The American Journal of Sports Medicine

Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used in the treatment of Achilles tendinopathy, but whether they have any additive clinical effect on physical rehabilitation in the early phase of tendinopathy remains unknown.

To investigate whether an initial short-term NSAID treatment added to a physical rehabilitation program in the early phase of Achilles tendinopathy would have an additive effect. We hypothesized that the combination of NSAID and rehabilitation would be superior to rehabilitation alone.

Randomized controlled trial; Level of evidence, 1.

A total of 69 patients with early phase Achilles tendinopathy (lasting <3 months) were randomly assigned to either a naproxen group (7 days of treatment; 500 mg twice daily; n = 34) or a placebo group (7 days of placebo treatment; n = 35). Both groups received an identical 12-week physical rehabilitation program. The clinical outcome of the study was evaluated using the Victorian Institute of Sports Assessment–Achilles (VISA-A) questionnaire and a numerical rating scale (NRS), and the physiological outcome was evaluated using ultrasonography, magnetic resonance imaging (MRI), and ultra-short time to echo T2* mapping MRI (UTE T2* MRI). Follow-up was performed at 1 week, 3 months, and 1 year. Time effects are presented as mean difference ± SEM.

No significant differences were found between the 2 treatment groups for any of the outcome measures at any time point (P > .05). For the VISA-A score, a significant time effect was observed between baseline and 3-month follow-up (14.9 ± 2.3; P < .0001), and at 1-year follow-up, additional improvements were observed (6.1 ± 2.3; P < .01). Furthermore, the change in VISA-A score between baseline and 3-month follow-up was greater in patients with very short symptom duration (<1 month) at baseline compared with patients who had longer symptom duration (>2 months) (interaction between groups, 11.7 ± 4.2; P < .01). Despite clinical improvements, total weekly physical activity remained lower compared with preinjury levels at 3 months (–2.7 ± 0.5 h/wk; P < .0001) and 1 year (–3.0 ± 0.5 h/wk; P < .0001). At baseline, ultrasonography showed increased thickness (0.12 ± 0.03 cm; P < .0001) and vascularity (0.3 ± 0.1 cm²; P < .005) on the tendinopathic side compared with the contralateral side, but no changes over time were observed for ultrasonography, MRI, or UTE T2* MRI results.

Clinical symptoms in early tendinopathy improved with physical rehabilitation, but this improvement was not augmented with the addition of NSAID treatment. Furthermore, this clinical recovery occurred in the absence of any measurable structural alterations. Finally, clinical improvements after a physical rehabilitation program were greater in patients with very short symptom duration compared with patients who had longer symptom duration.

NCT03401177 (ClinicalTrials.gov identifier) and BFH-2016-019 (Danish Data Protection Agency)

Although several arthroscopic surgical techniques for the treatment of chronic ankle instability (CAI) have been introduced recently, the effect of inferior extensor retinaculum (IER) augmentation remains unclear.

To compare the clinical outcomes after arthroscopic anterior talofibular ligament (ATFL) repair according to whether additional IER augmentation was performed or not.

Cohort study; Level of evidence, 3.

We performed a retrospective review of consecutive patients who underwent arthroscopic ATFL repair surgery for CAI between 2016 and 2018. The mean age of the patients was 35.2 years (range, 19-51 years), and the mean follow-up period was 32.6 months (range, 24-48 months). Patients were divided into 2 groups according to the surgical technique used for CAI: arthroscopic ATFL repair (group A; n = 37) and arthroscopic ATFL repair with additional IER augmentation (group R; n = 45). The pain visual analog scale, American Orthopaedic Foot & Ankle Society score, Foot and Ankle Outcome Score, and the Karlsson Ankle Function Score were measured as subjective outcomes, and posturographic analysis was performed using a Tetrax device as an objective outcome. Radiologic outcome evaluations were performed preoperatively and at 2 years postoperatively using stress radiographs and axial view magnetic resonance imaging (MRI).

Out of 101 patients, 19 (18.5%) were excluded per the exclusion criteria, and 82 were evaluated. We identified 6 retears (7.3%) based on postoperative MRI evaluation. All patients who had ATFL retear on MRI (8.1% [3/37] in group A and 6.7% [3/45] in group R) demonstrated recurrent CAI with functional discomfort and anterior displacement >3 mm as compared with the intact contralateral ankle. All clinical scores and posturography results were improved after surgery in both groups (P < .001). However, there were no significant differences in the clinical results and radiologic findings between the groups.

The clinical and radiologic outcomes of patients with CAI improved after all-inside arthroscopic ATFL repair. However, additional IER augmentation after arthroscopic ATFL repair did not guarantee better clinical outcomes.

The goal of treatment for a proximal hamstring avulsion (PHA) is an objectively restored muscle and a subjectively satisfied, pain-free patient at follow-up. Different self-reported and performance-based outcome measures have been used to evaluate recovery, but their validity is poorly investigated.

To investigate (1) the correlation between the commonly used self-reported outcome measurements, the Perth Hamstring Assessment Tool (PHAT) and the Lower Extremity Functional Scale (LEFS); (2) to what extent these scores can be explained by physical dysfunction as measured by performance-based tests; (3) whether performance-based tests can discriminate between the injured and uninjured extremity; and (4) which activity limitations are perceived by patients several years after the injury.

Cohort study (Diagnosis); Level of evidence, 3.

We included a consecutive series of patients treated for or diagnosed with PHA in our department between 2007 and 2016 having at least 2 tendons avulsed from the ischial tuberosity. Participants attended 2 study visits, answered questionnaires (PHAT, LEFS, and Patient-Specific Functional Scale [PSFS]), and performed physical performance–based tests (single-leg hop tests, single–step down test, and isometric and isokinetic strength tests).

A total of 50 patients were included (26 men [52%], 24 women [48%]; mean age, 50.9 years [SD, 9.8 years]). The mean follow-up time was 5.5 years (SD, 2.7 years), and 74% had been surgically treated. The correlation between PHAT and LEFS was strong (r = 0.832) and statistically significant (P < .001). Seven of the performance-based tests exhibited a statistically significant but weak correlation with LEFS (0.340-0.488) and 3 of the tests to PHAT (–0.304 to 0.406). However, only peak torque could significantly discriminate between the extremities. The activity limitation most commonly mentioned in PSFS was running (16 patients [32%]).

Although PHAT and LEFS correlated strongly, the correlations between functional tests and the patient-reported outcome scores were weak, and most functional tests failed to discriminate between the injured and uninjured lower extremity in patients with PHA 5 years after injury. In general, patients alleged few activity limitations, but running difficulty was a common sequela after PHA.

Inguinal disruption and femoroacetabular impingement (FAI) are well-recognized sources of groin pain in athletes; however, the relationship between inguinal disruption and FAI remains unclear. In cases of dual pathology, where both entities coexist, there is no definitive consensus regarding which pathology should be prioritized for treatment in the first instance.

(1) To examine the 2-year effectiveness and clinical outcome in athletes presenting with dual pathology in which the FAI component alone was treated with arthroscopic deformity correction. (2) To compare 2-year patient-reported outcome measures between athletes undergoing only hip arthroscopy (HA) and athletes undergoing groin repair and HA.

Cohort study; Level of evidence, 3.

