Outcomes of Arthrodesis of the Metacarpophalangeal Joint of the Thumb for Sequelae of Collateral Ligament Injuries: A Series of 18 Cases with 6-Year Follow-Up.

Background: Untreated or insufficiently treated collateral ligament injuries of the thumb metacarpophalangeal (MP) joint can lead to instability or even osteoarthritis. Arthrodesis is one of the treatment options available for the treatment of the sequelae of collateral ligament injuries. The objective of our study was to evaluate the radiological, clinical and functional outcomes of MP joint arthrodesis performed for sequelae of collateral ligament injuries. Methods: We conducted a retrospective, single-centre study and reviewed the files of patients who had a thumb MP joint arthrodesis following a collateral ligament injury between 2011 and 2019. We collected patient's demographic data and the results of the radiological and clinical examinations. Results: Eighteen patients were included in the study. The average age was of 53.6 years and the time between injury to arthrodesis averaged 7 years. Four patients (22%) had nonunion. In the remaining 14 patients with solid union at an average of 72 months follow-up, the visual analogue pain score at rest was 0.14, the thumb opposition was 82%, grip strength 85%, tip pinch 92% and key pinch 79% of the contralateral side. Conclusions: The clinical and functional results of patients with a successful arthrodesis are satisfactory with restoration of good grip and pinch strength. Despite a lack of thumb MP joint flexion, stability allowed force transmission and may be preferred for manual workers. Level of Evidence: Level IV (Therapeutic).

Novel figure-of-eight reconstruction with free tendon graft for unrepairable collateral ligament of the thumb metacarpophalangeal joint.

OBJECTIVES: This study aimed to report surgical technique and clinical outcomes for a novel figure-of-eight collateral ligament reconstruction technique using palmaris longus autograft for chronic irreparable collateral ligament injury of the thumb metacarpophalangeal joint. MATERIAL AND METHODS: The Jobe elbow collateral ligament reconstruction method was adapted for thumb metacarpophalangeal joint collateral ligament reconstruction. Sixteen reconstructions (7 ulnar collateral ligament, 9 radial collateral ligament) using palmaris longus autograft were reviewed retrospectively. Surgery was performed at a mean 12 months post-injury. All 16 patients were followed up for more than 1 year. Metacarpophalangeal joint radial and ulnar deviation, metacarpophalangeal and interphalangeal joint range of motion, key pinch and grip strength, Glickel functional grade and QuickDASH score were evaluated. RESULTS: Preoperative radial or ulnar deviation improved from 19.3° to 5.3° postoperatively. Metacarpophalangeal range of motion improved from 31.5° to 46.6°, and interphalangeal range of motion from 48.4° to 65.6°. Preoperative key pinch and grip strength were respectively 49% and 81% of contralateral values and improved to 82% and 87%. On Glickel grade, 9 cases were excellent and 7 good. CONCLUSION: The novel Jobe-like figure-of-eight reconstruction technique using palmaris longus graft was useful for reconstructing irreparable thumb metacarpophalangeal joint instability without an incision on the opposite side or an additional implant. LEVEL OF EVIDENCE: Therapeutic study, level IV.

Biological Versus Nonbiological Reconstruction of the Ulnar Collateral Ligament of the Thumb Metacarpophalangeal Joint: A Retrospective Study.

PURPOSE: The purpose of this study was to compare clinical and radiologic outcomes of biological ligament reconstruction (BLR) versus nonbiological ligament reconstruction (NBLR) for chronic injuries involving the ulnar collateral ligament of the thumb's metacarpophalangeal joint. METHODS: Forty-two patients who underwent static BLR (n = 24) or NBLR (n = 18) were included in this retrospective analysis. Preoperative, postoperative, and contralateral thumb measurements (clinical evaluation, radiographs, and subjective outcome questionnaires) were compared over a mean of 38 months of follow-up. RESULTS: Average postoperative thumb metacarpophalangeal and interphalangeal joint ranges of motion were 2° to 54° and 0 to 71°, respectively, for BLR and 0° to 58° and 0° to 71°, respectively, for NBLR. Average grip and pinch strengths, relative to the unaffected hand, were 102% and 84% versus 103% and 89%, respectively. All patients demonstrated stability with a firm end point, compared with the unaffected thumb. The average Quick Disabilities of the Arm, Shoulder, and Hand score among all patients was 12 for the disability/symptom module, 0 for the sports module, and 17 for the work module. Stiffness was reported among four patients, and no patient sustained wound-related issues or other complications. CONCLUSIONS: Nonbiological ligament reconstruction of the thumb ulnar collateral ligament generates short-term outcomes comparable with those of BLR, potentially allowing for expedited recovery and rehabilitation. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Isometry of anteromedial reconstructions mimicking the deep medial collateral ligament depends on the femoral insertion.

