For patients with cervical radiculopathy, total disc replacement using artificial disc devices that have become more widely used during the last 10 years presents a potential advance in treatment. It may preserve range-of-motion and decrease the need for later secondary surgery when compared to the standard anterior discectomy and spinal fusion. “Artificial disc devices can yield good results in the right patients,” notes Mark Knaub, MD, assistant professor and associate director of the Penn State Spine Center. However, Dr. Knaub explains that there are significant limitations to their usefulness: “These devices are not appropriate to use in patients with poor bone quality or disc disease affecting multiple levels, nor for patients with a pre-existing fusion, those who present with significant arthritis and those with already limited range-of-motion.” While clinical trials show improvement of symptoms with disc arthroplasty,1,2 there is controversy regarding whether a cervical disc arthroplasty can reduce the frequency of reoperations, compared with fusion.
Author Archives: kbrooks12014
Cartilage Grafting Options for Large or Microfracture-resistant Osteochondritis Dessican (OCD) Lesions of the Talus
Treatment options for large talar osteochondral lesions (greater than 1.5 cm) or those that fail to adequately respond to microfracture, have broadened over the last decade, with most procedures directly aimed at hyaline-like cartilage restoration. Michael Aynardi, MD, orthopaedic surgeon and assistant professor of orthopaedics, Penn State Bone and Joint Institute, says, “Patients with these types of lesions usually experience significant functional limitations and, due to lesion size, are not good candidates for microfracture and require a more invasive reconstructive approach.” Options include autologous chondrocyte implantation (ACI), osteochondral autograft transfer system (OATS), matrix-induced autologous chondrocyte implantation (MACI) and allograft cartilage grafting combined with the autologous mesenchymal stem cells (MSCs). Procedures such as OATS require a formal osteotomy to expose the lesion and gain access into the ankle joint to deliver the graft. Newer techniques such as MACI and allograft cartilage grafting can be performed without using an osteotomy and use a technique called distal tibial plafondplasty to access the joint.1 Continue reading
Regenerative medicine and tissue engineering for focal chondral defects of the knee joint aim to augment, repair, replace or regenerate the damaged cartilage caused by trauma or the natural aging process. Enrollment is underway at Penn State Health Milton S. Hershey Medical Center for a Phase III clinical trial of an autologous cartilage implant (NOVOCART® 3D, Aesculap Biologics, LLC/B. Braun, Inc.) for the repair of femoral cartilage defects.
Robert Gallo, MD, associate professor of sports medicine and the site principal investigator for this trial, explains, “Patients who experience knee pain and are limited in their activities because of a large cartilage defect on the distal femur are good potential candidates for this trial.” Such localized defects usually result from trauma or repetitive use during sports activity and are not seen in the setting of osteoarthritis or other arthropathies; patients with “kissing” lesions are not permitted to enroll. The NOVOCART 3D (three-dimensional) implant is a combination biologic device made by harvesting autologous chondrocytes from the patient, which are then sent to a central laboratory and expanded; the cells are then seeded onto a bioresorbable three-dimensional collagen-based matrix that is implanted at the defect site three weeks later.1
When patients need to return to what they consider to be their “normal life” and activity following orthopaedic injuries or surgery, there is little evidence-based guidelines for such assessment.
Despite potentially impactful financial, medical and legal implications of such decisions, little is standardized to help assist orthopaedists make safe recommendations. Kenneth Taylor, MD, associate professor and chief, hand surgery, Bone and Joint Institute, says, “Orthopaedists routinely make decisions about what activities a patient can safely engage in after an injury or surgery. Questions come up about when he or she can drive, go back to work or return to team sports.” He notes, “Part of the problem is the issue is incredibly broad. It occurs across various orthopaedic issues and touches on many different activities.” In most cases, these decisions involve patients with an upper or lower extremity that has undergone repair; activities include important areas of functioning like driving, work and school. In response, Dr. Taylor is currently developing a research protocol to identify factors that reliably predict a patient’s readiness to return to driving, an issue that impacts nearly all adult patients in the orthopaedic clinic setting. Continue reading
Measurement of Tibial Tubercle to Trochlear Groove (TT-TG) Distance by MRI for Patellofemoral Instability
Patellar instability, with repeated lateral dislocation, commonly seen in younger, active adults, is associated with a number of anatomical pathologies and usually requires surgical intervention. Among these, increased tibial tubercle to trochlear groove (TT-TG) distance is a prominent risk factor. TT-TG distance describes the degree of lateralization of the tibial tubercle. “TT-TG distance is routinely measured in most patients who present with a partial or complete knee-cap dislocation. This makes it an accessible piece of information that could potentially be used to identify patients at-risk for repeated dislocations,” explains Paul Sherbondy, M.D., Bone and Joint Institute.
Novel Pin Array Guide Boosts Accuracy of Glenoid Component Positioning in Total Shoulder Arthroplasty
Achieving accurate glenoid component placement during total shoulder arthroplasty is one of the most challenging aspects of the procedure. In most cases, there is substantial arthritis-related bone deformity with limited exposure of the glenoid surface intra-operatively, making it difficult to visualize. April D. Armstrong, M.D., chief, shoulder and elbow surgery, Bone and Joint Institute, says, “When the glenoid component isn’t accurately placed, it tends to loosen and eventually requires a revision procedure.” Using traditional placement techniques in one investigation, errors in version and inclination of the central drill line, on average, were approximately 9 degrees and version error correlated with the degree of arthritic glenoid version.¹ Continue reading
One of the most challenging scenarios is the patient with a complex hindfoot deformity involving both the ankle and the subtalar joint. “Hindfoot deformities involve complex anatomy, and may be caused by trauma, arthritis, congenital disease or may be related to Charcot neuropathy,” explains Paul J. Juliano, M.D., chief, foot and ankle orthopaedics, Bone and Joint Institute. Tibiotalocalcaneal (TTC) arthrodesis, often paired with osteotomy, is a salvage procedure typically performed in patients with severe tibiotalar and subtalar arthropathy with a significant pre-operative deformity. Over the past 10 to 15 years, treatment has shifted away from external fixation to internal fusion achieved with an intra-medullary nail.1,2 Continue reading