Sandra Boesmueller

Risk factors for humeral head necrosis and non-union after plating in proximal humeral fractures

AIM The aim of this study was to evaluate risk factors for the development of humeral head necrosis and non-union after proximal humeral fractures-in particular, general risk factors that exist independent of fracture type. MATERIALS AND METHODS This study included patients (n=154) treated for proximal humeral fracture by means of open reduction and internal fixation (ORIF) using the Philos plate at a single level I trauma centre between January 2005 and December 2013. Follow-up monitoring included radiographic examination before hospital discharge, and again at 6 weeks, 12 weeks, and 6 months after surgery. At a minimum follow-up time of 6 months, radiographs taken in the anteroposterior and axial projection were evaluated in regard to the development of humeral head necrosis, non-union, and secondary screw cut out. RESULTS A total of 154 patients (61 males, 93 females) were available for radiological checkup. Mean age was 55.8 years (range: 19-91 years). There were statistically significant correlations between the development of avascular necrosis (AVN) and fracture type, non-union and smoking, and screw cut out - as well as overall complication rate - and age. The time to surgery did not influence the risk for AVN or non-union, independent of fracture type. In this study population, the risk of developing non-union after ORIF was 3.9-fold higher in heavy smokers (i.e., >20 cigarettes per day). The risk for screw cut out was 4.1-fold higher in patients over 60 years of age, and the overall risk for complications was 3.3-fold higher. CONCLUSION The older the patient, the more carefully one must consider the decision between conservative and operative treatments. If surgical treatment is performed, screw length should be selected depending on the patients age. Heavy smokers must be informed preoperatively of the increased risk for bony non-union after ORIF.

Incidence, characteristics, and long-term follow-up of sternoclavicular injuries: An epidemiologic analysis of 92 cases.

BACKGROUND The majority of published studies concerning sternoclavicular injuries are case series or systematic reviews. Prospective studies on the subject are hindered by the low incidence of these lesions. The aims of the present study were to provide an overview of this rare entity compared with those described in the literature and to present the long-term clinical outcome. METHODS We performed a retrospective data analysis of all sternoclavicular injuries treated at a single Level I trauma center from 1992 to 2011. Long-term clinical outcome was assessed using the ASES [American Shoulder and Elbow Surgeons], SST [Simple Shoulder Test], UCLA [University of California-Los Angeles] Shoulder Scale, and VAS [Visual Analog Scale] at latest follow-up. RESULTS We detected an overall incidence of 0.9% of sternoclavicular injuries related to all shoulder-girdle lesions. Ninety-two patients (52 males and 40 females) with a mean (SD) age of 39.2 (19.5) years (median, 41 years; range, 4–92 years) were included in this study. The main trauma mechanism was fall. Classification was performed according to Allman, the time point of treatment after initial trauma, and the direction of the dislocation. Nine patients of the 15 Grade III lesions were treated conservatively by closed reduction and immobilization, while four patients were treated surgically by open reduction and internal fixation. Forty-nine percent of the patients were available for long-term follow-up at a median of 11.3 years (range, 5.3–22.6 years) with a mean ASES score of 96.21, SST score of 11.69, UCLA score of 31.89, and VAS score of 0.47. CONCLUSION We found an overall incidence of 0.9% of sternoclavicular joint injuries related to all shoulder-girdle lesions and of 1.1% related to all dislocations, which is slightly lower compared with those described in the literature. Furthermore, we observed a high number of physeal sternoclavicular injuries with a percentage of 16% and overall good-to-excellent results at long-term follow-up. LEVEL OF EVIDENCE Epidemiologic study, level IV.

