Jacqueline M. Brady

The effect of menstrual cycle and contraceptives on ACL injuries and laxity: A Systematic Review and Meta-analysis

Background: Women are at substantially greater risk for anterior cruciate ligament (ACL) injuries than are men. Purpose: To conduct a systematic review and meta-analysis of the literature to clarify the effect of the menstrual cycle and contraceptives on the laxity of and noncontact injuries to the ACL. Study Design: Systematic review; Level of evidence, 4. Methods: Searches were conducted using MEDLINE (1946–August 2016), the Cochrane Library Database, clinical trial registries, and related reference lists. Search terms included athletic injuries, knee injuries, ligaments, joint instability, menstrual cycle, ovulation, hormones, and contraceptives. Investigators independently dually abstracted and reviewed study details and quality using predefined criteria and evaluated overall strength of evidence using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) criteria. Results: Twenty-one studies totaling 68,758 participants were included: 5 on the menstrual cycle and ACL injury, 7 on hormonal contraceptives and ACL injury, as well as 13 on menstrual cycle and ligament laxity. Four of 5 studies of women not using hormonal contraception indicated that the luteal phase was the least associated with ACL injuries. The 2 largest and highest quality studies on hormonal contraceptives suggested that hormonal contraceptives may be protective against ACL injury. Six of 12 studies on ACL laxity provided quantitative data for meta-analysis, finding significantly increased laxity during the ovulatory phase compared with the follicular phase. Conclusion: The literature suggests an association between hormonal fluctuations and ACL injury. Recent studies have suggested that oral contraceptives may offer up to a 20% reduction in risk of injury. The literature on ACL injuries and the menstrual cycle has more than doubled over the past decade, permitting quantitative analysis for the first time. However, the overall strength of this evidence is low. Promising potential directions for future research include long-term observational studies with ongoing hormonal assays and large interventional trials of follicular suppression, including newer hormonal methods.

Clinical Outcomes After Isolated Medial Patellofemoral Ligament Reconstruction for Patellar Instability Among Patients With Trochlear Dysplasia

Background: Medial patellofemoral ligament (MPFL) reconstruction has become one of the most common and widely used procedures to regain stability among patients with recurrent lateral patellar dislocation. While recent studies demonstrated low recurrence rates, improved patient-reported outcome measures, and a high rate of return to sports, limited literature explored its effectiveness as an isolated intervention in the context of trochlear dysplasia. Purpose: To determine the efficacy of isolated MPFL reconstruction in treating patellar instability in the setting of trochlear dysplasia. Study Design: Case series; Level of evidence, 4. Methods: This was a retrospective review of consecutive patients who underwent uni- or bilateral medial patellofemoral ligament reconstruction for patellofemoral instability with a minimum 2-year follow-up. No osteotomies were included. Pre- and postoperative assessment included ligamentous laxity, patellar crepitus, tilt, translation, apprehension, and radiographic features, including tibial tubercle-trochlear groove (TT-TG) distance, Dejour classification, and Caton-Deschamps index. Results: A total of 121 MPFL reconstructions were included. Mean age at surgery was 23.8 years, and 4.4 dislocation events occurred before surgery. Mean follow-up was 44 months; 76% of patients were female. Mean preoperative TT-TG ratio was 13.5, and mean Caton-Deschamps ratio was 1.2; 92% of patients had Dejour B, C, or D trochlear dysplasia. Kujala score improved from 55.0 preoperatively to 90.0 (P < .001). Almost all patients (94.5%) were able to return to sports at 1 year, with 74% returning to the same or higher level of play. Only 3 patients reported a postoperative dislocation or subluxation event. Discussion: For patients without significantly elevated TT-TG distances or significant patella alta, isolated MPFL reconstruction provides a safe and effective treatment for patellofemoral instability, despite the presence of trochlear dysplasia. Most patients are able to return to sports by 1 year postoperatively at the same or higher level of play.

The Tibial Tubercle–to–Trochlear Groove Distance Is Reliable in the Setting of Trochlear Dysplasia, and Superior to the Tibial Tubercle–to–Posterior Cruciate Ligament Distance When Evaluating Coronal Malalignment in Patellofemoral Instability

