Biomechanical Evaluation of a Modified Internal Brace Construct for the Treatment of Ulnar Collateral Ligament Injuries

Biomechanical Characteristics of Ulnar Collateral Ligament Injuries Treated With and Without Augmentation: A Network Meta-analysis of Controlled Laboratory Studies

BACKGROUND

Treatment of ulnar collateral ligament (UCL) tears with suture tape augmentation has gained interest given preliminary reports of favorable biomechanical characteristics. No study to date has quantitatively assessed the biomechanical effects of multiple augmentation techniques relative to the native UCL.

PURPOSE

To perform a systematic review and meta-analysis of controlled laboratory studies to assess and comparatively rank biomechanical effects of UCL repair or reconstruction with or without augmentation.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

PubMed, OVID/Medline, and Cochrane databases were queried in January 2023. A frequentist network meta-analytic approach was used to perform mixed-treatment comparisons of UCL repair and reconstruction techniques with and without augmentation, with the native UCL as the reference condition. Pooled treatment estimates were quantified under the random-effects assumption. Competing treatments were ranked in the network meta-analysis by using point estimates and standard errors to calculate P scores (greater P score indicates superiority of treatment for given outcome).

RESULTS

Ten studies involving 206 elbow specimens in which a distal UCL tear was simulated were included. UCL reconstruction with suture tape augmentation (AugRecon) restored load to failure to a statistically noninferior magnitude (mean difference [MD], -1.99 N·m; 95% CI, -10.2 to 6.2 N·m; P = .63) compared with the native UCL. UCL reconstruction (Recon) (MD, -12.7 N·m; P < .001) and UCL repair with suture tape augmentation (AugRepair) (MD, -14.8 N·m; P < .001) were both statistically inferior to the native UCL. The AugRecon condition conferred greater load to failure compared with Recon (P < .001) and AugRepair (P = .002) conditions. AugRecon conferred greater torsional stiffness relative to all other conditions and was not statistically different from the native UCL (MD, 0.32 N·m/deg; 95% CI, -0.30 to 0.95 N·m/deg; P = .31). Medial ulnohumeral gapping was not statistically different for the AugRepair (MD, 0.30 mm; 95% CI, -1.22 to 1.82 mm; P = .70), AugRecon (MD, 0.57 mm; 95% CI, -0.70 to 1.84 mm; P = .38), or Recon (MD, 1.02 mm; 95% CI, -0.02 to 2.05 mm; P = .055) conditions compared with the native UCL. P-score analysis indicated that AugRecon was the most effective treatment for increasing ultimate load to failure and torsional stiffness, whereas AugRepair was the most effective for minimizing medial gapping.

CONCLUSION

AugRecon restored load to failure and torsional stiffness most similar to the parameters of the native UCL, whereas Recon and AugRepair did not restore the same advantageous properties at time zero. Medial ulnohumeral gapping during a valgus load was minimized by all 3 treatments. Based on network interactions, AugRecon was the superior treatment approach for restoring important biomechanical features of the UCL at time zero that are jeopardized during a complete distal tear.

Ulnar Collateral Ligament Reconstruction Is Commonly Performed Using a Palmaris Graft and Provides Favorable Patient Outcomes With Variable Return-to-Play and Postoperative Complication Rates: A Systematic Review

PURPOSE

To systematically review the literature to provide an updated evaluation of postoperative clinical outcomes, return to play (RTP), and postoperative complications after primary ulnar collateral ligament reconstruction (UCLR) in throwing and nonthrowing athletes at minimum 2-year follow-up.

METHODS

A literature search was performed on November 25, 2023, by querying the Embase, PubMed, and Scopus online databases using the 2020 Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. The inclusion criteria consisted of Level I to IV human clinical studies reporting postoperative outcomes and/or complications after primary UCLR with minimum 2-year follow-up. The exclusion criteria consisted of non-English-language studies; biomechanical, animal, and cadaveric studies; review articles; letters to the editor; and studies not reporting postoperative outcomes or complications. Study quality was evaluated using the Methodological Index for Non-Randomized Studies criteria. The incidence of reported complications among the included studies was extracted. Clinical outcome scores included the Kerlan-Jobe Orthopaedic Clinic Shoulder & Elbow (KJOC) score, Andrews-Timmerman (AT) score, and satisfaction score. RTP data were also extracted.

