Basketball vs. Hockey-The Changing Face of Sport-Related Injuries in Canada.

OBJECTIVE: To characterize and compare the incidence of basketball-related, soccer-related, and hockey-related injuries over a 10-year period. DESIGN: Cohort analysis of sport-related injuries using multiple Ontario healthcare databases. SETTING: Emergency department visits in Ontario, Canada. PATIENTS: Any patient who sustained musculoskeletal injuries sustained while playing basketball, soccer, or hockey between 2006 and 2017 were identified. ASSESSMENT OF RISK FACTORS: Sport of injury, age, sex, rurality index, marginalization status, and comorbidity score. MAIN OUTCOME MEASURES: Annual Incidence Density Rates of injury were calculated for each sport, and significance of trends was analyzed by assessing overlap of 95% confidence intervals. RESULTS: One lakhs eighty five thousand eighty hundred sixty-eight patients (median age: 16 years, interquartile range 13-26) received treatment for sport-related injuries (basketball = 55 468; soccer = 67 021; and hockey = 63 379). The incidence of basketball-related and soccer-related injuries increased from 3.4 (3.3-3.5) to 5.6 (5.5-5.7) and 4.4 (4.3-4.5) to 4.9 (4.8-5) per 10 000 person years, respectively, whereas the incidence of hockey-related injuries decreased from 4.7 (4.6-4.8) to 3.7 (3.6-3.8). Patients with basketball injuries were more marginalized (3.01 ± 0.74) compared with patients with soccer and hockey injuries (2.90 ± 0.75 and 2.72 ± 0.69, respectively). CONCLUSIONS: Accurate regional epidemiologic information regarding sports injuries can be used to guide policy development for municipal planning and sport program development. The trends and demographic patterns described highlight general and sport-specific injury patterns in Ontario. Populations with the highest incidence of injury, most notably adolescents and men older than 50, may represent an appropriate population for injury risk prevention.

Cauda equina syndrome-a practical guide to definition and classification.

PURPOSE: International uniformity of definition and classification are crucial for diagnosis and management of cauda equina syndrome (CES). They are also useful for clinicians when discussing CES with patients and relatives, and for medicolegal purposes. METHODS: We reviewed published literature using PubMed on definition and classification of cauda equina syndrome since 2000 (21 years). Using the search terms 'cauda equina' and 'definition' or 'classification', we found and reviewed 212 papers. RESULTS: There were 17 different definitions of CES used in the literature. There were three well-defined methods of classification of CES. The two-stage system of incomplete CES (CESI) versus CES with retention (CESR) is the most commonly used classification, and has prognostic value although the details of this continue to be debated. CONCLUSION: We used the existing literature to propose a clear definition of CES. We also drew on peer-reviewed published literature that has helped to amplify and expand the CESI/CESR dichotomy, adding categories that are both less severe than CESI, and more severe than CESR, and we propose clear definitions in a table form to assist current and future discussion and management of CES.

Infrapatellar branch of the saphenous nerve: A review.

Iatrogenic injury to the infrapatellar branch of the saphenous nerve (IPBSN) is an uncommon but important complication of both open and arthroscopic procedures causing neuropathic pain symptoms in the anteromedial aspect of the knee. Whilst the use of ultrasound in the assessment of peripheral neuropathies is well-established, sonographic knowledge in the routine assessment of the IPBSN remains poor. We describe the sonographic assessment of the IPBSN by means of a review article, promulgating radiology's role in providing anatomical information pertaining to the IPBSN and its relationship to adjacent anatomical structures, surgical fixations or fibrous scar tissue.

Limiting the Risk of Osteoarthritis After Anterior Cruciate Ligament Injury: Are Health Care Providers Missing the Opportunity to Intervene?

OBJECTIVE: To understand what sports orthopedic surgeons (OS), primary care physicians (PCPs) with sports medicine training, and physical therapists (PTs) managing nonelite athletes with anterior cruciate ligament (ACL) injury tell their patients about their osteoarthritis (OA) risk. METHODS: An electronic survey was distributed by the Canadian Academy of Sport and Exercise Medicine (PCPs, OS), the Sports and Orthopedic Divisions of the Canadian Physiotherapy Association (PTs), and to OS identified through the Royal College of Physicians and Surgeons and the Canadian Orthopaedic Association. The survey included 4 sections: demographics, factors discussed, timing of discussions, and discussion of risk factors and their management. Proportions or means with 95% confidence intervals were calculated. RESULTS: A total of 501 health care professionals (HCPs) responded (98 PCPs, 263 PTs, and 140 OS). Of those responding, 70-77% of physicians reported always discussing OA risk, but only 35% of PTs did. All HCPs reported that patient activities perceived as detrimental to knee health, ACL reinjury, and simultaneous injury to other structures in the knee were most often the reason for discussing OA risk. OA risk was discussed at initial management post-injury (65-94%), with few discussing risk subsequently. Eighty percent of physicians and 99% of PTs indicated that PTs were suited to provide OA risk and management information. CONCLUSION: HCPs routinely managing people with ACL injury do not consistently discuss OA risk post-injury with them. Educational strategies for HCPs are urgently needed to develop care pathways inclusive of support for OA risk management following ACL injury.

