The Albright-Losee Low Profile Pivot Shift Test for ACL Deficiency.

Background: Recognizing ACL injuries on the field and in the office can be very challenging in awake and apprehensive patients. Despite high specificity, many published "pivot-shift" techniques have limited acceptance mainly because of unsatisfactory sensitivity. We describe in detail, four specific modifications and provide a critical review of our clinical experiences to empower the new user's readiness to master a novel screening procedure for ACL disruption.

Meniscal and Articular Cartilage Predictors of Outcome After Revision ACL Reconstruction: A 6-Year Follow-up Cohort Study.

Background: Meniscal and chondral damage is common in the patient undergoing revision anterior cruciate ligament (ACL) reconstruction.

Purpose: To determine if meniscal and/or articular cartilage pathology at the time of revision ACL surgery significantly influences a patient's outcome at 6-year follow-up.

Study Design: Cohort study; Level of evidence, 3.

Stress Control of Dike Deflection and Flank Eruption at Akaroa Volcano, New Zealand.

Understanding the stress evolution of extinct volcanoes can improve efforts to forecast flank eruptions on active systems. Field, petrographic, and seismic data are combined with numerical modeling to investigate the paleo-stress field of New Zealand's Akaroa Volcano, or Akaroa Volcanic Complex. Field mapping identifies 86 radially oriented dikes and seven lava domes found only within a narrow elevation range along Akaroa's erosional crater rim.

Returning to Activity After Anterior Cruciate Ligament Revision Surgery: An Analysis of the Multicenter Anterior Cruciate Ligament Revision Study (MARS) Cohort at 2 Years Postoperative.

Background: Patients with anterior cruciate ligament (ACL) revision report lower outcome scores on validated knee questionnaires postoperatively compared to cohorts with primary ACL reconstruction. In a previously active population, it is unclear if patient-reported outcomes (PROs) are associated with a return to activity (RTA) or vary by sports participation level (higher level vs. recreational athletes).

Association Between Graft Choice and 6-Year Outcomes of Revision Anterior Cruciate Ligament Reconstruction in the MARS Cohort.

Background: Although graft choice may be limited in the revision setting based on previously used grafts, most surgeons believe that graft choice for anterior cruciate ligament (ACL) reconstruction is an important factor related to outcome.

Hypothesis: In the ACL revision setting, there would be no difference between autograft and allograft in rerupture rate and patient-reported outcomes (PROs) at 6-year follow-up.

Study Design: Cohort study; Level of evidence, 2.

Rate of infection following revision anterior cruciate ligament reconstruction and associated patient- and surgeon-dependent risk factors: Retrospective results from MOON and MARS data collected from 2002 to 2011.

Infection is a rare occurrence after revision anterior cruciate ligament reconstruction (rACLR). Because of the low rates of infection, it has been difficult to identify risk factors for infection in this patient population. The purpose of this study was to report the rate of infection following rACLR and assess whether infection is associated with patient- and surgeon-dependent risk factors.

Meniscal Repair in the Setting of Revision Anterior Cruciate Ligament Reconstruction: Results From the MARS Cohort.

Background: Meniscal preservation has been demonstrated to contribute to long-term knee health. This has been a successful intervention in patients with isolated tears and tears associated with anterior cruciate ligament (ACL) reconstruction. However, the results of meniscal repair in the setting of revision ACL reconstruction have not been documented.

Association of chemokine expression in anterior cruciate ligament deficient knee with patient characteristics: Implications for post-traumatic osteoarthritis.

Background: Stromal cell-derived factor-1a (SDF-1α) and high mobility group box chromosomal protein 1 (HMGB1) are chemokines that can drive post-traumatic osteoarthritis (PTOA) induced by anterior cruciate ligament (ACL) injury. However, the influence of patient characteristics on expression of those chemokines remains unclear. Our aim was to determine the relationship between chemokine expression in synovial fluid (SF) of the ACL-deficient (ACL-D) knee and patient characteristics including time from injury, sex, and age.

