Faculty Bibliography

INTRODUCTION: Recurrent patellar instability can be a source of continued pain and functional limitation in the young, active patient population. Instability in the setting of an elevated tibial tubercle-trochlear groove (TT-TG) distance can be effectively managed with a tibial tubercle osteotomy. At the present time, clinical outcome data are limited with respect to this surgical approach to patellar instability. METHODS: A retrospective chart review was performed to identify all cases of tibial tubercle osteotomy for the management of patellar instability performed at our institution with at least 1 year of post-operative follow-up. Patient demographic information was collected along with relevant operative data. Each patient was evaluated post-operatively with their outcomes assessed utilising a visual analogue score of pain, patient satisfaction, Tegner Activity Scale and Kujala score. RESULTS: 31 patients (23 females and 8 males) with mean age of 27 years (17-43 years) and a mean BMI of 26.3kg/m(2) (19.6-35.8) at time of surgery who underwent a tibial tubercle osteotomy as treatment for recurrent patellar instability were identified. The cohort had a mean follow up of 4.4 years (1.5-11.8 years). The mean pre-operative TT-TG distance was 18mm (10-22mm). The mean VAS pain score demonstrated a significant improvement from 6.8 (95% CI 6.1-7.5) at baseline to 2.8 (95% CI 1.9-3.7) post-operatively (p<0.001). The Tegner score improved from 4.1 (95% CI 3.4-4.8) pre-operatively to 5.2 (95% CI 4.5-5.9) at the time of final follow up (p<0.04). The Kujala score for anterior knee pain improved postoperatively from 62 (95% CI 55.4-68.7) to 76.5 (95% CI 69.5-83.5) at final follow up (p<0.001). 26 of the 31 patients (83.8%) had good to excellent Kujala scores. 27 of 31 patients (87.1%) reported that they would undergo the procedure again if necessary. CONCLUSION: For the management of recurrent patellar instability in the setting of an increased tibial tubercle-trochlear groove distance, a corrective tibial tubercle osteotomy is an effective treatment modality to reliably prevent patellar instability while reducing pain and improving function in this cohort of young, active patients.

Bone marrow edema of the knee occurs secondary to a myriad of causes. The hallmark of a bone marrow lesion (BML) is an area of decreased signal intensity on T1 weighted MRI with a corresponding area of increased signal intensity on a T2 weighted MRI. Recently, chronic bone marrow lesions have been correlated with knee pain and progression of osteoarthritis. These lesions have also been associated with other degenerative conditions such as meniscal tears, cartilage deterioration, subchondral cyst formation, mechanical malalignment, and ultimately progression to arthroplasty. Medical treatments, such as prostacyclin and bisphosphonate therapy, have shown promise. Alignment procedures, as well as core decompression and subchondroplasty, have been used as surgical treatments for chronic BMLs.

Osteochondritis dissecans (OCD) of the capitellum is an articular cartilage lesion commonly affecting young adolescents. The exact mechanism for the development of these lesions is still uncertain; however, both traumatic and vascular etiologies have been described. Careful physical examination in conjunction with appropriate diagnostic studies helps the surgeon to classify these lesions as stable or unstable and leads to proper management. There is a diverse array of treatments available for OCD lesions of the capitellum, including fragment excision or fixation, bone marrow stimulation, and osteochondral autograft transplantation. This review helps the orthopaedic surgeon understand the diagnosis and management options available for OCD lesions of the capitellum.

