JAAOS, Volume 13, No. 8

Process and tubercle fractures of the hindfoot.

Process and tubercle fractures of the talus and calcaneus can be a source of significant pain and dysfunction. Successful management requires extensive knowledge of the complex osseoligamentous anatomy of the hindfoot. The large posterior process of the talus is composed of a medial and a lateral tubercle; an os trigonum may exist posterior to the lateral tubercle. The talus has a lateral process that articulates with the fibula and subtalar joint; the calcaneus possesses a frequently injured anterior process that articulates with the cuboid. Injury to these hindfoot structures is caused by inversion and eversion of the ankle, which can occur during athletic activity. These injuries often are misdiagnosed as ankle sprains. A high degree of clinical suspicion is warranted, and specialized radiographs or other imaging modalities may be required for accurate diagnosis. Nonsurgical management with cast immobilization is frequently successful when the fracture is correctly diagnosed acutely. Large fragments may be amenable to open reduction and internal fixation. Untreated, chronic injuries can cause significant pain and functional impairment that may be improved substantially with late surgical intervention.

    • Keywords:
    • Calcaneus|Foot|Fractures

    • Bone|Humans|Magnetic Resonance Imaging|Physical Examination|Radiopharmaceuticals|Talus|Tomography

    • X-Ray Computed

    • Subspecialty:
    • Foot and Ankle

    • Trauma

Hinged elbow external fixators: indications and uses.

Hinged external fixation of the elbow joint can play an important role in managing complicated fracture-dislocations, joint instability after extensive contracture release, and distraction interposition arthroplasty. Application of these devices requires accurate alignment of the fixator axis with the anatomic axis of the elbow. The primary therapeutic goal is to allow joint motion while protecting the healing ligaments. Common complications include pin loosening, injury to adjacent neurovascular structures, cellulitis, and loss of reduction. Although reported data are limited, this technique is a useful adjunct in patients with complex elbow instability.

    • Keywords:
    • Contracture|Dislocations|Elbow Joint|External Fixators|Fracture Fixation|Fractures

    • Bone|Humans|Joint Instability|Prosthesis Design|Range of Motion

    • Articular

    • Subspecialty:
    • Trauma

    • Shoulder and Elbow

Constraint in primary total knee arthroplasty.

Instability is an important cause of failure following total knee arthroplasty. Increasing component constraint may reduce instability, but doing so also can cause increased forces to be transmitted to fixation and implant interfaces, which may lead to premature aseptic loosening. Constraint is defined as the effect of the elements of knee implant design that provides the stability needed to counteract forces about the knee after arthroplasty in the presence of a deficient soft-tissue envelope. Determining the amount of constraint necessary can be challenging. Most primary total knee arthroplasties are performed for knees without substantial deformity or the need for difficult ligament balancing; in these cases, either a posterior-stabilized or a posterior cruciate-retaining design is appropriate. In certain situations, such as patients with prior patellectomies, rheumatoid arthritis, or substantial preoperative deformities, a posterior-stabilized knee may be favored. With their large posts, varus-valgus constrained implants typically are reserved for patients with substantial coronal plane instability, which is difficult to balance with a posterior-stabilized or cruciate-retaining implant alone. Rotating-hinge knee implants usually are recommended for patients with severe deformity or instability that cannot be managed with a varus-valgus implant.

    • Keywords:
    • Arthroplasty

    • Replacement

    • Knee|Humans|Joint Instability|Knee Prosthesis|Prosthesis Design|Prosthesis Failure|Reoperation

    • Subspecialty:
    • Adult Reconstruction

The use of ultrasound in evaluating orthopaedic trauma patients.

Musculoskeletal ultrasound is a low-cost, noninvasive method of evaluating orthopaedic trauma patients. It is particularly useful for patients with metallic hardware, which may degrade computed tomography or magnetic resonance images. Ultrasound has been used to evaluate fracture union and nonunion, infection, ligamentous injury, nerve compression, and mechanical impingement caused by hardware. Real-time dynamic examination allows identification of pathology and provides direct correlation between symptoms and the observed pathology.

    • Keywords:
    • Humans|Musculoskeletal Diseases|Musculoskeletal System|Prostheses and Implants|Wounds and Injuries

    • Subspecialty:
    • General Orthopaedics

    • Trauma

Anterior knee pain: diagnosis and treatment.

Anterior knee pain is a frequent clinical problem. It provides a common challenge to diagnose and manage. Basic science studies have provided insight into the origin of anterior knee pain and refined understanding of the anatomy. Clinical evaluation has progressively focused on the contribution of the entire lower extremity to patellofemoral function. Nonsurgical management has been refined by the concept of the "envelope of function" and by increased understanding of the neuromuscular control of the knee. Indications for lateral release have been clarified and narrowed. Although anteromedial transfer of the tibial tuberosity is helpful in certain circumstances, reports of postoperative fracture have led to less aggressive rehabilitation protocols. Chondral resurfacing of the patellofemoral joint and patellofemoral arthroplasty are evolving. Emphasis should remain on nonsurgical management, which is sufficient in most patients.

    • Keywords:
    • Arthralgia|Humans|Knee|Knee Injuries|Knee Joint|Pain

    • Subspecialty:
    • Sports Medicine

Oncologic approaches to pediatric limb preservation.

Preservation of limb function in the pediatric oncology patient is uniquely challenging. Treatment must be strictly prioritized in terms of the patient's life, the limb, its function, length equalization, and cosmetic appearance. At the same time, social, socioeconomic, and cultural factors must be understood and respected to achieve the most advantageous outcome for both the patient and family. Given these considerations, as well as the relative rarity of many oncologic diagnoses and the myriad of presentation scenarios, drafting generalized treatment recommendations is difficult. Instead, orthopaedic intervention in the care of children and young adults with oncologic conditions must be individualized, with the broad goal being optimization of limb function rather than rigid advocacy of limb salvage.

    • Keywords:
    • Amputation|Bone Neoplasms|Humans|Limb Salvage|Medical Oncology|Pediatrics|Prostheses and Implants|Soft Tissue Neoplasms

    • Subspecialty:
    • Musculoskeletal Oncology

    • Pediatric Orthopaedics