Internal Rotational Motion Research Articles

The effect of knee prosthesis design on tibiofemoral biomechanics during extension tasks following total knee arthroplasty

BackgroundDetermine whether the tibiofemoral motion and electromyographic activity of the knee differs in patients with a medial pivot implant, compared to those with cruciate-retaining and posterior-stabilised designs, during knee extension after Total Knee Arthroplasty (TKA). MethodsAn observational study was conducted on a cohort of patients that had undergone TKA for a minimum of 12 months prior. Three matched groups (n = 18) were categorised based on implant type: medial-pivot (MP), posterior-stabilised (PS) and cruciate-retaining (CR). Kinematics, with motion analysis (Vicon, USA) and surface electromyography (Delsys, USA) were assessed during step-ascent and walking tasks. ResultsAll groups displayed a similar amount of knee extension in both tasks. They also paradoxically produced an average mean internal rotation movement during knee extension in both the step-ascent and walking tasks. The only significant difference was found in the step-ascent task, in which the MP group produced a larger absolute amount of rotation than the CR implant group (P = 0.007), but neither group differed from the PS implant group. The groups did not differ in rotation during the walking task (P > 0.05). The MP group displayed significantly (P < 0.01) greater knee extensor activation during the step-ascent than the PS group. ConclusionThe MP design was only significantly different to another implant design for the step-ascent task. Patients with either knee implant types were not strictly limited to producing the traditional “screw-home” mechanism, defined by external rotation during extension. Furthermore, comparison with the non-implant contralateral limb suggested that rotation is not necessarily dictated by implant design.

The smallest proton-bound dimer H5+: theoretical progress.

The protonated hydrogen dimer, H5+, is the smallest system including proton transfer, and has been of long-standing interest since its first laboratory observation in 1962. H5+ and its isotopologues are the intermediate complexes in deuterium fractionation reactions, and are of central importance in molecular astrophysics. The recently recorded infrared spectra of both H5+ and D5+ reveal a rich vibrational dynamics of the cations, which presents a challenge for standard theoretical approaches. Although H5+ is a four-electron ion, which makes highly accurate electronic structure calculations tractable, the construction of ab initio-based potential energy and dipole moment surfaces has proved a hard task. In the same vein, the difficulties in treating the nuclear motion could also become cumbersome due to their high dimensionality, floppiness and/or symmetry. These systems are prototypical examples for studying large-amplitude motions, as they are highly delocalized, interconverting between equivalent minima through internal rotation and proton transfer motions requiring state-of-the-art treatments. Recent advances in the computational vibrational spectroscopy of the H5+ cation and its isotopologues are reported from full quantum spectral simulations, providing important information in a rigorous manner, and open perspectives for further future investigations. This article is part of a discussion meeting issue 'Advances in hydrogen molecular ions: H3+, H5+ and beyond'.

Improving Shoulder Internal Rotation Motion of In-season Throwing Athletes: A Randomized Controlled Trial