All patients undergoing HA for the treatment of FAI with concomitant clinical signs of inguinal disruption at initial consultation were between 2010 and 2016 were included in this study. Inclusion criteria were male sex, age <40 years, and involvement in competitive sporting activity. Athletes with previous HA on the symptomatic side, Tönnis grade >1, or lateral center-edge angle <25° were excluded. Revision HA or subsequent groin surgery was documented. Outcome evaluation consisted of validated patient-reported outcome measures (modified Harris Hip Score; University of California, Los Angeles Activity Scale; 36-Item Short Form Health Survey; Western Ontario and McMaster Universities Osteoarthritis Index) completed preoperatively and a minimum 2 years postoperatively. The minimal clinically important difference was assessed by using a distribution-based technique (SD, 0.5) and an anchor-based technique (percentage of possible improvement). Level of satisfaction and return to play were assessed.

A total of 113 cases of dual pathology were included in 91 patients with a mean ± SD age of 26.3 ± 5.1 years. The index surgical procedure was HA for 104 cases (92%) and groin repair for 9 (8%). For patients undergoing HA as the index procedure, 98.1% (102/104 cases) were successfully followed up to establish survivorship. In 89.2% (91/102 cases), no additional groin surgery was required. In 11 cases (10.8%), additional groin surgery was required for persisting inguinal-related groin pain. At 2 years after the operation, there was no difference for any patient-reported outcome measure (P > .099), improvement from baseline (P > .070), or proportion of cases achieving the minimal clinically important difference (P > .120) between the HA-only group and the group undergoing HA and groin repair at any stage. There was also no difference between groups in terms of return-to-play rate (P = .509) or levels of satisfaction (pain, P = .204; performance, P = .345).

In patients with dual pathology, treatment of the FAI component alone using arthroscopic hip surgery results in a successful outcome without need for groin repair in 89.2% of cases. No statistical difference in clinical outcome 2 years after surgery was observed between athletes undergoing 1 procedure (HA alone) and those undergoing 2 procedures (HA and groin repair at any stage).

There is a paucity in the literature reporting patient-reported outcome (PRO) scores and the minimal clinically important difference (MCID) after revision hip arthroscopic surgery with circumferential labral reconstruction.

To report minimum 2-year PRO scores and the rate of achieving the MCID in patients who underwent revision hip arthroscopic surgery with circumferential labral reconstruction in the setting of irreparable labral tears.

Case series; Level of evidence, 4.

Data were retrospectively reviewed for all patients who underwent revision hip arthroscopic surgery between February 2016 and November 2017. Patients were included if they had undergone circumferential labral reconstruction and had preoperative and postoperative scores for the modified Harris Hip Score (mHHS), Non-Arthritic Hip Score (NAHS), Hip Outcome Score Sport-Specific Subscale (HOS-SSS), International Hip Outcome Tool (iHOT-12), 12-Item Short Form Health Survey physical and mental components (SF-12 P and SF-12 M, respectively), Veterans RAND 12-Item Health Survey physical and mental components (VR-12 P and VR-12 M, respectively), and visual analog scale (VAS) for pain. Exclusion criteria were Tönnis grade >1, Legg-Calve-Perthes disease, slipped capital femoral epiphysis, fractures, hip dysplasia, or revision labral treatment different from circumferential labral reconstruction. The MCID was calculated. Secondary surgical procedures were documented.

A total of 26 hips (26 patients; 61.5% female) were included. The mean age and body mass index were 33.2 ± 10.4 years and 25.5 ± 4.9, respectively. Significant improvements were reported for the mHHS (17.0 ± 19.5; P = .0002), NAHS (17.9 ± 16.7; P < .0001), HOS-SSS (21.7 ± 23.1; P = .0005), VAS (–2.2 ± 3.0; P = .006), iHOT-12 (25.8 ± 32.5; P = .0007), SF-12 P (8.5 ± 11.2; P = .001), and VR-12 P (8.9 ± 11.6; P = .001). Rates of meeting the MCID for the mHHS, NAHS, HOS-SSS, iHOT-12, and VAS were 76.9%, 80.0%, 65.0%, 62.5%, and 69.2%, respectively. No case of re-revision arthroscopic surgery was documented, but 1 case of conversion to total hip arthroplasty was documented at 38.6 months.

In the setting of revision hip arthroscopic surgery and irreparable labral tears, circumferential labral reconstruction resulted in significant improvements in all PRO and VAS scores at a minimum 2-year follow-up with a high rate of achieving the MCID.

Pertrochanteric calcifications can be found in patients with greater trochanteric pain syndrome (GTPS). A systematic description of the types and prevalence of these calcifications has not been undertaken. Furthermore, there is conflicting evidence regarding their association with abductor tendon injuries.

(1) To describe the various types and prevalence of pertrochanteric calcifications in patients presenting for the surgical management of recalcitrant GTPS. (2) To evaluate the association of the various calcifications with intraoperatively diagnosed hip abductor tendon injuries, including tendinosis, partial-thickness tears, and full-thickness tears.

Cross-sectional study; Level of evidence, 3.

Patients undergoing surgical management for GTPS, in isolation or as an ancillary procedure during hip arthroscopy for femoroacetabular impingement, between April 2008 and February 2020 were included. Of these, 85 procedures were isolated treatment of GTPS and the remaining 628 were ancillary to hip arthroscopy. Radiographs were scrutinized for the presence of pertrochanteric calcifications. The hip abductor tendon status was intraoperatively classified as intact, partial-thickness tear, or full-thickness tear. The prevalence and correlation of the various radiographic findings in relation to the intraoperatively classified tendon condition were analyzed via the odds ratio (OR).

Surgery was performed on 713 hips with recalcitrant GTPS. No tear was found in 340 hips (47.7%), 289 hips (40.5%) had a partial-thickness tear, and 84 hips (11.8%) had a full-thickness tear. Radiographically, 102 hips (14.3%) demonstrated proximally directed enthesophytes, and 34 (4.8%) had distally directed enthesophytes. In addition, 75 hips (10.5%) had amorphous calcifications, 47 (6.6%) had isolated ossicles, and 110 (15.4%) had surface irregularities. The presence of any calcification was associated with partial-thickness tears (OR, 1.67 [95% CI, 1.21-2.21]; P = .002) and full-thickness tears (OR, 6.40 [95% CI, 3.91-10.47]; P < .001). Distally directed enthesophytes (OR, 10.18 [95% CI, 3.08-33.63]; P < .001) and proximally directed enthesophytes (OR, 8.69 [95% CI, 4.66-16.21]; P < .001) were the findings with the highest OR for the presence of any type of tear. Distally directed enthesophytes were the findings with the highest OR for a full-thickness tear (OR, 15.79 [95% CI, 7.55-33.06]; P < .001). Isolated ossicles were the findings with the highest OR for a partial-thickness tear (OR, 1.73 [95% CI, 0.96-3.13]; P = .070).

Pertrochanteric calcifications were common radiographic findings in patients with GTPS and can help guide management in these patients. Proximally and distally directed enthesophytes were strong predictors for the presence of a hip abductor tendon tear, and specifically a full-thickness tear, and increasing size of the findings was associated with more severe tendon injuries.

Septic arthritis (SA) after anterior cruciate ligament reconstruction (ACLR) is a rare yet severe complication. The samples in previous studies have been small and without nationwide coverage, making analysis uncertain with a risk of bias. Conclusions to recommend preventive measures are therefore difficult to draw, and it has not been possible to perform a comprehensive risk factor analysis.

To study the incidence of SA after ACLR in a large, nationwide population and to study the risk factors for SA after ACLR.

Case-control study; Level of evidence, 3.

All ACLRs, primary and revision, in the Swedish Knee Ligament Registry between 2006 and 2013 were linked with data from the Swedish National Board of Health and Welfare. The incidence of SA events was determined using entries from the day of surgery until 90 days postoperatively based on diagnosis codes and the prescription of antibiotics. All events of SA were verified via a review of medical records. Risk factors were analyzed based on data from the registries. Descriptive statistics were used to describe the findings, while logistic regression analysis was used for the risk analysis.

