Endstage arthritis following tibia plateau fractures: average 10-year follow-up.

BACKGROUND: Patients with tibial plateau fractures are believed to have an increased risk for posttraumatic arthritis that may require reconstructive surgery. The incidence of this problem is, however, unknown. We sought to determine the average 10-year incidence of posttraumatic arthritis necessitating reconstructive surgery following tibia plateau fractures. METHODS: We used data from our orthopedic trauma database to identify patients with operatively treated tibia plateau fractures. Their cases were cross-referenced with the data from our province's administrative health database and tracked overtime for the performance of reconstructive knee surgery. The average follow-up was 10 years. RESULTS: There were 311 tibial plateau fractures treated at our institution between 1987 and 1994. The 10-year Kaplan-Meier survival analysis for the primary outcome of endstage arthritis was 96%. Analysis of the secondary outcome measure, specifically surgeries for what was thought to be "minor arthritis," revealed a 10-year Kaplan-Meier survival of 87%. CONCLUSION: Our findings may be used to counsel patients who require surgical treatment of tibia plateau fractures about the long-term risk of requiring reconstructive knee surgery for endstage arthritis in the knee.

Pinning technique for shoulder fractures in adolescents: computer modelling of percutaneous pinning of proximal humeral fractures.

BACKGROUND: In the technique of percutaneous pinning of proximal humerus fractures, the appropriate entry site and trajectory of pins is unknown, especially in the adolescent population. We sought to determine the ideal entry site and trajectory of pins. METHODS: We used magnetic resonance images of nonfractured shoulders in conjunction with radiographs of shoulder fractures that were treated with closed reduction and pinning to construct 3-dimensional computer-generated models. We used engineering software to determine the ideal location of pins. We also conducted a literature review. RESULTS: The nonfractured adolescent shoulder has an articular surface diameter of 41.3 mm, articular surface thickness of 17.4 mm and neck shaft angle of 36 degrees. Although adolescents and adults have relatively similar shoulder skeletal anatomy, they suffer different types of fractures. In our study, 14 of 16 adolescents suffered Salter-Harris type II fractures. The ideal location for the lateral 2 pins in an anatomically reduced shoulder fracture is 4.4 cm and 8.0 cm from the proximal part of the humeral head directed at 21.2 degrees in the coronal plane relative to the humeral shaft. CONCLUSION: Operative management of proximal humerus fractures in adolescents requires knowledge distinct from that required for adult patients. This is the first study to examine the anatomy of the nonfractured proximal humerus in adolescents. This is also the first study to attempt to model the positioning of percutaneous proximal humerus pins.

A biomechanical study of conventional acetabular internal fracture fixation versus locking plate fixation.

BACKGROUND: Conventional internal fixation entails the use of an interfragmentary lag screw along with a plate. Not all acetabular fractures are amenable to the placement of an interfragmentary lag screw, and the fracture may be displaced during tightening of the interfragmentary lag screw. Locking plates are a possible solution. We sought to determine whether a locking plate construct can provide stability equivalent to that provided with a conventional construct for transverse acetabular fractures. METHODS: We used 5 paired fresh-frozen cadaveric acetabula. We fixed one side with the conventional technique and the other side with a locking plate. We subjected each fixation to a cyclic compressive force up to 500 cycles, followed by compressive force until failure. We monitored 3-dimensional motion of the fracture. RESULTS: The average fracture gap at 50 N compressive force after 500 loading cycles was 0.41 (standard deviation [SD] 0.49) mm for the conventional plate and lag screw construct compared with 0.76 (SD 0.62) mm for the locked plate construct (p = 0.46). The force to failure, as defined by 2 mm of fracture gap, was 848 (SD 805) N for the conventional plate and lag screw construct compared with 506 (SD 277) N for the locked plate fixation (p = 0.34). CONCLUSION: The locking plate construct is as strong as the conventional plate plus interfragmentary lag screw construct for fixing transverse acetabular fractures. Locking plates may improve management of acetabular fractures by eliminating the need for placement of an interfragmentary lag screw. Furthermore, they may be helpful in revision hip arthroplasty in patients with pelvic discontinuity.

Surgery for osteitis pubis.

BACKGROUND: Osteitis pubis is a rare and self-limited condition. Surgery may be necessary in 5%-10% of cases. The outcome after surgery for osteitis pubis is not known. METHODS: To determine the success of surgical intervention for osteitis pubis, we used a computerized data registry to identify patients (10 women [mean age 40 yr]) who underwent surgery for osteitis pubis. A retrospective chart review was carried out. We also searched the literature for all cases of osteitis pubis managed surgically and identified 73 cases. RESULTS: The 10 patients in our series had had symptoms for a mean of 4 years preoperatively. Onset of pain was insidious in 4 patients, it followed childbirth in 4 and it followed trauma in 2. Depending on the surgeon's preference, either a wedge resection of the symphysis pubis was performed or a symphysiodesis. At the latest follow-up (average 26 mo), although all patients had some improvement, only 6 of 10 patients were satisfied with the outcome. From the literature review, we identified 3 categories of patients with osteitis pubis: elite athletes, patients with postoperative or infectious osteitis pubis and the remainder, which would include the patients in our series. CONCLUSIONS: Four types of surgical intervention are described: curettage, arthrodesis, wedge resection and wide resection. The elite athletes respond well to curettage. Patients with osteitis pubis following urologic or gynecologic procedures or have a proven infection require surgery in roughly 50% of cases. The third group has an unpredictable outcome.

An unusual fracture of the talus in a snowboarder.

