Arthroplasty of the trapeziometacarpal joint with or without bioabsorbable polylactide scaffold (RegJoint™) interposition.

The RegJoint™, a bioabsorbable polylactide scaffold, was introduced in 2011 for scaphometacarpal interposition following trapeziectomy for osteoarthritis. As previous clinical trials provided controversial results, we aimed to prove the non-inferiority of RegJoint™ interposition. In this retrospective study, first metacarpal suspension arthroplasty alone (SA) was compared to suspension with RegJoint™ interposition (RJ). Thirty-four patients with 37 treated thumbs (SA: 14; RJ: 23) were assessed clinically and radiologically at a mean follow-up of 5.3 ± 2.6 years (SA: 7.96; RJ: 3.73). Patient-reported outcomes were measured on three questionnaires (DASH, PRWE and PEM) and a visual analogue pain scale; there were no significant differences between the 2 groups. Clinical assessment comprised range of motion, opposition, pain, first-ray length, hand span, prominence, instability, force and sensitivity to touch. The RJ group showed significantly better palmar abduction (p = 0.026); the other outcome parameters were comparable in the 2 groups. Follow-up radiographs showed osteolysis in 2 SA hands and 3 RJ hands (p = 0.551). First-ray length had decreased by a mean 4.7 ± 2.7 mm at follow-up (SA: -3.8; RJ: -5.2; p = 0.056). No signs of adverse tissue reactions were observed. We conclude that RegJoint™ spacers do not produce more complications than suspension alone but provide no added benefit.

Icing the Pain-Ultrasound-Guided Cryoablation of Symptomatic Post-Amputation Stump Neuroma.

PURPOSE: To assess the feasibility and outcome of ultrasound-guided cryoablation in patients with a sensitized stump neuroma after limb amputation. MATERIAL AND METHODS: Seven patients (3 females, 4 males; mean age 42 years) were included in this retrospective study. Ultrasound-guided cryoablation of a previously identified painful stump neuroma was performed. Pain was assessed on the visual analogue scale (VAS) and compared before and after cryoablation (Wilcoxon Test). The degree of pain alleviation was correlated with patient age, duration of pain before ablation and time interval between amputation and ablation (Spearman correlation). A p-value less than 0.05 was deemed statistically significant. RESULTS: Nine cryoablations were performed for 8 neuromas. Technical success was 100%, there were no major complications. Mean follow-up was 27 months. There was a statistically significant decrease of pain from mean 8.3 / 10 (baseline) to 4 /10 (on day one), 2.1 / 10 (at one week) and 3 / 10 (at last follow-up) (p < 0.05). Patient satisfaction with cryoablation treatment was very high (median score 70 / 100). CONCLUSION: In our small population observational study, ultrasound-guided cryoablation of a sensitized stump neuroma was effective and safe for pain alleviation with very good long-term results. LEVEL OF EVIDENCE: Level 2, Observational study with dramatic effect.

Osteoporosis is accompanied by reduced CD274 expression in human bone marrow-derived mesenchymal stem cells.

Underlying pathomechanisms of osteoporosis are still not fully elucidated. Cell-based therapy approaches pose new possibilities to treat osteoporosis and its complications. The aim of this study was to quantify differences in human bone marrow-derived mesenchymal stem cells (hBMSCs) between healthy donors and those suffering from clinically manifest osteoporosis. Cell samples of seven donors for each group were selected retrospectively from the hBMSC cell bank of the Trauma Department of Hannover Medical School. Cells were evaluated for their adipogenic, osteogenic and chondrogenic differentiation potential, for their proliferation potential and expression of surface antigens. Furthermore, a RT2 Osteoporosis Profiler PCR array, as well as quantitative real-time PCR were carried out to evaluate changes in gene expression. Cultivated hBMSCs from osteoporotic donors showed significantly lower cell surface expression of CD274 (4.98 % ± 2.38 %) than those from the control group (26.03 % ± 13.39 %; p = 0.007), as assessed by flow cytometry. In osteoporotic patients, genes involved in inhibition of the anabolic WNT signalling pathway and those associated with stimulation of bone resorption were significantly upregulated. Apart from these changes, no significant differences were found for the other cell surface antigens, adipogenic, osteogenic and chondrogenic differentiation ability as well as proliferation potential. These findings supported the theory of an influence of CD274 on the regulation of bone metabolism. CD274 might be a promising target for further investigations of the pathogenesis of osteoporosis and of cell-based therapies involving MSCs.

