Michael J. Alaia

Advances in magnetic resonance imaging of articular cartilage.

Abstract The pathology, assessment, and management of articular cartilage lesions of the hip and knee have been the subject of considerable attention in the recent orthopaedic literature. MRI has long been an important tool in the diagnosis and management of articular cartilage pathology, but detecting and interpreting early cartilaginous degeneration with this technology has been difficult. Biochemical‐based MRI has been advocated to detect early cartilaginous degenerative changes and assess cartilage repair. Techniques such as T2 mapping, T1rho (ie, T1 in the rotating frame), sodium MRI, and delayed gadolinium‐enhanced MRI of cartilage (dGEMRIC) take advantage of changes in the complex biochemical composition of articular cartilage and may help detect morphologic cartilaginous changes earlier than does conventional MRI. Although the newer modalities have been used primarily in the research setting, their ability to assess the microstructure of articular cartilage may eventually enhance the diagnosis and management of osteoarthritis.

Contralateral Deep Venous Thrombosis After Hip Arthroscopy

Since the 1980s, hip arthroscopy has become an accepted treatment modality for a variety of hip conditions. It is generally considered a low-risk procedure with a low rate of complications. The risk of developing a deep venous thrombosis (DVT) or venous thromboembolism following these procedures is also thought to be low, and most patients undergoing these procedures receive no pharmacologic prophylaxis postoperatively. This article presents a case of a 33-year-old woman with a history of oral contraceptive use who presented 13 days after a routine hip arthroscopy with pain and swelling in the contralateral thigh. Ultrasonography revealed acute DVTs in the left common femoral, superficial femoral, and popliteal veins. She was admitted to the hospital and treated accordingly. A workup for thrombophilic disorders was negative. We believe that her history of oral contraceptive use, the use of axial traction, and asymmetric forces about the pelvis during the procedure contributed to this postoperative complication. Although this complication is rare and the use of pharmacologic prophylaxis is not common, physicians must be aware of this potential complication following hip arthroscopy.

Using “Near Misses” Analysis to Prevent Wrong-Site Surgery

Summary:The purpose of our pre–post intervention study was to reduce the number of near‐miss events pertaining to wrong‐site surgery, including incorrectly sided surgical bookings and incorrectly performed preoperative time‐out procedures. Pre‐ and postintervention, incorrectly booked cases, and improperly performed presurgical time‐out procedures were recorded. We then educated each surgeon and their staff regarding the importance of and proper way to perform these tasks. Subsequently, the monthly percentage of incorrectly booked surgical procedures and improperly performed time‐outs were significantly decreased. Introduction:In 2004, the Joint Commission published comprehensive guidelines to prevent wrong‐site surgery. Seven years have passed, and the incidence has not declined. The Joint Commission estimates that in the United States, wrong‐site procedures including surgeries occur at least 40 times a week. “Near misses” are events that could have harmed a patient, but did not due to chance or mitigation. Improperly performed time‐out procedures and inaccurate surgical bookings are considered near misses and could ultimately lead to “never events,” such as wrong‐site surgery. Near‐miss analysis is a highly effective method of preventing rare, “never events.” We hypothesize that proper education of surgeons and staff will be effective in reducing the number of near misses. Methods:All cases analyzed were performed at an academic, orthopedic surgery specialty institution. From August 2010 to May 2011, near misses were identified and stored in Patient Safety Net (PSN), an electronic database. We tracked these cases and educated each offending attending physician and his or her staff about the importance of accurate surgical bookings. Additionally, we began an observational program to carefully review presurgical time‐out procedures as they occurred. We tracked the percentage of these improperly performed time‐outs and counseled offenders (attending surgeon, or any member of the operating room staff who made the error) regarding the deficiencies that caused the time‐out to be ineffective. The number of near misses that occurred before and after the interventions were recorded and analyzed. Results:Of the 12,215 cases included in this study, 6,126 cases formulated the “pre‐education” cohort, while a total of 6,089 cases formulated the “post‐education” cohort. In the first four months of the study, the monthly rate of incorrectly booked cases was 0.75%. Since the intervention, the rate decreased to 0.41% (p = .0139). The percentage of improperly performed time‐out procedures decreased from 18.7% to 5.9% after the educational interventions were performed (p < .0001). Conclusion:A program designed to educate physicians to the importance of decreasing near misses for wrong‐site surgery is effective. When analyzing the literature, it is clear that the reduction in near misses observed in this study decreases the likelihood of a wrong‐site surgery.

