Research productivity during orthopedic surgery residency correlates with pre‑planned and protected research time: a survey of German‑speaking countries

Purpose The purpose of this study was to identify modifiable factors associated with research activity among residents working in orthopedic surgery and traumatology. Methods Residents at 796 university-affiliated hospitals in Austria, Germany, and Switzerland were invited to participate. The online survey consisted of questions that ascertained 13 modifiable and 17 non-modifiable factors associated with the residents’ current research activities. Responses of 129 residents were analyzed. Univariate linear regression was used to determine the association of individual factors with the current research activity (hours per week). The impact of significant non-modifiable factors (with unadjusted p values < 0.05) was controlled for using multivariate linear regression. Results The univariate analysis demonstrated six non-modifiable factors that were significantly associated with the current research activity: a University hospital setting (p < 0.001), an A-level hospital setting (p = 0.024), Swiss residents (p = 0.0012), the completion of a dedicated research year (p = 0.007), female gender (p = 0.016), and the department’s size (p = 0.048). Multivariate regression demonstrated that the number of protected research days per year (p < 0.029) and the percentage of protected days, that were known 1 week before (p < 0.001) or the day before (p < 0.001), were significantly associated with a higher research activity. Conclusions As hypothesized, more frequent and predictable protected research days were associated with higher research activity among residents in orthopedic surgery and traumatology. Level of evidence III

Radiological changes do not influence clinical mid-term outcome in stemless humeral head replacements with hollow screw fixation: a prospective radiological and clinical evaluation

Abstract Background Stemless shoulder arthroplasty is a fairly new concept. Clinical and radiological follow-up is essential to prove implant safety and concept. This prospective single-centre study was performed to evaluate the influence of radiological changes on clinical mid-term outcome following stemless humeral head replacement with hollow screw fixation. Methods Short- and mid-term radiological and clinical evaluations were performed in 73 consecutive shoulders treated mainly for idiopathic and posttraumatic osteoarthritis with stemless humeral head arthroplasty including 40 hemi- (HSA) and 33 total shoulder arthroplasties (TSA). Operating times of stemless implantations were compared to 110 stemmed anatomical shoulder prostheses. Appearances of humeral radiolucencies or radiological signs of osteolysis or stress shielding were assessed on standardized radiographs. Patients’ clinical outcome was evaluated using the Constant score and patients’ satisfaction was documented. Results Radiological changes, detected in 37.0%, did not affect clinical outcome. Constant scores significantly improved from baseline to short and mid-term follow-up (p < 0.001). The majority of patients (96.2%) were satisfied with the procedure. No loosening of the humeral head component was detected during a mean follow-up of 58 months. Operating times were significantly shorter with stemless compared to stemmed implants (p < 0.001). Conclusions Clinical mid-term outcome after stemless humeral head replacement was not affected by radiological changes. Trial registration The institutional review board (St. Vincent Hospital Vienna; 201212_EK01; date of issue: 11.12.2012) approved the study. The trial was registered at ClinicalTrials.gov ( NCT02754024 ). Retrospective registration

Biomechanical evaluation of an arthroscopic transosseous repair as a revision option for failed rotator cuff surgery

Abstract Background The number of revision rotator cuff cases is increasing. The literature is lacking guidance or biomechanical evaluation for fixation strength in a revision case scenario. Therefore, the aim of the study was to provide biomechanical data investigating primary fixation strength of a transosseous technique after anchor pullout failure of a single row reconstruction. It was hypothesized that an arthroscopic transosseous repair system as a procedure for rotator cuff revisions is providing equivalent stability compared to a primary single row suture anchor fixation due to change of fixation site. Methods Eight matched pairs (n = 16) of fresh frozen human shoulders were tested. The paired specimen shoulders were randomly divided into two repair groups (A single row and B primary transosseous repair). The potted specimens were mounted onto the Servohydraulic test system. Both groups were tested under cyclic loading followed by load to failure testing. Suture anchor repair shoulders (group A) that were tested to failure underwent a revision transosseous repair and were subsequently tested again using the same setup and protocol (group C). Results The mean native footprint areas did not show a significant difference between groups. The reconstructed footprint area showed a significantly greater coverage in favor of the transosseous repair. Ultimate load to failure of reconstructions with the primary anchor fixation (344.73 N ± 63.19) and the primary transosseous device (375.36 N ± 70.27) was not significantly higher compared to the revision repair (332.19 N ± 119.01 p = 0.45, p = 0.53). Conclusion The tested transosseous anchor device is a suitable option to widely used suture anchors, providing equivalent fixation properties even in a revision case scenario. Level of evidence Basic Science Study, Biomechanics

