Proximal tibial metaphyseal fractures with severe soft tissue injury: clinical and functional results at 2 years.

BACKGROUND: Controversy exists regarding management of proximal tibial metaphyseal fractures with severe soft tissue injury. It is unclear whether limb salvage or early amputation results in the best functional and clinical outcomes. QUESTIONS/PURPOSE: We hypothesized that in this group of patients, there is no difference in functional outcomes, complication rates, clinical outcomes, or objective physical function related to the treatment approach. METHODS: We used the LEAP study database to perform a retrospective comparative review of a subset of patients with proximal tibial metaphyseal fractures (AO/OTA 41A, B, and C) with associated severe soft tissue injuries comparing the outcomes of patients who were treated with either limb salvage or amputation. RESULTS: Although there were major differences in clinical and functional outcomes based on patients' sociodemographics at 2 years, no differences in clinical or functional outcomes were detected regardless of whether amputation or limb salvage was performed. Severity of soft tissue injury was more predictive of outcome than the surgical approach used. CONCLUSIONS: Sociodemographics and soft tissue injury severity are more important than treatment approach for predicting clinical and functional outcomes at 2 years in patients with proximal tibia metaphyseal fractures with severe soft tissue injury. LEVEL OF EVIDENCE: Level III, retrospective comparative study. See Guidelines for Authors for a complete description of levels of evidence.

Anatomic double-bundle anterior cruciate ligament reconstruction revision surgery.

With the increasing number of double-bundle anterior cruciate ligament (ACL) reconstructions being performed, revision cases are expected. This report describes the first 3 cases of revision double-bundle ACL surgeries performed at our institution. In 3 athletes in whom the ACL was previously reconstructed with an anatomic double-bundle technique, new traumatic events occurred and an ACL retear was diagnosed. In cases 1 and 2 the anteromedial (AM) bundle was completely torn and the posterolateral (PL) bundle was stretched and nonfunctional. In case 1 both bundles were reconstructed via the previous tunnels, and the AM and PL grafts were tensioned at 60 degrees of flexion and full extension, respectively. In case 2 the PL femoral tunnel was posterosuperior to the PL anatomic position. Therefore we drilled a third femoral tunnel and used the previous PL tunnel as our new AM tunnel. In case 3 the rupture pattern presented an intact and functional PL bundle and a midsubstance AM tear. We decided to revise only the AM bundle using the previous AM tunnels, which were anatomically positioned. This report shows that revision of anatomic double-bundle ACL reconstruction is reasonable to accomplish and that the principles of anatomy are essential as a guide to approaching each case.

Patient Perceptions and Current Trends in Internet Use by Orthopedic Outpatients.

BACKGROUND: Many studies have highlighted concerns about the completeness and quality of information found online and how this may affect patients' education about their medical problems. One aspect of internet usage that has received less attention in the literature, however, is patient perception of the information that is gathered online, and how patients use it related to their musculoskeletal care. QUESTIONS/PURPOSES: The objective of the study is to utilize a cross-sectional study design to describe internet usage and patient perceptions of orthopedic online information and to identify differences in usage patterns. METHODS: One thousand two hundred ninety-six questionnaires were distributed to consecutive patients at orthopedic outpatient clinics which consisted of questions pertaining to patients' internet use. Basic demographic data were collected, and subgroup analyses were performed to examine the effect of three variables (age, gender, and clinic type) on various outcomes. RESULTS: 84.9% of patients reported access to the internet. Of patients with internet access, 64.7% reported using the internet for obtaining orthopedic information. 43.1% of the respondents who searched for orthopedic information rated it as "very useful," 56.3% found it "somewhat useful," and 0.6% found it "not at all useful". Younger patients were more likely to have used the internet for health and orthopedic information and to have found this information either very or somewhat useful. Males were more likely to have found the internet information very useful. Overall, only 33.7% of patients who researched their current orthopedic complaint accessed the institutional website for information. CONCLUSION: A large proportion of patients use the internet to research orthopedic information and most patients, especially younger males, find the information useful.

