MRI use leading up to total knee arthroplasty: a retrospective cohort study.

BACKGROUND: Demand for total knee arthroplasty (TKA) is increasing as it remains the gold-standard treatment for end-stage osteoarthritis (OA) of the knee. Magnetic resonance imaging (MRI) scans of the knee are not indicated for diagnosing knee OA and represent a possible delay to orthopaedic surgeon referral and unnecessary expenditure. The purpose of this study was to determine the proportion of patients who underwent an MRI in the two years prior to their primary TKA for OA and determine patient and physician associations with increased MRI usage. METHODS: This is a population-based cohort study using administrative data from Ontario, Canada. All patients over 40 years old who underwent their first primary TKA between April 1, 2008, and March 31, 2019, were included. Statistical analyses were performed using SAS and included the Cochran-Armitage test for trend of MRI prior to surgery. A predictive multivariable regression model was used to determine features correlated to receiving an MRI. RESULTS: There were 194,989 eligible first-time TKA recipients, of which 38,244 (19.6%) received an MRI in the two years prior to their surgery. The majority of these (69.6%) were ordered by primary care physicians. Patients who received an MRI were younger, had fewer comorbidities and were more affluent than patients who did not (p < 0.001). MRI use prior to TKA increased from 2008 to 2018 (p < 0.001). CONCLUSION: Despite MRIs rarely being indicated for the work-up of end-stage OA, nearly one in five patients have an MRI in the two years prior to their TKA. This may be increasing healthcare expenditure and surgical wait-times.

Biomechanical Comparison of 3 Medial Patellofemoral Complex Reconstruction Techniques Shows Medial Overconstraint but No Significant Difference in Patella Lateralization and Contact Pressure.

PURPOSE: The purpose of this study was to investigate biomechanical differences of medial patellofemoral ligament (MPFL) reconstruction, medial quadriceps tendon femoral ligament (MQTFL) reconstruction, and a combination of these techniques to restore lateral patellar constraint and contact pressures. METHODS: Eight fresh frozen cadaver knees were mounted to a custom jig with physiological quadriceps tendon loading. Flexion angles and contact pressure (CP) were dynamically measured using Tekscan® pressure sensors and Polhemus® Liberty 6 degree of freedom (6DOF) positioning sensors in the following conditions: 1) intact 2) MPFL and MQTFL deficient, 3) MPFL reconstructed, 4) Combined MPFL + MQTFL reconstructed, and 5) MQTFL reconstructed. Lateral patellar translation was tested using horizontally directed 30 N force applied at 30° of knee flexion. The knees were flexed in dynamic fashion, and CP values were recorded for 10°, 20°, 30°, 50°, 70°, and 90° degrees of flexion. Group differences were assessed with ANOVA's followed by pairwise comparisons with Bonferroni correction. RESULTS: MPFL (P = .002) and combined MPFL/MQTFL (P = .034) reconstruction significantly reduced patellar lateralization from +19.28% (9.78%, 28.78%) in the deficient condition to -17.57% (-27.84%, -7.29%) and -15.56% (-33.61%, 2.30%), respectively. MPFL reconstruction was most restrictive and MQTFL reconstruction the least -7.29% (-22.01%, 7.45%). No significant differences were found between the three reconstruction techniques. Differences in CP between the three reconstruction techniques were not significant (<.02 MPa) at all flexion angles. CONCLUSION: The present study found no significant difference for patellar lateralization and patellofemoral CP between MPFL, combined MPFL/MQTFL, and MQTFL reconstruction. All 3 techniques resulted in stronger lateral patellar constraint compared to the native state, while the MQTFL reconstruction emulated the intact state the closest. CLINICAL RELEVANCE: Various surgical techniques for medial patellofemoral complex reconstruction can restore patellar stability with similar patellofemoral articular pressures.

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.

Effects of hospital funding reform on wait times for hip fracture surgery: a population-based interrupted time-series analysis.

