Anikar Chhabra

Accuracy of the lever sign test in the diagnosis of anterior cruciate ligament injuries

Background: The lever sign test is a new physical examination tool to diagnose anterior cruciate ligament (ACL) tears. Preliminary results suggest almost 100% sensitivity and specificity to diagnose acute and chronic complete ACL tears and clinically significant partial tears as compared with magnetic resonance imaging (MRI). Purpose: To assess the sensitivity and specificity of the lever sign test for the diagnosis of acute ACL injuries, as compared to MRI. We also aimed to determine the accuracy of the lever sign test compared with 3 other tests (anterior drawer, Lachman, and pivot shift) when performed by providers of various training levels, and with the patient awake or under anesthesia. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: We evaluated patients with a chief concern of acute (≤4 weeks) knee pain seen between October 2014 and January 2015, with a thorough history, physical examination, and standard radiographs. MRI was the reference standard; patients without an MRI evaluation were excluded. The 4 physical examination maneuvers were performed on each symptomatic knee during the initial clinic visit (for nonsurgical patients) or under anesthesia in the operating room (for surgical patients) by a randomly assigned undergraduate student, medical student, orthopaedic resident, or orthopaedic fellow. The senior author trained all staff to perform the lever sign test. Statistical analyses were performed. Results: Of 102 patients, 54 were surgical (28 female, 26 male), and 48 were nonsurgical (16 female, 32 male); the mean patient age was 23 years (range, 15-66 years). The overall accuracy of the lever sign test was 77% (63% sensitivity, 90% specificity); the accuracy was similar between patients under anesthesia and awake (77% vs 76%, respectively). There were no significant differences when comparing the sensitivity and specificity of the lever sign test with patients under anesthesia and awake (sensitivity: under anesthesia, 86%, and awake, 68% [P = .40]; specificity: under anesthesia, 85%, and awake, 96% [P = .17]). Furthermore, the accuracy of the lever sign test was similar when performed on female versus male patients (75% vs 79%, respectively) or when performed by undergraduate students and medical students compared with orthopaedic residents and fellows (84% vs 88%, respectively). Conclusion: Our study results challenge the exceptional sensitivity and specificity values (both 100%) of the lever sign test, as reported by the original author of the test.

Identification of the Anterolateral Ligament on Magnetic Resonance Imaging

Studies continue to demonstrate the importance of the anterolateral ligament (ALL) as a secondary restraint in rotational stability of the knee. No clinical exam exists to reliably test the ALL. Advanced imaging allows the surgeon to reliably identify the ALL as an independent structure of the lateral knee. This technique paper provides a reproducible method for identification of the ALL on 3T magnetic resonance imaging based on previously conducted cadaveric dissections of the ligament.

Shoulder injuries in National Collegiate Athletic Association quarterbacks: 10-year epidemiology of incidence, risk factors, and trends

Background: Up to 50% of National Collegiate Athletic Association (NCAA) football players have a history of shoulder injuries. The quarterback position has been shown to have a high prevalence of these injuries because of its unique exposures. There is little information regarding the shoulder injury type and mechanism in NCAA quarterbacks. Purpose: To understand the 10-year epidemiology of specific shoulder injury rates in NCAA quarterbacks. Study Design: Descriptive epidemiology study. Methods: Shoulder injury data for collegiate football quarterbacks from the 2004 through 2014 academic years were analyzed using the NCAA Injury Surveillance Program (ISP) data set. Results: Over the 10-year study period, a total of 133 shoulder injuries to collegiate quarterbacks were reported, with 157,288 quarterback exposures. There was approximately 1 shoulder injury per 1221 exposures. The most common injuries noted were acromioclavicular sprains (45.1%, n = 60), followed by shoulder contusions (9.0%, n = 12), clavicular fractures (7.5%, n = 10), and anterior instability (5.3%, n = 7). The majority of injuries were caused by contact with a player (60.2%, n = 80) or contact with a playing surface (28.6%, n = 38), and 88% (n = 117) were deemed nonsurgical in nature. Conclusion: NCAA ISP data analysis suggests that collegiate quarterbacks sustain acute contact injuries 89% of the time and that they typically occur while being tackled, resulting in a time loss of less than 2 weeks. These injuries are commonly treated nonsurgically.

Medial Patellofemoral Ligament Reconstruction Using All-Soft Suture Anchors for Patellar Fixation

The medial patellofemoral ligament (MPFL), which is critical for both patellar stability and normal kinematics of the patellofemoral joint, is disrupted in most patellar dislocations. Consequently, MPFL reconstruction is advocated in recurrent dislocations to restore native patellar constraints. Fixation of the MPFL graft to the medial border of the patella can be achieved through various methods, each with its own benefits and drawbacks. We present a technique for MPFL fixation to the patella using all-soft suture anchors, theoretically decreasing the risk of patellar fracture and articular surface violation.

