Removing the barriers to prehospital blood: a roadmap to success.

ABSTRACT: This review describes the necessity, evolution, and current state of prehospital blood programs in the United States. Less than 1% of 9-1-1 Ground Emergency Medical Service agencies have been able to successfully implement prehospital blood transfusions as part of a resuscitation strategy for patients in hemorrhagic shock despite estimates that annually between 54,000 and 900,000 patients may benefit from its use. The use of prehospital blood transfusions as a tool for managing hemorrhagic shock has barriers to overcome to ensure it becomes widely available to patients throughout the United States. Barriers include 1) current state Emergency Medical Services clinicians' scope of practice limitations, 2) program costs and reimbursement of blood products, 3) no centralized data collection process for prehospital hemorrhagic shock and patient outcomes, 4) collaboration between prehospital agencies, blood suppliers, and hospital clinicians and transfusion service activities. The following paper identifies barriers and a proposed roadmap to reduce death due to prehospital hemorrhage.

Scalable manufacture of therapeutic mesenchymal stromal cell products on customizable microcarriers in vertical wheel bioreactors that improve direct visualization, product harvest, and cost.

BACKGROUND AIMS: Human mesenchymal stromal cells (hMSCs) and their secreted products show great promise for treatment of musculoskeletal injury and inflammatory or immune diseases. However, the path to clinical utilization is hampered by donor-tissue variation and the inability to manufacture clinically relevant yields of cells or their products in a cost-effective manner. Previously we described a method to produce chemically and mechanically customizable gelatin methacryloyl (GelMA) microcarriers for culture of hMSCs. Herein, we demonstrate scalable GelMA microcarrier-mediated expansion of induced pluripotent stem cell (iPSC)-derived hMSCs (ihMSCs) in 500 mL and 3L vertical wheel bioreactors, offering several advantages over conventional microcarrier and monolayer-based expansion strategies. METHODS: Human mesenchymal stromal cells derived from induced pluripotent cells were cultured on custom-made spherical gelatin methacryloyl microcarriers in single-use vertical wheel bioreactors (PBS Biotech). Cell-laden microcarriers were visualized using confocal microscopy and elastic light scattering methodologies. Cells were assayed for viability and differentiation potential in vitro by standard methods. Osteogenic cell matrix derived from cells was tested in vitro for osteogenic healing using a rodent calvarial defect assay. Immune modulation was assayed with an in vivo peritonitis model using Zymozan A. RESULTS: The optical properties of GelMA microcarriers permit noninvasive visualization of cells with elastic light scattering modalities, and harvest of product is streamlined by microcarrier digestion. At volumes above 500 mL, the process is significantly more cost-effective than monolayer culture. Osteogenic cell matrix derived from ihMSCs expanded on GelMA microcarriers exhibited enhanced in vivo bone regenerative capacity when compared to bone morphogenic protein 2, and the ihMSCs exhibited superior immunosuppressive properties in vivo when compared to monolayer-generated ihMSCs. CONCLUSIONS: These results indicate that the cell expansion strategy described here represents a superior approach for efficient generation, monitoring and harvest of therapeutic MSCs and their products.

TWIST1 and TSG6 are coordinately regulated and function as potency biomarkers in human MSCs.

Mesenchymal stem/stromal cells (MSCs) have been evaluated in >1500 clinical trials, but outcomes remain suboptimal because of knowledge gaps in quality attributes that confer potency. We show that TWIST1 directly represses TSG6 expression that TWIST1 and TSG6 are inversely correlated across bone marrow-derived MSC (BM-MSC) donor cohorts and predict interdonor differences in their proangiogenic, anti-inflammatory, and immune suppressive activity in vitro and in sterile inflammation and autoimmune type 1 diabetes preclinical models. Transcript profiling of TWIST1HiTSG6Low versus TWISTLowTSG6Hi BM-MSCs revealed previously unidentified roles for TWIST1/TSG6 in regulating cellular oxidative stress and TGF-ß2 in modulating TSG6 expression and anti-inflammatory activity. TWIST1 and TSG6 levels also correlate to donor stature and predict differences in iPSC-derived MSC quality attributes. These results validate TWIST1 and TSG6 as biomarkers that predict interdonor differences in potency across laboratories and assay platforms, thereby providing a means to manufacture MSC products tailored to specific diseases.

