Michael D. Stover

Failure of Exchange Reamed Intramedullary Nails for Ununited Femoral Shaft Fractures

OBJECTIVE To determine the effectiveness of exchange reamed nails for treatment of aseptic femoral delayed unions and nonunions. DESIGN Retrospective chart review. PATIENTS Nineteen patients admitted to the Carolinas Medical Center Level I trauma center from 1990 to 1996 for repair of femoral shaft fracture nonunion following contemporary locked nailing performed at least six months previously. These patients showed no radiographic evidence of progression of fracture healing for three months and had clinical symptoms of nonunion. INTERVENTION Exchange reamed nails to treat ununited femoral shaft fracture. MAIN OUTCOME MEASUREMENTS Radiographic and clinical evidence of union of the fracture or of the necessity for additional procedures. RESULTS In 53 percent of the patients the secondary procedure resulted in fracture union, whereas in 47 percent, one or more additional procedures were required. Eight of the nine fractures that did not unite with exchange nailing united after a subsequent procedure (bone grafting, compression plating, or nail dynamization). Neither the type of nonunion, the location of the shaft fracture, the use of static versus dynamic cross-locking, nor the use of tobacco products was statistically predictive of the need for additional procedures. CONCLUSIONS Reevaluation of routine exchange nailing as the recommended treatment for aseptic femoral delayed union or nonunion may be required. A significant number of patients who undergo reamed exchange nailing will require additional procedures to achieve fracture healing.

Distal femoral fractures: current treatment, results and problems.

The evolution of treatment for supracondylar femoral fractures has sequentially addressed the difficulties of alignment, articular reduction, stabilization and fracture union. Adequate surgical stabilization and early motion diminished stiffness, while newer indirect techniques in handling periarticular tissues have greatly improved union rates. Indirect methods of reduction require an understanding of anatomy and deformity to avoid malalignment. The problems we currently face are fixation in osteoporotic bone or small distal articular segments.

Comparison of a Novel FiberWire-Button Construct versus Metallic Screw Fixation in a Syndesmotic Injury Model

Background: There is minimal experience with less rigid syndesmotic fixation devices which may approximate the normal distal tibio-fibular mechanics during healing. This study evaluates the ability of a FiberWire-button implant (Arthrex, Naples, FL) to maintain syndesmotic reduction as compared with a metallic screw. Methods: Ten matched fresh-frozen cadaveric ankle pairs with intact ligaments were tested (12.5 Nm external rotation force) to establish physiologic syndesmotic diastasis. The same force was applied to the ankles after sectioning of the syndesmotic and deltoid ligaments. Within the pairs, each limb was randomized to receive a FiberWire-button implant or a metallic screw (Synthes, Paoli, PA); the ankles were tested for syndesmotic diastasis with progressive external rotation force, from 2.5 Nm to 25 Nm (or failure). Results: There was no significant difference in diastasis amongst pairs with intact or sectioned syndesmosis (p = 0.64 and p = 0.80, respectively). There was a significantly greater diastasis in the FiberWire-button group at all external rotation loads (p < 0.0001). Nine of the ten pairs failed (all through fracture of the distal fibula). There were no hardware failures. The metallic screw group failed at a lower load (mean 15 Nm) compared to the FiberWire-button group (mean 18 Nm, p = 0.0004). The metallic screw group maintained syndesmotic reduction up to 5 Nm of force. Conclusions: The FiberWire-button was unable to maintain syndesmotic reduction of the ankles at any of the forces applied. The ankles fixed with the FiberWire-button demonstrated significantly greater widening of the syndesmosis compared to the screw, at all loads. Clinical Relevance: The FiberWire-button implant may not maintain adequate ankle syndesmotic reduction in the immediate post-operative period relative to a metallic screw.

A reliable method for intraoperative evaluation of syndesmotic reduction.

