Brake reaction time before and after surgery for patients with sequestrectomy versus conventional microdiscectomy.

The aim of this study was to compare the effects of sequestrectomy versus conventional microdiscectomy on breaking response time (BRT) for lumbar disc herniation (LDH). BRT is the key factor for return to drive recommendations after surgery. A prospective clinical study was conducted. Patients aged 25-65 years who underwent surgery for lumbar disc herniation and held a valid motorcar driving license were recruited in a single institution. The patients were assessed before surgery, immediately after the surgery and at the follow up examination 30 days post-surgery. BRT was measured using a driving simulator, a visual analogue scale (VAS) was used for pain assessment. BRT values were compared with BRT values of a healthy control group. In patients treated with microdiscectomy BRT reduced from 749 (±223) msec before surgery to 649 (±223) msec immediately after the surgery. In the sequestrectomy group BRT reduced from 852 (±561) msec before surgery to 693 (±173) msec immediately after the surgery. BRT at follow up was 610 (±145) msec for patients treated with microdiscectomy and 630 (±98) msec for patients operated with sequestrectomy. BRT for healthy controls was 487 (±116) msec. Pain improved significantly for both patient samples. Sequestrectomy and microdiscectomy were associated with similar effects on pain and BRT after surgery. There was no statistically significant difference between BRT of both patient samples at 30 days follow up examination. Both surgical techniques showed a positive effect on BRT. No statistically significant difference between sequestrectomy and microdiscectomy on BRT could be found.

Is it safe to drive after oral surgery?

OBJECTIVES: Driving ability largely depends on the total brake response time (TBRT) corresponding to the time a subject needs to react to a stimulus and apply a well-defined force on the brake pedal. As yet, the English literature completely lacks clinical studies evaluating the TBRT following oral surgery. MATERIALS AND METHODS: In this case-control study, a driving simulator was used to evaluate the TBRT in patients scheduled for oral surgery in local anesthesia. Measurements were taken shortly before (t1) and after (t2) surgery as well as 7-10 days later (t3) when sutures were removed. Results were compared to data of a group of healthy volunteers. RESULTS: Seventy-three patients (37 women, 36 men) underwent evaluation at t1, t2, and t3. In 13 patients who did not return for removal of sutures, only measurements at t1 and t2 could be performed. The median TBRT was 583 milliseconds (ms), 634 ms, and 520 ms at t1, t2, and t3, respectively. Statistical analysis revealed significant differences between readings at t1 versus t2 (t = - 4.944, p < 0.001), t1 versus t3 (t = 7.454, p < 0.001), and t2 versus t3 (t = 11.971, p < 0.001). There was no significant difference between TBRT at t3 in study subjects compared to normal reference values of 67 healthy volunteers. TBRT was significantly increased immediately after oral surgery (t2) compared to measurements 7-10 days postoperatively (t3). Since readings at t3 did not differ from TBRT values in the comparison group, they were considered normal. CONCLUSIONS: Due to significantly elevated total brake response time, driving ability is assumed to be considerably affected following oral surgery, and patients should be advised to abstain from driving immediately after such operations. CLINICAL RELEVANCE: Our study results put into question patients' driving ability following dentoalveolar procedures which should be considered regarding informed consent and could potentially have consequences on health issues (road traffic accidents) as well as legal and financial matters (court charges, insurance claims).

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.

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.

Effect of hip braces on brake response time: Repeated measures designed study.

