Reduced Incidence of Perioperative Periprosthetic Fractures Using Hybrid Rasp-Impaction Broaching Over Impaction Broaching When Using the Direct Anterior Approach for Total Hip Arthroplasty.

Background: A not infrequent complication encountered with the direct anterior approach is perioperative fracture. The purpose of this study was to compare the incidence of perioperative fractures using a hybrid rasp-impaction broach vs an impaction broach for a similarly designed stem. Methods: Retrospective study of 798 primary total hip replacements by 1 surgeon performed using noncollared dual tapered femoral stems, including 457 implanted using hybrid rasp-impaction broaching and 341 implanted using impaction broaching. Intraoperative and 90-day postoperative fractures were identified in each group. Bivariate tests and multivariate regression analysis were used to compare the 2 groups. Results: There were 33 (4.1%) fractures in the sample, 13 (2.8%) with hybrid rasp-impaction broaching and 20 (5.8%) with impaction broaching (P = .034). Three (0.7%) intraoperative fractures occurred with hybrid rasp-impaction broaching and 12 (3.5%) with impaction broaching (P = .003). Five (1.1%) total calcar fractures occurred with hybrid rasp-impaction broaching and 11 (3.2%) with impaction broaching (P = .034). Intraoperative calcar fractures occurred with 1 (0.2%) hybrid rasp-impaction broaching and 6 (1.8%) impaction broaching (P = .021). In multivariate analyses, hybrid rasp-impaction broaching had a statistically lower odds ratio (OR) for total fracture (OR 0.45 [0.22 to 0.93]); total intraoperative fracture (OR 0.17 [0.05 to 0.60]); total calcar fracture (OR 0.33 [0.11 to 0.97]); intraoperative calcar fracture (OR 0.11 [0.01 to 0.98]); and rate of readmission (OR 0.27 [0.10 to 0.78]). Conclusion: The use of a hybrid rasp-impaction broach compared with impaction broach led to a reduced incidence of periprosthetic fractures when using a dual tapered stem through the direct anterior approach.

Perioperative Complications Stratified by Body Mass Index for the Direct Anterior Approach to Total Hip Arthroplasty.

BACKGROUND: Previous studies have addressed the increased risk of perioperative complications in the obese and morbidly obese populations undergoing total hip arthroplasty. Over the last 15 years, the direct anterior approach has increased in popularity. The purpose of this study is to compare the 90-day perioperative complication rate of total hip arthroplasty performed through the direct anterior approach stratified by body mass index (BMI). METHODS: Perioperative complications both intraoperative and up to 90 days postoperative were identified in a case series of 1808 primary total hip arthroplasties performed through a direct anterior approach. The patients were stratified according to BMI. Demographics of age, side, sex, and American Society of Anesthesiologists score were recorded. Medical and surgical complications including National Surgical Quality Improvement Program complications, length of stay, reoperation rate, readmission rate, and length of operation were recorded. Bivariate analysis and analysis of variance were performed. RESULTS: Morbidly obese patients (BMI > 40) demonstrated increased American Society of Anesthesiologists scores, increased surgical times with statistically significant increase in number of patients with surgical complications, National Surgical Quality Improvement Program complications, deep infection, and wound breakdown. Grading the severity of complications also demonstrated the morbidly obese had a higher risk of experiencing more severe complications. Underweight patients (BMI < 18.5) demonstrated a statistically significant readmission rate. CONCLUSION: In stratifying patients undergoing the direct anterior approach for total hip arthroplasty by BMI, a greater rate of surgical complications both in number and in severity occurs with the morbidly obese undergoing total hip arthroplasty through a direct anterior approach.

Isolated Greater Trochanteric Fracture and the Direct Anterior Approach Using a Fracture Table.

BACKGROUND: To identify the incidence, contributing factors, and outcomes of perioperative greater trochanter fractures associated with the direct anterior approach. METHODS: This is a retrospective analyses of 1401 primary THAs. Age, side, height, weight, body mass index, preoperative ambulatory status, discharge status, and hospital length of stay were identified. Radiographs were evaluated for femoral neck angle, femoral neck cut ratio (FNCR), and DORR ratio. Bivariate and logistic regression analyses were performed. RESULTS: Thirty-one hips sustained isolated greater trochanter fractures (2.2%). Multivariate analyses identified worse preoperative ambulatory status, diagnosis of slipped capital femoral epiphysis or rheumatoid arthritis, lower FNCR and greater DORR ratio as statistically significant predictors for fracture. Four intraoperative fractures underwent fixation. All postoperative fractures were treated nonoperatively. Thirty fractures healed with 1 nonunion. CONCLUSION: Worse preoperative ambulatory status, diagnosis of slipped capital femoral epiphysis or rheumatoid arthritis, greater DORR ratio, and lower FNCR were associated with increased risk of fracture. Hips with fractures had longer length of stay. Nonoperative treatment was uniformly successful.