Objectives: To determine the accuracy of a technique for intraoperative assessment of syndesmotic reduction in ankle fractures. Design: Prospective, case series. Setting: University hospital. Patients/Participants: Eighteen consecutive patients with suspected syndesmotic injuries were enrolled between 2007 and 2009. The diagnosis of syndesmotic injury was based on static ankle radiographs. The study group consisted of 12 male and 6 female patients with an average age of 32 years (range 19–56 years). Intervention: All patients had mortise and talar dome lateral fluoroscopic images obtained of the uninjured ankle in the operating room. The injured ankle underwent operative reduction and provisional fixation using the uninjured ankle radiographs as a template for comparison. An intraoperative computed tomography (CT) scan was obtained to verify the syndesmotic reduction before syndesmotic fixation. If the reduction was not anatomic, the reduction was revised using fluoroscopy and the CT repeated. Main Outcome Measurements: Accuracy of syndesmotic reduction performed using fluoroscopy and confirmed by intraoperative CT scan. Results: Using the technique described, intraoperative CT confirmed anatomic reduction initially in 17 of the 18 fractures. The 1 case where CT did change the course of treatment, revision of fibular fracture reduction resulted in an anatomic reduction of the syndesmosis on repeat CT. Conclusions: Accurate evaluation of the syndesmotic reduction can be determined intraoperatively using comparison mortise and talar dome lateral fluoroscopic images. Direct visualization of the syndesmosis or CT may not be necessary to achieve an accurate reduction in these injuries.

The use of gravity or manual-stress radiographs in the assessment of supination-external rotation fractures of the ankle

Supination-external rotation (SER) fractures of the ankle may present with a medial ligamentous injury that is not apparent on the initial radiographs. A cadaver gravity-stress view has been described, but the manual-stress view is considered to be the examination of choice for the diagnosis of medial injuries. We prospectively compared the efficacy of these two examinations. We undertook both examinations in 29 patients with SER fractures. Of these, 16 (55%) were stress-positive, i.e. and had widening of the medial clear space of > 4 mm with a mean medial clear space of 6.09 mm (4.4 to 8.1) on gravity-stress and 5.81 mm (4.0 to 8.2) on manual-stress examination, and 13 patients (45%) were stress-negative with a mean medial clear space of 3.91 mm (3.3 to 5.1) and 3.61 mm (2.6 to 4.5) on examination of gravity- and manual-stress respectively. The mean absolute visual analgoue scale score for discomfort in the examination of gravity stress was 3.45 (1 to 6) and in the manual-stress procedure 6.14 (3 to 10). We have shown that examination of gravity-stress is as reliable and perceived as more comfortable than that of manual stress. We recommend using it as the initial diagnostic screening examination for the detection of occult medial ligamentous injuries in SER fractures of the ankle.

Complications Associated With Negative Pressure Reaming for Harvesting Autologous Bone Graft: A Case Series

A technical benefit of the reamer-irrigator-aspirator (RIA) system (Synthes, Paoli, PA) is the ability to harvest large volumes (40-90 cm3) of autogenous bone graft. Early evaluations of this technique have reported few problems, all of which were attributed to technical error. This case series reviews 6 RIA-associated complications including 4 fractures and their contributing risk factors. Cases were collected from 4 independent orthopaedic centers, and all patients underwent RIA bone graft harvesting in a lower extremity long bone injuries. In this population, 2 patients experienced acute RIA-associated events, necessitating an additional procedure or altered postoperative rehabilitation, whereas 4 patients fractured through their donor site in the early postoperative period. This series suggests that surgeons should (1) preoperatively assess cortical diameters at long bone harvest sites, (2) carefully monitor intraoperative reaming, and (3) avoid RIA bone graft harvesting in patients with a history of osteoporosis or osteopenia unless postharvest intramedullary stabilization is considered.

Prospective comparison of contrast-enhanced computed tomography versus magnetic resonance venography in the detection of occult deep pelvic vein thrombosis in patients with pelvic and acetabular fractures.

Objective To determine the rate of pelvic vein thrombosis following acetabular or pelvic fracture identified by enhanced computed tomography venography or magnetic resonance venography. Design Prospective evaluation of computed tomography venography and magnetic resonance venography in patients with pelvic and acetabular trauma as a screening tool for deep vein thrombosis. Setting Level I trauma center. Results Thirty patients with pelvic or acetabular fractures and who met the study criteria were prospectively screened with magnetic resonance venography and computed tomography venography to determine preoperative presence of pelvic venous thrombosis. Pelvic deep vein thrombosis was detected by computed tomography venography in two patients (7%) and by magnetic resonance venography in four patients (13%). Invasive selective pelvic venographies were performed on the five subjects who tested positive on either one or both screening tests. Only one computed tomography venography case was validated by invasive pelvic venography. The false-positive rate for computed tomography venography was 50%, and the false-positive rate for magnetic resonance venography was 100%. Conclusions We cannot recommend the sole use of either computed tomography venography or magnetic resonance venography to screen and direct the treatment of asymptomatic thrombi in patients with fracture of the pelvic ring because of the high false positive rates. If these studies are used as screening tools, confirmation of the presence of thrombosis with selective venography should be performed prior to initiating invasive treatment with a vena cava filter. Clinical decisions based solely on one of these imaging techniques may result in inappropriate aggressive treatment due to the high false-positive rate.

