The arthroscopic treatment of anterior shoulder instability with glenoid bone loss shows similar clinical results after Latarjet procedure and iliac crest autograft transfer.

PURPOSE: Recurrent anterior shoulder instability caused by critical bone loss of the glenoid is a challenging condition for shoulder surgeons. The purpose of this prospective multicenter trial was to compare the arthroscopic transfer of the coracoid process (Latarjet procedure) with the arthroscopic reconstruction of the glenoid using iliac crest autografts. METHODS: A prospective multi-center trial was performed in nine orthopaedic centres in Austria, Germany and Switzerland between July 2015 and August 2021. Patients were prospectively enrolled and received either an arthroscopic Latarjet procedure or an arthroscopic iliac crest graft transfer. Standardized follow-up after 6 months and mimimum 24 months included range of motion, Western Ontario stability index (WOSI), Rowe score and subjective shoulder value (SSV). All complications were recorded. RESULTS: 177 patients (group Latarjet procedure: n = 110, group iliac crest graft: n = 67) were included in the study. WOSI (n.s.), SSV (n.s.) and Rowe score (n.s.) showed no difference at final follow-up. 10 complications were seen in group Latarjet procedure and 5 in group iliac crest graft; the frequency of complications did not differ between the two groups (n.s.). CONCLUSION: The arthrosopic Latarjet procedure and arthroscopic iliac crest graft transfer lead to comparable results regarding clinical scores, frequency of recurrent dislocations and complication rates. LEVEL OF EVIDENCE: Level II.

Shoulder complaints and incidence of shoulder pathologies after contralateral major amputation in the mid and long-term.

INTRODUCTION: Amputations of the upper extremity are rare but present a life-altering event that is accompanied with considerable restrictions for the affected patients. Even with functional prosthesis, tasks of the amputated limb are usually transferred to the unaffected arm which could result in complaints of the unaffected shoulder in the mid and long term. We therefore aimed to investigate musculoskeletal pain and morphological degenerative changes of the shoulder following a contralateral amputation. MATERIALS AND METHODS: We included all patients with a major amputation treated at our institution with a minimum of three years since the amputation. All patients received an MRI of both shoulders and were investigated using validated scores for the upper extremity and physical activity (SSV, ASES, DASH, GPAQ, SF-36). Results of the MRIs were investigated for morphological changes by two blinded investigators comparing the side of the amputation and the unharmed upper extremity and results were correlated to the time since amputation and their physical activity. RESULTS: A total of 20 patients with a mean age of 56 ± 19.9 years (range, 23-82 years) could be included in the study. The mean time since the amputation was 26.3 ± 19 years (range, 3-73 years). On the unharmed upper extremity, the mean SSV was 61.9 ± 24.6, the mean ASES-Score 54.5 ± 20.3, the Constant-score of 63.7 ± 40.4 and a DASH-score of 47.6 ± 23.8. The MRI of the unharmed shoulder showed significant more full-thickness rotator cuff tears and joint effusion compared to the side of the amputation. Significant differences in the degree of a glenohumeral arthritis, AC-joint arthritis, or partial rotator cuff tears could not be found between shoulders. CONCLUSION: Amputations of the upper extremity are associated with a high disability of the unharmed upper extremity and more full thickness rotator cuff tears compared to the side of the amputation. However, the small number of patients and rotator cuff injuries should be kept in mind when interpreting the data. LEVEL OF EVIDENCE: IV (retrospective case series).

Instability and results after non-operative treatment of large anterior glenoid rim fractures: is there a correlation between fragment size or displacement and recurrence?

