Faculty Bibliography

OBJECTIVES: To evaluate the relationship between mechanism of injury and mortality in geriatric trauma patients and the ability of existing injury severity indices (ISIs) to assess mortality. DESIGN: Retrospective review. SETTING: Urban level 1 trauma center. PARTICIPANTS: Four thousand five hundred forty-five trauma patients age >/=55 presenting between 2008 and 2011. INTERVENTION: Low-energy (LE-GTP) and high-energy (HE-GTP) geriatric trauma patient cohorts were created based on ICD-9 injury codes. Existing ISIs were evaluated for their ability to predict in-hospital mortality using the area under the receiver-operating characteristic curve (AUROC). MAIN OUTCOME MEASURES: Mortality. RESULTS: The Trauma Score-Injury Severity Score (TRISS) was the most predictive ISI for both cohorts and was deemed to have moderate predictive capacity (AUROC: 0.82) in LE-GTP and excellent predictive capacity (AUROC: 0.91) in the HE-GTP. For, HE-GTP each 1-year increase in age was associated with a 12% increase risk of mortality versus 6% for LE-GTP. Preexisting conditions (PECs) were distributed differently between the cohorts with significantly more PECs in the LE-GTP (P < 0.01). CONCLUSIONS: Existing ISIs have fair-to-moderate predictive capacity for in-hospital morality in LE-GTPs and moderate-to-excellent predictive capacity in HE-GTPs. LE-GTPs and HE-GTPs are distinct cohorts that should be evaluated separately. Combining the cohorts underestimates both the effect of age on HE-GTPs and the effect of PECs on LE-GTPs while overestimating the effect of PECs on HE-GTPs. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Today's increasingly complex health-care landscape requires that physicians take an active role in minimizing health-care costs and expenditures. Judicious choice of implants, a fracture-driven treatment algorithm, capitation models, use of generic fracture implants, and reuse of external fixation constructs all represent mechanisms that can result in substantial savings. In some health-care environments, these cost savings programs may be directly linked to physician reimbursement in the form of gainsharing plans. Evidence-based critical evaluations of implant usage patterns are necessary to help control implant-related health-care spending but are lacking in the current literature. Physicians need to acknowledge their influence and responsibility in this realm and assume an active role to help reduce costs.

INTRODUCTION: Elderly patients are at risk of fracture nonunion, given the potential setting of osteopenia, poorer fracture biology, and comorbid medical conditions. Risk factors predicting fracture nonunion may compromise the success of fracture nonunion surgery. The purpose of this study was to investigate the effect of patient age on clinical and functional outcome following long bone fracture nonunion surgery. MATERIALS AND METHODS: A retrospective analysis of prospectively collected data identified 288 patients (aged 18-91) who were indicated for long bone nonunion surgery. Two-hundred and seventy-two patients satisfied study inclusion criteria and analyses were performed comparing elderly patients aged >/=65 years (n = 48) with patients <65 years (n = 224) for postoperative wound complications, Short Musculoskeletal Functional Assessment (SMFA) functional status, healing, and surgical revision. Regression analyses were performed to look for associations between age, smoking status, and history of previous nonunion surgery with healing and functional outcome. Twelve-month follow-up was obtained on 91.5% (249 of 272) of patients. RESULTS: Despite demographic differences in the aged population, including a predominance of medical comorbidities (P < .01) and osteopenia (P = .02), there was no statistical differences in the healing rate of elderly patients (95.8% vs 95.1%, P = .6) or time to union (6.2 +/- 4.1 months vs. 7.2 +/- 6.6, P = .3). Rates of postoperative wound complications and surgical revision did not statistically differ. Elderly patients reported similar levels of function up to 12 months after surgery. Regression analyses failed to show any significant association between age and final union or time to union. There was a strong positive association between smoking and history of previous nonunion surgery with time to union. Age was associated (positively) with 12-month SMFA activity score. CONCLUSIONS: Smoking and failure of previous surgical intervention were associated with nonunion surgery outcomes. Patient's age at the time of surgery was not associated with achieving union. Advanced age was generally not associated with poorer nonunion surgery outcomes.

BACKGROUND: The purpose of this study was to compare the functional outcomes and quality of life of older and younger patients with similarly treated distal femur fractures. METHODS: We conducted an assessment of 57 patients who sustained distal femur fractures (Orthopaedic Trauma Association Type 33B, C) and underwent surgical treatment at our academic medical center. Patients were divided into 2 groups for analysis: an elderly cohort of patients aged 65 or older and a comparison cohort of patients younger than age of 65. A retrospective review of demographics, preoperative ambulatory status, radiographic data, and physical examination data was collected from the medical records. Follow-up functional data were collected via telephone at a mean of 2.5 years (range 6 months-8 years) using a Short Musculoskeletal Functional Assessment (SMFA). All patients underwent standard operative treatment of either nail or plate fixation. RESULTS: There was no statistical difference in gender, fracture type, surgical technique, surgeon, or institution where the surgery was performed. The percentage of patients with healed fractures at 6-months follow-up was not significantly different between the cohorts. The elderly cohort had slightly worse knee range of motion at 3, 6, and 12 months postoperatively but there was not a statistically significant difference between the groups. The SMFA Daily Activity, Functional, and Bother indices were significantly worse in the older cohort (P < .01, P = .01, P = .02, respectively). However, there was no significant difference in the SMFA Emotional or Mobility indices. CONCLUSION: Despite lower quality of life and functional scores, this study suggests that relatively good clinical outcomes can be achieved with surgical fixation of distal femoral fractures in the elderly patients. Age should not be used as a determinate in deciding against operative treatment of distal femur fractures in the elderly patients.