BACKGROUND: Health care funding reforms are being used worldwide to improve system performance but may invoke unintended consequences. We assessed the effects of introducing a targeted hospital funding model, based on fixed price and volume, for hip fractures. We hypothesized the policy change was associated with reduction in wait times for hip fracture surgery, increase in wait times for non-hip fracture surgery, and increase in the incidence of after-hours hip fracture surgery. METHODS: This was a population-based, interrupted time series analysis of 49,097 surgeries for hip fractures, 10,474 for ankle fractures, 1,594 for tibial plateau fractures, and 40,898 for appendectomy at all hospitals in Ontario, Canada between April 2012 and March 2017. We used segmented regression analysis of interrupted monthly time series data to evaluate the impact of funding reform enacted April 1, 2014 on wait time for hip fracture repair (from hospital presentation to surgery) and after-hours provision of surgery (occurring between 1700 and 0700 h). To assess potential adverse consequences of the reform, we also evaluated two control procedures, ankle and tibial plateau fracture surgery. Appendectomy served as a non-orthopedic tracer for assessment of secular trends. RESULTS: The difference (95 % confidence interval) between the actual mean wait time and the predicted rate had the policy change not occurred was - 0.46 h (-3.94 h, 3.03 h) for hip fractures, 1.46 h (-3.58 h, 6.50 h) for ankle fractures, -3.22 h (-39.39 h, 32.95 h) for tibial plateau fractures, and 0.33 h (-0.57 h, 1.24 h) for appendectomy (Figure 1; Table 3). The difference (95 % confidence interval) between the actual and predicted percentage of surgeries performed after-hours - 0.90 % (-3.91 %, 2.11 %) for hip fractures, -3.54 % (-11.25 %, 4.16 %) for ankle fractures, 7.09 % (-7.97 %, 22.14 %) for tibial plateau fractures, and 1.07 % (-2.45 %, 4.59 %) for appendectomy. CONCLUSIONS: We found no significant effects of a targeted hospital funding model based on fixed price and volume on wait times or the provision of after-hours surgery. Other approaches for improving hip fracture wait times may be worth pursuing instead of funding reform.

Risk of Total Hip Arthroplasty After Acetabular Fracture Fixation: The Importance of Age.

BACKGROUND: Geriatric patients are the most rapidly growing cohort of patients sustaining acetabular fractures (AFs). The purpose of this study was to examine the risk of a secondary total hip arthroplasty (THA) in older patients (>60 year old) with a prior AF open reduction internal fixation (ORIF) compared with younger patients (<60 year old) with an AF ORIF on a large population level. METHODS: Using administrative health care data from 1996 to 2010 inclusive of all 202 hospitals in Ontario, Canada, all adult patients with an AF ORIF and a minimum of two year follow-up were identified and included. The risk of THA was examined using a Cox proportional hazards model adjusting for patient risk factors. Secondary outcomes included surgical complications and all-cause mortality. RESULTS: A total of 1725 patients had an AF ORIF; 1452 (84.2%, mean age of 38.3 ± 12.1 years) aged <60 years ("younger") and 273 (15.8%, mean age of 69.9 ± 7.8 years) > 60 years ("older"). The mean (SD) follow-up time for all patients was 6.9 (4.2) years. In older patients, 19.4% (53 of 273) went on to receive a secondary THA with a median time to event of 3.9 years, compared with 12.9% (187 of 1452) in the younger patient cohort with a median time of 6.9 years (HR 1.7, 95% CI: 1.2-2.3). As expected, older patients had a higher 90-day mortality rate compared with younger patients (7.7% vs. 0.7%, respectively; HR 9.2, 95% CI: 4.3-19.9; P < .001). CONCLUSION: Older patients with an AF ORIF are at a significantly higher risk for a secondary THA than younger patients with an AF ORIF.

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.

Association between socioeconomic deprivation and surgical complications in adults undergoing ankle fracture fixation: a population-based analysis

Background: Few studies have investigated the outcomes of surgical fracture care among socially deprived patients despite the increased incidence of fractures and the inequality of care received in this group. We evaluated whether socioeconomic deprivation affected the complications and subsequent management of marginalized/homeless patients following surgery for ankle fracture. Methods: In this retrospective, population-based cohort study involving 202 hospitals in Ontario, Canada, we evaluated 45 444 patients who underwent open reduction and internal fixation (ORIF) for ankle fracture performed by 710 different surgeons between Jan. 1, 1994, and Dec. 31, 2011. Multivariable logistic regression models were used to assess the association between deprivation and shorter-term outcomes within 1 year (implant removal, repeat ORIF, irrigation and débridement owing to infection, and amputation). Multivariable Cox proportional hazards models were used to assess longer-term outcomes up to 20 years (ankle fusion and ankle arthroplasty). Results: A higher level of deprivation was associated with an increased risk of irrigation and débridement (quintile 5 v. quintile 1: odds ratio [OR] 2.14, 95% confidence interval [CI] 1.25­3.67, p = 0.0054) and amputation (quintile 4 v. quintile 1: OR 3.56, 95% CI 1.01­12.4, p = 0.0466). It was more common for less deprived patients to have their hardware removed (quintile 5 v. quintile 1: OR 0.822, 95% CI 0.76­0.888, p < 0.0001). There was no correlation between marginalization and subsequent revision ORIF, ankle fusion, or ankle arthroplasty. Conclusion: Marginalized patients are at a significantly increased risk of infection and amputation following surgical treatment of ankle fractures. However, these complications are still extremely uncommon among this group. Socioeconomic deprivation should not prohibit marginalized patients from receiving surgery for unstable ankle fractures.