INTRODUCTION: There is little data available on non-operative treatment of anterior glenoid rim fractures (GRF). Nothing is known about fracture size and displacement in comparison to clinical outcomes and instability in a mainly middle-aged patient population. The aim of this study was to demonstrate the results of non-operative treatment in anterior glenoid rim fractures with the special focus on potential instability/recurrence. METHODS: The inclusion criteria were non-operatively treated anterior GRF of at least ≥ 5 mm width using the age- and gender-matched Constant/Murley score (a.-/g.-CMS) and the Western Ontario Instability Index (WOSI). Radiographic parameters (fracture morphology, displacement, major tuberosity fractures and Hill-Sachs lesion using initial CT and radiographs) and the proportion of the fractured glenoid were detected (2D-CT-circle-method) and osteoarthritis (A.P. and axial radiographs) was classified according to Samilson/Prieto. Proportion of fractured glenoid and medial displacement were correlated with the recurrence rate and the clinical scores. RESULTS: N = 36 patients could be followed-up after a mean of 4.4 years [12-140 month, average age: 58 (± 13, 33-86) years]. The a.-/g.-CMS was 93 (± 11, 61-100) points, and the WOSI was 81% (± 22%, 35-100%) on average. The mean intraarticular displacement was 4 mm (± 3 mm; 0-14 mm). The 2D-circle-method showed a mean glenoid fracture involvement of 21% (± 11, 10-52%). Two cases of frozen shoulders and one case with biceps pathology were associated with the trauma. Within the followed-up patient group re-instability has occurred in n = 2 patients (6%) within the first two weeks after trauma. Osteoarthritis was found in n = 11 cases. There was no correlation between the scores and the fracture size/displacement [(a.-/g.-CMS vs. displacement: r = - 0.08; p = 0.6; vs. size: r = - 0.29; p = 0.2); (WOSI vs. displacement: r = - 0.14; p = 0.4; vs. size: r = - 0.37; p = 0.06)], but very large (≥ 21%) fractures with displacement ≥ 4 mm showed slightly worse results without significant difference (a.-/g.-CMS p = 0.2; WOSI p = 0.2). The apprehension test was negative in all patients at final follow-up. CONCLUSION: Non-operative treatment of anterior GRF was associated with overall good results within a mainly middle-aged larger patient group. Re-instability is rare and is not associated with fragment size but can occur in the first weeks after trauma. Size and dislocation of the fracture is not a criterion for the prognosis of potential instability. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Accuracy of radiographic measurement techniques for the Taylor spatial frame mounting parameters.

AIM: The correction accuracy of the Taylor Spatial Frame (TSF) fixator depends considerably on the precise determination of the mounting parameters (MP). Incorrect parameters result in secondary deformities that require subsequent corrections. Different techniques have been described to improve the precision of MP measurement, although exact calculation is reportedly impossible radiologically. The aim of this study was to investigate the accuracy of intraoperative and postoperative radiographic measurement methods compared to direct MP measurement from TSF bone mounting. METHODS: A tibial Sawbone® model was established with different origins and reference ring positions. First, reference MPs for each origin were measured directly on the frame and bone using a calibrated, digital vernier calliper. In total 150 MPs measured with three different radiographic measurement techniques were compared to the reference MPs: digital radiographic measurements were performed using soft-copy PACS images without (method A) and with (method B) calibration and calibrated image intensifier images (method C). RESULTS: MPs measured from a non-calibrated X-ray image (method A) showed the highest variance compared to the reference MPs. A greater distance between the origin and the reference ring corresponded to less accurate MP measurements with method A. However, the MPs measured from calibrated X-ray images (method B) and calibrated image intensifier images (method C) were intercomparable (p = 0.226) and showed only minor differences compared to the reference values but significant differences to method A (p < 0,001). CONCLUSION: The results demonstrate that MPs can be accurately measured with radiographic techniques when using calibration markers and a software calibration tool, thus minimizing the source of error and improving the quality of correction.

Anatomical repair and ligament bracing of Schenck III and IV knee joint dislocations leads to acceptable subjective and kinematic outcomes.

