Faculty Bibliography

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.

A total of 96 displaced tibial plateau fractures in 94 patients (average age, 48 years) were treated with open reduction and internal fixation. At 12 months postoperatively, mean range of knee motion was 126 degrees and 10 (10%) of the patients had required a secondary surgery. Using a binary regression model, no demographic variable such as age, gender, smoking history, diabetes, BMI; or fracture characteristic such as mechanism of injury, initial plateau depression, Schatzker classification was identified that correlated with short-term functional outcome such as a complication, range of motion, healing time, or residual depression. We determined that radiographic fracture reduction was not superior following fractures with less initial displacement, and increased plateau collapse at 12 months postoperatively was not indicative of decreased function. However, an increased postoperative articular step-off was found to be associated with an increased risk of plateau collapse (p < 0.01). Furthermore, at 12 months, 76% of the patients had returned to their preinjury employment and the overall complication rate was 13%.

BACKGROUND: The recognition of the importance of femoro-acetabular impingement (FAI) as a potential cause of hip pain has been stimulated by major efforts to salvage hip joints by reconstruction to prevent or delay the need for replacement. A previous review addressed the nature of FAI, the various types, and how to make the diagnosis. When FAI occurs, the structure between the femur and acetabular rim, the labrum, is initially impinged upon and subsequently injured. METHOD: Injury to the labrum should be recognized when treating the osseous causes of FAI. Preserving or recovering labral function, enhancing hip stability and protecting the articular surface, is critical to restoring the hip to normal or near-normal mechanical and physiologic function. The present review collected the varied essential information about the labrum in a succinct manner, independent of treatment algorithms. RESULTS/CONCLUSION: Advanced knowledge of the labrum is presented, including the anatomy, circulation, histology, embryology, and neurology, as well as how the labrum tears, the types of tears, and how to make the diagnosis. The advantages and limitations of diagnostic magnetic resonance techniques are discussed, including magnetic resonance imaging (MRI), indirect magnetic resonance arthrography (i-MRA), and direct magnetic resonance arthrography (d-MRA). The review recognizes the complexity of the labrum and provides a greater understanding of how the labrum is capable of stabilizing the joint and protecting the articular surface of the hip. This information will act as a guide in developing treatment plans when treating FAI.

BACKGROUND: Two-part proximal humerus fractures are common orthopedic injuries for which surgical intervention is often indicated. Choosing a fixation device remains a topic of debate. PURPOSE: The purpose of this study is to compare two methods of fixation for two-part proximal humerus fractures, locking plate (LP) with screws versus intramedullary nailing (IMN), with respect to alignment, healing, patient outcomes, and complications. To our knowledge, a direct comparison of these two devices in treating two-part proximal humerus fractures has never before been studied. We hope that our results will help surgeons assess the utility of LP versus IMN. METHODS: A retrospective chart review was performed on 24 cases of displaced two-part surgical neck fractures of the humerus. Twelve shoulders were treated using IMN fixation and 12 others were fixated with LP. Data collected included sociodemographic, operative details, and postoperative care and function. RESULTS: Radiographic comparison of fixation demonstrated an average neck-shaft angle of 124 degrees and 120 degrees in the IMN group and LP group, respectively. Adjusted postoperative 6-month follow-up range of motion was 134 degrees of forward elevation in the IMN group and 141 in the LP group. The differences in range of motion and in complication rates were not found to be significant. CONCLUSIONS: Our results suggest that either LP fixation or IMN fixation for a two-part proximal humerus fracture provides acceptable fixation and results in a similar range of shoulder motion. Although complication rates were low and insignificant between the two groups, a trend toward increased complications in the IMN group is noted.

PURPOSE: Nonunions of the upper and lower extremity have been associated with pain and functional deficits. Recent studies have demonstrated that healing of these nonunions is associated with pain relief and both subjective and objective functional improvement. The purpose of this study was to determine which patient and surgical factors correlated with successful healing of a nonunion following surgical intervention. METHODS: Between September 2004 and February 2008, all patients with a "long bone nonunion" presenting to our academic trauma service were enrolled in a prospective data base. Baseline functional, demographic and pain status was obtained. Follow-up was obtained at 3, 6, and 12 months following surgical intervention, with longer follow-up as possible. One hundred and thirty-four patients with a variety of fracture nonunions were operated on by four different fellowship trained trauma surgeons with experience ranging from 2 to 15 years and variable nonunion surgery loads. Patients were stratified into one of three groups: 1. Patients who healed following one surgical intervention, 2. those who healed following multiple surgical intervention, and 3. those who failed to heal (remain ununited or underwent amputation). Healing was determined radiographically and clinically. Complications were recorded. Logistic regression analysis was performed to assess the cor-relation between specific baseline and surgical characteristics and healing. RESULTS: A minimum of 1 year follow-up was available for all 134 patients. One hundred and one patients (76%) with a mean age of 50 years healed at a mean of 6 months (range, 3 to 16) after one surgery. Twenty-two patients (16%) with a mean age of 47 years, who required more than one intervention, healed their nonunions at a mean of 11 months (range, 4 to 23). Eleven patients (8%) with a mean age of 50 years failed to heal at an average of 12 months follow-up. Complication rates were 11%, 68%, and 100% respectively for those who healed following one procedure, multiple procedures, and those who never healed. Higher surgeon volume (greater than 10 cases per year) was associated with 85% increased healing rates (OR = 0.15, 0.05-0.47 CI). The presence of a postoperative complication was associated with a 9 times lower likelihood of successful union as well (OR = 9.0, 2.6-31.7 CI). Patient age, sex, BMI, initial injury mechanism, tobacco use, and initial injury characteristics did not correlate with failure to heal. CONCLUSION: Our data is similar to other studies assessing outcomes following other complex reconstructive procedures. It appears that more experienced (higher volume) reconstructive surgeons and the development of fewer postoperative complications is associated with greater success following repair of a long bone nonunion. Infection at any point during treatment is associated with failure to achieve successful union.

We conducted a study to evaluate the outcomes and complications of open reduction and internal fixation (ORIF) of 2-, 3-, and 4-part proximal humerus fractures using a standard management protocol with locking plates. Of 72 patients with acute proximal humerus fractures managed with ORIF and locking plates, 63 were available at the minimum follow-up of 1 year and met the inclusion criteria. At each follow-up, radiographs were reviewed for healing, hardware failure, osteonecrosis, shoulder range of motion, and DASH (Disabilities of the Arm, Shoulder, and Hand) scores; any complications were recorded. Mean age was 62 years and mean follow-up was 19 months. There were 12 two-part fractures, 42 three-part fractures, and 9 four-part fractures. Thirteen patients had complications. Mean shoulder forward elevation was 135; patients with complications had a significantly lower mean forward elevation (P=.002). DASH scores were significantly lower in patients without complications than in those with complications (P=.01). Although excellent outcomes can be achieved when locking plates are used to manage proximal humerus fractures, complications are possible. Physicians must weigh the functional outcome data when considering management options for these types of injuries.