Mark Pallis

Survival Comparison of Allograft and Autograft Anterior Cruciate Ligament Reconstruction at the United States Military Academy

Background: There is recent evidence that use of allograft tendons for anterior cruciate ligament (ACL) reconstruction in young patients may result in increased failure rates compared with autologous grafts. Hypothesis: Allograft ACL reconstruction will result in higher failure rates in young athletes compared with autograft reconstruction. Study Design: Cohort study; Level of evidence, 2. Methods: A prospective cohort study of cadets at the United States Military Academy (USMA) was performed to assess performance of ACL reconstructions performed before entrance to service. Members of the classes of 2007 through 2013 who had undergone prior ACL reconstruction were identified through the Department of Defense Medical Evaluation Review Board reporting and waiver process and evaluated on the first day of matriculation. These participants were followed during their tenure at the academy with revision ACL reconstruction as the primary outcome measure of interest. Kaplan-Meier survival analysis was performed for all graft types using STATA with significance set as P < .05. Results: A total of 120 cadets underwent 122 ACL reconstructions (2 bilateral) before matriculation and compose the prospective cohort. This cohort included 30 female and 90 male cadets. Of these 122 knees with prior ACL reconstructions, the grafts used were 61 bone–patellar tendon–bone (BTB), 45 hamstring, and 16 allograft. A total of 20 failures occurred among this cohort at an average of 545 days from matriculation. Of the failures requiring revision, 7 were BTB (11% of all BTB), 7 were allograft (44% of all allograft), and 6 were hamstring (13% of all hamstring). There was no significant difference in the graft failure between the BTB and hamstring autograft groups. In contrast, those who entered the USMA with an allograft were 7.7 times more likely to experience a subsequent graft failure during the follow-up period when compared with the BTB autograft group (hazard ratio = 7.74; 95% confidence interval [CI], 2.67-22.38; P < .001). When allografts were compared with all autografts combined, a similar increase failure was noted in the allograft group (hazard ratio = 6.71; 95% CI, 2.64-17.06; P < .001). Conclusion: In this young active cohort, individuals having undergone an allograft ACL reconstruction were significantly more likely to experience clinical failure requiring revision reconstruction compared with those who underwent autologous graft reconstruction. The authors recommend the use of autograft in ACL reconstruction in young athletes.

Epidemiology of Acromioclavicular Joint Injury in Young Athletes

Background: Acromioclavicular (AC) joint injuries, particularly sprains, are common in athletic populations and may result in significant time lost to injury. However, surprisingly, little is known of the epidemiology of this injury. Purpose: To define the incidence of AC joint injuries and to determine the risk factors for injury. Study Design: Descriptive epidemiological study. Methods: A longitudinal cohort study was performed to determine the incidence and characteristics of AC joint injury at the United States Military Academy between 2005 and 2009. All suspected AC joint injuries were reviewed by an independent orthopaedic surgeon using both chart reviews as well as assessments of radiological imaging studies. Injuries were graded according to the modified Rockwood classification system as well as dichotomized into low-grade (Rockwood types I and II) and high-grade (Rockwood types III, IV, V, and VI) injuries for analysis. Injury mechanisms, return-to-play timing, and athlete-exposures were documented and analyzed. χ2 and Poisson regression analyses were performed, with statistical significance set at P < .05. Results: During the study period, 162 new AC joint injuries and 17,606 person-years at risk were documented, for an overall incidence rate of 9.2 per 1000 person-years. The majority of the AC joint injuries were low-grade (145 sprains, 89%) injuries, with 17 high-grade injuries. Overall, male patients experienced a significantly higher incidence rate for AC joint injuries than female patients (incidence rate ratio [IRR], 2.18; 95% confidence interval [CI], 1.21-4.31). An AC joint injury occurred most commonly during athletics (91%). The incidence rate of AC joint injury was significantly higher in intercollegiate athletes than intramural athletics when using athlete-exposure as a measure of person-time at risk (IRR, 2.11; 95% CI, 1.31-3.56). Similarly, the incidence rate of AC injury was significantly higher among male intercollegiate athletes when compared to female athletes (IRR, 3.56; 95% CI, 1.74-8.49) when using athlete-exposure as the denominator. The intercollegiate sports of men’s rugby, wrestling, and hockey had the highest incidence rate of AC joint injury. Acromioclavicular injuries resulted in at least 1359 total days lost to injury and an average of 18.4 days lost per athlete. The average time lost to injury for low-grade sprains was 10.4 days compared with high-grade injuries at 63.7 days. Of the patients with high-grade injuries, 71% elected to undergo coracoclavicular/AC reconstructions. The rate of surgical intervention was 19 times higher for high-grade AC joint injuries than for low-grade injuries (IRR, 19.2; 95% CI, 7.64-48.23; P < .0001). Conclusion: Acromioclavicular separations are relatively common in young athletes. Most injuries occur during contact sports such as rugby, wrestling, and hockey. Male athletes are at greater risk than female athletes. Intercollegiate athletes are at greater risk than intramural athletes. The average time lost to sport due to AC joint injury was 18 days, with low-grade injuries averaging 10 days lost. High-grade injuries averaged 64 days lost to sport, and 71% elected to undergo surgical repair/reconstruction.