PURPOSE: Throwing athletes commonly experience loss of shoulder internal rotation (IR). This adaptation, when combined with compromised resting posture, has the potential to increase risk of rotator cuff and biceps tendinopathy, labral tears, and elbow injuries. This study investigated the effectiveness of two methods prescribed to restore IR: the Sleeper Stretch (SS), which aims to stretch the capsule, and the Balloon Blow (BB) which aims to optimize breathing, posture, and scapular stability. Because the BB is less stressful to the shoulder joint, it may be a superior alternative. We hypothesized that when using the BB, IR would be increased either as effectively, or more so, than the SS. METHODS: Healthy in-season baseball and softball players were randomly assigned an intervention (BB or SS) to the dominant arm 2x/day for 5 consecutive days. After a 2-week period of no intervention, both groups crossed over and performed the alternate intervention. IR was passively measured in supine at baseline, immediately after a throwing session on day 1, after intervention on day 1, and prior to practice on days 2-5. On the last day of the study, each subject was asked if he/she had a preference for either exercise. Statistical analysis for comparisons of differences in IR among intervention type (SS and BB) were performed using an analysis of covariance (ANCOVA) for the 6 instances as listed above. Statistical significance was set a priori at α≤0.05. RESULTS: 13 softball players (17.49 ± 0.63 yrs.; BMI 28.4±5.6) and 10baseball players (17.07 ±0.56 yrs.; BMI 24.6±4.7) participated in the study. Both interventions increased IR over the course of the 5 days, but there was no significant difference (p=0.66) between SS and BB. When performing SS, the mean IR was 45.7±11.38 degrees immediately after the throwing session and incrementally improved to 53.06±10.95 degrees on day 5. When performing BB, the similar incremental increase was from 47.39±12.15 degrees to 53.56±8.61 degrees. There was no statistically significant difference in preference between the SS (51.1%) and the BB (48.9%). CONCLUSIONS: The BB and the SS were both observed to be effective at increasing IR ROM in healthy in-season baseball and softball players over 5 days, yet neither proved to be superior with regard to degree of improvement nor speed of attaining increased IR.

Influence of friction on knee internal rotation in patients with knee arthroplasties during activities of daily living

Aims and Objectives: In recent decades, knee arthroplasty (KA) succeeded to improve patients’ clinical scores and gait patterns [1]. However, to date, studies primary focused on biomechanical analysis of level walking with total knee arthroplasty (TKA) patients. The investigation of neuromuscular more challenging activities of daily living (ADL) like stair climbing and especially ramp negotiation was partly neglected [2]. Furthermore, non-sagittal plane parameters have mostly not been considered, whereby the evaluation of e.g. transverse plane kinematics and kinetics may reveal potential differences between various endoprosthetic designs. Additionally, frictional forces transmit appreciable shear between the femoral component and the tibial polyethylene insert, potentially contributing to axial knee rotational constraints and implant loosening [3]. The aim of this study was to investigate transverse plane kinematics and kinetics in connection with the force of friction (FOF) during ADL in patients after TKA and unicondylar knee arthroplasty (UKA) surgery. Materials and Methods: - Motion analysis was performed using a ten-camera 3D- motion capture system (100 Hz, Vicon). - Ground reaction forces were measured utilizing in a total five force plates (1000 Hz, Kistler) - Kinematics and inverse dynamics were calculated with AnyBody Modeling SystemTM (AnyBody Technology). - FOF was estimated of the two articulating artificial surfaces (#CHR: mu_LOWER# =0.12) compared with the cartilage on cartilage friction (#CHR: mu_LOWER# =0.01). The Coulomb model of friction was applied to calculate FOF (Ff=Fn* #CHR: mu_LOWER#). - Completed ADL: level and decline walking, stair descent. - Participants: TKA (n=11), UKA (n=13), controls (CG, n=13). - Statistics: Statistical non-Parametric Mapping (SnPM). Results: No statistically significant differences were detected between the TKA and UKA group, regardless of the locomotion task. Each motor task revealed impaired knee internal rotation angles in the TKA group compared with the CG (Fig. 1, a-c). Fig. 1 (d) clarifies the determining role of the coefficient of friction regarding FOF which showed the highest values during stair ascent and decline walking in all groups. Interestingly, the mentioned tasks exposed lower knee internal moment time series compared with level walking. Lower internal rotation moments might contribute in connection with high friction to the constraint knee internal rotation motion, particularly during ADL including greater normal force values, such as stair climbing and ramp negotiation. Conclusion: Apart from implant congruency in the TKA group, FOF could represent a mechanical resistance, which contributes to the impaired knee motion in the transverse plane. References Smith A, et al., J Orthop Res. 22:260-266, 2004. Komnik I, et al., Gait Posture. 41:370-377, 2015. Wolterbeek N, et al., Gait Posture. 36:394-398, 2012

Detecting Ankle Instability With an Instrumented Ankle Arthrometer: An Experimental Study.