The arterial supply of the tendon of the long head of the biceps brachii in the human: A combined anatomical and radiological study

PURPOSE Arthroscopic repair of superior labral anterior to posterior (SLAP) lesions is often associated with a prolonged period of pain during the rehabilitation process. This might possibly be due to hypoxia in the biceps tendon anchor caused by sutures. The purpose of the study was to investigate the arterial supply of the long head of the biceps brachii tendon (LHBT) that may be impaired by surgery in the region of the biceps tendon anchor. METHODS On 20 human formalin-fixed bodies, the anterior circumflex humeral artery (ACHA) was located and followed into the intertubercular groove until it reached the LHBT. On 10 fresh-frozen anatomic specimens of the upper extremities, contrast medium was injected into the axillary artery, a 3D scan was performed, and multiplanar reconstructed (MPR) slices were generated. A set of maximum intensity projection (MIP) reconstructions from 10 computed tomography angiographies (CTA) of the upper extremities was used to confirm the findings of the 3D scan. RESULTS All anatomical dissections and radiological investigations revealed that the proximal portion of the LHBT was consistently supplied by an ascending branch of the ACHA. No artery was found to supply the biceps tendon anchor from the proximal aspect. CONCLUSIONS As the arterial supply of the LHBT is mainly provided by the ACHA, which enters the glenohumeral joint from the distal aspect, surgery at the bony origin of the LHBT may not interfere with this specific vessel.

Does an additional antirotation U-Blade (RC) lag screw improve treatment of AO/OTA 31 A1-3 fractures with gamma 3 nail?

INTRODUCTION Poor bone quality and unstable fractures increase the cut-out rate in implants with gliding lag screws. The U-Blade (RC) lag screw for the Gamma3® nail was introduced to provide monoaxial rotational stability of the femoral head and neck fragment. The purpose of this study was to evaluate whether the use of the U-Blade (RC) lag screw is associated with reduced cut-out in patients with OTA/AO 31A1-3 fractures. MATERIAL & METHODS Between 2009 and 2014, 751 patients with OTA/AO 31A1-3 fractures were treated with a Gamma3® nail at our institution. Out of this sample 199 patients were treated with U-blade (RC) lag screws. A total of 135 patients (117 female, 18 male) with standard lag screw (treatment group A) were matched equally regarding age (±4 years) sex, fracture type and location to 135 patients with U-blade (RC) lag screw (treatment group B). Within a mean follow up of 9.2 months (range 6-18 months) we assessed the cut-out rate, the calTAD, lag screw migration, the Parkers mobility score and the Parkers ratio at postoperatively, six and 12 months following surgery. Furthermore we recorded all complications, ASA-Score, hospital stay and duration of surgery retrospectively. RESULTS The most common fracture among group B with a cut-out of the lag screw were AO/OTA 2.3 and 3.2 fractures whereas in group A cut-out was most commonly seen in AO/OTA 2.1, 2.2 and 2.3 fractures, there was no significant reduction of the cut-out rate in group B 2.2% (n=3) compared to group A 3.7% (n=5). The duration of surgery was significantly shorter in group A (p<0.05). There was no significant difference in lag screw placement, the Parkers ratio and mobilization. CONCLUSION In our study the U-Blade (RC) lag screw did not reduce the cut-out in treatment of OTA/AO 31A1-3 fractures at all. Considering the longer duration of surgery and the higher costs of the U-Blade (RC) lag screw, our results do not justify its use. However, further prospective randomized studies will be necessary.

Neurofilament distribution in the superior labrum and the long head of the biceps tendon