Characterization of spinal injuries sustained by American service members killed in Iraq and Afghanistan: A study of 2,089 instances of spine trauma

BACKGROUND This study sought to characterize spine injuries among soldiers killed in Iraq or Afghanistan whose autopsy results were stored by the Armed Forces Medical Examiner System. METHODS The Armed Forces Medical Examiner System data set was queried to identify American military personnel who sustained a spine injury in conjunction with wounds that resulted in death during deployment in Iraq or Afghanistan from 2003 to 2011. Demographic and injury-specific characteristics were abstracted for each individual identified. The raw incidence of spinal injuries was calculated and correlations were drawn between the presence of spinal trauma and military specialty, mechanism and manner of injury, and wounds in other body regions. Significant associations were also sought for specific injury patterns, including spinal cord injury, atlantooccipital injury, low lumbar vertebral fractures, and lumbosacral dissociation. Statistical calculations were performed using &khgr;2 statistic, z test, t test with Satterthwaite correction, and multivariate logistic regression. RESULTS Among 5,424 deceased service members, 2,089 (38.5%) were found to have sustained at least one spinal injury. Sixty-seven percent of all fatalities with spinal injury were caused by explosion, while 15% occurred by gunshot. Spinal fracture was the most common type of injury (n = 2,328), while spinal dislocations occurred in 378, and vertebral column transection occurred in 223. Fifty-two percent sustained at least one cervical spine injury, and spinal cord injury occurred in 40%. Spinal cord injuries were more likely to occur as a result of gunshot (p < 0.001), while atlantooccipital injuries (p < 0.001) and low lumbar fractures (p = 0.01) were significantly higher among combat specialty soldiers. No significant association was identified between spinal injury risk and the periods 2003 to 2007 and 2008 to 2011, although atlantooccipital injuries and spinal cord injury were significantly reduced beginning in 2008 (p < 0.001). CONCLUSION The results of this study indicate that the incidence of spinal trauma in modern warfare seems to be higher than previously reported. LEVEL OF EVIDENCE Epidemiologic study, level III.