A new instrumented device was developed to quantify ankle joint stability during an anterior talar drawer test. The aim of the present study was to validate this device comparing bone kinematics with arthrometer measurement outcomes. An anterior talar drawer test was performed with 14 cadaver legs using a custom instrumented ankle arthrometer. Using clusters of bone-pin markers, the relative three-dimensional movement of calcaneus, talus, and fibula was simultaneously measured. Anterior drawer test was applied on the intact foot and after sequentially sectioning the anterior talofibular ligament, the calcaneofibular ligament, and the posterior talofibular ligament. Cutting the anterior talofibular ligament caused a significant increase in bone-pin measured anterior translations of calcaneus and talus as well as in the anterior translation of the arthrometer. Analysis of receiver operating characteristic curves indicates a fair to good ability to discriminate between the intact and the sectioned conditions with the arthrometer. Distal distraction, inversion, and internal rotation movements were observed when two and three ligaments were cut. Results revealed that the ankle arthrometer was sensitive to detect changes in bone-to-bone movements during an anterior talar drawer test, when the anterior talofibular ligament was sectioned. Presumably due to movements in additional planes of motion, the arthrometer was not able to differentiate between situations with one or more ligaments cut. In conclusion, the instrumented anterior talar drawer tester may augment current procedures in assessing ankle instability primarily caused by ruptures of the anterior talofibular ligament. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2019-2026, 2019.

Effect of the location of the split of the subscapularis on range of motion and stability of the glenohumeral joint following Latarjet or Trillat procedures

Aim:Compare the effect of Latarjet and Trillat procedures on glenohumeral stability and range of motion.Background:Little is known about the impact of the location of the sling effect on joint stability and range of motion.Methods:12 cadaveric shoulders were cleaned of soft tissue except for the subscapularis, conjoined tendon, and anterior capsule. A custom-made apparatus generating anterior humeral translation and joint compression was used. The machine applied compression load in the medial direction. The subscapularis and conjoint tendon were loaded. Internal/external range of motion and joint stability were assessed at 0°, 30° and 60° glenohumeral abduction. Range of motion was assessed by rotating the humeral shaft. Joint stability was assessed at maximum external rotation, translating the humerus. Specimen were tested in five conditions: 1) intact shoulder, 2) 6-mm bony glenoid defect (20% defect) 3) Trillat procedure, 4) Latarjet procedure with subscapularis split at the junction between its superior 2/3rds and inferior 1/3 rd, 5) Latarjet procedure with subscapularis split at the superior 1/3rds and inferior 2/3rds. Means were compared with a full factorial-repeated measures ANOVA with pairwise post hoc comparisons.Results:Peak translation force and stability ratio were significantly lower with the glenoid defect when compared to the intact and all the repaired conditions at all levels of glenohumeral abduction. The level of the subscapularis split had no significant influence on these values and no significant difference could be found between Trillat and Latarjet procedures. Range of motion in internal and external rotation were not significantly different between the different conditions.Conclusions:Joint stability and range of motion after a Latarjet are not impacted by the location of the subscapularis muscle split. Trillat and Latarjet techniques provide comparable stabilization of the joint, even in the presence of a critical bony defect of the glenoid.

Which one is the most limited movement in restricted shoulder joint

PurposeThe purpose of the study was to determine the most restrictive range of motion of the shoulder joint before treatment, as well as to examine which range of motion makes the treatment most difficult during physical therapy.MethodsOverall, 35 patients of a physical therapy and rehabilitation clinic who met the inclusion criteria were involved in the study. Active range of motion was measured and recorded by physiotherapists using a universal goniometer in standard positions. Functional range of motion was evaluated with the Constant-Murley Score (CMS) sub-parameters. The participants were given standard physical therapy routinely performed in the clinic, 3 sessions per week for 5 weeks. At the end of the treatment, the range of motion assessments were repeated.ResultsPre-treatment percentages were 43.24% for external rotation, 43.78% for internal rotation, 51.70% for abduction, 67.73% for flexion, 85.52% for extension. Post-treatment percentages were 62.50% for internal rotation, 72.54% for external rotation, 77.89% for abduction, 89.73% for flexion, 99.49% for extension. After treatment, the mean values of CMS subparameters were 9.71 ± 0.86 for flexion, 9.60 ± 0.95 for abduction, 8.57 ± 1.91 for external rotation, and 6.91 ± 2.13 for internal rotation. Pre- and post-treatment differences were observed to be statistically significant for the variables in the CMS (&lt;i&gt;p&lt;/i&gt; &lt; 0.05).ConclusionsThe study showed that early recovery of rotational movements, especially the internal rotation movement, at the beginning of the treatment positively affected the treatment process.