Anatomic double-bundle anterior cruciate ligament reconstruction.

Anterior cruciate ligament (ACL) reconstruction is one of the most common procedures performed by orthopaedic surgeons. The procedure has improved significantly since its inception in 1900 and continues to be intensively studied with outcomes receiving considerable attention. Traditional ACL reconstruction techniques have focused on one portion of the ACL--the anteromedial bundle. Single-bundle ACL reconstruction is the criterion standard and has provided good to excellent results, with many athletes being able to return to sports; however, recently, some authors have noted persistent instability with functional testing and degenerative radiographic changes after single-bundle ACL reconstruction. As a result, several centers have attempted to improve upon the single-bundle technique by reconstructing both the anteromedial and posterolateral bundles of the ACL. This article will present the embryologic, anatomic, and biomechanical rationale for double-bundle ACL reconstruction. In addition, the latest outcomes of double-bundle ACL reconstruction will be presented.

Any Cortical Bridging Predicts Healing of Tibial Shaft Fractures.

BACKGROUND: There is no consensus regarding the optimal radiographic criteria for predicting the final healing of fractures. The purpose of this study was to determine if the time to the radiographic appearance of cortical bridging predicted the final healing of tibial shaft fractures, to examine the reliability of this assessment, and to determine when it is most accurate during the postoperative period. METHODS: We retrospectively reviewed the data on 176 tibial fractures (OTA [Orthopaedic Trauma Association] 42-A, B, and C) treated with intramedullary nailing at a level-I trauma center from 2007 through 2010. Postoperative radiographs were assessed for varying degrees of cortical bridging, and interobserver reliability was calculated. Receiver operating characteristic (ROC) curve and chi-square analyses determined the accuracy of cortical bridging assessments in predicting union. RESULTS: The nonunion rate was 7%. Any cortical bridging within four months was an excellent predictor of final healing (accuracy = 99%, area under the curve [AUC] = 0.995, p < 0.0001) and was the most reliable criterion (kappa = 0.90). All fractures that showed unicortical bridging eventually showed bridging of three cortices without additional intervention. CONCLUSIONS: Assessment for any cortical bridging by four months postoperatively is a reliable, accurate predictor of tibial shaft fracture-healing. This relatively early radiographic finding discriminates between fractures that will undergo late union with observation alone and those destined for nonunion. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Genomewide molecular and biologic characterization of biomembrane formation adjacent to a methacrylate spacer in the rat femoral segmental defect model.

OBJECTIVES: This study focuses upon the morphologic and molecular features of the layer of cells, termed the "biomembrane," which forms around methacrylate spacers in bone segmental defects. The objective of this research was to assess the biomembrane formed in a novel rodent femoral segmental defect model at 4, 8, and 16 weeks with histologic and molecular studies. METHODS: Following Institutional Animal Care and Use Committee approval, a segmental defect was created in the rat femur and stabilized with the AO LockingRatNail and analyzed at 4, 8, and 16 weeks postsurgery using digital radiologic imaging, morphological and immunohistochemical studies, and genomewide gene expression studies employing microarray analysis. RESULTS: The biomembrane formed around the methacrylate spacer was rich in vasculature, which showed vascular endothelial growth factor immunolocalization. The biomembrane supported development of foci of bone and cartilage within it. Bone morphogenetic protein 2 immunolocalization and gene expression were positive within developing osseous and chondrocyte foci. Microarray analysis showed significant expression of key genes related to bone and cartilage formation and angiogenesis. CONCLUSIONS: This rat bone model was effective in creation of the biomembrane. Bone and cartilage foci were formed within the vascularized biomembrane with associated expression of genes critical for bone and cartilage development/formation and vascularization. The polymethyl methacrylate-induced biomembrane offers an exciting potential solution for segmental defects; the biomembrane, may act as a receptive bed and also serve as a source for mesenchymal stem cells, which could be recruited/directed for the healing process.

