Sonographic Measurement of Dynamic Horizontal Instability in Acromioclavicular Joint Instability: Description of a Simple Technique and Correlation to Radiographic Parameters.

OBJECTIVE: Dynamic horizontal instability is considered to be the main reason for poor outcome after treatment for acromioclavicular (AC) joint instability. In this study, we describe a simple technique to quantify this pathology via sonography. METHODS: Thirty-six shoulders from 18 patients with ac joint instabilities were examined using modified Alexander views and a standardized sonographic examination. On the Alexander views, overlap of acromion and clavicle (OLAC), glenoid center to posterior clavicle distance (GCPC), and lateral extension (LE) were measured. Afterwards, the results were analyzed and compared with sonography. Posterior translation of the clavicle and the difference of translation between healthy and injured shoulder were evaluated. RESULTS: The mean age of the patients was 39 ± 14 years (range 19-61 years). We included 4 (22%) Rockwood type 3, 1 (6%) Rockwood type 4, and 13 (72%) Rockwood type 5 lesions. Four (22%) patients were female and 14 (78%) male patients. Posterior clavicle translation of the injured shoulder correlated strongly between OLAC and sonography (r = -0.514, P = .029), and the difference of translation between healthy and injured shoulder correlated very strongly between LE and sonography (r = 0.737, P < .001). CONCLUSION: The sonographic measurement technique for horizontal instability presented in this work could help detect horizontal instabilities. While the observation of dynamic horizontal displacement is a strength of this technique, measurements are hindered in cases of high coracoclavicular distances. LEVEL OF EVIDENCE: Level III-retrospective cohort study.

Elective shoulder surgery during the coronavirus disease 2019 pandemic in Germany: the patients' perspective.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has impeded the treatment of elective shoulder patients all over the world. Owing to the constraints in personnel and operation theater capacities, many patients who should undergo planned surgeries could not receive medical care. In our study, we examined the status quo of elective shoulder arthroscopy during the pandemic in Germany. METHODS: Using a nonprofit database, 40 shoulder units that performed the most arthroscopic rotator cuff repairs in Germany in 2018 were identified. Following a standardized protocol, the web pages of these units were screened, and their strategy for elective procedures during the COVID-19 pandemic was analyzed. Special emphasis was put on the use of new digital technologies. RESULTS: At the time of the study, no unit had stopped scheduling appointments for elective shoulder patients because of the pandemic. Almost all units (97.5%) offered explicit information about COVID-19 and their strategies toward it. The possibilities of visiting patients in shoulder units varied owing to local restrictions. Two units (5%) offered digital consultations. CONCLUSION: At the time of the study, elective shoulder procedures could be planned and carried out at the largest centers in Germany. Local restrictions had a great influence on the organization of the procedure and hospital stay during the COVID-19 pandemic. Digital consultations were not available in every unit.

Local osteo-enhancement of osteoporotic vertebra with a triphasic bone implant material increases strength-a biomechanical study.

PURPOSE: The aim of this study was to assess the biomechanical properties of intact vertebra augmented using a local osteo-enhancement procedure to inject a triphasic calcium sulfate/calcium phosphate implant material. METHODS: Twenty-one fresh frozen human cadaver vertebra (Th11-L2) were randomized into three groups: treatment, sham, and control (n = 7 each). Treatment included vertebral body access, saline lavage to displace soft tissue and marrow elements, and injection of the implant material to fill approximately 20% of the vertebral body by volume. The sham group included all treatment steps, but without injection of the implant material. The control group consisted of untreated intact osteoporotic vertebra. Load at failure and displacement at failure for each of the three groups were measured in axial compression loading. RESULTS: The mean failure load of treated vertebra (4118 N) was significantly higher than either control (2841 N) or sham (2186 N) vertebra (p < 0.05 for: treatment vs. control, treatment vs. sham). Treated vertebra (1.11 mm) showed a significantly higher mean displacement at failure than sham vertebra (0.80 mm) (p < 0.05 for: treatment vs. sham). In the control group, the mean displacement at failure was 0.99 mm. CONCLUSIONS: This biomechanical study shows that a local osteo-enhancement procedure using a triphasic implant material significantly increases the load at failure and displacement at failure in cadaveric osteoporotic vertebra.

Publication rate of abstracts presented at the Congress of the European Federation of National Associations of Orthopaedics and Traumatology (EFORT).