Bone-on-Bone Anatomic Patellar Tendon Graft Anterior Cruciate Ligament Reconstruction: A Reproducible Technique Combining Press-Fit and Extracortical Fixation

Scientific interest in optimizing outcomes after anterior cruciate ligament (ACL) reconstruction is ongoing, and some recent developments have focused on graft shape as one of the most important factors of anatomic graft placement. The double-bundle or fanlike structure of the native ACL seems to more closely restore normal function and control of rotational stability of the knee with implant-free or press-fit techniques, creating a favorable situation in terms of direct graft-tunnel healing. The ACL reconstruction technique presented in this article enables safe, reproducible, and anatomic fixation of the patellar tendon autograft, providing the biological and biomechanical benefits of direct bony integration of the ribbonlike bone–patellar tendon–bone graft. Because press-fit fixation represents a technically challenging surgical procedure, the goal of the described technique is to enable direct bone-to-bone healing by using secondary extracortical femoral and tibial fixation without the need for a true press-fit situation. Safe and anatomic femoral tunnel drilling is achieved with an outside-in technique (retrograde drilling), hence providing advantages in the routine clinical setting in terms of applicability and time effort. To reduce donor-site morbidity caused by bone block harvesting, refilling of the harvest sites with autologous material is performed

An Arthroscopic Knotless Technique for Anatomical Restoration of the Rotator Cuff and Superior Capsule: The Double-Layer Cinch Bridge

Rotator cuff repairs are the most common procedures in shoulder surgery, but still show long-term retear rates of up to 70%. Nonanatomic reconstruction is one possible cause of repair failure. The rotator cuff histologically consists of 5 separate layers of which 2 are macroscopically identifiable: the superior or tendinous layer and the inferior or capsule-ligamentous layer. In case of rotator cuff tears, these layers are often retracted to different degrees. The intraoperative detectable prevalence of rotator cuff delamination reaches up to 85%. Anatomical rotator cuff repair, which also includes restoration of the layered structure, could re-establish native tendon morphology and thus potentially decreases retear rates. The use of a knotless construct to avoid cuff strangulation and maintaining tendon perfusion could further decrease the risk of repair failure. Double-layer reconstructions are challenging and time consuming because each layer needs to be penetrated separately. Only few studies reported about double-layer reconstruction of the posterosuperior rotator cuff. This Technical Note is the first to present an arthroscopic knotless transosseous-equivalent double-layer repair technique

Critical shoulder angle combined with age predict five shoulder pathologies: a retrospective analysis of 1000 cases

Abstract Background Acromial morphology has previously been defined as a risk factor for some shoulder pathologies. Yet, study results are inconclusive and not all major shoulder diseases have been sufficiently investigated. Thus, the aim of the present study was to analyze predictive value of three radiological parameters including the critical shoulder angle, acromion index, and lateral acromion angle in relationship to symptomatic patients with either cuff tear arthropathy, glenohumeral osteoarthritis, rotator cuff tear, impingement, and tendinitis calcarea. Methods A total of 1000 patients’ standardized true-anteroposterior radiographs were retrospectively assessed. Receiver-operating curve analyses and multinomial logistic regression were used to examine the association between shoulder pathologies and acromion morphology. The prediction model was derived from a development cohort and applied to a validation cohort. Prediction model’s performance was statistically evaluated. Results The majority of radiological measurements were significantly different between shoulder pathologies, but the critical shoulder angle was an overall better parameter to predict and distinguish between the different pathologies than the acromion index or lateral acromion angle. Typical critical shoulder angle-age patterns for the different shoulder pathologies could be detected. Patients diagnosed with rotator cuff tears had the highest, whereas patients with osteoarthritis had the lowest critical shoulder angle. The youngest patients were in the tendinitis calcarea and the oldest in the cuff tear arthropathy group. Conclusions The present study showed that critical shoulder angle and age, two easily assessable variables, adequately predict different shoulder pathologies in patients with shoulder complaints

Allo- and autografts show comparable outcomes in chronic acromioclavicular joint reconstruction: a systematic review

