JAAOS, Volume 20, No. 4

Radiographic Analysis of Spondylolisthesis and Sagittal Spinopelvic Deformity

Traditional radiographic analysis of spondylolisthesis focuses on the regional sagittal deformity at the lumbosacral junction. Pelvic morphology has also been cited as an important factor that contributes to the development of high-grade spondylolisthesis. However, the importance of global sagittal balance of the spine and pelvis in patients with spondylolisthesis has been emphasized recently. Patients with this condition can develop abnormal sagittal spinopelvic balance; restoration of sagittal spinal alignment can improve their health-related quality of life. Reduction has been used to restore alignment, but its role in the management of high-grade spondylolisthesis is controversial. None of the current classification systems take sagittal sacropelvic and spinopelvic balance into account. Improved understanding of the relationship between the spine and pelvis has led to the development of a new classification system that incorporates analysis of spinopelvic balance in the radiographic assessment. This new system may aid surgeons in identifying patients who would benefit from a partial reduction procedure.

      • Subspecialty:
      • Spine

    Management of Pediatric Trigger Thumb and Trigger Finger

    Pediatric trigger thumb and trigger finger represent distinct conditions and should not be treated like adult acquired trigger finger. Over the last two decades, our understanding of the natural history of pediatric trigger thumb and the etiology and surgical management of pediatric trigger finger has improved. Pediatric trigger thumb may spontaneously resolve, although resolution may take several years. Open surgical release of the A1 pulley of the thumb is an alternative option that nearly uniformly restores thumb interphalangeal joint motion. Surgical management of pediatric trigger finger with isolated release of the A1 pulley has been associated with high recurrence rates. Awareness of the anatomic factors that may contribute to triggering in the pediatric finger and willingness to explore and address other involved components of the flexor mechanism can prevent surgical failure.

        • Subspecialty:
        • Hand and Wrist

      Modularity of the Femoral Component in Total Hip Arthroplasty

      Modular femoral components have been developed to aid in recreating native femoral version, limb length, and offset in total hip arthroplasty. Use of modular implants results in cost savings, as well. Inventory can be reduced while allowing intraoperative flexibility and options. With modular implants, the femoral prosthesis can be built in situ, which is helpful in minimizing incision length and surgical dissection. However, additional modular junctions are associated with increased concern for component failure through taper fretting, fatigue fracture, and local corrosion, which may contribute to elevated serum metal ion levels. The recent trend toward using larger diameter femoral heads may impart higher loads and stress than were seen previously. Although modular components offer a plethora of intraoperative options in primary and revision total hip arthroplasty, the long-term effects of these additional junctions remains unknown.

          • Subspecialty:
          • Adult Reconstruction

        Medial Epicondyle Fractures in the Pediatric Population

        Humeral medial epicondyle fractures in the pediatric population account for up to 20% of elbow fractures, 60% of which are associated with elbow dislocation. Isolated injuries can occur from either direct trauma or avulsion. Medial epicondyle fractures also occur in combination with elbow dislocations. Traditional management by cast immobilization increasingly is being replaced with early fixation and mobilization. Relative indications for surgical fixation include ulnar nerve entrapment, gross elbow instability, and fractures in athletic or other patients who require high-demand upper extremity function. Absolute indications for surgical intervention are an incarcerated fragment in the joint or open fractures. Radiographic assessment of these injuries and their true degree of displacement remain controversial.

            • Subspecialty:
            • Shoulder and Elbow

            • Pediatric Orthopaedics

          Aneurysmal Bone Cyst

          Aneurysmal bone cysts are rare skeletal tumors that most commonly occur in the first two decades of life. They primarily develop about the knee but may arise in any portion of the axial or appendicular skeleton. Pathogenesis of these tumors remains controversial and may be vascular, traumatic, or genetic. Radiographic features include a dilated, radiolucent lesion typically located within the metaphyseal portion of the bone, with fluid-fluid levels visible on MRI. Histologic features include blood-filled lakes interposed between fibrous stromata. Differential diagnosis includes conditions such as telangiectatic osteosarcoma and giant cell tumor. The mainstay of treatment is curettage and bone graft, with or without adjuvant treatment. Other management options include cryotherapy, sclerotherapy, radionuclide ablation, and en bloc resection. The recurrence rate is low after appropriate treatment; however, more than one procedure may be required to completely eradicate the lesion.

              • Subspecialty:
              • Musculoskeletal Oncology

            The Hill-Sachs Lesion: Diagnosis, Classification, and Management

            The Hill-Sachs lesion is an osseous defect of the humeral head that is typically associated with anterior shoulder instability. The incidence of these lesions in the setting of glenohumeral instability is relatively high and approaches 100% in persons with recurrent anterior shoulder instability. Reverse Hill-Sachs lesion has been described in patients with posterior shoulder instability. Glenoid bone loss is typically associated with the Hill-Sachs lesion in patients with recurrent anterior shoulder instability. The lesion is a bipolar injury, and identification of concomitant glenoid bone loss is essential to optimize clinical outcome. Other pathology (eg, Bankart tear, labral or capsular injuries) must be identified, as well. Treatment is dictated by subjective and objective findings of shoulder instability and radiographic findings. Nonsurgical management, including focused rehabilitation, is acceptable in cases of small bony defects and nonengaging lesions in which the glenohumeral joint remains stable during desired activities. Surgical options include arthroscopic and open techniques.

                • Subspecialty:
                • Shoulder and Elbow

                • Sports Medicine

              Management of Calcaneal Tuberosity Fractures

              Fractures of the calcaneal tuberosity are relatively uncommon and are seen most frequently in elderly and diabetic patients. These injuries are typically avulsion fractures caused by concentric contraction of the gastrocnemius-soleus muscle complex. Displacement of these fractures can compromise the skin over the posterior aspect of the heel; therefore, early recognition and management are imperative. Surgical management of calcaneal tuberosity fractures requires reduction and stable fixation of the displaced fragment. When the patient has preexisting tightness of the gastrocnemius-soleus complex, successful management must also address this pathology to improve outcome.

                  • Subspecialty:
                  • Foot and Ankle

                  • Trauma