Relationship between Range of Motion of Shoulder Internal Rotation and Shoulder Posterior Laxity in Semiprofessional Baseball Pitchers

Relationship between Range of Motion of Shoulder Internal Rotation and Shoulder Posterior Laxity in Semiprofessional Baseball Pitchers

Total Shoulder Arthroplasty Using Intraoperative 3D Navigation.

Glenohumeral arthritis has become increasingly prevalent. For patients with glenohumeral arthritis and an intact rotator cuff, an anatomic total shoulder arthroplasty (TSA) has been shown to provide substantial pain relief with consistent, reproducible results. The primary indication is intractable pain that has not responded to nonoperative treatment, resulting in a substantial negative impact on the quality of life of the patient. Other indications for anatomic TSA include posttraumatic glenohumeral arthritis, inflammatory arthritis, and humeral head osteonecrosis. Contraindications include active infection, deltoid insufficiency, severe glenoid bone deficiency, and excessive glenohumeral posterior subluxation or laxity that cannot be surgically corrected. In order to provide the stability necessary to withstand the forces that impact the glenoid, the implant used in TSA should replicate the native anatomy of the individual patient by using a combination of implant modularity with different humeral neck angles and glenoid version augments, as well as dual eccentricity of the neck and head implant. The major steps in TSA include (1) preoperative planning, (2) patient positioning and setup, (3) surgical exposure, (4) accessing the glenohumeral joint, (5) preparation of the humerus, (6) exposure and preparation of the glenoid with component insertion, (7) humeral component insertion and trial reduction, (8) subscapularis reattachment and closure, and (9) postoperative immobilization and rehabilitation. The expected outcomes of TSA include improved quality of life (as indicated by improved outcome and patient satisfaction scores), shoulder active range of motion, and strength. In a large study examining outcomes of TSA in patients >55 years old, Patel et al.1 reported improved American Shoulder and Elbow Surgeons (48.3 ± 23.0), Constant (33.1 ± 16.7), and University of California Los Angeles (16.7 ± 6.3) shoulder scores, as well as improved active range of motion in active abduction (42° ± 41°), forward flexion (46° ± 40°), external rotation (33° ± 23°), and internal rotation (2.2° ± 1.8°) and decreased visual analog scale scores (-5.1 ± 2.9). Another study2 showed increased maximal weight improvement of 7.7 ± 4.0 lbs (3.5 ± 1.8 kg).

ACUTE EFFECTS OF MUSCLE ENERGY TECHNIQUE AND JOINT MOBILIZATION ON SHOULDER TIGHTNESS IN YOUTH THROWING ATHLETES: A RANDOMIZED CONTROLLED TRIAL