RESULTS

A total of 21 studies published from 2006 to 2023, consisting of 2,452 patients (2,420 male patients) with a mean age of 21.7 years (mean range, 12-65 years) and mean follow-up period of 50.5 months (mean range, 24-151.2 months), were included. The mean Methodological Index for Non-Randomized Studies score was 16 (range, 13-20). A total of 46% of patients (1,138 of 2,452) underwent concomitant ulnar nerve transposition. Palmaris graft was the most frequently used method (66.6%; n = 1,799), followed by hamstring graft (26.0%, n = 703). At the final follow-up, mean postoperative KJOC scores ranged from 72.0 to 88.0; mean AT scores, from 83.6 to 98.3; and mean satisfaction scores, from 86.1 to 98.3. The overall RTP rate ranged from 62.5% to 100% at a mean range of 9.5 to 18.5 months. The total incidence of complications ranged from 0% to 31.8%, with 0% to 7.4% of patients undergoing revision surgery.

CONCLUSIONS

UCLR was commonly performed using a palmaris graft, with concomitant ulnar nerve transposition reported in 46% of patients. At a mean follow-up of 50.5 months, mean postoperative KJOC scores ranged from 72 to 98.3, AT scores ranged from 83.6 to 98.3, and satisfaction scores ranged from 86.1 to 98.3, with variable RTP rates.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II to IV studies.

Elbow Ulnar Collateral Ligament Repair With Suture Augmentation Is Biomechanically Equivalent to Reconstruction and Clinically Demonstrates Excellent Outcomes: A Systematic Review

PURPOSE

To systematically review (1) biomechanical properties of augmented elbow ulnar collateral ligament (UCL) repair compared with reconstruction and (2) clinical efficacy and complication rates of UCL repair with and without augmentation.

METHODS

A systematic review was completed August 15, 2023, identifying articles that (1) biomechanically compared suture augmented UCL repair and reconstruction and (2) clinically evaluated medial elbow UCL repairs. Search terms included: "UCL repair" OR "internal brace" OR "suture augmentation" AND "UCL reconstruction." For inclusion, biomechanical studies compared augmented repair with reconstruction; clinical studies required clinical outcomes with minimum 6-month follow-up. Biomechanical data included torsional stiffness, gap formation, peak torque, and failure torque. Clinical data included return to previous level of play, time to return, functional outcomes, and complications.

RESULTS

In total, 8 biomechanical and 9 clinical studies were included (5 with and 4 without augmentation). In most biomechanical studies, augmented repairs demonstrated less gap formation, with equivalent torsional stiffness, failure load, and peak torque compared with reconstruction. Clinical outcomes in 104 patients without augmentation demonstrated return to previous level of 50% to 94% for nonprofessional athletes and 29% for professional baseball pitchers. Suture augmented repairs in 554 patients demonstrated return to previous level from 92% to 96%, at 3.8 to 7.4 months, with Kerlan Jobe Orthopaedic Clinic scores of 86 to 95. The overall complication rate for augmented UCL repair was 8.7%; most commonly ulnar neuropraxia (6%).

CONCLUSIONS

Biomechanically, UCL repair with augmentation provided less gapping with equivalent torsional stiffness and failure compared with reconstruction. Clinically, augmented UCL repair demonstrated excellent return to previous level of play and Kerlan Jobe Orthopaedic Clinic scores with modest complications and time to return. Augmented UCL repair is biomechanically equivalent to reconstruction and may be a viable alternative to reconstruction in indicated athletes.

CLINICAL RELEVANCE

UCL repair with suture augmentation is biomechanically equivalent to reconstruction and clinically demonstrates excellent outcomes.

Elbow Ulnar Collateral Ligament Repair With Suture Augmentation Results in Good Clinical Results, a Return-to-Play Rate Between 67% and 93%, and a Postoperative Complication Rate Up to 11.9%: A Systematic Review

Purpose

To review the Kerlan-Jobe Orthopaedic Clinic (KJOC) scores, return-to-play rates, and complications after ulnar collateral ligament (UCL) repair with suture augmentation.

Methods

A literature search of the PubMed and Scopus databases was conducted on February 17, 2023, using the terms "ulnar collateral ligament," "repair," "internal brace," and "suture augmentation." The search strategy was based on the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) protocol and included 4 articles published from 2019 to 2022. The inclusion criteria included studies reporting outcomes, return-to-play rates, and/or complications after UCL repair with suture augmentation. The exclusion criteria consisted of non-English language studies, case reports, cadaveric studies, animal studies, letters to the editor, studies with overlapping cohorts, and review articles. The risk of bias was evaluated using the Methodological Index for Non-Randomized Studies (MINORS) criteria.