BACKGROUND: The question whether or not a patient with a hip brace should drive a car is of obvious importance because the advice given to patients to resume driving is often anecdotal as few scientific data are available on this specific subject. OBJECTIVES: To assess driving ability (brake response time) with commonly used hip braces. STUDY DESIGN: Repeated measures design. METHODS: Brake response time was assessed under six conditions: (1) without a brace (control), (2) with a typical postoperative hip brace with adjustable range of motion and the settings: unrestricted, (3) flexion limited to 70°, (4) extension blocked at 20° hip flexion, (5) both flexion and extension limited (20°/70°) and (6) an elastic hip bandage. Brake response time was assessed using a custom-made driving simulator as used in previous studies. The participants were a convenience sample of able-bodied participants. RESULTS: A total of 70 participants (35 women and 35 men) participated in our study. Mean age was 31.1 (standard deviation: 10.6; range: 21.7-66.4) years. A significant within-subject effect for brake response time was found ( p = 0.009), but subsequent post hoc analyses revealed no significant differences between control and the other settings. CONCLUSION: Based on our findings, it does not seem mandatory to recommend driving abstinence for patients wearing a hip orthosis. We suggest that our results be interpreted with caution, because (1) an underlying pathological hip condition needs to be considered, (2) the ability to drive a car safely is multifactorial and brake response time is only one component thereof and (3) brake response time measurements were performed only with healthy participants. Clinical relevance Hip braces are used in the context of joint-preserving and prosthetic surgery of the hip. Therefore, clinicians are confronted with the question whether to allow driving a car with the respective hip brace or not. Our data suggest that hip braces do not impair brake response time.

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.

Effect of surgical shoes on brake response time after first metatarsal osteotomy--a prospective cohort study.

BACKGROUND: The aim of this study is to assess patients' driving ability when wearing surgical shoes following right-sided first metatarsal osteotomy. METHODS: From August 2013 to August 2015, 42 consecutive patients (mean age 54.5 years) with right-sided hallux valgus deformity underwent first metatarsal osteotomy. Patients were tested for brake response time (BRT) 1 day preoperatively (control run) and at 2 and 6 weeks postoperatively. Two different types of foot orthosis were investigated. BRT was assessed using a custom-made driving simulator. RESULTS: Preoperative BRT was 712 msec (standard deviation (SD), 221 msec). BRT was significantly slower at all tested postoperative times than preoperatively (p < 0.001). The patients showed significant impaired brake response time when wearing surgical shoes. Mean global American Orthopaedic Foot and Ankle Society (AOFAS) outcome score and AOFAS pain and alignment subscores increased postoperatively (p < 0.001). CONCLUSIONS: From our findings, we recommend driving abstinence for a minimum of 6 weeks postoperatively when using a surgical shoe after bunionectomy. However, patients should have sufficient recovery, exercise, and training before resuming driving a car, because safety is always a priority. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02354066.

Driving ability after right-sided ankle arthroscopy--A prospective Study.

INTRODUCTION: Due to the current lack of evidence the aim of this study was to investigate the driving ability after right-sided ankle arthroscopy. MATERIALS AND METHODS: Nineteen patients underwent right-sided ankle arthroscopy. Brake response time (BRT) was assessed preoperatively, 2 days, 2 weeks, 6 weeks, and 12 weeks postoperative. We also determined patients' clinical outcome (AOFAS and AOS questionnaires) and their driving frequency. RESULTS: BRT was 606ms preoperatively and changed to 821ms 2 days postoperative (p<0.001). The further postoperative BRT course was 606ms (2 weeks), 596ms (6 weeks) and 603ms (12 weeks) (p=n.s.). In addition, a significant influence of the AOS and AOFAS scores on BRT was found, namely poorer clinical outcome also leads to a prolonged BRT (p<0.01 for both). BRT was significantly prolonged in patients with little driving frequency (p=0.001). Furthermore, the 'time-by-driving interaction' was significant (p=0.018), which means the BRT-peak on the second day was much lower in low-frequency drivers. CONCLUSIONS: From the findings made in the current study we conclude that a driving abstinence of two weeks is necessary following right-sided ankle arthroscopy. Greater driving frequency and good clinical outcome seem to be associated with better driving ability. However, for the time being no exceptions should be made from the above-mentioned recommendation on driving abstinence.

The effect of ankle brace type on braking response time-A randomised study.

