Rotation Range Of Motion Research Articles

Biomechanical evaluation of a hybrid suture and anchor-based hip capsular repair

BackgroundHip capsulotomies, performed routinely during hip arthroscopy, can contribute to adverse joint kinematics. Direct repair is not always feasible. Therefore, the aim of this study was to evaluate the biomechanics of a conventional all-suture repair versus a hybrid suture and anchor-based capsular repair. MethodsNine paired (n = 18) hips were tested on a joint-motion simulator, utilizing optical trackers to capture kinematic data. Pairs were randomly allocated to capsular repair type and tested as (1) intact, (2) after T-capsulotomy, and (3) repair each at 0°, 45°, and 90° flexion. Internal and external rotation torques and abduction/adduction torques of 3 N·m were applied and rotational range of motion and joint translations recorded. FindingsAt 0°, following repair there were no significant differences in joint rotation or translations between repairs (p > 0.134).At 45°, both repair types restored motion to near intact values, with no significant differences between groups. Similarly, there were no significant differences in joint translations between repairs.At 90°, both types of capsular repair failed to restore rotational range of motion, with persistent increases in motion (47.0 ± 16.7°) compared to the intact condition (44.1 ± 15.8°, p = 0.006); however, there were no significant differences between repair groups. There were no significant differences in joint translations between repairs. InterpretationUse of a hybrid repair produced comparable joint rotation and translation under all testing conditions as an all-suture repair. As such, this technique represents a viable option for capsular repair where proximal capsular tissue is deficient.

The relationship between trunk rotation and shot speed when performing ice hockey wrist shots

ABSTRACT There has been minimal work examining kinematics of ice hockey wrist shots. The objective was to determine if puck and blade speed were related to trunk rotation during wrist shots in elite and recreational players. Elite (n = 10) and recreational (n = 10) ice hockey players completed wrist shots while skating and from a stationary position on real ice. A 14 camera motion capture system collected kinematic data for the trunk, pelvis, stick, and puck. Dependent variables included peak puck and blade speeds. Independent variables included peak trunk rotation angles, trunk rotation range of motion (ROM), and group (elite vs. recreational). Hierarchical linear models compared relationships between dependent and independent variables for both skating and stationary wrist shots. Greater peak trunk rotation away from the net was related (p < 0.05) to faster puck and blade speeds for skating and stationary wrist shots. This relationship was stronger in the recreational group for skating wrist shots (p < 0.01). Greater trunk rotation ROM was related (p = 0.01) to faster puck and blade speeds for the skating wrist shots only. Coaches should encourage players to increase trunk rotation away from the net during wrist shots, especially in recreational players.

Range of motion following percutaneous fixation of pediatric supracondylar humerus fracture is independent of anterior osseous fragment resorption.

The objective of this study was to understand postoperative resorption of the anterior osseous fragment following closed reduction and percutaneous pinning (CRPP) of pediatric supracondylar humerus fractures and its effect on final range of motion (ROM). Eighty-six patients that underwent CRPP had sagittal and or axial plane deformities resulting in an anterior fragment. Humerocapitellar angle (HCA), anterior humeral line (AHL) and angle of rotation (AoR) were measured. A total of 11 (12.8%) patients failed to resorb the anterior fragment, 10 (90.9%) had satisfactory ROM. HCA initially was acceptable in 40 (46.5%) patients, and 37 (92.5%) demonstrated acceptable ROM. Final HCA was acceptable in 44 (51.2%) patients and 42 (95.4%) had acceptable final ROM. AHL was in the anterior third of the capitellum in 35 (40.6%) patients and 33 (94.3%) had acceptable ROM. Final AHL was in the anterior third of the capitellum in 43 (50.0%) patients and 41 (95.3%) had acceptable final ROM. No difference was found between acceptable ROM and HCA or AHL at either follow-up. Sixty-five and 21 patients had an AoR of 0° and between 23 and 36°, respectively. A total of 59 (90.7%) patients with an AoR of 0°, and 18 (85.7%) patients with an AoR of 23-36° displayed acceptable ROM. A total of 57 (87.7%) patients with an AoR of 0° and 18 (85.7%) with an AoR of 23-36° resorbed the anterior fragment. No association was found between rotational deformity and postoperative ROM or fragment resorption. Postoperative sagittal and axial plane alignment, HCA, AHL, AoR and resorption of the anterior osseous fragment does not correlate with final ROM.