Results

The final analysis included 4 studies with 510 patients (457 male and 53 female patients), ranging in age between 17.8 and 27.5 years, treated with repair and suture augmentation for UCL tears. In this review, we found a mean postoperative KJOC score ranging from 87.9 to 92.6. The overall rate of return to play at the preinjury level or at a higher level than the preinjury level ranged from 67% to 93%; the mean time to return to play ranged from 6.7 to 17.6 months. The postoperative complication rate in this review ranged from 0% to 11.9%. Among the complications, the most common were ulnar nerve paresthesia (range, 0%-8.2%) and postoperative medial elbow pain (range, 0%-3.1%). Overall, the reoperation rate ranged from 0% to 3.4%. No reruptures were reported.

Conclusions

UCL repair with the use of suture augmentation results in postoperative KJOC scores ranging from 87.9 to 92.6, a return-to-play rate between 67% and 93%, and a postoperative complication rate up to 11.9%.

Level of Evidence

Level IV, systematic review of Level IV studies.

Dual Bracing for Ulnar Collateral Ligament Injuries Restores Native Valgus Laxity and Native Medial Joint Gapping of the Elbow

Background

Despite growing evidence on the role of the posterior ulnar collateral ligament (pUCL) in elbow stability, current ligament bracing techniques are mainly focused on the anterior ulnar collateral ligament (aUCL). A dual-bracing technique combines the repair of the pUCL and aUCL with a suture augmentation of both bundles.

Purpose

To biomechanically assess a dual-bracing approach addressing aUCL and pUCL for humeral-sided complete UCL lesions to restore medial elbow laxity without overconstraining.

Study Design

Controlled laboratory study.

Methods

A total of 21 unpaired human elbows (11 right, 10 left; 57.19 ± 11.7 years) were randomized into 3 groups to compare dual bracing with aUCL suture augmentation and aUCL graft reconstruction. Laxity testing was performed with 25 N applied 12 cm distal to the elbow joint for 30 seconds at randomized flexion angles (0°, 30°, 60°, 90°, and 120°) for the native condition and then for each surgical technique. A calibrated motion capture system was used for assessment, allowing the 3-dimensional displacement during the complete valgus stress cycle between the optical trackers to be quantified as joint gap and laxity. The repaired constructs were then cyclically tested through a materials testing machine starting with 20 N for 200 cycles at a rate of 0.5 Hz. The load was increased stepwise by 10 N for 200 cycles until displacement reached 5.0 mm or complete failure occurred.

Results

Dual bracing and aUCL bracing resulted in significantly (P = .045) less joint gapping at 120° of flexion compared with aUCL reconstruction. No significant differences in valgus laxity were found among the surgical techniques. Within each technique, there were no significant differences between the native and the postoperative state in valgus laxity and joint gapping. No significant differences between the techniques were observed in cycles to failure and failure load.

Conclusion

Dual bracing restored native valgus joint laxity and medial joint gapping without overconstraining and provided similar primary stability regarding failure outcomes as established techniques. Furthermore, it was able to restore joint gapping in 120° of flexion significantly better than aUCL reconstruction.

Clinical Relevance

This study provides biomechanical data on the dual-bracing approach that may help surgeons to consider this new method of addressing acute humeral UCL lesions.

Medial Ulnar Collateral Ligament Repair With Augmentation: A Systematic Review and Meta-analysis of Preclinical Studies

Background

Reconstruction is the gold standard treatment for medial ulnar collateral ligament (MUCL) injuries. However, recent studies show a successful and renewed interest in direct suture repair, particularly in young athletes. Repair augmentation with a suture tape may provide greater stability, enabling healing of the MUCL while protecting the repair at higher valgus loads.

Purpose

To perform a systematic review and meta-analysis on whether MUCL repair with augmentation provides a similar biomechanical profile to the traditional MUCL reconstruction.

Study Design

Systematic review.

Methods

The Cochrane Controlled Register of Trials, PubMed, Medline, and Embase were used to perform a systematic review and meta-analysis using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria with the following search terms: ("ulnar collateral ligament" OR "medial ulnar collateral ligament") AND ("internal brace" OR "augmentation" OR "suture tape"). Data pertaining to certain biomechanical properties (gap formation, failure to torque [ultimate load to failure], stiffness, degree of valgus opening, and modes of failure) were extracted. The pooled outcome data were analyzed by random- and fixed-effects models. A total of 203 abstracts were identified through the aforementioned databases.

