Most Military Arthroplasty Surgeons Have a Low Volume Practice in the Military Health System.

Background: The purpose of this study is to investigate hospital and surgeon joint arthroplasty volume in the Military Health System (MHS). A secondary aim is to look at interruption in physician practice during the study period. Methods: Review of all patients undergoing hip or knee arthroplasty in the MHS over >5-year period to examine hospital and surgeon volume for total joint arthroplasty (TJA). We stratified hospital and surgeon volume into low, medium, and high volumes. Results: Fifty surgeons performed at least 50 hip and/or knee arthroplasties during this period. These surgeons accounted for 75% of TJA in the MHS. When stratified by cases per year, the median primary total hip arthroplasty (THA) per year was 31.4 and primary total knee arthroplasty (TKA) was 47.3 per year. Regarding the volume threshold for primary and revision TJA, all hospitals were classified as having low volumes for both THA and unicompartmental knee arthroplasty/TKA. There were 0 high volume, 7 (21.9%) medium volume, and 25 (78.1%) low volume THA surgeons; there was 1 high volume TKA surgeon, 17 (34.7%) medium volume, and 31 (63.3%) low volume TKA surgeons. The average duration of clinical activity for fellowship-trained surgeons over the study period was 4.0 years, and the average duration of clinical inactivity was 263.7 days (17.9% of practice period). Conclusions: The highest-volume military arthroplasty surgeons have low volume when compared to their civilian colleagues. There are also long periods of clinical practice interruption. These findings stress the need to establish civilian-DOD or DOD-VA working relationships so that MHS patients experience the best possible care by high-volume surgeons in high-volume surgical centers.

Intrawound Antibiotic Powder Decreases Frequency of Deep Infection and Severity of Heterotopic Ossification in Combat Lower Extremity Amputations.

BACKGROUND: Amputations sustained owing to combat-related blast injuries are at high risk for deep infection and development of heterotopic ossification, which can necessitate reoperation and place immense strain on the patient. Surgeons at our institution began use of intrawound antibiotic powder at the time of closure in an effort to decrease the rate of these surgical complications after initial and revision amputations, supported by compelling clinical evidence and animal models of blast injuries. Antibiotic powder may be useful in reducing the risk of these infections, but human studies on this topic thus far have been inconclusive. PURPOSE: We sought to determine whether administration of intrawound antibiotic powder at the time of closure would (1) decrease the risk of subsequent deep infections of major lower-extremity combat-related amputations, and (2) limit formation and decrease severity of heterotopic ossification common in the combat-related traumatic residual limb. METHODS: Between 2009 and 2015, 252 major lower extremity initial and revision amputations were performed by a single surgeon. Revision cases were excluded if performed specifically to address deep infection, leaving 223 amputations (88.5%) for this retrospective analysis. We reviewed medical records to collect patient information, returns to the operating room for subsequent infection, and microbiologic culture results. We also reviewed radiographs taken at least 3 months after surgery to determine the presence and severity of heterotopic ossification using the Walter Reed classification system. We grouped cases according to whether limbs underwent initial or revision amputations, and whether the limbs had a history of a prior infection. Apart from the use of antibiotic powder and duration of followup, the groups did not differ in terms of age, mechanism of injury, or sex. We then calculated the absolute risk reduction for infection and heterotopic ossification and the number needed to treat to prevent an infection. RESULTS: Overall, administration of antibiotic powder resulted in a 13% absolute risk reduction of deep infection (14 of 82 [17%] versus 42 of 141 [30%]; p = 0.03; 95% CI, 0.20%-24.72%). In revision amputation surgery, the absolute risk reduction of infection with antibiotic powder use was 16% overall (eight of 58 versus 17 of 57; 95% CI, 1.21%-30.86%), and 25% for previously infected limbs (eight of 46 versus 14 of 33; 95% CI, 4.93%-45.14%). The number needed to treat to prevent one additional deep infection in amputation surgery is eight in initial amputations, seven in revision amputations, and four for revision amputation surgery on previously infected limbs. With the numbers available, we observed no reduction in the risk of heterotopic ossification with antibiotic powder use, but severity was decreased in the treatment group in terms of the number of residual limbs with moderate or severe heterotopic ossification (three of 12 versus 19 of 34; p = 0.03). CONCLUSIONS: Our findings show that administration of intrawound antibiotic powder reduces deep infection in residual limbs of combat amputees, particularly in the setting of revision amputation surgery in apparently aseptic residual limbs at the time of the surgery. Furthermore, administration of antibiotic powder for amputations at time of initial closure decreases the severity of heterotopic ossification formation, providing a low-cost adjunct to decrease the risk of two complications common to amputation surgery.Level of Evidence Level III, therapeutic study.