Contexte: Malgré l'incidence accrue des fractures et les inégalités dans la prestation des soins chez les patients au statut socio-économique précaire, peu d'études se sont penchées sur les résultats de la chirurgie pour fracture chez cette population. Nous avons voulu vérifier si une situation socio-économique précaire influait sur les complications et la prise en charge subséquente des patients marginalisés/itinérants après une chirurgie pour fracture de la cheville. Méthodes: Au cours de cette étude de cohorte rétrospective basée dans la population regroupant 202 hôpitaux en Ontario, au Canada, nous avons évalué 45 444 patients ayant subi une réduction ouverte avec fixation interne (ROFI) pour fracture de la cheville, effectuée par 710 chirurgiens différents entre le 1er janvier 1994 et le 31 décembre 2011. Des modèles de régression logistique multivariée ont servi à évaluer le lien entre le statut précaire et les résultats à court terme (au cours de l'année) (retrait de l'implant, réintervention pour ROFI, irrigation et débridement en raison d'une infection, et amputation). Des modèles d'analyse multivariée à risques proportionnels de Cox ont servi à évaluer les résultats à plus long terme, jusqu'à 20 ans (fusion de la cheville et arthroplastie de la cheville). Résultats: Le risque d'irrigation et débridement (quintile 5 c. quintile 1 : rapport des cotes [RC] 2,14, intervalle de confiance [IC] de 95 % 1,25­3,67, p = 0,0054) et d'amputation (quintile 4 c. quintile 1 : RC 3,56, IC de 95 % 1,01­12,4, p = 0,0466) était proportionnel à la précarité de la situation des individus. Les patients moins défavorisés étaient moins susceptibles de se faire retirer leurs implants (quintile 5 c. quintile 1 : RC 0,822, IC de 95 % 0,76­0,888, p < 0,0001). On n'a observé aucune corrélation entre la marginalisation et une réintervention pour ROFI, fusion de la cheville ou arthroplastie de la cheville. Conclusion: Les patients marginalisés sont exposés à un risque significativement plus élevé d'infection et d'amputation après un traitement chirurgical pour fracture de la cheville. Cependant, de telles complications demeurent extrêmement rares chez cette population. Un statut socioéconomique précaire ne devrait pas empêcher les patients marginalisés de recevoir une chirurgie lors de fractures instables de la cheville.

Reporting and evaluating wait times for urgent hip fracture surgery in Ontario, Canada.

BACKGROUND: Although a delay of 24 hours for hip fracture repair is associated with medical complications and costs, it is unknown how long patients wait for surgery for hip fracture. We describe novel methods for measuring exact urgent and emergent surgical wait times (in hours) and the factors that influence them. METHODS: Adults aged 45 years and older who underwent surgery for hip fracture (the most common urgently performed procedure) in Ontario, Canada, between 2009 and 2014 were eligible. Validated data from linked health administrative databases were used. The primary outcome was the time elapsed from hospital arrival recorded in the National Ambulatory Care Reporting System until the time of surgery recorded in the Discharge Abstract Database (in hours). The influence of patient, physician and hospital factors on wait times was investigated using 3-level, hierarchical linear regression models. RESULTS: Among 42 230 patients with hip fracture, the mean (SD) wait time for surgery was 38.76 (28.84) hours, and 14 174 (33.5%) patients underwent surgery within 24 hours. Variables strongly associated with delay included time for hospital transfer (adjusted increase of 26.23 h, 95% CI 25.38 to 27.01) and time for preoperative echocardiography (adjusted increase of 18.56 h, 95% CI 17.73 to 19.38). More than half of the hospitals (37 of 72, 51.4%), compared with 4.8% of surgeons and 0.2% of anesthesiologists, showed significant differences in the risk-adjusted likelihood of delayed surgery. INTERPRETATION: Exact wait times for urgent and emergent surgery can be measured using Canada's administrative data. Only one-third of patients received surgery within the safe time frame (24 h). Wait times varied according to hospital and physician factors; however, hospital factors had a larger impact.