The cohort consisted of 26,014 primary and revision ACLRs. During the study period, 298 events of SA (1.1%) were identified. The high-volume units (≥500 ACLRs during the study period) had a distribution of SA between 2 and 47 (0.2%-2.9%). Independent risk factors of SA were male sex (OR, 1.65; 95% CI, 1.28-2.13), operating time ≥70 minutes (OR, 1.83; 95% CI, 1.42-2.36), hamstring tendon autograft (OR, 2.23; 95% CI, 1.21-4.08), and clindamycin as perioperative antibiotic prophylaxis (OR, 1.94; 95% CI, 1.10-3.41).

The incidence of SA after ACLR in this nationwide cohort was 1.1%. Male sex, hamstring tendon autografts, and a longer operating time were all independent risk factors for SA. The use of clindamycin as perioperative antibiotic prophylaxis was a risk factor compared with the use of cloxacillin. Some high-volume units had a very low infection rate (0.2%).

Anterior cruciate ligament reconstructions (ACLRs) fail at an alarmingly high rate in young active individuals. The Multicenter Orthopaedic Outcomes Network (MOON) knee group has developed an autograft risk calculator that uses patient characteristics and lifestyle to predict the probability of graft rupture if the surgeon uses a hamstring tendon (HT) or a bone–patellar tendon–bone (BPTB) graft to reconstruct the ligament. If validated, this risk calculator can be used during the shared decision-making process to make optimal ACLR autograft choices and reduce rupture rates. The STABILITY 1 randomized clinical trial offers a large, rigorously collected data set of similar young active patients who received HT autograft with or without lateral extra-articular tenodesis (LET) for ACLR.

The purpose was to validate the ACLR graft rupture risk calculator in a large external data set and to investigate the utility of BPTB and LET for ACLR. We hypothesized that the risk calculator would maintain adequate discriminative ability and calibration in the external STABILITY 1 data set when compared with the initial MOON development data set.

Cohort study (diagnosis); Level of evidence, 1.

The model predictors for the risk calculator include age, sex, body mass index, sport played at the time of injury, Marx Activity Score, preoperative knee laxity, and graft type. The STABILITY 1 trial data set was used for external validation. Discriminative ability, calibration, and diagnostic test validity of the model were assessed. Finally, predictor strength in the initial and validation samples was compared.

The model showed acceptable discriminative ability (area under the curve = 0.73), calibration (Brier score = 0.07), and specificity (85.3%) to detect patients who will experience a graft rupture. Age, high-grade preoperative knee laxity, and graft type were significant predictors of graft rupture in young active patients. BPTB and the addition of LET to HT were protective against graft rupture versus HT autograft alone.

The MOON risk calculator is a valid predictor of ACLR graft rupture and is appropriate for clinical practice. This study provides evidence supporting the idea that isolated HT autografts should be avoided for young active patients undergoing ACLR.

NCT00463099 (MOON); NCT02018354 (STABILITY 1) (ClinicalTrials.gov identifiers)

Anterior cruciate ligament (ACL) tears are common in contact athletics and have a significant effect on the athletic performance and well-being of affected players. The prevalence, timing, and characteristics of ACL tears in National Football League (NFL) athletes are lacking.

To define the epidemiology of ACL tears among NFL athletes.

Descriptive epidemiology study.

This retrospective study includes all ACL injuries entered into the NFL injury database through the centralized leaguewide electronic health record system for the 2015-2019 seasons.

A total of 314 ACL injuries occurred during the 5-year study period, with a mean of 62 per year. The overall 1-season injury risk of an NFL player sustaining an ACL injury was 1.9% (95% CI, 1.7%-2.1%). Most ACL injuries occurred during games (n = 199), with a higher rate observed in the preseason games as compared with the regular season games (6.1 vs 2.7 per 10,000 player-plays; P < .01). NFL players with ≤3 of experience had a higher preseason injury rate (9.57 ACL tears per 1000 player-seasons) than those with ≥4 years of experience (5.12 ACL tears per 1000 player-seasons; P < .01). NFL athletes playing on special teams had the highest rate of ACL injuries (7.6 per 10,000 player-plays) in comparison with all other player positions.

ACL injury incidence was fairly consistent across all years studied and occurred more frequently in players with ≤3 years of NFL experience. Tears were more common during games, special teams play, and the preseason.

Female soccer players are particularly susceptible to anterior cruciate ligament (ACL) injuries, accounting for 16% to 43% of the injury burden during the season. Despite the advancements in injury prevention programs, the rate of ACL injuries continues to rise.

To provide a comprehensive description of the mechanisms, situational pattern, and biomechanics of ACL injuries in women’s soccer.

Case series; Level of evidence, 4.

We identified 57 consecutive ACL injuries that occurred in matches of 6 top female leagues across 3 seasons (2017-2020). A total of 35 (61%) injury videos were analyzed for the mechanism and situational pattern, while biomechanical analysis was possible in 29 cases. Three independent reviewers evaluated each video. The distribution of ACL injuries according to month, timing within the match, and field location at the time of injury was also reported.

In the 35 injury videos, there were 19 (54%) noncontact injuries, 12 (34%) indirect contact injuries, and 4 (11%) direct contact injuries. We identified 3 main situations in players who suffered a noncontact/indirect contact injury: (1) pressing and tackling (n = 18), (2) regaining balance after kicking (n = 7), and (3) being tackled (n = 4). Biomechanical analysis indicated multiplanar mechanisms with frequent knee valgus loading (88%). Additionally, 64% of injuries occurred in the first half of matches and most frequently within the first 30 minutes.

Female athletes showed remarkable similarities with elite male players in terms of the ACL mechanism and situational pattern of injury, and 88% of injuries involved no direct contact to the knee, with noncontact injuries being highly prevalent. Injuries occurred during 3 main situations, with accompanying alterations in multiplanar biomechanics. Interventions aimed at reducing ACL injuries in women’s soccer should consider high-intensity defensive play at the beginning of a match. Instruction in the 3 main situations should be applied alongside appropriate neuromuscular training interventions.

Lateral extra-articular tenodesis (LET) in combination with anterior cruciate ligament (ACL) reconstruction (ACLR) has been proposed to improve residual rotatory knee instability in patients having ACL deficiency.

The purpose was to compare the effects of isolated ACLR (iACLR) versus LET in combination with ACLR (ACLR+LET) on in vivo kinematics during downhill running. It was hypothesized that ACLR+LET would reduce the internal rotation of the reconstructed knee in comparison with iACLR.

Controlled laboratory study.

A total of 18 patients with ACL deficiency were included. All participants were randomly assigned to receive ACLR+ LET or iACLR during surgery. Six months and 12 months after surgery, knee joint motion during downhill running was measured using dynamic biplane radiography and a validated registration process that matched patient-specific 3-dimensional bone models to synchronized biplane radiographs. Anterior tibial translation (ATT; positive value means “anterior translation”) and tibial rotation (TR) relative to the femur were calculated for both knees. The side-to-side differences (SSDs) in kinematics were also calculated (operated knee–contralateral healthy knee). The SSD value was compared between ACLR+LET and iACLR groups using a Mann-Whitney U test.

At 6 months after surgery, the SSD of ATT in patients who had undergone ACLR+LET (–1.9 ± 2.0 mm) was significantly greater than that in patients who had undergone iACLR (0.9 ± 2.3 mm) at 0% of the gait cycle (foot strike) (P = .031). There was no difference in ATT 12 months after surgery. Regarding TR, there were no differences between ACLR+LET and iACLR at either 6 months (P value range, .161-.605) or 12 months (P value range, .083-.279) after surgery.