Open knee joint injuries are potentially devastating injuries if not properly diagnosed and treated. Current diagnostic techniques, such as the saline load test (SLT), are based on outdated literature. Diagnosis of traumatic arthrotomies via the presence of intra-articular air on computed tomography (CT) scan has recently been shown to be 100% sensitive and specific to detect these injuries. Additionally, open knee joint injuries have a high rate of associated periarticular fractures (51%). The workhorse open surgical approach to the knee is the medial parapatellar approach; however, arthroscopic irrigation and debridement (I&D) should be considered in the setting of small puncture wounds (e.g., gunshot wounds). Antibiotic therapy following I&D of an open knee joint injury includes 24 to 48 hours of intravenous antibiotics. Oral antibiotic therapy can be administered afterwards for 3 to 5 days if the original injury was grossly contaminated. Ultimately, a unified management algorithm for open knee joint injuries based on current literature should be followed to ensure appropriate diagnosis and treatment of this potentially devastating injury.

OBJECTIVE:: To 1) determine the incidence and injury profile of open periarticular fractures about the knee joint in a cohort of patients presenting to the emergency department with a deep periarticular knee wound and to 2) determine the effectiveness of CT scan to detect and guide management of these open fractures compared to plain radiographs. DESIGN:: Retrospective Review SETTING:: Level I trauma center PATIENTS/PARTICIPANTS:: 78 patients (79 knees) with deep periarticular knee wounds of which 62 patients (63 knees) received both a plain radiograph and a CT scan of the knee. INTERVENTION:: Plain radiograph and CT scan of the injured knee. MAIN OUTCOME MEASUREMENTS:: Comparison of OTA fracture classification and surgeon produced management plan as determined by plain radiographs versus CT scans. CT scan was considered the gold-standard test to detect a fracture. RESULTS:: Twenty-one (27%, 21/79) knees had an open periarticular fracture of the knee and 95% (20/21) of these knees had intra-articular air indicative of an associated traumatic arthrotomy. Of 41 (52%, 41/79) knees with a traumatic arthrotomy, 51% (21/41) had an associated open periarticular fracture of the knee. Plain radiographs detected 18 fractures in 17 knees (of which 1 fracture was later determined to not be a true fracture) whereas CT scan detected 26 fractures in 21 knees. Overall, CT scan detected 9 additional fractures in 6 knees. The specificity and sensitivity and positive predictive and negative predictive values of plain radiographs to detect and rule-out a fracture was 98%/65% and 94%/82%, respectively. Compared to plain radiographs, CT scan altered the fracture classification in 48% of patients and altered the management plan in 43% of patients, respectively. Gunshot wounds to the knee had a 48% (12/25) incidence of an associated open periarticular fracture compared to an 17% (9/54) incidence for all other injury mechanisms combined (p<.01). CONCLUSION:: Patients with a periarticular knee wound have a high incidence of open periarticular fractures, and the incidence is even higher if the mechanism of injury is a GSW or there is associated traumatic arthrotomy. CT scan improves detection and management of open fractures of the knee compared to plain radiographs. Consideration should be given to routinely using CT scan to evaluate knees with deep periarticular wounds that present to the ED, especially if secondary to gunshot injuries, given the high incidence open periarticular fractures of the knee. LEVEL OF EVIDENCE:: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

OBJECTIVE:: To report our experience with computed tomography (CT) scans to detect traumatic arthrotomies of the knee joint (TAK) based upon the presence of intra-articular air. DESIGN:: Retrospective review SETTING:: Level I trauma center PATIENTS/PARTICIPANTS:: Sixty-two consecutive patients (63 knees) underwent a CT scan of the knee in the emergency department and had a minimum of 14 days follow-up. Cohort of 37 patients (37 knees) from the original 62 patients who underwent a Saline Load Test (SLT) INTERVENTION:: CT scan and SLT MAIN OUTCOME MEASUREMENTS:: Positive traumatic arthrotomy of the knee (+TAK) was defined as operating room (OR) confirmation of an arthrotomy or no intra-articular air on CT scan (-iaCT) (and -SLT if performed) with follow-up revealing a septic knee. Periarticular wound equivalent to no traumatic arthrotomy (pw=(-TAK)) was defined as OR evaluation revealing no arthrotomy or -iaCT (and -SLT if performed) with follow-up revealing no septic knee. RESULTS:: All 32 knees with intra-articular air on CT scan (+iaCT) had OR confirmation of a TAK and none of these patients had a knee infection at a mean follow-up of 140.0+/-279.6 days. None of the 31 patients with -iaCT had a knee infection at a mean follow-up of 291.0+/-548.1 days. Based on these results, the sensitivity and specificity of the CT scan to detect +TAK and pw=(-TAK) was 100%. In a subgroup of 37 patients that received both a CT scan and the conventional SLT, the sensitivity and specificity of the CT scan was 100% compared to 92% for the SLT (p<0.001). CONCLUSION:: CT scan performs better than the conventional SLT to detect traumatic knee arthrotomies and identify periarticular knee wounds that do not require surgical intervention and should be considered a valid diagnostic test in the appropriate clinical setting. LEVEL OF EVIDENCE:: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

