Faculty Bibliography

OBJECTIVE: A new closed reduction technique for anterior glenohumeral dislocations and tuberosity fracture dislocations is introduced. METHODS: Forty-one consecutive patients with an acute anterior glenohumeral dislocation or tuberosity fracture dislocation underwent closed reduction by an orthopaedic surgeon employing this new method. RESULTS: Closed reduction was successful in 88% of patients using the reduction maneuver. Associated fracture with glenohumeral dislocation did not influence the success rate of the reduction maneuver. An assistant was needed in 15% of cases. No complications related to the reduction maneuver were noted amongst the cohort. CONCLUSION: This novel reduction technique is safe demonstrating excellent success rates both for anterior shoulder dislocations and tuberosity fracture-dislocations.

PURPOSE: To determine when patients recover the ability to safely operate the brakes of an automobile after a right-knee anterior cruciate ligament reconstruction (ACLR). METHODS: A computerized driving simulator was used to determine braking ability after an isolated right-knee ACLR. Thirty healthy volunteers were tested at 1 visit to determine normal mean values, and 27 treatment subjects were tested at 1 week, 3 weeks, and 6 weeks after ACLR. Nine study subjects were treated with a patella tendon (BPTB) autograft, 9 were treated with a hamstring (HS) autograft, and 9 were treated with a tibialis anterior (TA) allograft. The driving simulator collected data on brake reaction time (BRT), brake travel time (BTT), and total brake time (TBT) at each visit. RESULTS: The control group generated a BRT of 725 milliseconds, BTT of 2.87 seconds, and TBT of 3.59 seconds. At week 1, all treatment patients had significant differences compared with controls for BRT, BTT, and TBT, except the BTT of the HS group. At week 3, all measures for the allograft group and the BRT for both autograft groups were no longer significantly different compared with controls, but significant differences were found for TBT in the HS and BPTB groups (P = .03, P = .01). At week 6, BRT, BTT, and TBT were no longer significantly different for either the HS group or BPTB group. CONCLUSIONS: Patients who underwent a right-knee ACLR with a TA allograft regained normal braking times by week 3 postoperatively. In contrast, those treated with a BPTB or HS autograft demonstrated significantly delayed braking times at 3 weeks but returned to normal braking ability by week 6. Those treated with an autograft had an earlier return of normalized BRT than BTT. LEVEL OF EVIDENCE: Level III, case-control series.

Osteochondral lesions of the talus are common injuries that affect a wide variety of active patients. The majority of these lesions are associated with ankle sprains and fractures though several nontraumatic etiologies have also been recognized. Patients normally present with a history of prior ankle injury and/or instability. In addition to standard ankle radiographs, magnetic resonance imaging and computed tomography are used to characterize the extent of the lesion and involvement of the subchondral bone. Symptomatic nondisplaced lesions can often be treated conservatively within the pediatric population though this treatment is less successful in adults. Bone marrow stimulation techniques such as microfracture have yielded favorable results for the treatment of small (<15 mm) lesions. Osteochondral autograft can be harvested most commonly from the ipsilateral knee and carries the benefit of repairing defects with native hyaline cartilage. Osteochondral allograft transplant is reserved for large cystic lesions that lack subchondral bone integrity. Cell-based repair techniques such as autologous chondrocyte implantation and matrix-associated chondrocyte implantation have been increasingly used in an attempt to repair the lesion with hyaline cartilage though these techniques require adequate subchondral bone. Biological agents such as platelet-rich plasma and bone marrow aspirate have been more recently studied as an adjunct to operative treatment but their use remains theoretical. The present article reviews the current concepts in the evaluation and management of osteochondral lesions of the talus, with a focus on the available surgical treatment options.

Osteoarthritis (OA) is a degenerative joint condition characterized by painful cartilage lesions that impair joint mobility. Current treatments such as lavage, microfracture, and osteochondral implantation fail to integrate newly formed tissue with host tissues, and establish a stable transition to subchondral bone. Similarly, tissue engineered grafts that facilitate cartilage and bone regeneration likewise are challenged by how to integrate the graft seamlessly with surrounding host cartilage and/or bone. This review centers on current approaches in promoting cartilage graft integration. It begins with an overview of articular cartilage structure and function, as well as degenerative changes to this relationship attributed to aging, disease, and trauma. A discussion of the current progress in integrative cartilage repair then follows, focusing on graft or scaffold design strategies targeting cartilage-cartilage and/or cartilage-bone integration. It is emphasized that integrative repair is required to ensure long term success of the cartilage graft and preserve the integrity of the newly engineered articular cartilage. Studies involving the use of enzymes, choice of cell source, biomaterial selection, growth factor incorporation, and stratified versus gradient scaffolds are therefore highlighted here. Moreover, models that accurately evaluate the ability of cartilage grafts to enhance tissue integrity and prevent ectopic calcification are also discussed. A summary and future directions section concludes the review.

