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INTRODUCTION: Glenoid reconstruction is indicated for recurrent glenohumeral instability with significant glenoid bone deficiency. Coracoid autograft (Latarjet) and distal tibial osteochondral allograft (DTA) reconstructions have been used to successfully restore glenohumeral stability. Relative advantages and disadvantages associated with each reconstruction technique have been described. However, direct comparisons of functional glenohumeral biomechanics associated with Latarjet vs. DTA reconstruction are lacking. This study was designed to compare these 2 glenoid reconstruction techniques with respect to joint kinematics and cartilage pressure mapping using a robotic testing system. METHODS: In accordance with institutional review board policies, human cadaveric shoulders (n = 8) were cyclically tested in the neutral position and 90° of external rotation with 60° and 90° of abduction under a 45-N joint-compression load to measure clinically relevant translations, loads, and torques. Joint contact pressure maps were obtained under a 120-N joint-compression load using pressure mapping sensors. After confirming that a 25% anterior glenoid defect resulted in glenohumeral dislocation, testing was performed to compare 3 conditions: native intact glenoid, 25% anterior glenoid defect with Latarjet reconstruction, and 25% anterior glenoid defect with DTA reconstruction. Analyses of variance and t tests were used to analyze data with statistical significance set at P < .05. RESULTS: Significant differences in anterior translation, inferior drawer, anterior drawer, compression loads, horizontal abduction, negative elevation (adduction), and external rotation torques during cyclical testing in 90° of external rotation with 60° and/or 90° of abduction were noted when comparing the 2 different glenoid bone reconstruction techniques to native, intact shoulders. The only significant difference between Latarjet and DTA reconstructions for measured translations, loads, and torques was a significantly higher absolute maximum compressive load for Latarjet compared to DTA at 60° of abduction. CONCLUSION: Latarjet coracoid osseous autograft and distal tibial osteochondral allograft reconstructions of large (25%) glenoid bone defects prevent failure (dislocation) and are associated with significant glenohumeral kinematic differences that largely confer less translation, load, and torque on the joint in abduction when compared to the native state. These findings suggest that these 2 surgical techniques exhibit similar glenohumeral kinematics such that each provides adequate functional stability following anterior glenoid bone reconstruction. Joint compression load and articular contact pressure distribution may favor distal tibial osteochondral allograft reconstruction for treatment of large (25%) anterior glenoid bone defects associated with shoulder instability.

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OBJECTIVE: To create a treatment algorithm for focal grade 3 or 4 cartilage defects of the knee using both classic and novel cartilage restoration techniques. DESIGN: A comprehensive review of the literature was performed highlighting classic as well as novel cartilage restoration techniques supported by clinical and/or basic science research and currently being employed by orthopedic surgeons. RESULTS: There is a high level of evidence to support the treatment of small to medium size lesions (<2-4 cm2) without subchondral bone involvement with traditional techniques such as marrow stimulation, osteochondral autograft transplant (OAT), or osteochondral allograft transplant (OCA). Newer techniques such as autologous matrix-induced chondrogenesis and bone marrow aspirate concentrate implantation have also been shown to be effective in select studies. If subchondral bone loss is present OAT or OCA should be performed. For large lesions (>4 cm2), OCA or matrix autologous chondrocyte implantation (MACI) may be performed. OCA is preferred over MACI in the setting of subchondral bone involvement while cell-based modalities such as MACI or particulated juvenile allograft cartilage are preferred in the patellofemoral joint. CONCLUSIONS: Numerous techniques exist for the orthopedic surgeon treating focal cartilage defects of the knee. Treatment strategies should be based on lesion size, lesion location, subchondral bone involvement, and the level of evidence supporting each technique in the literature.

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BACKGROUND: The purpose of this study was to examine the impact of age on complication risk after anterior cruciate ligament reconstruction. METHODS: The TriNetX research database was retrospectively queried for patients undergoing primary arthroscopic ACL reconstruction. Univariate logistic regression was performed to evaluate the risk of complication by age group. RESULTS: A total of 21,449 patients were included in the study. Patients ≥61 years old demonstrated significantly higher rates of repeat reconstruction. Rates of postoperative opioid related disorders and surgical site infection varied by age. CONCLUSION: For patients undergoing ACL reconstruction, increasing age is associated with increased risk of developing opioid related disorders, and repeat reconstruction.

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OBJECTIVE: The addition of open subpectoral biceps tenodesis to arthroscopic shoulder surgery with interscalene block has been anecdotally observed to result in increased postoperative pain. This study aims to evaluate the impact of tenodesis on early postoperative pain and recovery. METHODS: A retrospective review of patients undergoing arthroscopic shoulder surgery with general anesthesia and interscalene block was conducted. RESULTS: Patients undergoing tenodesis experienced longer OR time, pain numeric rating scale (NRS), and consumed more morphine milligram equivalents (MME) in PACU. After controlling for confounding factors, tenodesis was significantly associated with increased opioid MME consumption in the PACU (ß = 1.045, p = .028) and last PACU pain NRS (ß = 0.541, p = .009). CONCLUSION: Overall, pain scores and narcotic consumption were low after surgery, making these differences potentially clinically insignificant. Further study is required to evaluate whether these trends are consistent among this population.