LET in combination with ACLR significantly reduced ATT at the instant of foot strike during downhill running at 6 months after surgery. However, this effect was not significant at 12 months after surgery. The addition of LET to ACLR had no effect on TR at both 6 and 12 months after surgery.

LET in combination with ACLR may stabilize sagittal knee motion during downhill running in the early postoperation phase, but according to this study, it has no effect on 12-month in vivo kinematics.

NCT02913404 (ClinicalTrials.gov identifier)

Ramp lesions are defined as a particular type of injury within the posterior horn of the medial meniscus and its meniscocapsular attachments. Five subtypes have been described: type 1, meniscocapsular lesion; type 2, partial superior lesion; type 3, partial inferior lesion or hidden type; type 4, complete tear in the red zone; and type 5, complete double tear.

(1) To determine the prevalence of different subtypes of ramp lesions in patients undergoing arthroscopic anterior cruciate ligament reconstruction (ACLR). (2) To describe the characteristics of ramp lesions based on imaging and diagnostic arthroscopy.

Cross-sectional study; Level of evidence, 3.

All patients who underwent arthroscopic ACLRs between November 2015 and November 2018 by 2 senior surgeons at 1 institution were evaluated retrospectively (1) to describe the subtypes of ramp lesions diagnosed intraoperatively using transnotch arthroscopic exploration of the posteromedial compartment and (2) to look for any factors significantly associated with these subtypes. The following parameters were studied: demographics; history and clinical findings including time between injury and surgery, side-to-side laxity, and pivot shift; lesions missed on magnetic resonance imaging (MRI) scans and medial proximal tibial bone contusion visible on MRI scans; and arthroscopic confirmation of ramp lesion (ie, prevalence), associated lateral meniscal tear, or medial chondral tear.

Out of 2156 primary or revision arthroscopic reconstructions, 334 ramp lesions were confirmed, giving a prevalence of 15.5%. The subtype distribution was as follows: type 1, 47.9%; type 2, 4.8%; type 3, 11.4%; type 4, 28.7%; type 5, 7.2%. Multivariate analysis showed that gross pivot shift was significantly associated with complete ramp tears (odds ratio, 4.8; 95% CI, 1.7-17.2). Hidden lesions (type 3, inferior partial tear in the red zone) were the most likely to be missed on preoperative MRI (45.9%).

In a population undergoing ACLR, the prevalence of ramp lesions was 15.5%. Among the subtypes of ramp lesion, the most common was a meniscocapsular junction tear (type 1). Partial inferior tears (type 3) were the most likely to be missed on preoperative MRI scans. Gross pivot shift was significantly associated with complete ramp tears (types 1, 4, and 5).

Anterior cruciate ligament (ACL) tears represent 13% of knee injuries in children. Medial meniscal tears are commonly associated with ACL ruptures. Ramp lesions correspond to posterior meniscocapsular tears of the medial meniscus. Depending on the study, the prevalence of ramp lesions is inconsistent.

To describe the prevalence of ramp lesions in children and adolescents and to investigate the sensitivity of magnetic resonance imaging (MRI) for diagnosing such lesions.

Cohort study (Diagnosis); Level of evidence, 3.

We analyzed videos from arthroscopic ACL reconstruction (ACLR) in children. During these procedures, we systematically looked for potential ramp lesions. To do so, an arthroscope was passed through the intercondylar notch to visualize the posteromedial compartment. A needle was introduced at the site of a posteromedial portal to unfold the meniscocapsular junction to reveal any hidden meniscal tear. Surgical procedures were performed by 2 senior surgeons. Videos were blindly analyzed by a third surgeon. Preoperative MRIs were screened by 2 blinded, independent senior radiologists to look specifically for ramp lesions.

Videos of 50 consecutive arthroscopic ACLRs concerning 32 boys and 18 girls were analyzed. Mean age at surgery was 14.2 years (range, 8.5-17.6 years). A total of 14 ramp lesions (28%) in 8 boys and 6 girls were identified. In addition, there were 22 tears of the meniscal body in 20 patients (40%). Arthroscopic and MRI findings did not correlate. Among 14 arthroscopically diagnosed ramp lesions, only 8 were detected on the MRI. Conversely, 12 patients had a ramp lesion detected on the MRI, which could not be confirmed intraoperatively. The sensitivity of MRI was 57% and the positive predictive value was 40%.

A meniscal ramp lesion was present in 14 of 50 children (28%) undergoing ACLR. MRI has a low sensitivity for diagnosis of ramp lesions in children. Careful exploration of the posteromedial compartment is strongly recommended. Overlooking such lesions during ACLR may contribute to ongoing instability and higher re-rupture rates in these young patients.

In contrast to the majority of existing techniques for reconstruction of the medial patellofemoral ligament (MPFL), the technique described in this article uses the adductor magnus muscle tendon to gain a flat, broad graft, leaving its distal femoral insertion intact, and does not require drilling within or near the femoral physis. It also allows for soft tissue patellar fixation and could facilitate anatomic MPFL reconstruction in skeletally immature patients.

To evaluate the anatomic and structural properties of the native MPFL and the adductor tendon (AT), followed by biomechanical evaluation of the proposed reconstruction.

Descriptive laboratory study.

The morphological and topographical features of the AT and MPFL were evaluated in 12 fresh-frozen cadaveric knees. The distance between the distal insertion of the AT on the adductor tubercle and the adductor hiatus, as well as the desired length of the graft, was measured to evaluate this graft’s application potential. Load-to-failure tests were performed to determine the biomechanical properties of the proposed reconstruction construct. The construct was placed in a uniaxial testing machine and cyclically loaded 500 times between 5 and 50 N, followed by load to failure, to measure the maximum elongation, stiffness, and maximum load.

The mean ± SD length of the AT was 12.6 ± 1.5 cm, and the mean distance between the insertion on the adductor tubercle and adductor hiatus was 10.8 ± 1.3 cm, exceeding the mean desired length of the graft (7.5 ± 0.5 cm) by 3.3 ± 0.7 cm. The distal insertion of the AT was slightly proximal and posterior to the insertion of the MPFL. The maximum elongation after cyclical loading was 1.9 ± 0.4 mm. Ultimately, the mean stiffness and load to failure were 26.2 ± 7.6 N/mm and 169.7 ± 19.2 N, respectively. The AT graft failed at patellar fixation in 2 of the initially tested specimens and at the femoral insertion in the remaining 10.

The described reconstruction using the AT has potential for MPFL reconstruction. The AT graft presents a graft of significant volume, beneficial anatomic topography, and adequate tensile properties in comparison with the native MPFL following the data from previously published studies.

Given its advantageous anatomic relationship as an application that avoids femoral drilling and osseous patellar fixation, the AT may be considered a graft for MPFL reconstruction in skeletally immature patients.

When comprehensive arthroscopic management (CAM) for glenohumeral osteoarthritis fails, total shoulder arthroplasty (TSA) may be needed, and it remains unknown whether previous CAM adversely affects outcomes after subsequent TSA.

To compare the outcomes of patients with glenohumeral osteoarthritis who underwent TSA as a primary procedure with those who underwent TSA after CAM (CAM-TSA).

Cohort study; Level of evidence, 3.

