Amit M. Momaya

Risk factors for infection after operative fixation of Tibial plateau fractures.

INTRODUCTION Tibial plateau fractures are challenging to treat due to the high incidence of postoperative infections. Treating physicians should be aware of risk factors for postoperative infection in patients who undergo operative fixation. PATIENTS AND METHODS A retrospective review was undertaken to identify all patients with tibial plateau fractures over a 10 year period (2003-2012) who underwent open reduction internal fixation. A total of 532 patients were identified who met the inclusion criteria. Several patient and clinical characteristics were recorded, and those variables with a significant association (p<0.05) with postoperative infection after a univariate analysis were further analyzed using a multivariate analysis. RESULTS Fifty-nine (11.1%) of the 532 patients developed a deep infection. The average length of follow-up for patients was 19.5 months. Methicillin-resistant Staphylococcus aureus was the most common species, and it was isolated in 26 (44.1%) patients. Open fractures, the presence of compartment syndrome, and a Schatzker type IV-VI were found to be independent risk factors for deep infection. CONCLUSIONS The rate of deep infection remains high after operative fixation of tibial plateau fractures. Patients with risk factors for infection should be counseled on the possibility of reoperation, and surgeons should consider MRSA prophylaxis in those patients who are at higher risk.

Biomechanical Comparison of Volar Fixed-Angle Locking Plates for AO C3 Distal Radius Fractures: Titanium Versus Stainless Steel With Compression.

PURPOSE To determine biomechanical differences between a fixed-angle locking volar titanium plate (VariAx; Stryker, Kalamazoo, MI) and a fixed-angle compression locking volar stainless steel plate (CoverLoc Volar Plate; Tornier, Amsterdam, Netherlands) in the fixation of simulated AO C3 distal radius fractures. METHODS Eighteen cadaveric upper extremities (9 matched pairs) with an average age of 54 years were tested. A 4-part AO C3 fracture pattern was created in each specimen. The fractures were reduced under direct vision and fixed with either the fixed-angle locking volar titanium plate or the fixed-angle compression locking volar stainless steel plate. Motion tracking analysis was then performed while the specimens underwent cyclic loading. Changes in displacement, rotation, load to failure, and mode of failure were recorded. RESULTS The fragments, when secured with the fixed-angle compression locking stainless steel construct, demonstrated less displacement and rotation than the fragments secured with the fixed-angle locking titanium plate under physiological loading conditions. In the fixed-angle compression locking stainless steel group, aggregate displacement and rotation of fracture fragments were 5 mm and 3° less, respectively, than those for the fixed-angle locking titanium group. The differences between axial loads at mechanical failure and stiffness were not statistically significant. The compression locking stainless steel group showed no trend in mode of failure, and the locking titanium plate group failed most often by articular fixation failure (5 of 9 specimens). CONCLUSIONS The fixed-angle compression locking stainless steel volar plate may result in less displacement and rotation of fracture fragments in the fixation of AO C3 distal radius fractures than fixation by the fixed-angle locking volar titanium plate. However, there were no differences between the plates in mechanical load to failure and stiffness. CLINICAL RELEVANCE Fixation of distal radius AO C3 fracture patterns with the fixed-angle compression locking stainless steel plate may provide improved stability of fracture fragments.

The Cost-Effectiveness of Anterior Cruciate Ligament Reconstruction in Competitive Athletes

Background: Competitive athletes value the ability to return to competitive play after the treatment of anterior cruciate ligament (ACL) injuries. ACL reconstruction has high success rates for return to play, but some studies indicate that patients may do well with nonoperative physical therapy treatment. Purpose: To evaluate the cost-effectiveness of the treatment of acute ACL tears with either initial surgical reconstruction or physical therapy in competitive athletes. Study Design: Economic and decision analysis; Level of evidence, 2. Methods: The incremental cost, incremental effectiveness, and incremental cost-effectiveness ratio (ICER) of ACL reconstruction compared with physical therapy were calculated from a cost-effectiveness analysis of ACL reconstruction compared with physical therapy for the initial management of acute ACL injuries in competitive athletes. The ACL reconstruction strategy and the physical therapy strategy were represented as Markov models. Costs and quality-adjusted life-years (QALYs) were evaluated over a 6-year time horizon and were analyzed from a societal perspective. Quality of life and probabilities of clinical outcomes were obtained from the peer-reviewed literature, and costs were compiled from a large academic hospital in the United States. One-way, 2-way, and probabilistic sensitivity analyses were used to assess the effect of uncertainty in variables on the ICER of ACL reconstruction. Results: The ICER of ACL reconstruction compared with physical therapy was

Association between orthopaedic in-training examination subsection scores and ABOS Part I examination performance.