Morpholino-driven blockade of Dkk-1 in osteosarcoma inhibits bone damage and tumour expansion by multiple mechanisms.

BACKGROUND: Osteosarcoma (OS) is the most common primary bone malignancy. Chemotherapy plays an essential role in OS treatment, potentially doubling 5-year event-free survival if tumour necrosis can be stimulated. The canonical Wnt inhibitor Dickkopf-1 (Dkk-1) enhances OS survival in part through upregulation of aldehyde-dehydrogenase-1A1 which neutralises reactive oxygen species originating from nutritional stress and chemotherapeutic challenge. METHODS: A vivo morpholino (DkkMo) was employed to block the expression of Dkk-1 in OS cells. Cell mitosis, gene expression and bone destruction were measured in vitro and in vivo in the presence and absence of doxorubicin (DRB). RESULTS: DkkMo reduced the expression of Dkk-1 and Aldh1a1, reduced expansion of OS tumours, preserved bone volume and architecture and stimulated tumour necrosis. This was observed in the presence or absence of DRB. CONCLUSION: These results indicate that administration of DkkMo with or without chemotherapeutics can substantially improve OS outcome with respect to tumour expansion and osteolytic corruption of bone in experimental OS model.

A scalable system for generation of mesenchymal stem cells derived from induced pluripotent cells employing bioreactors and degradable microcarriers.

Human mesenchymal stem cells (hMSCs) are effective in treating disorders resulting from an inflammatory or heightened immune response. The hMSCs derived from induced pluripotent stem cells (ihMSCs) share the characteristics of tissue derived hMSCs but lack challenges associated with limited tissue sources and donor variation. To meet the expected future demand for ihMSCs, there is a need to develop scalable methods for their production at clinical yields while retaining immunomodulatory efficacy. Herein, we describe a platform for the scalable expansion and rapid harvest of ihMSCs with robust immunomodulatory activity using degradable gelatin methacryloyl (GelMA) microcarriers. GelMA microcarriers were rapidly and reproducibly fabricated using a custom microfluidic step emulsification device at relatively low cost. Using vertical wheel bioreactors, 8.8 to 16.3-fold expansion of ihMSCs was achieved over 8 days. Complete recovery by 5-minute digestion of the microcarriers with standard cell dissociation reagents resulted in >95% viability. The ihMSCs matched or exceeded immunomodulatory potential in vitro when compared with ihMSCs expanded on monolayers. This is the first description of a robust, scalable, and cost-effective method for generation of immunomodulatory ihMSCs, representing a significant contribution to their translational potential.

Automated mesenchymal stem cell segmentation and machine learning-based phenotype classification using morphometric and textural analysis.

Purpose: Mesenchymal stem cells (MSCs) have demonstrated clinically relevant therapeutic effects for treatment of trauma and chronic diseases. The proliferative potential, immunomodulatory characteristics, and multipotentiality of MSCs in monolayer culture is reflected by their morphological phenotype. Standard techniques to evaluate culture viability are subjective, destructive, or time-consuming. We present an image analysis approach to objectively determine morphological phenotype of MSCs for prediction of culture efficacy. Approach: The algorithm was trained using phase-contrast micrographs acquired during the early and mid-logarithmic stages of MSC expansion. Cell regions are localized using edge detection, thresholding, and morphological operations, followed by cell marker identification using H-minima transform within each region to differentiate individual cells from cell clusters. Clusters are segmented using marker-controlled watershed to obtain single cells. Morphometric and textural features are extracted to classify cells based on phenotype using machine learning. Results: Algorithm performance was validated using an independent test dataset of 186 MSCs in 36 culture images. Results show 88% sensitivity and 86% precision for overall cell detection and a mean Sorensen-Dice coefficient of 0.849 ± 0.106 for segmentation per image. The algorithm exhibited an area under the curve of 0.816 ( CI 95 = 0.769 to 0.886) and 0.787 ( CI 95 = 0.716 to 0.851) for classifying MSCs according to their phenotype at early and mid-logarithmic expansion, respectively. Conclusions: The proposed method shows potential to segment and classify low and moderately dense MSCs based on phenotype with high accuracy and robustness. It enables quantifiable and consistent morphology-based quality assessment for various culture protocols to facilitate cytotherapy development.

