In vivo evaluation of the kinematics of the long head of the biceps tendon within the pulley: A 3 T MRI motion analysis

Introduction

To evaluate the kinetic amplitude and direction of the long head of the biceps tendon (LHB) within the pulley and the proximal bicipital groove, we performed a 3T-magnetic resonance—throwing motion analysis.

Materials and methods

This prospective study was performed on a 3T-MRI scanner. A T2-weighted-3D sequence in three specific positions of throwing motion of the dominant shoulder was performed under isometric 5 N loading conditions or without loading, respectively. Measurements were performed in high (140°) abduction/external rotation, medium (110°) abduction/external rotation and low (45°) adduction-flexion/internal rotation. Multiplanar rotational reconstructions along the LHB in the bicipital groove allowed for the localization of the LHB including the degree of motion in the three most proximal slices.

Results

12 healthy volunteers (age 22–34 years) were enrolled. Adduction led to an anterior deviation of the LHB within the bicipital groove. Loading conditions in medium (110°) elevation/external rotation furthermore led to a significant anterior deviation of the LHB.

Conclusion

Our findings support the thesis that pulley lesions result from movements of the LHB especially in extreme positions during throwing/overhead activities. Load application in the medium (110°) elevation/external rotation position might enable a better evaluation of patients with dedicated pulley lesions. These results need further evaluation in larger study cohorts and in patients with dedicated rotator cuff lesions, which will be the focus of ongoing studies.     

Effect of reverse total shoulder arthroplasty humeral inclination on glenohumeral range of motion,deltoid force,and glenoid strain: a biomechanical study

BackgroundReverse total shoulder arthroplasty (RSA) primarily varies between 2 implant design options: a 135 humeral stem inclination that closely resembles anatomic orientation, versus the Grammont-style 155 humeral stem inclination that further medializes and distalizes the center of rotation (COR). The purpose of this study was to compare deltoid force, glenoid strain, and simulated glenohumeral range of motion (ROM) between RSA 135 and RSA 155 designs, with a series of standardized permutations of glenosphere offset and rotator cuff pathology.MethodsTwelve fresh-frozen cadaveric shoulder specimens were studied using a shoulder simulator. Native shoulder motion profiles for reproducible abduction range of motion were established using a customized testing device. Optical 3-dimensional tracking and pressure sensors were used to accurately record glenohumeral range of motion (ROM), deltoid force, and glenoid strain for RSA 135 and RSA 155 designs. For each cohort, all combinations of glenosphere offsets and rotator cuff tendon involvement were evaluated.ResultsThere was no significant difference in the overall abduction ROM between the 155 and the 135 humeral stem implants (P = .75). Resting abduction angle and maximum abduction angle were significantly greater with a 155 + STD (standard offset) construct than with a 135 + STD construct (P < .001 and P = .01, respectively). Both stem inclinations decreased combined deltoid force requirements as compared the native shoulder with a massive cuff tear. Effective glenoid strain did not vary significantly between 135 + STD and 155 + STD constructs (P = .66).ConclusionOverall, range of motion between the 135 and the 155 humeral stem inclinations was not significantly different. The cumulative deltoid force was lower in RSA shoulders when compared to native shoulders with massive rotator cuff tears, highlighting the utility of both implant designs. The Grammont-style 155 stem coupled with a 2.5 mm inferior offset glenosphere required less deltoid force to reach maximum abduction than did the more anatomic, lateralized 135 stem coupled with a 4 mm lateral offset glenosphere.Level of EvidenceBasic Science, Biomechanics Controlled Laboratory Study     

Flexions- und Extensionsosteotomien der proximalen Tibia

Background

Isolated deviations in flexion and extension of the leg axis are rare. These deviations can be corrected if necessary by osteotomy and the range of motion (ROM) of the knee joint can be optimized. In addition to correction in the frontal plane, the tibial slope (i.e. inclination of the surface of the tibial joint) can also be influenced by osteotomy and therefore osteotomy can also be utilized to optimize the biomechanical stability of the knee joint.

Method

Careful planning taking all three spatial planes and torsion into consideration is the foundation of a successful operation. A controlled surgical technique based on careful planning and some basic principles allows the alteration of the three dimensional alignment of the tibia.     

