The American Journal of Sports Medicine

Few studies have investigated the outcome ≥20 years after an anterior cruciate ligament reconstruction (ACLR) with a bone–patellar tendon–bone autograft, and there is a wide range in the reported rates of radiographic osteoarthritis (OA).

To report on radiographic OA development and to assess risk factors of knee OA at a median 25 years after ACLR with a bone–patellar tendon–bone autograft.

Case-control study; Level of evidence, 3.

Unilateral ACLRs performed at a single center from 1987 to 1994 were included (N = 235). The study population was followed prospectively with clinical testing and questionnaires. Results from the 3-month, 12-month, and median 25-year follow-up are presented. In addition, a radiographic evaluation was performed at the final follow-up. Radiographic OA was defined as Kellgren-Lawrence grade ≥2 or having undergone ipsilateral knee replacement surgery. Possible predictors of OA development included patient age, sex, time from injury to surgery, use of a Kennedy ligament augmentation device, any concomitant meniscal surgery, and return to preinjury sports after surgery.

At long-term follow-up, 60% (141/235) of patients had radiographic OA in the involved knee and 18% (40/227) in the contralateral knee (P < .001). Increased age at surgery, male sex, increased time between injury and surgery, a Kennedy ligament augmentation device, and medial and lateral meniscal surgery were significant predictors of OA development in univariate analyses. Return to preinjury level of sports after surgery was associated with less development of OA. In the multivariate model, medial meniscal surgery and lateral meniscal surgery were independently associated with OA development. The adjusted odds ratio was 1.88 (95% CI, 1.03-3.43; P = .041) for medial meniscal surgery and 1.96 (95% CI, 1.05-3.67; P = .035) for lateral meniscal surgery. Patients who had developed radiographic signs of OA had significantly lower Knee injury and Osteoarthritis Outcome Score and Lysholm scores at long-term follow-up.

At 25 years after ACLR, 60% of patients had developed OA in the involved knee, and these patients reported significantly lower subjective outcomes. Medial meniscal surgery and lateral meniscal surgery were independent predictors of OA development at long-term follow-up.

The optimal orientation of the anterolateral extra-articular reconstruction (ALLR) femoral tunnel to avoid collision with the anterior cruciate ligament reconstruction (ACLR) femoral tunnel is not clearly defined in the literature.

To define the optimal combination of orientations of the ALLR femoral tunnel and the ACLR femoral tunnel using an inside-out technique to minimize risk of collision between these tunnels.

Descriptive laboratory study.

Three-dimensional reconstruction of magnetic resonance imaging scans of 40 knees after an isolated ACLR with an inside-out femoral technique was used to assess the collision risk between ACLR and virtual ALLR tunnels. The optimal ACLR tunnel orientation was defined as having the safest distance from the ALLR tunnel. A second collision analysis was performed on all patients presenting with an optimal orientation of the ACLR tunnel to then define the optimal ALLR tunnel orientation. The potential for trochlear damage was also studied. A collision risk of 0% to 5% was considered acceptable and referred to as “low risk.”

The only ALLR tunnel orientation presenting a low risk of collision with the ACLR tunnel was with an axial angle of 40° anteriorly and a coronal angle of 0°. This orientation presented a 48% risk of trochlear damage with the guide wire of the ALLR tunnel. The more posterior the orientation of the ACLR, the larger the distance from the ALLR tunnel. Among the 22 patients presenting with an optimal ACLR tunnel (alpha angle superior to 40°), the ALLR tunnels aimed with 1 of these 3 orientations presented a low risk of tunnel collision and trochlear damage: 40° axial and 10° coronal, 35° axial and 5° coronal, or 30° axial and 0° coronal.

To minimize risk of tunnel collision or trochlear damage when combining an inside-out ACLR with an ALLR, the ACLR tunnel should be performed with a posterior orientation (alpha angle >40°), and the ALLR tunnel should be aimed with 1 of 3 orientations: 40° axial and 10° coronal, 35° axial and 5° coronal, or 30° axial and 0° coronal.

Contextualizing patient-reported outcomes (PROs) by defining clinically relevant differences is important. Considering that anterior cruciate ligament reconstruction (ACLR) ideally results in the restoration of normal knee function, an assessment of patients’ perception of being “completely better” (CB) may be of particular value.

The purpose of this study was to assess the prevalence and characteristics of patients who self-report a CB status after ACLR. Additionally, we aimed to determine whether PROs were associated with a CB status after ACLR as well as to determine CB status thresholds for 2-year and change in values.

Case-control study; Level of evidence, 3.

We retrospectively analyzed data from an orthopaedic registry at a single institution. Patients were administered the Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (PF), PROMIS Pain Interference (PI), and International Knee Documentation Committee (IKDC) Subjective Knee Form preoperatively and at 2 years after ACLR. Additionally, patients completed a CB anchor question at 2 years after ACLR. Thresholds for 2-year and change in PRO scores associated with achieving a CB status were identified with 90% specificity.

Overall, 95 of the 136 patients (69.9%) considered their condition to be CB at 2 years after surgery. The 2-year and change in PROMIS PF, PROMIS PI, and IKDC scores were significantly better in the CB group than in the non-CB group. Thresholds associated with a CB status for 2-year PROMIS PF, PROMIS PI, and IKDC scores were more reliable than those for changes in scores and were ≥63, ≤44, and ≥80, respectively. Thresholds for the change in PROMIS PF, PROMIS PI, and IKDC scores were ≥19, ≤–16, and ≥44, respectively.

The majority of patients reported that they were CB at 2 years after ACLR. This study may serve as a reference for orthopaedic surgeons and researchers when considering outcomes after ACLR.

There are limited epidemiologic data examining the incidence of pediatric anterior cruciate ligament reconstruction (ACLR) over the past decade.

To examine statewide population trends in the incidence of ACLR in a pediatric population.

Descriptive epidemiology study.

Inpatient and outpatient claims for pediatric patients who underwent ACLR between 2009 and 2017 were identified in the New York Statewide Planning and Research Cooperative System database via International Classification of Diseases (ICD), Revision 9, Clinical Modification; ICD, Revision 10, Clinical Modification and Procedural Classification System; or Current Procedural Terminology codes. New York population data for each year between 2009 and 2017 were used from the New York State Department of Health to calculate the rates of ACLR per 100,000 people aged 3 to 19 years and determine the 95% confidence limits. The rates were then stratified by age, sex, and insurance. Two-year rates of revision and contralateral ACLR were also analyzed by sex.

Between 2009 and 2017, 20,170 pediatric ACLRs were identified. The rates of pediatric ACLR increased steadily from 49.3 per 100,000 in 2009 (95% CI, 47.2-51.4) to a peak of 61.0 (95% CI, 58.6-63.4) in 2014 and decreased to 51.8 (95% CI, 49.6-54.1) by 2017. The age group 15 to 17 years had the highest rates of ACLR of all age groups, peaking at 198.5 (95% CI, 188.3-208.7) per 100,000. Analysis by sex showed that ACLR rates between males and females were not different. Males had a 2-year ipsilateral revision rate of 4.3%, while females had a rate of 3.3% (P = .0001). Females had a contralateral ACLR rate of 4.0%, while males had a rate of 2.6% (P = .0002).