BACKGROUND: The purpose of this study was to see if 3-dimensional (3D) magnetic resonance imaging (MRI) could improve our understanding of rotator cuff tendon tear shapes. We believed that 3D MRI would be more accurate than two-dimensional (2D) MRI for classifying tear shapes. METHODS: We performed a retrospective review of MRI studies of patients with arthroscopically proven full-thickness rotator cuff tears. Two orthopedic surgeons reviewed the information for each case, including scope images, and characterized the shape of the cuff tear into crescent, longitudinal, U- or L-shaped longitudinal, and massive type. Two musculoskeletal radiologists reviewed the corresponding MRI studies independently and blind to the arthroscopic findings and characterized the shape on the basis of the tear's retraction and size using 2D MRI. The 3D reconstructions of each cuff tear were reviewed by each radiologist to characterize the shape. Statistical analysis included 95% confidence intervals and intraclass correlation coefficients. RESULTS: The study reviewed 34 patients. The accuracy for differentiating between crescent-shaped, longitudinal, and massive tears using measurements on 2D MRI was 70.6% for reader 1 and 67.6% for reader 2. The accuracy for tear shape characterization into crescent and longitudinal U- or L-shaped using 3D MRI was 97.1% for reader 1 and 82.4% for reader 2. When further characterizing the longitudinal tears as massive or not using 3D MRI, both readers had an accuracy of 76.9% (10 of 13). The overall accuracy of 3D MRI was 82.4% (56 of 68), significantly different (P = .021) from 2D MRI accuracy (64.7%). CONCLUSION: Our study has demonstrated that 3D MR reconstructions of the rotator cuff improve the accuracy of characterizing rotator cuff tear shapes compared with current 2D MRI-based techniques.

The purpose of the current study was to determine if the application of platelet-rich fibrin matrix could improve regeneration of the tendon-bone insertion site in a rat rotator cuff repair model. 25 Lewis syngeneic rats underwent bilateral tenotomy and repair of the supraspinatus tendon. 10 separate rats were used for PRFM harvest. All left (control) shoulders underwent transosseous rotator cuff repair, while all right (treatment) shoulders were repaired similarly with PRFM augmentation. 9 rats were sacrificed at 2-weeks and ten at 4-weeks for biomechanical testing. 3 separate rats were sacrificed at 2-weeks and 4-weeks each for histologic analysis of the insertion site. At 2 weeks, the experimental group repairs were significantly stronger in ultimate load to failure (P=0.01), stress (P=0.03), and stiffness (P=0.03). Differences in biomechanical testing were not found between the groups at 4 weeks. Histological analysis revealed less collagen organization and cartilage formation at the insertion site in the experimental group. Semiquantitative histologic analysis confirmed our qualitative assessment of the specimens. PRFM does not recapitulate the native enthesis, but rather induces an exuberant and disordered healing response that is characterized by fibrovascular scar tissue.

INTRODUCTION: Though outcomes following ACL reconstruction are largely positive, patients' post-operative recovery is highly variable, and is typically based off generalized timetables derived from population data. In an attempt to individualize prognostic estimates and establish how biomarker concentrations may change with injury, we sampled knee joint synovial fluid from patients with ACL tears with and without associated cartilage injuries and compared biomarker concentrations to samples obtained from the contralateral non-injured knee. Method: In an institutional review board approved study, 480 patients indicated for knee arthroscopy were consented and had samples drawn to form a synovial fluid database. If no injury history or symptoms were present in the contralateral knee, samples were drawn as well. For the current study, only patients that had confirmed ACL injury at the time of arthroscopy were included. Associated cartilage injury location, size and depth was documented. Synovial fluid samples were centrifuged, and the concentrations of 20 biomarkers were determined using a multiplex magnetic bead immunoassay. Concentrations were then compared between the three study groups (ACL tear with cartilage injury, ACL tears without cartilage injury, and healthy contralateral knees) using a Welch ANOVA test with pairwise comparisons. Results: The study included samples from 132 knees: 34 ACL tears without cartilage injury (mean age 34.0 years); 28 ACL tears with cartilage injury (mean age 36.3 years), and 72 contralateral knees (41.1 years). ANOVA testing demonstrated significant differences among groups for: MMP-3 (p>001); TIMP-1 (p=.001); TIMP-2 (p=.015); FGF-2 (p=.011); IL-6 (p=.001); and MlP-lb (p=001). Pairwise comparisons demonstrated no significant differences between ACL tears with, and without cartilage damage, but did show both types of ACL tears had significantly higher concentrations of MMP-3, TIMP-1, IL-6, and MlP-lb than contralaterals. ACL tears without cartilage damage had significantly lower concentrations of TIMP-2 and FGF-2 (13) than contralaterals (Table 1). Discussion: The course from surgery to symptomatic relief and functional improvement following ACL reconstruction is highly variable. Data from the current study demonstrated that cytokine concentrations are significantly different between ACL tears (+/- cartilage damage) and healthy knees. SIGNIFICANCE: These validated differences can help establish synovial fluid biomarker analysis as a method for injury stratification ultimately providing patient-specific prognostic data