PURPOSE: The aim of this study was to analyze the outcomes of anatomical repair and ligament bracing for Schenck III and IV knee dislocation (KD). METHODS: The results of 27 patients (15 and 12 cases of Schenck III and IV KD, respectively) after a mean follow-up of 18.1 ± 12.1 months (range 6-45 months) were retrospectively reviewed. Twenty-two patients suffered high-kinetic-energy accidents, whereas five patients suffered ultralow-velocity (ULV) trauma due to obesity. The outcome measures were the Lysholm score, Hospital for Special Surgery (HSS) knee score, Knee Society Score (KSS), Knee Injury and Osteoarthritis Outcome Score (KOOS) and Short Form 36 (SF-36) score. A kinematic 3D gait analysis with five walking trials was performed to compare the patients and healthy controls. RESULTS: The mean KSS, HSS score, Lysholm score, and KOOS were 77.4 ± 14.4, 84.6 ± 11.2, 81.5 ± 10.4, and 67.3 ± 16.8, respectively. No intra- or postoperative complications occurred. The mean range of motion deficiency compared to the healthy side was 24.4 ± 18.5°. Ten patients had first-degree residual laxity of the anterior cruciate ligament; 12 and 2 patients had first- and second-degree residual laxity of the collateral ligament, respectively. Five patients underwent additional arthroscopic arthrolysis due to arthrofibrosis at an average of 6.2 ± 1.9 months (range 4-9 months) after the initial surgery. The 3D gait analysis showed no major differences in joint stability or movement between the patients and healthy controls. Only the ULV trauma patients had significantly lower outcome scores and showed larger kinematic deviations in joint movement during the gait analysis. CONCLUSION: Anatomical repair with ligament bracing is a suitable surgical procedure in the treatment of KD and provides evidence in clinical practice with the benefit of early, definitive repair and preservation of the native ligaments. Patients reach acceptable subjective and objective functional outcomes, including mainly normalized gait patterns during short-term follow-up, with only minor changes in kinematics and spatial-temporal characteristics. Obese patients who suffered ULV trauma showed significantly inferior outcomes with larger deviations in joint kinematics. LEVEL OF EVIDENCE: Level III.

Radial head fractures with interposed capitellar cartilage fragment-hindrance to bone healing-a case series.

INTRODUCTION: Radial head fractures account for the majority of bony elbow injuries. The individual treatment options have been described in detail. In some cases, however, an unusual concomitant injury occurs, which can significantly impede primary osteosynthesis and healing. This concomitant injury can be an interposing cartilaginous capitellar fragment. METHODS: This retrospective study describes four cases of trapped cartilage fragments of the capitellum that compromised primary osteosynthesis or primary conservative healing of a radial head fracture. Radiological imaging, function and pain level are presented pre- and postoperatively (mean follow-up 9.25 months). RESULTS: None of the four cases showed preoperative evidence of an incarcerated cartilage fragment of the capitellum. They all showed limited elbow range of motion. CT examinations were performed in all cases. In each case, the cartilage fragment was first sighted upon surgery, subsequently removed and the fractures treated with ORIF. Mean follow-up was of 9.25 months. All fractures healed, with excellent function and low pain scores. CONCLUSIONS: This study presents rare cases of a trapped humeral cartilage fragment in radial head fractures. Radiological imaging including CT scans cannot reliably detect this concomitant injury. Therefore, this problem becomes apparent and treatable only during surgery. A high degree of suspicion is necessary especially in patients with minimally displaced fractures associated with limited elbow motion and a gap at the fracture site as treating these injuries conservatively may lead to poor outcome.

Biomechanical comparison of screw osteosyntheses and anatomical plating for coronoid shear fractures of the ulna.

INTRODUCTION: Among the few techniques described for the treatment of coronoid fractures, osteosynthesis techniques include screw osteosynthesis from anterior to posterior (AP) or from posterior to anterior (PA) and plate osteosynthesis. The aim of this study was to test the biomechanical stability of screw osteosynthesis and plate osteosynthesis using anatomical plates in coronoid process fractures. MATERIALS AND METHODS: On a total of 25 biomechanical synthetical ulnae, a coronoid shear fracture including 70% of the coronoid height was simulated. Osteosynthesis was then performed using two 2.7 mm screws from anterior, posterior and with use of three different anatomical plates of the coronoid process. For the biomechanical testing, axial load was applied to the fragment with 1000 cycles from 5 to 250 N, load to failure and load at 100 µm displacement. Displacements were measured using a point-based three-dimensional motion analysis system. RESULTS: Osteosynthesis using the PA-screw showed significant more displacement during cyclic loading compared with all other osteosyntheses (0.99 mm), whereas AP-screw showed the smallest displacement (0.10 mm) during cyclic loading. The PA-screw technique showed a significant lower load to failure compared to all other osteosynthesis with the highest load in AP-screw osteosynthesis. The load for 100 µm displacement was the smallest in PA-screw with a significant difference to the AP-screw and one plate osteosynthesis. CONCLUSION: Osteosynthesis of large coronoid shear fractures with two small-fragment screws from anterior allows stable fixation that is not inferior to anterior plate osteosynthesis and might be an alternative in specific fracture types. Posterior screw fixation was found as the weakest fixation method. LEVEL OF EVIDENCE: Basic science study.