Does Platelet-Rich Plasma Lead to Earlier Return to Sport When Compared With Conservative Treatment in Acute Muscle Injuries? A Systematic Review and Meta-analysis.

PURPOSE: To compare the time to return to sport and reinjury rate after platelet-rich plasma (PRP) injection versus control therapy (i.e., physiotherapy or placebo injection) in patients with acute grade I or II muscle strains. METHODS: All eligible studies comparing PRP against a control in the treatment of acute (≤7 days) grade I or II muscle strains were identified. The primary outcome was time to return to play. The secondary outcome was the rate of reinjury at a minimum of 6 months of follow-up. Subgroup analysis was performed to examine the efficacy of PRP in hamstring muscle strains alone. The checklist to evaluate a report of a nonpharmacologic trial (CLEAR-NPT) was used to assess the quality of studies. RESULTS: Five randomized controlled trials including a total of 268 patients with grade I and II acute muscle injuries were eligible for review. The pooled results revealed a significantly earlier return to sport for the PRP group when compared with the control group (mean difference, -5.57 days [95% confidence interval, -9.57 to -1.58]; P = .006). Subgroup analysis showed no difference in time to return to sport when comparing PRP and control therapy in grade I and II hamstring muscle strains alone (P = .19). No significant difference was noted in the rate of reinjury between the 2 groups (P = .50) at a minimum of 6 months of follow-up. CONCLUSIONS: Evidence from the current literature, although limited, suggests that the use of PRP may result in an earlier return to sport among patients with acute grade I or II muscle strains without significantly increasing the risk of reinjury at 6 months of follow-up. However, no difference in time to return to sport was revealed when specifically evaluating those with a grade I or II hamstring muscle strain. LEVEL OF EVIDENCE: Level II, meta-analysis of level I and II studies.

Dynamically tensioned ACL functional knee braces reduce ACL and meniscal strain.

PURPOSE: The effectiveness of ACL functional knee braces to reduce meniscal and ACL strain after ACL injury or reconstruction is not well understood. A new dynamic knee tensioning brace system has been designed to apply an active stabilizing force to the knee. The ability of this system to reduce tissue strains is unknown. The purpose of this study was to test the ability of the dynamically tensioned brace to reduce strain in both the ACL and meniscus during rehabilitation activities. METHODS: A combined in vivo/in silico/in vitro method was used to study three activities: gait, double leg squat, and single leg squat. Muscle forces and kinematics for each activity were derived through in vivo motion capture and applied to seven cadaveric knee specimens fitted with custom braces. Medial meniscal strain and ACL strain were measured in ACL intact, deficient and reconstructed conditions. RESULTS: The brace lowered peak and average meniscal strain in ACL deficient knees (P < 0.05) by an average of 1.7%. The brace was also found to lower meniscal strain in reconstructed knees (1.1%) and lower ACL strain in ACL intact (1.3%) and reconstructed knees (1.4%) (P < 0.05). CONCLUSIONS: This study supports the use of a brace equipped with a dynamic tensioning system to lower meniscal strain in ACL-deficient knees. Its use may help decrease the risk of subsequent meniscal tears in chronic ACL deficiency or delayed reconstruction. In ACL-intact and reconstructed knees, the brace may be beneficial in injury prophylaxis or in protecting the ACL graft following reconstruction. These results will aid clinicians make informed recommendations for functional brace use in patients with unstable knees. LEVEL OF EVIDENCE: II.

Clinical and radiographic outcomes of meniscus surgery and future targets for biologic intervention: A review of data from the MOON Group.

Meniscus injury and treatment occurred with the majority of anterior cruciate ligament reconstructions (ACLR) in the multicenter orthopedic outcomes (MOON) cohort. We describe the patient-reported outcomes, radiographic outcomes, and predictors of pain from meniscus injuries and treatment in the setting of ACLR. Patient-reported outcomes improve significantly following meniscus repair with ACLR, but differences exist based on the meniscus injury laterally (medial or lateral). Patients undergoing medial meniscus repair have worse patient-reported outcomes and more pain compared to those with uninjured menisci. However, lateral meniscal tears can be repaired with similar outcomes as uninjured menisci. Medial meniscal treatment (meniscectomy or repair) results in a significant loss of joint space at 2 years compared to uninjured menisci. Menisci treated with excision had a greater degree of joint space loss compared to those treated with repair. Clinically significant knee pain is more common following injuries to the medial meniscus and increased in patients who undergo early re-operation after initial ACLR. Future research efforts aimed at improving outcomes after combined ACLR and meniscus treatment should focus on optimizing biologic and mechanical environments that promote healing of medial meniscal tears sustained during ACL injury.