OBJECTIVE: To describe the post-surgical imaging appearance and complications of high tibial osteotomy in patients with the iBalance implant system (iHTO; Arthrex, Naples, FL, USA). MATERIALS AND METHODS: Retrospective, institutional review board-approved, Health Insurance Portability and Accountability Act-compliant review of imaging after 24 iBalance procedures was performed with attention to: correction of varus malalignment, healing at the osteotomy site, resorption of the osteoinductive compound, and complications. RESULTS: Immediate correction of the varus deformity was present in all cases. Lobular radiolucency was present in all cases, more pronounced on the lateral knee radiograph, simulating infection or erosive disease. Four radiographic signs of healing were observed: blurring at the opposing osteotomy bony margins and at the osteoinductive compound and the adjacent bone interface, callus formation, and resorption of the osteoinductive compound. Complications were present in 33 % of cases, including fracture through the lateral tibial cortex (21 %), genu varum recurrence (8 %), painful exuberant bone formation (4 %), persistent pain, requiring total knee arthroplasty (4 %), and non-union (after >6 months' follow-up), with suspected infection (4 %). CONCLUSION: Radiologists should be aware of the normal radiographic appearance following iBalance high tibial osteotomy, which may be confused with infection. Radiologists should also be aware of potential post-operative complications and compare all post-operative radiographs with the immediate post-operative examination to detect collapse of the osteotomy site and recurrence of varus angulation.

PURPOSE: To investigate the biomechanical properties of the load shifting following opening-wedge distal femoral varus osteotomies (DFVOs) and determine the osteotomy correction needed to unload the lateral compartment. METHODS: Five human cadaveric knees were tested with a load of 500 N of axial compression. Medial and lateral tibiofemoral compartment contact area and pressure were assessed utilizing a modified F-scan pressure-sensitive sensor. The knees were tested in their baseline anatomic alignment, 10 degrees valgus malalignment and following corrective DFVOs of 5 degrees , 10 degrees and 15 degrees . The load shifting effect of the various DFVO correction angles was analysed using a one-way ANOVA to determine the correction angle necessary to unload the lateral compartment. RESULTS: Gradually shifting the loading vector medially with increasing DFVO angles resulted in a decrease in the mean contact area and mean contact pressures in the lateral compartment with progressive increases in the medial compartment. The largest reduction in lateral compartment pressure and contact area was seen with the 15 degrees osteotomy with a 25 % decrease in mean contact pressure and 20 % decrease in mean maximum contact pressure and mean contact area when compared to the 10 degrees valgus-malaligned knee. For the 10 degrees valgus knee, a 15 degrees correction resulted in near-normal contact pressures and areas compared with the knee in normal anatomic alignment. CONCLUSION: Progressive unloading of the lateral tibiofemoral compartment occurred with increasing DFVO correction angles. Clinically, when performing a DFVO for valgus malalignment, surgeons should consider overcorrecting the osteotomy by 5 degrees to restore near-normal contact pressures and contact areas in the lateral compartment rather than the traditional teaching of correcting to neutral alignment.

INTRODUCTION: Though outcomes following ACL reconstruction are largely positive, patients' post-operative recovery is highly variable, and is typically based off generalized timetables derived from population data. In an attempt to individualize prognostic estimates and establish how biomarker concentrations may change with injury, we sampled knee joint synovial fluid from patients with ACL tears with and without associated cartilage injuries and compared biomarker concentrations to samples obtained from the contralateral non-injured knee. Method: In an institutional review board approved study, 480 patients indicated for knee arthroscopy were consented and had samples drawn to form a synovial fluid database. If no injury history or symptoms were present in the contralateral knee, samples were drawn as well. For the current study, only patients that had confirmed ACL injury at the time of arthroscopy were included. Associated cartilage injury location, size and depth was documented. Synovial fluid samples were centrifuged, and the concentrations of 20 biomarkers were determined using a multiplex magnetic bead immunoassay. Concentrations were then compared between the three study groups (ACL tear with cartilage injury, ACL tears without cartilage injury, and healthy contralateral knees) using a Welch ANOVA test with pairwise comparisons. Results: The study included samples from 132 knees: 34 ACL tears without cartilage injury (mean age 34.0 years); 28 ACL tears with cartilage injury (mean age 36.3 years), and 72 contralateral knees (41.1 years). ANOVA testing demonstrated significant differences among groups for: MMP-3 (p>001); TIMP-1 (p=.001); TIMP-2 (p=.015); FGF-2 (p=.011); IL-6 (p=.001); and MlP-lb (p=001). Pairwise comparisons demonstrated no significant differences between ACL tears with, and without cartilage damage, but did show both types of ACL tears had significantly higher concentrations of MMP-3, TIMP-1, IL-6, and MlP-lb than contralaterals. ACL tears without cartilage damage had significantly lower concentrations of TIMP-2 and FGF-2 (13) than contralaterals (Table 1). Discussion: The course from surgery to symptomatic relief and functional improvement following ACL reconstruction is highly variable. Data from the current study demonstrated that cytokine concentrations are significantly different between ACL tears (+/- cartilage damage) and healthy knees. SIGNIFICANCE: These validated differences can help establish synovial fluid biomarker analysis as a method for injury stratification ultimately providing patient-specific prognostic data

