration number: Project number of the ethics committee of the University of Tübingen: 268/2009BO2; 267/2009BO2.

Medical Aspects of Fitness to Drive

Orthopedic surgeons and other stakeholders need better return-to-driving guidelines for post–orthopedic surgery and trauma patients. The state of the current orthopedic research is in need of better methodology, particularly regarding control over the cognitive domain’s influence on the physical domain. Recommendations need to be based on an individual’s assessment of physical performance rather than the passage of time after surgery. This article highlights the areas of concern for driving research in the orthopedic community and how they can affect study design.

Driving after orthopaedic surgery

The decision to drive after orthopaedic injury or surgery is fraught with legal and safety issues. Although driving is an important part of most patients' lives, there are no well-established guidelines for determining when it is safe to drive after injury or treatment. Typically, impairment in driving ability is measured by changes in the time needed to perform an emergency stop. Braking function returns to normal 4 weeks after knee arthroscopy, 9 weeks after surgical management of ankle fracture, and 6 weeks after the initiation of weight bearing following major lower extremity fracture. Patients may safely drive 4 to 6 weeks after right total hip arthroplasty or total knee arthroplasty. Patients should not drive with a cast or brace on the right leg. Upper extremity immobilization may cause significant impairment if the elbow is immobilized; however, simple forearm casts may be permissible.

Driving after orthopedic surgery

As a result of reading this article, physicians should be able to: (1) Identify preoperative factors that may contribute to a patient's ability to return to driving after orthopedic surgery. (2) Understand the role of upper-extremity immobilization and how it may impair a patient's ability to operate a motor vehicle. (3) Recognize how various forms of lower-extremity immobilization (e.g., controlled ankle-motion boot, cast, and Aircast Walker) affect braking reaction times and total braking times. (4) Be aware of current guidelines about when it is appropriate to return to driving following arthroscopy, lower-extremity fracture, and hip and knee arthroplasty. Few guidelines are available to assist orthopedic surgeons in advising patients about when to return to driving after orthopedic surgery. A patient's surgical procedure, postoperative weight-bearing restrictions, immobilization, and other factors influence a patient's ability to drive after orthopedic surgery. Multiple studies have used driving simulators to predict when it may be safe to return to driving after orthopedic surgery. However, study conclusions and recommendations vary significantly. This article reviews the factors contributing to a patient's ability to return to driving after orthopedic surgery and reviews recommendations based on the available literature following fracture, arthroscopy, and arthroplasty.

Driving reaction time before and after anterior cervical fusion for disc herniation: a preliminary study

PURPOSE

Reduced driving reaction time (DRT) has already been studied in context with lumbar disc surgeries. Data on whether cervical spine pathologies impair driving abilities are still lacking. In addition, no return-to-driving recommendations after anterior cervical fusion procedures have been published. Therefore, we assessed DRT before and after anterior cervical discectomy and fusion.

METHODS

We performed a prospective study with 12 patients (mean age 47.2 years; female 7, male 5). DRT as well as arm and neck pain were evaluated before surgery, on the day before discharge from hospital and at the 4-6-week follow-up examinations. 31 healthy subjects were tested for DRT as a control group.

RESULTS

All patients showed significant improvement in DRT in the longitudinal course (p < 0.05). DRT was 601 ms (median, IQR: 63) before surgery, which was reduced to 580 ms (median, IQR: 112) on the day before discharge from hospital and to 532 ms (median, IQR: 48) at follow-up examination. Control subjects had a driving reaction time of 487 ms (median, IQR: 116), which differed significantly from that of patients at all three testing times (p < 0.05). VAS for arm and neck pain showed significant improvement (p < 0.05).

CONCLUSION

The present results show a positive effect of anterior cervical discectomy and fusion on driving safety. Based on our data we state that it appears to be safe to resume driving after discharge from hospital. However, patients scheduled to undergo anterior cervical discectomy and fusion should be informed about increased DRT as compared to healthy individuals.

“When can I return to driving?”