Results

After abstract and full-text screening, 6 biomechanical studies were included. All were on cadaveric elbows, with 53 repairs with augmentation and 53 reconstructions compared. There were no differences between the 2 in regard to ultimate load to failure (standard mean difference [SMD], -0.34 N·m; 95% CI, -1.36 to 0.68; P = .51) and rotational stiffness (SMD, 0.26; 95% CI, -1.14 to 1.66; P = .72). Despite a trend in resistance to gapping with augmented repair, this was not significant (SMD, -0.53; 95% CI, -1.08 to 0.01; P = .06). Augmented repairs were more likely to fail by pullout or at the suture-tendon/anchor-suture interface (odds ratio [OR], 12.19; 95% CI, 4.17 to 35.62; P < .00001), while failure by fracture was more common with reconstruction (OR, 5.75; 95% CI, 2.07 to 15.99; P = .0008).

Conclusion

MUCL augmented repair establishes the required time-zero structural properties without the need for a tendon graft. However, future clinical studies are necessary to determine its true effectiveness as well as its success at higher levels of professional sport.

Intersurgeon Consistency of Ulnar Collateral Ligament Repair With Internal Brace: A Biomechanical Analysis

BACKGROUND

Injury to the ulnar collateral ligament (UCL) of the medial elbow has been treated successfully with ligament repair augmented with internal brace. Previous work has shown that this procedure does not overconstrain the ulnohumeral joint; however, the procedures were conducted by a single surgeon, which controlled for anchor placement and graft tensioning.

PURPOSE/HYPOTHESIS

Our purpose was to evaluate the reproducibility of contact mechanics and joint torque after UCL repair with internal brace as performed by different surgeons compared with repair by a single surgeon. It was hypothesized that there would be no significant difference in elbow contact mechanics, valgus torque, or torsional stiffness between the 2 groups.

STUDY DESIGN

Controlled laboratory study.

METHODS

Nine pairs of fresh-frozen cadaveric elbows were tested biomechanically under 3 conditions: UCL-intact (UCL-I), UCL-deficient (UCL-D), and UCL-repaired with internal brace augmentation (UCLR-IB). For each pair, 1 elbow was repaired by a single surgeon, and the contralateral elbow was repaired by 1 of 9 other surgeons. Testing consisted of valgus torsion between 0° and 5° with the elbow positioned at 90° of flexion. Ulnohumeral contact mechanics and overall joint torque and stiffness were measured and compared between surgeon groups.

RESULTS

There were no statistically significant differences between the single-surgeon and multiple-surgeon groups regarding contact area (P = .83), contact force (P = .27), peak pressure (P = .26), or peak force (P = .30); however, contact pressure was significantly affected (P = .02) by surgeon group. Compared with UCL-I, both UCL-D and UCLR-IB conditions had a significant overall effect on contact area (P = .004) and contact force (P = .05); however, contact pressure (P = .56), peak pressure (P = .27), and peak force (P = .24) were not affected by injury condition. Measurements of elbow torque (P = .28) and stiffness (P = .98) were not significantly different between surgeon groups.

CONCLUSION

UCL repair with internal brace provided consistent results among several surgeons when compared with a single surgeon. The procedure did not lead to joint overconstraint while also returning the ligament to near-intact levels of resisting valgus stress.

CLINICAL RELEVANCE

UCL repair with internal brace augmentation is a reproducible surgical technique that has good clinical outcomes in the literature.

Utilization of Internal Bracing in Elbow Medial UCL Stabilization: From Biomechanics to Clinical Application and Patient Outcomes

Ulnar collateral ligament (UCL) reconstruction has been successfully utilized to treat symptomatic UCL insufficiency in overhead athletes. Despite the overall success of the procedure, attempts have been made to improve upon the original technique with the goal of hastening return to sport. Most recently, there has been interest in repairing or reconstructing the native ligament with internal brace (IB) augmentation. Biomechanical cadaveric studies assessing UCL repair with IB augmentation have attempted to evaluate the efficacy of this treatment; however, the literature is seemingly divided on its benefit. Preliminary clinical studies suggest internal bracing may allow a faster return to sport than conventional techniques. The purpose of this review was to provide an analysis of the current evidence on IB augmentation in UCL repair of the elbow as it pertains to biomechanical advantages/disadvantages, reported surgical techniques, and clinical outcomes in comparison with traditional UCL reconstruction techniques.