Recombinant human bone morphogenetic protein-2 use in the off-label treatment of nonunions and acute fractures: a retrospective review.

BACKGROUND: Recombinant human bone morphogenetic protein-2 (BMP-2) is Food and Drug Administration-approved for use in acute open tibial shaft fractures. Some surgeons, however, also use BMP-2 in an "off-label" application for other acute fractures and for nonunion care. This retrospective study was performed to assess radiographic outcomes of off-label uses of BMP-2 for acute fractures and nonunions at our institution. METHODS: All eligible off-label BMP-2 applications between 2004 and 2008 for acute fractures or nonunions were reviewed. Univariate and multivariate analyses were completed to identify patient and clinical factors that could predict radiographic success or failure of the procedure. RESULTS: One hundred sixteen of 145 BMP-2 applications in 104 of 128 patients met inclusion and exclusion criteria. The overall radiographic union rate was 66% (76 of 116). In the univariate analysis, five factors correlated with significantly higher union rate: volume of bone defect <4 cm3, >2 cortices in contact at the index procedure, male gender, body mass index <30, and history of closed fracture pattern. Within the multivariate analysis, factors independently predictive of radiographic union included open versus closed fracture, gender, and volume of bone defect. CONCLUSION: Off-label use of BMP-2 in acute fractures and nonunions resulted in a 66% success rate. It remains uncertain whether there is any clinical advantage to this approach, but it appears that female gender, open injury, and higher volumes of bone defect may be important negative prognostic factors for obtaining radiographic union. Appropriately powered prospective randomized trials are needed for further clarification, especially in light of the high cost of this treatment.

Utilization of the AO LockingRatNail in a novel rat femur critical defect model.

BACKGROUND: Our objective was to utilize a commercially available rodent locked intramedullary nail in a rat femur diaphyseal defect. This model is needed for future studies where materials in the critical defect could be modified with agents to fight infection (antibiotics) or promote osteogenesis. METHODS: After unsatisfactory attempts to develop a reliable femur critical size defect model utilizing various forms of fixation, a locked intramedullary nailing system (AO LockingRatNail) was employed in 105 male Sprague Dawley rats. A 5 mm critical size mid-diaphyseal femoral defect was created using a pneumatic sagittal saw. The intramedullary nail was placed in the femur in a retrograde manner. A prefabricated polymethyl-methacrylate (PMMA) spacer was utilized to fill the defect. Once adequate alignment was achieved, two locking pegs were placed (one distal, one proximal) to provide stable fixation. RESULTS: The technique was successful in 90% of femurs (95 of 105). The majority of complications centered on failure of the placement of locking pegs (7 of 10). One rat presented with migration of the nail out of the knee. Two rats presented with fractures not recognized intraoperatively. These complications occurred early in the study and decreased as surgical experience increased. Surgery was tolerated well by the rats as reflected by significant weight postoperative gain (p < .001). CONCLUSIONS: The AO LockingRatNail is a novel, reproducible, and successful method for stabilization of critical size femoral diaphyseal defects in the rat. This model has future value in the examination of the biological processes involved in the healing of critical bone defects.

Quality and content of Internet-based information for ten common orthopaedic sports medicine diagnoses.

BACKGROUND: Although the use of the Internet to access health information has grown quickly, the emergence of quality controls for health information web sites has been considerably slower. The primary objective of this study was to assess the quality and content of Internet-based information for commonly encountered diagnoses within orthopaedic sports medicine. METHODS: Ten common diagnoses within the scope of orthopaedic sports medicine were chosen. Custom grading templates were developed for each condition, and they included an assessment of web-site type, the accountability and transparency of the information (Health On the Net Foundation [HON] score), and the information content. Information content was divided into five subcategories: disease summary, pathogenesis, diagnostics, treatment and complications, and outcomes and prognosis. Two popular search engines were used, and the top ten sites from each were independently reviewed by three authors. Data were evaluated for interobserver variability, HON scores, information content scores, and subgroup score comparisons. RESULTS: After eliminating duplicate sites, a total of 154 unique sites were reviewed. The most common web-site types were commercial (seventy-four sites) and academic (thirty-two sites). Average HON scores, on a 16-point scale, were 9.8, 9.5, and 8.5, for reviewers 1, 2, and 3, respectively. Average information content scores, on a 100-point scale, were 56.8, 56.0, and 54.8 for reviewers 1, 2, and 3, respectively. Average content scores in each subgroup ranged between 45% and 61% of the maximum possible score. The presence of the HONcode seal was associated with significantly higher HON (p = 0.0001) and content scores (p = 0.002). CONCLUSIONS: The quality and content of health information on the Internet is highly variable for common sports medicine topics. Patients should be encouraged to exercise caution and to utilize only well-known sites and those that display the HONcode seal of compliance with transparency and accountability practices.