INTRODUCTION: The question whether or not a patient with an ankle brace should drive a car is of obvious importance because brake response time (BRT) is considered one of the most important factors for driving safety. MATERIALS AND METHODS: Applying a crossover study design, 70 healthy participants (35 women, 35 men) participated in our study. BRT was assessed using a custom-made driving simulator. We assessed BRT under six conditions: without a brace (control) (1), with a typical postoperative ankle brace with adjustable ROM and the settings: unrestricted (2), fixed at 15° (3) plantar flexion, restricted with 15°/50° (4) (dorsal/plantar flexion), a brace for ligament instabilities (5) and an elastic ankle bandage (6). Participants were instructed to apply the brake pedal exclusively with the right foot as quickly as possible on receipt of a visual stimulus. RESULTS: The 70 participants showed significantly impaired BRT with the ankle brace for ROM restriction in the settings: unrestricted (p<0.001), fixed at 15° plantar flexion (p<0.001) and 15°/50° dorsal/plantar flexion (p<0.001) as compared to the control group. BRT was not impaired with the brace for ankle instabilities or the elastic ankle bandage. CONCLUSIONS: In conclusion, right-sided ROM restricting ankle braces involve significant impairment of BRT in healthy participants. No such prolonged BRT was found for an elastic ankle bandage or the ligament brace.

Potential Mechanisms Leading to Overuse Injuries of the Back in Alpine Ski Racing: A Descriptive Biomechanical Study.

BACKGROUND: Overuse injuries of the back are a common complaint among top athletes and of competitive alpine skiers in particular. However, there is limited understanding about the sport-specific causes of these injuries that is essential for their prevention. PURPOSE/HYPOTHESIS: This study was undertaken to describe the sport-specific, overall trunk kinematics and skiers' loading during giant slalom turns and to assess the plausibility of the hypothesis that a combination of frontal bending, lateral bending, and/or torsion in the loaded trunk might be a potential mechanism leading to overuse injuries of the back in alpine ski racing. STUDY DESIGN: Descriptive laboratory study. METHODS: Eight European Cup-level athletes performed giant slalom runs with 2 different pairs of skis (varying in length, width, and sidecut). They were analyzed with respect to selected kinematic variables related to spinal disc loading. The overall trunk movement components (frontal bending, lateral bending, and torsion) were measured using 2 inertial measurement units fixed on the sacrum and sternum. Total ground-reaction forces were measured by pressure insoles. RESULTS: During the turn phase in which the total ground-reaction forces were the greatest (up to 2.89 times the body weight), the highest average values of frontal bending (38.7°), lateral bending (14.7°), and torsion (7.7°) in the trunk occurred. Similar magnitudes were observed when skiing on longer, giant slalom skis with less width and sidecut. CONCLUSION: The typical loading patterns of the back in alpine ski racing include a combined occurrence of frontal bending, lateral bending, and torsion in the loaded trunk. Because these factors are known to be related to high spinal disc loading, they may be considered important components of mechanisms leading to overuse injuries of the back in alpine ski racing. CLINICAL RELEVANCE: Prevention measures should aim to control and/or reduce the magnitude of frontal bending, lateral bending, and torsion in the trunk, as well as the peak loads, while skiing.

Effect of knee brace type on braking response time during automobile driving.

PURPOSE: To assess driving ability (brake response time [BRT]) with commonly used knee braces. METHODS: Sixty-four healthy participants (32 women and 32 men) participated in our study. BRT was assessed using a custom-made driving simulator. We assessed BRT for 5 different commonly used knee braces (right leg) used in 9 different settings: without a knee brace (control group); with a typical postoperative knee brace with adjustable range of motion (ROM) and the settings of 0° to 30°, 0° to 60°, 0° to 90°, and 20° to 90° (extension and flexion); and with an unloading knee brace for moderate to severe unicompartmental osteoarthritis, an orthosis for ligament instabilities, a knee brace for patellofemoral disorders, and an elastic knee bandage. RESULTS: The 64 participants (mean age, 33.5 years) showed significantly impaired BRT with the typical postoperative brace set at an ROM of 0° to 30° (673 milliseconds, P < .001), ROM of 0° to 60° (629 milliseconds, P < .001), ROM of 0° to 90° (607 milliseconds, P = .001), and ROM of 20° to 90° (602 milliseconds, P = .005) compared with the control group. However, no such impaired BRT was found for any other investigated knee brace. CONCLUSIONS: Right-sided ROM-restricting knee braces involve significant impairment of BRT in healthy participants. No such prolonged BRT was found for a patellofemoral realignment brace, a ligament brace, a valgus/osteoarthritis brace, or an elastic knee bandage. However, our findings should be viewed in light of the limitations of the study, which are (1) the lack of a defined decrease in BRT that could lead to an accident and (2) uncertainty of whether the statistical differences are also clinically important. LEVEL OF EVIDENCE: Level II, lesser-quality randomized controlled trial.