Treatment of aseptic nonunion after medial opening-wedge high tibial osteotomy.

BACKGROUND: Nonunion after medial opening-wedge high tibial osteotomy (OWHTO) is a rare but serious complication with very limited data regarding its treatment. The aim of this study was to analyze the healing rate after operative treatment of nonunion after OWHTO. METHODS: We performed a single-center, retrospective study that included 14 patients with nonunion after OWHTO between 2010 and 2018. The treatment for all patients consisted of local debridement and cancellous bone grafting at the osteotomy gap. Revision osteosynthesis due to a loss of correction/loosening of the locking screws or plates was performed in 5 patients. In 7 patients, lateral hinge fractures were treated with additional lateral plating. Union was confirmed using the modified "Radiographic Union Score for Tibial fractures". Outcome measure was the Lysholm Knee Score at final follow-up. RESULTS: The mean age of the patients included in our study was 48.4 ± 6.7 years. Three patients were female (21.4%). The mean follow-up period was 20.8 ± 12.8 months. Union was achieved in 12/14 patients (85.7%) after a mean of 6 months (range, 3-13). The mean Lysholm Knee Score at the final follow-up was 83.2 ± 11.6. Two patients did not reach definitive union during the follow-up. In one patient, an infection of the nonunion following bone grafting was successfully treated with a two-stage procedure. Two patients needed additional cancellous bone grafting 6 and 8 months after the first revision surgery. All patients showed pain-free full weight bearing after union was achieved. CONCLUSIONS: Nonunions after OWHTO can generally be treated successfully with cancellous bone grafting. For patients who have loss of correction, loosening of the osteosynthetic material or fracture of the lateral hinge, an additional revision or additive osteosynthesis may be required. LEVEL OF EVIDENCE: Grade III.

Comparative proteomic analysis of osteogenic differentiated human adipose tissue and bone marrow-derived stromal cells.

Mesenchymal stromal cells are promising candidates for regenerative applications upon treatment of bone defects. Bone marrow-derived stromal cells (BMSCs) are limited by yield and donor morbidity but show superior osteogenic capacity compared to adipose-derived stromal cells (ASCs), which are highly abundant and easy to harvest. The underlying reasons for this difference on a proteomic level have not been studied yet. Human ASCs and BMSCs were characterized by FACS analysis and tri-lineage differentiation, followed by an intraindividual comparative proteomic analysis upon osteogenic differentiation. Results of the proteomic analysis were followed by functional pathway analysis. 29 patients were included with a total of 58 specimen analysed. In these, out of 5148 identified proteins 2095 could be quantified in >80% of samples of both cell types, 427 in >80% of ASCs only and 102 in >80% of BMSCs only. 281 proteins were differentially regulated with a fold change of >1.5 of which 204 were higher abundant in BMSCs and 77 in ASCs. Integrin cell surface interactions were the most overrepresented pathway with 5 integrins being among the proteins with highest fold change. Integrin 11a, a known key protein for osteogenesis, could be identified as strongly up-regulated in BMSC confirmed by Western blotting. The integrin expression profile is one of the key distinctive features of osteogenic differentiated BMSCs and ASCs. Thus, they represent a promising target for modifications of ASCs aiming to improve their osteogenic capacity and approximate them to that of BMSCs.

Secondary purulent infections of the elbow joint: a retrospective, single-center study.