Trigger Point Release versus Instrument Assisted Soft Tissue Mobilization on Upper Trapezius Trigger Points in Mechanical Neck Pain: A Randomized Clinical Trial

Abstract Background: Mechanical neck pain is a widespread sig-nificant health problem with a huge burden on the individual and economy. Finding a noninvasive effective treatment that's non exhaustive for the therapist and non painful for the patient is highly needed. Aim of Study: This study investigated and compared the effects of instrument assisted soft tissue mobilization (IASTM) using m2t blade and trigger point release (TPR) in terms of neck lateral flexion and rotation range of motion on upper trapezius (UT) myofascial trigger points (MTrPs) in mechanical neck pain. Methods: Forty patients between 18 and 55 years were randomized to one either group A or B. Group A received one session of TPR and passive stretching while group B received one session of IASTM using M2t blade and passive stretching. Tape measurement was used to evaluate patients pretreatment, post treatment and at follow-up. Results: Within group analysis, there was a significant increase in neck lateral flexion and rotation at immediate post treatment and at follow-up in both groups (p 0.05) Conclusion: IASTM using M2t blade and TPR were effective in treating patients with mechanical neck pain and UT MTrPs.

DESCRIPTIVE PROFILE OF SHOULDER RANGE OF MOTION AND STRENGTH IN YOUTH ATHLETES PARTICIPATING IN OVERHEAD SPORTS.

The unilateral and repetitive nature of overhead sports, often result in a biomechanical overload of the upper extremity. Understanding the musculoskeletal shoulder range of motion (ROM) and strength patterns in the youth sports of baseball, softball, and tennis could assist injury prevention screening and further the development of conditioning and rehabilitation programs. To generate a descriptive profile of shoulder musculoskeletal characteristics and determine whether bilateral differences in shoulder ROM exist in youth baseball, softball, and tennis athletes. A secondary aim was to determine whether shoulder rotational adaptations are correlated with playing position, sport, or years of experience. Descriptive Laboratory. A total of 136 competitive youth overhead athletes (baseball: n = 51,12.8 ± 0.9yrs; softball: n = 63,12.3 ± 1.1yrs; and tennis: n = 22,12.5 ± 0.9yrs) participated. Bilateral shoulder internal (IR) and external (ER) passive ROM and external rotation strength were measured using an inclinometer and handheld dynamometer. Significant differences (p<.001) in bilateral shoulder ROM and ER strength were found between the athletes in the three sports. Post-hoc test revealed tennis athletes had greater bilateral shoulder ROM than both baseball and softball athletes, but baseball and softball athletes had greater bilateral ER strength than tennis athletes. There were no differences between baseball and softball athletes. Additionally, tennis athletes had greater bilateral internal rotation and total ROM but less ER strength than baseball pitchers, baseball positional athletes, softball pitchers, and softball positional athletes. There were no significant differences between positions and baseball and softball athletes. There were no significant correlations between playing position, sport, or years of experience. The results of this study showed differences in shoulder passive ROM and strength adaptations between youth tennis, baseball, and softball athletes. The descriptive nature of this study is impactful as it presents specific ROM adaptions seen in this population. Future research is needed to further evaluate if the "at risk" ROM identified in older populations holds true in the youth population. Diagnosis, Level 3b.

Computer tomography assessment of the subscapularis after reverse shoulder arthroplasty and subscapularis repair: reduction in subscapularis size do not affect clinical outcomes

BackgroundExcellent Clinical and patient-reported outcome have been reported following Reverse Shoulder Arthroplasty (RTSA). However, outcomes in range of motion (ROM) remain variable. The role and importance of subscapularis repair during RTSA is a topic of intense debate and the long term-integrity of the subscapularis after repair remains poorly studied. Aims of this study were to radiologically evaluate pre- and postoperative condition of the subscapularis muscle in RTSA with concurrent subscapularis tendon repair using transosseous suture, and to investigate the correlation between clinical and radiological results. MethodsPatients who had undergone RTSA with subscapularis repair in our Institute between January 2010 and November 2016 were included. Constant, UCLA, Simple Shoulder Test and Visual Analog Scale (VAS) pain questionnaires were administered pre- and postoperatively. Internal rotation ability was recorded on a 6-point scale. Pre - and postoperatively shoulder CT scans were performed by a blinded examiner from which subscapularis muscle cross-sectional area (SMCSA) and supraspinatus fossa cross-sectional area (SFCSA) were measured in square millimeters. The SMCSA/SFCSA ratio was employed to standardize values for individual anatomical differences between patients. ResultsThe study included 32 patients (32 shoulders). Mean follow-up was 74.6 months ± 15.2 months (range 35–117 months). Statistically significant differences were found between pre- and postoperative VAS score, Constant Score, UCLA and Simple Shoulder Test scales (P < .0001). A postoperative SMCSA reduction of >35% was found in 38% of patients. Only 21% of patients maintained their preoperative SMCSA/SFCSA ratio. Overall, a statistically significant difference in pre and postoperative SMCSA/SFCSA ratios was found (P < .001). A correlation between radiological findings and clinical outcomes was not found. ConclusionPostoperative subscapularis size expressed as SMCSA and SMCSA/SFCSA ratio, was significantly reduced in the majority of patients treated with non-lateralized RTSA design and concurrent subscapularis tendon repair at final follow-up. A correlation between radiological findings and clinical outcomes was not found. RTSA with subscapularis tendon repair provides a high degree of patient satisfaction, as well as statistically significant improvements in clinical outcomes and internal rotation ROM. Being associated with several advantages, subscapularis repair may be routinely recommended. Level of evidenceLevel II; Prospective Cohort Design; Prognosis Study