Characterization of a pluripotent stem cell-derived matrix with powerful osteoregenerative capabilities.

Approximately 10% of fractures will not heal without intervention. Current treatments can be marginally effective, costly, and some have adverse effects. A safe and manufacturable mimic of anabolic bone is the primary goal of bone engineering, but achieving this is challenging. Mesenchymal stem cells (MSCs), are excellent candidates for engineering bone, but lack reproducibility due to donor source and culture methodology. The need for a bioactive attachment substrate also hinders progress. Herein, we describe a highly osteogenic MSC line generated from induced pluripotent stem cells that generates high yields of an osteogenic cell-matrix (ihOCM) in vitro. In mice, the intrinsic osteogenic activity of ihOCM surpasses bone morphogenic protein 2 (BMP2) driving healing of calvarial defects in 4 weeks by a mechanism mediated in part by collagen VI and XII. We propose that ihOCM may represent an effective replacement for autograft and BMP products used commonly in bone tissue engineering.

Patient-Reported Outcomes After Structural Autograft for Large or Cystic Talar Dome Osteochondral Lesions.

BACKGROUND: While smaller talar dome osteochondral lesions (OCLs) are successfully treated with bone marrow stimulation techniques, the optimal treatment for large or cystic OCLs remains controversial. This study tested the hypothesis that transferring structural autograft bone from the distal tibia to the talus for large or cystic OCLs improves pain and function. METHODS: Thirty-two patients with large or cystic OCLs underwent structural bone grafting from the ipsilateral distal tibia to the talar dome. Patients were assessed with subjective patient-centered tools and objective clinical outcomes. Average age was 48.6 ± 14.9 years, and average follow-up was 19.5 ± 13.3 months. Average lesion area was 86.2 ± 23.5 mm2, and average depth was 8.4 ± 3.0mm. RESULTS: At final follow-up, improvement compared to preoperative scores was seen in American Orthopaedic Foot & Ankle Society (65.4 ± 21.2 to 86.9 ± 15.0, P < .05), Foot Function Index (48.9 ± 20.8 to 21.1 ± 18.9, P < .05), visual analog scale for pain (4.7 ± 3.0 to 1.4 ± 1.5, P < .05), and Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (40.4 ± 5.4 to 45.5 ± 7.4, P < .05) scores. There was no improvement in PROMIS pain interference (54.7 ± 18.1 to 52.4 ± 7.3, P > .05). Satisfaction with surgery was 8.4 ± 1.3/10, and 96% of patients would have the procedure again. Ninety-four percent of patients returned to work and/or play. One patient had a deep vein thrombosis 6 weeks postoperatively, and 1 patient underwent ankle fusion at 18 months postoperatively. CONCLUSION: This study demonstrates that structural bone graft harvested from the distal tibia transferred to the talus was a safe and effective treatment for large and cystic OCLs. Outcomes compare favorably to other described techniques for treatment of these injuries. LEVEL OF EVIDENCE: Level IV, case series.

Natural History of Avascular Necrosis in the Talus: When to Operate.

Avascular necrosis (AVN) of the talus bone is a progressive and debilitating consequence of trauma or exposure to a variety of risk factors. The Ficat classification describes current understanding of the natural history of AVN, including preclinical, preradiographic, precollapse, postcollapse, and arthritic stages. The size and location of the avascular region likely determines risk of progression; however, symptoms do not correlate with stage. Patients may be minimally symptomatic despite diffuse involvement for long periods. Joint-sparing strategies have shown promise but do not universally prevent progression of the disease. When bone structure fails, joint-sacrificing strategies may be required.