BACKGROUND: Septic arthritis of the elbow joint is a rare condition. Limited data is available on infections of the elbow joint following trauma or prior surgery on this joint. The aim of this study was to describe the etiology, comorbidities, bacterial spectrum and therapy of secondary purulent elbow infections. METHODS: Patients treated in our hospital were selected through retrospective chart review between 2006 and 2015. We included all patients with an empyema of the elbow after a trauma or surgical intervention on this joint. 30 patients between 26 and 82 years (mean: 52.47) were included. RESULTS: Seven patients (23.3%) were female, 23 (76.7%) male. 22 patients (73.3%) had a history of trauma, eight (26.7%) had prior elective surgeries on their elbow. Between one and 25 surgeries (mean: 5.77) were necessary for treatment. In nine patients, debridement and synovectomy were sufficient, eight patients (26.7%) received resection of the elbow joint. One patient was treated with a chronic fistula. In 18 patients (60%), cultures of aspiration/intraoperative swabs were positive for Staphylococcus aureus, four of these were methicillin-resistant. Four patients (13.3%) had positive cultures for Staphylococcus epidermidis, in five patients (16.7%) no bacteria could be cultured. CONCLUSIONS: Secondary infections of the elbow joint are a rare disease with potentially severe courses, requiring aggressive surgical treatment and possibly severely impacting elbow function. Staphylococcus aureus was the most common bacteria in secondary infections and should be addressed by empiric antibiotic treatment when no suspicion for other participating organisms is present.

Pullout strength and failure mode of industrially manufactured and self-made all-suture anchors: a biomechanical analysis.

BACKGROUND: This study presents a new technique for assembling an all-suture anchor from existing medical products. The biomechanical characteristics of this self-made anchor (SMA) are compared with those of an industrially manufactured all-suture anchor. METHODS: The SMAs were made from established medical products (FiberWire #2 and 2-mm FiberTape; Arthrex, Naples, FL, USA). Pretesting was performed in biphasic polyurethane foam blocks. In the next step, 10 SMAs and 10 industrially made anchors (IMAs; 1.8-mm double-loaded Y-Knot Flex all-suture anchor; ConMed Linvatec, Largo, FL, USA) were applied with an insertion tool and tested in fresh porcine femora using a servohydraulic testing system, with a preload of 10 N and a displacement rate of 12.5 mm/s. Pullout strength and failure mode were recorded. RESULTS: The mean load at failure in the foam blocks was 459 ± 124 N in the SMA group and 538 ± 83 N in the IMA group. In porcine bone, failure occurred at 461 ± 102 N in the SMA group and 431 ± 135 N in the IMA group. The differences in pullout strength between the 2 types of anchor were not statistically significant, either in the foam blocks (P = .17) or in porcine bone (P = .62). CONCLUSION: A handmade all-suture anchor using 2 high-strength sutures woven into a 2-mm strip of high-strength tape did not show statistically different failure loads in polyurethane foam or in porcine metaphyseal bone in comparison with a commercially produced double-loaded all-suture anchor. The principal mode of failure in porcine bone in both groups was anchor pullout.

Surgical revision of radial head fractures: a multicenter retrospective analysis of 466 cases.

BACKGROUND: Radial head fractures lead to persisting disability in a considerable number of cases. This study aimed to investigate their most common revision causes and procedures. METHODS: This multicenter retrospective study reviewed the cases of 466 adult patients who had undergone surgical revision after operative or nonoperative treatment of a radial head fracture. The initial diagnosis was a Mason type I fracture in 13.0%, Mason type II fracture in 14.6%, Mason type III fracture in 22.8%, Mason type IV fracture in 20.9%, terrible-triad injury in 12.8%, Monteggia-like lesion in 13.1%, and Essex-Lopresti lesion in 2.0%. Initial treatment was nonoperative in 30.2%, open reduction and internal fixation (ORIF) in 44.9%, radial head arthroplasty in 16.6%, radial head resection in 3.7%, sole treatment of concomitant injuries in 2.6%, and fragment excision in 2.0%. Up to 3 revision causes and procedures were recorded per case. RESULTS: The most common complications were stiffness (67.4%), instability (36.5%), painful osteoarthritis (29.2%), ORIF related (14.8%), nonunion or necrosis (9.2%), radial head arthroplasty related (7.5%), ulnar neuropathy (6.0%), and infection (2.6%). Revision procedures frequently included arthrolysis (42.1%), arthroplasty (24.9%), implant removal (23.6%), ligament repair or reconstruction (23.0%), débridement (14.2%), repeated ORIF (8.2%), and/or radial head resection (7.7%). Mason type I or II fractures were primarily revised because of stiffness and painful osteoarthritis. Complications after Mason type III fractures were predominantly ORIF related. Fracture-dislocations showed a wide range of complications, with instability and stiffness comprising the most common causes of revision. CONCLUSIONS: The complications of radial head fractures are characteristic to their classification. Knowledge of these findings might guide surgeons in treating these injuries and may help counsel patients accordingly.