PURPOSEnTo determine best practices for consistent and accurate evaluation of coronal alignment in patients with patellofemoral (PF) instability.nnnMETHODSnSix reviewers examined 239 knee magnetic resonance images (MRIs) in patients with PF instability and anterior cruciate ligament (ACL) rupture. Measurements included tibial tubercle-to-trochlear groove (TT-TG) distance measured at the most proximal and distal portions of the trochlea, tibial tubercle-to-PCL (TT-PCL) distance, and Dejour classification of trochlear dysplasia.nnnRESULTSnInterrater reliability was low for Dejour classification (kxa0= 0.289), but improved to moderate (kxa0= 0.448) when patients were separated into normal/Dejour A and Dejour B/C/D. Interrater reliability was high for proximal and distal TT-TG measurements (interclass correlation coefficients [ICCs]xa0= 0.807 and 0.936, respectively). TT-PCL was moderately reliable (ICCxa0= 0.625), and correlated with TT-TG (rxa0= 0.457, P < .001 proximal and rxa0= 0.451, P < .001 distal). No significant difference was found between the proximal and distal measurements of TT-TG in each patient, though the PF group exhibited higher values than the ACL group (P < .001 for both). TT-PCL was significantly higher for the PF group than the ACL group (Pxa0=xa0.015), but this difference lost significance when the group was divided by the TT-PCL cutoff of 24xa0mmxa0(Pxa0= .371).nnnCONCLUSIONSnThe proximal and distal techniques for measuring the TT-TG distance are similar to each other, and reliable despite level of reviewer training or presence of dysplasia. The TT-TG distance was predictive of patellofemoral instability. The TT-PCL distance was found to be less reliable than either method of measuring the TT-TG distance. Thus, this study demonstrated TT-TG to be superior to TT-PCL as a measurement of coronal malalignment. Given the variability in Dejour classification in this and other studies, a more reliable classification system for trochlear dysplasia as defined on cross-sectional imaging is warranted.nnnLEVEL OF EVIDENCEnLevel III, retrospective clinical trial.

Anisometry of Medial Patellofemoral Ligament Reconstruction in the Setting of Increased Tibial Tubercle–Trochlear Groove Distance and Patella Alta

PURPOSEnTo assess the impact elevated tibial tubercle-trochlear groove (TT-TG) distance and patella height, as measured by the Caton-Deschamps Index (CDI), have on the isometry of a reconstructed medial patellofemoral ligament (MPFL).nnnMETHODSnNine fresh-frozen cadaveric knees were placed on a custom testing fixture, with a fixed femur and a mobile tibia. A suture fixed to the MPFL origin on the patella and free to move at the Schöttle point on the femur represented a reconstructed MPFL. A local coordinate system was established, and retroreflective markers attached to the suture quantified MPFL length changes by use of a 3-dimensional motion capture system. The tubercle was transferred to create TT-TG distances of 20xa0mm and 25xa0mm and CDIs of 1.2 and 1.4 (patella alta). Recordings of the MPFL suture length change as the knee was brought through a range of motion were made using all combinations of tubercle anatomy in a randomized order for each specimen. A generalized estimating equation modeling technique was used to analyze and control for the clustered nature of the data.nnnRESULTSnKnees with native tibial tubercle anatomy showed MPFL isometry through 20° to 70° range of motion. Tibial tubercle lateralization (increased TT-TG distance) significantly altered MPFL isometry with a TT-TG distance of 20xa0mmxa0(P < .0001). Patella alta significantly altered MPFL isometry with a CDI of 1.2 (Pxa0= .0182). The interaction of tibial tubercle lateralization combined with patella alta significantly increased the amount of anisometry seen in the reconstructed MPFL (P < .001).nnnCONCLUSIONSnIncreased tibial tubercle lateralization and patella alta produce anisometry in an MPFL reconstruction using currently recommended landmarks, leading to potentially increased graft tension and potential failure.nnnCLINICAL RELEVANCEnTibial tubercle transfer should be considered when performing an MPFL reconstruction for recurrent patellofemoral instability in the setting of significant patella alta and an elevated TT-TG distance-especially when both are present-because an isolated MPFL reconstruction will be prone to failure given the anisometry shown in this study.

Magnetic Resonance Imaging Validation of Tibial Tubercle Transfer Distance in the Fulkerson Osteotomy: A Clinical and Cadaveric Study

PURPOSEnTo validate the medialization and anteriorization distances, and the osteotomy angle of anteromedialization tibial tubercle osteotomies using postoperative axial imaging.nnnMETHODSnFrom March 2004 to August 2015, 117 consecutive patients who underwent anteromedialization osteotomies of the tibial tubercle by a single surgeon were identified. Only patients with pre- and postoperative magnetic resonance imaging (MRI) studies were included. Using MRI multiplanar reformats, distances that the tibial tubercle was translated medially (medialization) and anteriorly (anteriorization) were measured. In addition, the osteotomy angle was measured on the postoperative MRI. The measured values were compared with intraoperative estimates. Tibial tubercle osteotomies were then performed on 3 cadaveric knee specimens and imaged with pre- and postprocedure MRIs to correlate intraoperative measurements with MRI findings.nnnRESULTSnA total of 40 patients (41 knees) (34.2%) had both pre- and postoperative MRIs and were included. Compared with intraoperative assessment, MRI measured medialization values average 94.7% (standard deviation [SD] 37.7) of dictated values (Pxa0= .1). MRI measured anteriorization averaged less than half of dictated values (48.9%, SD 18.2%, P < .0001). MRI measured osteotomy angles averaged 67.2% of dictated values (SD 50.3%, P < .0001). The steepest osteotomy angle that could be performed without violating the posterior cortex and/or endangering the posterior neurovascular structures was 46.3°.nnnCONCLUSIONSnSurgeons often overestimate both the anteriorization distance and the osteotomy angle in anteromedialization tibial tubercle osteotomies. The steepest osteotomy angle is less than the 60° described in the literature. Modifications should be considered when more anteriorization is desired with tubercle transfers.nnnLEVEL OF EVIDENCEnLevel IV, retrospective case series.