Scandinavian Total Ankle Replacement: 15-Year Follow-up.

BACKGROUND: Over the past decade, total ankle arthroplasty (TAA) has become a mainstay in the treatment of end-stage ankle arthritis. Currently in its fourth generation, the Scandanavian Total Ankle Replacement (STAR) is the only 3-piece mobile bearing ankle prosthesis available in the United States. Our current study reports implant survivorship at 15 years and patient outcomes for a subset of these survivors available for study. METHODS: Eighty-four TAAs were performed between 1998 and 2000. Metal component survivorship at 15 years was calculated with a Kaplan-Meier curve. Twenty-four (29%) of 84 patients were available for participation with a minimum 15-year follow-up. Any radiographic changes were documented. All additional procedures and complications were recorded. Clinical findings, self-reported performance and pain evaluations, and AOFAS ankle/hindfoot scores were noted. RESULTS: Metal implant survival was 73% at 15 years. Of the 24 patients available for clinical evaluation, 18 of 24 patients (70.7%) had no change in prosthetic alignment from the immediate postoperative radiograph. Only 1 subtalar fusion was required for symptomatic adjacent joint arthritis. Three patients sustained a broken polyethylene component. AOFAS scores improved from an average of 39.6 points preoperatively, to an average of 71.6. More than half (52.4%) of patients with retained implants required an additional surgical procedure; 3 required 2 additional procedures. The average time to subsequent procedure was 10.2 years. CONCLUSION: Our small cohort demonstrated STAR ankles with retention at 9 years were highly likely to survive to 15 years, and patients continued to have significant improvement in pain relief and minimal decrease in function. At 15 years from TAA, metal survivorship was 73%. As with all ankle replacements, supplementary procedures were common. LEVEL OF EVIDENCE: Level IV, case series.

Implementation of Patient-Reported Outcomes Measurement Information System Data Collection in a Private Orthopedic Surgery Practice.

BACKGROUND: The authors describe a method of collecting patient-reported outcomes (PROs) using computerized adaptive tests (CATs) in a high-volume orthopedic surgery practice with limited resources and no research coordinator. METHODS: Patient-Reported Outcomes Measurement Information System CATs were collected prospectively for all clinic patients using a tablet and recorded in the electronic medical record. Scores were compared with validated national norms using single-variable t tests. Linear regression was used to assess age effects. Preoperative and postoperative pain scales were compared using paired t tests. RESULTS: In total, 4,524 CATs were administered during 10,719 visits (42%), reaching 70% as more tablets were introduced. Completing the CATs required 157 seconds. Older patients took more time than younger ones ( P < .05). Compared with normalized t scores of 50 ± 10 for the US population, pain intensity was 48.0 (95% confidence interval [CI], 47.8-48.2), pain interference 58.9 (95% CI, 58.6-59.1), physical function 40.1 (95% CI, 39.9-40.3), global physical health 43.4 (95% CI, 41.9-44.9), and global mental health 41.1 (95% CI, 40.89-41.4) ( P < .05 for all). Age had a small effect on all domains ( P < .05). Approximately 20 patients would be required to demonstrate a 15% change for a 2-tailed, paired study with α = 0.05 and 80% power. After surgery, pain intensity improved from 51.9 ± 8.2 to 44.1 ± 8.5, pain interference improved from 62.5 ± 6.9 to 55.7 ± 8.4, and physical function improved from 37.3 ± 8.9 to 41.5 ± 7.9 ( P < .05 for all). CONCLUSIONS: Using tablets to administer CATs and entering the data in the electronic medical record for later retrieval was an effective technique to collect PROs. An adequate number of tablets are needed for acceptable completion rates. Modest sample size requirements for comparative studies highlight the potential of these tools and techniques. LEVEL OF EVIDENCE: Level II, Prospective Comparative Study.

Association of Short-term Complications With Procedures Through Separate Incisions During Total Ankle Replacement.