The Epidemiology of Medial Collateral Ligament Sprains in Young Athletes

Background: A medial collateral ligament (MCL) knee sprain is a prevalent injury in athletic populations that may result in significant time lost to injury. Remarkably little is known of the epidemiology of this injury. Purpose: To define the incidence of MCL tears and to determine the demographic and athletic risk factors. Study Design: Descriptive epidemiological study. Methods: A longitudinal cohort study was performed to examine the epidemiology of isolated MCL sprains at the United States Military Academy (USMA) between 2005 and 2009. Charts and radiographic studies were reviewed by an independent orthopaedic surgeon to identify all new isolated MCL sprains resulting in time lost to sport and activity that occurred within the study period. Incidence rates (IRs) with 95% confidence intervals (CIs) were calculated per 1000 person-years at risk and by sex, sport, and level of competition. The IR per 1000 athlete-exposures (AEs) was also determined. Incidence rate ratios (IRRs) and respective 95% CIs were calculated between male and female students, intercollegiate and intramural athletes, and male and female intercollegiate athletes involved in selected sports. Chi-square and Poisson regression analyses were used to examine the relationship between the variables of interest and the incidence of MCL sprains, with statistical significance set at P < .05. Results: A total of 128 cadets sustained isolated MCL injuries during 17,606 student person-years from 2005 to 2009. This resulted in an IR of approximately 7.3 per 1000 person-years. Of the 128 injuries, 114 were in male athletes (89%) and 14 were in female athletes (11%). Male cadets had a 44% higher IR than did female cadets (7.60 vs 5.36, respectively), although this was not significant (P = .212). Of 5820 at-risk intercollegiate athletes, 59 (53 male, 6 female) sustained an isolated MCL sprain during 528,523 (407,475 male, 121,048 female) AEs for an overall IR of 10.14 per 1000 person-years and 0.11 per 1000 AEs. The IRR of MCL sprains of men compared with women involved in intercollegiate athletics was 2.87 (95% CI, 1.24-8.18) per 1000 person-years and 2.62 (95% CI, 1.13-7.47) per 1000 AEs. Of 21,805 at-risk intramural athletes, with quarterly participation, 16 (all male) sustained isolated MCL injuries during 225,683 AEs for an overall IR of 0.07 per 1000 AEs. The IRs of MCL injuries of intercollegiate and intramural athletes did not differ significantly. In intercollegiate sports, wrestling (0.57), judo (0.36), hockey (0.34), and rugby (men’s, 0.22; women’s, 0.23) had the highest IRs per 1000 AEs. When examining men’s intercollegiate athletics, the IRRs of wrestling (13.41; 95% CI, 1.80-595.27) and hockey (8.12; 95% CI, 0.91-384.16) were significantly higher compared with that of lacrosse. Among women’s intercollegiate sports as well as intramural sports, there were no significant differences in IRs. A median of 16 days was lost to injury, with 2407 total days lost for all injuries. Grade 1 MCL injuries lost a median of 13.5 days, while higher grade injuries lost a median of 29 days. Conclusion: Medial collateral ligament injuries are relatively common in athletic cohorts. The most injurious sports are contact sports such as wrestling, hockey, judo, and rugby. Male athletes are at a greater risk than female athletes. Intercollegiate athletes are at a greater risk than intramural athletes. The average amount of time lost per injury was 23.2 days, with greater time lost with higher grade sprains than grade 1 sprains.

Survivorship of Meniscal Allograft Transplantation in an Athletic Patient Population

Background: There are limited data evaluating the clinical outcomes of meniscal allograft transplantation (MAT) in physically active cohorts. Purpose: To determine the survivorship, complication rates, and functional outcomes of MAT in an active military population. Study Design: Case series; Level of evidence, 4. Methods: All military patients undergoing MAT between 2007 and 2013 were identified from the Military Health System. Previous/concomitant procedures, perioperative complications, reoperation rate, revision, and initiation of medical discharge for persistent knee disability were recorded. Univariate analysis was performed to identify associations between patient-based and surgical variables on selected endpoints. Results: A total of 230 MATs (227 patients; 228 knees) were identified; the mean patient age was 27.2 years (range, 18-46 years), and the cohort was predominately male (89%). Approximately half (51%) of the patients had undergone prior, nonmeniscal knee procedures. Medial MATs were performed in 160 (69%) cases, and isolated MATs were most common (60%). A total of 51 complications occurred in 46 (21.1%) patients, including a secondary tear or extrusion (9%). At a mean clinical follow-up of 2.14 years, 10 (4.4%) patients required secondary meniscal debridement, while 1 (0.4%) patient required revision MAT and 2 (0.9%) patients underwent total knee arthroplasty. After MAT, 50 (22%) patients underwent knee-related military discharge at a mean of 2.49 years postoperatively. Tobacco use (P = .028) was associated with significantly increased risk of failure, and operation by fellowship-trained surgeons trended toward significance as a protective factor (P = .078). Furthermore, high-volume surgeons (≥1 MAT/year; range, 9-35) had significantly reduced rates of failure (P = .046). Conclusion: While reporting low reoperation and revision rates, this investigation indicates that 22% of patients with MAT were unable to return to military duty due to persistent knee limitations at short-term follow-up. Increased surgical experience may decrease rates of failure after MAT. Careful patient selection and referral to subspecialty-trained, higher-volume surgeons should be considered to optimize clinical outcomes after MAT.