Thirty-Day Post-Discharge Outcomes Following COVID-19 Infection

BackgroundThe clinical course of COVID-19 includes multiple disease phases. Data describing post-hospital discharge outcomes may provide insight into disease course. Studies describing post-hospitalization outcomes of adults following COVID-19 infection are limited to electronic medical record review, which may underestimate the incidence of outcomes.ObjectiveTo determine 30-day post-hospitalization outcomes following COVID-19 infection.DesignRetrospective cohort studySettingQuaternary referral hospital and community hospital in New York City.ParticipantsCOVID-19 infected patients discharged alive from the emergency department (ED) or hospital between March 3 and May 15, 2020.MeasurementOutcomes included return to an ED, re-hospitalization, and mortality within 30 days of hospital discharge.ResultsThirty-day follow-up data were successfully collected on 94.6% of eligible patients. Among 1344 patients, 16.5% returned to an ED, 9.8% were re-hospitalized, and 2.4% died. Among patients who returned to the ED, 50.0% (108/216) went to a different hospital from the hospital of the index presentation, and 61.1% (132/216) of those who returned were re-hospitalized. In Cox models adjusted for variables selected using the lasso method, age (HR 1.01 per year [95% CI 1.00–1.02]), diabetes (1.54 [1.06–2.23]), and the need for inpatient dialysis (3.78 [2.23–6.43]) during the index presentation were independently associated with a higher re-hospitalization rate. Older age (HR 1.08 [1.05–1.11]) and Asian race (2.89 [1.27–6.61]) were significantly associated with mortality.ConclusionsAmong patients discharged alive following their index presentation for COVID-19, risk for returning to a hospital within 30 days of discharge was substantial. These patients merit close post-discharge follow-up to optimize outcomes.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-021-06924-0.KEY WORDS: COVID-19, mortality, re-admission, discharge     

Reverse LISS plating for intertrochanteric Hip Fractures in elderly patients

Background  

Fractures of the intertrochanteric hip are common and the treatment of unstable fractures generally requires an operative approach. In elderly patients, osteoporosis makes internal fixation problematic and frequently contributes to failed fixation and poor clinical results. We have attempted to apply the Less Invasive Stabilization System (LISS) in reverse position for the repair of intertrochanteric hip fractures in elderly patients with osteoporotic bones. A retrospective review is presented of the cases of 28 elderly patients with stable and unstable fractures of the intertrochanteric hip treated using the reverse LISS.     

Die kindliche Patellaluxation

Traumatic and non-traumatic patellofemoral instability (PFI) in children and adolescents is a complex problem determined by a large number of mechanical and pathomorphological factors which are most important in non-traumatic dislocations. While conservative treatment with a short period of immobilization followed by early passive motion and isometric quadriceps strengthening can be considered for traumatic dislocations without cartilaginous injury, a surgical intervention should be considered in cases of non-traumatic origin. As 90% of cases of PFI are non-traumatic and correlated with skeletal deformities, the rate of recurrent dislocation is reported to be up to 80% after initial conservative treatment. To optimize the clinical results the pathologies causing PFI have to be urgently diagnosed. In addition to skeletal pathomorphologies further risk factors have to be taken into consideration for determining the optimal time for surgery. In the past an unreasonably high number of operative techniques for stabilization were described with not always successful clinical results, however more recent biomechanical and clinical studies have shown that a manageable number of operations is sufficient to stabilize the patella. Refixation and the minimally invasive double-bundle technique for reconstruction of the medial patellofemoral ligament are the main surgical techniques to treat PFI in children as both can be used even when the epiphysial cartilage is still open. Further surgical interventions to correct bone deformities, such as trochleoplasty or osteotomy addressing lower limb deformities should be performed after closure of the epiphysial cartilage, while displacement of the tibial tuberosity and soft tissue interventions have to be seen more critically.     

Skeletal maturation during thyroxine treatment in children with congenital hypothyroidism

Heyerdahl S, Kase BF, Stake G. Skeletal maturation during thyroxine treatment in children with congenital hypothyroidism. Acta Prediatr 1994;83:618–22. Stockholm. ISSN 0803–5253
The aim of this investigation was to study if bone age development (assessed by the Greulich & Pyle atlas) was related to L-thyroxine treatment in 47 children with congenital hypothyroidism, treated early and according to general recommendations. In spite of frequent delay in skeletal maturation at diagnosis, the delay in mean bone age at a mean chronological age of 1.5 years was slight (0.5 months), and 30% of the variation in bone age SD score (SDS) at 1.5 years was accounted for by the dose of L-thyroxine and serum thyroxine during the first year. The children with a bone age within ± 1 SDS had a prescribed mean dose of L-thyroxine per kg body weight from 3 to 12 months of age of 5.4 ± 1.7 pg/kg/day, and their mean serum thyroxine concentration during the first year was 175 ± 29 nmol/l. We conclude that bone age at 1.5 years of age was positively correlated with the dose of L-thyroxine and the serum thyroxine concentration during the first year. This supports the general use of bone age assessments as a complement to other treatment variables in the follow-up of children with congenital hypothyroidism.