The learning curve for the direct anterior approach for total hip arthroplasty: a single surgeon's first 500 cases.

BACKGROUND: Concerns arise over the early complications encountered during the learning curve for the direct anterior approach for total hip arthroplasty.The purpose of this study is to examine the learning experience of a single surgeon in adapting this approach. METHODS: The 1st 500 primary total hip arthroplasties are reviewed. The patients were evaluated out to 3 months. Rates of major complications, reoperations, periprosthetic fractures, heterotopic ossification, leg length discrepancies and lateral femoral cutaneous nerve deficits were identified for each of 100 patients. RESULTS: The major complication rate decreased from 5% to 2% throughout the series. Reoperation rates fluctuated from 2% in the 1st 100 cases to 3% in the 4th 100 cases to 1% in the 5th 100 cases. The periprosthetic fracture rate decreased from 9% to 2%. CONCLUSIONS: The incidence of heterotopic ossification declines throughout the series and is attributed to changes in irrigation technique and quantity. The incidence of major complications decreases with increasing experience. The most dramatic improvements occur after the 1st group of 100 cases.

Risk Factors for Perioperative Femoral Fractures: Cementless Femoral Implants and the Direct Anterior Approach Using a Fracture Table.

BACKGROUND: With the increased popularity of the direct anterior approach, the issue of periprosthetic femur fractures has come into focus. The purpose of this article is to identify patient- and procedure-related characteristics that are associated with periprosthetic femur fractures in cementless total hip arthroplasties performed through a direct anterior approach using a fracture table. METHODS: Five hundred primary total hip arthroplasties performed using cementless femoral implants through a direct anterior approach using a fracture table were evaluated for characteristics associated with perioperative prosthetic femur fracture within the first 3 months of surgery. RESULTS: Twenty-three hips (4.6%) incurred fractures, 13 (2.6%) intraoperative and 10 (2.0%) postoperative. Bivariate analyses demonstrated females and a body mass index (BMI) >40 with a higher risk of fractures overall and postoperative fractures. A significant difference in DORR ratios was seen in patients with intraoperative fractures and a significant difference seen with implant sizes in patients with postoperative fractures. Multivariable regression analyses demonstrated an increased risk of postoperative fracture with a BMI >40. As the DORR ratio and implant size increased, there was a reduced odds of intraoperative fracture. CONCLUSION: Concern for periprosthetic femur fractures using the direct anterior approach for total hip arthroplasty is high in female patients and in patients with morbid obesity (BMI >40), small DORR ratio, or small implant size.

Recorrection Osteotomies and Total Knee Arthroplasties After Failed Bilateral High Tibial Osteotomies.

This article reports the case of a 58-year-old man with failed bilateral opening wedge high tibial osteotomies. Because of excessive valgus deformities, each total knee arthroplasty (TKA) was combined with a recorrection osteotomy. TKAs were performed consecutively. Recorrection osteotomy using a long-stemmed tibial component and a derotation plate corrected the valgus malalignment and maintained native ligament stability in each posterior cruciate ligament-retaining TKA.

Primary meniscal-bearing knee replacements: 8- to 15-year followup.

This study presents the survivorship data of a consecutive series of primary meniscal-bearing total knee replacements at one institution at 8 to 15 years followup. We reviewed 125 meniscal-bearing knee replacements in 93 patients at a minimum followup of 96 months (mean, 130 months; range, 96-191 months). The tibial and femoral components were cemented in 71 knees; uncemented femurs and tibias were used in 48 knees; and cemented tibias and uncemented femurs were used in six knees. One patient was lost to followup. Seventeen knees failed, three as a result of infection. Five knees were revised for loose tibial components and one for a loose femoral component. A second femoral component was identified as radiographically loose. All the loose components were uncemented. Five knees had reoperation for fractured bearings and one for a dislocated bearing. This knee was later rerevised for a loose uncemented tibia. One knee was revised for instability and a second knee was identified as grossly unstable but not revised. Kaplan-Meier survival analysis showed survivorship of approximately 90% at 9 years, which decreased to 71% at 15 years. Uncemented components had an increased aseptic loosening rate compared with cemented components. Meniscal-bearing replacements with cement fixation appeared successful, although bearing fracture seems to be a predominant failure mode at long-term followup.

