Travis C. Burns

Heterotopic ossification following traumatic and combat-related amputations. Prevalence, risk factors, and preliminary results of excision.

BACKGROUND Although infrequently reported in amputees previously, heterotopic ossification has proven to be a common and problematic clinical entity in our recent experience in the treatment of traumatic and combat-related amputations related to Operation Enduring Freedom and Operation Iraqi Freedom. The purpose of the present study was to report the prevalence of and risk factors for heterotopic ossification following trauma-related amputation as well as the preliminary results of operative excision. METHODS We identified 330 patients with a total of 373 traumatic and combat-related amputations who had been managed at our centers between September 11, 2001 and November 30, 2005. We reviewed the medical records and radiographs of 187 patients with 213 amputations who had adequate radiographic follow-up. Additional analysis was performed for twenty-four patients with twenty-five limbs that required excision of symptomatic lesions. The mechanism and zone of injury, amputation level, timing of excision, use of prophylaxis against recurrence, and other confounding variables were examined. Outcomes were assessed by determining clinical and radiographic recurrence rates, perioperative complications, preoperative and follow-up pain medication requirements, and the ability to be fit with a functional prosthesis. RESULTS Heterotopic ossification was present in 134 (63%) of 213 residual limbs, with twenty-five lesions requiring excision. A final amputation level within the zone of injury was a risk factor for both the development and the grade of heterotopic ossification (p < 0.05). A blast mechanism was predictive of occurrence (p < 0.05) but did not correlate with grade. All patients who had been managed with excision were tolerating the prosthetic limb at an average of twelve months of follow-up. Twenty-three limbs demonstrated no evidence of recurrence, and two limbs had development of clinically asymptomatic, radiographically minimal recurrences. Six patients experienced wound-related complications that required reoperation, and two patients required subsequent minor revision surgery. There was a significant decrease in the use of pain medication following surgery (p < 0.05). CONCLUSIONS Heterotopic ossification following trauma-related amputation is more common than the literature would suggest, particularly following amputations that are performed within the initial zone of injury and those that are due to blast injuries. Many patients are asymptomatic or can be successfully managed with modification of the prosthesis. For patients with refractory symptoms, surgical excision is associated with low recurrence rates and decreased medication requirements, with acceptable complication rates.

Infectious Complications of Open Type III Tibial Fractures among Combat Casualties

BACKGROUND Combat is associated with high-energy explosive injuries, often resulting in open tibial fractures complicated by nonunion and infection. We characterize the infections seen in conjunction with combat-associated type III tibial fractures. METHODS We performed a retrospective medical records review to identify US military service members wounded in Iraq or Afghanistan with open diaphyseal tibial fractures who were admitted to our facility (Brooke Army Medical Center, Fort Sam Houston, Texas) between March 2003 and September 2006. RESULTS Of the 62 patients with open tibial fractures who were identified in our initial search, 40 had fractures that met our inclusion criteria as type III diaphyseal tibial fractures. Three patients were excluded because their fractures were managed with early limb amputation, and 2 were excluded because of incomplete follow-up records. Twenty-seven of these 35 patients had at least 1 organism present in initial deep-wound cultures that were performed at admission to the hospital. The pathogens that were identified most frequently were Acinetobacter, Enterobacter species, and Pseudomonas aeruginosa. Thirteen of the 35 patients had union times of >9 months that appeared to be associated with infection. None of the gram-negative bacteria identified in the initial wound cultures were recovered again at the time of a second operation; however, all patients had at least 1 staphylococcal organism. One patient had an organism present during initial culture and in the nonunion wound; this organism was a methicillin-resistant Staphylococcus aureus strain that was inadvertently not treated. Five of 35 patients ultimately required limb amputation, with infectious complications cited as the reason for amputation in 4 of these cases. CONCLUSIONS Combat-associated type III tibial fractures are predominantly associated with infections due to gram-negative organisms, and these infections are generally successfully treated. Recurrent infections are predominantly due to staphylococci.