Does Greater Trochanter Decortication Affect Suture Anchor Pullout Strength in Abductor Tendon Repairs? A Biomechanical Study:

Background: Greater trochanter decortication is frequently performed at the time of abductor tendon repair to theoretically increase healing potential. No previous studies have determined the effect that greater trochanter decortication has on the pullout strength of suture anchors. Hypothesis/Purpose: The purpose of this study is to determine whether greater trochanter decortication and bone mineral density affect suture anchor pullout strength in abductor tendon repair. The authors hypothesize that both will have a significant detrimental effect on suture anchor pullout strength. Study Design: Controlled laboratory study. Methods: Nineteen cadaveric proximal femurs with accompanying demographic data and computed tomography scans were skeletonized to expose the greater trochanter. Bone density measurements were acquired by converting Hounsfield units to T-score, based on a standardized volumetric sample in the intertrochanteric region of the femur. The gluteus medius insertion site on the lateral facet of the greater trochanter was evenly divided into 2 regions, anterior-distal and posterior-proximal, and each region was randomly assigned to receive either no decortication or 2 mm of bone decortication. A single biocomposite anchor was implanted in each region and initially tested with cyclic loading for 10 cycles at 0-50 N, 0-100 N, 0-150 N, and 0-200 N, followed by load to failure (LTF) tested at 1 mm/s. For each trial, the number of cycles endured, LTF, mechanism of failure, and stiffness were recorded. Results: Greater trochanters with no decortication and 2 mm of decortication survived a mean ± SD 35.1 ± 6.4 and 28.5 ± 10.6 cycles, respectively (P < .01). Load to failure for nondecorticated specimens was 206.7 ± 75.0 N versus 152.3 ± 60.2 N for decorticated specimens (P < .001). In a multivariate analysis, decortication and bone density were determinants in LTF (P < .05). Conclusion: Decortication and decreased bone mineral density significantly decreased the pullout strength of suture anchors in the lateral facet of the greater trochanter. Clinical Relevance: Bone density should be considered when determining whether to perform greater trochanter decortication in abductor tendon repairs.

Anterior Cruciate Ligament Tunnel Placement Using the Pathfinder Guide

Reconstruction techniques for the anterior cruciate ligament (ACL) have evolved considerably over the past 3 decades. The femoral tunnel is most commonly made via a transtibial or separate anteromedial portal approach. Benefits and drawbacks for each of these techniques exist. Improper tunnel placement is the cause of failure for ACL reconstruction 70% of the time. We present a hybrid technique for femoral tunnel placement using the Pathfinder ACL guide, which attempts to give the surgeon many of the benefits of both the transtibial and anteromedial portal techniques without the drawbacks.

Lesser Trochanter Osteoplasty for Ischiofemoral Impingement

Ischiofemoral impingement is a newly recognized cause of extra-articular hip pain, and is caused by contact between the lesser trochanter and ischium. Surgical intervention has been proven successful for patients with persistent pain and disability after failure of nonoperative management. This technique article provides a reliable method for endoscopic lesser trochanter osteoplasty using an anterior approach.

Arthroscopic Iliopsoas Release at the Level of the Lesser Trochanter Following Total Hip Arthroplasty

Iliopsoas impingement is an uncommon cause of pain after total hip arthroplasty. If pain persists after a trial of conservative treatment, surgical intervention can alleviate the patients symptoms. Multiple advantages exist to release the iliopsoas tendon at the level of the lesser trochanter. The purpose of this Technical Note is to demonstrate a technique for arthroscopic release of the iliopsoas tendon at the lesser trochanter after total hip arthroplasty.

Diagnostic Evaluation of the Knee in the Office Setting Using Small-Bore Needle Arthroscopy

Arthroscopy is currently the gold standard for diagnosing intra-articular knee pathology. Magnetic resonance imaging (MRI) can be a clinical adjunct for diagnosis; however, it is not without its shortcomings. Although highly accurate, even advanced imaging misdiagnoses the condition in 1 in 14 patients with regard to anterior cruciate ligament pathology. Previous studies have indicated that MRI fails to identify meniscal pathology when one exists in 1 of every 10 cases, and diagnoses pathology when pathology truly does not exist in 1 of every 5 patients. In-office arthroscopy offers an alternative to formal diagnostic arthroscopy, with reduced cost and risk of complications. This is a technique article that discusses the use of small-bore needle arthroscopy in the office setting.