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This study compares bioabsorbable nail to metal screw fixation of shell osteochondral allograft (OCAs) for compression and shear strength. Cadaveric distal femurs (n = 5) yielding six 1.5 cm shell grafts (n = 30) were used. Three different fixation methods (2.0 and 2.4 mm headed screws, and copolymer absorbable nail) were compared for statistically significant differences (p < 0.05) in contact area, contact pressure, and shear load-to-failure. No significant differences in contact areas existed among groups (224 ± 33.5 mm2; 233.9 ± 20.8 mm2, 220.6 ± 22.7 mm2; p = 0.509 for 2.4, 2.0 mm screw, and nail, respectively). No significant differences in contact pressures existed (1.7 ± 0.6 MPa/mm2, 1.5 ± 0.8 MPa/mm2, 1.4 ± 0.9 MPa/mm2; p = 0.73 for 2.4, 2.0 mm screw, and nail, respectively). Load-to-failure for each was: 280.7 ± 48.4 N for 2.4 mm screws, 245.1 ± 70.6 N for 2.0 mm screws, and 215.2 ± 39.4 N for nails. There were no statistically significant differences in load-to-failure between 2.4 and 2.0 mm screws (p = 0.29) or between 2.0 mm screws and nails (p = 0.23); however, load-to-failure in shear was significantly higher for 2.4 mm screws compared with nails (p = 0.036). Fixation of shell OCAs using a copolymer headed nail provides initial graft-recipient compression similar to fixation using 2.0 and 2.4 mm headed screws. Nails failed in shear at significantly lower load than 2.4 mm screws but not 2.0 mm screws which have proven adequate for clinical healing. This study has clinical relevance, as a copolymer bioabsorbable headed nail (SmartNail) has graft-recipient compression and shear load-to-failure properties that suggest it is viable for shell OCA fixation.

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BACKGROUND: Articular cartilage defects of the knee can significantly impair function among young, high-demand patients. There are several techniques for chondral restoration, including osteochondral allograft transplantation (OCA), that may alleviate pain and re-create the native anatomy. However, clinical outcomes among athletic cohorts are limited. PURPOSE: To evaluate the efficacy and functional outcomes of OCA for medium to large osteochondral defects of the knee in physically active United States military servicemembers. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A military health care database was queried to identify all OCA procedures performed between January 2009 and March 2013. Inclusion criteria were army personnel with a minimum of 2 years' follow-up. Exclusion criteria included incomplete follow-up, inaccurate coding, and nonmilitary status. Variables of interest included sex, age, lesion location, grade and size of the lesion, body mass index, tobacco use, preoperative and postoperative visual analog scale (VAS) scores for pain, and presence of perioperative complications. Overall failure was defined as the inability to return to preoperative functional activities because of persistent knee complaints (clinical failure) or a revision cartilage procedure or arthroplasty (surgical failure). RESULTS: A total of 61 patients (52 male; mean age, 31.7 years) were identified, with a mean 46.2-month follow-up. The mean VAS pain score improved from 4.10 ± 2.17 preoperatively to 2.68 ± 2.73 postoperatively (P < .0009), and only 6 (9.8%) required a subsequent revision chondral procedure. Overall, 39 patients (63.9%) were able to return to a level of activity that allowed for the completion of military duties. Risk factors for clinical failure were preoperative body mass index, preoperative pain as measured on the VAS, and moderate to severe postoperative pain on the VAS. The risk factor for surgical failure was the presence of a complication. Risk factors for overall failure were the presence of a complication and moderate to severe postoperative pain on the VAS. CONCLUSION: OCA provided moderate success in retaining active-duty army servicemembers. Approximately two-thirds of patients undergoing OCA were able to return to their preinjury occupational activity, while approximately 57% of patients returned to prior levels without a subsequent revision chondral procedure or arthroplasty.

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PURPOSE: To determine whether the deep fibers of the iliotibial band (dITB) or the anterolateral ligament (ALL) provides more control of a simulated pivot shift and whether a minimally invasive anterolateral reconstruction (ALR) designed to functionally restore the ALL and dITB is mechanically equivalent to a modified Lemaire reconstruction (MLR). METHODS: Six matched pairs of cadaveric knees (N = 12) were subjected to a simulated pivot shift to evaluate anteroposterior translation; internal rotation; and valgus laxity at 0°, 30°, and 90° of flexion. The anterior cruciate ligament (ACL) was sectioned in all specimens, and retesting was performed. Within each pair, sequential sectioning of the ALL and dITB was performed, followed by testing; the contralateral knee was sectioned in reverse order. Knees underwent ACL reconstruction (ACLR) and repeat testing. Then, MLR (n = 6) or ALR (n = 6) was performed on matched pairs for final testing. RESULTS: Sectioning of the dITB versus ALL (after ACL sectioning) produced significantly more anterior translation at all flexion angles (P = .004, P = .012, and P = .011 for 0°, 30°, and 90°, respectively). The ACL-plus-dITB sectioned state had significantly more internal rotation at 0° versus ACL plus ALL (P = .03). ACLR plus ALR restored native anterior translation at all flexion angles. ACLR plus MLR restored anterior translation to native values only at 0° (P = .34). We found no statistically significant differences between ACLR plus ALR and ACLR plus MLR at any flexion angle for internal rotation or valgus laxity compared with the native state. CONCLUSIONS: ALR of the knee in conjunction with ACLR can return the knee to its native biomechanical state without causing overconstraint. The dITB plays a more critical role in controlling anterior translation and internal rotation at 0° than the ALL. The minimally invasive ALR was functionally equivalent to MLR for restoration of knee kinematics after ACLR. CLINICAL RELEVANCE: The dITB is more important than the ALL for control of the pivot shift. A minimally invasive extra-articular tendon allograft reconstruction was biomechanically equivalent to a modified Lemaire procedure for control of a simulated pivot shift.