Knee dislocation and associated injuries: an analysis of the American College of Surgeons National Trauma Data Bank.

PURPOSE: Knee dislocations (KDs) are potentially devastating injuries, leading to loss of function or limb in often young patients. This retrospective database review aims to determine the relative incidence and risk factors for KDs presenting to North American Level I and II trauma centers. METHODS: The National Trauma Data Bank (NTDB) was retrospectively interrogated using ICD-9-CM codes to identify KDs between 2010 and 2014 to derive KD incidence. KDs were stratified by age, sex, Injury Severity Score (ISS), Glasgow Coma Scale (GCS), drug and alcohol use, injury mechanism, open vs. closed KD, vascular injury and fracture. Each co-variate was tested against different mechanisms of injury, using Chi-squared tests and risk adjusted analyses to derive risk factors for KD. The same calculations were done for secondary outcomes (vascular and neurological injuries, compartment syndrome, amputation, and mortality). RESULTS: A total of 6454 KDs met the inclusion criteria (18/10,000 admissions). KDs occurred most commonly amongst men, aged 20-39, with an ISS score 1-14 and following motor vehicle collision (MVC). A vascular investigation was performed in 29%, with injury documented in 15% of KDs and 10.8% receiving a vascular procedure. Associated fractures were observed in 41.4% of KDs. Open injuries in 13.6%. Neurological injury documented in 6.2%, compartment syndrome in 2.7%, amputation in 3.8% (> 50% had vascular injury) and 2.8% died. MVC was the most common mechanism of injury (p < 0.001), significantly more common in young, male patients, associated with higher ISS and lower GCS, especially when drugs or alcohol were involved (p < 0.0001). Being male, having a vascular injury or open KD were all risk factors for compartment syndrome, amputation and neurological injuries. CONCLUSIONS: KDs are rare injuries, but their relative incidence may be increasing. Young, male patients involved in MVCs are risk factors for KDs and their associated injuries, such as neurological injuries, amputations and compartment syndrome. Vascular injury occurs at a frequency of around 15%. The findings of the current study may guide future research and help to inform clinicians on the expected rates of associated injuries in patients identified to have KD in a trauma center population. It informs regarding risk factors for KD, which may improve diagnosis rates of spontaneously reduced knee dislocations by increasing index of suspicion in high-risk patients and identifies specific links with impaired driving. LEVEL OF EVIDENCE: IV.

Risk of Ankle Fusion or Arthroplasty After Operatively and Nonoperatively Treated Ankle Fractures: A Matched Cohort Population Study.

OBJECTIVES: To define the risk and incidence of post-traumatic ankle arthritis requiring ankle arthroplasty or fusion after ankle fracture in a large cohort and compare that rate to matched healthy patients from the general population. DESIGN: Multiple databases were used to identify patients either treated surgically or nonsurgically for ankle fractures. Each patient was matched to 4 individuals from the general population (13.5 million) with no previous treatment for ankle fracture. Ankle fusion and replacement incidence was compared using the Kaplan-Meier analysis. MAIN OUTCOME MEASUREMENT: Incidence of arthroplasty or fusion in all patients managed for rotational ankle fractures. RESULTS: We identified 44,133 and 88,266 patients who had undergone operative management of ankle fracture (OAF) or nonoperative management of ankle fracture (NOAF) by an orthopaedic surgeon, respectively. Three hundred six (0.65%) patients who had OAF eventually underwent fusion or arthroplasty after a median 2.8 and 6.9 years, respectively. Among NOAF, n = 236 (0.17%) patients underwent fusion or arthroplasty after a median of 3.2 and 5.6 years, respectively. Surgical treatment, older age, comorbidity, and postinjury infection significantly increased the risk of fusion/arthroplasty. Compared with matched controls, the risk of fusion/arthroplasty was not independent of time, following an exponential decay pattern. OAF patient risk of fusion/arthroplasty was >20 times the general population in the 3 years after injury and approached the risk of NOAF by 14 years. CONCLUSIONS: Compared with a matched control group, and after adjustment for medical comorbidity, rotational ankle fractures requiring surgical open reduction internal fixation increased the likelihood of arthroplasty or fusion by 3.5 times. This study allows for accurate prognostication of patient risk of arthroplasty or fusion, using patient- and injury-specific risk factors, both immediately after the initial injury and then subsequently during the follow up. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Safety, tolerability, clinical, and joint structural outcomes of a single intra-articular injection of allogeneic mesenchymal precursor cells in patients following anterior cruciate ligament reconstruction: a controlled double-blind randomised trial.