Clinicians are often asked by patients, “When can I drive again?” after lower limb injury or surgery. This question is difficult to answer in the absence of any guidelines. This review aims to collate the currently available evidence and discuss the factors that influence the decision to allow a patient to return to driving. Medline, Web of Science, Scopus, and EMBASE were searched using the following terms: ‘brake reaction time’, ‘brake response time’, ‘braking force’, ‘brake pedal force’, ‘resume driving’, ‘rate of application of force’, ‘driving after injury’, ‘joint replacement and driving’, and ‘fracture and driving’. Of the relevant literature identified, most studies used the brake reaction time and total brake time as the outcome measures. Varying recovery periods were proposed based on the type and severity of injury or surgery. Surveys of the Driver and Vehicle Licensing Agency, the Police, insurance companies in the United Kingdom and Orthopaedic Surgeons offered a variety of opinions.

There is currently insufficient evidence for any authoritative body to determine fitness to drive. The lack of guidance could result in patients being withheld from driving for longer than is necessary, or returning to driving while still unsafe.

Cite this article: Bone Joint J 2013;95-B:290–4.

Driving following acute lower limb painful events

SUMMARY Orthopedic procedures or injuries can temporarily prevent patients from driving. The time duration until they can resume driving has significant financial, medico-legal and legal implications on the patient, physician and society. There are a few guidelines about driving restrictions following acute lower limb events, however, the time duration varies among jurisdictions. The current published recommendations vary from no driving abstinence to 9 weeks, depending on the affected side, procedure, immobilization, pain level and type of car (automatic vs manual). There is also individual variability in patients with respect to their pain, comorbidities and prior driving experience. The decision to allow a patient to drive is often made clinically by the treating physician, but there is no consensus among orthopedic surgeons about driving restrictions. The use of opioid analgesic medications is regarded as an important factor in the decision to restrict driving. In this article, we review the current guidelines and clinical studies available for acute lower limb injuries or interventions including total hip arthroplasties and total knee arthroplasties, knee arthroscopies, anterior cruciate ligament reconstruction and lower extremity fractures.

Driving reaction time before and after surgery for lumbar disc herniation in patients with radiculopathy

PURPOSE

Although patients scheduled to undergo lumbar disc surgery often ask when they are allowed to drive a motor vehicle again, there are no published recommendations on this subject.

METHODS

We conducted a prospective study in 46 consecutive patients (mean age 48.9 years) to determine driving reaction time (DRT) before and after surgery in patients with lumbar disc herniation. Of the patients 23 had left-side radiculopathy and 23 right-side radiculopathy. Driving reaction time as well as back and leg pain were evaluated preoperatively, on the day of discharge from hospital and at the 5-week follow-up examination (FU). 31 healthy subjects were tested as controls.

RESULTS

Significant improvement in DRT was seen for both patient samples (p < 0.05). For patients with a right-side radiculopathy preoperative DRT was 664 ms (median, IQR: 241), which was reduced to 605 ms (median, IQR: 189) immediately postoperatively and to 593 ms (median, IQR: 115) at FU. For patients with a left-side radiculopathy DRT was 675 ms (median, IQR: 247) preoperatively, 638 ms (median, IQR: 242) postoperatively and 619 ms (median, IQR: 162) at FU. Pain was moderately correlated to DRT. Control subjects had a driving reaction time of 487 (median, IQR: 116), which differed significantly from patients at all three testing times (p < 0.001).

CONCLUSION

Our data indicate a positive effect of the surgery on driving ability. Therefore, we would suggest that for both patient samples it is safe to continue driving after hospital discharge. However, patients have to be informed about increased DRT caused by radiculopathy already before surgery.

When can I drive?: brake response times after contemporary total knee arthroplasty

BACKGROUND

After right total knee arthroplasty (TKA), patients are usually eager to return to driving. Previous studies suggest 6 weeks postsurgery is a safe time. However, recent advances in surgical technique, pain management, and rehabilitation have theoretically improved recovery after TKA.