Catastrophic Failure of a Metal-on-Metal Total Hip Arthroplasty Secondary to Metal Inlay Dissociation

Metal-on-metal bearing surfaces in total hip arthroplasty have been recently shown to have acceptable survivorship properties (J Bone Joint Surg Am. 2006;88:1183; J Bone Joint Surg Am. 2006;88:1173), and they have certain advantages and disadvantages when compared to conventional metal-on-polyethylene bearing surfaces. Like traditional metal-on-polyethylene bearings, these metal-on-metal implants may also suffer from catastrophic failure. This case report represents an unusual situation in a 57-year-old man in which dissociation of a metal inlay in a metal-on-metal total hip arthroplasty resulted in articulation of the inferior aspect of the inlay with the femoral neck, leading to femoral neck notching, extensive periprosthetic soft tissue metallosis, osteolysis, and subsequent prosthetic catastrophic failure.

Restoring Isometry in Lateral Ulnar Collateral Ligament Reconstruction.

PURPOSE To ascertain whether placing the humeral attachment of the lateral ulnar collateral ligament (LUCL) at the humeral center of rotation (hCOR) on the humerus would provide the most isometric reconstruction. METHODS We analyzed 13 cadaver limbs from mid-humerus to the hand. The morphology of the ligament complex was assessed. The hCOR was then found using radiographic parameters. We chose 7 points on the humerus located at and around the hCOR and 3 points paralleling the supinator crest of the ulna and then calculated distances from these points using a digital caliper at 0°, 30°, 60°, 90°, and 130° flexion. Differences in potential ligamentous lengths (termed graft elongation) were then calculated and statistical analysis was performed. RESULTS There was no perfectly isometric point along the humerus or ulna. However, in all specimens the hCOR was the most isometric point for the humeral reconstruction site, with an average graft elongation of 1.1 mm. Differences in humeral tunnel position dramatically affected graft elongation at all 3 ulnar insertions. Overall, ulnar position had a minimal effect on graft elongation. CONCLUSIONS Although no perfectly isometric points were found, the humeral center of rotation consistently reproduced the most isometry when assessing graft elongation over range of motion. These data may assist surgeons in proper tunnel placement in LUCL reconstruction. CLINICAL RELEVANCE In LUCL reconstruction, the humeral tunnel should be placed as close as possible to the center of rotation, whereas placement on the ulna is less critical.

Calculating the Position of the Joint Line of the Knee Using Anatomical Landmarks

Restoration of the joint line of the knee during primary and revision total knee arthroplasty is a step that directly influences patient outcomes. In revision total knee arthroplasty, necessary bony landmarks may be missing or obscured, so there remains a lack of consensus on how to accurately identify and restore the joint line of the knee. In this study, 50 magnetic resonance images of normal knees were analyzed to determine a quantitative relationship between the joint line of the knee and 6 bony landmarks: medial and lateral femoral epicondyles, medial and lateral femoral metaphyseal flares, tibial tubercle, and proximal tibio-fibular joint. Wide variability was found in the absolute distance from each landmark to the joint line of the knee, including significant differences between the sexes. Normalization of the absolute distances to femoral or tibial diameters revealed reliable spatial relationships to the joint line of the knee. The joint line was found to be equidistant from the lateral femoral epicondyle and the proximal tibio-fibular joint, representing a reproducible point of reference for joint line restoration. The authors propose a simple 3-step algorithm that can be used with magnetic resonance imaging, computed tomography, or radiography to reliably determine the anatomical location of the joint line of the knee relative to the surrounding bony anatomy. [Orthopedics. 2016; 39(6):381-386.].

Does Anteromedial Portal Drilling Improve Footprint Placement in Anterior Cruciate Ligament Reconstruction

