Influence of Continuous Elbow Valgus Stress on the Medial Elbow Joint Space

Background: To investigate the effect of ulnar collateral ligament stretching due to the "creep phenomenon," the effect of accumulating elbow valgus stress on ligaments must be clarified. Purpose: To evaluate the effect of continuous elbow valgus stress on the medial elbow joint space (JS). Study Design: Controlled laboratory study. Methods: The authors measured the JS of the nondominant elbow joints of 20 healthy male university students (age, 21.4 ± 0.5 years; height, 171.4 ± 6.5 cm; weight, 65.7 ± 9.1 kg). The participants were seated with their shoulder at 90° of abduction and external rotation and their elbow at 30° of flexion, and elbow valgus stress was maintained at loads of 30 and 60 N using a Telos stress device. The JS was measured on ultrasound images of the medial elbow joint with the elbow in the start limb position (0 N) and then immediately (0 seconds) and at 60, 120, 180, 240, and 300 seconds after loading. In addition, muscle activity of the pronator teres muscle during JS measurement was monitored to examine the presence or absence of defensive contraction due to pain. Analysis of variance and the Bonferroni method for post hoc testing were used for statistical analysis. Results: No participants showed defensive contractions of the pronator teres. At 30 N, JS was significantly larger 60 seconds after loading compared with immediately after loading ( P = .007). At 60 N, JS was significantly larger after 120 seconds, as the loading time of valgus stress increased, compared with immediately after loading ( P = .002). Conclusion: JS was significantly larger immediately after loading of valgus stress, with an increase in continuous elbow valgus stress after 60 seconds at 30 N and after 120 seconds at 60 N. These results suggest that a creep phenomenon may develop around the soft tissue of the elbow when loaded by a continuous valgus stress. Clinical Relevance: JS is significantly increased by continuous elbow valgus stress.

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Elbow valgus stability of the transverse bundle of the ulnar collateral ligament

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-04760-1 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Mutsuaki Edama ◽

Kanta Matsuzawa ◽

Hirotake Yokota ◽

Ryo Hirabayashi ◽

Chie Sekine ◽

...

Keyword(s):

Subcutaneous Tissue ◽

Load Condition ◽

Ulnar Collateral Ligament ◽

Joint Space ◽

Collateral Ligament ◽

Valgus Stress ◽

Limb Position ◽

Intact State ◽

Significant Difference ◽

Telos Stress Device

Abstract Background The purpose of this study was to clarify elbow valgus stability of the transverse bundle (TB). We hypothesized that the transverse bundle is involved in elbow valgus stability. Methods Twelve elbows of six Japanese Thiel-embalmed cadavers were evaluated. The skin, subcutaneous tissue and origin of forearm flexors were removed from about 5 cm proximal to the elbow to about 5 cm distal to the elbow, and the ulnar collateral ligament was dissected (intact state). The cut state was defined as the state when the TB was cut in the middle. The joint space of the humeroulnar joint (JS) was measured in the intact state and then in the cut state. With the elbow flexed to 30°, elbow valgus stress was gradually increased to 30, 60 N using the Telos Stress Device, and the JS was measured by ultrasonography under each load condition. Paired t-testing was performed to compare the JS between the intact and cut states under each load. Results No significant difference in JS was identified between the intact and cut state at start limb position. The JS was significantly higher in the cut state than in the intact state at both 30 N and 60 N. Conclusion The findings from this study suggested that the TB may be involved in elbow valgus stability.

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Changes in Medial Elbow Joint Space When Elbow Valgus Stress Is Applied at Different Limb Positions and Loads In Vivo

Orthopaedic Journal of Sports Medicine ◽

10.1177/23259671211045981 ◽

2021 ◽

Vol 9 (11) ◽

pp. 232596712110459

Author(s):

Kanta Yoshioka ◽

Kanta Matsuzawa ◽

Tomoya Ikuta ◽

Sae Maruyama ◽

Mutsuaki Edama

Keyword(s):