Objectives: Introduction: Though outcomes following ACL reconstruction are largely positive, patients' postoperative recovery is highly variable, and is typically based off generalized timetables derived from population data. In an attempt to individualize prognostic estimates and establish how biomarker concentrations may change with injury, we sampled knee joint synovial fluid from patients with ACL tears with and without associated cartilage injuries and compared biomarker concentrations to samples obtained from the contralateral non-injured knee. Methods: 480 patients indicated for knee arthroscopy had samples drawn to form a synovial fluid database. If no injury history or symptoms were present in the contralateral knee, samples were drawn as well. For the current study, only patients that had confirmed ACL injury at the time of arthroscopy were included. Associated cartilage injury location, size and depth was documented. Synovial fluid samples were centrifuged, and the concentrations of 20 biomarkers were determined using a multiplex magnetic bead immunoassay. Concentrations were then compared between the three study groups (ACL tear with cartilage injury, ACL tears without cartilage injury, and healthy contralateral knees) using a Welch ANOVA test with pairwise comparisons. Results: The study included samples from 132 knees: 34 ACL tears without cartilage injury (mean age 34.0 years); 28 ACL tears with cartilage injury (mean age 36.3 years), and 72 contralateral knees (41.1 years). ANOVA testing demonstrated significant differences among groups for: MMP-3 (p>001); TIMP-1 (p=.001); TIMP-2 (p=.015); FGF-2 (p=.011); IL-6 (p=.001); and MIP-1b (p=.001). Pairwise comparisons demonstrated no significant differences between ACL tears with, and without cartilage damage, but did show both types of ACL tears had significantly higher concentrations of MMP-3, TIMP-1, IL-6, and MIP-1b than contralaterals. ACL tears without cartilage damage had significantly lower concentrations of TIMP-2 and FGF-2 (13) than contralaterals (Table 1). Conclusion: The course from surgery to symptomatic relief and functional improvement following ACL reconstruction is highly variable. Data from the current study demonstrated that cytokine concentrations are significantly different between ACL tears (+/- cartilage damage) and healthy knees. These validated differences can help establish synovial fluid biomarker analysis as a method for injury stratification ultimately providing patientspecific prognostic data. (Table Presented)

Background/Purpose: Persistent inflammation is a characteristic of several joint diseases, including OA. It is nowadays appreciated that this could be a result of a failure to (optimally) activate inflammation resolution pathways. Therefore, we investigated the presence of specialized pro-resolving lipid mediators (SPM) and their precursors as pathway markers of the resolution process in the joint of OA patients and controls. Methods: SF was obtained from knee OA (2 populations) and rheumatoid arthritis (RA) patients fulfilling the ACR criteria for OA and RA, respectively, and healthy controls. Lipid mediators (LMs) were determined by targeted lipidomics using liquid-chromatography mass spectrometry. Sixty different lipids including pro-inflammatory (e.g. prostaglandins, leukotrienes) and anti-inflammatory/pro-resolving LM (e.g. SPM), as well as their precursors can be detected with our technique. Results: SF from 24 OA and 12 RA patients were first studied. Thirty-seven lipids were detected in the soluble fraction of SF, including polyunsaturated fatty acids (PUFA) and their lipoxygenase (LOX) and cyclooxygenase (COX) pathway markers in both OA and RA patients. Among these, pro-inflammatory LM such as PGE2 and thromboxane B2, as well as the pathway markers of resolution and precursors of SPM, 17-HDHA and 18-HEPE, were detected. Except for the LOX products of arachidonic acid: 15-HETE, 6-trans-LTB4 and 20-OH- LTB4, which were lower in OA than in RA SF, all other lipid mediators and PUFA were comparable between OA and RA samples. Ratios of metabolites to their precursors indicated that both pro- (e.g. LTB4) and anti-inflammatory LOX products (e.g. 17- HDHA) are more efficiently generated in RA than in OA patients, while no differences were observed in COX products. Interestingly, the SPM resolvin D2 (RvD2) could also be detected, but only in the insoluble fraction (cells and undigested matrix), indicating that the resolution pathways are activated in OA. This expands our previous publication showing activation of resolution in RA patients. To assess the efficiency of activation of resolution in OA, we have performed targeted lipidomics on total SF in an additional study with 32 OA patients and 10 healthy controls. Confirming earlier data, most LMs were also detected in this study, including the pro-inflammatory PGE2, the SPM precursors 17-HDHA and 18-HEPE, and the SPM RvD2. Additionally, we detected 18S-resolvin E3 (18S-RvE3). Remarkably, both the absolute concentrations of the SPM RvD2 and 18S-RvE3, and the ratio to their precursors, 17-HDHA and 18-HEPE, were lower in OA compared to healthy SF, indicating less efficient generation of SPM in OA compared to healthy joints. In contrast, the proinflammatory lipid PGE2was higher in OA than in healthy SF, indicating that the lower activation of resolution is paired by a higher inflammatory load in OA compared with healthy individuals. Conclusion: By using a state-of-the-art technique, we show for the first time that resolution pathways are activated in OA patients. Importantly, resolution seems to be less efficiently activated than in healthy individuals, which could account for the persistent inflammation observed in OA and RA patients