The effect of distal radius fractures involving the distal radioulnar articular joint on forearm rotation

BackgroundThe objective of this study was to predict the function of the forearm rotation on the basis of the articular surface of the sigmoid notch from three-dimensional reconstruction images.MethodsWe retrospectively reviewed patients who underwent volar plate fixation for intra-articular distal radius fractures (DRFs) in our institution between January 2017 and July 2019. The 3D image of the sigmoid notch on the fractured distal radius was reconstructed and looked up from the ulnar view to determine the existence of gaps or steps. Patients with or without gaps/steps on the sigmoid notch were included in the case group or control group, respectively. The patients’ basic data and postoperative data were collected and compared.ResultsA total of 81 patients were included. There were 33 patients in the case group, and 48 patients in the control group. There was no significant difference between the two groups at baseline. The total range of motion (ROM) of rotation in the case group and control group was 130.3 ± 6.2° and 145.3 ± 6.7°, respectively (P < 0.001). The percentage of rotation ROM of contralateral limb in the case group and control group was 72.3 ± 3.1% and 80.7 ± 3.6%, respectively (P < 0.001). VAS during forearm rotation was 2.1 ± 0.7 in the case group, which is significantly higher than that in the control group (1.5 ± 0.5, P < 0.001).ConclusionThis study proposed a new method to assess the articular surface of the sigmoid notch which is based on 3D reconstruction images. With the assistance of this method, we found that gaps or steps on the sigmoid notch not only limit forearm pronation rotation and supination rotation, but also cause apparent wrist pain during forearm rotation movement and poor wrist ability.

The science of biomechanics can promote dancers’ injury prevention strategies

Background The most common sports activities leading to menisci injuries are tennis, jogging, gymnastics, and dancing. Menisci injuries in dancers most frequently occur due to rotational forces applied to the knee. Objectives: Since dancers’ movement is of great biomechanical and rehabilitation interest, the purpose of this review is to explore the biomechanical approach of this issue as well as to identify any gap to this process and propose corresponding assessments. A literature review search database of Pubmed, Medline, EMBASE, AMED, Scopus, Google Scholar, and CINAHL was conducted using relevant keywords and phrases. Major Findings: The most common dance movement that can cause meniscus injury, is the grand plié, because of the excessive range of motion combined to compressive forces and axial rotations that occur during the execution of the movement. Conclusions Α complete three-dimensional kinematic assessment of the lower limb joints from dynamic grand pliés or in intermidiate positions of the legs has not been made. Thus, further research has to be done with the use of optoelectronic cameras and force plates, to accurately identify weather excessive knee rotation range of motion or moments could lead in medial or/and lateral meniscus tear during the grand plié.

A Model Used to Consider Lower Extremity Range of Motion to Identify Fall Experience in Community-Dwelling Older Women: A Retrospective Study

Background: Reduced lower extremity range of motion (ROM) with aging is related to the frequency of falls in older adults. Therefore, this study developed and assessed a model that considers lower extremity ROM in identifying the frequency of fall in community-dwelling older women. Methods: Seventy-eight community-dwelling older women (mean age ± SD, 70.4 ± 4.6 years; age range, 65-81 years) were recruited in this study. Nine lower extremity ROMs (hip flexion, hip extension, hip abduction, hip adduction, internal and external hip rotation, knee flexion, ankle dorsiflexion, and ankle plantar flexion) were bilaterally measured. The classification and regression tree methodology was used to develop a model that identifies fall experience for the past 12 months. Results: Twenty-seven participants reported falling in the past 12 months. The model included left ankle dorsiflexion, left hip flexion, and right hip external rotation ROMs. The area under the receiver operating characteristic curve of this model was 0.710 (95% confidence interval, 0.596-0.825). Conclusion: The accuracy of the model that considers lower extremity ROMs is moderate for the fall experience in community-dwelling older women.