Repeated Measures ◽

Elbow Joint ◽

Ulnar Collateral Ligament ◽

Elbow Flexion ◽

Sports Injury ◽

Joint Space ◽

Muscle Contractions ◽

Collateral Ligament ◽

Valgus Stress

Background: Ulnar collateral ligament (UCL) injury is a common sports injury among overhead-throwing athletes and causes medial elbow pain and instability. UCL injury is generally diagnosed based on symptoms, physical findings, and image evaluation. To standardize the method for evaluating elbow valgus instability, more information is needed regarding changes in the medial elbow joint space (JS) in healthy elbows. Purpose/Hypothesis: The purpose of this study was to measure the JS during the application of elbow valgus stress at different elbow flexion angles and loads and to clarify the presence of defensive muscle contractions during elbow valgus stress. It was hypothesized that the JS will differ according to different limb positions and loads and that defensive contractions will occur when elbow valgus stress is >90 N. Study Design: Controlled laboratory study. Methods: Elbow joints on the nondominant side were examined in 20 healthy male university students (mean age, 21 ± 0.2 years) at 30°, 60°, and 90° of elbow flexion. To create valgus stress on the elbow, loads of 30, 60, 90, 120, and 150 N were applied with a Telos stress device and with gravity stress on the forearm. The medial JS was measured ultrasonographically during the application of elbow valgus stress. Electrodes were attached to the pronator teres muscle, and defensive muscle contractions were measured using electromyography during the application of elbow valgus stress. Repeated-measures analysis of variance and paired t tests were used to compare the JS at each elbow angle and each valgus stress load, and the Bonferroni method was used as a post hoc test. Results: At 30° of elbow flexion, the JS was significantly higher at 30 N versus 0 N and at 60 N versus 0 or 30 N ( P ≤ .018 for all). At 60° of flexion, the JS was significantly higher at 30 N versus 0 N, at 60 N versus 0 and 30 N, and at 90 N versus 0, 30, and 60 N ( P ≤ .024 for all). At 90° of elbow flexion, the JS was significantly higher at 30 N versus 0 N and at 60 N versus 0 and 30 N ( P ≤ .028 for all). Defensive muscle contraction did not occur at any elbow flexion angles at elbow valgus stress ≤60 N. Conclusion: The lack of muscular contraction at elbow valgus stress ≤60 N may reflect the function of the medial collateral ligament. Clinical Relevance: Elbow valgus stress ≤60 N allows for the evaluation of the joint opening.

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Medial Elbow Joint Laxity in Professional Baseball Pitchers

The American Journal of Sports Medicine ◽

10.1177/03635465980260031301 ◽

1998 ◽

Vol 26 (3) ◽

pp. 420-424 ◽

Cited By ~ 121

Author(s):

Todd S. Ellenbecker ◽

Angelo J. Mattalino ◽

Erik A. Elam ◽

Roger A. Caplinger

Keyword(s):

Elbow Joint ◽

Joint Space Width ◽

Ulnar Collateral Ligament ◽

Joint Space ◽

Professional Baseball ◽

Stress Radiography ◽

Collateral Ligament ◽

Valgus Stress ◽

Baseball Pitchers ◽

Space Width

Injuries to the ulnar collateral ligament frequently occur in throwing athletes because of large, repetitive valgus stresses to the elbow during the cocking and acceleration phases of throwing. Identification of injury to this ligament is important in evaluating the throwing elbow. The purpose of this study was to determine whether differences in medial elbow laxity exist between the dominant and nondominant extremities in uninjured baseball pitchers. Forty uninjured professional baseball pitchers were tested bilaterally with a Telos GA-IIE stress radiography device. Joint space width between the trochlea of the humerus and the coronoid process of the ulna was measured on anteroposterior radiographs obtained with no stress applied and with a 15-daN valgus stress. Results showed significant differences between the medial joint space opening of the dominant and nondominant elbows with no stress applied. With stress, the dominant elbow opened 1.20 0.97 mm, while the nondominant elbow opened 0.88 0.55 mm. A significantly greater difference in medial joint space opening between the stressed and unstressed elbows was measured in the dominant elbow compared with the nondominant elbow (0.32 0.42 mm). This study identifies increased medial elbow laxity in the dominant arm in uninjured pitchers.