Direct medical costs of motorcycle crashes in Ontario.

BACKGROUND: There is no reliable estimate of costs incurred by motorcycle crashes. Our objective was to calculate the direct costs of all publicly funded medical care provided to individuals after motorcycle crashes compared with automobile crashes. METHODS: We conducted a population-based, matched cohort study of adults in Ontario who presented to hospital because of a motorcycle or automobile crash from 2007 through 2013. For each case, we identified 1 control absent a motor vehicle crash during the study period. Direct costs for each case and control were estimated in 2013 Canadian dollars from the payer perspective using methodology that links health care use to individuals over time. We calculated costs attributable to motorcycle and automobile crashes within 2 years using a difference-in-differences approach. RESULTS: We identified 26 831 patients injured in motorcycle crashes and 281 826 injured in automobile crashes. Mean costs attributable to motorcycle and automobile crashes were $5825 and $2995, respectively (p < 0.001). The rate of injury was triple for motorcycle crashes compared with automobile crashes (2194 injured annually/100 000 registered motorcycles v. 718 injured annually/100 000 registered automobiles; incidence rate ratio [IRR] 3.1, 95% confidence interval [CI] 2.8 to 3.3, p < 0.001). Severe injuries, defined as those with an Abbreviated Injury Scale ≥ 3, were 10 times greater (125 severe injuries annually/100 000 registered motorcycles v. 12 severe injuries annually/100 000 registered automobiles; IRR 10.4, 95% CI 8.3 to 13.1, p < 0.001). INTERPRETATION: Considering both the attributable cost and higher rate of injury, we found that each registered motorcycle in Ontario costs the public health care system 6 times the amount of each registered automobile. Medical costs may provide an additional incentive to improve motorcycle safety.

The effect of patient, provider and surgical factors on survivorship of high tibial osteotomy to total knee arthroplasty: a population-based study.

PURPOSE: The aim of this study was to identify the survivorship of high tibial osteotomy (HTO) to total knee arthroplasty (TKA) on a population level, and identify the patient, provider and surgical factors that influenced eventual TKA. METHODS: Administrative records from physician billings and hospital admissions were used to identify all adults in Ontario, Canada, who underwent an HTO from 1994 to 2010. The primary outcome was time to TKA, which was estimated using Kaplan-Meier (KM) survival analysis. A Cox proportional hazards model examined the risk associated with patient factors (age, sex, income and co-morbidity score), provider factors (hospital status, surgeon volume and surgeon year in practice) and surgical factors (concurrent ligament reconstruction or bone grafting; and previous chondral or meniscal surgery). RESULTS: A total of 2671 patients who underwent HTO met inclusion. The median age was 46 years (interquartile range 39-53 years), and 62 % were male. The KM survivorship of HTO to TKA at 10 years was 0.67 ± 0.01. Older age [HR 1.05 (95 % CI 1.04, 1.06), p < 0.001; 5 % increased risk for each year over age 46], female sex [HR 1.35 (95 % CI 1.17, 1.55), p < 0.001], higher comorbidity score [HR 1.58 (95 % CI 1.12, 2.22), p = 0.009] and a prior history of arthroscopy/meniscectomy [HR 1.24 (95 % CI 1.08, 1.43), p = 0.002] increased the risk of eventual TKA. However, HTO with concurrent ligament reconstruction was associated with lower [HR 0.62 (95 % CI 0.43, 0.88), p = 0.008] risk of eventual TKA. CONCLUSION: In this population, two-thirds of patients were able to avoid a TKA for 10 years after HTO. Specific factors such as older age, female sex, higher comorbidity and prior meniscectomy lowered survival rates. An understanding of patient risk factors for conversion to TKA may help guide surgeons in their selection of patients who will benefit most from HTO. LEVEL OF EVIDENCE: Retrospective cohort study, III.

Association Between Wait Time and 30-Day Mortality in Adults Undergoing Hip Fracture Surgery.