A biomechanical evaluation of ulnar collateral ligament reconstruction using a novel technique for ulnar-sided fixation.

BACKGROUND: Techniques for ulnar collateral ligament (UCL) reconstruction have evolved since its original description. HYPOTHESIS: Ulnar collateral ligament reconstruction using the ZipLoop for ulnar-sided fixation, as combined with the humeral docking technique supplemented with an interference screw, will restore valgus stability similar to that of the Jobe technique and the native ligament. STUDY DESIGN: Controlled laboratory study. METHODS: Kinematic testing was performed on 8 matched pairs of cadaver elbows with an electromagnetic tracking system through an arc of motion for the intact, disrupted, and reconstructed states of the UCL in an unloaded and loaded condition. From each pair, the docking technique using the ZipLoop for ulnar fixation and humeral docking technique supplemented with an interference screw and the traditional Jobe technique were performed with matched gracilis allograft tendons. After kinematic testing, both reconstruction groups were tested to failure at 70 degrees of flexion. RESULTS: Kinematic results for the unloaded condition showed that both reconstruction techniques significantly overcorrected (less valgus angulation) the specimens between 40 degrees and 120 degrees of flexion when compared with the intact ligament (all P values < .027). Under loaded conditions, the ulnar trajectories for both reconstruction techniques exhibited significantly greater valgus angulation (undercorrection) at 20 degrees of flexion (Jobe, P = .0084; ZipLoop, P = .0289) when compared with the intact ligament but were not significantly different over the remaining arc of motion. Failure testing resulted in no significant statistical difference between the 2 reconstruction groups. Failure testing demonstrated that humeral tunnel egress, midsubstance elongation, and ulnar tunnel egress of the ligament were similar between the reconstruction techniques. CONCLUSION: The docking technique using the ZipLoop for ulnar-sided fixation is biomechanically equivalent to the Jobe technique for UCL reconstruction. Both reconstruction techniques restore valgus stability similar to that of the native UCL ligament. CLINICAL RELEVANCE: This modification in the docking technique restores elbow kinematics while eliminating the risk of ulnar bone bridge fracture, and it allows for retensioning of the graft after cortical fixation.

MRI measurement of the 2 bundles of the normal anterior cruciate ligament.

Anatomical studies have shown that the normal anterior cruciate ligament (ACL) consists of 2 distinct functional bundles: the anteromedial and posterolateral bundles. To date, no study has assessed the magnetic resonance imaging (MRI) appearance of the anteromedial and posterolateral bundles. The purpose of this study was to measure the anteromedial and posterolateral bundles using high-field digital MRI. Fifty MRIs of the knees of 50 patients were prospectively collected using a 1.5-T magnet. The length and width of each ACL bundle was measured on sagittal and coronal digital MRIs, independently performed by 2 observers blinded to each other's measurements. The average length and width of the anteromedial and posterolateral bundles were determined for all patients. Intraclass correlation coefficients were calculated to determine intertester test-retest reliability. In the sagittal plane, the anteromedial bundle averaged 36.9+/-2.8 mm in length and 5.1+/-0.7 mm in width. The posterolateral bundle, by contrast, averaged 20.5+/-2.4 mm in length and 4.4+/-0.8 mm in width. In the coronal plane, the width of the anteromedial bundle averaged 4.2+/-0.8 mm and of the posterolateral bundle averaged 3.7+/-0.8 mm. Interobserver reliability for length of the ACL in the sagittal plane was 0.85, with a 95% CI of 0.75 to 0.91 for the anteromedial bundle and 0.75 with a 95% CI of 0.60 to 0.85 for the posterolateral bundle. Providing precise measurement of the ACL anteromedial and posterolateral bundles on MRI may improve the ability to detect damage to 1 or both of the bundles following injury.