Short-term posterior C1-C2 pedicle screw fixation without fusion to treat type II odontoid fracture among people under 60years.

Posterior C1-C2 pedicle screw fixation is a reliable technique used in treatment of type II odontoid fracture. However, the loss of cervical range of rotation motion (RORM) was inevitable. There were few studies focusing on the influence of short-term C1-C2 fixation with nonfusion technique to preserve cervical function in patients younger than 60years. The purpose of this study was to compare cervical RORM which was measured by an improved goniometer, and the clinical outcomes between short-term and long-term C1-C2 fixation techniques in the treatment of Grauer type 2B and 2C odontoid fracture. This study represents a retrospective analysis, including patients who underwent primary C1-C2 fixation surgery. These patients were divided into short-term and long-term groups based on whether underwent a fixation removal operation. The clinical results were collected and compared between the two groups. Independent T test and Chi-square analyses were used to identify significant differences between the two groups and dependent T test was used within each group. Statistical significance was set at p < .05. There were no severe postoperative complications, and all 60 patients achieved spinal stabilization after primary surgery. The mean rotation angle in the short-term group at last follow-up time was 138.39 ± 21.06°, which was better than 83.59 ± 13.06° in the long-term group (p < .05). The same statistical difference was observed in flexion-extension angle, which was 71.11 ± 18.73° in short-term group and 53.34 ± 18.23° in long-term group. The mean NDI score in short-term group at last follow-up time was 1.23 ± 0.86 and better than 8.24 ± 3.17 in long-term group. However, the VAS score in short-term group was 1.82 ± 0.54 which was worse compared to 0.64 ± 0.29 in long-term group. The results demonstrated that primary C1-C2 fixation with nonfusion technique could support satisfactory clinical effects. In addition, the removal of instruments after bony fusion could improve the function of cervical movement significantly in patients under 60years.

Gait and Knee Flexion In Vivo Kinematics of Asymmetric Tibial Polyethylene Geometry Cruciate Retaining Total Knee Arthroplasty.

The preservation of the posterior cruciate ligament in cruciate retaining (CR) total knee arthroplasty (TKA) designs has the potential to restore healthy knee biomechanics; however, concerns related to kinematic asymmetries during functional activities still exist in unilateral TKA patients. As there is a limited data available regarding the ability of the contemporary CR TKA design with concave medial and convex lateral tibial polyethylene bearing components to restore healthy knee biomechanics, this study aimed to investigate in vivo three-dimensional knee kinematics in CR TKA patients during strenuous knee flexion activities and gait. Using a combined computer tomography and dual fluoroscopic imaging system approach, in vivo kinematics of 15 unilateral CR TKA patients (comparison of replaced and contralateral nonreplaced knee) were evaluated during sit-to-stand, step-ups, single-leg deep lunge, and level walking. The patient cohort was followed-up at an average of 24.5 months ( ± 12.6, range 13-42) from surgical procedure. Significantly smaller internal knee rotation angles were observed for the contemporary CR TKA design during step-ups (2.6 ± 5.8 vs. 6.3 ± 6.6 degrees, p < 0.05) and gait (0.6 ± 4.6 vs. 6.3 ± 6.8 degrees, p < 0.05). Significantly larger proximal and anterior femoral translations were measured during sit-to-stand (34.7 ± 4.5 vs. 29.9 ± 3.1 mm, p < 0.05; -2.5 ± 2.9 vs. -8.1 ± 4.4 mm, p < 0.05) and step-ups (34.1 ± 4.5 vs. 30.8 ± 2.9 mm, p < 0.05; 2.2 ± 3.2 vs. -3.5 ± 4.5 mm, p < 0.05). Significantly smaller ranges of varus/valgus and internal/external rotation range of motion were observed for CR TKA, when compared with the nonoperated nee, during strenuous activities and gait. The preservation of the posterior cruciate ligament in the contemporary asymmetric bearing geometry CR TKA design with concave medial and convex lateral tibial polyethylene bearing components has the potential to restore healthy knee biomechanics; however, the study findings demonstrate that native knee kinematics were not fully restored in patients with unilateral asymmetric tibial polyethylene bearing geometry CR TKA during functional activities.