BackgroundThe postoperative course after arthroscopic superior labrum anterior to posterior (SLAP) repair using suture anchors is accompanied by a prolonged period of pain, which might be caused by constriction of nerve fibres. The purpose was to histologically investigate the distribution of neurofilament in the superior labrum and the long head of the biceps tendon (LHBT), i.e. the location of type II SLAP lesions.MethodsTen LHBTs including the superior labrum were dissected from fresh human specimen and immunohistochemically stained against neurofilament (NF). All slides were scanned at high resolution and converted into tagged image file format, and regions of interest (ROIs) were defined as follows: ROI I—superior labrum anterior to the LHBT origin, ROI II—mid-portion of the superior labrum at the origin of the LHBT, ROI III—superior labrum posterior to the LHBT origin and ROI IV—the most proximal part of the LHBT before its attachment to the superior labrum. The entire images were automatically segmented according to the defined ROIs and measured using a programmed algorithm specifically created for this purpose. The NF-positive cells were counted, and their total size and the area of other tissue were measured separately for the different ROIs.ResultsDistribution of NF-positive cells in absolute numbers revealed a clear but insignificantly higher amount in favour of ROI I, representing the superior labrum anterior to the LHBT origin. Setting ROI I at 100%, a significant difference could be seen compared to ROI III, representing the superior labrum posterior to the LHBT origin (ROI I vs. ROI III with a p value < 0.05).ConclusionsSummarizing, the density of neurofilament is inhomogeneously distributed throughout the superior labrum with the highest number of neurofilament in the anterior superior labrum. Thus, suture placement in type II SLAP repair could play an important role for the postoperative pain-related outcome.

Matrix Production Affects MRI Outcomes After Matrix-Associated Autologous Chondrocyte Transplantation in the Knee

Background: Matrix-associated autologous chondrocyte transplantation (MACT) has been an effective therapy for large, full-thickness cartilage lesions for years. However, little is known about how graft maturation is affected by characteristics of transplanted chondrocytes. Purpose: To investigate the influence of gene expression of chondrocytes at the time of transplantation on MRI outcomes up to 2 years after MACT. Study Design: Case series; Level of evidence, 4. Methods: This study included 25 patients with 27 symptomatic traumatic defects of articular cartilage, who had undergone MACT in the knee. Postoperative MRI examinations were conducted at 3, 6, 12, and 24 months after surgery. Biochemical graft maturation was assessed by measuring T2 relaxation time values of the transplant and healthy native cartilage areas. The MOCART (magnetic resonance observation of cartilage repair tissue) score was used to evaluate the morphological quality of regeneration tissue. Gene expression (collagen type I, collagen type II, aggrecan, versican, and interleukin-1β) was determined by real-time polymerase chain reaction (PCR) in transplant residuals at the time point of transplantation and was correlated with MRI outcomes using Spearman’s rank correlation coefficient. A Friedman test with post hoc analysis (Wilcoxon signed rank test) conducted with a Bonferroni correction was applied to compare scores at different time points. Results: T2 relaxation time of regeneration tissue improved from a mean ± SD of 74.6 ± 20.1 milliseconds at 3 months to 47.9 ±13.3 milliseconds at 24 months (P < .003). These values were similar to the T2 relaxation times of the native surrounding cartilage (50.9 ± 15 ms). The calculated T2 index (ratio of regeneration tissue to native cartilage) improved from 1.63 ± 0.76 at 3 months to 1.0 ± 0.4 at 24 months (P < .011). The MOCART score increased from 51.6 ± 15 points to 72.4 ± 12.2 points (P < .001). Improvement of the T2 index over time significantly correlated with aggrecan, COL1A1, COL2A1, and versican expression (rs = 0.9, P < .001; rs = 0.674, P < .012; rs = 0.553, P < .05; and rs = 0.575, P < .04, respectively). No correlation was found for IL-1β. Conclusion: These data demonstrate that matrix production in transplanted chondrocytes affects maturation of MACT grafts in MRI 2 years after surgery.

Plate failure following plate osteosynthesis in periprosthetic femoral fractures.