Predictors of Patient-Reported Outcomes at 2 Years After Revision Anterior Cruciate Ligament Reconstruction.

Background: Patient-reported outcomes (PROs) are a valid measure of results after revision anterior cruciate ligament (ACL) reconstruction. Revision ACL reconstruction has been documented to have worse outcomes when compared with primary ACL reconstruction. Understanding positive and negative predictors of PROs will allow surgeons to modify and potentially improve outcome for patients.

Relationship Between Sports Participation After Revision Anterior Cruciate Ligament Reconstruction and 2-Year Patient-Reported Outcome Measures.

Background: Anterior cruciate ligament (ACL) revision cohorts continually report lower outcome scores on validated knee questionnaires than primary ACL cohorts at similar time points after surgery. It is unclear how these outcomes are associated with physical activity after physician clearance for return to recreational or competitive sports after ACL revision surgery.

Hypotheses: Participants who return to either multiple sports or a singular sport after revision ACL surgery will report decreased knee symptoms, increased activity level, and improved knee function as measured by validated patient-reported outcome measures (PROMs) and compared with no sports participation.

PROMIS: a valid and efficient outcomes instrument for patients with ACL tears.

Purpose: The current study compares the Patient Reported Outcomes Information System Physical Function Computer Adaptive Test (PROMIS PF CAT) to traditional knee PRO instruments in a healthy population undergoing surgery for ACL injuries with the following objectives: (1) identify and determine the strength of any correlations between the scores of PROMIS PF CAT and current knee PROs or their subscales that measure physical function; (2) evaluate PROMIS PF CAT's test burden; and (3) determine if PROMIS PF CAT has any floor or ceiling effects in this population.

Methods: Patients indicated for ACL surgery completed the Short Form-36 Physical Function (SF-36 PF), Knee Injury and Osteoarthritis Outcome Score (KOOS), Marx Knee Activity Rating Scale (Marx), the EuroQol 5-dimensions Questionnaire (EQ-5D), and PROMIS PF CAT. Correlations between PROs were defined as follows: High (≥ 0.

Physiologic Preoperative Knee Hyperextension Is a Predictor of Failure in an Anterior Cruciate Ligament Revision Cohort: A Report From the MARS Group.

Background: The occurrence of physiologic knee hyperextension (HE) in the revision anterior cruciate ligament reconstruction (ACLR) population and its effect on outcomes have yet to be reported. Hypothesis/Purpose: The prevalence of knee HE in revision ACLR and its effect on 2-year outcome were studied with the hypothesis that preoperative physiologic knee HE ≥5° is a risk factor for anterior cruciate ligament (ACL) graft rupture.

Study Design: Cohort study; Level of evidence, 2.

Risk Factors and Predictors of Significant Chondral Surface Change From Primary to Revision Anterior Cruciate Ligament Reconstruction: A MOON and MARS Cohort Study.

Background: Articular cartilage health is an important issue following anterior cruciate ligament (ACL) injury and primary ACL reconstruction. Factors present at the time of primary ACL reconstruction may influence the subsequent progression of articular cartilage damage.

Hypothesis: Larger meniscus resection at primary ACL reconstruction, increased patient age, and increased body mass index (BMI) are associated with increased odds of worsened articular cartilage damage at the time of revision ACL reconstruction.

Surgical Predictors of Clinical Outcomes After Revision Anterior Cruciate Ligament Reconstruction.

Background: Revision anterior cruciate ligament (ACL) reconstruction has been documented to have worse outcomes compared with primary ACL reconstruction.

Hypothesis: Certain factors under the control of the surgeon at the time of revision surgery can both negatively and positively affect outcomes.

Study Design: Case-control study; Level of evidence, 3.

Performance of PROMIS for Healthy Patients Undergoing Meniscal Surgery.