A Novel Construct Incorporating C2 Unilateral Pedicle and Contralateral Translaminar Screws for Occipitocervical Internal Fixation: An In Vitro Biomechanical Study

Occipitocervical fixation using bilateral C2 pedicle screws (C0-C2BiPS) and occipitocervical fixation using bilateral C2 translaminar screws (C0-C2BiLS) provide satisfactory stability. Bilateral fixation is not feasible for cases of C2 unilateral pedicle morphology abnormality and ipsilateral laminectomy. This study proposed and evaluated novel occipitocervical fixation using C2 unilateral pedicle screw and contralateral translaminar screws (C0-C2PSLS). In 6 human cadaveric specimens, an invitro experiment was performed with 2.0-Nm moment control in flexion-extension, lateral bending, and axial rotation to investigate biomechanical stability. Neutral zone and range of motion (ROM) between the occiput (C0) and C2 were measured in the intact state, after destabilization, and after sequential stabilization using C0-C2BiPS, C0-C2BiLS, and C0-C2PSLS constructs. Flexion-extension ROM of the intact specimens at C0-C2 was 27.4° ± 2.4°. Instrumentation with C0-C2PSLS, C0-C2BiPS, and C0-C2BiLS reduced flexion-extension ROM to 3.7° ± 1.3°, 4.7° ± 1.4°, and 4.5° ± 1.4°, respectively. In lateral bending, ROM values were 7.0° ± 0.6°, 4.5° ± 1.4°, 4.2° ± 1.4°, 2.7° ± 1.0°, respectively. In axial rotation, ROM values were 65.3° ± 5.7°, 2.5° ± 0.5°, 1.4° ± 0.5°, and 0.9° ± 0.6°, respectively. Comparing destabilized and intact specimens, all 3 constructs significantly reduced ROM and neutral zone values in flexion-extension, lateral bending, and axial rotation (P<0.05). Direct comparisons between the 3 constructs revealed no significant difference (P > 0.05). Novel C0-C2PSLS provides similar stabilization effect as C0-C2BiPS and C0-C2BiLS constructs and has potential for clinical use, especially for cases of C2 unilateral pedicle morphology abnormality and ipsilateral laminectomy.

A Biomechanical Comparison of 2 Hip Capsular Reconstruction Techniques: Iliotibial Band Autograft Versus Achilles Tendon Allograft

Background: Several techniques for hip capsular reconstruction have been described to address gross instability or microinstability due to capsular deficiency. However, objective biomechanical data to support their use are lacking. Purpose: To compare the kinematic effect of 2 capsular reconstruction techniques (iliotibial band [ITB] graft and Achilles tendon graft). Kinematic effect encompassed rotational range of motion (ROM) as well as joint translation in the coronal, sagittal, and axial planes. Study Design: Controlled laboratory study. Methods: 8 paired, fresh-frozen hemi-pelvises (16 hips) were tested on a custom-designed joint motion simulator in the intact state and after capsulectomy. Pairs were randomly allocated to either ITB or Achilles reconstruction and retested. Testing was performed at 0°, 45°, and 90° of flexion. Internal-external rotation (IR-ER) torques and abduction-adduction torques of 3 N·m were applied to the femur via a load cell at each position, and rotational ROM and joint translation in the coronal, sagittal, and axial planes were recorded. Results: At 45° and 90°, there was a significant effect of the condition of the hip on the total IR-ER (P = .004, effect size [ES] = 0.305; and P < .001, ES = 0.497; respectively). At 45°, mean ± SD total rotation was significantly greater for the capsulectomy (59.7°± 15.9°) state compared with intact (53.3°± 13.2°; P = .007). At 90°, reconstruction significantly decreased total rotation to 49.0°± 18.9° compared with a mean total rotation of 52.8°± 18.7° after capsulectomy (P = .02). No difference was seen in the total abduction-adduction of the hip between conditions. Comparisons of the 2 different reconstruction techniques showed no significant differences in total IR-ER or abduction-adduction ROM or joint translation in the coronal, sagittal, or axial planes. For translation, at both 0° and 45° there was a statistically significant effect of the condition on the medial-lateral translation (P = .033; ES = 0.204). Reconstruction, independent of technique, was successful in significantly decreasing (P = .030; P = .014) the mean medial-lateral translation at 0° and 45° of hip flexion from 5.2 ± 3.8 mm and 5.6 ± 4.0 mm to 2.8 ± 1.9 mm and 3.9 ± 3.2 mm, respectively. Conclusion: The integrity of the native hip capsule played a significant role in rotational stability, where capsulectomy significantly increased rotational ROM. Both ITB and Achilles reconstruction techniques restored normal rotational ROM of the hip at 90° of flexion as well as coronal plane stability at 0° and 45° of hip flexion. No differences were seen between ITB and Achilles reconstruction techniques. Clinical Relevance: Both capsular reconstruction techniques provide comparable joint kinematics, restoring rotation and translation to normal values with the exception of rotational ROM at 45°, which remained significantly greater than the intact state. The most significant results were the rotational stability at 90° of hip flexion and coronal plane stability at 0° and 45° of hip flexion, which were significantly improved compared with the capsulectomy state.

