Faculty Bibliography

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.

BACKGROUND: Injury to subchondral bone is associated with knee pain and osteoarthritis (OA). A percutaneous calcium phosphate injection is a novel approach in which subchondral bone marrow edema lesions are percutaneously injected with calcium phosphate. In theory, calcium phosphate provides structural support while it is gradually replaced by bone. However, little clinical evidence supports the efficacy of percutaneous calcium phosphate injections. QUESTIONS/PURPOSES: We asked: (1) Does percutaneous calcium phosphate injection improve validated patient-reported outcome measures? (2) What proportion of patients experience failure of treatment (defined as a low score on the Tegner Lysholm Knee Scoring Scale)? (3) Is there a relationship between outcome and age, sex, BMI, and preoperative grade of OA? METHODS: Between September 2012 and January 2014, we treated 33 patients with percutaneous calcium phosphate injections. Twenty-five satisfied our study inclusion criteria; of those, three patients were lost to followup and 22 (88%; 13 men, nine women) with a median age of 53.5 years (range, 38-70 years) were available for retrospective chart review and telephone evaluation at a minimum of 6 months (median, 12 months; range, 6-24 months). Our general indications for this procedure were the presence of subchondral bone marrow edema lesions observed on MR images involving weightbearing regions of the knee associated with localized pain on weightbearing and palpation and failure to respond to conservative therapy (> 3 months). Patients with pain secondary to extensive nondegenerative meniscal tears with a flipped displaced component at the level of bone marrow edema lesions, or with mechanical axis deviation greater than 8 degrees were excluded. All patients had Grades III or IV chondral lesions (modified Outerbridge grading system for chondromalacia) overlying MRI-identified subchondral bone marrow edema lesions. Percutaneous calcium phosphate injection was performed on the medial tibial condyle (15 patients), the medial femoral condyle (five patients), and the lateral femoral condyle (two patients). Concomitant partial meniscectomy was performed in 18 patients. Preoperative and postoperative scores from the Knee Injury and Arthritis Outcome Score (KOOS) and the Tegner Lysholm Knee Scoring Scale were analyzed. RESULTS: For patients available for followup, the outcome scores improved after treatment. The KOOS improved from a mean of 39.5 +/- 21.8 to 71.3 +/- 23 (95% CI, 18.6-45.2; p < 0.001) and the Tegner and Lysholm score from 48 +/- 15.1 to 77.5 +/- 20.6 (95% CI, 18.8-40.2; p < 0.001). However, seven of the 22 patients had poor clinical outcomes as assessed by the Tegner Lysholm Knee Scoring Scale, whereas three had fair results, five had good results, and seven had excellent results. The postoperative Tegner Lysholm score was inversely related to the preoperative Kellgren-Lawrence OA grade (R2 = 0.292; F (1.20) = 9.645; p = 0.006). We found no relationship between outcome scores and age, sex, or BMI. CONCLUSIONS: In a study that would have been expected to present a best-case analysis (short-term followup, loss to followup of patients with potentially unsatisfactory results, and use of invasive cotreatments including arthroscopic debridements), we found that percutaneous calcium phosphate injection in patients with symptomatic bone marrow edema lesions of the knee and advanced OA yielded poor results in a concerning proportion of our patients. Based on these results, we advise against the use of percutaneous calcium phosphate injections for patients with advanced osteoarthritic changes. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Objectives: The purpose of the present study was to determine when patients recover the ability to safely operate the brakes of an automobile following a right knee anterior cruciate ligament reconstruction (ACLR). Methods: A prospective case series of 27 patients who underwent a right knee ACLR, nine with a bone patellar tendon-bone (BPTB) autograft, nine patients who had hamstring (HS) tendon autograft and nine patients who had tibialis anterior (TA) tendon allograft for their reconstructions were tested in a validated computerized driving simulator. At 7-10 days, three weeks, and six weeks post operatively, patients were evaluated with respect to their brake reaction time (BRT), brake travel time (BTT), and total braking time (TBT). Each cohort was then compared with thirty healthy volunteers with similar demographics to establish normative mean values. Results: At 7-10 days post-operatively, all patients had statistically significant differences compared to controls for BRT, BTT, and TBT, regardless of the graft used for the reconstruction. By three weeks postoperatively, those reconstructed with TA allografts demonstrated a return to normal braking parameters with no statistically significant differences compared to controls between BRT, BTT, and TBT, whereas those with BPTB and HS autografts continued to have significant delays in their BTT and TBT with BPTB (p = 0.007, p = 0.009) and HS (p = 0.016, p = 0.015), respectively. By six weeks post-operatively, braking parameters for patients receiving an ACL reconstruction with a hamstring autograft returned to normal values while those treated with a BPTB autograft continued to demonstrate impairment in brake travel time and total braking time compared to controls; however, their brake reaction time had recovered to normative values. Conclusion: Patients who underwent a right knee ACL reconstruction with a TA allograft regained normal braking times by three weeks post-operatively and continued to improve through the six week postoperative time point. In contrast, those treated with a BPTB or HS autograft demonstrated impaired ability to operate motor vehicle brakes three weeks following surgery. While at six weeks, the braking ability of patients treated with hamstring autografts normalized, those receiving a BPTB autograft continued to demonstrate limitations in their brake travel time and total braking time. Patients should be counseled appropriately when discussing reconstruction options and when it is safe to resume driving

Objectives: The purpose of the current study is to investigate the functional strength outcomes of late distal biceps reconstruction using allograft tissue. Methods: Patients who underwent distal biceps reconstruction with allograft tissue between May 2007 and May 2013 were identified. Charts were retrospectively reviewed for post-operative complications, gross flexion and supination strength, and range of motion (ROM). Isokinetic strength and endurance in elbow flexion and forearm supination were measured in both arms. Tests were conducted using a dynamometer at 60o per second for isokinetic strength and 240o per second for endurance. Isometric strength testing was also measured for elbow flexion and forearm supination. Paired t tests were used for statistical analysis. Results: Ten patients with a mean age of 48 years (range 42 - 61 years) were included in the study. Distal biceps reconstruction was performed using an Achilles tendon allograft in 9 patients and a combination of tibialis anterior allograft and gracilis allograft in 1 patient. Of the reconstructions, 50% involved the dominant arm. Full ROM was observed in all patients at the time of their final follow up assessment. The mean followup for dynamometer strength testing was 34 months (range 13-81 months). No statistical differences were noted between data obtained from operative and contralateral extremities. The average peak torque of the operative limb (38.5+/- 5.9 Nm) was 91.7% of that of the contralateral limb (41.8+/-4.9 Nm) in flexion and 93.4% (operative, 5.7+/-1.3 Nm; contralateral, 6.1+/- 1.0 Nm) in supination. No significant differences were found in fatigue index between operative or contralateral limbs for flexion (operative, 34.1+/-17.1%; contralateral, 30.8+/-17.1%; p = 0.29) or supination (operative, 38.2+/-16.5%; contralateral, 42.1+/-11.9%; p = 0.65). The only complication observed was a transient PIN palsy in one patient which resolved by 3 months post-operatively. All patients reported postoperative cosmetic deformity but found their gross appearance acceptable. Conclusion: Late reconstruction for chronic distal biceps rupture using allograft tissue is a safe and effective solution for symptomatic patients with functional demands in forearm supination and elbow flexion. Dynamometer testing shows near normal return of strength and endurance of both elbow flexion and supination following the procedure