BACKGROUND: Few clinical trials have investigated the safety and efficacy of mesenchymal stem cells for the management of post-traumatic osteoarthritis. The objectives of this pilot study were to determine the safety and tolerability and to explore the efficacy of a single intra-articular injection of allogeneic human mesenchymal precursor cells (MPCs) to improve clinical symptoms and retard joint structural deterioration over 24 months in patients following anterior cruciate ligament (ACL) reconstruction. METHODS: In this phase Ib/IIa, double-blind, active comparator clinical study, 17 patients aged 18-40 years with unilateral ACL reconstruction were randomized (2:1) to receive either a single intra-articular injection of 75 million allogeneic MPCs suspended in hyaluronan (HA) (MPC + HA group) (n = 11) or HA alone (n = 6). Patients were monitored for adverse events. Immunogenicity was evaluated by anti-HLA panel reactive antibodies (PRA) against class I and II HLAs determined by flow cytometry. Pain, function, and quality of life were assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and SF-36v2 scores. Joint space width was measured from radiographs, and tibial cartilage volume and bone area assessed from magnetic resonance imaging (MRI). RESULTS: Moderate arthralgia and swelling within 24 h following injection that subsided were observed in 4 out of 11 in the MPC + HA group and 0 out of 6 HA controls. No cell-related serious adverse effects were observed. Increases in class I PRA >10% were observed at week 4 in the MPC + HA group that decreased to baseline levels by week 104. Compared with the HA group, MPC + HA-treated patients showed greater improvements in KOOS pain, symptom, activities of daily living, and SF-36 bodily pain scores (p < 0.05). The MPC + HA group had reduced medial and lateral tibiofemoral joint space narrowing (p < 0.05), less tibial bone expansion (0.5% vs 4.0% over 26 weeks, p = 0.02), and a trend towards reduced tibial cartilage volume loss (0.7% vs -4.0% over 26 weeks, p = 0.10) than the HA controls. CONCLUSIONS: Intra-articular administration of a single allogeneic MPC injection following ACL reconstruction was safe, well tolerated, and may improve symptoms and structural outcomes. These findings suggest that MPCs warrant further investigations as they may modulate some of the pathological processes responsible for the development of post-traumatic osteoarthritis following ACL reconstruction. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT01088191 ) registration date: March 11, 2010.

Rectus Abdominis Rhabdomyolysis: Report of 2 Cases.

Exercise-induced rhabdomyolysis is an unusual clinical entity for physicians and one that is frequently misdiagnosed. With the ever-increasing use of sonography by radiologists, sonographers, and sports physicians in the diagnosis of acute muscle injury, recognition of the typical sonographic appearance of rhabdomyolysis is paramount. Current literature using high-resolution ultrasound equipment is limited, with much of the literature offering dated or incongruent descriptions. We describe the sonographic findings of hyperechoic muscle and a hypoechoic halo of edema in 2 proven cases of rectus abdominis rhabdomyolysis after exercise.

Ultrasound Screening for Adverse Local Tissue Reaction after Hip Arthroplasty.