22,702 per QALY gained. The ICER was most sensitive to the quality of life of returning to play or not returning to play, costs, and duration of follow-up but relatively insensitive to the rates and costs of complications, probabilities of return to play for both operative and nonoperative treatments, and discount rate. Conclusion: ACL reconstruction is a cost-effective strategy for competitive athletes with an ACL injury.

Nonoperative management versus reverse shoulder arthroplasty for treatment of 3- and 4-part proximal humeral fractures in older adults

Objectives The Orthopaedic In-Training Examination (OITE) is administered yearly to assess a resident’s progression, compare his or her performance with that of other residents, and evaluate the educational structure of a residency program. The American Board of Orthopaedic Surgery (ABOS) Part I examination is used to ensure competence in orthopedic knowledge and must be passed to achieve certification. Previous studies have correlated OITE and ABOS performance, but analysis between OITE subsection performance and ABOS Part I examination performance has not been reported. The purpose of this study was to evaluate the relation between individual OITE subsection performance and overall ABOS Part I performance. Methods Performance on the 12 subsections comprising the OITE from 1999 to 2009 was evaluated and compared with overall ABOS Part I examination performance. Spearman correlation coefficients (SCCs) were used to quantify the association between OITE subsection and overall ABOS percentile ranks. Results The OITE subsections of musculoskeletal trauma (SCC 0.29; P = 0.0002), hip and knee reconstruction (SCC 0.21; P = 0.0064), spine (SCC 0.16; P = 0.04), orthopedic science (SCC 0.17; P = 0.03), and orthopedic disease (SCC 0.18; P = 0.02) correlated with ABOS percentile ranks. Five of the top seven subsections by question volume on the OITE were found to correlate with ABOS performance. Conclusions OITE subsections with greater representation and breadth of subject matter had stronger performance correlations with ABOS Part I examination performance. These findings may allow residency training programs to better predict ABOS Part I performance of their residents by evaluating particular subsections on the OITE in addition to overall OITE performance.

Preoperative Ultrasonography Is Unreliable in Predicting Hamstring Tendon Graft Diameter for ACL Reconstruction

BACKGROUND The treatment of 3- and 4-part proximal humeral fractures in the older adult is controversial. No study has directly compared reverse shoulder arthroplasty (RSA) with nonoperative treatment for these fractures. The purpose of this study was to compare clinical and patient-reported outcomes between RSA and nonoperative treatment groups. METHODS A retrospective review was performed on all 3- and 4-part proximal humeral fractures treated with either RSA or nonoperative treatment with minimum 1-year follow-up. All patients in the nonoperative cohort were offered RSA but declined. Objective patient data were obtained from medical records. Patient-reported outcomes including visual analog scale score, Single Assessment Numeric Evaluation score, Penn Shoulder Score, American Shoulder and Elbow Surgeons score, resiliency score, and Veterans Rand-12 scores were obtained at follow-up. Statistical analysis was performed by use of the Student t test for continuous variables and χ2 analysis for nonparametric data. RESULTS We analyzed 19 nonoperative and 20 RSA patients with a mean follow-up period greater than 2 years (29 months in nonoperative group and 53 months in RSA group). There were no differences in range of motion between groups (forward elevation, 120° vs 119° [P = .87]; external rotation, 23° vs 31° [P = .06]). No differences between the nonoperative and RSA groups were noted for any patient-reported outcomes. Among patients receiving RSA, there was no difference in outcomes in those undergoing surgery less than 30 days after injury versus those receiving delayed RSA. CONCLUSIONS This study suggests that there are minimal benefits of RSA over nonoperative treatment for 3- and 4-part proximal humeral fractures in older adults.

Outcomes after arthroscopic fixation of tibial eminence fractures with bioabsorbable nails in skeletally immature patients.