Are clinical outcomes of frozen shoulder linked to pain, structural factors or pain-related cognitions? An explorative cohort study

BackgroundIn frozen shoulder (FS), inflammatory-fibrotic adaptations in capsuloligamentous structures are typically linked to perceived glenohumeral stiffness, glenohumeral range of motion (ROM) restrictions and decreased arm function. However, ROM restrictions based on muscle guarding are suggested as well. ObjectivesTo assess differences between pain, perceived stiffness, ROM restrictions and arm function at time of diagnosis and at four months follow-up and to assess whether perceived stiffness, ROM restrictions and arm function relate to pain, structural and/or cognitive factors. Designobservational cohort study. MethodsIn persons with idiopathic FS, pain intensity at rest/at night/during activities (Numeric Rating Scale), perceived stiffness (Numeric Rating Scale), abduction/external rotation ROM (goniometry), and function (Disabilities of the Arm, Shoulder and Hand Questionnaire) were compared between both time points (Wilcoxon-signed rank tests). Spearman correlation coefficients assessed the relation between perceived stiffness, ROM and function on the one hand and structural factors (coracohumeral ligament (CHL) thickness and inferior glenohumeral recess (IGR) perimeter - arthroMRI), pain intensity and pain-related cognitions (Pain Catastrophizing Scale, Tampa Scale for Kinesiophobia) on the other hand. ResultsTwenty persons participated (14 female; 56±8yrs) and three persons dropped out at 4 months. Pain intensity, perceived stiffness, ROM and arm function improved over time. ROM was related to CHL-thickness and IGR-perimeter; perceived stiffness was related to pain intensity; and arm function was related to pain intensity and pain-related cognitions. ConclusionObjectively measured ROM is related to structural factors, while patient-reported outcomes are related to pain intensity and/or pain-related cognitions. Perceived stiffness does not relate to structural factors.

Shoulder complaints more likely in volleyball players with a thickened bursa or supraspinatus tendon neovessels

Shoulder problems are common in volleyball and greatly impede both training and player performance. Subacromial bursa (SAB) thickening and tendon neovascularity have shown relevance in other populations, but their relationship with the development of shoulder complaints has not been investigated in volleyball players or overhead-throwing athletes. The study aim was to examine the role of SAB thickness, neovascularization of the supraspinatus tendon, shoulder strength, range of motion (ROM), player position, and age in the development of shoulder complaints in professional volleyball players. Players underwent preseason baseline testing (n=86) and reported shoulder complaints during the subsequent 12-week period. Generalized estimating equations were used to model for probabilities of complaints after adjusting for player position, SAB side-to-side difference, neovessel presence, shoulder external rotation (ER) ROM, and age. Outside hitters and opposites were 12.2-fold more likely to develop complaints, and greater shoulder ER ROM increased risk by 8% for each additional degree. A side-to-side difference in SAB thickness ≥0.3mm in the dominant compared with the non-dominant arm was associated with a 10.2-fold increased risk. Those with neovessels were 6.5 times more likely to develop complaints. Players without neovessels and with normal SAB thickness were very unlikely to develop complaints. This stark contrast to players with neovessels or increased SAB thickness, where nearly half of the players developed complaints, is of interest. Players with current complaints at baseline presented with greater IR:ER strength ratios; however, neither strength nor IR ROM at baseline was associated with an increased risk of developing complaints.