Patients younger than 70 years who underwent primary TSA or CAM-TSA and were at least 2 years postoperative were included. A total of 21 patients who underwent CAM-TSA were matched to 42 patients who underwent primary TSA by age, sex, and grade of osteoarthritis. Intraoperative blood loss and surgical time were assessed. Patient-reported outcome (PRO) scores were collected preoperatively and at final follow-up including the American Shoulder and Elbow Surgeons (ASES) score, Single Assessment Numeric Evaluation (SANE), shortened version of Disabilities of the Arm, Shoulder and Hand (QuickDASH), 12-Item Short Form Health Survey Physical Component Summary (SF-12 PCS), visual analog scale, and patient satisfaction. Revision arthroplasty was defined as failure.

Of 63 patients, 56 of them (19 CAM-TSA and 37 primary TSA; 88.9%) were available for follow-up. There were 16 female (28.6%) and 40 male (71.4%) patients with a mean age of 57.8 years (range, 38.8-66.7 years). There were no significant differences in intraoperative blood loss (P > .999) or surgical time (P = .127) between the groups. There were 4 patients (7.1%) who had failure, and failure rates did not differ significantly between the CAM-TSA (5.3%; n = 1) and primary TSA (8.1%; n = 3) groups (P > .999). Additionally, 2 patients underwent revision arthroplasty because of trauma. A total of 50 patients who did not experience failure (17 CAM-TSA and 33 primary TSA) completed PRO measures at a mean follow-up of 4.8 years (range, 2.0-11.5 years), with no significant difference between the CAM-TSA (4.4 years [range, 2.1-10.5 years]) and primary TSA (5.0 years [range, 2.0-11.5 years]) groups (P = .164). Both groups improved significantly from preoperatively to postoperatively in all PRO scores (P < .05). No significant differences in any median PRO scores between the CAM-TSA and primary TSA groups, respectively, were seen at final follow-up: ASES: 89.9 (interquartile range [IQR], 74.9-96.6) versus 94.1 (IQR, 74.9-98.3) (P = .545); SANE: 84.0 (IQR, 74.0-94.0) versus 91.5 (IQR, 75.3-99.0) (P = .246); QuickDASH: 9.0 (IQR, 3.4-27.3) versus 9.0 (IQR, 5.1-18.1) (P = .921); SF-12 PCS: 53.8 (IQR, 50.1-57.1) versus 49.3 (IQR, 41.2-56.5) (P = .065); and patient satisfaction: 9.5 (IQR, 7.3-10.0) versus 9.0 (IQR, 5.3-10.0) (P = .308).

Patients with severe glenohumeral osteoarthritis who failed previous CAM benefited similarly from TSA compared with patients who opted directly for TSA.

Double-row (DR) and transosseous-equivalent (TOE) techniques for rotator cuff repair offer more stability and promote better tendon healing compared with single-row (SR) repairs and are preferred by many surgeons. However, they can lead to more disastrous retear patterns with failure at the medial anchor row or the musculotendinous junction. The biomechanics of medial cuff failure have not been thoroughly investigated thus far.

To investigate the intratendinous strain distribution within the supraspinatus tendon depending on repair technique.

Controlled laboratory study.

Twelve fresh-frozen cadaveric shoulders were used. The intratendinous strain within the supraspinatus tendon was analyzed in 2 regions—(1) at the footprint at the greater tuberosity and (2) medial to the footprint up to the musculotendinous junction—using a high-resolution 3-dimensional camera system. Testing was performed at submaximal loads of 40 N, 60 N, and 80 N for intact tendons, after SR repair, after DR repair, and after TOE repair.

The tendon strain of the SR group differed significantly in both regions from that of the intact tendons and the TOE group at 40 N (P≤ .043) and from the intact tendons, the DR group, and the TOE group at 60 N and 80 N (P≤ .048). SR repairs showed more tendon elongation at the footprint and less elongation medial to the footprint. DR and TOE repairs did not provide significant differences in tendon strain when compared with the intact tendons. However, the increase in tendon strain medial to the footprint from 40 N to 80 N was significantly more pronounced in the DR and TOE group (P≤ .029).

While DR and TOE repair techniques more closely reproduced the strains of the supraspinatus tendon than did SR repair in a cadaveric model, they showed a significantly increased tendon strain at the musculotendinous junction with higher loads in comparison with the intact tendon.

DR and TOE rotator cuff reconstructions lead to a more anatomic tendon repair. However, their use has to be carefully evaluated whenever tendon quality is diminished, as they lead to a more drastic increase in tendon strain medial to the footprint, putting these repairs at risk of medial cuff failure.

In a study from our institution, ultrasonic percutaneous tenotomy of the brevis and the common extensor tendon for recalcitrant lateral elbow tendinopathy showed excellent safety profiles, high tolerability, efficiency, sustained pain relief, functional improvement, and sonographic evidence of tissue healing in 20 patients at 3 years’ follow-up.

To explore the long-term clinical and sonographic results of ultrasonic percutaneous tenotomy of the brevis and the common extensor tendon.

Case series; Level of evidence, 4.

The same cohort of 20 patients was recalled after 7 years, and visual analog scale (VAS) for pain and Disabilities of the Arm, Shoulder and Hand (DASH) scores, need for secondary intervention, and overall satisfaction were assessed. They were also reassessed using ultrasound imaging of the brevis and the common extensor tendon to evaluate tendon hypervascularity, tendon thickness, and the progress or the recurrence of the hypoechoic scar tissue.

We successfully scored 19 patients and performed ultrasound on 16 patients with a median follow-up of 90 months (range, 86-102 months). There were no adverse outcomes and satisfaction remained at 100% (6 patients, satisfied; 13 patients, very satisfied). No patient developed a recurrence of symptoms and signs of lateral elbow tendinopathy, and therefore no secondary intervention was required. The improvement from baseline and early term scores was sustained (P < .001 for all). At 90 months, there was a significant improvement in VAS scores and DASH–Compulsory scores compared with preprocedure scores and all follow-up times until 3 months. There was no difference in VAS scores and DASH–Compulsory scores at 90 months compared with 6 and 36 months. For DASH–Work scores, there was a significant improvement at 90 months compared with preprocedure scores, but there was no difference between DASH–Work scores at 90 months and scores at all other points of follow-up. At 90 months, hypervascularity remained resolved in 79% of patients, while all patients had reduced tendon swelling and sustained resolution or reduction of the hypoechoic lesion.

At the long-term follow-up of 90 months, ultrasonic percutaneous tenotomy of the brevis and the common extensor tendon, previously shown to enhance recovery of lateral elbow tendinopathy, demonstrated good durability of pain relief and functional recovery that was previously achieved. This was accompanied by sustained sonographic tissue healing with no significant deterioration.

The transplantation of mesenchymal stem cells (MSCs) into cartilage defects has led to variable cartilage repair outcomes. Previous in vitro studies have shown that ascorbic acid and reduced iron independently can improve the chondrogenic differentiation of MSCs. However, the combined effect of ascorbic acid and iron supplementation on MSC differentiation has not been investigated.

To investigate the combined in vivo effects of ascorbic acid and a US Food and Drug Administration (FDA)–approved iron supplement on MSC-mediated cartilage repair in mature Göttingen minipigs.

Controlled laboratory study.

We pretreated bone marrow–derived MSCs with ascorbic acid and the FDA-approved iron supplement ferumoxytol and then transplanted the MSCs into full-thickness cartilage defects in the distal femurs of Göttingen minipigs. Untreated cartilage defects served as negative controls. We evaluated the cartilage repair site with magnetic resonance imaging at 4 and 12 weeks after MSC implantation, followed by histological examination and immunofluorescence staining at 12 weeks.