Semitendinosus autograft augmentation after bilateral patellar tendon re-rupture: a case report and technique note.

BACKGROUND: Acute bilateral patellar tendon rupture is a rare occurrence, especially in young patients in the absence of comorbidities. We describe a case of bilateral patellar tendon re-rupture in a young patient without predisposing factors. Further, we explain a technique for autograft augmented patellar tendon repair with bidirectional fixation using an ipsilateral semitendinosus graft in transosseous patellar and tibia bone tunnels. CASE PRESENTATION: We present the case of a 40-year-old healthy worker with bilateral acute on chronic patellar tendon rupture maintained following initial trauma and Krackow repair 2 years ago. He underwent bilateral reconstruction using semitendinosus autograft. At 1 year postoperatively, he has maintained the full range of motion and strength without re-rupture. CONCLUSION: This is the first case describing a new fixation technique after bilateral patellar tendon re-rupture. The use of semitendinosus autograft for reconstruction of the patellar tendon after re-rupture is a viable and effective option.

[Correction of posttraumatic deformities of the distal tibia with focal dome osteotomy]. / Korrektur posttraumatischer Fehlstellungen der distalen Tibia mithilfe der fokalen Domosteotomie.

BACKGROUND: Supramalleolar deformities require surgical correction to avoid posttraumatic osteoarthrosis of the knee or ankle joint and to prevent definitive treatment options, such as total ankle arthroplasty or arthrodesis of the ankle joint. Various methods for the operative correction of supramalleolar deformities have been described in the literature. OBJECTIVE: What results can be achieved with focal dome osteotomy to correct posttraumatic supramalleolar deformities? MATERIAL AND METHODS: A total of 10 patients (mean age 37 years) with a supramalleolar posttraumatic deformity were treated by focal dome osteotomy. The mean follow-up was 27 months (min. 6, max. 105 months), 5 patients were female and 5 male. The supramalleolar varus/valgus deformity was on average 20° (at least 12°, maximum 33°). Preoperative and postoperative mechanical axis and joint angles were determined on digital radiographs. The American Orthopedic Foot and Ankle Society (AOFAS) score was used to assess the clinical outcome. RESULTS: In seven patients the anatomical leg axis could be restored. In three patients a residual deformity of 2.8° was observed. Bone grafting was not necessary in any of the cases. Of the patients eight had free ankle mobility and two showed an average movement limit of 30° compared to the contralateral side. Posttraumatic ankle arthrosis was not observed in the short-term and medium-term results. The mean AOFAS score of 80 points (minimum 70, maximum 98) documented a functionally good result. CONCLUSION: Supramalleolar dome type osteotomy is a technically difficult method for acute correction of supramalleolar deformities. The functional results and complication rates are comparable to those in the literature for alternative osteotomy techniques.

Infection following fractures of the proximal tibia - a systematic review of incidence and outcome.

BACKGROUND: To systematically review all available studies of operatively treated proximal tibia fractures and to report the incidence of superficial or deep infection and subsequent outcomes. METHODS: A systematic review of the literature in Medline, Cochrane, Embase and GoogleScholar was conducted to identify studies with cohorts of patients with infection after surgical treatment of proximal tibia fractures. Studies were included according to predefined inclusion and exclusion criteria. The studies were analysed for methodological deficiencies and quality of outcome reporting based on the Level of Evidence (LOE) and Coleman Methodology Scoring (CMS.) RESULTS: In total 32 studies were included. There was heterogeneity between the studies, in terms of subject of the studies, outcome criteria, fracture type and classification, surgical techniques and length of follow-up. Therefore, no meta-analysis could be performed. The average CMS was 54.2 (range 36-75). The included studies were 25 case series (LOE IV), 6 were prospective cohort studies (LOE III) and one was a prospective randomized trial (LOE I). 203 (12.3%, range: 2.6-45.0%) infections occurred in the overall population (n = 2063). Those were divided into 129 deep infections and 74 superficial infections. Revision due to infection was reported in 29 studies, microbiological results in 6, respectively. 72 (55,8%) of 129 cases reporting outcome after deep infection had an unsatisfactory outcome with substantial limitations of the affected joint and leg. CONCLUSIONS: Postoperative infections are a challenge, sometimes requiring several revisions and often with a worse outcome. Further studies with structured study protocols should be performed for a better understanding of risk factors to improve treatment outcomes.