Treatment of Prosthetic Joint Infection: Established Patient Relationships May Impact Medical Decision-Making.

BACKGROUND: Choosing the intervention for prosthetic joint infections, whether debridement, antibiotics, and implant retention (DAIR), or explant and antibiotic spacer placement, is multifactorial. One characteristic that may influence this decision is a previously established relationship with the patient. We hypothesized that patients receiving their arthroplasty at an outside institution and presenting with infection would be more likely to undergo removal of their implant without an attempt at DAIR compared to patients who underwent primary arthroplasty at the investigating institution. METHODS: The institutional database was queried for primary total hip and knee arthroplasty infections. Manual review of medical records was performed, excluding patients who did not meet the Musculoskeletal Infection Society definition of infection. Patient demographics, medical comorbidities, presenting infection characteristics, and surgical intervention were collected. Multivariable analysis was performed to determine the independent predictors of treatment. RESULTS: A total of 270 patients were included for analysis. McPherson score (P < .001) and duration of symptoms (P < .001) were associated with subsequent treatment. Additionally, when controlling for age, gender, symptom duration category, procedure, McPherson score, and American Society of Anesthesiologists category, patients with index procedures at outside hospitals were more likely to undergo implant removal (odds ratio, 36.30; 95% confidence interval, 8.16-161.51; P < .001). CONCLUSION: Patients receiving their primary arthroplasty at an outside hospital and presenting with infection are more likely to undergo removal of hardware as their initial treatment. To avoid treatment bias, institutional protocols should be implemented to guide the shared decision-making process.

Clinical Outcomes After Extracorporeal Shock Wave Therapy for Chronic Plantar Fasciitis in a Predominantly Active Duty Population.

Chronic plantar fasciitis is a common cause of foot pain, with conservative treatment providing relief for most patients. However, because of the common occurrence of this pathology, this leaves many patients dissatisfied. The purpose of the present study was to determine the effectiveness of extracorporeal shock wave therapy (ESWT) to treat chronic plantar fasciitis (PF) in a largely active duty population. A review of 82 patients (115 heels) who had undergone ESWT for chronic PF was performed. Outcome data were obtained by patient telephone interviews. All ESWT was conducted at 24 kV for 2000 shocks. Of the 82 patients (115 heels), 76 (93%; 111 heels) agreed to participate. Their mean age was 42 ± 10 years, with 41 males (54%) and 35 females (46%). The mean follow-up period was 42 ± 22 months. Of the patients, 73.6% were active duty military personnel. The mean preoperative pain score of 7.8 ± 2 had improved to 2.5 ± 2 at the last follow-up visit (p <.0001). Active duty patients reported a mean improvement in pain of 4.8 ± 3 compared with 6.8 ± 3 in non-active duty patients (p = .005). Of the 76 patients, 75 (98%) underwent 1 ESWT session, and 1 (2%) requiring 2 sessions. Overall, 74% of patients rated the outcome of their procedure as either good or excellent, with 87% stating that ESWT was successful. Ten patients (18%) left the military because of continued foot pain, with 76% able to return to running. For patients with chronic PF, these results support the use of ESWT to relieve pain in >85% of patients, with a preponderance for better pain relief in patients who are not active duty military personnel.

No clinically meaningful weight changes in a young cohort following total joint arthroplasty at 3-year follow-up.