Pediatric ACLR rates continued to rise until 2014, but there was a demonstrable decrease in rates after 2014. This decline in pediatric ACLR may point to the efficacy of injury prevention programs or changes in practice management. The high revision rate in males and high contralateral surgery rate in females can help guide patient counseling for return to play and complication risk.

This study showed that ACLR in pediatric patients may be decreasing in recent years. There were differences in revision and contralateral ACLR by sex.

An intra-articular infection after anterior cruciate ligament (ACL) reconstruction (ACLR) is a rare complication but one with potentially devastating consequences. The rare nature of this complication raises difficulties in detecting risk factors associated with it and with worse outcomes after one has occurred.

To (1) evaluate the association between an infection after ACLR and potential risk factors in a large single-center cohort of patients who had undergone ACLR and (2) assess the factors associated with ACL graft retention versus removal.

Case-control study; Level of evidence, 3.

All ACLR procedures performed at our institution between January 2010 and December 2018 were reviewed; a total of 11,451 procedures were identified. A retrospective medical record review was performed to determine the incidence of infections, patient and procedure characteristics associated with an infection, infection characteristics, incidence of ACL graft retention, and factors associated with the retention versus removal of an ACL graft. Multivariable logistic regression analysis was used to identify potential risk factors for an infection after ACLR.

Of the 11,451 ACLR procedures, 48 infections were identified (0.42%). Multivariable logistic regression analysis revealed revision ACLR (odds ratio [OR], 3.13 [95% CI, 1.55-6.32]; P = .001) and younger age (OR, 1.06 [95% CI, 1.02-1.10]; P = .001) as risk factors for an infection. Compared with bone–patellar tendon–bone autografts, both hamstring tendon autografts (OR, 4.39 [95% CI, 2.15-8.96]; P < .001) and allografts (OR, 5.27 [95% CI, 1.81-15.35]; P = .002) were independently associated with an increased risk of infections. Overall, 15 ACL grafts were removed (31.3%). No statistically significant differences besides the number of irrigation and debridement procedures were found for retained versus removed grafts, although some trends were identified (P = .054).

In a large single-center cohort of patients who had undergone ACLR and those with an infection after ACLR, patients with revision cases and younger patients were found to have a higher incidence of infection. The use of bone–patellar tendon–bone autografts was found to be associated with the lowest risk of infection after ACLR compared with both hamstring tendon autografts and allografts. Larger cohorts with a larger number of infection cases are needed to determine the factors associated with graft retention versus removal.

Although the risk of tibial tunnel convergence in the setting of multiligamentous reconstruction has been reported in the literature, the risk of tunnel convergence in the setting of posterior cruciate ligament (PCL), anterior cruciate ligament (ACL) reconstruction and medial and lateral meniscus root repair has not been defined.

To examine the risk of tunnel convergence and to determine optimal tunnel placement for ACL and PCL reconstruction performed in conjunction with posterior medial and lateral meniscus root repairs on the anteromedial proximal tibia.

Descriptive laboratory study.

Three-dimensional (3D) tibial models were created using computed tomography scans of 20 cadaveric specimens. After determining optimal tunnel entry and exit points for ACL and PCL reconstructions, and medial and lateral meniscus root reattachment to the anatomic footprints, we used image processing software to create root tunnels over the anteromedial tibia on the tibial models. ACL and PCL tunnels were kept constant. The meniscus root repair tunnels were then reoriented to match the angle of the ACL tunnel, making both tunnels parallel in the sagittal plane. Tunnel convergence risk was analyzed by identifying the shortest 3D distance between tunnel axes and subtracting the radius of each tunnel from this distance for single- and double-tunnel repair techniques in both case scenarios.

All specimens demonstrated convergence between the ACL and lateral meniscus root tunnels when the root tunnel’s entry was created proximal to the ACL tunnel’s entry for single- and double-tunnel techniques, but no convergence was seen between these tunnels using the parallel orientation in the sagittal plane. There were no cases of convergence between the ACL and medial meniscus root tunnels in any of the configurations. The greatest distance between the ACL and medial meniscus root tunnels was achieved using the single-tunnel technique in parallel orientation (12.1 ± 2.8 mm). There were no cases of convergence between the PCL and medial meniscus root tunnels in the original orientation; however, 2 of 20 specimens demonstrated convergence using the parallel orientation with the double-tunnel technique, and there were no cases of convergence using the single-tunnel technique. The PCL and lateral meniscus root tunnels did not demonstrate convergence in any configuration.

There was a high risk of convergence between ACL and posterior meniscus root tunnels when all the tunnels were created on the anteromedial tibia. Reorienting meniscus root tunnels parallel to ACL tunnels may help reduce this risk. There is increased risk of tunnel convergence with root repairs in cases of bicruciate reconstructions, and therefore a double-tunnel root repair technique should be used with caution.

To avoid tibial tunnel convergence when performing ACL and PCL reconstruction with medial and lateral meniscus root repair, surgeons should reorient the meniscus root repair tunnels to be parallel on the sagittal plane to the ACL tunnel to decrease the risk of convergence. In cases of bicruciate ligament reconstruction, use of the double-tunnel technique requires caution to avoid convergence risk with the PCL tunnel.

The discoid lateral meniscus (DLM) is one of the most common congenital anomalies of the knee. The pathomorphology of DLM varies. Current classification systems are inadequate to describe the spectrum of abnormality.

A study group of pediatric orthopaedic surgeons from 20 academic North American institutions developed and tested the reliability of a new DLM classification system.

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

After reviewing existing classifications, we developed a comprehensive DLM classification system. Four DLM features were evaluated: meniscal width, meniscal height, peripheral stability, and meniscal tear. Stepwise arthroscopic examination using anteromedial and anterolateral viewing portals was established for evaluating these features. Three senior authors who were not observers selected 50 of 119 submitted videos with the best clarity and stepwise examination for reading. Five observers performed assessments using the new classification system to assess interobserver reliability, and a second reading was performed by 3 of the 5 observers to assess intraobserver reliability using the Fleiss κ coefficient (fair, 0.21-0.40; moderate, 0.41-0.60; substantial, 0.61-0.80; excellent, 0.81-1.00).

Interobserver reliability was substantial for most rating factors: meniscal width, meniscal height, peripheral stability, tear presence, and tear type. Interobserver reliability was moderate for tear location. Intraobserver reliability was substantial for meniscal width and meniscal height and excellent for peripheral stability. Intraobserver agreement was moderate for tear presence, type, and location.

This new arthroscopic DLM classification system demonstrated moderate to substantial agreement in most diagnostic categories analyzed.

The effect of coronal plane alignment on the outcomes of repairs of the medial meniscus root remains unclear.

Increased preoperative varus alignment is associated with higher failure rates and lower patient-reported outcomes (PROs) after isolated repair of the medial meniscus root.

Case series; Level of evidence, 4.

Patients aged 18 years or older who underwent arthroscopy-assisted repair of the medial posterior meniscus root over a 7-year period were included. The mechanical axis of the knee was measured preoperatively. Osteoarthritis was assessed radiographically preoperatively and at the final follow-up according to the Kellgren-Lawrence grading scale. Failure was defined as any patient having to undergo revision root repair, partial meniscectomy of the previously repaired meniscus, debridement, lysis of adhesions, or conversion to arthroplasty.

