Faculty Bibliography

Meniscal tears are common injuries that may result in functionally limiting pain, swelling, and mechanical symptoms. The management of meniscal pathology has evolved as surgeons' understanding of the important role the menisci play in normal knee kinematics increases. Recent emphasis on partial meniscectomy, expanding indications for meniscal repair, and the increased use of meniscal allograft transplantation have helped improve the outcomes of patients with a meniscal tear who undergo treatment. Orthopaedic surgeons should understand meniscal function, pathology, and treatment approaches.

Management of proximal and distal biceps tendon pathology is evolving. The long head of the biceps tendon, if inflamed, may be a pain-producing structure. In appropriately indicated patients, a symptomatic long head of the biceps tendon can be surgically managed via tenotomy, tenodesis, and/or superior labrum anterior to posterior repair. In some patients, primary superior labrum anterior to posterior pathology can be managed via biceps tenodesis. Determining which procedure is most appropriate for and which technique and implant are preferred in a given patient with biceps tendon pathology is controversial. Less debate exists with regard to the timing of distal biceps tendon repair; however, considerable controversy exists with regard to selection of an appropriate surgical technique and implant. In addition, the treatment of patients with a chronic and/or retracted distal biceps tendon tear and patients in whom distal biceps tendon repair fails is extremely challenging. Orthopaedic surgeons should understand the anatomy of, nonsurgical and surgical treatment options for, and outcomes of patients with proximal or distal biceps tendon pathology.

The management of complex cartilage and meniscal pathology in young, athletic patients is extremely challenging. Joint preservation surgery is most difficult in patients with concomitant knee pathologies, including cartilage defects, meniscal deficiency, malalignment, and/or ligamentous insufficiency. Clinical decision making for these patients is further complicated by articular cartilage lesions, which often are incidental findings; therefore, treatment decisions must be based on the confirmed contribution of articular cartilage lesions to symptomatology. Surgical management of any of the aforementioned knee pathologies that is performed in isolation typically results in acceptable patient outcomes; however, concomitant procedures for the management of concomitant knee pathologies often are essential to the success of any single procedure. The use of biologic therapy as an alternative to or to augment more conventional surgical management has increased in popularity in the past decade, and indications for biologic therapy continue to evolve. Orthopaedic surgeons should understand knee joint preservation techniques, including biologic and reconstructive approaches in young, high-demand patients.

Small animal models are critical for studies of sports-related knee injury and disease such as posttraumatic osteoarthritis (PTOA) following anterior cruciate ligament (ACL) rupture. In such models, ACL damage can be achieved by surgical transection or, using a more recent innovation, by noninvasive biomechanical means. Whether these approaches differentially alter normal mechanics is unknown. Furthermore, while surgical reconstruction of ruptured ACL can greatly improve joint stability, its effect on PTOA development is also unclear. Our primary purpose was to characterize rodent knee joint mechanics in two models of ACL rupture using a novel quantitative laxity mechanical test. Our secondary aim was to characterize a new reconstruction technique using autograft tail tendon, and to assess its effect on joint mechanics. Our hypothesis was that surgical ACL transection would have a greater effect on joint mechanics. A total of 24 rat knee specimens underwent surgical or biomechanical ACL rupture and were stabilized using a new reconstruction technique using autograft tail tendon. Joint mechanics were assessed three times; preinjury, postinjury, and again after reconstruction, using quantitative joint laxity testing. Primary test readouts were maximum anteroposterior (AP) laxity, loading curve slope, and energy absorption. Student's t-tests were performed to identify intragroup differences. All surgical transections were completed successfully; maximum load in the biomechanical model was 67 +/- 7.7 N, with a coefficient of variation of 11.43%. Surgical transection caused increased AP laxity, while biomechanical injury nonsignificantly increased this parameter. In both cases, these changes recovered to baseline by reconstruction. Loading curve slope was reduced in both models and was also returned to baseline by repair. Energy absorption followed the same pattern except it remained significantly different from baseline postreconstruction in the surgical group. This study supports our hypothesis knee joint mechanics is differentially affected by injury mechanism in a small animal model. We also report a novel reconstruction technique in this model, using autograft tail tendon.

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.