BACKGROUND: Surgeons disagree about the safety of adding adjuvant procedures requiring separate incisions during total ankle replacement (TAR). This study tested the hypothesis that complication rates for patients in the first year after TAR would be greater when combined with procedures through separate incisions. METHODS: A retrospective review was performed on a consecutive series of 124 patients who underwent total ankle replacement between 2007 and 2013. Demographics, case-specific data, and postoperative complications over the first year were collected. A chi-square analysis was performed to compare differences in complication rates among patients with and without additional procedures requiring a separate incision. The average patient age was 67±10 years. Fourteen patients (11%) were diabetic and 2 patients (2%) were current smokers. Eighty-seven (70%) had prior trauma leading to arthritis. Ninety-seven (78%) cases used the Scandinavian Total Ankle Replacement (STAR), 16 (13%) Salto Talaris, and 11 (9%) In Bone implants. Ten (8%) cases were revisions. Excluding percutaneous Achilles lengthening, 35 of 124 patients (28%) had a total of 54 adjuvant procedures requiring a separate incision during TAR. These included 9 (7%) calcaneal osteotomies, 8 (6%) medial malleolar fixation, 6 (5%) subtalar fusions, 5 (4%) lateral ligament repair, 4 (3%) open Achilles lengthening, 4 (3%) removal of hardware, 2 (2%) first metatarsal osteotomy, and 8 other procedures. RESULTS: Overall, 32 (26%) of the 124 patients had a complication, including 15 (12%) delayed wound healing, 6 (5%) malleolar fracture, and 11 other complications. At 1 year, 24 (27%) of 89 patients without additional incisions and 8 (23%) of 35 patients with additional incisions, excluding percutaneous Achilles lengthening, had any complication (P = .64). DISCUSSION: This study did not demonstrate an association between additional procedures requiring a separate incision during TAR and early complications. Overall complication rates were similar to previously reported series of TAR. This study suggests that surgeons can add adjuvant procedures during TAR to improve alignment, stability, or treat adjacent segment arthritis without affecting short-term complication rates. The necessity or utility of these adjuvant procedures requires further study. LEVEL OF EVIDENCE: Level III, comparative series.

Safe zone for placement of talar screws when fusing the ankle with an anterior plating system.

BACKGROUND: Ankle fusions fixed with anterior plates use fluoroscopic guidance to direct screws toward the subtalar joint. Special imaging views that visualize the subtalar joint are difficult to use and can be unreliable. This study evaluated whether a single lateral ankle view would provide adequate information to judge whether a screw penetrated the subtalar joint and identified strategies that would improve this technique. METHODS: In 5 cadaveric ankles fixed with anterior plates, talar screws were placed up to the subtalar joint without penetration using lateral fluoroscopy to guide screw length. After dissection, the true distance from the screw tip to subchondral surface was measured. In addition, 4 readers measured the perceived distance from screw tip to subchondral surface using direct lateral, 10 degrees cephalad tilt lateral, and 10 degrees caudal tilt lateral fluoroscopic images on 2 separate occasions. RESULTS: Nineteen (63%) of 30 screws penetrated the subchondral bone, and screw length determined using fluoroscopy was significantly longer than screw length measured directly (29.4 ± 5.5 mm vs 27.3 ± 8.5 mm, P = .014). Measurement of screw tip to bone distance demonstrated a high level of within-reader (kappa = .871, P < .001) and between-reader agreement (kappa = .807, P < .001), but poor specificity of determining screw penetration (0.50, χ(2) = 22.1, P < .001) and poor correlation between radiographically measured and actual distances between screw tip and bone margin (r = .35, P < .001). Tilting the c-arm 10 degrees cephalad and directing screws toward the posterior facet improved the ability to detect screw penetration and directing screws toward the middle facet diminished it (P < .05). A safe zone of screw placement was defined by region. CONCLUSION: Use of a lateral fluoroscopic image to guide talar screw placement may lead to an unacceptably high rate of subtalar joint penetration. CLINICAL RELEVANCE: Understanding the limitations of lateral fluoroscopy when using anterior ankle fusion plates may minimize screw penetration into the subtalar joint and diminish development of subtalar arthropathy.