Posterior shoulder tightness (PST), defined as limited glenohumeral (GH) horizontal adduction and internal rotation motion, is a common occurrence in overhead athletes, particularly baseball and softball players, as a result of the extreme forces on the GH joint and the high number of throwing repetitions. Despite clinical evidence suggesting the use of joint mobilizations and muscle energy techniques (MET) for treating PST, there currently are no data examining the overall effectiveness of joint mobilizations and MET to determine optimal treatment for posterior shoulder tightness. To compare the acute effectiveness of MET and joint mobilizations for reducing posterior shoulder tightness, as measured by passive GH horizontal adduction and internal rotation ROM, among high school baseball and softball players. Randomized controlled study. Forty-two asymptomatic high school baseball and softball players were randomly assigned to one of three groups (14 MET, 14 joint mobilization, 14 control). Glenohumeral passive adduction and internal rotation ROM were measured in all participants in a pre-test post-test fashion. Between testing, the joint mobilization group received one application of GH posterior joint mobilizations. The MET group received one cycle of MET applied to the GH horizontal abductors. The control group received no intervention. Posttests measures were completed immediately following intervention or a similar amount of time resting for the control group and then again 15 minutes later. One-way analyses of covariance showed that the MET group had significantly more horizontal adduction ROM post-treatment compared to the control group (p = 0.04). No significant differences existed between groups in horizontal adduction (p > 0.16) or internal rotation (p>.28) or at the 15-minute posttests (p > 0.70). The results of this study indicate the application of MET to the horizontal abductors provides acute improvements to GH horizontal adduction ROM in high school baseball and softball players, while joint mobilizations provide no improvements. 1.

Compromised knee internal rotation in total knee arthroplasty patients during stair climbing.

Due to the significant role of rotational properties for normal knee function, this study aimed to investigate transverse plane kinematics and kinetics in total knee arthroplasty and unicondylar knee arthroplasty patients during activities of daily living compared to a healthy control group, including stair ascent and descent. The study participants consisted of a total knee arthroplasty group including posterior cruciate retaining and posterior stabilized designs as well as a unicondylar knee arthroplasty group and a healthy control group. Three-dimensional kinematics and kinetics were captured using a Vicon system and two Kistler force plates embedded in the floor and another two in a staircase. Inverse dynamics of the lower limbs was computed in Anybody™ Modeling System. Transverse plane joint angles and joint moments were analyzed utilizing the statistical non-parametric mapping approach, considering the entire curve shape for statistical analysis. The patients with total knee arthroplasty exhibited significantly reduced knee internal rotation of the operated knee compared to the control group and the patients’ unimpaired limb, especially during the stair climbing tasks. Both unicondylar and total knee arthroplasty patients were found to have similar reduced internal rotation motion time series in stair descent. In conclusion, potential kinematic and kinetic benefits of unicondylar knee arthroplasty over total knee arthroplasty could not be proven in the current study. Aside from the usually mentioned reasons inducing constrained knee internal rotation in total knee arthroplasty patients, future studies should investigate to what extent co-contraction may contribute to this functional impairment in patients after knee arthroplasty surgery.

Effects of the material of running shoes on biomechanical characteristics during running

Running as a sport is beneficial to the enhancement of cardiovascular function and body health. Running shoes play an assisting role during running. Running shoes which are made of different materials and have different sole rigidity can produce different counterforces to the sole of the foot and, moreover, have influences on running. In this study, running shoes with different rigidity of soles were manufactured using natural rubber and ehylene-vinyl acetate foaming composite material. The tracks of all the reflection points were captured using an infrared camera, and then the kinetic data of the subjects were recorded. The influence of the rigidity of sole on sport dynamics and biomechanics of lower limbs was analyzed and compared through kinetic test. The results demonstrated that the hardness of the sole had no influence on the first peak force, but had influence on the appearance time, maximum loading rate, and 50-ms passive impulse. When the hardness of the sole was 10°, the first peak force appeared the earliest, and the loading rate and passive impulse were the largest. The hardness of the sole had no influence on the motion of knee joints and abduction exercise of ankle joints, but had influence on the flexion and extension and internal rotation motion. When the hardness of the sole was 10°, the maximum flexion angle and internal rotation angle of the ankle joints were the largest.