BACKGROUND: Total joint arthroplasty (TJA) is one of the most successful operations. There is little in the literature regarding weight change following TJA, particularly in a young cohort. METHODS: Retrospective analysis of 181 primary total hip arthroplasty (THA) and 185 primary total knee arthroplasty (TKA) patients was conducted. We reviewed preoperative and post-operative weights and post-operative body mass index at 3 and 6 months, 1 year, 2 and 3 years. We evaluated expected versus actual weight gain, and performed subgroup analyses of obese versus non-obese patients and active duty versus civilian patients. We used a minimal clinically meaningful weight change from baseline of ≥5%. RESULTS: One hundred and fifty-one (41.3%) patients were active duty military service members with the mean age of 53 ± 11.1 years. In TKA patients, statistically significant differences were found in mean weights at 3 months (-1.8%, P ≤ 0.0001) and 2 years (+1.9%, P = 0.0006). In THA patients, statistically significant weight gains were found at 6 months (+1.1%, P = 0.006). For obese TKA patients, significant weight changes were observed at 3 months (-2.5%, P ≤ 0.0001), and none in the obese THA group. There were no statistical or clinically meaningful weight changes in the non-obese TKA or THA groups. There was a clinically meaningful weight gain in active duty TKA patients at 3 years (5.18%, P = 0.17). CONCLUSION: Despite a theoretical ability to lose weight following TJA, patients maintain their preoperative weight following TJA. We found a clinically meaningful weight gain at 3 years post-operatively only in active duty TKA patients. Overall, however, we found no clinically significant weight changes following TJA at 3-year follow-up.

Outcomes of Hip Arthroscopy in the Older Adult: A Systematic Review of the Literature.

BACKGROUND: The indications for hip preservation surgery have expanded to include treatment of hip pathology in older adults. While several studies have examined the efficacy of hip arthroscopy in the setting of osteoarthritis, there has been no review of outcomes in older adults. PURPOSE: To review the outcomes of hip arthroscopy in older adults and identify factors associated with treatment failures. STUDY DESIGN: Systematic review. METHODS: PubMed, EMBASE, and the Cochrane Library were searched through March 2016 for studies reporting outcomes of primary hip arthroscopy in patients older than 40 years. Inclusion in the review was based on age, patient-reported outcome (PRO) measures, and duration of follow-up. Two authors screened the results and extracted data for use in this review. Standardized mean difference was calculated to estimate effect size for PRO scores within studies. RESULTS: Eight studies with 401 total patients undergoing hip arthroscopy for femoroacetabular impingement (FAI) or labral tears were included in this review. Seven of the 8 studies reported favorable PRO scores and significant postoperative improvement with moderate to large effect size. The included studies demonstrated a trend toward higher effect sizes with an increasing percentage of labral repair compared to isolated labral debridement. The complication rate was comparable to that of previous reports involving younger patients; however, the overall reoperation rate was 20.8%. Conversion to hip arthroplasty ranged from 0% to 30%, with an overall conversion rate of 18.5% at a mean time of 17.5 months following arthroscopy. The most common risk factors for conversion to arthroplasty were low preoperative PRO scores and advanced arthritis. CONCLUSION: Hip arthroscopy appears to be a safe and efficacious treatment for labral tears and FAI in older patients who do not have significant underlying degenerative changes. However, in this population, there is a significant proportion of patients who eventually require hip arthroplasty. Outcomes may be affected by type of treatment (ie, labral debridement vs repair). Additional high-quality studies are needed to understand how these factors affect outcomes.

Diagnosing the Undiagnosed: Osteoporosis in Patients Undergoing Lumbar Fusion.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: The aim of the study was to report the incidence of undiagnosed osteoporosis in patients undergoing lumbar spine fusion using computed tomography (CT) Hounsfield units (HU). SUMMARY OF BACKGROUND DATA: We used a recent technique utilizing HU to estimate bone mineral density (BMD) of the lumbar spine and hypothesized that this technique would reveal a high percentage of undiagnosed osteoporotic patients undergoing transforaminal lumbar interbody fusion (TLIF). METHODS: We reviewed patients older than 50 years undergoing TLIF from a single-center and multiple surgeons. We determined the mean HU of L4 on axial CT. Average HU values for patients with diagnosed lumbar osteoporosis (DEXA BMD <0.75 g/cm) were compared to patients with osteopenia and normal BMD (between 0.75 and 0.9 g/cm and >0.9 g/cm, respectively). The percentage of patients with HU values consistent with osteoporosis, but without any formal evaluation, was also calculated. RESULTS: Over 10 years, 143 patients older than 50 years underwent TLIF, and 128 had available perioperative lumbar CT scans. Men and Women comprised 60.2% and 39.8% of the population, respectively. Average age was 61.5 years (range: 50.0-83.5 years). Twenty-nine patients had both dual-energy X-ray absorptiometry and CT data available for analysis. There was a significant association with decreased HU in patients with lumbar BMD less than 0.75 g/cm (105.6 HU, 95% confidence interval [CI] 6.76) in comparison to patients with osteopenia (146.0 HU, 95% CI 4.09) and with normal BMD (165.9, 95% CI 21.35). Ten men (7.8%) and 15 women (11.7%) had HU values consistent with osteoporosis. Sixty-four percent of patients with osteoporotic HU values had never been formally evaluated for the disease. CONCLUSION: HU may be an alternative to screening preoperative dual-energy X-ray absorptiometry scan and can minimize costs and resource utilization. We found a large proportion of patients older than 50 years undergoing TLIF had HU levels consistent with undiagnosed osteoporosis of the lumbar spine. LEVEL OF EVIDENCE: 4.