BACKGROUND: The publication rate of presented abstracts is an important parameter to assess the scientific quality of medical congresses. It has been investigated for many congresses in orthopaedics and traumatology, but until now, it has not been studied for the congress of the European Federation of National Associations of Orthopaedics and Traumatology (EFORT). The aims of this study were to determine: (1) the publication rate of the EFORT congress, (2) factors that favour publication of abstracts presented at the EFORT congress, (3) the consistency between the congress abstract and publication in relation to authorship. HYPOTHESIS: There are factors that favour publication of abstracts presented at the EFORT congress and there is a high consistency between the congress abstract and publication in relation to authorship. MATERIALS AND METHODS: All 1624 abstracts presented at the EFORT congress in 2011 were included in this study, to allow a 5-year period for publication after the congress. The characteristics of the abstracts presented were studied and the publication rate in peer-reviewed journals was determined using a Medline search. RESULTS: The publication rate for studies presented at the 2011 EFORT congress was 42% (677/1624 abstracts), with a mean of 16 months (-56 to 60 months) between congress and publication. The mean impact factor of the publications was 1.8 (0-7.6). A significantly higher publication rate was found for: oral presentations (52%; 322/617) versus posters (35%; 355/1007) (p<0.01), experimental studies (53%; 110/208) versus clinical studies (40%; 507/1254) (p<0.01), and studies with higher levels of evidence of I or II (59%; 144/244) versus studies with lower levels of evidence of III or IV (36%; 362/1005) (p<0.01). A new author was added in 59% (403/677) of the publications. DISCUSSION: Factors that favour publication of abstracts presented at the EFORT congress are oral presentation, experimental study, and a study with a higher level of evidence of I or II. It is common that a new author is added in the publication. Nevertheless, a high percentage of congress abstracts (58%; 947/1624) remains unpublished. LEVEL OF EVIDENCE: IV, retrospective study.

Biomechanical comparison of conventional versus modified technique in distal chevron osteotomies of the first metatarsal: A cadaver study.

BACKGROUND: Distal chevron osteotomy can be performed using a conventional or a modified technique. The aim of this biomechanical study was to compare the stability of the two techniques. METHODS: Eighteen first metatarsals from nine pairs of fresh frozen human cadaver feet were used. A distal chevron osteotomy was performed using the conventional technique in group 1 (n=9) and using the modified technique in group 2 (n=9). The head of the first metatarsals was loaded in two different configurations (cantilever and physiological), using a materials testing machine. RESULTS: In the cantilever configuration, the relative stiffness of the osteosynthesis in comparison with intact bone was 60% (±21%) in group 1 and 65% (±25%) in group 2 (p=0.61). In the physiological configuration, it was 47% (±29%) in group 1 and 47% (±21%) in group 2 (p=0.98). The failure strength in the cantilever configuration was 235N (±128N) in group 1 and 210N (±107N) in group 2 (p=0.47). CONCLUSIONS: The conventional and the modified technique for distal chevron osteotomy in the treatment of hallux valgus show a comparable biomechanical loading capacity in this cadaver study.

Biomechanical Comparison of Fixation With a Single Screw Versus Two Kirschner Wires in Distal Chevron Osteotomies of the First Metatarsal: A Cadaver Study.

Distal chevron osteotomy is a common procedure for surgical correction of hallux valgus. Osteosynthesis with 1 screw or 2 Kirschner wires has been commonly used. We compared the stability of the 2 techniques in distal chevron osteotomy. Sixteen first metatarsals from fresh-frozen human cadaver feet (9 different cadaveric specimens) were used. A standardized distal chevron osteotomy was performed. One first metatarsal from each pair was assigned to group 1 (3.5-mm cortical screw; n = 8) and one to group 2 (two 1.6-mm Kirschner wires; n = 8). Using a materials testing machine, the head of the first metatarsals was loaded in 2 different configurations (cantilever and physiologic) in succession. In the cantilever configuration, the relative stiffness of the osteosynthesis compared with intact bone was 59% ± 27% in group 1 and 68% ± 18% in group 2 (p = .50). In the physiologic configuration, it was 38% ± 25% in group 1 and 35% ± 7% in group 2 (p = .75). The failure strength in the cantilever configuration was 187 ± 105 N in group 1 and 259 ± 71 N in group 2 (p = .21). No statistically significant differences were found in stability between the 2 techniques. The use of 1 screw or 2 Kirschner wires had no significant differences in their biomechanical loading capacity for osteosynthesis in distal chevron osteotomies for treatment of hallux valgus.

Clinical and radiologic 2-4-year results of transforaminal lumbar interbody fusion in degenerative and isthmic spondylolisthesis grades 1 and 2.

STUDY DESIGN: Prospective clinical study. OBJECTIVE: To evaluate the clinical and radiographic result of the transforaminal lumbar interbody fusion (TLIF) as an alternative new technique in degenerative and isthmic lower grade spondylolisthesis. SUMMARY OF BACKGROUND DATA: TLIF is a new alternative surgical technique used for spinal fusion avoiding the ventral approach and can theoretically prevent typical complications, such as those seen in anterior and posterior lumbar interbody fusion. MATERIALS AND METHODS: There were 19 degenerative, 19 isthmic, and 1 dysplastic spondylolistheses operated on with TLIF. The clinical follow-up used the Oswestry Disability Index, the radiologic follow-up radiograph, analyzing segmental lordosis, intervertebral space, reduction, and fusion rate. The minimum follow-up was 24 months, mean clinical follow-up was 50 months, and radiologic follow-up was 35 months. RESULTS: The medium of the Oswestry Disability Index in all patients decreased from 23.5 to 13.5 points, in isthmic spondylolistheses from 20.5 to 10.95 after 2 years. The radiographic fusion rate was 94.8%. The sagittal translation was reduced from 23% to 15%. There were 3 (7.6%) serious postoperative complications observed, which required operative revision. CONCLUSIONS: TLIF is a safe and effective method to treat low-grade spondylolisthesis, which can theoretically prevent typical complications of anterior and posterior lumbar interbody fusion. The results of isthmic spondylolistheses were significantly better compared to degenerative spondylolistheses.