A total of 53 patients (29 women, 24 men) with a mean age of 51.3 years were included in the follow-up analysis. The mean time of follow-up after surgery was 3.3 years (range, 22-77 months). Significant improvements were observed in all PROs analyzed. Decreased varus as measured by alignment percentage was correlated with baseline Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain (P = .023) and WOMAC Stiffness (P = .022). Alignment percentage was also significantly negatively correlated with postoperative WOMAC Stiffness (P = .005) and positively correlated with Lysholm (P = .003) and International Knee Documentation Committee (P = .009) scores. Higher baseline Kellgren-Lawrence grade was correlated with worse postoperative PROs (P < .05), except 12-Item Short Form Health Survey Mental Component Summary and satisfaction. Eight patients who underwent a concomitant high tibial osteotomy (HTO) achieved lower PROs in all scales analyzed, regardless of their alignment. When excluding patients who underwent HTO, postoperative Lysholm score (P = .004) and postoperative WOMAC Stiffness (p = 0.014) were inferior among the patients with >5° of varus.

Lower extremity alignment closest to neutral correlated with improved PROs. Patients who underwent a concurrent HTO had worse PROs than those who did not undergo HTO.

The intra-articular immune response after ligamentous, meniscal, or focal chondral knee injuries likely plays a role in intra-articular healing and the onset and progression of posttraumatic osteoarthritis.

To evaluate the association of synovial fluid cytokine concentrations measured at the time of knee arthroscopy with intermediate-term functional outcomes after knee arthroscopy based on the Lysholm score.

Cohort study; Level of evidence, 2.

This was a prospective cohort study of patients undergoing arthroscopic knee surgery. Synovial fluid was aspirated from the injured knee immediately before surgical incision, and the concentrations of 10 cytokines were analyzed using immunoassay. Principal component regression was used to create a model to predict patient-reported Lysholm score at a minimum of 5 years postoperatively. Hierarchical clustering was performed to identify groups of patients with similar synovial fluid inflammatory phenotypes. Lysholm scores and cytokine concentrations were compared between clusters.

A total of 26 patients (mean age, 40.33 ± 16.40 years) were included in the analysis. The mean duration between surgery and follow-up was 6.69 ± 0.72 years. A model consisting of 2 principal components (PC1, PC2) explained 62.48% of the variance in the cytokine data and 52.03% of the variance in intermediate-term Lysholm score. Hierarchical clustering resulted in 3 patient clusters based on the principal components used in the regression model. Despite no baseline differences in Lysholm score, cluster 3 demonstrated significantly greater intermediate-term Lysholm score compared with cluster 2 (94.33 vs 76.09, respectively; 95% CI, 5.96-30.52; P = .006) and cluster 1 (94.33 vs 52.33, respectively; 95% CI, 24.09-59.91; P = .003). Cluster 3, when compared with the overall means, was characterized by greater PC1 value (1.01 vs 0.00, respectively; P = .030) and greater PC2 value (0.86 vs 0.00, respectively; P = .002).

The concentrations of select synovial fluid cytokines assessed at the time of knee arthroscopy can be used to explain more than half of the variance in intermediate-term functional outcomes.

Precise osteochondroplasty is important in arthroscopic hip surgery for cam-type femoroacetabular impingement (FAI). Although computer-assisted surgery with a navigation system may enhance the accuracy of arthroscopic osteochondroplasty, few clinical studies have assessed its accuracy.

To evaluate the accuracy of arthroscopic osteochondroplasty by a computed tomography (CT)–based navigation system for cam-type FAI, using 3-dimensional (3D) reconstruction with more detail compared with previous methods.

Case series; Level of evidence, 4.

Twenty patients (14 men and 6 women) who underwent navigation-assisted arthroscopic surgery for cam-type FAI were included. The preoperative 3D model of the femur was constructed from each patient’s CT data, and a planned model with virtual cam resection was generated. A femoral model was reconstructed from CT data postoperatively. The 3 models for each patient were overlaid using a 3D model registration method. Then, the contours of the bone resection area of each model were compared by measuring them. To measure the deviation between planned and actual bone resections, 4 cross-sectional images of the 3 femoral models were set at one-quarter intervals from the femoral head radius. All measurements were based on clockface lines set around the femoral neck axis at 30-minute intervals. Differences between the planned and postoperative contour lines were deemed resection deviations.

All cam resections were performed in the anterior half of the region of interest. Therefore, only the anterior half (48 points) of the 96 points per case were analyzed. In 876 (91.3%) points of the total measurement points (960 points/20 cases), the error in resection depth was within 3 mm. Overresection was observed at 35 (3.6%) points and underresection at 49 (5.1%) points. The observed maximum deviations from the planned models were 6.3 mm overresection and –7.1 mm underresection. The alpha angles of the postoperative model at the posterior 9- to 3-o’clock position were <55° in all patients.

Navigation-assisted arthroscopic osteochondroplasty showed favorable accuracy. Underresection was more frequent than overresection on the anterosuperior side of the femur, despite assistance of the navigation system.

The workers’ compensation (WC) status has been associated with inferior outcomes in orthopaedic procedures and is usually excluded from clinical outcome studies. Therefore, comparative studies based on WC status are scarce.

(1) To determine outcomes of patients with WC claims treated with hip arthroscopy for labral tears at a minimum 5-year follow-up and (2) to compare these findings with a propensity score–matched control group without WC claims.

Cohort study; Level of evidence, 3.

Patients were propensity score matched to a control group without WC claims. Data were prospectively collected for all patients undergoing hip arthroscopy. Patients were included if they received primary hip arthroscopy for labral tears in the setting of femoroacetabular impingement, had a WC claim, and had preoperative and minimum 5-year follow-up patient-reported outcomes ([PROs]; modified Harris Hip Score [mHHS], Non-Arthritic Hip Score [NAHS], Hip Outcome Score–Sports Specific Subscale [HOS-SSS], and visual analog scale [VAS] for pain). Clinical outcomes were measured using the Patient Acceptable Symptom State (PASS), minimal clinically important difference (MCID), and maximum outcome improvement satisfaction threshold (MOI).

A total of 111 from 132 (84.1%) eligible WC patients met the inclusion criteria with an average follow-up time of 80.3 ± 37.3 months. WC cases demonstrated significant improvement from preoperatively to a minimum 5-year follow-up for mHHS, NAHS, HOS-SSS, and VAS for pain (P < .05). WC patients returned to work at a 66% rate, with an average clearance time of 4.7 months to light duty and 9.5 months to heavy duty. When compared with the control group, the WC group demonstrated lower pre- and postoperative PROs (P < .05); however, WC cases had a greater magnitude of improvement (ΔmHHS [P = .0012], ΔNAHS [P < .001], and ΔHOS-SSS [P = .012]). Rates of achieving MCID and MOI were similar in both groups (P > .05). The WC group went on to receive a future arthroscopy in 19 cases (17.1%), while 10 cases (4.5%) in the control group required revision arthroscopy (P < .001). Patients in both the WC and the control groups converted to total hip arthroplasty at similar rates (13.3% and 15.4%, respectively; P > .05).

Patients with WC claims treated with hip arthroscopic surgery showed significant improvement and high rates of returning to work at a minimum 5-year follow-up. Although having lower scores in PROs and achieving PASS rates, no differences were found in MCID and MOI rates. Furthermore, WC patients had a greater magnitude of improvement from preoperatively to a minimum 5-year follow-up after hip arthroscopy. Therefore, even though more studies are needed to determine the causes of inconsistent outcomes in the WC population, hip arthroscopy can effectively treat labral tears in the setting of femoroacetabular impingement, regardless of the WC status.