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Relationship between ulnar collateral ligament thickness and joint hypermobility in young adults

Journal of Orthopedics and Orthopedic Surgery ◽

10.29245/2767-5130/2021/2.1140 ◽

2021 ◽

Vol 2 (2) ◽

pp. 24-29

Author(s):

Peter R. Reuter ◽

Arie J. van Duijn ◽

Kaylee R. Fichthorn ◽

Lacy Mroz

Keyword(s):

Undergraduate Students ◽

Elbow Joint ◽

Ulnar Collateral Ligament ◽

Joint Hypermobility ◽

Ultrasound Images ◽

Collateral Ligament ◽

Valgus Stress ◽

Cross Sectional ◽

Significant Difference ◽

Joint Gapping

Joint hypermobility is largely understood as a dysfunction of collagen fibers within connective tissues, allowing for a range of motion markedly increased over validated normal values. The ulnar collateral ligament (UCL) of the elbow provides stability to the elbow during valgus stress and, thus, has great significance in overhead throwing sports due to its susceptibility to injury. Our cross-sectional study explored the relationship between the length and width of the anterior bundle of the ulnar collateral ligament of the elbow and joint hypermobility. Two hundred and eighty-four undergraduate students completed a Beighton score assessment. Ultrasound images of the participants’ UCL were obtained in both arms at rest and under gravity induced valgus force. Sixty-one participants reported hypermobility in at least one elbow joint, and hypermobility in one elbow joint was correlated with hypermobility in the other. There were moderate correlations between UCL thickness and joint gapping between left and right elbow joints. However, there was no significant difference in UCL anterior bundle thickness or medial elbow joint gapping at rest or under valgus stress between those with and without hypermobile elbow joints. The thickness of the anterior bundle of the UCL and humeroulnar joint gap at rest moderately correlates to corresponding thickness and width under valgus stress. There is no significant difference in UCL anterior bundle thickness or joint width in people with elbow hypermobility and those without.

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Medial Elbow Instability Resulting From Partial Tears of the Ulnar Collateral Ligament: Stress Ultrasound in a Cadaveric Model

The American Journal of Sports Medicine ◽

10.1177/0363546520947065 ◽

2020 ◽

Vol 48 (11) ◽

pp. 2613-2620

Author(s):

Michael C. Ciccotti ◽

Sommer Hammoud ◽

Christopher C. Dodson ◽

Steven B. Cohen ◽

Levon N. Nazarian ◽

...

Keyword(s):

Ulnar Collateral Ligament ◽

Joint Space ◽

Nonoperative Treatment ◽

Collateral Ligament ◽

Valgus Stress ◽

Diagnostic Modality ◽

Partial Tear ◽

Partial Tears ◽

Early Reconstruction ◽

Anterior Posterior

Background: There is consensus that most complete ulnar collateral ligament (UCL) injuries in throwers would benefit from surgical intervention. Optimal treatment for partial UCL tears remains controversial. Stress ultrasonography has become a well-accepted diagnostic modality for assessing UCL injury. Hypothesis: Partial UCL tears will result in an intermediate increase in ulnohumeral joint space gapping as compared with that of an intact UCL and a complete UCL tear, but the degree of joint space gapping will vary by anatomic location of the partial tear. Study Design: Controlled laboratory study. Methods: Twenty-one cadaveric elbows were divided into 7 groups representing different anatomic locations of UCL partial tears. Partial tears were simulated by cutting 50% of the measured width of the UCL at 6 locations: distal anterior/posterior, midsubstance anterior/posterior, and proximal anterior/posterior. A seventh partial tear was created by partially elevating the undersurface of the distal UCL to simulate the radiographic “T-sign.” Valgus stress (15 daN) was applied to each cadaveric elbow at 30° of flexion using a standardized device. Each specimen was tested intact, partially torn, and completely torn. At each state, joint space was measured using stress ultrasonography, and the difference in joint space from unstressed to stressed (delta) was recorded. Results: There were 10 right and 11 left upper extremity specimens. The mean delta was 0.58 mm for the intact state and <0.75 mm in all groups. Both distal partial tear groups had mean deltas <0.75 mm, similar to intact elbows. Proximal tears and the T-sign demonstrated intermediate deltas (0.99-1.23 mm). Midsubstance partial tears demonstrated the largest deltas (1.57-2.03 mm), similar to those of the complete tears. All complete tear groups had a mean delta >1.5 mm (1.54-3.03 mm). Conclusion: These findings suggest that partial tears introduce a spectrum of instability from functionally intact to completely torn. As a result, some may be biomechanically amenable to nonoperative treatment, while others would be indicated for early reconstruction. Further research into the biological and biomechanical determinants of nonoperative treatment failure will assist with more precise treatment recommendations. Clinical Relevance: Describing the biomechanical consequences of different, clinically significant partial UCL tears potentially allows more precise recommendations for operative and nonoperative treatment.