Intertrochanteric osteotomy using a dynamic hip screw for femoral neck nonunion.

The dynamic hip screw, which is routinely used for intertrochanteric hip fractures, also provides a technically simple means of fixation for intertrochanteric valgus osteotomies in the treatment of femoral neck nonunions. Eight patients underwent intertrochanteric valgus osteotomy for femoral neck nonunion using a dynamic hip screw for fixation. One patient died 4 months postoperatively of causes unrelated to the procedure. The remaining 7 patients were followed for an average of 24 months postoperatively. The nonunion healed in all 7 cases. The average angle of the fracture plane decreased from 68 degrees to 41 degrees. All the hip fractures were classified as Pauwels type III preoperatively and Pauwels type II postoperatively. The average Harris Hip Score increased from 24 to 73. On radiographic review, no cases of osteonecrosis were identified postoperatively.

Surveillance venous duplex is not clinically useful after total joint arthroplasty when effective deep venous thrombosis prophylaxis is used.

The early detection of deep venous thrombosis (DVT) and treatment with systemic anticoagulation to prevent pulmonary embolism (PE) are essential in the management of patients undergoing total joint arthroplasty (TJA). However, improvements in prophylactic measures have significantly decreased the occurrence of DVT in these patients. The purpose of this study was to determine whether routine postoperative duplex surveillance for DVT remains clinically useful. The medical records of all patients undergoing total knee or total hip arthroplasty between October 1997 and January 2002 at a University Hospital and its Veterans Affairs (VA) affiliate were reviewed. The type of operation and occurrence of complications (e.g., DVT, PE, and hemorrhage) were noted. All patients were treated postoperatively with both enoxaparin 30 mg b.i.d. and bilateral lower extremity sequential compression devices (SCDs). A venous duplex scan was performed prior to discharge. Three hundred ninety-eight patients underwent 441 TJAs for 149 hips and 292 knees. The average age was 65 years (range, 23-95). Venous duplex scans were performed within 1 week (median, 4 days) of operation. Initial inpatient scans revealed acute, ipsilateral DVT in five patients (1.3%). Three patients experienced documented PE-one as an inpatient and two after hospital discharge; both outpatients had negative inhospital duplex scans. One of the 398 patients did not have a duplex scan as an inpatient and returned 6 weeks later with a popliteal DVT. Complications included one upper gastrointestinal hemorrhage, and one patient died postoperatively of unknown causes. These data demonstrate that routine postoperative venous duplex scans rarely found DVT (5 of 398 patients) after TJA when effective prophylaxis was used. Furthermore, surveillance scanning did not enable reliable prediction of PE. Therefore, we conclude that postoperative inpatient surveillance duplex scans for DVT provide very minimal benefit and that a routine screening program is not clinically useful for patients managed with effective DVT prophylaxis.

Endovascular repair of external iliac artery occlusion after hip prosthesis migration.

PURPOSE: To report emergent endovascular intervention to restore lower extremity arterial patency after migration of a hip prosthesis caused thrombosis of the external iliac artery (EIA). CASE REPORT: Nine months following left hip revision arthroplasty, a 66-year-old woman presented to the Emergency Department with the complaints of an acutely painful left lower extremity for over 6 hours. Imaging showed the metallic acetabular portion of the hip prosthesis in the iliac fossa, with severe external compression of the EIA. After thrombolysis to remove clot from the EIA, an 8x60-mm self-expanding Smart stent was deployed in the left EIA from a contralateral access. The procedure was successful, and the patient was discharged. An infected wound from a compartment fasciotomy delayed revision of the hip prosthesis. Nine weeks after stenting, the patient returned with a cold, pulseless left limb; a femorofemoral bypass was constructed to restore perfusion. CONCLUSIONS: While stent placement restored flow for 9 weeks after the initial ischemic event, the recurrent thrombosis could have been prevented by earlier revision of the migrated prosthesis.