Probing the methyl torsional barriers of the doubly substituted methyl-ethyl Criegee intermediate by FTMW spectroscopy

In a previous work, Cabezas et al., 2017 [21], we reported the rotational study of the doubly substituted methyl-ethyl Criegee intermediate, C2H5C(CH3)OO, by using Fourier transform microwave spectroscopy. Four different conformers were found showing A/E splittings due to the internal rotation of methyl tops. However for one of the conformers, syn2, some of the observed lines showed additional splitting that could not be assigned. The present work has been aimed to shed light on these transition line splittings of the syn2 conformer which are assigned to additional splittings coming from the two nonequivalent tops. As a consequence, 182 lines have been observed and the analysis of the internal rotation motions of two non-equivalent methyl tops enabled us to determine the barrier heights of the hindered methyl rotation of the two tops.

The effect of cup medialization and lateralization on hip range of motion in total hip arthroplasty

BackgroundThere is little description of the effect of cup position on the hip range of motion in total hip arthroplasty. The purpose is to evaluate the effect of cup medialization/lateralization with a compensatory increase/decrease in femoral offset on the hip range of motion, and whether the bone morphology of the anterior inferior iliac spine affects hip range of motion in total hip arthroplasty. MethodsUsing the CT data of 100 patients (male; 30, female; 70), 3D-dynamic motion analysis was performed in four scenarios with cup medialization/lateralization with the same/decreased global offset. We calculated the range of motion before component impingement and bony impingement in flexion, internal rotation and external rotation using the software. Furthermore, we measured bony morphological features of anterior inferior iliac spine, and we analyzed the correlations among them. FindingsWe found that the cup medialization with the same stem offset had negative effects on hip range of motion in flexion and internal rotation due to bony impingement, whereas cup medialization caused external rotation to significantly decrease with the same global offset. On the other hand, cup lateralization with the same global offset had negative effects on flexion and internal rotation, whereas external rotation increased. Furthermore, there were negative correlations among flexion and laterally large and steep anterior inferior iliac spine. InterpretationOur results demonstrated that the advantage of cup medialization can depend on the individual anatomy such as bony morphology of anterior inferior iliac spine in flexion.

Results of arthroscopic treatment of femroacetabular impingement (FAI)

IntroductionFemoroacetabular impingement (FAI) has been suggested as an important etiology of pain in the groin region in young adults especially athletes and there are theories connecting it to early onset osteoarthritis. AimTo assess the results of arthroscopic treatment of FAI. PatientsForty patients had been managed arthroscopically for their FAI in both El-Hadra university hospital and William Harvey Hospital. MethodsResults of arthroscopic treatment of FAI in 40 consecutive patients had been evaluated using patients reported outcomes (modified Harris Hip Score and international Hip Outcome Tool-12) and clinical measures of improvement of range of motion in both flexion and internal rotation in 90° of hip flexion. ResultsThe average of the outcome scores showed statistically significant improvement following the arthroscopic intervention. ConclusionFemroacetabular impingement is an important etiology of groin pain in young adults, nevertheless the athletes. Diagnosis of this condition is primarily a clinical one to be supported with relevant imaging. Hip arthroscopy is an effective approach to treat and correct the underlying bony abnormalities of FAI. Younger age of patients predicts better improvement in i-HOT-12 score.

Differentiation of bony and soft-tissue adaptations of the shoulder in professional baseball pitchers

Baseball pitching places tremendous forces on the arm, which may lead to structural tissue adaptations that are represented by changes in rotational range of motion (ROM). These adaptations often include both bony and soft tissue; however, the contribution of each tissue to the change in motion is not always clinically attainable. The purposes of this study were to determine the adaptations of ROM, bone, and soft tissue bilaterally and to examine the correlation between clinical ROM and humeral retroversion (HR)-corrected ROM. We hypothesized that glenohumeral internal rotation (IR) and total motion would be decreased and glenohumeral external rotation (ER), posterior capsule thickness (PCT), and HR would be increased in the dominant arm; that HR-corrected ROM would be significantly different than clinical ROM; and that HR-corrected ROM would be correlated with total motion difference. Thirty professional baseball pitchers participated in this study. HR, PCT, and glenohumeral IR and ER were evaluated in the dominant and nondominant shoulders of each subject. The dominant arm exhibited significantly more retroversion, ER, and PCT than the nondominant arm. The dominant arm also had significantly less IR and total motion than the nondominant arm. The total ROM difference was significantly correlated with both HR-corrected glenohumeral IR deficit and ER gain. HR-corrected glenohumeral IR deficit and ER gain may more accurately reflect the contribution of soft-tissue changes to ROM. Unfortunately, measurement of HR is not always clinically attainable, making clinical management difficult.