Fifty Most-Cited Articles in the Orthopaedic Treatment of the Hip.

This study sought to identify the 50 most-cited articles in the literature pertaining to the surgical treatment of the hip, which has not yet been done to the authors' knowledge. In December 2014, an all-years search of the Thompson Institute for Scientific Information Web of Science was conducted for the term ``hip.'' Articles were sorted from most to least cited. Citations per article ranged from 3176 to 372. The majority of the articles were clinical in nature (64%) and hip arthroplasty was the predominant focus (70%). Eight different journals were included. The majority of the articles were published since the 1990s. Sixty-two percent of the articles originated from U.S. institutions. Only 12% of the articles were level I or II evidence with the majority being level IV evidence (44%). This study highlights the paucity of high-quality evidence, and further well-designed studies are needed to guide the future direction of hip surgery.

Clinical and Radiographic Outcomes of Transforaminal Lumbar Interbody Fusion in Patients with Osteoporosis.

Study Design Retrospective review. Objective To compare clinical outcomes after transforaminal lumbar interbody fusion (TLIF) in patients with and patients without osteoporosis. Methods We reviewed all patients with 6-month postoperative radiographs and computed tomography (CT) scans for evaluation of the interbody cage. CT Hounsfield unit (HU) measurements of the instrumented vertebral body were used to determine whether patients had osteoporosis. Radiographs and CT scans were evaluated for evidence of implant subsidence, migration, interbody fusion, iatrogenic fracture, or loosening of posterior pedicle screw fixation. Medical records were reviewed for persistence of symptoms or recurrence of symptoms. Results The final data analysis included 18 (20.5%) patients with osteoporosis and 70 (79.5%) patients without osteoporosis. Males comprised 50% of patients with osteoporosis, and 64.3% of patients without osteoporosis. The mean age was significantly higher in the osteoporotic group (65.2 years) versus the nonosteoporotic group (56.9 years; p < 0.0001). We found significantly higher rates of subsidence (72.2 versus 45.7%, p = 0.05) and iatrogenic fractures (16.7% versus 1.4%, p = 0.03) in the osteoporotic group. In addition, the osteoporotic group had significantly higher radiographic complication rates compared with the nonosteoporotic group (77.8 versus 48.6%, p = 0.03). There was no difference between groups for revision surgery (16.6 versus 14.3%, p = 0.78) or postoperative symptoms (44.4% versus 50.0%, p = 0.69). Conclusions Our data demonstrated significantly increased rates of cage subsidence, iatrogenic fracture, and overall radiographic complications in patients with osteoporosis. However, these radiographic complications did not predispose patients with osteoporosis to an increased risk of surgical revision or worse clinical outcomes.

Operative management of complex lumbosacral dissociations in combat injuries.