[Injuries of the biceps-labrum complex : Principles, pathologies and treatment concepts]. / Verletzungen des Bizeps-Labrum-Komplexes : Grundlagen, Pathologien und Behandlungskonzepte.

BACKGROUND: The biceps-labrum complex is prone to acute lesions and degenerative changes due to its anatomical structure and the high load it has to endure. Pathological changes of these structures are common pain generators and can significantly impair shoulder function. Anatomically, the biceps-labrum complex can be divided into three zones: inside, junction and bicipital tunnel. DIAGNOSTIC PROCEDURE: Despite the focused physical examination and advancements in imaging techniques, the exact localization of pathologies remains challenging. Arthroscopy can be used to accurately diagnose inside and junctional pathologies but extra-articular changes in the region of the bicipital tunnel can only be partially visualized. TREATMENT: In cases of unsuccessful conservative treatment and correct indications, a high level of patient satisfaction can be surgically achieved. In young patients an anatomical reconstruction of inside lesions or tenodesis of the long head of the biceps tendon is performed; however, even tenotomy is a valuable option and can achieve equally satisfactory results. Unaddressed pathological changes of the bicipital tunnel can lead to persistence of pain. In clinical procedures performing tenodesis, both the different techniques and the implants used have been found to show similar results. This article describes the anatomical principles, pathological changes, the focused clinical instrumental diagnostics and discusses the different treatment philosophies as well as the outcome according to the recent literature.

[Patient volume, diagnosis and injury mechanisms in a level 1 trauma center at the beginning of the COVID-19 pandemic in comparison to the mean of the 3 previous years : A retrospective, epidemiological evaluation of 4967 patients]. / Patientenaufkommen, Diagnosen und Verletzungsmechanismen eines überregionalen Traumazentrums mit Beginn der COVID-19-Pandemie im Vergleich zum Mittelwert der 3 Vorjahre : Eine retrospektive, epidemiologische Auswertung von 4967 Patienten.

BACKGROUND: As part of the COVID-19 pandemic, political decisions were made to reduce social interaction and to reduce the number of infections. The aim was to create capacities for the in-hospital care of the patients. OBJECTIVE: The aim of the study was to check whether a reduction in the number of trauma patients compared to the mean of the previous 3 years could be observed. MATERIAL AND METHODS: We retrospectively analyzed all patients who presented in the emergency admission from 1 March to 15 April 2020 with the mean of the patients from the previous 3 years 2017-2019. The age of the patients, time of presentation, diagnoses, whereabouts of the patients, inpatient or outpatient, number and duration of the operative care and required capacity on the normal ward and intensive care units (ICU) were recorded. The injury mechanism was also examined. RESULTS: A total of 4967 patients between 1 March and 15 April were included. On average over the 3 previous years, a total of 1348 patients, i.e. 29.3 patients per day were counted in our emergency room. In 2020 a total of 923, i.e. 20 patients per day (p < 0.01) were counted. On average 227 (24.6%) were admitted to hospital compared to 311.5 (23.1%) in 2020. On average 143 operations were performed compared to 136 in 2020. The days on the ward were reduced from 2442 on average for the previous years, in 2020 to 1172 days by 52.1% (p < 0.01). The number of days on the ICU was 450 days on average in previous years and 303 days in 2020 (-32.7%, p < 0.01). CONCLUSION: The number of patients in the emergency admission was significantly reduced in the observation period in 2020 compared to the mean of the previous 3 years. This directly made resources available for the care of COVID-19 patients.

[Minimally invasive stabilization of sacral fractures]. / Minimal-invasive Stabilisierung bei Frakturen des Sakrums.