BackgroundConsiderable debate remains over which anterior cruciate ligament (ACL) reconstruction technique can best restore knee stability. Traditionally, femoral tunnel drilling has been done through a previously drilled tibial tunnel; however, potential nonanatomic tunnel placement can produce a vertical graft, which although it would restore sagittal stability, it would not control rotational stability. To address this, some suggest that the femoral tunnel be created independently of the tibial tunnel through the use of an anteromedial (AM) portal, but whether this results in a more anatomic footprint or in stability comparable to that of the intact contralateral knee still remains controversial.Questions/purposes(1) Does the AM technique achieve footprints closer to anatomic than the transtibial (TT) technique? (2) Does the AM technique result in stability equivalent to that of the intact contralateral knee? (3) Are there differences in patient-reported outcomes between the two techniques?MethodsTwenty male patients who underwent a bone-patellar tendon-bone autograft were recruited for this study, 10 in the TT group and 10 in the AM group. Patients in each group were randomly selected from four surgeons at our institution with both groups demonstrating similar demographics. The type of procedure chosen for each patient was based on the preferred technique of the surgeon. Some surgeons exclusively used the TT technique, whereas other surgeons specifically used the AM technique. Surgeons had no input on which patients were chosen to participate in this study. Mean postoperative time was 13 ± 2.8 and 15 ± 3.2 months for the TT and AM groups, respectively. Patients were identified retrospectively as having either the TT or AM Technique from our institutional database. At followup, clinical outcome scores were gathered as well as the footprint placement and knee stability assessed. To assess the footprint placement and knee stability, three-dimensional surface models of the femur, tibia, and ACL were created from MRI scans. The femoral and tibial footprints of the ACL reconstruction as compared with the intact contralateral ACL were determined. In addition, the AP displacement and rotational displacement of the femur were determined. Lastly, as a secondary measurement of stability, KT-1000 measurements were obtained at the followup visit. An a priori sample size calculation indicated that with 2n = 20 patients, we could detect a difference of 1 mm with 80% power at p < 0.05. A Welch two-sample t-test (p < 0.05) was performed to determine differences in the footprint measurements, AP displacement, rotational displacement, and KT-1000 measurements between the TT and AM groups. We further used the confidence interval approach with 90% confidence intervals on the pairwise mean group differences using a Games-Howell post hoc test to assess equivalence between the TT and AM groups for the previously mentioned measures.ResultsThe AM and TT techniques were the same in terms of footprint except in the distal-proximal location of the femur. The TT for the femoral footprint (DP%D) was 9% ± 6%, whereas the AM was −1% ± 13% (p = 0.04). The TT technique resulted in a more proximal footprint and therefore a more vertical graft compared with intact ACL. The AP displacement and rotation between groups were the same and clinical outcomes did not demonstrate a difference.ConclusionsAlthough the AM portal drilling may place the femoral footprint in a more anatomic position, clinical stability and outcomes may be similar as long as attempts are made at creating an anatomic position of the graft.Level of EvidenceLevel III, therapeutic study.

Primary anterior cruciate ligament reconstruction: perioperative considerations and complications

ABSTRACT Anterior cruciate ligament (ACL) injuries are among the most commonly studied orthopaedic injuries. Despite having an excellent prognosis, complications do occur. The timely recognition and management of complications is imperative to ensure the success of reconstruction. Avoiding such complications requires thorough preoperative planning, proficient technical skills to properly manage intraoperative complications, and an extensive knowledge of possible postoperative complications.

Transosseous-Equivalent Repair for Distal Patellar Tendon Avulsion

Extensor mechanism disruptions are relatively uncommon injuries involving injury to the quadriceps tendon, patella, or patellar tendon. Patellar tendon avulsions from the tibial tubercle in adults are rare; as such, little technical information has been written regarding surgical management of this injury in the adult. Transosseous-equivalent repairs have been described in the management of several types of tendon ruptures, including rotator cuff and distal triceps tendon ruptures, but not previously in patellar injuries. We present a technique for repairing an avulsion injury of the patellar tendon from the tibial tubercle using suture anchors in a transosseous-equivalent manner. This technique for treating distal patellar tendon avulsion injuries likely increases contact area at the repair site while potentially improving fixation strength.

Pasteurella multocida infection in a primary shoulder arthroplasty after cat scratch: case report and review of literature

Infected joint arthroplasty presents a significant challenge to orthopedic surgeons. Common causative organisms include Staphylococcus aureus (22%-39%), coagulase-negative staphylococci (15%-37.5%), gramnegative bacilli (4%-28.2%), streptococci (6%-11.2%), enterococci (0%-9.2%), and anaerobes (0%-6.5%). 10 Occasionally, equally in immunocompromised individuals, infection can be caused by uncommon organisms. Pasteurella multocida is a rare causal organism of infected joint replacement that has only previously been reported in cases of knee and hip arthroplasties. 8,12,18,19 We present an unusual case of an infected shoulder arthroplasty caused by Pasteurella multocida after a cat scratch.