The "not so simple" ankle fracture: avoiding problems and pitfalls to improve patient outcomes.

Ankle fractures are among the most common injuries managed by orthopaedic surgeons. Many ankle fractures are simple, with straightforward management leading to successful outcomes. Some fractures, however, are challenging, and debate arises regarding the best treatment to achieve an optimal outcome. Some patients have medical comorbidities that increase the risk for complications or may require modifications to standard surgical techniques and fixation methods. Several recent investigations have highlighted the pitfalls in accurately reducing syndesmotic injuries. Controversy remains regarding the number and diameter of screws, the duration of weight-bearing limitations, and the need or timing of screw removal. Open reduction may allow more accurate reduction than standard closed methods. Direct fixation of associated posterior malleolus fractures may provide improved syndesmotic stability. Posterior malleolus fractures vary in size and can be classified based on the orientation of the fracture line. As the size of the posterior malleolus fracture fragment increases, the load pattern in the ankle is altered. Direct or indirect reduction and surgical fixation may be required to prevent posterior talar subluxation and restore articular congruency. The supination-adduction fracture pattern is also important to recognize. Articular depression of the medial tibial plafond may require reduction and bone grafting. Optimal fixation requires directing screws parallel to the ankle joint or using a buttress plate. Identifying ankle fractures that may present additional treatment challenges is essential to achieving a successful outcome. A careful review of radiographs and CT scans, a thorough patient assessment, and detailed preoperative planning are needed to improve patient outcomes.

Osteoarthritis of the ankle: the role of arthroplasty.

Total ankle arthroplasty was developed to reduce pain and retain motion of the ankle joint in patients with osteoarthritis. The ankle joint has unique, complex anatomic and biomechanical characteristics that must be considered in a successful total ankle arthroplasty prosthesis. Initial designs from the 1960s to the 1970s had many failures. Current designs use two or three components, and recent reports on total ankle arthroplasty show consistent good to excellent intermediate clinical results, with up to 90% decreased pain and high patient satisfaction. The follow-up time of these studies is limited, however, and long-term studies with 10- to 15-year follow-ups are needed. Also, a wide variety of complications has been reported, including osteomyelitis and osteolysis. To limit the number of complications and improve clinical outcome of total ankle arthroplasty, careful patient selection and surgeon experience are important.

Fixation of osteoporotic distal fibula fractures: A biomechanical comparison of locking versus conventional plates.

The increased use of locking plates to treat difficult fracture scenarios has been advocated in patients that have reduced bone mineral density. One of these difficult fracture patterns, fixation of the distal fragment of a distal fibula fracture, may depend on unicortical and cancellous bony purchase. This study investigated the construct stiffness afforded by using locking and conventional plating schema in a cadaveric model. Overall, the data indicate that a locking plate construct with two distal unicortical screws was mechanically equivalent to standard plating with 3 distal screws. In addition, fixation with the standard plates was dependent on bone mineral density (BMD) whereas the locking plate fixation was independent of BMD. The clinical implication of this study is that locking plates may be advantageous in patients with the most severe osteoporosis.

Subtalar joint arthrodesis using a single lag screw.