Primary anatomic double-bundle anterior cruciate ligament reconstruction: a preliminary 2-year prospective study.

BACKGROUND: The anterior cruciate ligament consists of 2 functional bundles, the anteromedial bundle and the posterolateral bundle. Single-bundle anterior cruciate ligament reconstruction is the current standard for the treatment of anterior cruciate ligament deficiency. However, a significant subset of patients continues to report residual symptoms of instability after such reconstruction. HYPOTHESIS: Anatomic double-bundle anterior cruciate ligament reconstruction may more closely restore normal kinematics of the knee by reproducing the native anatomy. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We report the current clinical outcomes of the initial 100 consecutive patients who underwent anatomic double-bundle anterior cruciate ligament reconstruction with an average follow-up of 2.1 +/- 0.5 years. All patients were prospectively followed to document range of motion, ligamentous laxity, and functional strength, as well as activity and sports participation. RESULTS: Side-to-side difference in range of motion was 2 degrees +/- 3 degrees for extension and 2 degrees +/- 5 degrees for flexion. Sixty-five percent of patients had a normal Lachman test result, and 33% were nearly normal. For the pivot-shift test findings, 94% were normal, and 6% were nearly normal. The average side-to-side difference in the KT-2000 arthrometer test was 1.0 +/- 2.3 mm. There were 8 graft failures, 7 of which had subsequent revision surgery. No patients reported pain, swelling, or instability during activities of daily living, and 73% to 78% had no symptoms during very strenuous or strenuous sports activities. The scores of the International Knee Documentation Committee Subjective Knee Form, Activities of Daily Living, and Sports Activity Scores of the Knee Outcome Survey were 85.0, 91.8, and 87.0, respectively, and were similar compared with patients undergoing single-bundle anterior cruciate ligament reconstruction, which we have previously reported. Fifty-one percent described their current activity level as normal, and 35% reported it as nearly normal. CONCLUSION: Anatomic double-bundle anterior cruciate ligament reconstruction results in good restoration of joint stability and patient-reported outcomes when evaluated 2 years after surgery.

Assessment of normal ACL double bundle anatomy in standard viewing planes by magnetic resonance imaging.

Anatomical studies show that the native ACL consists of two distinct functional bundles, termed the anteromedial (AM) and posterolateral (PL) bundles. The utility of using routine magnetic resonance imaging (MRI) to distinguish the individual bundles of the ACL has not been evaluated. The purpose of this study was to evaluate the intra- and inter-observer agreement for assessment of the AM and PL bundles using MRI in the axial, coronal, and sagittal viewing planes. We identified a series of patients seen in the senior author's clinic during a 16-month period. Images were independently evaluated in blinded fashion at two separate time points by a musculoskeletal radiologist and two orthopaedic residents. The AM bundle was detected in most planes of view with high frequency and reliability, while detection of the PL bundle was less frequent and had a lower associated reliability. Our results indicate that it is difficult to reliably detect both the AM and PL bundles using a low-field strength magnet with standard planes of view. It has been demonstrated that the ACL may be imaged effectively in planes that are based on the natural course of the ligament, and it is likely that this will also facilitate visualization of the individual AM and PL bundles. The use of additional oblique planes of view offers a potential approach for improved evaluation of the ACL, even with low field strength magnets. Future work in this area may assist in the pre-operative assessment of isolated AM or PL bundle injuries, facilitating a more anatomic approach to ACL reconstruction.