Epidemiology of race day injury in young professional jockeys in Great Britain from 2007 to 2018: a retrospective cohort study.

INTRODUCTION: There are limited injury data in professional horse racing, particularly by sex. OBJECTIVES: To describe injury incidence, characteristics and falls in male and female, flat and jump jockeys in Great Britain. DESIGN AND SETTING: Retrospective cohort study of professional jockeys in Britain. PARTICIPANTS: 245 jockeys licensed between 2007 and 2017. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome measure was injury on a race day. Injury incidence (per 1000 rides; per 1000 falls) was derived. Incidence-rate ratios (IRR) were calculated to compare incidence between flat and jump racing, male and female jockeys, and male flat and male jump jockeys for: (i) injury incidence, (ii) fall incidence and (iii) injuries per fall. RESULTS: 234 British professional jockeys were included. Jockeys were on average 19.5±2.0 years old at licence date, 79.9% male and 58.1% flat. The time of follow-up (racing in the study) was 3.7 (SD=2.3) years. There were 278 injuries, occurring in-race (81.7%), in the stalls (10.8%) or parade ring (6.1%). After one injury was removed to preserve anonymity, 57.2% were soft tissue injuries, 25.3% fractures and 10.5% concussion. There were 1634 falls, with 92% in male jump racing. The injury incidence was higher in jump racing (5.1 vs 1.0/1000 jockey rides). The falls incidence was 1.8/1000 rides in flat and 46.2/1000 rides in jump racing (IRR 0.04, 95% CI 0.03 to 0.04). There were over five times higher injuries/1000 falls in flat than jump racing (IRR 5.56, 95% CI 4.05 to 7.53). Male flat jockeys fell less than female flat (IRR 0.57, 95% CI 0.35 to 0.97). CONCLUSION: Most injuries occurred in-race and were soft tissue injuries. Jump jockeys fell more often than flat, and female flat jockeys fell more often than male flat. Flat jockeys injured more frequently when falling. No sex differences were seen for injuries per fall.

CYP2B6*6 allele and age substantially reduce steady-state ketamine clearance in chronic pain patients: impact on adverse effects.

AIMS: Ketamine analgesia is limited by low intrinsic efficacy compounded by large interindividual variability in drug responses, possibly due to the heterogeneity in drug concentration. The CYP2B6*6 allele is associated with substantially reduced ketamine metabolism in vitro and, therefore, may affect ketamine clearance. Our aims were to examine the impact of the CYP2B6*6 allele on ketamine plasma clearance and on adverse effects in chronic pain patients. METHODS: CYP2B6 genotypes were identified in 49 chronic pain patients who received 24 h continuous subcutaneous infusions of ketamine. Steady-state plasma concentrations of ketamine (Css,k ) and norketamine (Css,nk ) were determined using HPLC. RESULTS: The median plasma clearance of ketamine after 100 mg 24 h(-1) dose was significantly lower in patients with the CYP2B6*6/*6 (21.6 l h(-1) ) and CYP2B6*1/*6 (40.6 l h(-1) ) genotypes compared with patients with the CYP2B6*1/*1 genotype (68.1 l h(-1) , P < 0.001). The ketamine : norketamine plasma metabolic ratio was significantly higher in patients with the CYP2B6*6/*6 genotype than in those with the CYP2B6*1/*6 and the CYP2B6*1/*1 genotypes (P < 0.001). Patients who experienced adverse effects had lower plasma clearance (45.6 l h(-1) ) than those who did not (52.6 l h(-1) , P = 0.04). The CYP2B6*6 genotype and age, and their combined impact explained 40%, 30% and 60% of the variation in Css,k , respectively. Similar results were observed after higher doses. CONCLUSIONS: The CYP2B6*6 allele is associated with a substantial decrease in steady-state ketamine plasma clearance in chronic pain patients. The decreased clearance and resultant higher plasma concentrations may be associated with a higher incidence of ketamine adverse effects.

Bilateral open thoracic cordotomy for refractory cancer pain: a neglected technique?

At least 10% of patients with cancer have pain that is refractory to systemic analgesics. For most of these patients, interventional techniques may be of benefit but are often not considered or are difficult to access. Of these techniques, spinal analgesia is most commonly used in Australia and the United Kingdom, and neurosurgical procedures, such as open cordotomy with sectioning of the spinothalamic tract, are rarely used. We describe a case illustrating the successful use of bilateral open thoracic cordotomy in a patient with refractory mixed nociceptive and neuropathic pain secondary to a lumbosacral tumor. We discuss the various interventional options and review the recent literature regarding the use of both percutaneous and open cordotomy for cancer pain.