Preoperative planning is an essential prerequisite for the success of orthopaedic procedures. Traditionally, the exercise has involved the written down, step by step "blueprint" of the surgical procedure. Preoperative planning of the technical aspects of the orthopaedic procedure has been performed on hardcopy radiographs using various methods such as copying the radiographic image on tracing papers to practice the planned inter - ventions. This method has become less practical due to variability in radiographic magnification and increasing implementation of digital imaging systems. Advances in technology along with recognition of the importance of surgical safety protocols resulted in widespread changes in orthopaedic preoperative planning approaches. Nowa - days, perioperative "briefings" have gained particular importance and novel planning methods have started to integrate into orthopaedic practice. These methods include using software that enables surgeons to perform preoperative planning on digital radiographs and to construct 3D digital models or prototypes of various orthopaedic pathologies from a patient's CT scans to practice preoperatively. Evidence-to-date suggests that preoperative planning and briefings are effective means of favorably influencing the outcomes of orthopaedic procedures.

INTRODUCTION: Historically, venous thromboembolism (VTE) in the setting of elective knee arthroscopy has been considered rare. However, more recently, the rate of deep vein thrombosis (DVT) has been reported to be approxi - mately 10%. With increasing recognition of the potential for the development of thromboembolic events, several random - ized trials have evaluated the efficacy of chemoprophylaxis in reducing the risk of VTE following knee arthroscopy. However, all of these studies have evaluated the efficacy of low molecular weight heparins (LMWH), with reductions in the risk of DVT ranging from 65% to 93%, but with the potential side effect of bleeding. At the present time, there have been no randomized studies reported evaluating the utility of aspirin, an agent with a reportedly lower bleeding risk than LMWH, as pharmacologic prophylaxis against VTE after arthroscopic knee surgery. METHODS: In a single-center, randomized, single-blind prospective trial, the efficacy of aspirin as postopera - tive pharmacologic VTE prophylaxis was evaluated in a low risk population undergoing knee arthroscopy. One hundred seventy patients were randomized to a treatment group of 325 mg of aspirin daily for 14 days postoperatively (66 patients) or to the control group with no intervention (104 patients). Bilateral, whole leg, com - pression venous duplex ultrasonography was performed 10 to 14 days postoperatively to document the incidence of DVT. The primary endpoint of the current study was the development of DVT or pulmonary embolism (PE), and the secondary endpoint was the development of a postoperative complication. RESULTS: The study cohort was comprised of 104 males (61%) and 66 females (39%) with a mean age of 44.4 +/- 14.4 years (range: 18 to 75 years). Within both the aspirin treatment and control groups, the surgical procedures in - cluded meniscectomy, ACL reconstruction, chondroplasty, and meniscus repair. No cases of postoperative deep vein thrombosis (DVT) or pulmonary embolism (PE) were identi - fied in either arm of the study during the observation period. Twenty-three patients experienced a complication, including pain or swelling (9%), residual joint line tenderness (3%), arthrofibrosis (0.6%), and instability after a fall (0.6%). Three patients developed knee swelling, two of them in the aspirin group and one of whom required a knee aspiration. However, there was no difference in the development of complications between the two patient populations (p = 0.76, odds ratio [OR] 1.14, 95% confidence interval [CI] 0.5-2.56). CONCLUSIONS: With no cases of VTE identified in our pa - tient population, the use of aspirin in a low-risk population undergoing arthroscopic knee surgery is not warranted.

Achilles tendon pathology is common and affects athletes and nonathletes alike. The cause is multifactorial and controversial, involving biological, anatomical, and mechanical factors. A variety of conditions characterized by Achilles tendon inflammation and/or degeneration can be clinically and histologically differentiated. These include insertional Achilles tendinopathy, retrocalcaneal bursitis, Achilles paratenonitis, Achilles tendinosis, and Achilles paratenonitis with tendinosis. The mainstay of treatment for all of these diagnoses is nonoperative. There is a large body of evidence addressing treatment of acute and chronic Achilles tendon ruptures; however, controversy remains.