Success of High Tibial Osteotomy in the United States Military

Background: Historically, high tibial osteotomy (HTO) has been performed to treat isolated medial gonarthrosis with varus deformity. Purpose: To evaluate the occupational outcomes of HTO in a high-demand military cohort. Study Design: Case-control study; Level of evidence, 3. Methods: A retrospective analysis of active duty service members undergoing HTO for coronal plane malalignment and/or intra-articular pathology was performed using the Military Health System between 2003 and 2011. Demographic parameters and surgical variables, including rates of perioperative complications, secondary surgery, activity limitations, and medical discharge, were extracted from electronic medical records. For the current study, cumulative failure was defined as conversion to knee arthroplasty or postoperative medical discharge for persistent knee dysfunction. Univariate and multivariate analyses were performed to identify statistical associations with cumulative failure after HTO. Results: A total of 181 service members (202 HTOs) were identified at an average follow-up of 47.5 months (range, 24-96 months). Mean age was 35.7 years (range, 19-55 years), and the majority were men (93%) and of enlisted rank (78%). All index procedures utilized a valgus-producing, opening wedge technique. Concomitant or staged procedures were performed in 87 patients (48%), including 40 ligamentous, 48 meniscal, and 48 chondral procedures. Complications occurred in 19.3% of knees (n = 39), with unplanned reoperation in 26 knees (12.8%). Fifty-three patients (40.7%) had minor activity limitations during military duty postoperatively. Eleven knees (5.4%) underwent conversion to total knee arthroplasty. The cumulative failure rate was 28.2% (n = 51) at 2- to 8-year follow-up. Patient age younger than 30 years at the time of surgery was associated with an independently higher risk of failure, whereas sex, concomitant/staged procedures, and perioperative complications were not significantly associated with subsequent failure. Conclusion: At short- to midterm follow-up, nearly 72% of all service members undergoing HTO returned to military duty and were free from conversion knee arthroplasty.

SLAP Repairs With Combined Procedures Have Lower Failure Rate Than Isolated Repairs in a Military Population: Surgical Outcomes With Minimum 2-Year Follow-up.

Background: Injuries to the superior glenoid labrum represent a significant cause of shoulder pain among active patients. The physical requirements of military service may contribute to an increased risk of injury. Limited data are available regarding the success of superior labral anterior posterior (SLAP) repairs in an active military population. Purpose: To quantify the rate of clinical failure and surgical revision after isolated and combined SLAP repair. Study Design: Cohort study; Level of evidence, 3. Methods: All consecutive active-duty servicemembers undergoing arthroscopic repair of type II SLAP lesions at a single institution between 2006 and 2012 were identified. Patients with less than 2-year clinical follow-up and nonmilitary status were excluded. Demographic variables, surgical variables, and occupational outcomes were extracted from electronic medical records and confirmed with the US Army Physical Disability Agency database. Failure was defined as subsequent revision surgery or medical discharge with persistent shoulder complaints. Results: A total of 192 patients with SLAP repair were identified with a mean follow-up of 50.0 months (SD, 17.0 months). Isolated SLAP repair occurred in 31.3% (n = 60) versus 68.8% (n = 132) with concomitant procedures. At final follow-up, 37.0% (n = 71) of patients reported some subjective activity-related shoulder pain. Postoperative return to duty occurred in 79.6% (n = 153), and only 20.3% (n = 39) were discharged with continuing shoulder disability. The combined rotator cuff repair (96%; P = .023) and anteroinferior labral repair group (88%; P = .056) had a higher rate of functional return than isolated SLAP repair (70%). Thirty-one (16.1%) patients were classified as surgical failure and required revision. Of these, the majority of patients undergoing biceps tenodesis (76%) returned to active duty, as compared with revision SLAP repair (17%). Lower demand occupation and the presence of combined shoulder injuries (P = .011 and .016, respectively) were significantly associated with a lower risk of medical discharge and revision surgery, respectively. Conclusion: Favorable outcomes can be anticipated in the majority of military servicemembers after arthroscopic SLAP repair, particularly with combined shoulder injuries. Revision surgery occurred in 16% of patients after primary SLAP repair. Clinical Relevance: Isolated repair of unstable SLAP lesions and/or increased upper extremity demands are associated with higher failure rates in this population.