Suture tape augmentation improves laxity of MCL repair in the ACL reconstructed knee

PURPOSE

Medial collateral ligament (MCL) injury is very common and surgical repair is sometimes necessary. Especially in the setting of simultaneous anterior cruciate ligament reconstruction (ACLR) as the ACL is the secondary restraint against valgus stress. The goal of this study was to evaluate knee biomechanics after suture repair of the MCL augmented with suture tape, as compared to MCL repair alone, in the setting of concomitant ACL reconstruction (ACLR).

METHODS

Fifteen fresh-frozen human cadaveric knees were tested using a six-degrees-of-freedom robotic system under four loadings: (a) an 89.0 N anterior tibial load, (b) a 5.0 Nm internal and external rotation torque, (c) a 10.0 Nm valgus load, (d) a 7.0 Nm valgus load combined with 5.0 Nm internal rotation torque as a static simulated pivot-shift. The tested conditions were ACLR with the following states: (1) MCL intact, (2) MCL deficient, (3) MCL Repair, and (4) MCL repair augmented with suture tape (MCL Repair + ST). Under the different knee loadings, the tibial displacement, and the force in either the intact MCL, suture repaired MCL or repaired MCL-suture tape complex was measured.

RESULTS

While neither the MCL Repair nor the MCL Repair + ST restored valgus rotation to the MCL intact state, displacement was significantly smaller after MCL Repair + ST (p < 0.05). The knee rotation under external rotation torque in MCL Repair + ST did not differ MCL intact (n.s.), while with MCL Repair the rotation was significantly greater (p < 0.05). MCL Repair + ST did not cause an over-constraint of the knee in any of the tested loading conditions.

CONCLUSION

In a combined ACL-reconstruction-MCL-repair model, MCL Repair augmented with suture tape improved valgus and external rotation laxity when compared to MCL suture repair alone. Suture tape augmentation may provide this additional means of stabilization and can be added at the time of surgical repair of the MCL. Clinically this may result in lower failure rates and less residual laxity after MCL repair, as well as shorter immobilization times and faster return to play.

Lateral Elbow Laxity Is Affected by the Integrity of the Radial Band of the Lateral Collateral Ligament Complex: A Cadaveric Model With Sequential Releases and Varus Stress Simulating Everyday Activities

BACKGROUND

An elongation of the radial lateral collateral complex (R-LCL) can provoke symptomatic minor instability of the lateral elbow leading to lateral elbow pain. Biomechanical models investigating the effects of elongation and partial or complete lesions of the R-LCL on lateral elbow stability are lacking.

PURPOSE

To evaluate how partial and complete R-LCL release affects radiocapitellar joint stability in a setting of controlled varus load and progressive soft tissue release.

STUDY DESIGN

Controlled laboratory study.

METHODS

Ten fresh-frozen cadaveric specimens were obtained and mounted on a custom-made support to control elbow flexion and extension and to allow for controlled varus loading. Stress tests were performed on all intact specimens under gravity load alone, a 0.5-kg load applied to the hand, and a 1-kg load applied to the hand. After load application, anteroposterior radiographs were obtained. The following release sequence was applied to all specimens: release of the anterior half of the common extensor origin, pie crusting of the R-LCL, and R-LCL release. After each release, stress tests and radiographs were performed. The varus joint angulation of the elbow (α) was measured by 2 examiners as the main outcome parameter.

RESULTS

Significant changes in α from the initial condition occurred after each release, and a significant effect of varus load on α was documented for all release steps. A significant effect of the releases on α could be documented for all identical varus load conditions. A linear regression model was generated to describe the effect of varus load on α.

CONCLUSION

Varus loads simulating everyday activities produce changes in the varus joint angulation of the elbow already in the intact specimen, which are linearly dependent on the applied moment and persist after release of the lateral stabilizing structures. With progressive load, a pie crusting of the R-LCL is the minimal procedure able to provoke a significant change in the varus joint angulation, and a complete R-LCL release produces additional increase in the varus joint angulation in all testing conditions.

CLINICAL RELEVANCE

These findings confirm the role of the R-LCL as static lateral stabilizer, supporting a pathological model based on its insufficiency and culminating with a symptomatic minor instability of the lateral elbow.