Return to Duty Rate of Amputee Soldiers in the Current Conflicts in Afghanistan and Iraq

BACKGROUND The purpose of this study was to determine the percentage of amputee soldiers who sustained their injury during the current conflicts in Afghanistan and Iraq and have returned to duty. In addition, the authors plan to identify the factors that influence the amputees likelihood to return to duty. METHODS The computerized records of amputee soldiers who presented to the Physical Evaluation Board between October 1, 2001 and June 1, 2006 were reviewed. This data were crossreferenced with the Military Amputee Database. The following variables were extracted: age, gender, pay grade, amputation level, and final disposition. RESULTS During the period reviewed, there were 395 major limb amputees that met inclusion criteria. Of those, 65 returned to active duty (16.5%). The average age of amputees returning to duty was more than 4 years older than those who separated from the service (31.4 vs. 27.2), p < 0.0001. Officers and senior enlisted personnel returned to duty at a higher rate (35.3% and 25.5%, respectively) when compared with junior enlisted personnel (7.0%), p < 0.0001. Those with multiple extremity amputations have the lowest return to duty rate at 3%, when compared with the overall return to duty rate for single extremity amputees (20%), p < 0.0001. CONCLUSION During the 1980s, 11 of 469 amputees returned to active duty (2.3%). The number of amputees returning to duty has increased significantly, from 2.3% to 16.5%, due to advancements in combat casualty care and the establishment of centralized amputee centers.

Infectious complications and soft tissue injury contribute to late amputation after severe lower extremity trauma.

BACKGROUND Although most combat-related amputations occur early for unsalvageable injuries, >15% occur late after reconstructive attempts. Predicting which patients will abandon limb salvage in favor of definitive amputation has not been explored. The purpose of this study was to identify factors contributing to late amputation for type III open tibia fractures sustained in combat. METHODS Operative databases were reviewed to identify all combat-related type III open diaphyseal tibia fractures from March 2003 to September 2007. Patients were categorized based on their definitive treatment: group I, limb salvage; group II, early amputation (<12 weeks postinjury); group III, late amputation (≥ 12 weeks postinjury). Injury, treatment, and complication data were extracted from medical records and compared across groups. RESULTS We identified 213 consecutive fractures, including 166 (77.9%) treated definitively with limb salvage, 36 (16.9%) with early amputation, and 11 (5.2%) with late amputation. There was no difference in fracture severity among the three groups. Before amputation, group III was more likely to use autograft and bone morphogenic protein (27.3%), compared with group I (4.8%) and group II (0%), and was more likely to undergo rotational flap coverage (45.5%), compared with group II (0%). Group III patients had the highest average number of revision surgeries and rate of deep soft tissue infection and were more likely to have osteomyelitis (54.5%) before amputation compared with group I (13.9%) and group II (16.7%). CONCLUSION Patients definitively managed with late amputation were more likely to have soft tissue injury requiring flap coverage and have their limb salvage course complicated by infection.

Heterotopic Ossification in the Residual Limbs of Traumatic and Combat-Related Amputees

&NA; Reports on the occurrence and treatment of heterotopic ossification in amputees are rare. Heterotopic ossification in the residual limbs of amputees may cause pain and skin breakdown and complicate or prevent optimal prosthetic fitting and utilization. Basic science research has shed light on the cellular and molecular basis for this disease process, but many questions remain unanswered. The recent experience of the military amputee centers with traumatic and combat‐related amputations has demonstrated a surprisingly high prevalence of heterotopic ossification in residual limbs. Primary prophylactic regimens, such as nonsteroidal antiinflammatory drugs and local irradiation, which have proved to be effective in preventing and limiting heterotopic ossification in other patient populations, have not been studied in amputees and generally are not feasible in the setting of acute traumatic amputation. When nonsurgical measures such as activity and repeated prosthetic modifications fail to provide relief, surgical excision has provided good early clinical results, with low rates of recurrence and acceptable complication rates in military amputees.

Microbiology and injury characteristics in severe open tibia fractures from combat.