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Wrist Flexion Exercise Increases the Width of the Medial Elbow Joint Space During a Valgus Stress Test

Journal of Ultrasound in Medicine ◽

10.1002/jum.14779 ◽

2018 ◽

Vol 38 (4) ◽

pp. 959-966 ◽

Cited By ~ 2

Author(s):

Nathaniel Millard ◽

Andrew DeMoss ◽

Gary McIlvain ◽

Joseph A. Beckett ◽

John J. Jasko ◽

...

Keyword(s):

Elbow Joint ◽

Stress Test ◽

Joint Space ◽

Wrist Flexion ◽

Valgus Stress

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Changes in elbow joint contact area in symptomatic valgus instability of the elbow in baseball players

Scientific Reports ◽

10.1038/s41598-021-99193-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Kyosuke Numaguchi ◽

Daisuke Momma ◽

Yuki Matsui ◽

Jun Oohinata ◽

Takayoshi Yamaguchi ◽

...

Keyword(s):

Contact Area ◽

Elbow Joint ◽

Ulnar Collateral Ligament ◽

Imaging Data ◽

Valgus Stress ◽

Contact Areas ◽

Joint Contact ◽

Valgus Instability ◽

Ct Data ◽

Dominant Side

AbstractThe aim of this study was to evaluate the joint contact area of the dominant side and that of the non-dominant side without valgus instability in symptomatic pitchers. Ten symptomatic elbow medial ulnar collateral ligament (UCL) deficient baseball pitchers participated in this study. Computed tomography (CT) data from the dominant and non-dominant elbows were obtained with and without elbow valgus stress. The CT imaging data of each elbow joint were reconstructed using a 3D reconstruction software package, and the radiocapitellar and ulnohumeral joint contact areas were calculated. The center of the contact area and the translation from the position without stress to the position with valgus stress were also calculated. With elbow valgus stress, the contact area changed, and the center of the radiocapitellar joint contact area translated significantly more laterally in the dominant elbow than in the non-dominant elbow (p = 0.0361). In addition, the center of the ulnohumeral joint contact area translated significantly more posteriorly in the dominant elbow than in the non-dominant elbow (p = 0.0413). These changes in contact areas could be the reason for cartilage injury at the posterior trochlea in pitchers with UCL deficiency.

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Medial Elbow Joint Space Increases With Valgus Stress and Decreases When Cued to Perform A Maximal Grip Contraction

The American Journal of Sports Medicine ◽

10.1177/0363546518755149 ◽

2018 ◽

Vol 46 (5) ◽

pp. 1114-1119 ◽

Cited By ~ 12

Author(s):

Brett S. Pexa ◽

Eric D. Ryan ◽

Joseph B. Myers

Keyword(s):