Biomechanical assessment of docking ulnar collateral ligament reconstruction after failed ulnar collateral ligament repair with suture augmentation

BACKGROUND

Ulnar collateral ligament (UCL) repair with single-strand suture augmentation has been introduced as a viable surgical option for throwers with acute UCL tears. For the original single-strand suture augmentation construct, revision UCL reconstructions can be challenging owing to the bone loss at the site of anchor insertion in the center of the sublime tubercle. This biomechanical study assessed a small-diameter (1.5-mm) ulnar bone tunnel technique for double-strand suture-augmented UCL repair that may be more easily converted to salvage UCL reconstruction if necessary, as well as a salvage UCL reconstruction with a docking technique after a failed primary suture-augmented UCL repair.

METHODS

In 7 fresh-frozen cadaveric upper extremities (mean age, 66.3 years), a custom shoulder testing system was used to simulate the late cocking phase of throwing. The elbow valgus opening angle was evaluated using a MicroScribe 3DLX device for sequentially increasing valgus torque (from 0.75 to 7.5 Nm in 0.75-Nm increments) at 90° of flexion. Valgus angular stiffness (in newton-meters per degree) was defined as the correlation of sequentially increasing valgus torque with the valgus opening angle through simple linear regression (slope of valgus torque - valgus opening angle curve). Four conditions were tested: intact elbow, distal UCL avulsion, primary UCL repair with double-strand suture augmentation using small-diameter bone tunnels, and subsequent docking UCL reconstruction in the same specimen. Load-to-failure tests were performed for primary UCL repair with double-strand suture augmentation and subsequent docking UCL reconstruction.

RESULTS

With increasing elbow valgus torque, the valgus opening angle increased linearly in each condition (R² ≥ 0.98, P < .001). Distal UCL avulsion resulted in significantly decreased angular stiffness compared with the intact UCL (P < .001). Both UCL repair with double-strand suture augmentation and subsequent UCL reconstruction showed significantly increased angular stiffness values compared with distal UCL avulsion (P < .001 and P < .001, respectively). On load-to-failure testing, there was no significant difference in stiffness, yield torque, and ultimate torque between the primary suture-augmented UCL repair and the subsequent UCL reconstruction (P = .11, P = .77, and P = .38, respectively). In all specimens undergoing the small-diameter ulnar bone tunnel technique for double-strand suture-augmented UCL repair, failure occurred by retear of the repaired ligament without causing an ulnar bone bridge fracture.

CONCLUSION

Primary UCL repair with double-strand suture augmentation using small-diameter bone tunnels was able to restore valgus stability. When failure occurs, this technique retains enough cortical bone to permit subsequent docking UCL reconstruction.

Elbow Ulnar Collateral Ligament Shoelace Repair with Internal Bracing for Treating Throwing Athletes Who Have Ulnar Collateral Ligament Instability

This Technical Note aimed to present a surgical technique of ulnar collateral ligament (UCL) shoelace repair using suture anchors and double suture tapes in combination with internal bracing to correct UCL instability along with epiphyseal avulsion of the medial epicondyle in throwing athletes Skeletally immature throwing athletes playing baseball and softball are at a risk of sustaining medial epicondyle epiphyseal separation that can result in UCL instability, predisposing to elbow UCL disruption later. There are several surgical techniques that can restore elbow UCL function and stability. In cases where large fragments of the medial epicondyle are present in skeletally immature athletes, the residual bony fragment and the shortened, chronically injured UCL make surgical treatment quite challenging. Recent studies have shown that UCL repair with internal bracing can effectively treat acute UCL injury. However, this procedure is not ideal for restoring large disruption of the UCL such as fragmentation. Here, we present a surgical technique of UCL shoelace repair using suture anchors with double suture tapes in combination with internal bracing for correcting UCL instability concurrent with epiphyseal fragmentation of medial epicondyle in throwing athletes.

The Biomechanical Effects of Augmentation With Flat Braided Suture on Dorsal Intercarpal Ligament Capsulodesis for Scapholunate Instability

PURPOSE

Selecting treatment for scapholunate (SL) instability is notoriously difficult. Many methods of reconstruction have been described, but no procedure demonstrates clear superiority. New methods proposed use internal bracing (IB) with suture anchors and flat braided suture (FBS), alone or as an augmentation with tendon autograft for SL ligament injuries. Our goal was to use computed tomography (CT) to analyze alignment of the SL joint after 3 different modes of fixation of SL instability: after reconstruction with IB incorporating either tendon autograft or the dorsal intercarpal ligament (DICL), or DICL capsulodesis without FBS.