Early detection of adverse local tissue reaction (ALTR) to prosthetic hip wear debris is vital to improve the success of revision surgery. Magnetic resonance imaging with metal artefact reduction sequencing (MARS MRI) is considered the modality of choice to provide cross-sectional imaging of the soft tissues. The areas adjacent to the prosthesis are, however, not readily imaged using these protocols. Ultrasound has also been recommended as an imaging modality in the follow-up of hip replacement surgery. We decided to characterise the typical ultrasound findings in a group of patients undergoing routine biennial review of arthroplastic hips with particular reference to the hip capsule, femoral neck and iliopsoas bursa and tendon adjacent to the implant. Fifty-two patients with a mean (±SD) age of 60.4 (±12) y were prospectively recruited. Twelve patients had bilateral hip prostheses, giving 64 hips for analysis. Mean (±SD) age of the prosthesis in situ was 8.2 (±3.3) y. Data were grouped on the basis of the shape of the iliofemoral ligament. The median (range) maximal anteroposterior synovial thickness was 5 (2-8) mm in the normal concave iliofemoral ligament group and 7 (4-56) mm in the abnormal straight/convex iliofemoral ligament group (p = 0.001). The anteroposterior iliopsoas tendon measurement was 5 (3-8) mm in the normal group and 5 (4-8) mm in the abnormal group (p = 0.065). ALTR development in asymptomatic well-functioning prostheses may be recognised earlier using ultrasound rather than MARS MRI by carefully assessing the shape of the iliofemoral ligament. Ultrasound findings of an abnormal straight or convex ligament may be suggestive of early ALTR and warrant streaming of patients to a more frequent surveillance program.

A Systematic Review and Appraisal of Clinical Practice Guidelines for Musculoskeletal Soft Tissue Injuries and Conditions.

BACKGROUND: Clinical practice guidelines (CPGs) are published by several sports medicine institutions. A systematic evaluation can help identify the highest quality CPGs for clinical use and identify any deficiencies that remain. PURPOSE: To identify and appraise CPGs relevant to clinical sports medicine professionals. STUDY DESIGN: Systematic review. METHODS: Predetermined selection criteria were utilized by 2 reviewers who independently identified published CPGs before January 1, 2014. CPGs were excluded if they focused on injured workers, radiological criteria, medical pathology, or the axial skeleton (back/neck). The remaining guidelines were scored by 6 reviewers with different clinical backgrounds using the Appraisal of Guidelines for Research and Evaluation II (AGREE II). Scores lower than 50% indicated deficiency. Scores were also stratified by the publishing institution and anatomic location and compared using Kruskal-Wallis tests. The Spearman correlation coefficient was used to assess the range of interobserver agreement between the evaluators. RESULTS: Seventeen CPGs met the inclusion criteria. The majority of guidelines pertained to the knee, ankle, or shoulder. Interobserver agreement was strong ( r = 0.548-0.740), and mean total scores between nonsurgical (107.8) and surgical evaluators (109.3) were not statistically different. Overall guideline quality was variable but not deficient for 16 of 17 guidelines (>50%), except regarding clinical "applicability" and "editorial independence." No difference was found between CPGs of the knee, shoulder, foot/ankle, or chronic conditions. However, CPG publishing institutions had significantly different scores; the American Academy of Orthopaedic Surgeons (AAOS) guidelines scored significantly higher (141.4) than the total mean score (108.0). CONCLUSION: The overall quality of sports medicine CPGs was variable but generally not deficient, except regarding applicability and editorial independence. Bias through poor editorial independence is a concern. To improve future guideline quality, authors should pay particular attention to these areas and use existing highest quality guidelines, or the AGREE II instrument, as templates. CPGs dedicated to anatomic areas other than the knee, ankle, and shoulder are needed.

A Prospective Randomized Clinical Trial in Total Hip Arthroplasty-Comparing Early Results Between the Direct Anterior Approach and the Posterior Approach.

BACKGROUND: We report a prospective randomized study comparing early clinical results between the direct anterior approach (DAA) and posterior approach (PA) in primary hip arthroplasty. METHODS: Surgeries were performed by 2 senior hip arthroplasty surgeons. Seventy-two patients with complete data were assessed preoperatively 2, 6, and 12 weeks postoperatively. The primary outcomes were the Western Ontario McMasters Arthritis Index and Oxford Hip Scores. Secondary outcome measures included the EuroQoL, 10-meter walk test, and clinical and radiographic parameters. RESULTS: Data analyses showed no difference between DAA (n = 35) and PA (n = 37) groups when comparing total scores for primary outcomes. No significant differences were observed for 10-meter walk test, EuroQoL, and radiographic analyses. Subgroup analysis for surgeon 1 identified that the DAA group had shorter acute hospital stay, less postoperative opiate requirements, and smaller wounds. However, this was offset by increased operative time, higher intraoperative blood loss, and weaker hip flexion at 2 and 6 weeks. Subgroup analysis of items on the Western Ontario McMasters Arthritis Index and Oxford Hip Score identified that hip flexion activity favored the DAA group up to 6 weeks postoperatively. There was an 83% incidence of lateral cutaneous nerve of thigh neuropraxia at the 12-week mark in the DAA group. No neuropraxias occurred in the PA group. One dislocation occurred in each group. A single patient from the DAA group required reoperation for leg-length discrepancy. CONCLUSION: DAA total hip arthroplasty (THA) has comparable results with PA THA. Choice of surgical approach for THA should be based on patient factors, surgeon preference, and experience.