Upper Extremity ◽

Repeated Measures ◽

Elbow Joint ◽

Muscle Activation ◽

Elbow Dislocation ◽

Joint Space ◽

Flexor Muscle ◽

Valgus Stress ◽

Bonferroni Adjustment

Background: Previous research indicates that the amount of valgus torque placed on the elbow joint during overhead throwing is higher than the medial ulnar collateral ligament (UCL) can tolerate. Wrist and finger flexor muscle activity is hypothesized to make up for this difference, and in vitro studies that simulated activity of upper extremity musculature, specifically the flexor digitorum superficialis and flexor carpi ulnaris, support this hypothesis. Purpose: To assess the medial elbow joint space at rest, under valgus stress, and under valgus stress with finger and forearm flexor contraction by use of ultrasonography in vivo. Study Design: Controlled laboratory study. Methods: Participants were 22 healthy males with no history of elbow dislocation or UCL injury (age, 21.25 ± 1.58 years; height, 1.80 ± 0.08 m; weight, 79.43 ± 18.50 kg). Medial elbow joint space was measured by use of ultrasonography during 3 separate conditions: at rest (unloaded), under valgus load (loaded), and with a maximal grip contraction under a valgus load (loaded-contracted) in both limbs. Participants lay supine with their arm abducted 90° and elbow flexed 30° with the forearm in full supination. A handgrip dynamometer was placed in the participants’ hand to grip against during the contracted condition. Images were reduced in ImageJ to assess medial elbow joint space. A 2-way (condition × limb) repeated-measures analysis of variance and Cohen’s d effect sizes were used to assess changes in medial elbow joint space. Post hoc testing was performed with a Bonferroni adjustment to assess changes within limb and condition. Results: The medial elbow joint space was significantly larger in the loaded condition (4.91 ± 1.16 mm) compared with the unloaded condition (4.26 ± 1.23 mm, P < .001, d = 0.712) and the loaded-contracted condition (3.88 ± 0.94 mm, P < .001, d = 1.149). No significant change was found between the unloaded and loaded-contracted conditions ( P = .137). Conclusion: Medial elbow joint space increases under a valgus load and then decreases when a maximal grip contraction is performed. This indicates that wrist and finger flexor muscle contraction may assist in limiting medial elbow joint space, a result similar to findings of previous research in vitro. Clinical Relevance: Muscle activation of the upper extremity limits the medial elbow joint space, suggesting that injury prevention programs for throwing athletes should incorporate exercises for the elbow, wrist, and hand to limit excessive medial elbow joint space gapping during activities that create high valgus load.

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Valgus Stability is Enhanced by Flexor Digitorum Superficialis Muscle Contraction of the Index and Middle Fingers

10.21203/rs.2.21691/v2 ◽

2020 ◽

Author(s):

Shota Hoshika ◽

Akimoto Nimura ◽

Norimasa Takahashi ◽

Hiroyuki Sugaya ◽

Keiichi Akita

Keyword(s):

Muscle Contraction ◽

Elbow Joint ◽

Ulnar Collateral Ligament ◽

Flexor Digitorum Profundus ◽

Flexor Digitorum Superficialis ◽

Collateral Ligament ◽

Valgus Stress ◽

The Difference ◽

Flexor Digitorum ◽

Healthy Males

Abstract Background: Flexor digitorum superficialis (FDS) muscle provides dynamic stabilization and medial elbow support for ulnar collateral ligament (UCL). The FDS contraction significantly affects the medial joint distance (MJD) through grip contraction. However, it remains unclear whether FDS activity alone contributes to medial elbow stability, or together with the activation of the flexor digitorum profundus during grip contraction, and which finger’s FDS is the main contributor to elbow stability. We investigated the resistive effects of isolated FDS contraction in individual fingers against valgus stress in the elbow joint using stress ultrasonography (US).Methods: We investigated 17 healthy males (mean age, 27 ± 5 years). Valgus stress US was performed using the Telos device, with the elbow at 30° flexion. MJD was measured for each arm during 3 separate conditions: at rest (unloaded), under valgus load (50 N) (loaded), and under valgus load with FDS contracted in individual fingers (loaded-contracted). Results: MJD was significantly longer when loaded (5.4 ± 0.4 mm) than unloaded (4.1 ± 0.2 mm, P = .007) or loaded-contracted (4.6 ± 0.3 mm, P = .003) for each finger. When loaded-contracted, MJD differed statistically between the index and ring fingers (P = .03) and between the middle and ring fingers (P = .04). However, the difference between the index and middle fingers was not statistically significant (P = .08). Conclusions: Individual FDS contraction, particularly of the index and middle fingers contributes most to stabilization against valgus stress. Thus, injury care programs should incorporate FDS exercises of these fingers.

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