BACKGROUND CONTEXT: As war injury patterns have changed throughout Operations Iraqi and Enduring Freedom (OIF and OEF), a relative increase in the incidence of complex lumbosacral dissociation (LSD) injuries has been noted. Lumbosacral dissociation injuries are an anatomical separation of the spinal column from the pelvis, and represent a manifestation of severe, high-energy trauma. PURPOSE: This study aimed to assess the clinical outcomes of combat-related LSD injuries at a mean of 7 years following operative treatment. STUDY DESIGN: This is a retrospective review. PATIENT SAMPLE: We identified 20 patients with operatively managed LSDs. OUTCOME MEASURES: Time from injury to arrival in the United States, operative details, fixation methods, postoperative complications, time to retirement from military service, disability, and ambulatory status at latest follow-up. METHODS: We performed a retrospective review of outcomes of all patients with operatively managed combat-related LSD from January 1, 2003 to December 31, 2011. RESULTS: Twenty patients met inclusion criteria and were treated as follows: posterior spinal fusion (12, 60%), sacroiliac screw fixation (7, 35%), and combined anterior-posterior fusion for associated L3 burst fracture (1, 5%). The mean age was 28.2±6.4 years old. The most common mechanism of injury was mounted improvised explosive device (IED, 55%). On average, 2.2 spinal regions were injured per patient. Neurologic dysfunction was present in 15 patients. Three patients underwent operative stabilization of their injuries before evacuation to the United States. Four patients had a postoperative wound infection and two patients underwent reoperation. Mean follow-up was 85.9 months (range: 39.7-140.8 months). At most recent follow-up, seventeen patients were no longer on active duty military service. Eight patients had persistent bowel dysfunction and nine patients had persistent bladder dysfunction. Fifteen patients reported chronic low back pain. Seventeen were ambulating and five had documentation of running following surgery. CONCLUSIONS: This is the largest series of operatively managed LSD in patients currently reported. Our series suggests that combat-related LSD injuries frequently result in persistent, long-term neurologic dysfunction, disability, and chronic pain. Operative management carries a high postoperative risk of infection. However, a select group of patients are highly functional at latest follow-up.

Hydraulic distension of the knee: a novel treatment for arthrofibrosis after total knee replacement (case series).

BACKGROUND: Arthrofibrosis following total knee arthroplasty (TKA) is a common problem, which can be frustrating to both the patient and treating physician and can dramatically compromise post-operative function. Current treatment options for TKA arthrofibrosis include watchful waiting, injections, physical therapy, manipulation under anaesthesia, arthroscopic/open lysis of adhesions and revision surgery. We present a novel technique to treat acute and chronic stiffness following TKA, which we call hydraulic distension. METHODS: A retrospective pre- and post-operative inpatient and outpatient record review of three patients treated with hydraulic distension for arthrofibrosis following TKA at a single institution. RESULTS: Three patients with a mean age of 74 years (68-78) underwent hydraulic distension of the knee at a mean of 23.4 ± 18.4 months (9 weeks to 36 months) following primary TKA. The mean pre-distension maximum flexion was 86.7 ± 10.4°, and the mean post-distension flexion was 110 ± 13.2° (23.3° increase). The patients maintained a mean 110 ± 20° flexion (23.3° increase) at a mean follow-up of 11.7 months (1 week to 29 months). There were no complications. CONCLUSION: We present a novel technique for managing arthrofibrosis following TKA that has not been previously reported. This is an effective, safe procedure, with our patients experiencing a mean 23° increased knee flexion at the most recent follow-up.

Persistent axial neck pain after cervical disc arthroplasty: a radiographic analysis.

BACKGROUND CONTEXT: There is very little literature examining optimal radiographic parameters for placement of cervical disc arthroplasty (CDA), nor is there substantial evidence evaluating the relationship between persistent postoperative neck pain and radiographic outcomes. PURPOSE: We set out to perform a single-center evaluation of the radiographic outcomes, including associated complications, of CDA. DESIGN: This is a retrospective review. PATIENT SAMPLE: Two hundred eighty-five consecutive patients undergoing CDA were included in the review. OUTCOME MEASURES: The outcome measures were radiological parameters (preoperative facet arthrosis, disc height, CDA placement in sagittal and coronal planes, heterotopic ossification [HO] formation, etc.) and patient outcomes (persistent pain, recurrent pain, new-onset pain, etc.). METHODS: We performed a retrospective review of all patients from a single military tertiary medical center from August 2008 to August 2012 undergoing CDA. Preoperative, immediate postoperative, and final follow-up films were evaluated. The clinical outcomes and complications associated with the procedure were also examined. RESULTS: The average radiographic follow-up was 13.5 months and the rate of persistent axial neck pain was 17.2%. For patients with persistent neck pain, the rate of HO formation per level studied was 22.6%, whereas the rate was significantly lower for patients without neck pain (11.7%, p=.03). There was no significant association between the severity of HO and the presence of neck pain. Patients with a preoperative diagnosis of cervicalgia, compared to those without cervicalgia, were significantly more likely to experience continued neck pain postoperatively (28.6% vs. 13.1%, p=.01). There were no differences in preoperative facet arthrosis, pre- or postoperative disc height, segmental range of motion, or placement of the device relative to the posterior edge of the vertebral body.However, patients with implants more centered between the uncovertebral joints were more likely to experience posterior neck pain (p=.03). CONCLUSIONS: We found that posterior axial neck pain is relatively frequent after CDA, and patients with persistent neck pain were significantly more likely to have preoperative cervicalgia and develop HO postoperatively. We also found that patients with implants that were placed off-centered were less likely to also complain of neck pain, although the reasons for this finding remain unclear.