Ultrasound-Guided Radiofrequency Denervation of the Medial Calcaneal Nerve.

OBJECTIVE: Plantar fasciosis is a common complaint of athletes, particularly for runners. The medial calcaneal nerve (MCN) may play a role in the pain syndrome, and radiofrequency (RF) denervation has been previously reported. The hypothesis is that ultrasound-guided denervation of the MCN results in symptomatic improvement. DESIGN: Retrospective cohort. SETTING: Private practice. PATIENTS: Twenty-nine patients previously receiving ultrasound-guided RF denervation of the MCN, having failed conservative therapy, were assessed in 2 groups, those more than (group 1, n = 16) or less than (group 2, n = 13) 6 months since the procedure. INTERVENTIONS: Ultrasound-guided RF denervation of the MCN. MAIN OUTCOME MEASURES: Pain scores before denervation, as well as at maximal pain relief and the time of the interview. Levels of satisfaction and attitudes toward surgery were also assessed. RESULTS: Pain scores decreased significantly in both groups, for both best and residual pain scores. Group 1 mean pain scores were 8.56 before procedure, 2.81 (P < 0.001 compared to baseline) at best pain score, and 3.75 (P < 0.01) residual pain score. Group 2 mean pain scores were 7.23 before procedure, 3.77 (P < 0.01) at best pain score and 4.92 (P < 0.01) residual pain score. Levels of satisfaction were predominantly positive (69% of group 1% and 54% of group 2 were either somewhat or very satisfied), with attitudes toward surgery unchanged. CONCLUSIONS: For patients with refractory plantar heel pain, ultrasound-guided denervation of the MCN can potentially improve symptoms, although efficacy needs assessing in comparative studies. CLINICAL RELEVANCE: Ultrasound-guided denervation of the MCN provides a further management option for patients with refractory plantar fasciosis.

Microfracture for chondral defects: assessment of the variability of surgical technique in cadavers.

PURPOSE: The purpose of this study was to assess the variability of the microfracture technique when performed by experienced knee arthroscopy surgeons. METHOD: Four surgeons were each asked to perform microfracture on six preformed cartilage defects in fresh human cadaveric knees. Surgeons were instructed on penetration depth, inter-hole distance, and to place the holes perpendicular to the subchondral surface. Micro-computed tomography was used to calculate depth error, inter-hole distance error, and deviation of penetration angles from the perpendicular. RESULTS: All surgeons misjudged depth and inter-hole distance, tending to make microfracture holes too deep (depth error 1.1 mm ± 1.9) and too close together (inter-hole distance error: -0.8 mm ± 0.4). Fifty-one per cent of holes were angled more than 10° from the perpendicular (range 2.6°-19.8°). Both depth and distance errors were significantly lower in the trochlear groove than on the femoral condyle (p < 0.05). Surface shearing was associated with both penetration depth >4 mm and angles >20°. Inter-hole infraction occurred in holes closer than 2.5 mm to each other. CONCLUSION: Even experienced knee arthroscopy surgeons demonstrate inconsistency in surgical technique when performing microfracture. While further research will be required to demonstrate that these variations in surgical technique are associated with poorer clinical outcomes after microfracture, surgeons should attempt to minimizing such variations in order to prevent surface shearing and inter-hole infraction.

Creation of a histone deacetylase 6 inhibitor and its biological effects [corrected].

We report the development of a potent, selective histone deacetylase 6 (HDAC6) inhibitor. This HDAC6 inhibitor blocks growth of normal and transformed cells but does not induce death of normal cells. The HDAC6 inhibitor alone is as effective as paclitaxel in anticancer activity in tumor-bearing mice.

CCR 20th Anniversary Commentary: Vorinostat-Gateway to Epigenetic Therapy.

The study by Kelly and colleagues, published in the September 1, 2003, issue of Clinical Cancer Research, established the safety and biologic activity of the first-in-class histone deacetylase inhibitor, vorinostat, which was administered intravenously. Subsequent studies led to the development of oral vorinostat and the regulatory approval of vorinostat for cutaneous T-cell lymphomas, which opened the door for the next generation of inhibitors.