Wearable Inertial Sensors Allow for Quantitative Assessment of Shoulder and Elbow Kinematics in a Cadaveric Knee Arthroscopy Model

PURPOSEnTo develop a model using wearable inertial sensors to assess the performance of orthopaedic residents while performing a diagnostic knee arthroscopy.nnnMETHODSnFourteen subjects performed a diagnostic arthroscopy on a cadaveric right knee. Participants were divided into novices (5 postgraduate year 3 residents), intermediates (5 postgraduate year 4 residents), and experts (4 faculty) based on experience. Arm movement data were collected by inertial measurement units (Opal sensors) by securing 2 sensors to each upper extremity (dorsal forearm and lateral arm) and 2 sensors to the trunk (sternum and lumbar spine). Kinematics of the elbow and shoulder joints were calculated from the inertial data by biomechanical modeling based on a sequence of links connected by joints. Range of motion required to complete the procedure was calculated for each group. Histograms were used to compare the distribution of joint positions for an expert, intermediate, and novice.nnnRESULTSnFor both the right and left upper extremities, skill level corresponded well with shoulder abduction-adduction and elbow prono-supination. Novices required on average 17.2° more motion in the right shoulder abduction-adduction plane than experts to complete the diagnostic arthroscopy (Pxa0= .03). For right elbow prono-supination (probe hand), novices required on average 23.7° more motion than experts to complete the procedure (Pxa0= .03). Histogram data showed novices had markedly more variability in shoulder abduction-adduction and elbow prono-supination compared with the other groups.nnnCONCLUSIONSnOur data show wearable inertial sensors can measure joint kinematics during diagnostic knee arthroscopy. Range-of-motion data in the shoulder and elbow correlated inversely with arthroscopic experience. Motion pattern-based analysis shows promise as a metric of resident skill acquisition and development in arthroscopy.nnnCLINICAL RELEVANCEnWearable inertial sensors show promise as metrics of arthroscopic skill acquisition among residents.

A biomechanical comparison of all-inside cruciate ligament graft preparation techniques

BackgroundThe all-inside cruciate ligament graft preparation technique has become popular due to its utility in sparing a growing physis, preserving a tendon in ACL surgery, and/or reduction of pain. However, few studies have compared graft preparation techniques to determine the ideal construct for cruciate ligament reconstruction. We sought to compare biomechanical properties of two quadrupled all-inside cruciate ligament graft preparation techniques and three alternative all-inside graft preparation techniques that may be used when the available tendon is too short to be quadrupled.MethodsFifty porcine extensor tendons were evenly divided into five groups (nu2009=u200910) representing all-inside graft preparation techniques, including two quadrupled (Quad-A, Quad-B) and three alternative methods (Tripled, Folded, Two-Doubled). Each graft construct underwent preconditioning (10 loading cycles from 20 to 50xa0N at 0.1xa0Hz), cyclic loading (500 loading cycles from 50 to 250xa0N at 1.0xa0Hz) and load-to-failure (tension applied at 20xa0mm/min).ResultsQuad-A and Quad-B demonstrated no significant differences in cyclic displacement (10.5u2009±u20090.3 vs 11.7u2009±u20090.4xa0mm; pu2009=u20090.915), cyclic stiffness (1086.2u2009±u2009487.3 vs 460.4u2009±u200971.4xa0N/mm; pu2009=u20090.290), pullout stiffness (15.9u2009±u20094.3 vs 7.4u2009±u20094.4xa0N/mm; pu2009=u20090.443), ultimate failure load (641.2u2009±u200984.7 vs 405.9u2009±u2009237.4xa0N; pu2009=u20090.672), or ultimate failure displacement (47.3u2009±u20096.7 vs 55.5u2009±u20090.7xa0mm; pu2009=u20090.778). The mean cyclic displacement of the Two-Doubled group was significantly greater than the Quad-A (29.7u2009±u20092.2 vs 10.5u2009±u20090.3xa0mm; pu2009<u20090.001), Quad-B (29.7u2009±u20092.2 vs 11.7u2009±u20090.4xa0mm; pu2009<u20090.001), Tripled (29.7u2009±u20092.2 vs 11.3u2009±u20090.2xa0mm; pu2009<u20090.001), and Folded group (29.7u2009±u20092.2 vs 13.3u2009±u20090.2xa0mm; pu2009<u20090.001). There were no other statistically significant differences between the three alternative all-inside graft preparation techniques.ConclusionThe current study demonstrates the biomechanical properties of two quadrupled all-inside graft constructs, Quad-A and Quad-B, are not significantly different. When the available tendon is of insufficient length, the Two-Doubled group demonstrated more than twice the cyclic displacement of all other graft preparation techniques, and is therefore not recommended for use in all-inside cruciate ligament reconstruction.