Ascorbic acid plus iron–pretreated MSCs demonstrated a significantly better MOCART (magnetic resonance observation of cartilage repair tissue) score (73.8 ± 15.5), better macroscopic cartilage regeneration score according to the International Cartilage Repair Society (8.6 ± 2.0), better Pineda score (2.9 ± 0.8), and larger amount of collagen type II (28,469 ± 21,313) compared with untreated controls (41.3 ± 2.5, 1.8 ± 2.9, 12.8 ± 1.9, and 905 ± 1326, respectively). The obtained scores were also better than scores previously reported in the same animal model for MSC implants without ascorbic acid.

Pretreatment of MSCs with ascorbic acid and an FDA-approved iron supplement improved the chondrogenesis of MSCs and led to hyaline-like cartilage regeneration in the knee joints of minipigs.

Ascorbic acid and iron supplements are immediately clinically applicable. Thus, these results, in principle, could be translated into clinical applications.

Bone marrow stimulation (BMS) via microfracture historically has been a first-line treatment for articular cartilage lesions. However, BMS has become less favorable because of resulting fibrocartilage formation. Previous studies have shown that angiogenesis blockade promotes cartilage repair. Bevacizumab is a Food and Drug Administration–approved medication used clinically to prevent angiogenesis.

The intra-articular injection of bevacizumab would prevent angiogenesis after BMS and lead to improved cartilage repair with more hyaline-like cartilage.

Controlled laboratory study.

The dose of bevacizumab was first optimized in a rabbit osteochondral defect model with BMS. Then, 48 rabbits (n = 8/group/time point) were divided into 3 groups: osteochondral defect (defect), osteochondral defect + BMS (BMS group), and osteochondral defect + BMS + bevacizumab intra-articular injection (bevacizumab group). Rabbits were sacrificed at either 6 or 12 weeks after surgery. Three-dimensional (3D) micro–computed tomography (microCT), macroscope score, modified O’Driscoll histology scores, collagen type 2, Herovici staining, and hematoxylin and eosin staining were performed. Angiogenesis markers were also evaluated.

The intra-articular dose of 12.5 mg/0.5 mL bevacizumab was found to be effective without deleteriously affecting the subchondral bone. Intra-articular injection of bevacizumab resulted in significantly improved cartilage repair for the bevacizumab group compared with the BMS or the defect group based on 3D microCT, the macroscope score (both P < .05), the modified O’Driscoll histology score (P = .0034 and P = .019 vs defect and BMS groups, respectively), collagen type 2, Herovici staining, and hematoxylin and eosin staining at 6 weeks. Cartilage in the bevacizumab group had significantly more hyaline cartilage than did that in other groups. At 12 weeks, the cartilage layer regenerated in all groups; however, the bevacizumab group showed more hyaline-like morphology, as demonstrated by microCT, histology scores (P < .001 and .0225 vs defect and BMS groups, respectively), histology, and immunohistochemistry. The bevacizumab injection did not significantly change mRNA expressions of smooth muscle actin, vascular endothelial growth factor, or hypoxia-inducible factor-1 alpha.

Intra-articular injection of bevacizumab significantly enhanced the quality and quantity of hyaline-like cartilage after BMS in a rabbit model. Future large-animal and human studies are necessary to evaluate the clinical effect of this therapy, which may lead to improved BMS outcomes and thus the durability of the regenerated cartilage.

The use of bevacizumab may be an important clinical adjunct to improve BMS-mediated cartilage repair.

Long-term outcomes of current clinical interventions for osteochondral defect are less than satisfactory. One possible reason is an ignorance of the interface structure between cartilage and subchondral bone, the calcified cartilage zone (CCZ). However, the importance of natural CCZ in osteochondral defects has not been directly described.

To explore the feasibility of fabricating trilayer scaffold containing natural CCZ for osteochondral defects and the role of CCZ in the repair process.

Controlled laboratory study.

The scaffold was prepared by cross-linking lyophilized type II collagen sponge and acellular normal pig subchondral bone with or without natural CCZ. Autologous bone marrow stem cells (BMSCs) of minipig were mixed with type II collagen gel and injected into the cartilage layer of the scaffold before operation. Thirty minipigs were randomly divided into CCZ (n = 10), non-CCZ (n = 10), and blank control (n = 10) groups. An 8 mm–diameter full-thickness osteochondral defect was created on the trochlear surface, and scaffold containing BMSCs was transplanted into the defect according to grouping requirements. At 12 and 24 weeks postoperatively, specimens were assessed by macroscopic observation, magnetic resonance imaging examination, and histological observations (hematoxylin and eosin, Safranin O–fast green, type II collagen immunohistochemical, and Sirius red staining). Semiquantitative cartilage repair scoring was conducted using the MOCART (Magnetic Resonance Observation of Cartilage Repair Tissue) system and the O’Driscoll repaired cartilage value system.

The defects in the blank control and non-CCZ groups were filled with fibrous tissue, while the cartilage layer of the CCZ group was mainly repaired by hyaline cartilage at 24 weeks postoperatively. The superior repair outcome of the CCZ group was confirmed by MOCART and O’Driscoll score.

The trilayer scaffold containing natural CCZ obtained the best repair effect compared with the non-CCZ scaffold and the blank control, indicating the importance of the CCZ in osteochondral tissue engineering.

This study demonstrates the necessity to reconstruct CCZ in clinical osteochondral defect repair and provides a possible strategy for osteochondral tissue engineering.

Tendons heal by fibrotic repair, increasing the likelihood of reinjury. Animal tendon injury and overuse models have identified transforming growth factor beta (TGF-β) and bone morphogenetic proteins (BMPs) as growth factors actively involved in the development of fibrosis, by mediating extracellular matrix synthesis and cell differentiation.

To understand how TGF-β and BMPs contribute to fibrotic processes using tendon-derived cells isolated from healthy and diseased human tendons.

Controlled laboratory study.

Tendon-derived cells were isolated from patients with a chronic rotator cuff tendon tear (large to massive, diseased) and healthy hamstring tendons of patients undergoing anterior cruciate ligament repair. Isolated cells were incubated with TGF-β1 (10 ng/mL) or BMP-2 (100 ng/mL) for 3 days. Gene expression was measured by real-time quantitative polymerase chain reaction. Cell signaling pathway activation was determined by Western blotting.

TGF-β1 treatment induced ACAN mRNA expression in both cell types but less in the diseased compared with healthy cells (P < .05). BMP-2 treatment induced BGN mRNA expression in healthy but not diseased cells (P < .01). In the diseased cells, TGF-β1 treatment induced increased ACTA2 mRNA expression (P < .01) and increased small mothers against decapentaplegic (SMAD) signaling (P < .05) compared with those of healthy cells. Moreover, BMP-2 treatment induced ACTA2 mRNA expression in the diseased cells only (P < .05).

Diseased tendon–derived cells show reduced expression of the proteoglycans aggrecan and biglycan in response to TGF-β1 and BMP-2 treatments. These same treatments induced enhanced fibrotic differentiation and canonical SMAD cell signaling in diseased compared with healthy cells.

Findings from this study suggest that diseased tendon–derived cells respond differently than healthy cells in the presence of TGF-β1 and BMP-2. The altered responses of diseased cells may influence fibrotic repair processes during tendon healing.

Movement quality and neuromuscular balance are noted predictors of acute injury. Early sports specialization and extremely high activity levels have been linked to elevated risk of injury.

To investigate for any relationships among quality of physical movement, quantity of physical activity, and degree of sports specialization in a healthy cohort of active children and adolescents.

Cross-sectional study with prospectively collected data.

