JAAOS

JAAOS, Volume 20, No. 9


Bone Morphogenetic Protein in Spine Surgery: Current and Future Uses

The clinical use of bone morphogenetic protein (BMP) in spinal fusion surgery has recently become controversial. After its approval by the US FDA in July 2002, BMP was adopted by many spine surgeons as a replacement for the more traditional iliac crest bone graft to avoid the complications associated with bone graft harvest. However, as broad clinical use escalated, reports increased of potentially serious complications associated with BMP. Controversy continues, particularly regarding the safety of BMP and whether it should routinely replace iliac crest bone graft for spinal fusion surgery.

      • Subspecialty:
      • Spine

    Carpal Instability Nondissociative

    Carpal instability nondissociative (CIND) represents a spectrum of conditions characterized by kinematic dysfunction of the proximal carpal row, often associated with a clinical "clunk." CIND is manifested at the midcarpal and/or radiocarpal joints, and it is distinguished from carpal instability dissociative (CID) by the lack of disruption between bones within the same carpal row. There are four major subcategories of CIND: palmar, dorsal, combined, and adaptive. In palmar CIND, instability occurs across the entire proximal carpal row. When nonsurgical management fails, surgical options include arthroscopic thermal capsulorrhaphy, soft-tissue reconstruction, or limited radiocarpal or intercarpal fusions. In dorsal CIND, the capitate subluxates dorsally from its reduced resting position. Dorsal CIND usually responds to nonsurgical management; refractory cases respond to palmar ligament reefing and/or dorsal intercarpal capsulodesis. Combined CIND demonstrates signs of both palmar and dorsal CIND and can be treated with soft-tissue or bony procedures. In adaptive CIND, the volar carpal ligaments are slackened and are less capable of inducing the physiologic shift of the proximal carpal row from flexion into extension as the wrist ulnarly deviates. Treatment of choice is a corrective osteotomy to restore the normal volar tilt of the distal radius.

        • Subspecialty:
        • Hand and Wrist

      Glenoid Bone Loss in Primary Total Shoulder Arthroplasty: Evaluation and Management

      Glenohumeral osteoarthritis is the most common reason for shoulder replacement. Total shoulder arthroplasty provides reliable pain relief and restoration of function, with implant survivorship reported at 85% at 15 years. Glenoid component wear and aseptic loosening are among the most common reasons for revision. Glenoid wear characteristics have been correlated with, among other things, the degree of anatomic glenoid version correction. Anatomic glenoid reconstruction is particularly challenging in the presence of glenoid bone deficiency. Walch classified glenoid morphology into five types: type A, centered, without posterior subluxation but with minor erosion (A1) or major erosion (A2); type B, posteriorly subluxated (B1) or posteriorly subluxated with posterior glenoid erosion (B2); and type C, excessive glenoid retroversion. The type A glenoid represents only 59% of patients; thus, the need to address glenoid deformity is common. Methods of correction include asymmetric reaming of the anterior glenoid, bone grafting of the posterior glenoid, and implanting a specialized glenoid component with posterior augmentation. In many cases of type C or hypoplastic glenoid, the humerus is concentrically reduced in the deficient glenoid and glenoid deformity may not need to be corrected. Severely hypoplastic glenoid may require the use of bone-sparing glenoid components or reverse total shoulder arthroplasty.

          • Subspecialty:
          • Shoulder and Elbow

        Musculoskeletal Care of the Hemophiliac Patient

        Hemophilia is caused by a deficiency of clotting factor VIII or IX and is inherited by a sex-linked recessive pattern. von Willebrand disease, a common, moderate bleeding disorder, is caused by a quantitative or qualitative protein deficiency of von Willebrand factor and is inherited in an autosomal dominant or recessive manner. The most important clinical strategy for the management of patients with hemophilia is the avoidance of recurrent hemarthrosis by continuous, intravenous hematologic prophylaxis. Early hemarthrosis should be aggressively managed with aspiration and clotting factor concentrate until the joint examination is normal. Starting prophylactic factor replacement in infancy may prevent chronic synovitis and arthropathy. The natural history of poorly controlled disease is polyarticular hemophilic arthropathy; functional prognosis is poor. Patients with chronic synovitis may be treated effectively with radiosynovectomy; those who develop joint surface erosions may require realignment osteotomies, joint arthroplasty, and treatment of pseudotumors. Reconstructive surgery for hemophilic arthropathy, especially in patients with factor inhibitor, requires careful hematologic management by an experienced, multidisciplinary team.

            • Subspecialty:
            • Basic Science

          Pulmonary Embolism in Orthopaedic Patients: Diagnosis and Management

          Orthopaedic patients are at particularly high risk for pulmonary embolism. There has been a trend recently toward overdiagnosis of pulmonary embolism; thus, evaluation of the nature of a clinically relevant pulmonary embolism is needed, as is assessment of the timing, risks, and outcomes of therapeutic anticoagulation in surgical patients. Recent literature shows the incidence of pulmonary embolism to be increasing without a corresponding increase in mortality, suggesting that not all emboli may be clinically relevant and that increasingly sensitive tests may be picking up small emboli. The size and location of a clot or clots may matter when deciding on management. A risk-benefit evaluation can assist in deciding treatment.

              • Subspecialty:
              • Pediatric Orthopaedics

            Submuscular Plating of Pediatric Femur Fracture

            Currently, surgical management of pediatric femur fracture consists of intramedullary nailing with flexible nails or rigid trochanteric entry nails. Rigid trochanteric entry nails are the implant of choice for femoral fractures in adolescents, whereas titanium elastic nails are popular for the management of length-stable diaphyseal femoral fractures in school-age children. However, higher complication rates have been reported in children with length-unstable diaphyseal femoral fractures treated with titanium elastic nails. These complications may require unplanned surgery. Fracture shortening or angulation can lead to nail prominence or exposure that may require nail shortening or removal. Recently, submuscular plating has been found to be a successful alternative option for management of length-unstable femoral fractures in school-age children. Submuscular plating can also be used in older and/or heavier children who have a femoral canal that is too small to accommodate a rigid intramedullary nail.

                • Subspecialty:
                • Pediatric Orthopaedics

              Use of Negative-pressure Wound Therapy in Orthopaedic Trauma

              Negative-pressure wound therapy (NPWT) has become an important adjunct to the management of traumatic wounds and surgical incisions related to musculoskeletal trauma. On the battlefield, this adjunct therapy allows early wound management and safe aeromedical evacuation. NPWT mechanisms of action include stabilization of the wound environment, reduction of wound edema, improvement of tissue perfusion, and stimulation of cells at the wound surface. NPWT stimulates granulation tissue and angiogenesis and may improve the likelihood of primary closure and reduce the need for free tissue transfer. In addition, NPWT reduces the bacterial bioburden of wounds contaminated with gram-negative bacilli. However, an increased risk of colonization of gram-positive cocci (eg, Staphylococcus aureus) exists. Although NPWT facilitates wound management, further research is required to determine conclusively whether this modality is superior to other management options. Ongoing research will continue to define the indications for and benefits of NPWT as well as establish the role of combination therapy, in which NPWT is used with instillation of antibiotic solutions, placement of antibiotic-laden cement beads, or silver-impregnated sponges.

                  • Subspecialty:
                  • Trauma

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