Biomechanical analysis of anterior bone graft augmentation with reversed shoulder arthroplasty in large combined glenoid defects compared with total bony joint line reconstruction (modified bony-increased-offset reversed shoulder arthroplasty).

BACKGROUND: The aim of this biomechanical study was to compare 2 surgical techniques for the reconstruction of large, combined, uncontained glenoid defects with reversed shoulder arthroplasty (RSA). METHODS: Three groups of scapulae with RSA were tested by the application of a physiological combination of compressive/shear loads in Sawbones (Pacific Research Laboratories, Inc., Vashon Island, WA, USA) and cadavers. Two of the groups (both Sawbones and cadaveric specimens) consisted of anterior combined defects (14 mm in depth), and the third group served as a control group (only Sawbones specimens). The first group with an anterior combined defect was reconstructed with anterior bone grafts to contain the defect and cancellous bone to fill the central defect before RSA with partial bony joint line reconstruction (p-BJR). In the second group with an anterior combined defect, the dorsal rim was reamed and the joint line was reconstructed with a bone disc fully covering the peg. This total BJR (t-BJR) corresponds to the technique of bony-increased-offset-RSA (BIO-RSA). RESULTS: At 150 µm of displacement, the loadings in the inferior-superior (IS) direction were significantly more stable than those in the anterior-to-posterior (AP) direction within both reconstructed defect groups (P ≤ .002). In contrast, no significant differences were found between the partial BJR and t-BJR group in either direction (Sawbones: AP: P = .29; IS: P = .44; cadavers: AP: P = .67; IS: P = .99). The control group revealed significantly higher values in all loadings of the IS direction and significantly higher loadings at 40 µm and 150 µm in the AP direction. CONCLUSION: Both techniques could be applied for such complex defects provided that there is sufficient medial bone stock for a t-BJR. Significantly greater stability was found in the IS direction than in the AP direction within each group, which could be explained by the longer screw anchoring within the superior and inferior columns. Both defect groups were less stable than the group of intact glenoids.

[Basic principles of fracture healing]. / Grundlagen der Knochenbruchheilung.

BACKGROUND: In contrast to other tissues, bone has the remarkable ability to heal without scarring. After union of the fracture, the remodeled bone ideally does not differ from the original bone, especially in terms of biomechanical properties. The healing of a fracture resembles the embryonic development of bone. Depending on the biomechanical properties of the fracture, bone heals directly or indirectly, which refers to the formation of cartilage as a step before new bone appears. Currently, treatment of the patient is often limited to anatomical reduction and optimization of the fracture environment with respect to biomechanics. PROSPECTS: Future treatment strategies, however, could include systemic medication that could be especially beneficial for patients at risk of complications in fracture healing. The aim of this review is to provide an overview on the process of fracture healing and to depict possibilities for current and future treatment strategies.

Anterior augmentation plating of aseptic humeral shaft nonunions after intramedullary nailing.

INTRODUCTION: Humeral shaft nonunion after intramedullary nailing is a rare but serious complication. Treatment options include implant removal, open plating, exchange nailing and external fixation. The objective of this retrospective study was to determine whether augmentation plating without nail removal is feasible for treating a humeral shaft nonunion. MATERIALS AND METHODS: Between 2002 and 2014, 37 patients (mean age 51, range 20-84 years) with aseptic humeral shaft nonunions prior to intramedullary nailing were treated with augmentation plating. The initial fractures had been fixed with retrograde nails (10 cases) or anterograde nails (27 cases). There were 34 atrophic nonunions and 3 hypertrophic nonunions. Nonunion treatment of all patients consisted of local debridement through an anterior approach to the humerus and anterior placement of the augmentation plates. Supplemental bone grafting was performed in all atrophic nonunion cases. All patients were followed until union was radiologically confirmed. RESULTS: Union was achieved in 36 patients (97 %) after a mean of 6 months (range 3-24 months). There was one case of iatrogenic median nerve palsy that showed complete spontaneous recovery 6 weeks postoperatively. One patient sustained a peri-implant stress fracture that was treated successfully by exchanging the augmentation plate to bridge the nonunion and the fracture. No infections or wound healing complications developed. At a mean follow-up of 14 months, all patients showed free shoulder and elbow motion and no restrictions in daily or working life. CONCLUSIONS: The results indicate that augmentation plating using an anterior approach is a safe and reliable option for humeral shaft nonunions after failed nailing, and the treatment has no substantial complications. Because the healing rates are similar to the standard technique of nail removal and fixation by compression or locking plates, we consider this technique to be an alternative choice for treatment.