BACKGROUND: Sacral fractures can be of traumatic origin and can also occur as insufficiency fractures. While the therapeutic target of mechanically stable insufficiency fractures is mainly pain relief, mechanically unstable insufficiency fractures and traumatic sacral fractures following high-energy trauma require biomechanical stabilization. Various surgical strategies are available for this, whereby minimally invasive techniques are now preferred whenever possible. OBJECTIVE: This article presents the clinical challenges and options for minimally invasive treatment of sacral fractures. MATERIAL AND METHODS: Selected important study data are discussed and our own treatment approach is presented. RESULTS: The most important minimally invasive techniques for operative treatment of sacral fractures are presented: sacroiliac screw osteosynthesis, lumbopelvic stabilization and sacroplasty. The selection of the surgical technique should be made on an individual basis. While sacroiliac screw osteosynthesis is the international gold standard, diverse authors have also published minimally invasive techniques for lumbopelvic stabilization. The latter enables a higher mechanical stability. In contrast, sacroplasty should only be used as an alternative treatment in insufficiency fractures. Comparative studies of the described techniques are still missing. CONCLUSION: All surgical options have their indications. Nevertheless, the biomechanical stability which can be achieved differs widely. Therefore, an exact analysis should be carried out of what is necessary with respect to reduction and retention and what should be achieved when treating sacral fractures.

Development of an intraoperative 3D C-arm technique for torsion control of femur fractures: a cadaver study.

AIM: This study aims to test the accuracy and feasibility of a measurement of femoral torsion of a 3D C-arm system (Linea aspera method) in a cadaver setting. MATERIALS AND METHODS: A total of 11 intact femora were used. Schanz screws were inserted in the femoral bone in a parallel manner with the help of a fixed drill sleeve. Femur bones were then fractured in a controlled manner and three different internal and external torsion angles were fixed with the help of a Goniometer. After that, a 3D scan was performed. The 3D data set was analyzed using a radiologic software (Visage 7, Visage Imaging Inc, USA). Measurements were then compared in the two methods with a dependent t test. RESULTS: Specific measurements for different angles did not show any differences between those two utilities. CONCLUSION: Intraoperative estimation of femoral antetorsion using a 3D C-Arm system and the Linea aspera method seems to be an accurate and feasible method. Nevertheless, more studies with higher patient numbers, comparison to CT seems to be the next step and can be recommended.

The rotational fixator: A new device.

OBJECTIVES: Malrotation after surgical treatment of femoral shaft fractures is a common problem and often leads to follow-up procedures with uncertain outcome. The aim of this study is the validation of a new device (Rotational Fixator) to perform the correction safely and accurately. METHODS: In an in-vitro study, we tested the Rotational Fixator on 21 corpse bones against a commercially available standard goniometer for measurement inaccuracies. For this purpose, we varied the rotation width from 10 to 30° in inside and outside rotation. RESULTS: We found a small measurement inaccuracy of 1-2° with increasing rotation. The smallest differences are found at 10° IR with 0.9524° (SD ± 1.0713; p = 0.001) difference and 10° ER with at 0.5952° (SD ± 0.6823; p = 0.001) difference and increase up to 30° (IR 1.6667°, SD ± 1.7121, p < 0.000/ER 1.5000°, SD ± 1.0488, p < 0.000). CONCLUSIONS: The measurement results of the device show a constant deviation from the gold standard but are constant in the measurement error and slightly in relation to the desired correction range, so that a further review of the device and further testing in in vivo studies makes sense. LEVELS OF EVIDENCE: Level 3.

[Typical alterations of frozen shoulder in MRI examinations]. / Typische Veränderungen bei der "frozen shoulder" in der bildgebenden MRT-Untersuchung.

Magnetic resonance imaging (MRI) is routinely used for the diagnostic assessment of diseases of the shoulder joint. Depending on the clinical presentation native imaging, intravenous (IV) or intra-articular injection of contrast medium can be performed (MR arthrography). Advances in imaging technology nowadays enable early detection of characteristic changes in the clinical picture of frozen shoulder. These changes typically include thickening of the coracohumeral ligament, the axillary pouch and the capsule at the rotator interval. Furthermore, obliteration of the subcoracoidal fat pad can also be observed. The MRI examinations also show a hyperintensity in the T2-weighted imaging and a contrast enhancement of the joint capsule. The alterations can show a temporal correlation with the clinical symptoms of the patient.

[3D-printing in trauma surgery : Planning, printing and processing]. / 3D-Druck in der Unfallchirurgie : Planung, Druck und Aufbereitung.

Possible use of 3D-printing technology in orthopedic surgery ranges from preoperative planning to dedicated counselling with patients by the use of individual 3D models, intraoperative surgery tools or implants and various other applications. This article describes a technique for the creation of intraoperative tools with which the process from computed tomography (CT) images to 3D-printed tools in trauma surgery can safely be administered. For segmentation of CT images a range of different software options is available. The standard triangulation file created in this way (file ending: .stl) must subsequently be post-processed. By the use of the digital casts from bone and fractures in computer-aided design (CAD) programs implants and patient individual tools are created, which can range from ortheses to protheses to intraoperative saw guides.

