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.

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.

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.

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.

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.

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.

Low contact stress mobile bearing total knee arthroplasty: results at 5 to 13 years

A total of 139 mobile bearing knee arthroplasties in 104 patients were evaluated at a mean follow-up of 7.8 years (range, 5-13 years). There were 80 cemented knees, 50 uncemented, and 9 hybrid (cemented tibia, uncemented femur). Ten knees were revised. Four knees were revised for aseptic loosening of an uncemented tibial component, and 1 knee was revised for loosening of an uncemented femoral component. One knee was revised for a recurrent dislocating bearing, and 1 knee was revised for instability. No mechanical loosening occurred in the cemented components. Three knee arthroplasties were revised for infection. A total of 66 patients (92 knees) were evaluated clinically and radiographically. Radiographic evaluation showed a 27% incidence of radiolucent lines for the femur and a 31% incidence of radiolucent lines for the tibia. No components were considered radiographically loose. The survivorship of mobile bearing knee arthroplasties was 93% at an average follow-up of 7.8 years. Aseptic loosening was statistically higher in uncemented components (P=.0051).

Open reduction internal fixation after displacement of a previously nondisplaced acromial fracture in a multiply injured patient: case report and review of literature

SUMMARY

A twenty-eight-year-old multiple trauma patient had a nondisplaced acromion fracture that was not detected until after it had displaced. Open reduction internal fixation was performed without complication and the patient achieved excellent shoulder abduction strength. Nondisplaced acromion fractures may displace if not protected. Open reduction internal fixation of displaced acromion fractures should be considered if deltoid muscle strength is important to the patient.

Noncemented Cathcart elliptical head endoprosthesis for displaced femoral neck fractures

A total of 93 patients (95 hips) undergoing unipolar noncemented elliptical head endoprosthetic replacement for an acute displaced femoral neck fracture were reviewed clinically and radiographically at an average follow-up of 28 months. The 12-month mortality rate was 22%. The medical complication rate was 15%, and the surgical complication rate was 19%. At most recent follow-up, 66% of patients used an assist device for ambulation or were nonambulatory. Of patients, 64% required full-time nursing care. Radiographically, subsidence of the component was identified in 66% of the hips and acetabular erosion in 29%. More than half of these patients had complaints of either thigh or groin pain. Hips with evidence of subsidence had a statistically significant greater length of follow-up (36 months) compared with hips that did not show subsidence (18 months; P = .014). Noncemented unipolar replacement for displaced femoral neck fractures is an accepted form of treatment. In this group of predominantly male patients, noncemented elliptical head unipolar replacement was associated with a high medical and surgical complication rate as well as poor clinical and radiographic results.

Late arthroscopic debridement of metal fragments and synovectomy after penetrating knee joint injury by low-velocity missile: a report of two cases

Retained metal debris from intraarticular missile injury to the knee may produce mechanical symptoms and synovitis. Arthroscopic debridement and thorough synovectomy can relieve symptoms and allow early return of function.

Radiographic analysis of low contact stress meniscal bearing total knee replacements

BACKGROUND

Meniscal bearing total knee replacements were developed to decrease the contact stresses on polyethylene and to reduce polyethylene wear. The kinematics of meniscal bearing knee replacements is poorly understood. The present study was designed to evaluate, with radiographic analyses, the motion of the meniscal bearings and the femoral rollback of the Low Contact Stress meniscal bearing knee replacement during knee flexion.

METHODS

Eighty-one Low Contact Stress meniscal bearing total knee replacements in seventy-six male patients were assessed on fluoroscopically centered lateral radiographs made with the knee in full extension and in full flexion at an average of six years (range, twenty-four to 147 months) after the operation. The distance and direction of motion of the meniscal bearings and the center contact position of the femoral condyles were measured. Knee evaluations were performed with use of the Knee Society rating system.

RESULTS

The average range of motion of the knees, measured on lateral radiographs, was 90 degrees (range, 45 degrees to 136 degrees). As they moved from terminal extension to terminal flexion, thirty-nine knees (48%) exhibited anterior motion of both bearings and sixteen (20%) demonstrated posterior motion of both bearings. Ten knees (12%) had reciprocal motion of the two bearings (one bearing moving anteriorly and one bearing moving posteriorly) with flexion, nine knees (11%) had motion of only one bearing, and seven knees (9%) had no motion of either bearing. When moving from full extension to full flexion, eighteen knees (22%) demonstrated femoral rollback, six knees (7%) showed no change in the position of femoral contact, and fifty-seven knees (70%) exhibited anterior sliding of the femoral condyles. Flexion of the knees demonstrating femoral rollback averaged 104 degrees (range, 76 degrees to 128 degrees), and flexion of the knees demonstrating anterior sliding averaged 94 degrees (range, 45 degrees to 125 degrees). The difference was significant (p = 0.03). According to the Knee Society rating system, the average clinical score for the entire group was 76 points (range, 27 to 100 points) and the average functional score for the entire group was 72 points (range, 30 to 100 points). The average clinical score was 79 points (range, 27 to 98 points) for the knees that exhibited anterior sliding of the femoral condyles and 87 points (range, 52 to 100 points) for those exhibiting femoral rollback (p = 0.09). The average functional scores were 64 points (range, 30 to 100 points) and 72 points (range, 45 to 100 points), respectively (p = 0.15).