Plasma clots gelled by different amounts of calcium for stem cell delivery.

PURPOSE: Freshly prepared autologous plasma clots may serve as a carrier matrix for expanded multipotent mesenchymal stromal cells (MSCs) or bone marrow cells. By varying the calcium concentration, plasma clots with different properties can be produced. The purpose of this in vitro study was to determine the optimal calcium concentrations for the clotting process, intra-clot cell viability, and clot lysis. METHODS: Different plasma clots were prepared by adding an equal volume of RPMI1640 (with or without MSCs) to citrate plasma (either containing platelets or platelet-free). Clotting was initiated by the addition of CaCl(2) (10 g/100 ml H(2)O, 10 % solution). The final concentration of CaCl(2) ranged from 1 to 10 % by volume of plasma. Viability and distribution of the MSCs were analysed by calcein-AM/propidium iodide staining. MSC-embedded plasma clots were dissolved with trypsin (0.25 %), and recovered cells were further incubated for 1 week under cell culture conditions. RESULTS: The viability of MSCs embedded in clots formed by the addition of 1-8 % by volume CaCl2 was not affected by incubation of up to 1 week. In contrast, clots produced by higher volumes of CaCl(2) solutions (9-10 % by volume of plasma) showed decreased numbers of viable cells. Intra-clot cell proliferation was highest in clots produced by addition of 5 % CaCl(2) by plasma volume. Osteocalcin release was not influenced in platelet-free plasma but decreased in platelet-containing plasma. Morphological analysis of stained recovered MSCs revealed that lysis of the plasma clot did not affect cell morphology or subsequent spontaneous proliferation. CONCLUSIONS: Clot formation and clot stability can be controlled by changing the concentration of CaCl(2) added to plasma. The addition of 5 % CaCl(2) produced a plasma clot with optimal results for stem cell delivery.

Ilizarov external frame technique for pirogoff amputations with ankle disarticulation and tibiocalcaneal fusion.

BACKGROUND: The high rates of wound failure, persisting infection, and nonunion of the tibiocalcaneal arthrodesis are the main reasons why the Pirogoff ankle disarticulation is rarely used for limb salvage. Use of the Ilizarov external frame has increased our fusion rate. The purpose of this study was to review our experience with the use of the Ilizarov external frame as a technique for Pirogoff amputations with ankle disarticulation and tibiocalcaneal fusion. METHODS: Twenty-four patients (median age, 57.4 years; range, 29-76 years) underwent a Pirogoff amputation with Ilizarov external frame use between January 2004 and June 2011. The most common indications were gangrene with uncontrollable infection due to Charcot arthropathy or chronic osteomyelitis. Four patients had sustained crush injuries of the foot. All patients were clinically and radiographically followed for a minimum of 12 months. Additionally, 15 patients were evaluated using the Taniguchi rating scale for Pirogoff amputations after a mean follow-up of 44.9 months (range, 12-86 months). RESULTS: In 21 patients (87.5%), a well-healed Pirogoff stump was achieved after a mean external fixation time of 18.1 weeks (range, 12.7-26.6 weeks). Impaired vascular perfusion was found to be the limiting factor for successful wound healing and an overall successful Pirogoff amputation. According to the Taniguchi scale, 67% of the patients achieved good or excellent functional results. Fair (27%) and poor (6%) results were observed only in the diabetic patients. CONCLUSION: Using the Ilizarov external frame allowed safe fixation and a high success rate, even in neuropathic feet. The frame allowed for immediate weight-bearing and soft tissue control; however, frame-associated complications were common and could result in revision surgery. LEVEL OF EVIDENCE: Level IV, case series.