Remplissage Versus Modified Latarjet for Off-Track Hill-Sachs Lesions With Subcritical Glenoid Bone Loss

Background: Off-track Hill-Sachs lesions have been associated with high rates of recurrent shoulder instability. Both arthroscopic Bankart with remplissage and modified Latarjet have been described to treat off-track Hill-Sachs lesions. However, few comparative studies exist between the 2 techniques in heterogeneous populations. Hypothesis: Remplissage would have similar recurrence rates and clinical outcomes to modified Latarjet for off-track Hill-Sachs lesions with subcritical glenoid bone loss. Study Design: Cohort study; Level of evidence, 3. Methods: Between 2005 and 2015, 189 patients with recurrent anterior shoulder instability, off-track Hill-Sachs lesion, and less than 25% glenoid bone loss were identified. Arthroscopic Bankart with remplissage (group A) was performed in 98 patients, and modified Latarjet (group B) was performed in 91 patients. Surgeries were performed by multiple fellowship-trained surgeons at 2 centers. The mean follow-up time was 3.2 years. Patients were assessed for their risk of recurrence using the Instability Severity Index Score and had preoperative 3-dimensional imaging to assess humeral and glenoid bone loss, along with measurement of the glenoid track. Single Assessment Numeric Evaluation (SANE), Western Ontario Shoulder Instability Index (WOSI), visual analog scale (VAS) for pain, range of motion, recurrence rate, subsequent procedures, and complications were analyzed. Results: When comparing the remplissage and Latarjet groups, the remplissage group had a higher VAS pain score (2.2 vs 1.55, P = .041) and less internal rotation motion in abduction (40.9° vs 53.2°, P = .006). The complication rate was higher in the Latarjet group (12.1% vs 1%, P = .002). There was no difference between the 2 groups in patient-reported outcomes, such as WOSI and SANE. In addition, there was no difference between the 2 groups in revision rate and episodes of recurrent instability. In subgroup univariate analysis of revision patients, the remplissage group had higher VAS pain score (3.6 vs 2.2, P = .001), higher recurrence rate (34.8% vs 10.3%, P = .042), higher revision rate (43.5% vs 15.4%, P = .019), and lower complication rate (4.35% vs 28.2%, P = .024). For patients with >15% glenoid bone loss, Latarjet had lower recurrence rate (6.06% vs 28.6%, P = .034) and lower revision rate (3.03% vs 21.4%, P = .041). In collision and contact athletes, Latarjet had better WOSI scores (138 vs 231, P = .019) and lower recurrence rate (30% vs 0%, P = .005). In multivariate analysis, the odds of recurrence in the remplissage group were higher than in the Latarjet group in patients with previous instability surgery (3.56, P = .006), collision and contact athletes (2.37, P = .02), those with 10% to 15% glenoid bone loss (1.28, P = .04), and those with >15% glenoid bone loss (6.48, P = .001). Conclusion: For off-track Hill-Sachs lesions with subcritical glenoid bone loss, both the remplissage and modified Latarjet can achieve satisfactory results with the initial surgical intervention in the general population, but a higher complication rate was observed in the Latarjet group. However, Latarjet appears to be a better choice in patients with revision instability surgery, collision and contact athletes, and those with >10% glenoid bone loss.

Cross Body Stretching for Internal Rotation Deficit.