Labral reconstruction has been described as a treatment option for irreparable labral tear. Labral graft size ranges from 5 to 7 mm² for reconstruction. A thicker labral graft could support mechanical stability and protect cartilage better. No study has compared the effect of graft thickness on clinical outcomes.

The purpose of this study was to compare patient-reported outcomes between hips reconstructed with an autologous iliotibial band (AUITB; 5 mm²) graft and with an allogenic tibialis anterior (ALTA; 7 mm²) tendon graft. Our hypothesis was that hips reconstructed with a thicker allograft (7 mm²) would have better clinical outcomes than those with a smaller autograft (5 mm²).

Cohort study; Level of evidence, 2.

A total of 42 patients (aged 21 to 54 years) underwent arthroscopic hip segmental labral reconstruction during the study period of January 2016 to November 2018. Twenty patients had reconstruction with AUITB grafts (5 mm²) and 22 with ALTA grafts (7 mm²). Both groups had minimum 2 year follow-up. Patients were evaluated with patient-related outcome scores: modified Harris Hip Score, Nonarthritic Hip Score, and Hip Outcome Score–Sports Specific. Pain evaluation was performed using a visual analog scale.

There were significant differences in all studied variables when comparing pre- and postoperative scores. Yet, there were no differences in terms of patient-related outcome scores between the groups postoperatively. Postoperative visual analog scale scores averaged 2.1 for the AUITB group vs 1.9 for the ALTA group (P = .89); modified Harris Hip Score, 82.7 vs 83.3 (P = .77); Nonarthritic Hip Score, 81.1 vs 82.2 (P = .81); and Hip Outcome Score–Sports Specific, 81.6 vs 82.5 (P = .67).

No differences were found in terms of clinical outcomes between the 7-mm² ALTA graft and the 5-mm² AUITB graft. Both graft types and thicknesses might be considered comparable choices for primary reconstruction. Although a thicker-graft labral reconstruction seemed to have more ability to cover joint surface, clinical results did not show any superiority of a thicker graft whether it is autologous or allogenic.

Labral augmentation has emerged as an essential procedure to address a deficient or irreparable labrum while preserving native labral tissue and restoring the hip suction seal mechanism.

To evaluate midterm outcomes of arthroscopic hip labral augmentation for labral insufficiency after previous hip arthroscopy.

Case series; Level of evidence, 4.

Patients were identified from a prospectively collected database who underwent arthroscopic hip labral augmentation between January 2011 and January 2017 with a minimum 3-year follow-up. Pre- and postoperative patient-reported outcome scores were compared and included the 12-Item Short Form Health Survey physical and mental component summaries, Western Ontario and McMaster Universities Osteoarthritis Index, modified Harris Hip Score (mHHS), and Hip Outcome Score (HOS) (Activities of Daily Living [ADL] and Sport). Postoperative Tegner Activity Scale and patient satisfaction (1-10) scores were also evaluated. The minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) between the preoperative and minimum 3-year follow-up scores were calculated.

A total of 88 patients (39 men, 49 women) underwent revision hip arthroscopy with labral augmentation. The average age was 32.8 ± 11 years. Of these, 77 patients (88%) were available for the minimum 3-year follow-up. The survivorship (absence of conversion to total hip arthroplasty) at 3 years and 5 years was 93% at both time points, with a mean survival time of 8.5 years (95% CI, 8.0-8.9). Eleven patients (14%) required revision arthroscopic surgery for continued pain. Revisions occurred at a mean of 2.6 ± 1.4 years after augmentation. The mean follow-up was 5.2 ± 1.2 years (range, 3-9 years). For patients not requiring subsequent surgery (n = 61), all patient-reported outcome measures significantly improved, which included a 20-point increase in HOS-ADL (MCID, 82%; PASS, 72%) and mHHS (MCID, 78%; PASS, 70%). The median postoperative Tegner score was 4 (range, 1-10). The median postoperative patient satisfaction score was 9 out of 10 (range, 1-10).

Arthroscopic hip labral augmentation is a successful treatment option for patients with labral insufficiency after previous hip arthroscopy, demonstrating improved patient-reported outcomes and survivorship of 93% at 3 years and 5 years. This technique provides a valuable labral preservation option when addressing hip labral pathology when viable native labral tissue remains.

Corticosteroid treatments such as dexamethasone are commonly used to treat tendinopathy but with mixed outcomes. Although this treatment can cause tendon rupture, it can also stimulate the tendon to heal. However, the mechanisms behind corticosteroid treatment during tendon healing are yet to be understood.

To comprehend when and how dexamethasone treatment can ameliorate injured tendons by using a rat model of Achilles tendon healing.

Controlled laboratory study.

An overall 320 rats were used for a sequence of 6 experiments. We investigated whether the drug effect was time-, dose-, and load-dependent. Additionally, morphological data and drug administration routes were examined. Healing tendons were tested mechanically or used for histological examination 12 days after transection. Blood was collected for flow cytometry analysis in 1 experiment.

We found that the circadian rhythm and drug injection timing influenced the treatment outcome. Dexamethasone treatment at the right time point (days 7-11) and dose (0.1 mg/kg) significantly improved the material properties of the healing tendon, while the adverse effects were reduced. Local dexamethasone treatment did not lead to increased peak stress, but it triggered systemic granulocytosis and lymphopenia. Mechanical loading (full or moderate) is essential for the positive effects of dexamethasone, as complete unloading leads to the absence of improvements.

We conclude that dexamethasone treatment to improve Achilles tendon healing is dose- and time-dependent, and positive effects are perceived even in a partly unloaded condition.

These findings are promising from a clinical perspective, as the positive effect of this drug was seen even when given at lower doses and in a moderate loading condition, which better mimics the load level in patients with tendon ruptures.

Wnt/β-catenin signaling suppresses the differentiation of cultured tenocytes, but its roles in tendon repair remain mostly elusive. No chemical compounds are currently available to treat tendon injury.

We hypothesized that the inhibition of Wnt/β-catenin signaling would accelerate tendon healing.

Controlled laboratory study.

Tendon-derived cells (TDCs) were isolated from rat Achilles tendons. The right Achilles tendon was injured via a dermal punch, while the left tendon was sham operated. A Wnt/β-catenin inhibitor, IWR-1, and an antihistamine agent, promethazine (PH), were locally and intramuscularly injected, respectively, for 2 weeks after surgery. The healing tendons were histologically and biomechanically evaluated.

The amount of β-catenin protein was increased in the injured tendons from postoperative weeks 0.5 to 2. Inhibition of Wnt/β-catenin signaling by IWR-1 in healing tendons improved the histological abnormalities and decreased β-catenin, but it compromised the biomechanical properties. As we previously reported that antihistamine agents suppressed Wnt/β-catenin signaling in human chondrosarcoma cells, we examined the effects of antihistamines on TDCs. We found that a first-generation antihistamine agent, PH, increased the expression of the tendon marker genes Mkx and Tnmd in TDCs. Intramuscular injection of PH did not improve histological abnormalities, but it decreased β-catenin in healing tendons and increased the peak force and stiffness of the healing tendons on postoperative week 2. On postoperative week 8, however, the biomechanical properties of vehicle-treated tendons became similar to those of PH-treated tendons.