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Little information is available regarding patient-based factors that may influence results following transforaminal lumbar interbody fusion (TLIF) in younger, high-demand individuals. A query of all TLIF procedures performed on active duty military personnel at our institution was conducted for the time period 2005 to 2008. Data was abstracted, including age, gender, military rank, preoperative diagnosis, complications, and ability to remain in the military. Favorable outcome was defined as the ability of the patient receiving TLIF to remain on active duty, without medical separation (Medical Evaluation Board [MEB]), at a minimum of 1 year postsurgery. Univariate analysis was conducted to identify potential risk factors for MEB. Factors with a univariate p value <0.2 were included in multivariate analysis and sensitivity testing to identify independent predictors of outcome. The cohort included 143 patients with an average age of 36.3 years and mean follow-up of 34.9 months. Younger age (odds ratio 0.93 per year increase in age; 95% confidence interval 0.87, 0.98) and Junior Enlisted rank (odds ratio 6.42; 95% confidence interval 2.20, 18.74) were found to increase the risk of MEB, and these relationships were maintained in the sensitivity analyses. These findings highlight the potential role of activity level and sociodemographic status in outcomes after TLIF in a military population.

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Scapulothoracic arthroscopy is an established method for evaluating the articulation between the thoracic cage and the scapula. The "chicken-wing" position is often used to enhance visualization of the scapulothoracic space. There are situations in which the chicken-wing position is not feasible or practical, such as in simultaneous arthroscopy of both joints. In this article, we describe a new technique that aids in arthroscopy of the scapulothoracic joint, particularly when the chicken-wing position is unavailable.

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BACKGROUND: A prospective, longitudinal analysis of musculoskeletal combat injuries sustained by a large combat-deployed maneuver unit has not previously been performed. METHODS: A detailed description of the musculoskeletal combat casualty care statistics, distribution of wounds, and mechanisms of injury incurred by a US Army Brigade Combat Team during "The Surge" phase of Operation Iraqi Freedom was performed using a centralized casualty database and an electronic medical record system. RESULTS: Among the 4,122 soldiers deployed, there were 242 musculoskeletal combat wounds in 176 combat casualties. The musculoskeletal combat casualty rate for the Brigade Combat Team was 34.2 per 1,000 soldier combat-years. Spine, pelvis, and long bone fractures comprised 55.9% (33 of 59) of the total fractures sustained in combat. Explosions accounted for 80.7% (142 of 176) of all musculoskeletal combat casualties. Musculoskeletal combat casualty wound incidence rates per 1,000 combat-years were as follows: major amputation, 2.1; minor amputation, 0.6; open fracture, 5.0; closed fracture, 6.4; and soft-tissue/neurovascular injury, 32.8. Among musculoskeletal combat casualties, the likelihood of a gunshot wound causing an open fracture was significantly greater (45.8% [11 of 24]) when compared with explosions (10.6% [15 of 142]) (p = 0.0006). Long bone amputations were more often caused by explosive mechanisms than gunshot wounds. CONCLUSIONS: A large burden of complex orthopedic injuries has resulted from the combat experience in Operation Iraqi Freedom. This is because of increased enemy reliance on explosive devices, the use of individual and vehicular body armor, and improved survivability of combat-injured soldiers.

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Fibroblast growth factor-1 (FGF-1) is a potent angiogenic factor; its structure lacks a signal peptide for secretion. We previously reported that the overexpression of a secreted version of FGF-1 (sp-FGF-1) in microvascular endothelial cells (ECs) enhances cell migration [Partridge et al. J Cell Biochem 2000; 78(3): 487]. In the current study, we have examined the angiogenic effects of sp-FGF-1 in chicken chorioallantoic membranes (CAMs). Two methods of examining the effects of sp-FGF-1 in CAMs were used: cell-mediated transfection via bovine ECs and direct gene transfection. In the cell-mediated gene transfection, those eggs that were implanted with a gelatin sponge seeded with ECs stably transfected to over-express sp-FGF-1 protein showed a significant increase in angiogenesis inside the sponge when compared to eggs treated with vector control-transfected ECs. In the direct gene transfer, eggs received sp-FGF-1 showed a significant increase in vascularization when compared to eggs received vector alone plasmids. These CAM models are useful both for studying molecular mechanisms of angiogenesis and for developing better gene therapy strategies.

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