Late Posterior Instability of the Pelvis after Resection of the Symphysis Pubis for the Treatment of Osteitis Pubis. A Report of Two Cases

Inflammation of the symphysis pubis, commonly known as osteitis pubis, is a painful disorder of uncertain etiology. The onset of osteitis pubis has frequently been reported after urological or gynecological procedures and is associated with a number of conditions, including trauma, rheumatological disorders, pregnancy, and parturition3,6,8,9,12,15. In most patients, symptoms of osteitis pubis resolve spontaneously; however, a small number of patients have pain that persists indefinitely. Resection of the symphysis has been recommended for the treatment of osteitis pubis that is unresponsive to non-operative management. Several authors have reported early relief of symptoms with this procedure; however, the long-term effect of resection of the symphysis on the integrity of the ligaments of the sacroiliac joint is of concern3,6,14. We report on two patients in whom debilitating posterior instability of the pelvis developed and necessitated operative stabilization twelve and eighteen years after wedge resection of the symphysis pubis for the treatment of osteitis pubis. CASE 1. A forty-two-year-old woman was involved in a skiing accident in 1978. At the time of the injury, the patient noted immediate pain in the area of the symphysis pubis. The pain gradually increased over the next six weeks, prompting her to seek medical attention. Osteitis pubis was subsequently diagnosed, but the patient was not offered any non-operative treatment. One month after she was seen, she was managed with wedge resection of the symphysis pubis, including the entire symphyseal joint and a total of fifteen millimeters of bone. Initially, the symptoms decreased; however, over the next five years the patient noted the onset of low-back pain centered over the sacroiliac joints. The symptoms were managed non-operatively with repeated injections of corticosteroids and oral administration of non-steroidal anti-inflammatory medications, …

Does screw configuration affect subtrochanteric fracture after femoral neck fixation

A subtrochanteric femur fracture after cannulated screw fixation of a femoral neck fracture is a devastating complication. We hypothesized that an apex-distal screw orientation would tolerate higher loads to subtrochanteric fracture. Human cadaveric femora were instrumented with three cannulated screws in either an apex-distal or an apex-proximal configuration. Specimens were loaded along the mechanical axis to failure creating a subtrochanteric femur fracture. Ultimate load to failure and the effect of bone density on load to failure were compared between groups. There was a greater load to failure in the apex-distal group compared with the apex-proximal group. The mean force to fracture in the apex-distal group (11,330 N; standard deviation = 3151 N) was greater than the mean force to fracture in the apex-proximal group (7795 N; standard deviation = 3194 N). Previous investigations have shown improved femoral neck fixation with an apex-distal configuration, but none has examined the relationship between screw orientation and subtrochanteric fractures. Our observations support the use of an apex-distal configuration for cannulated screw fixation of femoral neck fractures.

Morphologic characteristics of acetabular dysplasia in proximal femoral focal deficiency

A retrospective radiographic analysis of the acetabulum of 13 patients (14 hips) with proximal femoral focal deficiency (PFFD), clinically classified into Gillespie and Torode type 1, was performed to better understand its morphologic features at maturity. The version of the proximal part of the acetabulum was determined quantitatively and qualitatively. All 14 hips showed residual or borderline acetabular dysplasia with a mean lateral centre–edge angle of −1.5° and an acetabular index of 30°. The acetabular dome was retroverted in all hips and averaged −24°. Acetabular deficiency compared with the opposite side, while not present with respect to the anterior wall, averaged 12% with respect to the posterior wall. Dysplasia associated with type 1 PFFD is therefore fundamentally different from that seen in developmental residual hip dysplasia. Clinically, despite radiographic evidence of dysplasia, 57% were without clinical manifestations of hip pathology. This may be due to a number of factors including age of last radiograph, severity of dysplasia, and the decreased functional demand placed on the hip in some individuals with associated malformations. For the symptomatic hip, the posterior insufficiency and relative retroversion of the acetabular dome should be taken into consideration in planning reorientation procedures. This can help to prevent problems of persistent subluxation or acetabulo-femoral impingement following reconstruction.