Importance: Although wait times for hip fracture surgery have been linked to mortality and are being used as quality-of-care indicators worldwide, controversy exists about the duration of the wait that leads to complications. Objective: To use population-based wait-time data to identify the optimal time window in which to conduct hip fracture surgery before the risk of complications increases. Design, Setting, and Participants: Population-based, retrospective cohort study of adults undergoing hip fracture surgery between April 1, 2009, and March 31, 2014, at 72 hospitals in Ontario, Canada. Risk-adjusted restricted cubic splines modeled the probability of each complication according to wait time. The inflection point (in hours) when complications began to increase was used to define early and delayed surgery. To evaluate the robustness of this definition, outcomes among propensity-score matched early and delayed surgical patients were compared using percent absolute risk differences (RDs, with 95% CIs). Exposure: Time elapsed from hospital arrival to surgery (in hours). Main Outcomes and Measures: Mortality within 30 days. Secondary outcomes included a composite of mortality or other medical complications (myocardial infarction, deep vein thrombosis, pulmonary embolism, and pneumonia). Results: Among 42 230 patients with hip fracture (mean [SD] age, 80.1 years [10.7], 70.5% women) who met study entry criteria, overall mortality at 30 days was 7.0%. The risk of complications increased when wait times were greater than 24 hours, irrespective of the complication considered. Compared with 13 731 propensity-score matched patients who received surgery earlier, 13 731 patients who received surgery after 24 hours had a significantly higher risk of 30-day mortality (898 [6.5%] vs 790 [5.8%]; % absolute RD, 0.79; 95% CI, 0.23-1.35) and the composite outcome (1680 [12.2%]) vs 1383 [10.1%]; % absolute RD, 2.16; 95% CI, 1.43-2.89). Conclusions and Relevance: Among adults undergoing hip fracture surgery, increased wait time was associated with a greater risk of 30-day mortality and other complications. A wait time of 24 hours may represent a threshold defining higher risk.

The True Recurrence Rate and Factors Predicting Recurrent Instability After Nonsurgical Management of Traumatic Primary Anterior Shoulder Dislocation: A Systematic Review.

PURPOSE: To (1) define the cumulative recurrence rate after primary anterior shoulder dislocation in Level I and II comparative studies and (2) to pool risk ratios for common risk factors to provide a clinically practical hierarchy of modifiable and nonmodifiable risk factors for recurrence. METHODS: Level I and II prognostic studies were identified using the electronic databases CINAHL, Embase, and MEDLINE from inception to December 2014. Included studies (n = 15) had recurrent dislocation as the main outcome, and a minimum 2-year follow-up. The cumulative odds ratio of prognostic factors was calculated where appropriate. Bias was assessed in each study using the Quality in Prognosis Studies (QUIPS) tool. RESULTS: The reported rate of recurrence ranged from 19% to 88% (pooled overall = 21%; pooled Level I only = 47%). The pooled time to recurrence was 10.8 months (standard deviation 0.42). Male sex (n = 6 studies) conferred a 2.68 (1.66-4.31; P < .001) and patient age <20 years (n = 4 studies) conferred a 12.76 (5.77-28.2; P < .001; vs >20 years) increased odds of recurrence. An associated greater tuberosity fracture (n = 7 studies) decreased the odds of recurrence by 3.8 times (2.94-5.00; P < .001). The quality of evidence was moderate for age, low for sex, and very low for all other prognostic variables. CONCLUSIONS: The pooled rate of recurrence after primary anterior shoulder instability was found to be 21% among moderate- to high-quality prognostic studies. Male sex and younger age predicted a significantly higher risk of recurrent instability (approaching 80%), whereas concurrent fracture of the greater tuberosity significantly decreased the risk of subsequent recurrent dislocation. However, considering the quality of available evidence for these predictors, there remains a clear need for further high-quality prospective studies. LEVEL OF EVIDENCE: Level II, systematic review of Level I and II prognostic studies.

Use of an Objective Structured Assessment of Technical Skill After a Sports Medicine Rotation.