Enhanced casualty care from a Global Military Orthopaedic Teleconsultation Program

BACKGROUND Since its advent, telemedicine has facilitated access to subspecialty medical care for the treatment of patients in remote and austere settings. The United States military introduced a formal orthopaedic teleconsultation system in 2007, but few reports have explored its scope of practice and efficacy, particularly in a deployed environment during a time of conflict. METHODS All teleconsultations placed to the orthopaedic service between April 2009 and December 2012 were obtained and retrospectively reviewed. Case files were abstracted and anatomical location of injury, type of injury, origin of consult (country or Navy Afloat), branch of service, and treatment recommendations, were recorded for descriptive analysis. The final result of the consult was also determined, with service members transported from the combat theatre or deployment location defined as medically evacuated. Instances where teleconsultations averted a medical evacuation were also documented as a separate outcome. RESULTS Over a 32-month period, 597 orthopaedic teleconsultations were placed, with the majority derived from Army (46%) and Navy (32%) personnel deployed in Afghanistan, Iraq, or with Navy Afloat. Approximately 51% of consults involved the upper extremity, including 197 hand injuries, followed by lower extremity (37%) and spine (7.8%) complaints. Fractures comprised over half of all injuries, with the hand and foot most commonly affected. The average response time for teleconsultations was 7.54h. A total of 56 service members required immediate evacuation for further orthopaedic management, while at least 26 medical evacuations were prevented due to the teleconsultation system. CONCLUSIONS The teleconsultation system promotes early access to orthopaedic subspecialty care in a resource-limited, deployed military setting. The telemedicine network also appears to mitigate unnecessary aeromedical evacuations, reducing healthcare costs, lost duty time, and treatment delays. These findings have important meaning for the future of telemedicine in both the military and civilian setting. LEVEL OF EVIDENCE IV.

Medialized Clavicular Bone Tunnel Position Predicts Failure After Anatomic Coracoclavicular Ligament Reconstruction in Young, Active Male Patients.

Background: Recent radiographic data have suggested that medialized conoid tunnel placement greater than 25% of absolute clavicular length is correlated with early failure after anatomic coracoclavicular ligament reconstructions. A comparison with a larger active duty military cohort of clinical and radiographic outcomes can serve as a basis for standardizing surgical technique. Purpose: To establish the ideal radiographic tunnel position for anatomic coracoclavicular ligament reconstruction and to elucidate variables associated with early loss of reduction and ability to return to active-duty military service. Study Design: Case series; Level of evidence, 4. Methods: A retrospective review of the military’s electronic medical record between the years 2000 and 2013 was performed. All anatomic coracoclavicular reconstructions at a single institution were included for analysis, and nonanatomic or revision reconstructions were excluded. Radiographic failure was defined as 6 mm of superior clavicle displacement on immediate postoperative films. Results: A cohort of 38 patients underwent 39 anatomic coracoclavicular reconstructions. Average follow-up time was 26 months (range, 1.2-92 months). A total of 20 radiographic failures were identified, with an average conoid tunnel ratio of 0.27. When conoid tunnel ratios were compared with a reference ratio of 0.20 to 0.25, increased risk of failure was statistically significant with lateralization greater than 0.20 (P = .018; odds ratio [OR] = 40 [95% CI, 1.05-999.06]) or with medialization of 0.251 to 0.30 (P = .002; OR = 39 [95% CI, 1.58-944.36]) or greater than 0.30 (P = .029; OR = 21 [95% CI, 0.77-562.15]). Medialization of the trapezoid position greater than 0.16 (vs a range of 0.13-0.16) was also found to be significant for failure (P < .023; OR = 8 [95% CI, 1.33-48.18]). However, these significant findings did not correlate with symptoms or ability to return to duty (P > .05). Conclusion: The optimal technique for treating acromioclavicular separations has yet to be determined. Recently, anatomic coracoclavicular reconstruction has demonstrated biomechanical superiority to previously described methods. The findings of optimal tunnel positioning in anatomic reconstructions from this large active-duty military cohort can assist preoperative planning to reduce failure rates when treating these difficult injuries.

The Boxer's Fracture: Splint Immobilization Is Not Necessary

Fractures of the fifth metacarpal neck, or boxers fractures, are common, particularly among young men. Because of the high frequency of this injury, there is a considerable range of treatment options. The purpose of this systematic review was to determine whether reduction and splint or cast immobilization is necessary for fractures of the fifth metacarpal neck. The authors conducted a systematic review of all published studies that randomized these fractures to cast immobilization vs treatment with soft wrap without reduction. Cast immobilization is not superior to soft wrap without reduction in most cases. The study found that reduction and cast immobilization is not necessary for boxers fractures. [Orthopedics. 2016; 39(3):188-192.].