Inclusion of the Acetabular Labrum Reduces Simulated Range of Motion of the Hip Compared With Bone Contact Models

PurposeTo determine whether inclusion of the acetabular labrum affects the maximum range of motion (ROM) during simulation of the flexion–adduction–internal rotation impingement examination.MethodsThree-dimensional surface reconstructions of the femur, hemi-pelvis, and labrum from computed tomography arthrography images of 19 participants were used to simulate maximum ROM during the flexion–adduction–internal rotation examination. Simulations were conducted for positions between 70° and 110° flexion and 0° and 20° adduction at 10° increments to measure maximum internal rotation and the position of contact between the femur and acetabular rim (bone-to-bone) or the femur and labrum (bone-to-labrum). Internal rotation angles and clock-face position values were compared between the 2 contact scenarios for each position.ResultsThe ROM in the bone-to-labrum contact model was significantly less than that of the bone-to-bone contact model for all evaluated positions (P ≤ .001, except at 110° flexion and 20° adduction, P = .114). The inclusion of the labrum reduced internal rotation by a median [interquartile range] of 18 [15, 25]° while altering the position of contact on the acetabular clock-face by –0:01 [–0:27, 0:16]. The variability in contact location for the bone-to-labrum contact scenario was nearly double that of the bone-to-bone contact scenario, as indicated by the interquartile range.ConclusionsInclusion of the anatomy of the acetabular labrum in collision models used to simulate impingement examinations reduced the internal rotation ROM by approximately 20° and increased variability in the location of contact relative to the acetabular rim.Clinical RelevanceWhile standard bone-to-bone contact ROM simulations may be informative with respect to the relative change in ROM based on a surgical intervention (e.g., pre- and post-osteochondroplasty for cam-type femoroacetabular impingement), they may not accurately represent the clinical ROM of the joint or the kinematic position at which damage may occur due to shape mismatch between the femur and acetabulum.

Clinical results of reverse shoulder arthroplasty for comminuted proximal humerus fractures in elderly patients: a comparison between nonporous stems versus trabecular metal stems.

BackgroundThis study compared the clinical results for nonporous stems vs. trabecular metal (TM) stems used in reverse shoulder arthroplasty (RSA) for comminuted proximal humeral fractures (CPHFs) in elderly patients.MethodsIn this retrospective study, a total of 41 shoulders (39 women) of patients with CPHF aged >70 years who underwent RSA were investigated. The minimum follow-up period was 2 years. A total of 15 shoulders were treated with Grammont-style RSA using nonporous stems (the G-RSA group), and 26 shoulders were treated with RSA combining TM stems (the FR-RSA group). The American Shoulder and Elbow Surgeons (ASES) shoulder score, Constant score, shoulder joint range of motion (ROM), and radiographic findings were compared between the 2 groups.ResultsASES scores and Constant scores were significantly higher in the FR-RSA group than in the G-RSA group. External rotation at the side in the FR-RSA group was significantly higher than that in the G-RSA group. In the FR-RSA and G-RSA groups, the union rates at the greater tuberosity (GT) were 88.5% and 46.7%, respectively, and scapular notching rates were 20% and 7.7%, respectively. Based on a subanalysis, the age was lower, body mass index was higher, and ASES scores, Constant scores, and external rotation ROM were higher in the GT union group than in the GT nonunion group.ConclusionGT bone union rates were high, and external rotation ROM of the shoulder joint were more improved for RSA using TM stems than those for RSA using nonporous stems in elderly patients with CPHF.

The effect of alar ligament transection on the rotation stress test: A cadaveric study

BackgroundThe rotation stress test is a pre-manipulative screening test used to examine upper cervical instability. This in vitro study simulates the clinical application of the rotation stress test before and after alar ligament transection. MethodsAfter the dissection of the superficial structures to the alar ligament and the fixation of C2, ten cryopreserved upper cervical columns were manually mobilized in right and left rotation without and with right alar ligament transection. Upper cervical rotation range of motion (RoM) and mobilization torque were recorded using the Vicon motion capture system and a load cell. FindingsLigament transection resulted in a larger rotation range of motion in all specimens (contralateral rotation (3.6°, 12.9%) and ipsilateral rotation (4.6°, 13.7%)). The mobilization torque recorded during rotation varied among the different specimens, with a trend towards reduced torque throughout the test in contralateral rotation. InterpretationThis study simulated the rotation stress test before and after alar ligament transection. Unilateral transection of the alar ligament revealed a bilateral increase of the upper cervical rotation. Additional in vivo studies are necessary to validate the results of this study in patients with suspicion of upper cervical instability.