CONCLUSIONS

Radiographic analysis of meniscal bearing total knee replacements demonstrated an average anterior motion of both the medial and the lateral meniscal bearing of 4.7 mm (range, 1 to 14 mm) in thirty-nine knees (48%) as they moved from terminal extension to terminal flexion. Sixty-three knees (78%) demonstrated no femoral rollback as they were flexed. Knees with anterior sliding of the condyles had a significantly smaller average range of flexion (p = 0.03) and a lower average Knee Society score than did knees demonstrating femoral rollback. We believe that lack of rollback indicates a functional insufficiency of the posterior cruciate ligament.

The iliolumbar ligament: three-dimensional volume imaging and computer reformatting by magnetic resonance: a technical note

STUDY DESIGN

An assessment of magnetic resonance imaging techniques of the iliolumbar ligament.

OBJECTIVES

To identify a technique to better image the iliolumbar ligament.

SUMMARY OF BACKGROUND DATA

The iliolumbar ligament plays an important role in providing lumbosacral stability. Two-dimensional magnetic resonance imaging of the lumbar spine only provides a fragmented representation of the ligament.

METHODS

A two-part study was performed. In the first part, three cadaver pelvi were dissected, and the individual bands of the iliolumbar ligament were identified. Computer reformatting of magnetic resonance three-dimensional volume images then were performed, correlating the structural characteristics of the iliolumbar ligament to its magnetic resonance image. In the second part of the study, the lumbosacral region of three groups of patients were evaluated. Group I was studied with routine magnetic resonance imaging techniques of the intervertebral disc regions. Group II was studied with routine contiguous axial magnetic resonance imaging of the lumbosacral spine. Group III was studied with computer reformatting of three-dimensional volume images of the lumbosacral spine.

RESULTS

Accurate imaging of the iliolumbar ligament of cadaver specimens was achieved with three-dimensional volume imaging and computer reformatting. Routine imaging of the intervertebral disc region as well as contiguous axial imaging of the spine depicted only limited segments of the iliolumbar ligament. Three-dimensional volume imaging and computer reformatting allowed precise imaging of the iliolumbar ligament in all patients, demonstrating the ligament orientation as well as length, width, and depth.

CONCLUSION

Only images of the iliolumbar ligament obtained through computer reformatting of three-dimensional volume averaging from L3 to the sacral ala correlated with the ligament's structural characteristics.

Results of a method of leg-length equalization for patients undergoing primary total hip replacement

The postoperative leg-length discrepancy was determined radiographically for a consecutive series of 351 patients (408 hips) who underwent bilateral or unilateral primary total hip replacement using a single method of leg-length equalization by preoperative planning with overlay templates. The method of equalization was performed by a measurement of the femoral head and neck segment to be resected from a reference point at the superior aspect of the dislocated femoral head. The amount of femoral bone resected was determined preoperatively by determining the dimensions of the acetabular component thickness and the femoral component head and neck height that would be replacing this resected bone and adjusting this distance for any preexisting leg-length discrepancy. Using this leg-length equalization method, the length of the modular femoral head neck was chosen preoperatively, rather than using soft tissue tension across the prosthetic hip joint to determine whether the leg lengths were equal. Postoperative leg lengths were determined radiologically from a measurement from the acetabular teardrop to the lesser trochanter. Ninety-seven percent of the patients had a postoperative leg-length discrepancy that was less than 1 cm, and 86% had a leg-length difference that was 6 mm (1/4 inch) or less. The average postoperative discrepancy for these 351 patients was 1 mm.

The use of femoral intramedullary nailing as an interim or salvage technique during complicated total hip replacement

When performing a revision total hip replacement complicated by infection, severe osteolysis, comminuted periprosthetic fracture, and/or extensive bone loss, a single-stage procedure may not be feasible. This study reports four cases of femoral intramedullary nailing as an interim or salvage technique during complicated total hip replacement. This reconstruction provides axial and rotational stability of the femur while maintaining femoral alignment. Furthermore, this reconstruction facilitates early mobilization and rehabilitation of the patient. This interim reconstruction can be converted to a revision total hip replacement at a later time. Alternatively, the stabilized resection arthroplasty may serve as a salvage technique if further reconstruction is not indicated.