Reoperation after in-theater combat spine surgery.

BACKGROUND CONTEXT: The ideal timing of surgical decompression or stabilization following combat-related spine injury remains unclear. PURPOSE: The study aims to determine the etiology and factors related to reoperation following evacuation to the United States after undergoing in-theater spine surgery. STUDY DESIGN: This is a retrospective analysis. PATIENT SAMPLE: The sample includes 13 patients with combat-related spine injuries undergoing revision spine surgery. OUTCOME MEASURES: The outcome measures were time to arrival in the United States, time to reoperation, indications for revision, operative details, further revision surgery, infection rate, complications after reoperation, and most recent clinical follow-up information. METHODS: This is a retrospective analysis of patients undergoing spine surgery designated as injured during the Global War on Terrorism between July 2003 and July 2013. Inpatient and outpatient medical records, operative reports, and imaging studies were reviewed. RESULTS: The mean time to index surgery was 1.6 days. The mechanisms of injury included five gunshot wounds, three improvised explosive devices (IED), two helicopter crashes, one motor vehicle accident, and two other mechanisms (fall and crush injury). The mean injury severity score (ISS) was 22.7 (range: 13-45). There were six cervical, seven thoracic, eight lumbar, and two sacral injuries, with a mean of 1.8±1.0 spinal regions injured per patient. Twelve patients had a spinal cord injury, four of which were AIS (American Spinal Association Impairment Scale). Three patients underwent spinal stabilization on the date of injury, and one patient had three separate spine surgeries while downrange before arrival. Four patients underwent fixation in theater. There was a mean of 5.5 days from injury to arrival in the United States, and the mean time to revision fixation was 11.2 days post-index surgery (range: 4-14 days). Revision indications included instability or progressive kyphosis (N=6), and two of these patients had decompression without instrumentation downrange. Other indications included inadequate decompression (N=4), infection, persistent drainage, and epidural hematoma. At a mean of 5.5-year follow-up, all patients were medically retired from service, with minimal neurologic improvement. CONCLUSIONS: Our study found that instability or progressive kyphosis and incomplete decompression were the most common indications for reoperation after evacuation to the United States. Our data provide additional understanding of the potential etiologies of failure and reoperation following in-theater combat spine surgery, and may help avoid such complications.

The Use of Intravenous Tranexamic Acid in Patients Undergoing Total Hip or Knee Arthroplasty: A Retrospective Analysis at a Single Military Institution.

OBJECTIVE: To describe a single institution's experience after initiation of a protocol in which all primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) patients were administered intravenous tranexamic acid (TXA) intraoperatively to decrease perioperative blood loss. METHODS: A retrospective review of medical records at a single institution from February 2012 to April 2014. The TXA treatment group was compared to a control group. We reviewed intraoperative blood loss, preoperative hemoglobin (Hb) levels, postoperative day 0 to 2 Hb levels, transfusion rates, postoperative venous thromboembolism, and other complication rates. RESULTS: 259 patients underwent either TKA (165) or THA (94). 121 received perioperative intravenous TXA and 138 did not. There was a statistically decreased rate of allogeneic blood transfusion (0 vs. 10, p = 0.003) as well as a higher postoperative day 2 Hb level (10.8 ± 1.1 vs. 10.2 ± 2.6 g/dL, p = 0.02) in the treatment group. There was no statistical difference in any variable measured in the THA group, though there was a trend toward higher postoperative Hb levels at all-time points measured. CONCLUSION: Intravenous TXA is a safe and effective drug to decrease perioperative blood loss and allogeneic transfusion in THA and TKA. There was no increased risk of venous thromboembolism or other complications in our review.