Posterior shoulder tightness and internal rotation deficit at the glenohumeral joint occur often in athletes who participate in throwing sports, racquet and crosse sports, or swimming (1–3). This tightness and decreased internal rotation motion may contribute to shoulder impingement pain through elevation of subacromial contact pressure at the greatest external rotation (4).This deficit can be corrected through passive and active stretching methods performed by a therapist or self-administered by the patient. Among the stretching techniques is the easy-to-perform cross body stretch (CBS). The newest systematically reviewed evidence indicates that the CBS immediately, and over the short-term, effectively reduces the rotation deficit and shoulder tightness compared to other common methods (2,5,6). The Figure demonstrates this stretching technique. The CBS is a fast-acting, low, or no-cost effective option to help treat glenohumeral internal rotation deficit.Figure: CBS: pull arm across the chest while creating tension in the muscles of the shoulder. Hold stretch for 10 to 15 s and repeat three times. Switch arms and repeat.

Optimizing reverse shoulder arthroplasty component position in the setting of advanced arthritis with posterior glenoid erosion: a computer-enhanced range of motion analysis

Our study purpose was to determine the optimal glenoid and humeral reverse shoulder arthroplasty (RSA) component design and position in osteoarthritic shoulders with severe glenoid retroversion deformities. Computed tomography scans from 10 subjects were analyzed with advanced software including RSA range of motion (ROM) analysis. Variables included glenoid component retroversion of 0°, 5°, 10°, 15°, and 20° and baseplate lateralization of 0, 5, and 10 mm. Humeral variables included 135°, 145°, and 155° angle of inclination (AOI) combined with variable humeral offset. Glenoid component lateralization had the greatest influence on ROM. In comparing each ROM direction among all lateralization options independently, there were significantly greater adduction, abduction, external rotation, extension, and flexion motions with progressively greater lateralization. Internal rotation motion was greater at 10 mm only. In analyzing the effects of glenoid version independently, no differences in adduction or abduction ROM were seen. With greater retroversion, decreased external rotation and extension motion was noted; however, greater internal rotation and flexion motion was seen with the exception of flexion at 10 mm of lateralization. For adduction, external rotation, and extension, a more valgus AOI resulted in less ROM at each progressively greater AOI independent of humeral lateralization. Internal rotation and flexion motions were greater with a more varus AOI but not significant between each inclination angle. Abduction ROM was maximized with a more valgus AOI. Humeral lateralization had no effect on ROM. In the setting of RSA for advanced glenoid osteoarthritic deformities, optimal ROM is achieved with 10-mm baseplate lateralization and neutral to 5° of retroversion mated to a humeral implant with a varus (135°) inclination angle.

Evaluation of distant sequelae of breast cancer treatment among patients after breast-conserving surgery depending on the type of intervention in the axillary fossa.

Aim of the studyThe goal of this work was to assess upper-limb sequelae among patients undergoing breast-conserving therapy (BCT) for breast cancer 5–6 years after the surgical procedure.Material and methodsA controlled clinical study was conducted on 128 patients who had undergone surgery 5–6 years prior. BCT + ALND (axillary lymph node dissection) was performed in 58 patients and 69 underwent BCT + SLND (sentinel lymph node dissection). Patients declared active participation in physiotherapy. The following parameters were assessed in studied subjects: range of motion in the shoulder joint, superficial sensation, upper limb circumference, skin sensation, and presence of winged scapula sign.ResultsFive to six years after BCT, patients who had undergone BCT + ALND presented with significantly poorer outcomes concerning upper limb range of motion on the operated side compared to the BCT + SLND group with regard to the following features: flexion (p = 0.00004), external rotation (p = 0.0292), and internal rotation (p = 0.0448). However, no statistically significant differences were noted between compared groups with regard to upper limb circumference and sensation disturbances. Statistically significant differences between limb on the operated side (operated limb – OL) vs. contralateral limb (healthy limb – HL) were noted in the BCT + SLND group with regard to the range of motion in extension (p = 0.0004), external rotation (p = 0.0055), and internal rotation (p < 0.0001), as well as the occurrence of winged scapula sign (p < 0.0001) and sensation disturbances (p < 0.0001).ConclusionsOur study demonstrated that both procedures are not free of distant sequelae, although the BCT + ALND group is more frequently affected.