Faculty Bibliography

Objective Focal chondral defects alter joint mechanics and cause pain and debilitation. Microfracture is a surgical technique used to treat such defects. This technique involves penetration of subchondral bone to release progenitor cells and growth factors from the marrow to promote cartilage regeneration. Often this results in fibrocartilage formation rather than structured hyaline cartilage. Some reports have suggested use of growth hormone (GH) with microfracture to augment cartilage regeneration. Our objective was to test whether intra-articular (IA) GH in conjunction with microfracture, improves cartilage repair in a rabbit chondral defect model. We hypothesized that GH would exhibit a dose-dependent improvement in regeneration. Design Sixteen New Zealand white rabbits received bilateral femoral chondral defects and standardized microfracture repair. One group of animals ( n = 8) received low-dose GH by IA injection in the left knee, and the other group ( n = 8) received high-dose GH in the same manner. All animals received IA injection of saline in the contralateral knee as control. Serum assays, macroscopic grading, and histological analyses were used to assess any improvements in cartilage repair. Results Peripheral serum GH was not elevated postoperatively ( P = 0.21). There was no improvement in macroscopic grading scores among either of the GH dosages ( P = 0.83). Scoring of safranin-O-stained sections showed no improvement in cartilage regeneration and some evidence of increased bone formation in the GH-treated knees. Conclusions Treatment with either low- or high-dose IA GH does not appear to enhance short-term repair in a rabbit chondral defect model.

Diffuse idiopathic skeletal hyperostosis (DISH) is common spinal condition characterized by increased calcification and ossification of ligaments and entheses, typically in the anterior aspect of the spine. However, extraspinal manifestations of the disease can occur and depending on the degree and location of involvement, may become symptomatic. We present the case of a 63-year-old male with a history of DISH, who failed initial open distal clavicle excision due to the postoperative development of heterotopic bone bridging across the acromioclavicular joint. Revision open distal clavicle excision coupled with postoperative heterotopic ossification prophylaxis led to a successful clinical and functional outcome without heterotopic bone recurrence. The case description is followed by a review of the extraspinal manifestations of DISH and the recommended prophylactic management in patients with DISH and similar risk factors for the development of heterotopic ossification.

Over recent years, appreciation for the critical role of the meniscus in joint biomechanics has led to an emphasis on meniscal preservation. Meniscal allograft transplant (MAT) is a promising biological solution for the symptomatic young patient with a meniscus-deficient knee that has not developed advanced osteoarthritis. As surgical techniques are refined and outcomes continue to improve, it is vital to consider the utility of such procedures and offer a straightforward approach to MAT. This article and accompanying video provide a step-by-step tutorial on how to perform a MAT using the bridge and slot technique, its key pearls and pitfalls as well as the relevant advantages and disadvantages of MAT.

The meniscus plays a vital role in knee biomechanics, and its physical absence or functional incompetence (e.g., irreparable root or radial tear) leads to unacceptably high rates of joint degeneration in affected populations. Meniscal allograft transplantation has been used successfully to treat patients with postmeniscectomy syndrome, and there is early laboratory and radiographic evidence hinting at a potential prophylactic role in preventing joint degeneration. We present a technique for lateral meniscal allograft transplantation using the CONMED Meniscal Allograft Transplantation system.

The posteromedial corner of the knee encompasses five medial structures posterior to the medial collateral ligament. With modern MRI systems, these structures are readily identified and can be appreciated in the context of multiligamentous knee injuries. It is recognized that anteromedial rotatory instability results from an injury that involves both the medial collateral ligament and the posterior oblique ligament. Like posterolateral corner injuries, untreated or concurrent posteromedial corner injuries resulting in rotatory instability place additional strain on anterior and posterior cruciate ligament reconstructions, which can ultimately contribute to graft failure and poor clinical outcomes. Various options exist for posteromedial corner reconstruction, with early results indicating that anatomic reconstruction can restore valgus stability and improve patient function. A thorough understanding of the anatomy, physical examination findings, and imaging characteristics will aid the physician in the management of these injuries.

Osteoarthritis (OA) is a degenerative joint condition characterized by painful cartilage lesions that impair joint mobility. Current treatments such as lavage, microfracture, and osteochondral implantation fail to integrate newly formed tissue with host tissues, and establish a stable transition to subchondral bone. Similarly, tissue engineered grafts that facilitate cartilage and bone regeneration likewise are challenged by how to integrate the graft seamlessly with surrounding host cartilage and/or bone. This review centers on current approaches in promoting cartilage graft integration. It begins with an overview of articular cartilage structure and function, as well as degenerative changes to this relationship attributed to aging, disease, and trauma. A discussion of the current progress in integrative cartilage repair then follows, focusing on graft or scaffold design strategies targeting cartilage-cartilage and/or cartilage-bone integration. It is emphasized that integrative repair is required to ensure long term success of the cartilage graft and preserve the integrity of the newly engineered articular cartilage. Studies involving the use of enzymes, choice of cell source, biomaterial selection, growth factor incorporation, and stratified versus gradient scaffolds are therefore highlighted here. Moreover, models that accurately evaluate the ability of cartilage grafts to enhance tissue integrity and prevent ectopic calcification are also discussed. A summary and future directions section concludes the review.