Firefighters Have a Higher Incidence of Trochlear Chondral Lesions than the Normal Population

BackgroundFirefighters’ knees are subjected to significant dynamic and static forces, resulting in increased knee complaints and a higher relative risk of osteoarthrosis, compared with aged-matched office workers. Firefighters wear or carry a total of 80 to 100 lbs. of gear while performing intensive physical activity.Purpose/QuestionThe purpose of this study was to determine whether a central femoral trochlear lesion was observed in firefighters undergoing knee arthroscopy for other diagnoses.MethodsA retrospective chart review of 159 knees in 146 firefighters undergoing arthroscopy for treatment of acute meniscal injury or anterior cruciate ligament reconstruction over a 14-year period was undertaken. Patient demographics, physical examination results, trochlear lesion size and grade, and firehouse type (engine vs. ladder company) and firefighter position (seniority) were recorded. Comparisons of characteristics in those with and without trochlear lesions were performed.ResultsThe average patient age was 42.2xa0years (range, 27 to 64xa0years). Ninety-eight knees (62%) had trochlear lesions and 33 knees (51%) had matching patellar lesions. Patients with lesions were older (43.2 vs. 40.5xa0years). Mean trochlear lesion size was 19.5u2009±u200913.7xa0mm by 18.9u2009±u200912.4xa0mm. Lesion grade distribution was grade 1 or 2 in 24 knees (24%) and grade 3 or 4 in 67 knees (44%). Trochlear lesion presence was associated with a body mass index of over 30. Current engine company members had more advanced lesions.ConclusionsA “firefighter’s trochlea” was present in the majority of firefighters undergoing knee arthroscopy. Higher age and longer tenure as a firefighter prior to surgery were associated with more advanced lesions. Firefighters working in engine companies at the time of arthroscopy were at a greater risk of developing low-grade lesions but not high-grade lesions. Firefighters move between ladder and engine companies, thus a definitive association with company type cannot be reached in this retrospective study. This lesion may reflect the increase in patellofemoral biomechanical stresses secondary to the physical demands of the occupation.

Use of TT-PCL versus TT-TG

Purpose of ReviewThe tibial tubercle-to-trochlear groove (TT-TG) distance and tibial tubercle-to-posterior cruciate ligament (TT-PCL) distance have both been proposed for use in the evaluation of patients with patellofemoral instability.Recent FindingsWhile the TT-TG value may be confounded by several factors, including age, gender, body mass index, and varying degrees of knee flexion on cross-sectional imaging, recent literature supports its utility for differentiation of patients with and without patellofemoral instability, and stratification of patients with and without coronal malalignment. The TT-PCL describes pure lateralization of the tibial tubercle, and may be used in conjunction with the TT-TG to better understand the path taken by the extensor mechanism of the knee joint.SummaryThe TT-TG measurement is superior to the TT-PCL measurement for differentiating patients with patellofemoral instability from their stable counterparts, though TT-PCL may be useful in conjunction with TT-TG for better understanding the path of the extensor mechanism across the knee joint.

MPFL in First-Time Dislocators

Purpose of ReviewHistorically, the standard of care for patients with an acute patella dislocation has been non-operative with the exception being those with a loose body or osteochondral fracture requiring fixation or removal.Recent FindingsRecent literature has brought into question this standard of care approach and defined a higher risk subset of first-time dislocators who may benefit from early operative treatment. In addition, these studies suggest that operative treatment not only reduces the risk of recurrence but may improve outcomes overall and specifically in the pediatric population.SummaryThough the “high risk” population of first-time dislocators has been more clearly defined, how we treat them remains controversial. We continue to need more evidence-based guidelines to help us manage who we should be fixing and how we should be fixing them. We currently have several multi-center studies in progress, including one specifically looking at the question of medial patellofemoral ligament reconstruction in first-time pediatric and adolescent dislocators.