Faculty Bibliography

PURPOSE: The purpose of this study was to evaluate the impact of dog ear fixation with peripheral sutures on the biomechanical properties of transosseous-equivalent rotator cuff repair. METHODS: Eight matched-pairs of fresh-frozen cadaveric shoulders were dissected to create an isolated, full thickness supraspinatus tear. One shoulder in each matched pair was randomly selected for repair with a standard transosseousequivalent suture-bridge technique (TOE), and the contralateral shoulder underwent TOE repair with additional tear edge fixation (TEF). Unidirectional tensile testing was conducted to determine cyclic displacement, linear stiffness, yield load, ultimate load, and mode of failure for each specimen. RESULTS: The ultimate load and yield load were significantly higher for the TEF group (460 +/- 104 N and 455 +/- 97 N) than the TOE group (409 +/- 111 N and 356 +/- 143 N) (p = 0.020, p = 0.019, respectively). No statistical difference was noted in stiffness or displacement. Seven of eight TOE specimens versus two of eight TEF specimens failed by medial row tendon rupture, while one of eight TOE specimens versus five of eight TEF specimens failed by lateral row anchor pullout. CONCLUSIONS: The addition of peripheral tear edge fixation to transosseous-equivalent rotator cuff repair improves the initial load to failure properties of the construct. However, dog ear fixation has no significant impact on cyclical displacement or stiffness. CLINICAL RELEVANCE: Tear edge fixation with peripheral sutures should be considered to increase the initial strength of transosseous-equivalent rotator cuff repair while restoring the anatomic footprint. The addition of dog ear fixation may promote healing and minimize the risk of construct failure during the immediate postoperative period.

OBJECTIVE: The purpose of this study was to determine whether the simultaneous MRI evaluation of Hill-Sachs lesions and glenoid bone loss by use of the on-track off-track method can be used to predict engagement during arthroscopy. MATERIALS AND METHODS: The records of 75 consecutively registered patients (60 male patients, 15 female patients) with a history of previous anterior shoulder instability who underwent preoperative MRI of the shoulder and arthroscopy at our institution were reviewed. A total of 76 MRI examinations were included. Two readers reviewed the MR images of each patient blindly and independently and used the on-track off-track method to predict engagement. These results were compared with the findings related to engagement seen during arthroscopy, which was performed by one of seven orthopedic surgeons. Statistical analyses included Fisher exact test, logistic regression, ROC analysis, and calculation of intraclass correlation coefficients. RESULTS: Using the on-track off-track technique of reading MR images, the reviewers correctly predicted 13 of the 18 engaging (off-track) lesions (sensitivity, 72.2%). Among the 58 shoulders that did not engage (on-track), they correctly predicted 51 (specificity, 87.9%). Overall, the accuracy of the on-track off-track method was 84.2% with a positive predictive value of 65.0% and negative predictive value of 91.1%. CONCLUSION: Our study showed that the on-track off-track method can be used in MRI to accurately assess the bipolar bone loss seen in patients with anterior shoulder instability for predicting the presence of engaging, or off-track, lesions. This information can be used preoperatively to help guide the type of stabilization procedure performed on patients with anterior shoulder instability.

PURPOSE: To explore the feasibility of T1rho mapping of menisci at 3T in discriminating between patients with acute anterior cruciate ligament (ACL) injury and healthy controls. MATERIALS AND METHODS: Thirty-three subjects were included in the study and subdivided into two subgroups: 16 healthy controls (4 females, 12 males; mean age = 34.4 +/- 10.2 years, age range 24-63 years), 17 patients with ACL injury (3 females, 14 males; mean age = 29.8 +/- 10.8 years, age range 18-61 years). T1rho images from all subjects were acquired on a 3T MR scanner using a spin-lock-based 3D GRE sequence and computed for T1rho mapping. Clinical proton density (PD)-weighted fast spin echo (FSE) images in the sagittal (without fat saturation), axial, and coronal (fat-saturated) planes were also acquired for cartilage assessment using Whole-Organ MR Imaging Score (WORMS) grading. Mixed model two-way analysis of variance (ANOVA) was performed to determine whether there were any significant differences among subregional, compartmental, and whole structure T1rho values of meniscus between healthy controls and ACL-injured patients. RESULTS: Lateral posterior (29 +/- 8 msec) and medial central (25 +/- 7 msec) meniscus subregions in healthy controls had significantly lower T1rho values (P < 0.05) than the corresponding meniscus subregions in ACL-injured patients. Significantly lower meniscus T1rho values (P < 0.05) were also identified in lateral compartment in healthy controls (26 +/- 6 msec) than that of ACL-injured patients (33 +/- 4 msec). Subjects' total WORMS between healthy controls and ACL-injured patients had significant differences (P < 0.05). CONCLUSIONS: These preliminary results indicate that T1rho mapping is possibly feasible in detecting meniscus degeneration and may be useful in distinguishing ACL-injured patients. J. Magn. Reson. Imaging 2014. (c) 2014 Wiley Periodicals, Inc.