IWR-1 and PH suppressed Wnt/β-catenin signaling and improved the histological abnormalities of healing tendons. IWR-1, however, compromised the biomechanical properties of healing tendons, whereas PH improved them.

PH is a candidate repositioned drug that potentially accelerates tendon repair.

The pathoanatomy of glenoid labral articular disruption (GLAD) lesions has been inconsistently and poorly defined in the literature.

The purpose was to characterize GLAD lesions as they pertain to the pathoanatomy of labrum, cartilage, and bony structures, and to correlate findings with patient-reported outcomes (PROs). We hypothesized that greater degrees of bony and cartilaginous involvement would correlate with worse outcomes.

Case series; Level of evidence, 4.

All patients with a diagnosis of a GLAD lesion or a reverse GLAD (RGLAD) lesion at the time of diagnostic arthroscopy (January 2006–February 2019) were included in this study. Patients with ≥13.5% bone loss or previous ipsilateral shoulder surgery were excluded. Patient charts and operative reports/photos were used to identify the location of injury, extent of injury (labral, chondral, and bony), associated injuries, demographic factors, and treatment performed. Three injury patterns were identified: small (type 1), with no chondral defect after labral repair; large (type 2), with residual chondral defect after labral repair; and bony (type 3), with associated glenoid bone loss amenable to labral repair. Characterizations were cross-referenced to PROs at a mean follow-up of 5.5 years (range, 2.6-10.5 years): American Shoulder and Elbow Surgeons (ASES), Single Assessment Numeric Evaluation, shortened version of Disabilities of the Arm, Shoulder and Hand, and patient satisfaction.

In total, 50 patients were included, with 40 having GLAD and 10 having RGLAD lesions (mean age, 34.7 and 33.2 years, respectively). There were 14 (35%) type 1, 22 (55%) type 2, and 4 (10%) type 3 GLAD injuries. All PROs improved without any differences in the 3 subgroups postoperatively (ASES, 95.1 vs 91.3 vs 98.8, type 1, 2, and 3, respectively). RGLAD injuries were majority type 2 (7/10; 70%) with the remainder being type 1 (3/10; 30%).

With GLAD and RGLAD injuries, 3 distinct injury patterns can be observed correlating with the presence/absence of chondral loss after labral repair or the presence of associated bone loss. This descriptive characterization can facilitate arthroscopic treatment decisions. Future large studies are needed to determine if this is prognostic in nature.

Bony Bankart lesions can perpetuate chronic anterior glenohumeral instability. When surgical treatment is pursued, several factors need to be considered to obtain optimal outcomes.

To (1) quantitatively describe patterns of bone fragment resorption and associated risk factors for developing glenoid bone loss (GBL) and (2) to compare clinical and radiological results of attritional bone loss treated with either the arthroscopic Bankart or the open Latarjet procedure.

Cohort study; Level of evidence, 3.

A retrospective analysis of prospectively collected data was conducted for patients who underwent arthroscopic stabilization (group A1, 10%-20% GBL; group A2, >20% GBL) or open Latarjet (group B, >10% GBL) for recurrent shoulder instability with bony Bankart lesion. Patient characteristics, number of dislocations, and Western Ontario Shoulder Instability Index (WOSI) scores were obtained. Pre- and postoperative computed tomography imaging was used to quantitatively describe patterns of bone fragment resorption.

A total of 120 consecutive patients (group A1, 40; group A2, 23; group B, 57) were included in the study, with a mean age of 25.6 years (range, 19-35 years). The average follow-up was 5.0 years for all groups (range, 4.83-5.16 years in group A1, 4.58-5.41 years in group A2, and 4.33-5.67 years in group B). The mean times between dislocation event and surgery were 12.8 months (range, 6-32 months) and 13.6 months (range, 6-38 months) for groups A and B, respectively. Redislocation rates were 7.5% in group A1 versus 13.0% in group A2, and only occurred in patients with ≥13.5% GBL. There were no redislocations for group B (0%). Patients had better WOSI scores in group B (234.1 ± 126.9) than in group A (576.1 ± 224.6) (P < .0001). In group A, smaller preoperative bone fragment size displayed a higher percentage of resorption after surgery (r = −0.64; P < .05).

A significant inverse relationship exists between preoperative bone fragment size and percentage of postoperative resorption. Patients treated with arthroscopic bony Bankart repair who had final GBL ≥13.5% had worse outcomes. When planned GBL approaches 13.5% in high-demand patients, a smaller fragment size can result in worse clinical outcomes because of resorption. In these cases, choosing the open Latarjet procedure leads to better clinical results.

Autologous microfragmented lipoaspirate tissue has been recently introduced in orthopaedics as an easily available source of nonexpanded adipose-derived mesenchymal stem cells. Autologous microfragmented lipoaspirate tissue is expected to create a suitable microenvironment for tendon repair and regeneration. Rotator cuff tears show a high incidence of rerupture and represent an ideal target for nonexpanded mesenchymal stem cells.

To evaluate the safety and efficacy of autologous lipoaspirate tissue in arthroscopic rotator cuff repair.

Randomized controlled trial; Level of evidence, 2.

Consecutive patients referring to the investigation center for surgical treatment of magnetic resonance imaging–confirmed degenerative posterosuperior rotator cuff tears were assessed for eligibility. Those who were included were randomized to receive a single-row arthroscopic rotator cuff repair, followed by intraoperative injection of autologous microfragmented adipose tissue processed with an enzyme-free technology (treatment group) or not (control group). Clinical follow-up was conducted at 3, 6, 12, 18, and 24 months; at 18 months after surgery, magnetic resonance imaging of the operated shoulder was obtained to assess tendon integrity and rerupture rate.

An overall 177 patients were screened, and 44 (22 per group) completed the 24-month follow-up. A statistically significant difference in favor of the treatment group in terms of Constant-Murley score emerged at the primary endpoint at 6-month follow-up (mean ± SD; control group, 76.66 ± 10.77 points; treatment group, 82.78 ± 7.00 points; P = .0050). No significant differences in clinical outcome measures were encountered at any of the other follow-up points. No significant differences emerged between the groups in terms of rerupture rate, complication rate, and number of adverse events.

This prospective randomized controlled trial demonstrated that the intraoperative injection of autologous microfragmented adipose tissue is safe and effective in improving short-term clinical and functional results after single-row arthroscopic rotator cuff repair.

NCT02783352 (ClinicalTrials.gov identifier).

Mechanical stimulation and platelet-rich plasma (PRP) have been shown to be beneficial for healing of the bone-tendon interface (BTI), but few studies have explored the efficacy of a combination of these applications. We investigated the effect of mechanical stimulation combined with PRP on rotator cuff repair in mice.

Mechanical stimulation combined with PRP can enhance BTI healing in a murine model of rotator cuff repair.

Controlled laboratory study.

A total of 160 C57BL/6 mice were used. Overall, 40 mice were used to prepare PRP, while 120 mice underwent acute supraspinatus tendon (SST) repair. The animals were randomly assigned to 4 groups: control group, mechanical stimulation group, PRP group, and mechanical stimulation combined with PRP group (combination group). At 4 and 8 weeks postoperatively, animals were sacrificed, the eyeballs were removed to collect blood, and the SST–humeral complexes were collected. Histological, biomechanical, immunological, and bone morphometric tests were performed.