SummaryBackgroundIncreasing numbers of total knee and hip arthroplasties result in a growing number of periprosthetic femoral fractures (PPFF). PPFF with a stable stem component are treated commonly with plate osteosynthesis. Therefore plate failure is seen as a major complication. The aim of this retrospective study was to investigate the patients’ outcome after plate failure.MethodsThe database of a Level 1 trauma center was searched for all patients treated for a PPFF with plate osteosynthesis. Patients with plate failure were investigated specifically. Standard demographic data, details on initial arthroplasty, trauma, and treatment were recorded for all patients. All fractures were classified and their outcome reviewed.ResultsSeven (8.8 %) out of 80 patients treated with plate osteosynthesis following PPFF met our inclusion criterion being plate failure. All these patients were female, with an average age at primary surgery of 74 ± 13 years and a mean follow-up of 885 days (range, 264–2549). Four patients suffered a PPFF after total hip arthroplasty (THA) (2 Vancouver Type B1 and 2 Type C) and three after total knee arthroplasty (TKA) (Lewis-Rorabeck Type II). Following plate failure, four patients healed uneventfully and three patients experienced complications such as pseudarthrosis, screw loosening, and further plate failure.ConclusionIn patients with poor bone quality, bone graft, bone cement, and bone biologics have to be considered in revision surgery. Furthermore, long-stem revision and tumor prosthesis are an additional solution.

The influence of sex and trauma impact on the rupture site of the ulnar collateral ligament of the thumb

Purpose and hypothesis Although sex- and gender-specific analyses have been gaining more attention during the last years they have rarely been performed in orthopaedic literature. The primary purpose of this study was to investigate whether for injuries of the UCL the specific location of the rupture is influenced by sex. A secondary study question addressed the sex-independent effect of trauma intensity on the rupture site of the UCL. Methods This study is a retrospective analysis of all patients with either a proximal or distal bony avulsion or with a mid-substance tear or ligament avulsion of the UCL treated surgically between 1992 and 2015 at two level-I trauma centres. Trauma mechanisms leading to the UCL injury were classified into the following categories: (1) blunt trauma (i.e., strains), (2) low-velocity injuries (e.g., fall from standing height, assaults), and (3) high-velocity injuries (e.g., sports injuries, motor vehicle accidents). After reviewing the surgical records, patients were divided into three groups, depending upon the ligament rupture site: (1) mid-substance tears, (2) proximal ligament or bony avulsions and (3) distal ligament or bony avulsions. Dependencies between the specific rupture site and the explanatory variables (sex, age, and trauma intensity) were evaluated using χ2 test and logistic regression analysis. Results In total, 1582 patients (1094 males, 488 females) met the inclusion criteria. Mean age was 41 years (range: 9–90 years). Taking into account the effects of sex on trauma intensity (p<0.001) and of trauma intensity on rupture site (p<0.001), mid-substance tears occurred more frequently in women, whereas men were more prone to distal ligament or bony avulsions (p<0.001). In other words, sex and rupture site correlated due to the effects of sex on trauma intensity and of trauma intensity on rupture site, but taking into account those effects there still was a significant effect of sex on rupture site. Conclusions The results of this study demonstrate that with regression analysis both sex and trauma intensity allow to predict rupture site in UCL injuries.

Damage control surgery – experiences from a level I trauma center

BackgroundThere is still no evidence in literature for damage control orthopaedics (DCO), early total care (ETC) or using external fixation solely in fractures of the long bones in multi-system-trauma. The aim of this study was to determine parameters influencing the choice of treatment in clinical routine (DCO, ETC, or EF) in femoral or tibial shaft fractures in combination with multi-system-trauma, severe soft tissue damage or both.MethodsData of 236 patients with 280 fractures of long bones of the lower extremities treated at a level I trauma center were analysed. Clinical parameters on arrival (age, sex [m/f], ISS, fracture site [femur/tibia], soft tissue damage [closed or open fractures according to the Gustilo-Anderson classification], pulmonary injury [yes/no]) were collected and analysed whether they influence the choice of upcoming treatment (DCO/ETC/EF).ResultsOur findings showed that high ISS and severe soft tissue damage (grade III) significantly correlated with DCO. High ISS, old age, female sex and fracture site (tibia) correlated with EF. This group of sole use of external fixation had highest rate of complications, 69% were associated with at least one complication.ConclusionSeverely injured patients are treated significantly more often with DCO or EF. The presence of higher ISS (≥16) and of type III open fractures increased the use of DCO. However, ISS, fracture-site, patient’s age, type III open fractures or sex (female) increased the use of EF compared to ETC.