QUESTIONS/PURPOSES

We therefore determined if (1) the timeframe for return to driving, as determined by attainment of preoperative braking levels, would be shorter after contemporary right TKA than that reported previously for a traditional TKA; and (2) gender or age influence recovery of baseline response time.

METHODS

Brake response times for all 29 patients undergoing right-sided TKA between January 17, 2008, and January 29, 2009, were scheduled to be measured by a trained occupational therapist before surgery and at 4, 6, and 8 weeks after surgery. For each patient, testing was discontinued once the preoperative level was achieved.

RESULTS

All patients returned to baseline braking levels by 4 weeks after surgery. Gender and age did not influence recovery times.

CONCLUSIONS

If other requirements for driving are met, surgeons may consider allowing patients treated with contemporary right TKAs to drive 4 weeks after surgery.

Brake response time before and after total knee arthroplasty: a prospective cohort study

BACKGROUND

Although the numbers of total knee arthroplasty (TKA) are increasing, there is only a small number of studies investigating driving safety after TKA. The parameter 'Brake Response Time (BRT)' is one of the most important criteria for driving safety and was therefore chosen for investigation.The present study was conducted to test the hypotheses that patients with right- or left-sided TKA show a significant increase in BRT from pre-operative (pre-op, 1 day before surgery) to post-operative (post-op, 2 weeks post surgery), and a significant decrease in BRT from post-op to the follow-up investigation (FU, 8 weeks post surgery). Additionally, it was hypothesized that the BRT of patients after TKA is significantly higher than that of healthy controls.

METHODS

31 of 70 consecutive patients (mean age 65.7 +/- 10.2 years) receiving TKA were tested for their BRT pre-op, post-op and at FU. BRT was assessed using a custom-made driving simulator. We used normative BRT data from 31 healthy controls for comparison.

RESULTS

There were no significant increases between pre-op and post-op BRT values for patients who had undergone left- or right-sided TKA. Even the proportion of patients above a BRT threshold of 700 ms was not significantly increased postop. Controls had a BRT which was significantly better than the BRT of patients with right- or left-sided TKA at all three time points.

CONCLUSION

The present study showed a small and insignificant postoperative increase in the BRT of patients who had undergone right- or left-sided TKA. Therefore, we believe it is not justified to impair the patient's quality of social and occupational life post-surgery by imposing restrictions on driving motor vehicles beyond an interval of two weeks after surgery.

Method for quantifying patient expectations and early recovery after total knee arthroplasty

Many components of a surgeon's total knee arthroplasty (TKA) treatment regimen affect the rate of recovery, such as patient selection, preoperative education, surgical technique, pain management, and postoperative rehabilitation. Therefore, accurate counseling requires that the surgeon quantifies patient expectations and early recovery of the treatment regimen with a method that minimizes interviewer bias. Preoperatively and 4 to 5 weeks after TKA, 285 patients (306 consecutive primary TKAs) responded to a survey consisting of customized questions, the Oxford score, the SF-12, and Knee Society scores on a handheld data acquisition device. The average response to each question on the 4- to 5-week postoperative survey defined patient expectations, and the change in a response between the 4- to 5-week postoperative and the preoperative survey determined whether the surgical intervention improved the patient. At 4 to 5 weeks postoperatively, 80% of patients walked without a cane, 54% drove a car, 88% thought the treated knee was functioning better than before surgery, 93.5% thought the treated knee was normal or nearly normal, and 98% thought the alignment of their limb was "just right." By 4 to 5 weeks, patients experienced less pain and showed significant improvements in 11 of 12 activities queried by the Oxford score, SF-12 physical score, Knee function score, Knee Society score, and knee extension. Flexion was significantly less at 4 to 5 weeks, and the SF-12 mental score was not significantly different. Average hospital stay was 2 nights, with 98% discharged home. Surgeons should consider a method that minimizes interviewer bias to quantify patient expectations and rate of recovery of their specific treatment regimen, and then use this information to counsel their patients to avoid disappointment after TKA.