METHODS

Ten fresh-frozen, matched-pair, forearm-to-hand specimens were used. Serial sectioning of the SL stabilizing ligaments was performed and the SL interval was measured with CT. We reconstructed the SL ligament with DICL capsulodesis alone (DICL) or with IB augmented with either tendon autograft (IB plus T) or DICL (DICL plus IB). The SL interval was measured with CT. Specimens underwent 500 weighted cycles on a jig and were reimaged. Differences in SL interval after repair and cycling were compared.

RESULTS

Dorsal intercarpal ligament capsulodesis augmented with IB best maintained the SL interval before and after cycling. Dorsal intercarpal ligament capsulodesis alone was inferior to DICL plus IB and IB plus T both before and after cycling.

CONCLUSIONS

Dorsal intercarpal ligament capsulodesis augmented with IB appears to maintain better SL joint reduction than IB with tendon autograft.

CLINICAL RELEVANCE

This work serves as a necessary step for further study of the biomechanical strength and clinical application of FBS technology in the reconstruction of SL instability. Flat braided suture augmentation of DICL capsulodesis may provide another option to consider for reconstruction of SL instability.

Ulnar Collateral Ligament Repair of the Elbow-Biomechanics, Indications, and Outcomes

PURPOSE OF REVIEW

Traditionally medial elbow injuries in overhead athletes have been treated with ulnar collateral ligament (UCL) reconstruction as first described by Dr. Frank Jobe. Recent literature has shown favorable outcomes in select patients treated with UCL repair. Newer techniques utilizing suture augmentation demonstrate biomechanical profiles as good or better than the native state and/or reconstruction. This review aims to evaluate these biomechanical studies and the clinical outcomes of ulnar collateral ligament repair with suture augmentation.

RECENT FINDINGS

UCL repair has favorable outcomes in select patients with specific tear type patterns. Clinical outcomes have shown return to play rates of 92-97% with mean time of 2.5-6 months post-operatively. Biomechanical data comparing UCL repair to reconstruction techniques have shown improved resistance to common forces applied to the elbow during overhead activities. Additionally, suture tape augmentation dramatically improves stability of ligament repair without over-constraining the elbow. Initial ulnar collateral ligament repair data was poor, and thus UCL reconstruction became the mainstay of treatment for overhead athletes. Recent studies evaluating the biomechanical properties as well as clinical outcomes have demonstrated favorable data when UCL repair is performed. When considering the drawbacks of a prolonged recovery associated with reconstruction, UCL repair is a viable option in select patients.

Ultrasound evaluation shows increase in laxity after partial common extensor origin detachment but not after additional lesion of the radial band of the lateral collateral ligament

PURPOSE

The lateral elbow musculature conveys a dynamic valgus moment to the elbow, increasing joint stability. Muscular or tendinous lesions to the anterior half of the common extensor origin (CEO) may provoke a deficiency in the elbow dynamic stabilizers, regardless of their traumatic, degenerative, or iatrogenic aetiology. Furthermore, a role for the radial band of the lateral collateral ligament (R-LCL) has been postulated in the aetiology of lateral elbow pain. This study aimed to evaluate the effects of sequential lateral releases with dynamic ultrasound, evaluating its capability to detect lesions of the CEO and of the R-LCL.

METHODS

Ultrasound investigation of the lateral compartment of the elbow was performed on nine cadaveric specimens with a 10 MHz linear probe in basal conditions, after the release of the anterior half of the CEO and after complete R-LCL release. The lateral joint line widening (λ) was the primary outcome parameter, measured as the linear distance between the humeral and radial articular surfaces.

RESULTS

The release of the anterior half of the CEO significantly increased λ by 200% compared to the starting position (p = 0.0008) and the previously loaded position (p = 0.0015). Conversely, further release of the R-LCL caused only a marginal, non-significant increase in λ.

CONCLUSIONS

Ultrasound evaluation can detect changes related to tendon tears or muscular avulsions of the CEO and can depict lateral elbow compartmental patholaxity by assessing articular space widening while scanning under dynamic stress. However, it cannot reliably define if the R-LCL is injured. Iatrogenic damage to the CEO should be carefully avoided, since it causes a massive increase in compartmental laxity.