RIGHT MIDDLE LOBE TORSION IN THE SETTING OF ABERRANT BRONCHIAL ANATOMY

SESSION TITLE: Medical Student/Resident Cardiothoracic Surgery Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Pulmonary torsion (PT) is defined as twisting of the entire lung or lobe around its bronchovascular pedicle. This disorder most commonly involves the right middle lobe (RML) following right upper lobe (RUL) lobectomy. The objective of this report is to describe a case of RML torsion following RUL lobectomy, in the setting of aberrant bronchial anatomy, which potentially led to this problem. CASE PRESENTATION: A 61-year-old African American woman with a RUL nodule, suspected to be cancerous, presented for RUL lobectomy. Flexible bronchoscopy revealed a right mainstem bronchus (RMB), which ended in a trifurcation of the upper, middle, and lower lobe bronchi. During thoracotomy, the inferior pulmonary ligament (IPL) was divided and RUL lobectomy was completed. Her major and minor fissures were noted to be partially complete and she had a short pedicle to the RML. As her risk of developing RML torsion was deemed to be low, no prophylactic fixation was done. Pathology confirmed the nodule to be a T1a N0M0 stage I adenocarcinoma. Post-operatively she complained of chest pain and hemoptysis. CT scan of the chest showed opacification of the right upper hemithorax, and RML torsion was suspected. Subsequent bronchoscopy showed that the RML bronchi were extrinsically compressed. Thoracoscopy demonstrated that the RML was torsed and engorged with venous blood (Figure 1). A thoracotomy and RML lobectomy were performed. Final pathology showed ischemic necrosis and hemorrhage. DISCUSSION: Ordinarily, the RMB gives rise to the RUL bronchus and the bronchus intermedius, which then bifurcates into the RML and right lower lobe (RLL) bronchi. The bronchus intermedius was absent in this patient and, instead, the RMB ended in a trifurcation of the RUL, RML, and RLL bronchi. The risk of RML torsion increases with division of the IPL in patients with complete pulmonary fissures and a lack of parenchymal bridges between the lobes prior to surgery. These factors increase the mobility of the RML, while the presence of a long pedicle predisposes to additional rotation along the bronchovascular pedicle.(1-3) This patient, despite lacking these risk factors, still developed RML torsion after RUL lobectomy. We speculate that the aberrantly located RUL takeoff, once resected, increased the range of rotational motion of the RML relative to the RLL, resulting in torsion of the RML. CONCLUSIONS: In patients at risk for RML torsion after RUL lobectomy, incomplete severing of the IPL and prophylactic inter-lobar fixation (or fixation to the thoracic wall or cardiac fat pad) are suggested. (2,3) Such measures may need to be considered in patients with a trifurcate RMB. Reference #1: Felson B. Lung torsion: Radiographic findings in 9 cases. Thoracic Radiology 1987 March; 162(3): 631-8. Reference #2: Moser E, Proto A. Lung torsion: Case report and literature review. Thoracic Radiology 1987 March; 162(3): 639-43. Reference #3: Kanemitsu S, Tenaka K, Suzuki H et al. Pulmonary torsion following right upper lobectomy. Ann Thorac Cardiovasc Surg 2006; 12: 417-9. DISCLOSURES: No relevant relationships by Batool Abuhalimeh, source=Web Response No relevant relationships by Joseph Lahorra, source=Web Response No relevant relationships by Tanya Marshall, source=Web Response No relevant relationships by Sanjiv Tewari, source=Web Response

The immediate effects of 5-minute high-force long axis distraction mobilization on the strain on the inferior ilio-femoral ligament and hip range of motion: A cadaveric study

BackgroundThe mechanical effects of hip joint mobilization on hip capsular-ligament tissue have never been studied. ObjectiveTo evaluate the strain on the inferior ilio-femoral (IFF) ligament after 5 min of high-force long-axis distraction mobilization (LADM) and to analyse the immediate effects on hip range of motion (ROM). DesignCross-sectional laboratory cadaveric study. MethodsThirteen hips hip joints were mobilized from nine fresh-frozen cadavers (mean age, 75.6 ± 7.8 years). High-force LADM in open-packed position was maintained during 5 min. Strain on IFF ligament was measured with a microminiature differential variable reluctance transducer at the beginning and just before the end of high-force LADM. Hip flexion, extension, abduction and internal rotation ROM were assessed using a universal goniometer before and after joint mobilization. ResultsThe strain on IIF ligament increased 20.2 ± 8.5% after 5 min of high-force LADM, showing a significant increase (p = 0.004). Hip ROM also increased significantly (p < 0.05) with large effect sizes (d > 0.8). ConclusionThe strain on IIF ligament and hip ROM increased significantly after 5 min of high-force LADM. The improvements on hip ROM appear to be related to the changes in the strain on capsular-ligament tissue after high-force LADM.