The glenohumeral joint is innately complex and comprised of both static and dynamic stabilizers. Anterior glenohumeral instability has been estimated to have an incidence of 11.2 cases per 100,000 persons and typically follows a traumatic injury. Although there are specific instances when conservative management is advocated, a majority of these patients are treated with operative stabilization. Recent advancements in arthroscopy have created a shift from the traditional open stabilization procedures towards more minimally invasive arthroscopic stabilization procedures. This comprehensive review will summarize current concepts involved in evaluating patients with anterior glenohumeral instability and specifically focus on those patients who suffer from recurrent instability.

RATIONALE AND OBJECTIVES: The objectives of this study were to investigate the changes in compartment-specific subchondral bone marrow lipids of femoral-tibial bone in acute anterior cruciate ligament (ACL)-injured patients compared to that of healthy volunteers and patients with osteoarthritis (OA) (Kellgren-Lawrence [KL] grade 2-3). MATERIALS AND METHODS: A total of 55 subjects were recruited in the study and subdivided into three subgroups: 17 healthy controls (4 females, 13 males; mean age = 41 +/- 16, age range 24-78 years), 17 patients with acute ACL injury (3 females, 14 males; mean age = 30 +/- 11, age range 18-61 years), and 21 patients with KL2-3 OA (12 females, 9 males; mean age = 65 +/- 12, age range 44-89 years). Routine clinical proton density-weighted fast spin echo images in sagittal (without fat saturation), axial, and coronal (fat saturation) planes were acquired on a 3 T clinical scanner for cartilage morphology using Whole-Organ Magnetic Resonance Imaging Score grading. A voxel of 10 x 10 x 10 mm3 was positioned in the medial and lateral compartments of the tibia and femur for proton magnetic resonance spectroscopy measurements using the single voxel stimulated echo acquisition mode pulse sequence. All proton magnetic resonance data were processed with Java-based magnetic resonance user interface. Wilcoxon rank sum test and mixed model two-way analysis of variance were performed to determine significant differences between different compartments and examine the effect of ACL injury, OA grade and compartment, and their interactions. RESULTS: The index of unsaturation in lateral tibial compartment in ACL-injured patients was significantly higher (P < .05) than all compartments except lateral femoral in patients with KL2-3 OA. Significantly lower values (P < .05) were also identified in saturated lipids at 2.03 ppm in all compartments in ACL-injured patients than those of all compartments in patients with KL2-3 OA. CONCLUSIONS: The preliminary results suggest that the indices of unsaturation in the lateral tibial compartment and the peaks of saturated lipids at 1.3 and 2.03 ppm in medial tibial compartment may be clinically useful to characterize subchondral bone marrow among healthy controls, acute ACL-injured patients, and patients with OA.

BACKGROUND: Rotator cuff repairs (RCRs) have become increasingly common. Several studies have shown variation in the indications for this procedure. We chose to track the incidence of RCRs in New York State (NYS) from 1995 to 2009. We hypothesized that after the introduction of the Current Procedural Terminology (CPT) code 29827 for arthroscopic RCR, there would be a significant increase in the rate of RCRs performed in NYS. MATERIALS AND METHODS: The NYS Department of Health's Statewide Planning and Research Cooperative System (SPARCS) database was queried for reported RCRs between the years 1995 and 2009. Using the International Classification of Diseases, Ninth Revision, Clinical Modification procedural code 83.63 and CPT codes 23410, 23412, 23420, and 29827, we collected and analyzed data on RCR procedures. RESULTS: A total of 168,780 RCRs were performed in NYS from 1995 to 2009. In 1995, the population incidence of RCRs was 23.5 per 100,000. In comparison, in 2009, the population incidence was 83.1 per 100,000, an increase of 238% (P < .0001). The percentage of individuals aged between 45 and 65 years undergoing RCR increased from 53.0% to 64.2% during this same period. CONCLUSIONS: There has been a notable increase in the volume of RCRs performed in NYS. In addition, after the introduction of CPT code 29827 in 2003, the increase in the incidence of RCRs became significantly more pronounced.

Background: Allografts offer potential advantages over autografts in anterior cruciate ligament reconstruction (ACLR), including the absence of donor site morbidity, shorter operative times, improved cosmesis, and easier rehabilitation. There is limited and conflicting outcome data for ACLR with tibialis anterior allograft. The purpose of this study was to evaluate the functional outcomes of ACLR with tibialis anterior allograft. Methods:We retrospectively evaluated primary ACL reconstructions using tibialis anterior allograft between January 2004 and December 2006. Clinical outcomes were measured by KT-1000 arthrometry, and International Knee Documentation Committee (IKDC), Lysholm, and Tegner scores. Results: 19 patients were available for follow-up at a mean of 2.7 years (range: 2.0 to 3.2). One patient experienced a traumatic re-rupture that required revision and another patient was advised to undergo revision reconstruction for a failed graft. Based on IKDC and Lysholm scoring, 12 patients (63%) had good or excellent results, 4 (21%) patients had fair results, and 3 (16%) patients had poor results. The mean side-to-side difference was 2.7mm (0 to 8.2) and the mean decrease in Tegner activity level was 1.4 (0 to 6). Conclusion:An alarming number of patients demonstrated residual laxity after ACL reconstruction with tibialis anterior allograft. We recommend against using tibialis anterior allograft as a first choice graft for high demand patients.