Background: Hamstring autograft size <8 mm has been shown to be a predictor for failure after anterior cruciate ligament (ACL) reconstruction. The ability to predict graft size preoperatively is helpful in counseling patients about the possible need for graft augmentation. Purpose: To determine whether preoperative ultrasound (US) measurements of hamstring tendons can predict intraoperative graft diameter during ACL reconstruction. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: Twenty patients undergoing unilateral isolated ACL reconstruction were prospectively enrolled in the study (10 males, 10 females; mean ± SD age, 22.8 ± 6.6 years; height, 175.1 ± 7.1 cm; weight, 81.4 ± 14.2 kg; body mass index, 26.5 ± 4.1 kg/m2). Hamstrings were assessed by US, and double-looped semitendinosus-gracilis hamstring size was independently calculated with a freehand selection method on a nonmagnified US image by 2 orthopaedic surgeons. Intraoperative autograft size was determined with a standard graft-sizing tool. Intra- and interrater reliability was measured with intraclass correlation coefficients (ICCs) and standard error of the measure (SEM). A receiver operating characteristic curve was calculated to assess the ability of the US measurement to predict intraoperative measurements. Results: The mean autograft diameter by US was 8.9 ± 0.98 mm, while the mean intraoperative hamstring graft size was 8.1 ± 0.89 mm. There was excellent intrarater (ICC2,1 = 0.95, SEM = 0.32 mm) and interrater (ICC2,1 = 0.88, SEM = 0.55 mm) reliability for US measurements. Receiver operating characteristic analysis showed that US did not consistently quantify graft size. Graft size did not significantly correlate with height, weight, or body mass index in our sample (P > .05). Conclusion: These results suggest that preoperative US imaging of the hamstring tendons is unreliable in predicting intraoperative graft diameter.

Arthroscopic decompression at the suprascapular notch: a radiographic and anatomic roadmap.

The aim of this paper is to report the outcomes and any complications with arthroscopic bioabsorbable nail fixation of tibial eminence fractures in skeletally immature patients. We retrospectively reviewed all surgically treated tibial eminence fractures treated by a single surgeon and seven patients were identified with a minimum 2-year follow-up. Mean deficits of flexion and extension were minimal. Satisfactory Tegner levels, Lysholm knee scores, and International Knee Documentation Committee subjective scores were reported. Arthroscopic fixation of tibial eminence fractures with bioabsorbable nails yields satisfactory outcomes for this uncommon injury and obviates the need for future hardware removal.

Radial Head Dislocation

BACKGROUND Arthroscopic decompression of the suprascapular nerve (SSN) at the suprascapular notch is a technically demanding procedure. Additional preoperative and intraoperative information may assist surgeons. The purpose of this study was to (1) identify which imaging modality most accurately represents the anatomic distance to the notch and (2) quantify the mean intraoperative distances from routine arthroscopic portals to the notch. METHODS Ten matched pairs of fresh cadaveric shoulders were imaged by roentgenogram, computed tomography (CT), magnetic resonance imaging, and 3-dimensional (3D) CT, followed by arthroscopic SSN decompression at the notch and anatomic dissection. Measurements obtained included the distances from the anterolateral, posterior, and SSN portal sites to the notch in addition to the distance from the anterolateral acromion to the notch. Statistical analysis with Spearman correlation coefficients and Bland-Altman plots were used to determine the correlation and agreement between measurements. RESULTS The preoperative imaging modality with the highest correlation to anatomic distances from the anterolateral acromion to the notch was 3D CT (Rs = 0.90, P < .0001). The mean intraoperative distances to the notch from the anterolateral, posterior, and SSN arthroscopic portals were 89 mm, 88 mm, and 49 mm, respectively. The mean anatomic distance from the anterolateral acromion to the notch was 64 mm. CONCLUSIONS Preoperative imaging with 3D CT may assist surgeons in performing arthroscopic SSN decompression. Understanding of the mean distances from the portal sites to the suprascapular notch and being cautious of arthroscopic instruments placed beyond 9 cm from laterally based portals may result in safer intraoperative medial dissection.

Juvenile Idiopathic Arthritis

Radial head dislocations in children are most commonly due to one of two entities: congenital dislocation of the radial head or Monteggia fracture. Congenital dislocation is often asymptomatic until adolescence, and if symptomatic, it can be treated with radial head excision for pain relief. Monteggia fractures involve radial head dislocation in association with an ulna fracture or plastic deformation. Most can be treated with closed reduction maneuvers, but, when open or unstable, are treated surgically. Posterior interosseous nerve palsy is a potential complication (10%), but generally resolves spontaneously.