Background: The Patient-Reported Outcomes Measurement Information System (PROMIS) was developed as an extensive question bank with multiple health domains that could be utilized for computerized adaptive testing (CAT). In the present study, we investigated the use of the PROMIS Physical Function CAT (PROMIS PF CAT) in an otherwise healthy population scheduled to undergo surgery for meniscal injury with the hypotheses that (1) the PROMIS PF CAT would correlate strongly with patient-reported outcome instruments that measure physical function and would not correlate strongly with those that measure other health domains, (2) there would be no ceiling effects, and (3) the test burden would be significantly less than that of the traditional measures.

Methods: Patients scheduled to undergo meniscal surgery completed the PROMIS PF CAT, Knee injury and Osteoarthritis Outcome Score (KOOS), Marx Knee Activity Rating Scale, Short Form-36 (SF-36), and EuroQol-5 Dimension (EQ-5D) questionnaires.

Subsequent Surgery After Revision Anterior Cruciate Ligament Reconstruction: Rates and Risk Factors From a Multicenter Cohort.

Background: While revision anterior cruciate ligament reconstruction (ACLR) can be performed to restore knee stability and improve patient activity levels, outcomes after this surgery are reported to be inferior to those after primary ACLR. Further reoperations after revision ACLR can have an even more profound effect on patient satisfaction and outcomes. However, there is a current lack of information regarding the rate and risk factors for subsequent surgery after revision ACLR.

Comparing the accuracy of high tibial osteotomies between computer navigation and conventional methods.

Background: The accuracy of correction has been shown to be an important determinant in long-term outcomes of patients who were treated with a medial open-wedge high tibial osteotomy (HTO) who suffer from unicompartmental osteoarthritis (OA). Computer navigation systems have the potential to improve surgical precision. The purpose of this study was to compare radiographic outcomes between patients treated with a navigation system and those treated through conventional methods of assessing alignment intra-operatively.

Lateral patellofemoral ligament reconstruction to restore functional capacity in patients previously undergoing lateral retinacular release.

Aim: To study patient outcomes after surgical correction for iatrogenic patellar instability.

Methods: This retrospective study looked at 17 patients (19 knees) suffering from disabling medial patellar instability following lateral release surgery. All patients underwent lateral patellofemoral ligament (LPFL) reconstruction by a single surgeon.

Clinical Accuracy of J-Sign Measurement Compared to Magnetic Resonance Imaging.

Background: The J-sign is defined as lateral patellar translation over the anterolateral femur proximal to the trochlear groove during active leg extension. Dynamic magnetic resonance imaging (MRI) techniques allow for quantification of the J-sign using a variety of published indices. However, to date, clinical quantification of the J-sign has not been reliably described.

TT-TG vs. modified lateral patellar edge for determination of tibial tubercle transfer distance in Fulkerson osteotomy procedures.

Background: Tibial tubercle-trochlear groove (TT-TG) distance is currently used at our institution to determine tibial tubercle medialization required in Fulkerson osteotomies. If the correlation between a modified lateral patellar edge (LPE) and the transfer distance was found to be stronger than its correlation with TT-TG, it would suggest that the best measurement to use is actually modified LPE.

Methods: The electronic medical records of 32 patients who underwent Fulkerson osteotomy procedures with femoral nerve stimulation were reviewed and measured.

Functional outcomes of MPFL reconstruction vs. graft tissue placement.

Background: The medial patellofemoral ligament (MPFL) is essential for the maintenance of correct biomechanical function of the knee. Reconstruction of the MPFL is commonly used in the restoration of patellofemoral stability after traumatic lateral subluxation of the patella. Although a method to accurately determine the MPFL's insertion point has been described, it remains unclear if anatomic placement of MPFL graft tissue is essential for preservation of knee function after MPFL reconstruction.

Correlation of radiographic patellofemoral indices with tibial tubercle transfer distance in Fulkerson osteotomy procedures.

Background: A laterally tracking patella is commonly seen in patients with chronic recurrent lateral patellar dislocations. Clinical appearance of the J-sign occurs when the patella is congruent with the trochlear groove in flexion and moves over the lateral border of the femoral condyle as the lower leg reaches complete extension. A Fulkerson osteotomy procedure corrects this maltracking of the patella by medially transferring the tibial tubercle.