[Current concepts and new developments of 3D printing in trauma surgery]. / Aktueller Stand und neue Entwicklungen des 3D-Drucks in der Unfallchirurgie.

The use of 3D printing (synonyms "rapid prototyping" and "additive manufacturing") has played an increasing role in the industry for many years and finds more and more interest and application in musculoskeletal surgery, especially orthopedic trauma surgery.In this article the current literature is systematically reviewed, presented and evaluated in a condensed and comprehensive way according to anatomical (upper and lower extremities) and functional aspects. As many of the publications analyzed were feasibility studies, the degree of evidence is low and methodological weaknesses are obvious and numerous; however, this pioneering work is extremely stimulating and important for further development because the technical, medical and economic potential of this technology is huge and interesting for all those involved in the treatment of musculoskeletal problems.

[3D-printed template-assisted reduction of long bone fractures]. / 3D-Druck-Template-gestützte Reposition von Frakturen der langen Röhrenknochen.

INTRODUCTION: In multiply injured patients, the time period between the initial treatment with external fixators (damage control) and the definitive treatment can last from days to weeks. A poor reduction result with the fixator (e.g. malposition in axis, length and rotation) and a long delay from trauma to definitive osteosynthesis are associated with longer operation times, higher intraoperative radiation doses, higher infection rates and an increased likelihood for the necessity to perform an open reduction. MATERIAL AND METHODS: In the described technique computed tomography (CT) is performed after temporary stabilization of the long bone fracture by an external fixator. On the basis of a three-dimensional dataset the fracture can be virtually reduced and a patient-specific reduction fixator can be designed and printed. The 3D printed reduction fixator fits only in the reduced position of the fracture, thus maintaining anatomical bone alignment. The procedure was used for the first time in the Trauma Surgery Clinic of the Medical University Hanover in May 2018 in a polytraumatized female patient with severe brain injury and an open floating knee injury. RESULTS: The procedure could be performed for femoral and tibial shaft fractures. The postoperative CT showed a satisfactory reconstruction of length, torsion and frontal and sagittal plane alignment. Fracture healing was uneventful within 3 months. CONCLUSION: Severely injured patients who initially receive stabilization according to the damage control principle and subsequently remain in the intensive care unit, could particularly benefit from the described postoperative reduction technique. In addition, the reduction fixator can be helpful for the definitive treatment of patients with bilateral fractures of long bones, where a reference to a healthy side is not possible.

High complication and revision rates after total femoral replacement: a retrospective single center analysis of indication, function, and complication.

INTRODUCTION: Total femoral replacement (TFR) is a limb salvage procedure performed for large bony defects. However, it is often associated with major complications and reduced function. Data on limb preservation rates and functional outcomes after TFR are limited. The primary objective of this study is to assess indications, functional outcomes, and complications after TFR. MATERIALS AND METHODS: We retrospectively analyzed all patients after TFR between 2006 and 2016. All patients received a modular mega endoprosthesis (MUTARS®). Patients were grouped according to their initial indication for TFR: (1) fracture, (2) tumor, or (3) infection. We evaluated (i) patient survival, (ii) postoperative function with the Musculoskeletal Tumor Society Score (MSTS), knee strength, range of motion, and (iii) complications. RESULTS: Between 2006 and 2016, TFR was performed in 22 patients with a mean age of 64 +/-17 years. Indications for TFR were tumor (n = 6), infection (n = 8) and fracture (n = 8). The mean follow-up (f/up) was 18 months. At final follow-up, mean MSTS was 24%. Mean knee flexion strength was reduced 63% compared to the contralateral leg (p = 0.004). At time of final f/up, 5 patients (22%) died, 5 (22%) underwent secondary hip exarticulation, and 12 (54%) suffered a major complication. At f/up, 11 patients had infections. Of these 11 patients, 5 died, 4 were treated with debridement, and 5 were treated with hip exarticulation. Fifteen patients survived with preserved limbs at f/up. CONCLUSION: TFR is a salvage procedure with limited functional outcome and high complication rates. Nevertheless, the majority of our cohort could be treated successfully with limb salvage.