Histologically, at 4 and 8 weeks after surgery, the area of the fibrocartilage layer at the BTI in the combination group was larger than in the other groups. The content and distribution of proteoglycans in this layer in the combination group were significantly greater than in the other groups. At 8 weeks postoperatively, trabecular number, and trabecular bone thickness of the subchondral bone area of interest at the BTI of the combination group were greater than those of the other groups, bone volume fraction of the combination group was greater than the control group. On biomechanical testing at 4 and 8 weeks after surgery, the failure load and ultimate strength of the SST–humeral complex in the combination group were higher than in the other groups. Enzyme-linked immunosorbent assay results showed that, at 4 weeks postoperatively, the serum concentrations of transforming growth factor beta 1 and platelet-derived growth factor (PDGF) in the combination group were significantly higher than in the other groups; at 8 weeks, the PDGF-AB concentration in the combination group was higher than in the control and mechanical stimulation groups.

Mechanical stimulation combined with PRP can effectively promote the early stage of healing after a rotator cuff injury.

These findings imply that mechanical stimulation combined with PRP can serve as a potential therapeutic strategy for rotator cuff healing.

Performing open subpectoral biceps tenodesis in overhead athletes with a superior labrum anterior to posterior (SLAP) tear may affect their ability to return to overhead sports.

To investigate clinical outcomes in overhead athletes undergoing biceps tenodesis for the treatment of symptomatic, isolated SLAP tears involving the biceps-labral complex.

Case series; Level of evidence, 4.

A retrospective review of overhead athletes who underwent biceps tenodesis for a SLAP tear was performed. The American Shoulder and Elbow Surgeons (ASES) score, visual analog scale (VAS) score for pain, subjective shoulder value (SSV), patient satisfaction, willingness to undergo surgery again, revision procedures, and return to play were evaluated. Psychological readiness to return to sport was evaluated using the SLAP–Return to Sport after Injury (SLAP-RSI) score. A P value of <.05 was considered to be statistically significant.

The current study included 44 overhead athletes. The mean age was 34.9 years (range, 16-46 years), 79.5% were male, and the mean follow-up was 49.0 months (range, 18-107 months). Overall, 81.8% of patients returned to play their overhead sport after biceps tenodesis, and 59.1% of patients returned to the same or higher level of play. It took patients, on average, 8.7 months to return to play after biceps tenodesis. The mean SLAP-RSI score was 69.4, and 70.5% of patients passed the SLAP-RSI threshold of 56. The mean ASES score, VAS score, SSV, and satisfaction were 92.0, 0.8, 80.6, and 87.9%, respectively. No patients in our cohort required revision surgery.

This study found that athletes undergoing biceps tenodesis for the treatment of a symptomatic, isolated SLAP tear had a high rate of return to play, good functional outcomes, and a low rate of revision surgery.

Current techniques for ulnar collateral ligament (UCL) reconstruction do not reproduce the anatomic ulnar footprint of the UCL. The purpose of this study was to describe a novel UCL reconstruction technique that utilizes proximal-to-distal ulnar bone tunnels to better re-create the anatomy of the UCL and to compare the biomechanical profile at time zero among this technique, the native UCL, and the traditional docking technique.

The biomechanical profile of the anatomic technique is similar to the native UCL and traditional docking technique.

Controlled laboratory study.

Ten matched cadaveric elbows were potted with the forearm in neutral rotation. The palmaris longus tendon graft was harvested, and bones were sectioned 14 cm proximal and distal to the elbow joint. Specimen testing included (1) native UCL testing performed at 90° of flexion with 0.5 N·m of valgus moment preload, (2) cyclic loading from 0.5 to 5 N·m of valgus moment for 1000 cycles at 1 Hz, and (3) load to failure at 0.2 mm/s. Elbows then underwent UCL reconstruction with 1 elbow of each pair receiving the classic docking technique using either anatomic (proximal to distal) or traditional (anterior to posterior) tunnel locations. Specimen testing was then repeated as described.

There were no differences in maximum load at failure between the anatomic and traditional tunnel location techniques (mean ± SD, 34.90 ± 10.65 vs 37.28 ± 14.26 N·m; P = .644) or when including the native UCL (45.83 ± 17.03 N·m; P = .099). Additionally, there were no differences in valgus angle after 1000 cycles across the anatomic technique (4.58°± 1.47°), traditional technique (4.08°± 1.28°), and native UCL (4.07°± 1.99°). The anatomic group and the native UCL had similar valgus angles at failure (24.13°± 5.86° vs 20.13°± 5.70°; P = .083), while the traditional group had a higher valgus angle at failure when compared with the native UCL (24.88°± 6.18° vs 19.44°± 5.86°; P = .015).

In this cadaveric model, UCL reconstruction with the docking technique utilizing proximal-to-distal ulnar tunnels better restored the ulnar footprint while providing valgus stability comparable with reconstruction with the docking technique using traditional anterior-to-posterior ulnar tunnel locations. These results suggest that utilization of the anatomic tunnel location in UCL reconstruction has similar biomechanical properties to the traditional method at the time of initial fixation (ie, not accounting for healing after reconstruction in vivo) while keeping the ulnar tunnels farther from the ulnar nerve. Further studies are warranted to determine if an anatomically based UCL reconstruction results in differing outcomes than traditional reconstruction techniques.

Current UCL reconstruction techniques do not accurately re-create the ulnar UCL footprint. The UCL is a dynamic constraint to valgus loads at the elbow, and a more anatomic reconstruction may afford more natural joint kinematics. This more anatomic technique performs similarly to the traditional docking technique at time zero, and the results of this study may offer a starting point for future in vivo studies.

Acute adaptations in clinical measures of range of motion and strength have been found after baseball pitching; however, there is a lack of research concerning the physiological mechanism responsible for these changes. Adaptations in muscle architecture of the infraspinatus and teres minor may serve as the structural changes responsible for these clinical measure changes.

To longitudinally assess the acute changes in range of motion, strength, and muscle architecture of the infraspinatus and teres minor muscles in baseball pitchers after a simulated baseball game. Additionally, we examined the relationship between muscle architecture and changes in clinical measures of range of motion and strength.

Controlled laboratory study.

Ten healthy nonvarsity collegiate club baseball pitchers (mean ± SD; age, 20.1 ± 1.10 years) were examined pre-pitching, immediately after pitching, and each subsequent day for 5 days after pitching in a simulated baseball game. A digital inclinometer and handheld dynamometer were used to assess range of motion and strength, respectively. Diagnostic ultrasound was used to assess pennation angle and muscle thickness of the infraspinatus and teres minor at rest and at maximal contraction.

Internal rotation range of motion significantly decreased immediately and did not return to baseline until 4 days after pitching (P≤ .05). External rotation strength also immediately decreased and returned on the third day after pitching (P≤ .05). Moreover, the resting pennation angle of the superficial and deep portions of the infraspinatus increased immediately after pitching, with the superficial portion returning to baseline on day 4 and the deep portion returning on day 5 (P≤ .05). Furthermore, the pennation angle changes of the infraspinatus and thickness of the teres minor were predictive of the loss of internal rotation range of motion after pitching (R² = 0.419; P≤ .05).