An Analysis of Research from Faculty at U.S. Adult Reconstruction Fellowships.

We reviewed all articles published in three major orthopaedic journals from January 2010 to December 2014. Any article focusing on adult reconstruction of the hip or knee was reviewed for first and last authorship, institution, and level of evidence. Three institutions had authored work from arthroplasty faculty that fell within the top five most published institutions in all three journals, while one institution ranked first in all three journals. 43 of 67 (64.2%) reconstruction fellowships had at least one publication included in this study. The majority of the adult reconstruction literature published by faculty at U.S. reconstruction fellowships stems from a few academic centers with the ten most prolific institutions accounting for 65.9% of all U.S. fellowship publications.

Outcomes After Operative Management of Combat-Related Low Lumbar Burst Fractures.

STUDY DESIGN: Retrospective review. OBJECTIVE: Report the 2-year operative and clinical outcomes of these service members with low lumbar fractures. SUMMARY OF BACKGROUND DATA: The majority of spinal fractures occur at the thoracolumbar level, with fractures caudal to L2 accounting for only 1% of spine fractures. A previous report from this institution regarding combat-related spine burst fractures documented an increased incidence of low lumbar burst fractures in injured service members. METHODS: Review of inpatient and outpatient medical records in addition to radiographs for all patients treated at our institution with combat-related burst fractures occurring at the L3-L5 levels. RESULTS: Twenty-four patients with a mean age of 28.1± 7.2 underwent surgery for low lumbar (L3-L5) burst fractures. The mean number of thoracolumbar levels injured was 2.9 ± 1.4. Eleven patients had neurological injury, 4 of which were complete. The mean days to surgery were 16.8 ± 24.5. The mean number of levels fused was 4.3 ± 2.1, with fixation extending to the pelvis in 4 patients (17%). Fourteen (61%) patients had at least 1 postoperative complication, with 7 (30%) requiring reoperation. Five patients had a postoperative wound infection. Five patients had deep venous thromboses, 3 had pulmonary emboli. Mean clinical follow-up was 3.3± 2.2 years. At latest follow-up, all were separated from military service, 10 experienced persistent bowel/bladder dysfunction, 15 had lower extremity motor deficits, and 10 had documented persistent low back pain. Nineteen had chronic pain with 18 patients still taking pain medications and/or muscle relaxers. CONCLUSION: Low lumbar burst fractures are a rare injury with an increased incidence in combat casualties engaged in the wars in Iraq and Afghanistan. We found a high rate of acute postoperative complications (61%), as well as a high reoperation rate (30%). At approximately 3 years of follow-up, most of these patients had persistent neurological symptoms and chronic pain. LEVEL OF EVIDENCE: 4.

Treatment of symptomatic intraosseous pneumatocyst using intraoperative navigation.

Intraosseous pneumatocysts are benign air-containing lesions that are most often found in the spine and pelvis and are nearly always treated nonoperatively. Although rarely clinically symptomatic, studies have shown pneumatocysts to be present in up to 10% of computed tomography (CT) scans of the pelvis and spine. Radiographic characteristics of these lesions include a localized collection of gas with a thin sclerotic rim, no bony destruction, no soft tissue masses, and no medullary abnormalities. Computed tomography is the diagnostic study of choice, with Hounsfield units ranging from -580 to -950, showing a gas-containing lesion. Few studies have described the management of symptomatic pneumatocysts, and all reported cases concern underwater divers, presumably because of greater pressure cycling and barotrauma encountered while underwater diving. The goal of this report is to describe the intraoperative CT-guided navigation and percutaneous injection of calcium sulfate-calcium phosphate composite bone graft substitute material for the treatment of a symptomatic pneumatocyst in the ilium of a Navy dive instructor. The patient reported a 1-year history of increasing buttock pain with increased depth of diving, consistently reproduced by diving past a depth of 20 to 30 feet. To the authors' knowledge, this is the first description in the English literature of the operative treatment of an intraosseous pneumatocyst of the ilium. The use of intraoperative CT guidance permitted accurate percutaneous localization, decompression, and filling of the lesion with synthetic bone graft substitute, with complete early relief of symptoms. At 6-month follow up, the patient had reached diving depths of 170 feet without pain.