Driving reaction time before and after surgery for disc herniation in patients with preoperative paresis.

BACKGROUND CONTEXT: The effect of many types of surgeries on driving reaction time (DRT) has been reported. Although lumbar disc herniation is one of the most common spinal diseases, the effect on DRT has not been investigated. PURPOSE: To assess the effect of left- and right-sided pareses caused by lumbar disc herniation on DRT before and after surgery. STUDY DESIGN: Controlled prospective clinical trial. PATIENT SAMPLE: Patients undergoing disc surgery. OUTCOME MEASURES: Impact of paresis caused by lumbar disc herniation and disc surgery on DRT. METHODS: Forty-two consecutive patients (mean age, 50.3 years) were tested for DRT 1 day before surgery, postoperatively before hospital discharge, and 5 weeks after surgery. Visual analogue scale (VAS) for back and leg pain as well as pain medication and patients' driving frequency were recorded. RESULTS: Significant improvement of DRT after surgery was seen in patients with left- and right-sided pareses (p<.005). For the right-sided paresis group, the preoperative DRT was 761 ms (median, interquartile range [IQR]: 490), 711 ms (median, IQR: 210) immediately postoperatively, and 645 ms (median, IQR: 150) at follow-up (FU). For the left-sided paresis group, DRT was 651 ms (median, IQR: 270) preoperatively, 592 ms (median, IQR: 260) postoperatively, and 569 ms (median, IQR: 140) at FU. Significant differences between right- and left-sided pareses were identified preoperatively and at FU testing (p<.005). No correlation was found between VAS for leg or back pain and DRT. Historical control subjects had a DRT of 487 (median, IQR: 116), which differed significantly at all three test times (p<.001). CONCLUSIONS: A significant reduction in DRT in patients with right- and left-sided pareses was found after surgery, indicating a positive effect of surgery. The improvement in DRT seen immediately postoperatively and the lack of a generally accepted threshold for DRT would suggest that for both patient samples, it is safe to continue driving after hospital discharge. However, patients should be informed accordingly.

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.

Force transmission in offset broach handles used for hip replacement: comparison of three different designs.

In minimally invasive hip arthroplasty double offset broach handles are used, to facilitate the preparation of the femoral canal. The aim of this study was to quantify the differences in force and impulse transmission between two double offset broach handles and a single offset broach handle. Two double offset broach handles (A European version, B American version) were compared to a single offset broach handle. A surgical hammer was used to give a variable impact to the head of the broach handle. Thirty measurements for each of five falling heights were recorded for each broach handle. The force measured by a load cell connected to the broaches was used to obtain the maximum force peak and to calculate the impaction impulse. Normal data distribution was assumed and analysis of variances was performed. Results have demonstrated that the highest values of the force peak and force impulse were found in the single offset broach handle. Broach handle A had higher impulse values and lower maximum force values compared to broach handle B. The lateral lever arm has a measurable effect on the force transmission. In double offset broach handles less energy is transmitted to the tip. Surgeons have to be aware of the differences between the broach handles when using them intraoperatively.

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.

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.

Driving reaction time before and after primary fusion of the lumbar spine.