This study found diminished internal rotation range of motion and external rotation strength after pitching, with alterations in muscle architecture of the infraspinatus. The pennation angle increase in the infraspinatus at rest is indicative of increased tension in the muscle, which was found to be the underlying mechanism for the clinical loss of internal rotation range of motion. This was demonstrated by the inverse relationship between internal rotation range of motion and the pennation angle of the superficial and deep fibers of the infraspinatus.

Clinicians should consider recovery time after pitching to prevent chronic losses of shoulder range of motion and strength. Identification of the underlying mechanisms of range of motion loss after pitching allows clinicians to optimize recovery strategies in baseball pitchers.

Intra-articular injections of human mesenchymal stromal cells (hMSCs) have shown promise in slowing cartilage degradation in posttraumatic osteoarthritis (PTOA). Clinical use of cell therapies for osteoarthritis has accelerated in recent years without sufficient scientific evidence defining best-use practices. Common recommendations advise patients to avoid nonsteroidal anti-inflammatory drug (NSAID) use before and after cell injection over concerns that NSAIDs may affect therapeutic efficacy. Recommendations to restrict NSAID use are challenging for patients, and it is unclear if patients are compliant.

NSAIDs will reduce the efficacy of hMSC therapy in treating a preclinical model of PTOA.

Controlled laboratory study.

Lewis rats underwent medial meniscal transection (MMT) surgery to induce PTOA or a sham (sham group) surgery that did not progress to PTOA. Rats received naproxen solution orally daily before (Pre-NSAID group) or after (Post-NSAID group) hMSC treatment, throughout the course of the experiment (Full-NSAID group), or received hMSCs without NSAIDs (No NSAID). Cartilage morphology and composition were quantified using contrast-enhanced micro–computed tomography and histology. Pain (secondary allodynia) was measured using a von Frey filament.

Injection of hMSCs attenuated cartilage degeneration associated with MMT. hMSCs prevented proteoglycan loss, maintained smooth cartilage surfaces, reduced cartilage lesions, reduced mineralized osteophyte formation, and reduced pain by week 7. The Pre-NSAID group had decreased proteoglycan levels compared with the hMSC group, although there were no other significant differences. Thus, pretreatment with NSAIDs had minimal effects on the therapeutic benefits of hMSC injections. The Post-NSAID and Full-NSAID groups, however, exhibited significantly worse osteoarthritis than the hMSC-only group, with greater proteoglycan loss, surface roughness, osteophyte volume, and pain.

Use of NSAIDs before hMSC injection minimally reduced the therapeutic benefits for PTOA, which included preservation of cartilage surface integrity as well as a reduction in osteophytes. Use of NSAIDs after injections, however, substantially reduced the therapeutic efficacy of cellular treatment.

Our data support the clinical recommendation of avoiding NSAID use after hMSC injection but suggest that using NSAIDs before treatment may not substantially diminish the therapeutic efficacy of cell treatment.

Various cell-free scaffolds are already in use for the treatment of osteochondral defects (OCDs); however, a gold standard material has not yet been defined.

This study compared the macroscopic, histological, and scanning electron microscopy (SEM) characteristics of Chondro-Gide (CG), MaioRegen (MA), and poly-d,l-lactide-co-caprolactone (PLCL) cell-free scaffolds enhanced with small-diameter microfractures (SDMs) for OCDs in a rabbit model.

Controlled laboratory study.

In total, 54 knees from 27 rabbits were used in this study. Three rabbits were sacrificed at the beginning of the study to form an intact cartilage control group (group IC). An OCD model was created at the center of the trochlea, and SDMs were generated in 24 rabbits. Rabbits with OCDs were divided into 4 groups (n = 12 knees per group) according to the cell-free scaffold applied: CG (group CG), MA (group MA), PLCL (group PLCL), and a control group (group SDM). Half of the rabbits were sacrificed at 1 month after treatment, while the other half were sacrificed at 3 months after treatment. Healed cartilage was evaluated macroscopically (using International Cartilage Regeneration & Joint Preservation Society [ICRS] classification criteria) and histopathologically (using modified O’Driscoll scores and collagen staining). Additionally, cell-free scaffold morphologies were compared using SEM analysis.

ICRS and modified O’Driscoll classification and staining with collagen type 1 and type 2 demonstrated significant differences among groups at both 1 and 3 months after treatment (P < .05). The histological characteristics of the group IC samples were superior to those of all other groups, except group PLCL, at 3 months after treatment (P < .05). In addition, the histological properties of group PLCL samples were superior to those of group SDM samples at both 1 and 3 months after treatment in terms of the modified O’Driscoll scores and type 1 collagen staining (P < .05). Concerning type 2 collagen staining intensity, the groups were ranked from highest to lowest at 3 months after treatment as follows: group PLCL (30.3 ± 2.6) > group MA (26.6 ± 1.2) > group CG (23.3 ± 2.3) > group SDM (18.9 ± 0.9).

OCDs treated with enhanced SDM using cell-free PLCL scaffolds had superior histopathological and microenvironmental properties, more hyaline cartilage, and more type 2 collagen compared with those treated using CG or MA scaffolds.

OCDs treated with PLCL cell-free scaffolds may have superior histopathological properties and contain more type 2 collagen than do OCDs treated with CG or MA cell-free scaffolds.

Inconsistent findings exist between drive-leg ground-reaction forces (GRFs) and pitching mechanics. Previous literature has largely reported drive-leg mechanics and GRFs at the start of the pushoff phase for their role in initiating force development. Little research has assessed drive-leg kinematics that includes a pitcher’s windup motion to determine its effects on subsequent phases in the pitching motion.

The primary aim was to analyze the relationship between drive-leg knee valgus angle during the windup and subsequent pitching mechanics. We hypothesized that the drive-leg knee valgus angle during the early portion of the pitching motion would alter later phases’ pitching mechanics. A secondary aim was to assess GRFs to determine if the drive-leg knee valgus angle was associated with changes in force. We hypothesized that an increased drive-leg knee valgus angle would increase GRFs during the pitching motion.

Descriptive laboratory study.

A total of 17 high school baseball pitchers (mean age, 16.1 ± 0.9 years; mean height, 180.0 ± 4.8 cm; mean weight, 75.5 ± 7.5 kg) volunteered for the study. Kinematic data and GRFs were collected using an electromagnetic tracking system and force plates. Pitchers threw maximal-effort fastballs from a mound at regulation distance. The drive-leg knee valgus angle was analyzed during the windup and pushoff phases of the pitch to determine its effects on other biomechanical variables throughout the pitching motion.

There was a significant relationship between drive-leg knee valgus angle during the windup (Fchange 1,12) = 16.13; P = .002; R² = 0.695) and lateral GRF in the arm-cocking phase. Additionally, there was a significant relationship between drive-leg knee valgus angle during pushoff (Fchange(2,11) = 10.21; P = .003; R² = 0.716) and lateral GRF in the arm-cocking phase and pitching-elbow valgus moment in the acceleration phase.

Drive-leg knee valgus angle during the windup and pushoff had a significant relationship with drive-leg GRF and pitching-elbow valgus moment at later stages of the pitching cycle.

Assessments of drive-leg kinematics during the windup and pushoff may be useful in identifying inefficient movement patterns that can have an effect on the direction of a pitcher’s drive-leg force contribution, which can lead to increased forces on the throwing elbow.