PURPOSE: The purpose of this study was to determine if the use of an Objective Structured Assessment of Technical skill (OSATS), using dry models, would be a valid method of assessing residents' ability to perform sports medicine procedures after training in a competency-based model. METHODS: Over 18 months, 27 residents (19 junior [postgraduate year (PGY) 1-3] and 8 senior [PGY 4-5]) sat the OSATS after their rotation, in addition to 14 sports medicine staff and fellows. Each resident was provided a list of 10 procedures in which they were expected to show competence. At the end of the rotation, each resident undertook an OSATS composed of 6 stations sampled from the 10 procedures using dry models-faculty used the Arthroscopic Surgical Skill Evaluation Tool (ASSET), task-specific checklists, as well as an overall 5-point global rating scale (GRS) to score each resident. Each procedure was videotaped for blinded review. RESULTS: The overall reliability of the OSATS (0.9) and the inter-rater reliability (0.9) were both high. A significant difference by year in training was seen for the overall GRS, the total ASSET score, and the total checklist score, as well as for each technical procedure (P < .001). Further analysis revealed a significant difference in the total ASSET score between junior (mean 18.4, 95% confidence interval [CI] 16.8 to 19.9) and senior residents (24.2, 95% CI 22.7 to 25.6), senior residents and fellows (30.1, 95% CI 28.2 to 31.9), as well as between fellows and faculty (37, 95% CI 36.1 to 27.8) (P < .05). CONCLUSIONS: The results of this study show that an OSATS using dry models shows evidence of validity when used to assess performance of technical procedures after a sports medicine rotation. However, junior residents were not able to perform as well as senior residents, suggesting that overall surgical experience is as important as intensive teaching. CLINICAL RELEVANCE: As postgraduate medical training shifts to a competency-based model, methods of assessing performance of technical procedures become necessary.

Maximum load to failure and tensile displacement of an all-suture glenoid anchor compared with a screw-in glenoid anchor.

PURPOSE: The purpose of this study was to evaluate the biomechanical behavior of an all-suture glenoid anchor in comparison with a more conventional screw-in glenoid anchor, with regard to maximum load to failure and tensile displacement. METHODS: All mechanical testing was performed using an Instron ElectroPuls E1000 mechanical machine, with a 10 N pre-load and displacement rate of 10 mm/min. Force-displacement curves were generated, with calculation of maximum load, maximum displacement, displacement at 50 N and stiffness. Pretesting of handset Y-Knots in bone analog models revealed low force displacement below 60 N of force. Subsequently, three groups of anchors were tested for pull out strength in bovine bone and cadaver glenoid bone: a bioabsorbable screw-in anchor (Bio Mini-Revo, ConMed Linvatec), a handset all-suture anchor (Y-Knot, ConMed Linvatec) and a 60 N pre-tensioned all-suture anchor (Y-Knot). A total of 8 anchors from each group was tested in proximal tibia of bovine bone and human glenoids (age range 50-90). RESULTS: In bovine bone, the Bio Mini-Revo displayed greater maximum load to failure (206 ± 77 N) than both the handset (140 ± 51 N; P = 0.01) and the pre-tensioned Y-Knot (135 ± 46 N; P = 0.001); no significant difference was seen between the three anchor groups in glenoid bone. Compared to the screw-in anchors, the handset all-suture anchor displayed inferior fixation, early displacement and greater laxity in the bovine bone and cadaveric bone (P < 0.05). Pre-tensioning the all-suture anchor to 60 N eliminated this behavior in all bone models. CONCLUSIONS: Handset Y-Knots display low force anchor displacement, which is likely due to slippage in the pilot hole. Pre-tensioning the Y-Knot to 60 N eliminates this behavior. LEVEL OF EVIDENCE: I.

How to set the bar in competency-based medical education: standard setting after an Objective Structured Clinical Examination (OSCE).

BACKGROUND: The goal of the Objective Structured Clinical Examination (OSCE) in Competency-based Medical Education (CBME) is to establish a minimal level of competence. The purpose of this study was to 1) to determine the credibility and acceptability of the modified Angoff method of standard setting in the setting of CBME, using the Borderline Group (BG) method and the Borderline Regression (BLR) method as a reference standard; 2) to determine if it is feasible to set different standards for junior and senior residents, and 3) to determine the desired characteristics of the judges applying the modified Angoff method. METHODS: The results of a previous OSCE study (21 junior residents, 18 senior residents, and six fellows) were used. Three groups of judges performed the modified Angoff method for both junior and senior residents: 1) sports medicine surgeons, 2) non-sports medicine orthopedic surgeons, and 3) sports fellows. Judges defined a borderline resident as a resident performing at a level between competent and a novice at each station. For each checklist item, the judges answered yes or no for "will the borderline/advanced beginner examinee respond correctly to this item?" The pass mark was calculated by averaging the scores. This pass mark was compared to that created using both the BG and the BLR methods. RESULTS: A paired t-test showed that all examiner groups expected senior residents to get significantly higher percentage of checklist items correct compared to junior residents (all stations p < 0.001). There were no significant differences due to judge type. For senior residents, there were no significant differences between the cut scores determined by the modified Angoff method and the BG/BLR method. For junior residents, the cut scores determined by the modified Angoff method were lower than the cut scores determined by the BG/BLR Method (all p < 0.01). CONCLUSION: The results of this study show that the modified Angoff method is an acceptable method of setting different pass marks for senior and junior residents. The use of this method enables both senior and junior residents to sit the same OSCE, preferable in the regular assessment environment of CBME.