STUDY DESIGN: Controlled prospective study. OBJECTIVE: To determine whether driving reaction time (DRT) is influenced by primary lumbar fusion. SUMMARY OF BACKGROUND DATA: The effects of radiculopathy and nerve root blocks on DRT have been reported recently. To our knowledge, the relationship between lumbar fusion and DRT has not been previously studied although it is important for driving safety. The aim of the present study was to test the hypotheses that DRT after lumbar fusion is (1) altered after the operation, (2) influenced by pain, (3) influenced by the patient's driving skill, and (4) differs from the DRT of healthy controls. METHODS: Twenty-one consecutive patients (mean age, 53.5 years; SD 10.8) receiving primary lumbar fusion were tested for their DRT 1 day before surgery (preoperative), the day before discharge (postoperative) and 3 months after surgery (follow-up; FU). DRT was assessed using a custom-made driving simulator. The severity of back pain was determined on visual analogue scales separately for usual pain (VAS-U) and pain during testing (VAS-T). We also determined the patients' subjective driving frequency. Normative DRT data from 31 age-matched healthy controls were used for comparison. RESULTS: The preoperative DRT was 685 milliseconds (Md; IQR 246) and the postoperative DRT 728 milliseconds (Md; IQR 264), which was further reduced to 671 milliseconds (Md; IQR 202) after the FU period. Statistical significance was registered between postoperative and FU DRT (P = 0.007). Moderate to high correlations (0.537 < r < 0.680) were found between the VAS rating of back pain and DRT. Control subjects had a DRT of 487 milliseconds (Md; IQR 116), which differed significantly from the DRT of patients at all 3 time points of testing (P < 0.001). CONCLUSION: It appears safe to continue driving after discharge from the hospital following lumbar fusion. DRT improved significantly during FU, indicating a positive effect of the intervention on driving skills. DRT correlates with the severity of back pain.

Modified Prusik knot versus whipstitch technique for soft tissue fixation in anterior cruciate ligament reconstruction: a biomechanical analysis.

Appropriate graft tension and secure graft incorporation in bone tunnels are essential for successful anterior cruciate ligament (ACL) reconstruction using hamstring tendon autografts. Permanent viscoplastic elongation in response to cyclic loading in the early postoperative period and the interposition of suture material in the tendon-bone interface might negatively affect graft function and rigid graft incorporation in the bone tunnels. A modified Prusik knot is an alternative option to the commonly used whipstitch technique for soft tissue fixation in ACL reconstruction. This is a controlled laboratory study. Sixteen formalin-fixed human cadaver semitendinosus tendons were armed with a modified Prusik knot or a whipstitch and tested in a load-to-failure test with a constant displacement rate of 1 mm/s, 14 in the cyclic loading test with 100 cycles from 10 to 50 N followed by 100 cycles from 10 to 75 N. The modified Prusik knot showed smaller force-induced displacements and higher stiffness of the entire construct in the load-to-failure test. Smaller preconditioning displacements were the only significant differences in the cyclic loading test. The modified Prusik knot has equal or superior mechanical properties and provides a larger area in the tendon-bone interface without suture material compared with the whipstitch technique.

Is restoring regenerative potential a way to prevent anthracycline cardiotoxicity? A hypothesis.

Anthracycline-induced cardiotoxic effects are a serious problem among young patients who survive childhood cancer and there is an urgent need to avoid such effects. It is generally accepted that the only effective way to do this is to prevent cardiac injury during chemotherapy. There are several possible ways to do this, though questions remain. Evidence suggests the existence of a resident population of self-renewing cardiac stem cells capable of contributing to heart repair. Cardiac stem cells have an intrinsically poor regenerative response to heart injury. However, recent results point to ways to enhance the formation of cardiac precursor cells necessary for regeneration after injury. Moreover, the results of a recent study demonstrated that activation of the Notch signaling pathway, well characterized for its role in myogenesis and tissue formation during embryogenesis, restores impaired regenerative potential of skeletal muscle by activating resident precursor cells (satellite cells), which have a markedly impaired propensity to proliferate and to produce the myoblasts necessary for muscle regeneration. Based on these findings, and because the mechanisms behind the cardiotoxic effects of anthracyclines are not fully understood and current ways to avoid anthracycline-induced cardiotoxic effects have limitations, we hypothesize herein that an attractive way to avoid these effects may be to promote repair and regeneration, as opposed to prevent injury (e.g. by dexrazoxane).