Healthy children between the ages of 10 and 18 years were recruited and completed the Hospital for Special Surgery Pediatric Functional Activity Brief Scale to assess quantity of physical activity and the Jayanthi scale to assess degree of sports specialization (high, score of 2 or 3; low, score of 0 or 1). Movement quality was assessed using motion analysis sensors during 5 repetitions of 4 different jumping and squatting motions, with a maximum score of 100 per participant. Independent-samples t tests were used to compare participants with high versus low specialization on physical activity and movement quality. A Spearman correlation was used to determine the relationship between quantity of physical activity and movement quality, and linear regression was used to assess for the effect of participant age on relevant covariables.

Final analyses included 147 participants (72% male) with a mean ± SD age of 13.4 ± 2.2 years. Participants who were highly specialized displayed better movement quality than did participants with low sports specialization (27.6 ± 14.0 vs 19.8 ± 10.1; P < .01). Participants who were highly specialized had significantly higher activity levels (24.6 ± 5.9 vs 18.1 ± 6.9; P < .001). Movement quality was moderately correlated with physical activity level (r = 0.335; P < .001). Physical activity; hours of organized sports activity; hours of free, unorganized physical activity; and specialization level were not significant predictors of movement quality when controlling for age. Age alone predicted 24.2% of the variance in the overall movement quality score (R² = 0.242; B = 3.0; P < .001).

This study found that sports specialization and physical activity levels were not associated with movement quality when controlling for age, which was the most important variable predicting athletic movement quality. Although all participants displayed movement patterns that were associated with high risk for injury, overall movement quality improved with advancing chronological age.

All young athletes should ensure that neuromuscular training accompanies sport-specific training to reduce risk of injury.

Aerobic exercise has emerged as a useful treatment to improve outcomes among individuals who experience a concussion. However, compliance with exercise recommendations and the effect of exercise volume on symptom recovery require further investigation.

To examine (1) if an 8-week aerobic exercise prescription, provided within 2 weeks of concussion, affects symptom severity or exercise volume; (2) whether prescription adherence, rather than randomized group assignment, reflects the actual effect of aerobic exercise in postconcussion recovery; and (3) the optimal volume of exercise associated with symptom resolution after 1 month of study.

Cohort study; Level of evidence, 2.

Individuals randomized to an exercise intervention (n = 17; mean age, 17.2 ± 2.0 years; 41% female; initially tested a mean of 11.3 ± 2.8 days after injury) or standard of care (n = 20; mean age, 16.8 ± 2.2 years; 50% female; initially tested a mean of 10.7 ± 3.2 days after injury) completed an aerobic exercise test within 14 days of injury. They returned for assessments 1 month and 2 months after the initial visit. The aerobic exercise group was instructed to exercise 5 d/wk, 20 min/d (100 min/wk), at a target heart rate based on an exercise test at the initial visit. Participants reported their exercise volume each week over the 8-week study period and reported symptoms at each study visit (initial, 1 month, 2 months). Because of low compliance in both groups, there was no difference in the volume of exercise between the 2 groups.

There were no significant symptom severity differences between the intervention and standard-of-care groups at the initial (median Post-Concussion Symptom Inventory, 15 [interquartile range = 10, 42] vs 20 [11, 35.5]; P = .26), 1-month (4 [0, 28] vs 5.5 [0.5, 21.5]; P = .96), or 2-month (6.5 [0, 27.5] vs 0 [0, 4]; P = .11) study visits. Exercise volume was similar between groups (median, 115 [54, 225] vs 88 [28, 230] min/wk for exercise intervention vs standard of care; P = .52). Regardless of group, those who exercised <100 min/wk reported significantly higher symptom severity at the 1-month evaluation compared with those who exercised ≥100 min/wk (median, 1.5 [0, 7.5] vs 12 [4, 28]; P = .03). Exercising ≥160 min/wk successfully discriminated between those with and those without symptoms 1 month after study commencement (classification accuracy, 81%; sensitivity, 90%; specificity, 78%).

Greater exercise volume was associated with lower symptom burden after 1 month of study, and an exercise volume >160 min/wk in the first month of the study was the threshold associated with symptom resolution after the first month of the study. Because our observation on the association between exercise volume and symptom level is a retrospective and secondary outcome, it is possible that participants who were feeling better were more likely to exercise more, rather than the exercise itself driving the reduction in symptom severity.

Concussions are a source of major concern in rugby, and a limited number of studies have attempted to identify risk factors for these injuries.

To investigate the incidence of match concussion and associated risk factors, including individual workload, anthropometric variables, playing position, and season phase, in elite rugby union players.

Case-control study; Level of evidence 3.

All concussions and explanatory variables were collected for every match over 5 consecutive seasons (2014-2018) in 1334 professional players participating in the French Top 14 championship. Concussion risk was estimated using mixed effects Poisson regression.

Mean match concussion incidence equated to 10.4 (95% CI, 9.3-11.5) concussions for 1000 hours of game exposure. A peak was reached in the 2016-2017 season (13.7; 95% CI, 11.0-16.5). A greater risk was observed in the playoffs as compared with the first phase of the season (incidence rate ratio, 3.96; 95% CI, 2.10-7.35). In comparison with other positions, half-backs incurred the highest rate of concussion events (incidence, 16.1; 95% CI, 11.8-20.3). Irrespective of playing position, those with greater height and lower body mass reported a higher risk of concussions (P = .02), especially during tackling actions for lighter players (P = .01) and during other match events for taller players (P = .03). When adjusted for season phase, players who had accumulated a higher amount of playing time since the beginning of the season demonstrated a lower risk of concussion (P = .005).

Inter- and intraseasonal variations in concussion rates were observed. Within positional groups, lighter and taller players were more at risk, with the highest incidence generally observed in half-backs. Workload was measured by the number of matches played before a concussion event, and it appeared to have a protective rather than deleterious effect on concussion risk.

The sex of an athlete is thought to modulate concussion incidence; however, the effects of sex on concussion severity and recovery are less clear.

To evaluate sex differences in concussion severity and recovery using a large, heterogeneous sample of young student-athletes with the goal of understanding how sex affects concussion outcomes in young athletes.

Cohort study; Level of evidence, 3.

The Immediate Post-Concussion Assessment and Cognitive Testing results of 11,563 baseline and 5216 postinjury tests were used to calculate the incidence of concussion of adolescent male and female student-athletes ages 12 to 22 years (median, 15 years). The postinjury tests of 3465 male and 1751 female student-athletes evaluated for concussion or head trauma were used to assess differences in the Severity Index (SI) and recovery. Chi-square tests and t tests were used to compare differences in demographic characteristics, incidence, and SI between the 2 cohorts. Multivariable linear, logistic, and Cox proportional hazards regressions were used to control for differences between cohorts in analyses of incidence, SI, and recovery.

When we controlled for demographic differences, female participants had higher odds of concussion (odds ratio, 1.62; 95% CI, 1.40-1.86; P < .0001) and higher SI after concussion (β = 0.67; 95% CI, 0.02-1.32; P = .04). This discrepancy in SI was a result of differences in Symptom (2.40 vs 2.94; P < .0001) and Processing Speed (0.91 vs 1.06; P = .01) composite scores between male and female participants, respectively. We found no effect of sex on time to recovery when controlling for initial concussion SI (hazard ratio, 0.94; 95% CI, 0.78-1.12; P = .48).

Using large, multisport cohorts, this study provides evidence that female athletes are at higher risk for more concussions and these concussions are more severe, but male and female athletes have similar recovery times when the analysis controls for initial concussion SI.

Blood flow restriction (BFR) is a novel technique involving the use of a cuff/tourniquet system positioned around the proximal end of an extremity to maintain arterial flow while restricting venous return.