Arthroscopic Repair for Chronic Massive Rotator Cuff Tears: A Systematic Review.

PURPOSE: To systematically review the available evidence for arthroscopic repair of chronic massive rotator cuff tears and identify patient demographics, pre- and post-operative functional limitations, reparability and repair techniques, and retear rates. METHODS: Medline, Embase, the Cochrane Database of Systematic Reviews, and the Cochrane Central Register of Controlled Trials were searched to identify all clinical papers describing arthroscopic repair of chronic massive rotator cuff tears. Papers were excluded if a definition of "massive" was not provided, if the definition of "massive" was considered inappropriate by agreement between the 2 reviewers, or if patients with smaller tears were also included in the study population. Study quality and clinical outcome data were pooled and summarized. RESULTS: There were 18 papers that met the eligibility criteria; they involved 954 patients with a mean age of 63 (range, 37 to 87), 48% of whom were female. There were 5 prospective and 13 retrospective study designs. The overall study quality was poor according to the Modified Coleman Methodology Score. Of the 954 repairs, 81% were complete repairs and 19% were partial repairs. The follow-up range was between 33 and 52 months, and the mean duration between symptom onset and surgery was 24 months. Single-row repairs were performed in 56% or patients, and double-row repairs were performed in 44%. A pooled analysis demonstrated an improvement in visual analog scale from 5.9 to 1.7, active range of motion from 125° to 169°, and the Constant-Murley score from 49 to 74. The pooled retear rate was 79%. CONCLUSIONS: Arthroscopic repair of chronic massive rotator cuff tears is associated with complete repair in the majority of cases and consistently improves pain, range of motion, and functional outcome scores; however, the retear rate is high. Existing research on massive rotator cuff repair is limited to poor- to fair-quality studies. LEVEL OF EVIDENCE: Level IV, systematic review including Level IV studies.

Trans-subscapularis portal versus low-anterior portal for low anchor placement on the inferior glenoid fossa: a cadaveric shoulder study with computed tomographic analysis.

PURPOSE: The purpose of this study was to evaluate the accuracy of inserting a glenoid anchor at the 5:30 clockface position using a trans-subscapularis (TSS) portal versus a low anterior (LA) portal. METHODS: Five surgeons (T.D., J.C., C.V., D.J.O-H., J.S.T.) placed a single anchor in 20 fresh-frozen cadaveric shoulders. In each of 2 shoulders, surgeons used an LA portal to insert the anchor, whereas in 2 shoulders a TSS portal was used. Surgeons were directed to place the anchor at the 5:30 position at an angle 45° to the glenoid surface (axial plane) and passing perpendicular to the glenoid rim in the coronal plane. Shoulders were then dissected and computed tomographic (CT) scans obtained. Anchor position relative to the clockface was documented by 2 blinded assessors, as was the angle of insertion in the axial and coronal planes. Statistical significance was calculated with a Student t test for paired samples (confidence interval [CI], 95%; significance, P < .05). RESULTS: The average deviation from the 5:30 position was 48 minutes (standard deviation [SD], 31 minutes) for the LA portal (average position, 4:42 o'clock) versus 28.5 minutes (SD, 19 minutes) for the TSS group (average position, 5:02 o'clock) (P = .15). The average angle of anchor insertion in the axial plane was 67.2° (SD, 19°) for the LA portal versus 62.8° (SD, 14°) for the TSS portal (P = .49), whereas the average angle of insertion in the coronal plane was 31.3° (SD, 14°) of inferior angulation in the LA group and 14.3° (SD, 8°) of inferior angulation in the TSS group (P = .009). Of the anchors inserted, 9 of 20 (45%) showed evidence of far-cortical perforation. No difference in cortical perforation was seen between the 2 portals, with perforation more likely with anchors inserted greater than 45° in the axial plane (8 of 20) than with those inserted less than 45° (1 of 20) (P = .02). CONCLUSIONS: The use of a TSS portal improves the angle of approach to the inferior glenoid rim in comparison with an LA portal, reducing the acuity of the angle of insertion in the coronal plane. CLINICAL RELEVANCE: The TSS portal is an option for surgeons performing arthroscopic Bankart repair using anchors low on the glenoid rim.