BACKGROUND: This study tested the hypotheses that fusing the subtalar joint with a single lag screw from the posteroinferior calcaneus to the anterior talar neck is an effective technique and that factors affecting the time to fusion can be identified. METHODS: Between October, 1995, and July, 2002, the senior author (RAM) performed 101 isolated subtalar arthrodeses using a technique of single lag-screw fixation from posteroinferior to anterosuperior across the posterior facet of the subtalar joint combined with the application of an autograft taken from the floor of the sinus tarsi and anterior process. The average patient age was 52 (range 17 to 82) years. There were 52 women (53 arthrodeses) and 48 men (48 arthrodeses). Eight of 101 (8%) arthrodeses were revisions. The indications included posttraumatic arthritis (45), posterior tibial tendon dysfunction (18), failed prior ankle joint fusion (14), idiopathic disorders (12), hindfoot coalition (7), rheumatoid arthritis (3), and Charcot-Marie-Tooth disease (2). Fifteen of 101 patients (15%) smoked an average of 0.9 +/- 0.5 pack of cigarettes per day. RESULTS: Two of 101 joints did not fuse, resulting in an overall fusion rate of 98%. The average time to fusion was 12.3 +/- 3.4 weeks. The presence of a prior ankle fusion significantly prolonged the time to fusion of the subtalar joint (11.9 +/- 2.3 vs. 14.9 +/- 7.0, p = .003). Other factors, including smoking, revision surgery, patient age, and patient sex, did not affect time to fusion. The fixation screw was removed in 13 of 101 (13%) joints at an average of 8.8 +/- 0.5 months. CONCLUSIONS: Using a single 7.0-mm lag screw across the posterior facet of the subtalar joint results in fusion of the subtalar joint in 98% of patients. A prior ankle arthrodesis delays the time to fusion of the subtalar joint by 3 weeks. This is a simple and reliable technique for achieving fusion of the subtalar joint.

Ankle arthroplasty with preoperative coronal plane deformity: short-term results.

The treatment of coronal plane deformity during total ankle arthroplasty is understood poorly. This study tests the hypotheses that preoperative coronal plane malalignment and incongruence of the ankle can be corrected and maintained for 2 years with total ankle replacement, and that factors can be identified that place ankles at risk of having progressive edge-loading develop. Of 86 consecutive patients who had total ankle replacement, 35 had preoperative coronal plane alignment > or =10 degrees. Lateral ligament reconstruction was done in seven patients and superficial deltoid release was done in four patients at the time of ankle replacement. Ankles with talar and tibial deformities improved talar and tibial alignment toward a neutral weightbearing axis postoperatively. Ankles with only a talar deformity improved the talar alignment toward a neutral weightbearing axis postoperatively. No changes in alignment were shown during the subsequent 2 years. Postoperative ankle articulations were congruent. Patients with preoperative incongruent joints are 10 times more likely to have progressive edge-loading develop than patients with congruent joints. Surgeons must be attentive to coronal plane alignment during and after ankle replacement. Longer followup is needed to assess the longevity of the correction and the impact of minor malalignment on implant wear.

Perioperative complication rate of total ankle replacement is reduced by surgeon experience.

BACKGROUND: Recent studies suggest the perioperative complication rate of total ankle arthroplasty decreases as a surgeon becomes familiar with the procedure. This study tests the hypothesis that the number of perioperative adverse events will decrease as surgeon experience with total ankle replacement increases. METHODS: Ten surgeons completed retrospective chart and radiographic reviews of their first 10 cases as well as 10 subsequent cases of the Scandinavian Total Ankle Replacement (STAR). Not all surgeons completed 10 cases within the allotted time periods, and two patients were excluded for less than 3-month follow-up, resulting in 187 cases for review. The surgeons performed an average of 12.8 (range, 0-61) STARs between these two time periods. Cases were divided into Early Group if they were among the first five STARs a surgeon performed and Late Group if they were after the first five. RESULTS: The average patient age was 60.4 +/- 12.8 years. The etiology of arthrosis included 96 (51%) of 187 posttraumatic, 49 (26%) idiopathic, and 33 (18%) rheumatoid. Patients in Early Group had a 3.1 times greater chance of having a perioperative adverse event (95% CI 1.6-6.1, p <.001), and a 3.2 times greater chance of having a perioperative wound problem (95% CI 1.5-6.8, p =.002) than patients in Late Group. Patients in Early Group took 1 week longer to heal their wounds than patients in Late Group (4.5 vs. 3.5 weeks, p =.046). CONCLUSIONS: This study shows a decrease in the perioperative adverse event rate commensurate with surgeon experience with STAR. In contrast to other reports, this study was unable to show a decrease in the number of perioperative fractures with increasing surgeon experience. This information is important for planning how best to train surgeons new to total ankle replacement and for patient counseling regarding the potential risks of the procedure.