Numerous studies have reported the incidence and outcomes of injuries in the men’s and women’s National Basketball Association (NBA and WNBA, respectively).

To synthesize published data regarding the incidence and outcomes of all injuries in the NBA and WNBA in a comprehensive review.

Systematic review; Level of evidence, 4.

Following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, we searched 3 electronic databases (PubMed, MEDLINE, Embase) for studies of all levels of evidence since 1990 pertaining to injuries sustained by active players in the NBA and WNBA. Studies were excluded if the cohort of interest included ≤3 active players.

The initial search of the 3 databases yielded 1253 unique studies, of which 49 met final inclusion criteria for this review. Only 4 studies included athletes in the WNBA. Based on the mean annual incidence, the 5 most common orthopaedic sports injuries sustained in the NBA were concussions (9.5-14.9 per year), fractures of the hand (3.5-5.5 per year), lower extremity stress fractures (4.8 per year), meniscal tears (2.3-3.3 per year), and anterior cruciate ligament tears (1.5-2.6 per year). Cartilage defects treated using microfracture, Achilles tendon ruptures, and anterior cruciate ligament injuries were 3 injuries that led to significant reductions in performance measurements after injury.

With advances in sports technology and statistical analysis, there is rapidly growing interest in injuries among professional basketball athletes. High-quality prospective studies are needed to understand the prevalence and effect of injuries on player performance and career length. This information can inform preventative and treatment measures taken by health care providers to protect players and guide safe return to play at a high level.

Growth disturbance is an uncommon but potentially serious complication after anterior cruciate ligament (ACL) reconstruction in skeletally immature patients.

To describe how the pediatric ACL literature has assessed preoperative skeletal maturity and the amount of growth remaining and to comprehensively review the incidence, reporting, and monitoring of postoperative growth disturbance.

Systematic review; Level of evidence, 4.

This review included studies reporting original research of clinical outcomes of skeletally immature patients after ACL reconstruction. Patient characteristics, surgical techniques, preoperative assessments of skeletal maturity or growth remaining, and postoperative assessments of growth disturbances were extracted.

A total of 100 studies met inclusion criteria. All studies reported chronological age, and 28 studies (28%) assessed skeletal age. A total of 44 studies (44%) used Tanner staging, and 12 studies (12%) obtained standing hip-to-ankle radiographs preoperatively. In total, 42 patients (2.1%) demonstrated a leg length discrepancy (LLD) >10 mm postoperatively, including 9 patients (0.5%) with LLD >20 mm; furthermore, 11 patients (0.6%) with LLD underwent growth modulation. Shortening was the most common deformity overall, but overgrowth was reported more frequently in patients who had undergone all-epiphyseal techniques. Most LLDs involved the femur (83%). A total of 26 patients (1.3%) demonstrated a postoperative angular deformity ≥5°, and 9 of these patients underwent growth modulation. The most common deformities were femoral valgus (41%), tibial recurvatum (33%), and tibial varus (22%). Although standing hip-to-ankle radiographs were the most common radiographic assessment of growth disturbance, most studies inadequately reported the clinical and radiographic methods of assessment for growth disturbance. Additionally, only 35% of studies explicitly followed patients to skeletal maturity.

This systematic review described significant variability in the reporting and monitoring of growth-related complications after ACL reconstruction in skeletally immature patients. The incidence of LLD and angular deformity appeared to be low, but the quality of research was not comprehensive enough for accurate assessment.

CRD42019136059 (PROSPERO)

Tissue adhesives (TAs) represent a promising alternative or augmentation method to conventional tissue repair techniques. In sports medicine, TA use has been suggested and implemented in the treatment of meniscal tears. The aim of this review was to present and discuss the current evidence and base of knowledge regarding the clinical usage of TAs for meniscal repair.

Systematic review; Level of evidence, 4.

A systematic literature search was performed using the PubMed, Embase, and Cochrane Library databases for studies reporting on clinical outcomes of TA usage for meniscal repair in humans in the English language published before January 2020.

Ten studies were eligible for review and included 352 meniscal repairs: 94 (27%) were TA-based repairs and 258 (73%) were combined suture and TA repairs. Concomitant anterior cruciate ligament reconstruction was performed in 224 repairs (64%). All included studies utilized fibrin-based TA. Of the 10 studies, 9 were evidence level 4 (case series), and 8 reported on a cohort of ≤40 meniscal repairs. Rates of meniscal healing were evaluated in 9 of 10 studies, with repair failure seen in 39 repairs (11%).

The use of TAs, specifically fibrin-based TAs, for meniscal repair shows good results as either an augmentation or primary repair of various configurations of meniscal tears. However, this review reveals an absence of comparative high-quality evidence supporting the routine use of TAs for meniscal repair and emphasizes the lack of an ideal TA designed for that purpose. Further high-quality research, basic science and clinical, will facilitate the development of new materials and enable testing their suitability for use in meniscal repair.

Knee injection using either bone marrow aspirate concentrate (BMAC) or stromal vascular fraction (SVF) from adipose tissue has been shown to result in symptomatic improvement in patients with knee osteoarthritis (OA). It is still unclear whether one of these therapies is superior over the other.

To systematically report the clinical studies evaluating BMAC and SVF in the treatment of knee OA and to compare the clinical efficacy of these 2 injection therapies.

Meta-analysis; Level of evidence, 4.

This meta-analysis was performed per the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines. Studies were included if they reported the clinical outcomes after a single BMAC or SVF injection in the knee joint of patients with OA. Studies evaluating preparations of culture-expanded stem cells were excluded. A random effects model was used; the clinical efficacy of BMAC or SVF injection was assessed using the standardized mean difference (SMD) and compared. Visual analog scale (VAS) scores for pain and Western Ontario and McMaster Universities Osteoarthritis (WOMAC) knee index were the primary outcomes. The level of statistical significance was set at P < .05.

Ten studies and 472 patients with knee OA who received either BMAC (233 patients) or SVF (239 patients) were included. Patients who received an injection had improved VAS outcomes (mean ± SD): from 5.8 ± 1.3 to 2.6 ± 17 for BMAC and from 6.4 ± 1.4 to 3.4 ± 0.5 for SVF. They also experienced significantly reduced pain (SMD [VAS], 2.6 for BMAC and 3.4 for SVF) and improved function (SMD [WOMAC], 1.4 for BMAC and 1.2 for SVF). However, the SVF injection had a significantly greater effect on pain reduction than did the BMAC injection (P < .0001). Based on WOMAC, the clinical effect of BMAC versus SVF knee injection in patients with knee OA was equivalent (P = .626). Results were limited by the presence of publication bias as well as variability in the preparation methods utilized in the BMAC and SVF injection protocols. Complications were reported in 50% of the BMAC studies (knee stiffness, persistent knee swelling) and 67% of the SVF studies (knee swelling, knee pain, positive SVF cultures without symptoms of infection, and bleeding at the abdominal harvest site).

A single BMAC or SVF injection into the knee joint of patients with OA resulted in symptomatic improvement at short-term follow-up. However, SVF seemed to be more effective than did BMAC in the reduction of knee pain. There was significant variation in the BMAC and SVF injection preparation techniques used across the studies and a lack of stratification of outcomes based on the radiologic classification of OA. Therefore, these results should be taken with caution.