Perceived personal importance of exercise and fears of re-injury: a longitudinal study of psychological factors related to activity after anterior cruciate ligament reconstruction.

BACKGROUND: Psychological perceptions are increasingly being recognized as important to recovery and rehabilitation post-surgery. This research longitudinally examined perceptions of the personal importance of exercise and fears of re-injury over a three-year period post anterior cruciate ligament (ACL) reconstruction. Stability and change in psychological perceptions was examined, as well as the association of perceptions with time spent in different types of physical activity, including walking, household activities, and lower and higher risk for knee injury activities. METHODS: Participants were athletes, 18-40 years old, who underwent ACL reconstruction for first-time ACL injuries. They were recruited from a tertiary care centre in Toronto, Canada. Participants completed interviewer-administered questionnaires pre-surgery and at years one, two and three, postoperatively. Questions assessed demographics, pain, functional limitations, perceived personal importance of exercise, fear of re-injury and physical activities (i.e., walking; household activities; lower risk for knee injury activities; higher risk for knee injury activities). Analyses included fixed-effect longitudinal modeling to examine the association of a fear of re-injury and perceived personal importance of exercise and changes in these perceptions with the total hours spent in the different categories of physical activities, controlling for other factors. RESULTS: Baseline participants were 77 men and 44 women (mean age = 27.6 years; SD = 6.2). At year three, 78.5% of participants remained in the study with complete data. Fears of re-injury decreased over time while personal importance of exercise remained relatively stable. Time spent in walking and household activities did not significantly change with ACL injury or surgery. Time spent in lower and higher risk of knee injury physical activity did not return to pre-injury levels at three years, post-surgery. Greater time spent in higher risk of knee injury activities was predicted by decreases in fears of re-injury and by greater personal importance of exercise. CONCLUSIONS: This study highlights not only fears of re-injury, which has been documented in previous studies, but also the perceived personal importance of exercise in predicting activity levels following ACL reconstructive surgery. The findings can help in developing interventions to aid individuals make decisions about physical activities post knee injury and surgery.

The epidemiology of revision anterior cruciate ligament reconstruction in Ontario, Canada.

BACKGROUND: Knowledge of the rate of and risk factors for re-revision, reoperation, and readmission after revision anterior cruciate ligament reconstruction (ACLR) is limited. PURPOSE: To determine the rate of and risk factors for re-revision, reoperation, and readmission after revision ACLR. STUDY DESIGN: Descriptive epidemiology study. METHODS: All patients who underwent first revision ACLR in Ontario, Canada, from January 2004 to December 2010 were identified and followed until December 2012. Exclusions included age <16 years, previous osteotomy, or multiligament knee reconstruction. The main outcome was re-revision ACLR. Secondary outcomes included reoperation (irrigation and debridement [I&D], meniscectomy, manipulation under anesthesia, contralateral ACLR, and total knee arthroplasty) and readmission. Survival to re-revision was determined using the Kaplan-Meier approach. A Cox proportional hazards model or logistic regression were used to determine the influence of patient, surgical, and provider factors on outcomes. A post hoc analysis was performed to determine the influence of the aforementioned factors on postoperative infection risk. RESULTS: Overall, 827 patients were included (median age, 30 years; 58.8% males). Single-stage revisions comprised 92.9% of cases, and a meniscal procedure (repair or debridement) was performed in 45.3% of cases. The re-revision rate at a mean follow-up of 4.8 ± 2.2 years was 4.4%, and the 5-year survival rate was 95.4%. The rates of I&D, meniscectomy, contralateral ACLR, and readmission were 0.8%, 3.1%, 3.4%, and 4.1%, respectively. Manipulation under anesthesia and total knee arthroplasty were rare. Young age significantly increased contralateral ACLR risk (risk decreased by 5.1% with each year of age >16 years; P = .02) but not re-revision ACLR risk. Low surgeon's annual volume of revision ACLR (<4 revisions/year: odds ratio, 1.2; P = .02) and male sex (odds ratio, 13.3; P = .01) significantly increased overall infection risk; male sex also influenced I&D risk. CONCLUSION: Re-revision, reoperation, and readmission rates after revision ACLR were low, and the risk for I&D, infection, and contralateral ACLR were influenced by male sex, low surgeon volume, and young age, respectively. CLINICAL RELEVANCE: This is the first study to determine morbidity rates and risk factors after revision ACLR, providing reference data from the general population.