Biomechanical superiority of plate fixation for proximal tibial osteotomy.

Proximal tibial osteotomies require secure and durable fixation to allow early range of motion; however, biomechanical data comparing commonly used fixation methods are lacking. The current study was done to quantify the dynamic biomechanical performance of blade staple fixation and plate fixation of simulated proximal tibial osteotomies. A 15 degrees proximal tibial osteotomy was done on each of 18 synthetic adult composite tibias. Blade staples were used as the means of fixation in nine tibias; plate fixation was used in the remaining nine tibias. The specimens were stressed cyclically in sinusoidal loading whose peak compression and tension loads imitate those measured during normal gait. Device performance was quantified by measuring displacement at the osteotomy site and the number of cycles to failure. Plate fixation had a greater fatigue life than staples (eight plates surviving past 200,000 cycles versus one blade staple) and showed a trend toward less displacement (0.69 mm versus 0.97 mm). Plate fixation of proximal tibial osteotomies offers better fixation and dynamic mechanical performance than blade staples.

Athletic activity after total joint replacement.

Total hip and knee replacement surgery is a successful treatment for the arthritic hip and knee ensuring proven pain relief and return of function. Younger, more active patients who have greater expectations and higher demands are receiving hip and knee replacements. With current surgical techniques and implant designs, athletic participation should be limited to low impact, low demand, and low duration activity. Future advancesin bearing surfaces may allow for higher demand activities.

Press-fit metal-backed rotating patella: seven- to 14-year followup.

A consecutive series of 80 patients with 110 press-fit metal-backed rotating platform patella resurfacing surgeries were reviewed at an average of 107 months followup (range, 84-167 months). Twenty-eight patients died before followup. Fifty-two patients (70 patellae) were available for clinical and radiographic followups. One patella was revised for failure of the patella component. Four patellae were revised along with revision of the knee replacement. One patella realignment procedure was done for recurrent subluxation of the patella. There were no patellar dislocations in this series, no patella fractures, and no disruption of the quadriceps tendon or infrapatellar ligament. Six patellae had subluxation seen on postoperative radiographs. The incidence of patellar tilt greater than 5 degrees was 13%. No patellae were considered radiographically loose. The incidence of radiolucencies was 37%. Subsidence of the component superiorly was identified in 39% of the patellae, and inferiorly in 36% of the patellae. Of the 49 patients (67 knees) returning for followup, 70% of the knees were rated as excellent, 10% were rated good, 15% were rated fair, and 5% were rated poor. Press-fit metal-backed patella provided good component durability with only one revision because of component failure. Radiographic analyses showed a high incidence of subsidence associated with good clinical results.

Intraoperative frozen section analysis in revision total joint arthroplasty.

A prospective study of the sensitivity, specificity, and predictive values for frozen sections against cultures obtained at the time of revision total joint replacement was done. One hundred twenty-one revision total joint replacements were done in 92 men and 29 women. A positive frozen section with more than 10 polymorphonuclear leukocytes per high power field was compared with the intraoperative cultures. Twenty-one patients who had revision surgery had greater than 10 polymorphonuclear leukocytes per high power field. Of these, 14 patients had positive cultures. The remaining 100 patients had less than 10 polymorphonuclear leukocytes per high power field, but seven had positive cultures. Statistical analysis of frozen sections for all total joint arthroplasties revealed a 67% sensitivity, 93% specificity, 67% positive predictive value, and 93% negative predictive value. Analysis of frozen sections for total hip arthroplasties revealed a 45% sensitivity, 92% specificity, 55% positive predictive value, and 88% negative predictive value. Analysis for total knee arthroplasties revealed 100% sensitivity, 96% specificity, 82% positive predictive value, and 100% negative predictive value. Comparisons of sensitivity, positive predictive value, and negative predictive value between total knee arthroplasty and total hip arthroplasty were significant. The results indicate that the use of intraoperative frozen section analysis with greater than 10 polymorphonuclear leukocytes per high power field as an indication of infection lacks the positive predictive value and sensitivity for accurate determination of prosthetic infection at the time of revision total hip arthroplasty. Frozen sections have an acceptable sensitivity and positive predictive value in total knee arthroplasty. The results of the current study show the limitation of using frozen sections as a diagnostic test for infection in revision total hip arthroplasty.