BACKGROUND: Type III open tibia fractures are common combat injuries. The purpose of the study was to evaluate the effect of injury characteristics and surveillance cultures on outcomes in combat-related severe open tibia fractures. METHODS: We conducted a retrospective study of all combat-related open Gustilo and Anderson (G/A) type III diaphyseal tibia fractures treated at our centers between March 2003 and September 2007. RESULTS: One hundred ninety-two Operation Iraqi Freedom/Operation Enduring Freedom military personnel with 213 type III open tibial shaft fractures were identified. Fifty-seven extremities (27%) developed a deep infection and 47 extremities (22%) ultimately underwent amputation at an average follow-up of 24 months. Orthopedic Trauma Association type C fractures took significantly longer to achieve osseous union (p = 0.02). G/A type III B and III C fractures were more likely to undergo an amputation and took longer to achieve fracture union. Deep infection and osteomyelitis were significantly associated with amputation, revision operation, and prolonged time to union. Surveillance cultures were positive in 64% of extremities and 93% of these cultures isolated gram-negative species. In contrast, infecting organisms were predominantly gram-positive. CONCLUSIONS: Type III open tibia fractures from combat unite in 80.3% of cases at an average of 9.2 months. We recorded a 27% deep infection rate and a 22% amputation rate. The G/A type is associated with development of deep infection, need for amputation, and time to union. Positive surveillance cultures are associated with development of deep infection, osteomyelitis, and ultimate need for amputation. Surveillance cultures were not predictive of the infecting organism if a deep infection subsequently develops. LEVEL OF EVIDENCE: III.

Femoral suspension devices for anterior cruciate ligament reconstruction: Do adjustable loops lengthen?

Background: Cortical suspension devices are commonly used for femoral graft fixation during anterior cruciate ligament (ACL) reconstructive surgery. Adjustable-length fixation devices provide technical advantages over fixed-length loops but may be more susceptible to lengthening during cyclic loading. Hypothesis: Both fixed-length and adjustable-length femoral cortical suspension devices would withstand ultimate loads greater than those normally experienced by the native ACL and would prevent clinically significant lengthening during prolonged cyclic loading. Study Design: Controlled laboratory study. Methods: Mechanical testing was performed on 3 ACL graft cortical suspensory devices by use of an extended cyclic loading (4500 cycles at 10-250 N) and pull-to-failure protocol. Two adjustable-length devices were additionally tested with the free suture ends tied. Results: Total displacement after 4500 cycles of tensioning at variable loads (expressed as mean ± SD) was 42.45 mm (±7.01 mm) for the Arthrex TightRope RT, 5.76 mm (±0.35 mm) for the Biomet ToggleLoc, and 1.34 mm (±0.03 mm) for the Smith & Nephew EndoButton CL Ultra (P < .001). The Arthrex TightRope reached clinical failure of 3 mm lengthening after fewer cycles (1349 ± 316) than the Biomet ToggleLoc (2576 ± 73) (P < .001). The Smith & Nephew EndoButton did not reach clinical failure during cyclic testing. With the free suture ends tied, after 4500 cycles, the Arthrex TightRope had a significant decrease in lengthening to 13.36 ± 1.86 mm (P < .037) There was also a significant difference in ultimate load between the TightRope (809.11 ± 52.94 N) and the other 2 constructs (P < .001). Conclusion: The ultimate load of all graft-fixation devices exceeded the forces likely to be experienced in a patient’s knee during the early postoperative rehabilitation period. However, the adjustable-length fixation devices experienced a clinically significant increase in loop lengthening during cyclic testing. This lengthening is partially caused by suture slippage into the adjustable-length loop. Clinical Relevance: Adjustable-length ACL graft cortical suspension devices lengthen under cyclic loads because free suture ends are pulled into the adjustable loop. This may allow for graft-fixation device lengthening during the acute postoperative period.