Complex primary and revision total knee arthroplasty using the condylar constrained prosthesis: an average 5-year follow-up

The condylar constrained total knee arthroplasty was performed on 29 patients undergoing 33 procedures and were reviewed clinically and radiographically at an average follow-up of 5 years (range, 2-10 years). There were 21 women and 8 men. The average age at the time of surgery was 70 years (range, 32-84). Of the 16 knees that were revision total knee arthroplasties, 8 had a previous infected total knee arthroplasty, and 17 knees had severe deformities requiring the use of the condylar constrained prosthesis. The patients were rated according to the Knee Society clinical and radiological evaluation protocol. Measurements of femoral and tibial component position were obtained as well as femoral tibial angle, patella position, and cement bone radiolucencies. All clinical measurements were made by an independent physical therapist. Clinical results revealed an improvement from an average preoperative knee score of 38 points to an average postoperative score of 86 points. The clinical results for 19 (58%) knees were excellent, 8 (24%) had a good result, 1 (3%) was fair, 2 (6%) were poor, and 3 (9%) were failures. The patients' average functional levels increased from 24 to 58. The final average flexion was 96 degrees. Three knees have been revised (9%). One was revised for recurrent infection, one for periprosthetic fracture, and one for mechanical loosening of the tibial component. There were no other knees with evidence of radiologic loosening. We conclude that the condylar constrained total knee prosthesis provides an acceptable solution for revision and complex primary total knee replacements at an intermediate follow-up term of 5 years.

Preoperative duplex ultrasonography evaluation for deep vein thrombosis in hip and knee arthroplasty patients

We performed preoperative and postoperative duplex ultrasonography examinations on both lower extremities in 128 patients undergoing 146 hip and knee reconstructive procedures. The results of the examinations were reviewed by an independent radiologist who specializes in these studies. Three of the 128 patients (146 procedures; 2.1%) had evidence of a deep venous thrombosis or other venous abnormality before surgery. Three additional patients developed a deep venous thrombosis after surgery, despite mechanical and pharmacologic prophylaxis. We have discontinued performing preoperative duplex ultrasonography prior to primary, uncomplicated total joint replacement of the lower extremities. We continue to perform duplex ultrasonography before surgery in patients at high risk, with a history of deep venous thrombosis or phlebitic syndrome, and in those who have previously had major surgery on the lower extremities.

Tibiotalar contact area. Contribution of posterior malleolus and deltoid ligament

Sixteen fresh ankle specimens were tested under physiologic loads to evaluate the effect on the tibiotalar contact area of increasing-size posterior malleolar fracture fragments and disruption of the deltoid ligament. The tibiotalar joint was maintained in a neutral position, and contact areas were recorded on pressure sensitive film. Posterior malleolar fracture fragments of 25%, 33%, and 50% as visualized on lateral radiographs were created. The deltoid ligament was sectioned after the final fracture fragment was made. There was a corresponding decrease of 4%, 13%, and 22% in tibiotalar contact area with the increasingly larger fracture fragments. The final disruption of the deltoid ligament did not alter the contact area. Statistical analyses using Student's t-test showed a statistically significant decrease in tibiotalar contact area in the samples with a fracture fragment of 33% and 50% involvement of the joint as compared with the control samples. Transection of the deltoid ligament produced no statistically significant further change in contact area. Displaced posterior malleolus fractures produce a significant decrease in contact area with 33% or greater involvement of the joint, which may predispose the tibiotalar joint to degenerative changes that should be lessened by anatomic reduction and internal fixation. Disruption of the deltoid ligament does not appear to alter contact area further, supporting the concept of repair as optional.

Reconstructive amputation after grade IIIC open tibial fracture. One method of preserving residual limb length

A high percentage of patients with grade IIIC open tibial fractures eventually undergo amputation. Maintaining an adequate residual limb length is advantageous with regard to biomechanics, energy expenditure, and prosthetic fitting. This case report presents new considerations for maintaining residual limb length in the presence of comminuted proximal tibial fractures. These considerations include (a) using an autogenous fibular strut graft for stabilizing the reconstructed residual limb and (b) determining the level of amputation based on soft-tissue integrity rather than on fracture level. We present one technique for preserving an adequate residual limb length in the face of significant proximal tibia comminution.

Transection of the thoracic aorta: assessment of a trauma system

A large, heavily populated area regionalized the care of critical trauma in 1980. To evaluate the system, we reviewed patient outcome for thoracic aortic transection due to blunt injury for the first 18 months of trauma system operation. Of the total of 86 patients, 43 were transferred to trauma centers, 8 to nontrauma centers, and 35 were either directly transported to the coroner or dead on arrival at the hospital. Of the eight patients transported to non-trauma centers, seven were in cardiopulmonary arrest during transport and the eighth was pronounced dead shortly after admission to the emergency department. Twenty-seven of the 43 patients transferred to trauma centers were dead within 24 minutes of admission. The cause of death was rupture of a transected aorta in 22 patients and other multiple injuries in the remaining 5. Sixteen were alive long enough in the emergency department for evaluation. Nine of these patients underwent correction of aortic transection as well as other injuries and all survived. Two of the nine survivors sustained partial or complete spinal cord damage. The remaining seven patients died, but in only one patient did the undiagnosed aortic injury contribute to the cause of death. This patient had a normal cineangiogram and the diagnosis was made at autopsy. He was considered potentially salvageable, so 9 of 10 potentially salvageable patients survived (90 percent). Of the total of 86 patients with aortic transection, 77 died (90 percent). This study shows that regionalization of trauma care offers an excellent chance for survival of patients with thoracic aortic transection.