OBJECTIVES: Meniscus tears are one of the most common knee injuries. Our goal is to investigate the failure rate for surgically repaired bucket-handle meniscus tears and compare clinical outcomes of repairs that failed versus those that did not, at a minimum 2-year follow-up interval. METHODS: 51 patients were identified in this retrospective cohort study who experienced bucket-handle meniscus tears that were isolated or with concomitant ACL injury. Inclusion criteria included age range from 13-55 years, confirmed bucket-handle meniscus tear by MRI and intraoperatively, and at least two-years of post-operative follow-up following index repair. Demographic data and outcome surveys were collected at a minimum of two-years follow-up after repair. RESULTS: Of the 51 patients that had a bucket-handle meniscal repair, 12 (23.5%) were defined as failures (return of symptoms alongside re-tear in the same zone of the repaired meniscus within two years of surgery). No demographic variables (age, sex, and BMI smoking status, location of tear, or concomitant ACL tear) significantly correlated with failure. The mean of the Sports and Recreation KOOS was significantly lower between the non-failure (87+/-14.4) and failure (70+/-17.2) cohorts (p=0.0072). The Quality of Life subscale was significantly lower between the non-failure (76+/-15.8) and failure (57+/-18.2) groups (p=0.0058). There was a significant difference in the post-operative Lysholm scores (p=0.0039) with a mean of 90+/-9.1 for the entire cohort and means of 92+/-8.4 and 83+/-8.6, for non-failure and failure groups, respectively. CONCLUSIONS: We found a higher failure rate (23.5%) for bucket-handle meniscus repairs at two-year follow up than has been cited in the literature, which is typically less than 20%, with significantly lower KOOS Quality of Life and Sports and Recreation subscales and Lysholm scores for the failure cohort. This is the first study to report these outcome scores solely for bucket-handle meniscus repairs, shedding light on the post-operative quality of life of patients with repair success or failure.

Objectives: Continuous gradient-echo (GRE) acquisition or "dynamic magnetic resonance imaging", allows for high-speed examination of pathologies based on joint motion. We sought to assess the efficacy of a radial GRE sequence with in the characterization of patellofemoral maltracking. Methods: Patients with suspected patellofemoral maltracking and asymptomatic volunteers were scanned using GRE (Siemens LiveView WIP; Malvern, PA, USA) at 3T in the axial plane at the patella level through a range of flexion-extension (0-30degree). The mean time to perform the dynamic component ranged from 3-7 mins. Lateral maltracking (amount patella moved laterally through knee ranging) was measured. Patella lateralization was categorized as normal (<= 2mm), mild (2-5mm), moderate (5-10mm), or severe (>10mm). Tibial tuberosity: trochlear groove (TT: TG) distance, trochlea depth, Insall-Salvati ratio, and patellofemoral cartilage quality (according to the modified Outerbridge grading system) were also assessed. Results: Eighteen symptomatic (6 men; 12 women, age range 14-51 years) and 10 asymptomatic subjects (6 men; 4 women, age range 25-68 years) were included. Two symptomatic patients underwent bilateral examinations. Lateralization in the symptomatic group was normal (n=10), mild (n=2), moderate (n=5) and severe (n=3). There was no abnormal maltracking in the volunteer group. Lateral tracking significantly correlated with TT: TG distance (F=38.0; p<.0001), trochlea depth (F=5.8; p=.023), Insall-Salvati ratio (F=4.642; p=.04) and Outerbridge Patella score (F=6.6; p=.016). Lateral tracking did not correlate with Outerbridge Trochlear score. Conclusion: Lateral tracking measured on GRE was found to significantly correlate with current measures of patellar instability including, TT: TG, trochlea depth, and the Insall-Salvati ratio. GRE is a rapid and easily performed addition to the standard protocol for kinematic patellofemoral motion and can add dynamic information on patellofemoral tracking. This may be help determine if an isolated MPFL or an MPFL reconstruction and tibial tubercle osteotomy is needed to treat patella instability

We retrospectively reviewed the records of 3 patients (3 knees) with a delayed type hypersensitivity reaction following Dermabond exposure after an orthopaedic knee procedure. Delayed hypersensitivity reactions are mediated by CD4+ helper T cells. The use of skin adhesives in place of traditional sutures is increasing in popularity given Dermabond's potential benefits of decreased wound infection rate and better wound approximation. However, hypersensitivity reactions to the cyanoacrylate material in Dermabond have been described. Differentiating hypersensitivity reactions from post-operative infections is important as septic arthritis is a potentially devastating complication. This case series presents the challenge of properly diagnosing and managing hypersensitivity reactions. Consultation with allergists and dermatologists may be appropriate for ascertaining the nature of the surgical site complication and proper management. The recommended management of hypersensitivity-type reactions is a course of topical steroids and infection work up if needed.