Prevalence of Late Amputations During the Current Conflicts in Afghanistan and Iraq

During the current conflicts, over 950 soldiers have sustained a combat-related amputation. The majority of these are acute, but an unknown number are performed months to years after the initial injury. The goal of this study is to determine the prevalence of late amputations in our combat wounded. Electronic medical records and radiographs of all soldiers who had a combat-related, lower extremity injury that resulted in amputation were reviewed to confirm demographic, injury, and amputation information. Time to amputation was defined as a late amputation when it occurred more than 12 weeks following the date of injury. There were 348 major limb amputees that met inclusion criteria. Fifty-three (15.2%) amputees had a late amputation (range = 12 wk-5.5 yr). While the majority of combat-related amputations occur acutely, more than 15% occur late. This study demonstrates that further research is needed to identify predictive factors and outcomes of the late amputation.

Return to Duty After Type III Open Tibia Fracture

Introduction: Despite the high incidence of battlefield orthopaedic injuries, long-term outcomes and return to duty (RTD) status have rarely been studied. Our purpose was to determine the RTD rate for soldiers who sustained Type III open tibia fractures in active combat. Methods: One hundred fifteen soldiers who sustained battle-related Type III open tibia fractures were retrospectively reviewed. The Army Physical Evaluation Board database was reviewed to determine which soldiers were able to RTD and the disability ratings of those not able to RTD. Results: The overall RTD rate was 18%, isolated open fractures had a RTD rate of 22%, salvaged extremities had a RTD rate of 20.5%, and amputees had a RTD rate of 12.5%. Older age and higher rank were both significant factors in increasing the likelihood of RTD and amputees had significantly higher disability ratings than those with salvaged extremities. Conclusion: Despite the severe nature of combat extremity wounds, 20% of patients with salvaged Type III open tibia fractures and 22% with isolated injuries were able to return to active duty. These rates are similar to those reported for civilian amputees. Amputees in our cohort were less likely to RTD.

Outcomes After Bankart Repair in a Military Population: Predictors for Surgical Revision and Long-Term Disability

PURPOSE To quantify the rate of surgical failure after anterior shoulder stabilization procedures, as well as to identify demographic and surgical risk factors associated with poor outcomes. METHODS All Army patients undergoing arthroscopic or open Bankart repair for shoulder instability were isolated from the Military Health System Management Analysis and Reporting Tool between 2003 and 2010. Demographic variables (age, gender) and surgical variables (treatment facility volume, admission status, surgical technique) were extracted. Rates of surgical failure, defined as subsequent revision surgery or medical discharge with persistent shoulder complaints, were recorded from the electronic medical record and US Army Physical Disability Agency database. Risk factor analysis was performed with univariate t tests, χ(2) tests, and a multivariable logistic regression model with failure as the outcome. RESULTS A total of 3,854 patients underwent Bankart repair during the study period, with most procedures having been performed arthroscopically (n = 3,230, 84%) and on an outpatient basis (n = 3,255, 84%). Patients were predominately men (n = 3,531, 92%), and the mean age was 28.0 years (SD, 7.5 years). A total of 193 patients (5.0%) underwent revision stabilization whereas 339 patients (8.8%) were medically discharged with complaints of shoulder instability, for a total combined failure rate of 13.8% (n = 532). Univariate analyses showed no significant effect for gender; however, younger age, higher facility volume, open repair, and inpatient status were significant factors associated with subsequent surgical failure. Multivariable analyses confirmed that young age (odds ratio [OR], 0.93; 95% confidence interval [CI], 0.91 to 0.96; P < .001), open repair (OR, 0.52; 95% CI, 0.36 to 0.75; P = .001), and inpatient status (OR, 0.58; 95% CI, 0.40 to 0.84; P = .004) were independently associated with failure by revision surgery. CONCLUSIONS Young age remains a significant risk factor for surgical failure after Bankart repair. Patients who underwent arthroscopic Bankart repair had a significantly lower surgical failure rate (4.5%) than patients who underwent open anterior stabilization (7.7%). Despite advances in surgical technique, 1 in 20 military service members required revision surgery after failed primary stabilization in this study. LEVEL OF EVIDENCE Level IV, therapeutic case series.