OBJECTIVES:: To determine the lowest estimated radiation dose necessary to reproducibly detect intra-articular air in the knee joint of a cadaver model. METHODS:: 10 adult fresh-frozen cadaver knees with intact joint capsules provided by Science Care(R), Phoenix, AZ. were thawed and scanned at 5 decreasing radiation doses (decreasing by approximately half from 8.42 mGy to 0.74 mGy) after introducing increasing volumes (0 cc, 0.1 cc, 0.3 cc, 0.5 cc, 0.7 cc, 0.9cc) of intra-articular air. Scans were performed using 2.0 mm slice-thickness from the distal 1/3 of the femur to the proximal 1/3 of the tibia. Sagittal and coronal reconstructions of each scan using 1.0 mm slice-thickness were rendered. All scans were reviewed by 1) a single attending radiologist, 2) a single attending orthopedic surgeon, and 3) a single chief resident, for the presence of intra-articular air. RESULTS:: The sensitivity and specificity of CT scan to detect intra-articular air at each volume of intra-articular air (0.1 cc, 0.3 cc, 0.5 cc, 0.7 cc, 0.9cc) was 100% at 0.74 mGy - the radiation threshold dose (RadTH) (scan parameters: voltage 80kV, current: 33mA, and scan time: 12.17 sec). The effective radiation dose at 0.74 mGy for a CT scan of the knee is approximately 0.10 mSV CONCLUSIONS:: CT scan to detect traumatic knee arthrotomies can be successfully accomplished at a threshold radiation dose of 0.74 mGy and for an intra-articular volume of 0.1cc of air. This low radiation dose protocol and volume of intra-articular air should be taken into consideration with future studies evaluating the use of CT scan to detect traumatic arthrotomies.

OBJECTIVE:: To describe the use of the Saline Load Test (SLT) utilizing a new definition that more adequately characterizes its use in the emergency department (ED) setting. DESIGN:: Retrospective review SETTING:: Level I trauma center PATIENTS/PARTICIPANTS:: Fifty consecutive patients who underwent a SLT of the knee in the emergency department and had a minimum of 14 days follow-up. INTERVENTION:: Saline Load Test MAIN OUTCOME MEASUREMENTS:: Positive traumatic arthrotomy of the knee (+TAK) defined as OR confirmation of an arthrotomy (assumed to develop a septic knee) or -SLT with follow-up revealing a septic knee. Periarticular wound equivalent to no traumatic arthrotomy of the knee (pw=(-TAK)) defined as OR evaluation revealing no arthrotomy (assumed not to develop a septic knee) or -SLT whose follow-up revealed no septic knee. Development of a septic knee was considered the gold-standard for determining true positives/negatives and false positives/negatives. RESULTS:: The mean wound size was 3.9 +/- 4.3 cm and the mean saline load volume was 74.9 +/- 28.2 cm. There were 19 +SLTs of which there were 16 +TAK and 3 pw=(-TAK). The 3 pw=(-TAK) in the +SLT group were evaluated in the OR where inspection of the joint capsule revealed the absence of a traumatic arthrotomy. There were 31 -SLTs of which there were 1 +TAK and 30 pw=(-TAK). The SLT has a sensitivity of 94% and a specificity of 91% for detecting +TAKs and ruling-out periarticular wounds not requiring surgical intervention (pw=(-TAK)). The false-positive rate of the SLT to detect +TAK is 9%. CONCLUSION:: Using +TAK and pw=(-TAK) as the newly defined measures of the SLT, we report the sensitivity (94%) and specificity (91%) of the SLT in the ED setting while still maintaining the clinical relevancy of the test. Based on a small sample size, knees with small periarticular wounds and a -SLT and no other radiographic or clinical evidence of an arthrotomy appear to have an infection rate of 0% with non-operative management. LEVEL OF EVIDENCE:: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Wire breakage and migration is a known complication of using a wire tension band construct to treat displaced patella fractures. We report a case of a broken K-wire that migrated from the patella completely into the proximal tibia without complication 9 years after the index surgery. This report highlights the fact that wire migration can occur long after fracture healing and be relatively asymptomatic. But because the complications of wire migration can be deadly, it requires diligence on the part of the physician to educate the patient that new knee pain after operative fixation requires formal evaluation by the treating surgeon.