Purpose The aim of this review was to compare clinical and radiological outcome of acromio-clavicular joint reconstruction with allografts versus autografts. Methods The PubMed, MEDLINE, The Cochrane Library and WEB OF SCIENCE databases were searched in accordance with the PRISMA guidelines until February 2020 using the terms: 'coracoclavicular' OR 'coraco-clavicular' OR 'acromioclavicular' OR 'acromio-clavicular joint', AND 'reconstruction'. All studies reporting on clinical and radiological outcome as well as complications after ACJ reconstruction using allo- and/or autografts were included. Results A total of 29 articles, including 2 prospective and 27 retrospective studies, involving 622 patients, reconstructed with either allo- (n = 360) or auto-grafts (n = 262), for acromio-clavicular joint instability were identified and included in this review. The majority of studies had low sample sizes (66.7% below n = 20), were retrospective (93.3%), with short-term follow-ups (average 26.2 +/- 12.6 months; range 6-186). The study with the largest sample size (n = 128) did not report clinical outcome. A comparison between allo- and auto-graft showed no significant differences regarding age, gender, and follow-up times. Clinical outcome was comparable in both groups, loss of reduction (LOR) and complication rates were higher in the allograft group. Overall a reduction of LOR was shown if additional horizontal stabilization was performed. Also a higher LOR and revision rate was documented in allografts without suture or suture-tape augmentation. The use of more clavicular drill-holes correlated with a higher frequency of fracture. Conclusions A systematic review of the available peer-reviewed literature addressing allograft and autograft reconstruction of unstable coracoclavicular ligaments shows that the published studies are generally of low quality with low levels of evidence. The published literature shows no significant difference in clinical outcomes between the use of autografts or allografts in ACJ reconstruction surgery. Surgical techniques utilizing additional horizontal stabilization may contribute to lower rates of LOR. In cases where allograft tissue is used for ACJ reconstruction the use of suture/tape augmentation may reduce LOR rates as well as revision rates

Footprint coverage comparison between knotted and knotless techniques in a single-row rotator cuff repair: biomechanical analysis

Abstract Background The objective of this biomechanical study is to compare two variations of single-row knotless techniques (Knotless repair and Rip-stop Knotless repair) against a single-row double-loaded anchor (DL) repair, focused on evaluating contact pressure and contact area amongst three different single-row techniques for rotator cuff repairs. Methods A total of 24 fresh frozen human shoulders were tested. Specimens were randomly assigned into one of the three single-row (SR) repair groups: A Knotted single-row double-loaded anchor (DL) repair, a Knotless (K) repair, or a Knotless Rip-Stop (KRS) repair. The footprint was measured after complete detachment of the supraspinatus tendon from the greater tuberosity, introducing pressure sensors between bony footprint and detached rotator cuff, and finally reconstructing it. All specimens were mounted onto a servohydraulic test system to analyze contact variables at 0° and 30° of abduction with 0 N, 30 N and 50 N of tension. Results Groups did not differ significantly in their footprint sizes: DL group 359.75 ± 58.37 mm2, K group 386.5 ± 102.13 mm2, KRS group 415.87 ± 93.80 mm2 (p = 0.84); nor in bone mineral density: DL group 0.25 ± 0.14 g/cm2, K group 0.32 ± 0.19 g/cm2, KRS group 0.32 ± 0.13 g/cm2, (p = 0.75) or average age. The highest mean pressurized contact area measured for the K repair was 248.1 ± 50.9 mm2, which equals a reconstruction of 67.1 ± 19.3% at 0° abduction and a 50 N supraspinatus load. This reconstructed area was significantly greater compared with the DL repair 152.8 ± 73.1 mm2, reconstructing 42.0 ± 18.5% on average when under the same conditions (p = 0.04). The mean contact pressure did not significantly differ amongst groups (p = 1.0): DL group 30.8 ± 17.4 psi, K group 30.9 ± 17.4 psi and KRS group 30.0 ± 10.9 psi. Neither the 30° abduction angle nor the supraspinatus load had a significant influence on the contact pressure in our study. Conclusion Both single-row knotless techniques resulted in significantly higher footprint reconstruction, providing larger contact area and a more uniform pressure distribution when compared with the single-row Knotted techniques. The mean contact pressure did not differ among groups significantly. These knotless techniques may be an alternative if the surgeon decides to perform a single-row rotator cuff repair. Level of evidence Basic Science Study, Biomechanics