Fractures of the talus are uncommon. However, snow- boarding and skateboarding are 2 activities that are specifically associated with talus fractures. These patients sustain occult lateral talus process fractures that present as a severe ankle injury. The diagnosis is difficult because of subtle clinical and plain radiographic findings. Computed tomography is a very useful tool for the assessment of these injuries. Although the majority of these athletes have lateral sided talus fractures, there are variants. We present an unusual case of a displaced intra-articular fracture of the subtalar joint involving the middle articular facet of the talus with extension of the fracture into the talar head. This highlights the importance of carefully assessing snowboarders' "ankle injuries."

Retroacetabular osteolysis: when to operate?

Polyethylene liner exchange for retroacetabular osteolysis should be done before the shell becomes loose. The purpose of this study was to determine the radiographic quantity of osteolysis that will predict impending loosening of the cementless shell. Between 1992 and 2002, 46 cementless shells were revised at our institution for aseptic osteolysis. Radiographs and a computer-assisted technique were used to quantify osteolysis. Implant stability was confirmed intraoperatively. Of 26 stable and 20 loose shells, the average area of osteolysis on anteroposterior radiographs showed no significant difference, whereas lateral radiographs showed a difference. The percentage of shell circumference with associated osteolysis seen on anteroposterior and lateral radiographs showed a significant difference. Diagnostic criterion of 50% shell circumference associated with osteolysis on lateral films has a sensitivity of 0.84 and a specificity of 0.54, and on anteroposterior views, a sensitivity of 1.0 and a specificity 0.27 for predicting shell loosening. Percent of shell circumference with surrounding osteolysis seems to be more predictive of loosening than the area of osteolysis. When 50% of the shell circumference has osteolysis evident on anteroposterior or lateral radiographs, but preferably anteroposterior radiographs, liner exchange should be considered so that the exchange procedure is still possible, rather than allowing the osteolysis to increase and compromise shell fixation.

Revision total hip arthroplasty with use of a cemented femoral component. Results at a mean of ten years.

BACKGROUND: Revision of the femoral component of a total hip replacement with use of cement has been associated with early mechanical failure due to aseptic loosening. The purpose of the present study was to determine the long-term survival after revision of the femoral component with cement and to identify factors that were predictive of failure. METHODS: The results of 129 revision total hip arthroplasties that had been performed with use of a cemented femoral stem were reviewed to determine component survival. Ninety-seven hips that had been followed for a minimum of five years were included in survival analysis and tests of significance. Harris hip scores were used to quantify clinical outcomes. Clinical and surgical factors were analyzed to determine whether they were predictive of failure. RESULTS: The mean Harris hip score improved from 52 points preoperatively to 71 points at the time of the most recent follow-up (p < 0.001). The ten-year survival rate was 91% with rerevision of the femoral component because of aseptic loosening as the end point and 71% with mechanical failure as the end point. Patients who were more than sixty years old had greater long-term component survival and less pain than younger patients did (p < 0.05). A good-quality postoperative cement mantle was associated with better long-term radiographic signs of fixation (p < 0.001). Poor femoral bone quality was associated with an increased rate of rerevision for aseptic loosening (p = 0.021). CONCLUSIONS: Revision with use of a cemented femoral component remains an option for selected patients, with an acceptable ten-year survival rate and fair radiographic evidence of fixation. Our patients had acceptable clinical outcomes at ten years, and few had notable pain. The best results may be achieved in older patients (those who are sixty years old or more) with adequate bone stock who are managed with modern cementing techniques.

The dislocating hip: what to do, what to do.

Dislocation complicates between 1% and 3% of primary total hip arthroplasties (THAs) and 7% to 10% of revision procedures. Sixty percent of dislocations occur within the first 5 weeks. Closed reduction is successful in 67% of cases. If the hip keeps dislocating, revision surgery for instability is successful in only about 61% of patients. Many successful techniques have been described to deal with recurrent instability, including trochanteric advancement, modular component exchange, jumbo femoral heads, a bipolar or tripolar arthroplasty, or a constrained acetabular component. This article discusses the results of various surgical interventions and presents a treatment algorithm.

Patellar options in revision total knee arthroplasty.

There are numerous options that need to be considered by the surgeon at the time of revision total knee arthroplasty (TKA). One needs to consider the reason for the revision, the type of patella in place, and the length of time the patella has been in place. The surgeon also needs to consider the status of the patellar bone stock, the stability of the patellar component (well-fixed or loose), and the component type (cemented or metal-backed). Assuming that the existing prosthesis is not metal-backed and has minimal PE wear, then it is preferable to retain a well-fixed all-PE cemented patellar button. However, if the button is metal-backed, then it probably is best to remove the button and replace it with an all-PE domed patellar component. Assuming more than 8 mm of patellar bone stock is remaining, it usually is best to cement an all-PE dome-shaped patella. However, if less than 8 mm is remaining, then that patient can be left with a patelloplasty, recognizing that this individual is going to continue with a high likelihood of anterior knee pain, subluxation, and poor functional results. In that situation, it may be preferable to consider a bone stock augmentation.

Autologous osteoarticular transfer from the proximal tibiofibular joint to the scaphoid and lunate facets in the treatment of severe distal radial fractures: a report of two cases.

PURPOSE: This study was conducted to determine the appropriateness of using the articular cartilaginous surfaces of the proximal tibiofibular joint to resurface damaged distal radial articular surfaces and to assess the clinical results in the first 2 patients. METHOD: Cadaveric specimens of the facets of the proximal tibiofibular joints and distal radius were sized and compared. Two patients underwent transfer of a fibular facet. RESULTS: The surface area of each of the proximal tibiofibular facets were larger than either the scaphoid or lunate facets of the distal radius. The 2 patients had excellent clinical results with minimal donor morbidity. CONCLUSIONS: Use of the articular surfaces from the proximal tibiofibular joint to replace damaged distal radial facets is possible and can be accomplished with excellent results and minimal morbidity.