To analyze the available literature regarding the use of BFR to supplement traditional resistance training in healthy athletes.

Systematic review.

A systematic review was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. From November to December 2018, studies that examined the effects of BFR training in athletes were identified using PubMed and OVID Medline. Reference lists from selected articles were analyzed for additional studies. The inclusion criteria for full article review were randomized studies with control groups that implemented BFR training into athletes’ resistance training workouts. Case reports and review studies were excluded. The following data were extracted: patient demographics, study design, training protocol, occlusive cuff location/pressure, maximum strength improvements, muscle size measurements, markers of sports performance (eg, sprint time, agility tests, and jump measurements), and other study-specific markers (eg, electromyography, muscular torque, and muscular endurance).

The initial search identified 237 articles. After removal of duplicates and screening of titles, abstracts, and full articles, 10 studies were identified that met the inclusion criteria. Seven of 9 (78%) studies found a significant increase in strength associated with use of BFR training as compared with control; 4 of 8 (50%) noted significant increases in muscle size associated with BFR training; and 3 of 4 (75%) reported significant improvements in sport-specific measurements in the groups that used BFR training. Occlusive cuff pressure varied across studies, from 110 to 240 mm HG.

The literature appears to support that BFR can lead to improvements in strength, muscle size, and markers of sports performance in healthy athletes. Combining traditional resistance training with BFR may allow athletes to maximize athletic performance and remain in good health. Additional studies should be conducted to find an optimal occlusive pressure to maximize training improvements.

CRD42019118025 (PROSPERO).

Little consensus is available regarding the standard treatment for recurrent anterior instability of the shoulder. Typically, treatment selection has been based on training and tradition rather than the available evidence.

This study aimed to compare the clinical outcomes between arthroscopic Bankart procedure and the Latarjet procedure in the treatment of recurrent anterior shoulder instability with emphasis on follow-up time.

Systematic review and meta-analysis.

We searched PubMed, Cochrane Central Register of Controlled Trials, Scopus, Ovid, and Web of Science up to January 2018 and included studies that compared arthroscopic Bankart versus Latarjet for treatment of anterior shoulder instability. Continuous data, such as operative time and patient-reported outcomes, were pooled as mean differences (MDs), whereas dichotomous data, such as recurrence, revision, redislocation, arthropathy, infection, and hematoma, were pooled as risk ratios (RRs), with 95% CIs.

Pooling data from 7 cohort studies (3275 patients) showed that arthroscopic Bankart was associated with a higher risk of redislocation (RR, 2.74; 95% CI, 1.48-5.06; P = .03), a higher risk of recurrence (RR, 2.87; 95% CI, 1.91-4.30; P < .0001), and a lower risk of infection (RR, 0.16; 95% CI, 0.06-0.43; P = .0002) compared with Latarjet, while the effect size did not favor arthroscopic Bankart or Latarjet in terms of Rowe score (MD, 0.22; 95% CI, –5.64 to 6.08; P = .94), revision (RR, 0.34; 95% CI, 0.08-1.39; P = .13), and hematoma (RR, 0.20; 95% CI, 0.03-1.19; P = .07). The effect estimate showed a pronounced advantage for Latarjet from 6 to 10 years postoperatively in terms of recurrence and redislocation (RR, 3.00; 95% CI, 1.98-4.56 and RR, 2.85; 95% CI, 1.51-5.38, respectively).

Our results showed that Latarjet had less risk of recurrence and redislocation with longer follow-up time. Both procedures were comparable in terms of Rowe score, the need for revision, and postoperative hematoma formation, whereas Bankart repair was associated with a lower risk of infection.

Birth tissue products from amnion, chorion, umbilical cord, amniotic fluid, or cord blood are frequently marketed as viable sources of stem cells and growth factors. It can be difficult for health care professionals to differentiate implied from explicit conclusions in reported product analyses.

To provide an educational platform for health care professionals to interpret data presented in the promotion of birth tissue products.

Descriptive laboratory study and expert opinion; Level of evidence, 5.

A cord blood product was analyzed by 3 methods for cell viability, 2 methods for assessment of cell morphology and cell type, multicolor flow cytometry to identify stem cells, and enzyme-linked immunosorbent assay (ELISA) plus Western blot for analysis of interleukin 1 receptor antagonist protein (IL-1ra). These data were compared with analyses reported by the manufacturer.

Cell viability in the cord blood product was less than reported by the manufacturer, the cells were primarily leukocytes, no stem cells were present, and the concentration of IL-1ra was falsely increased due to nonspecific antibody binding in the sample.

To assess birth tissue products, health care professionals should consider the following: (1) Understanding fluorescent dyes is important for assessing cell viability data—green does not always mean alive. (2) The report of “cells” in the product does not necessarily mean “stem cells”; microscopic images of at least ×20 or a hemogram should be evaluated to determine cell type (leukocyte, red blood cells, etc). (3) There is no single cluster of differentiation (CD) marker on flow cytometry to identify stem cells. (4) Biological tissues are complex substances, and inaccurately increased measurements of growth factors could be present in ELISA results because most ELISAs are not designed or validated for use in biologics. Furthermore, the reported measurement of growth factors should be considered relative to concentrations in native biological tissues and plasma.

Health care professionals should be able to interpret cell viability, cell morphology, stem cell analysis using CD markers, and growth factor analysis when considering use of a birth tissue product in patients.

The incidence of anterior cruciate ligament (ACL) injuries among adolescent athletes is steadily increasing. Identification of the highest risk sports for ACL injuries by sex and competitive setting (ie, practice vs match) is important for targeting injury prevention programs.

To identify the risk of ACL injuries in adolescent athletes by sport, sex, and setting across a variety of common US and international sports.

Meta-analysis.

Essentially, 3 online databases (PubMed, Embase, and Cochrane Library) were searched for all studies of ACL injuries per athlete-exposure (AE) or hours of exposure in adolescent athletes. Injuries were then pooled and incidence rates (IRs) reported per 1000 AEs or hours of exposure, with the relative risk (RR) of injuries calculated for sex-comparable sports. IRs per competitive setting (match vs practice) were also calculated.

A total of 1235 ACL injuries over 17,824,251 AEs were identified (IR, 0.069 [95% CI, 0.065-0.074]), with 586 of these injuries in girls across 6,986,683 AEs (IR, 0.084 [95% CI, 0.077-0.091]) versus 649 injuries in boys over 10,837,568 AEs (IR, 0.060 [95% CI, 0.055-0.065]). Girls had a higher overall rate of ACL injuries (RR, 1.40 [95% CI, 1.25-1.57]), with the most disproportionate risk observed in basketball (RR, 4.14 [95% CI, 2.98-5.76]). The risk of ACL injuries by sex was highest in girls’ soccer (IR, 0.166 [95% CI, 0.146-0.189]) and boys’ football (IR, 0.101 [95% CI, 0.092-0.111]). ACL injuries were over 8 (RR, 8.54 [95% CI, 6.46-11.30]) and 6 (RR, 6.85 [95% CI, 5.52-8.49]) times more likely to occur in a match versus a practice setting for female and male athletes, respectively.

The risk of ACL injuries overall approached nearly 1 per 10,000 AEs for female athletes, who were almost 1.5 times as likely as male athletes to suffer an ACL injury across all adolescent sports. A multisport female athlete was estimated to have a nearly 10% risk of ACL injuries over her entire high school or secondary school career. Specifically, male and female adolescents playing soccer, basketball, lacrosse, and football appeared at particular risk of injuries, a finding that can be used to target an injury intervention.