JAAOS, Volume 21, No. 9

Patient-specific Instruments for Total Knee Arthroplasty

The use of patient-specific instruments for total knee arthroplasty shifts computer navigation for bone landmark registration and implant positioning from the intraoperative to the preoperative setting. Each system requires preoperative MRI or CT, with specifications determined by the instrument manufacturer. The marketed advantages of patient-specific instruments include greater accuracy in coronal alignment with fewer outliers, no need for instrumentation of the intramedullary canal, reduced surgical time, lower hospital costs, and improved clinical outcomes. The few published results of these instruments suggest minimal gains obtained in hospital logistics variables and minimal evidence of improvement in either alignment or patient outcomes. Disadvantages of patient-specific instruments include increased costs for imaging and instrument fabrication as well as increased preoperative time required for surgical planning and reviewing the instrument plans, and the learning curve for the surgeon to work with the engineers and use these instruments intraoperatively. It is also necessary to have a set of standard instruments available in case the patient-specific instruments do not work properly. Additional data are required before deciding whether these instruments should be recommended.

      • Subspecialty:
      • Adult Reconstruction

    Choosing Fusion Levels in Adolescent Idiopathic Scoliosis

    Correct identification of fusion levels in surgical planning for the management of adolescent idiopathic scoliosis is a complex task. Several classification systems and algorithms exist to assist surgeons in determining the appropriate levels to be instrumented. The Lenke classification is the benchmark system. Among the many factors and measurements that are taken into account when selecting the proper upper instrumented vertebra and lower instrumented vertebra are planning for selective fusion; preserving motion segments; preventing proximal and/or distal junctional kyphosis, shoulder imbalance, and neck pain; and maintaining short fusion lengths. Existing treatment algorithms do not account for every exception, and further research is required to improve long-term surgical outcomes.

        • Subspecialty:
        • Pediatric Orthopaedics

      Management of Shoulder Instability in the Skeletally Immature Patient

      Several studies have focused on management of shoulder instability in the adolescent and young adult population. However, a paucity of literature exists regarding shoulder dislocation in the skeletally immature population. The presence of an open physis makes the dislocated pediatric shoulder a challenging clinical problem. In general, management includes prompt reduction and sling immobilization. In athletic patients aged ?14 years with a Bankart lesion, early surgical intervention may be warranted because of the higher risk of recurrent instability. However, the literature on younger skeletally immature patients is less clear in terms of risk of further instability and the necessity of surgical intervention. In the skeletally immature population, a relatively low rate of recurrent instability after primary dislocation has been reported in the recent literature. Surgical intervention should be considered for patients with recurrent instability.

          • Subspecialty:
          • Shoulder and Elbow

        Proximal Humerus and Humeral Shaft Nonunions

        The rate of nonunion is estimated to be 1.1% to 10% following closed treatment of proximal humerus fracture and 5.5% following closed treatment of humeral shaft fracture. Surgical management should be considered for fractures that demonstrate no evidence of progressive healing on consecutive radiographs taken at least 6 to 8 weeks apart during the course of closed treatment. In the case of proximal humerus nonunion, recent series have demonstrated union in >90% of patients treated with reconstruction using locking plates and autogenous bone graft. Shoulder arthroplasty is reserved as a salvage option in cases in which the humeral head is not viable or the proximal fragment will not support osteosynthesis. For humeral shaft nonunions, open reduction and internal fixation with compression plating and bone graft remains the standard of care, with a >90% rate of union and good functional outcomes. Recent studies support the use of locked compression plates, dual plating, and cortical allograft struts in patients with osteopenic bone.

            • Subspecialty:
            • Trauma

          Comprehensive Approach to the Evaluation of Groin Pain

          Groin pain is often related to hip pathology. As a result, groin pain is a clinical complaint encountered by orthopaedic surgeons. Approximately one in four persons will develop symptomatic hip arthritis before age 85 years. Groin injuries account for approximately 1 in 20 athletic injuries, and groin pain accounts for 1 in 10 patient visits to sports medicine centers. Many athletes with chronic groin pain have multiple coexisting pathologies spanning several disciplines. In treating these patients, the orthopaedic surgeon must consider both musculoskeletal groin disorders and nonorthopaedic conditions that can present as groin pain. A comprehensive history and physical examination can guide the evaluation of groin pain.

              • Subspecialty:
              • Basic Science

            Treatment of Osteoarthritis of the Knee: Evidence-Based Guideline, 2nd Edition

            Treatment of Osteoarthritis of the Knee: Evidence-Based Guideline, 2nd Edition, is based on a systematic review of the current scientific and clinical research. This guideline contains 15 recommendations, replaces the 2008 AAOS clinical practice guideline, and was reevaluated earlier than the 5-year recommendation of the National Guideline Clearinghouse because of methodologic concerns regarding the evidence used in the first guideline. The current guideline does not support the use of viscosupplementation for the treatment of osteoarthritis of the knee. In addition, the work group highlighted the need for better research in the treatment of knee osteoarthritis.