PURPOSE: This study aimed to investigate the length change patterns of the native deep medial collateral ligament (dMCL) and potential anteromedial reconstructions (AMs) that might be added to a reconstruction of the superficial MCL (sMCL) to better understand the control of anteromedial rotatory instability (AMRI). METHODS: Insertion points of the dMCL and potential AM reconstructions were marked with pins (tibial) and eyelets (femoral) in 11 cadaveric knee specimens. Length changes between the pins and eyelets were then tested using threads in a validated kinematics rig with muscle loading of the quadriceps and iliotibial tract. Between 0° and 100° knee flexion, length change pattern of the anterior, middle and posterior part of the dMCL and simulated AM reconstructions were analysed using a rotary encoder. Isometry was tested using the total strain range (TSR). RESULTS: The tibiofemoral distance of the anterior dMCL part lengthened with flexion (+12.7% at 100°), whereas the posterior part slackened with flexion (-12.9% at 100°). The middle part behaved almost isometrically (maximum length: +2.8% at 100°). Depending on the femoral position within the sMCL footprint, AM reconstructions resulted in an increase in length as the knee flexed when a more centred position was used, irrespective of the tibial attachment position. Femoral positioning in the posterior aspect of the sMCL footprint exhibited <4% length change and was slightly less tight in flexion (min TSR = 3.6 ± 1.5%), irrespective of the tibial attachment position. CONCLUSION: The length change behaviour of potential AM reconstructions in a functionally intact knee is mainly influenced by the position of the femoral attachment, with different tibial attachments having a minimal effect on length change. Surgeons performing AM reconstructions to control AMRI would be advised to choose a femoral graft position in the posterior part of the native sMCL attachment to optimise graft length change behaviour. Given the high frequency of MCL injuries, sufficient restoration of AMRI is essential in isolated and combined ligamentous knee injuries. LEVEL OF EVIDENCE: There is no level of evidence as this study was an experimental laboratory study.

Valgus malalignment causes increased forces on a medial collateral ligament reconstruction under dynamic valgus loading: A biomechanical study.

PURPOSE: To investigate the forces on a medial collateral ligament (MCL) reconstruction (MCLR) relative to the valgus alignment of the knee. METHODS: Eight fresh-frozen human cadaveric knees were subjected to dynamic valgus loading at 400 N using a custom-made kinematics rig. After resection of the superficial medial collateral ligament, a single-bundle MCLR with a hamstring tendon autograft was performed. A medial opening wedge distal femoral osteotomy was performed and fixed with an external fixator to gradually adjust the alignment in 5° increments from 0° to 10° valgus. For each degree of valgus deformity, the resulting forces acting on the MCLR were measured through a force sensor and captured in 15° increments from 0° to 60° of knee flexion. RESULTS: Irrespective of the degree of knee flexion, increasing valgus malalignment resulted in significantly increased forces acting on the MCLR compared to neutral alignment (p < 0.05). Dynamic loading at 5° valgus resulted in increased forces on the MCLR at all flexion angles ranging between 16.2 N and 18.5 N (p < 0.05 from 0° to 30°; p < 0.01 from 45° to 60°). A 10° valgus malalignment further increased the forces on the MCLR at all flexion angles ranging between 29.4 N and 40.0 N (p < 0.01 from 0° to 45°, p < 0.05 at 60°). CONCLUSION: Valgus malalignment of the knee caused increased forces acting on the reconstructed MCL. In cases of chronic medial instabilities accompanied by a valgus deformity ≥ 5°, a realigning osteotomy should be considered concomitantly to the MCLR to protect the graft and potentially reduce graft failures. LEVEL OF EVIDENCE: Level III.

The mechanics of the collateral ligaments in the metacarpophalangeal joints: A scoping review.

BACKGROUND: The metacarpophalangeal (MCP) joint's collateral ligaments have been extensively debated, with no clear consensus on their mechanics. Understanding their function is crucial for comprehending joint movement and stability. METHODS: A thorough search was conducted across databases, including PubMed, Scopus, Cochrane library and grey literature. A total of 59 articles were identified, and after rigorous evaluation, six articles were included in the review. RESULTS: The analysis underscores two principal findings. Firstly, the principal and accessory collateral ligaments exhibit consistent tension influenced by the MCP joint's position. This tension varies across different sections of the ligaments. Secondly, the ligaments' interaction with the joint structure plays a pivotal role in defining the range of motion of the joint. CONCLUSION: Preliminary findings from this review indicate that MCP joint collateral ligament tension varies with joint position. Increased tension in the principal collateral ligament during flexion and isometric behavior of its volar portion in extension are observed. The accessory ligament may tighten during extension. The shape of the metacarpal head appears to influence this tension. These insights, while informative, call for further detailed research to deepen our understanding of MCP joint mechanics.

Ligament Sparing Elbow Hemiarthroplasty: A Novel Technique for the Management of Distal Humeral Fractures.

Intra-articular distal humerus fractures present various challenges with a wide array of treatment options. Open reduction internal fixation remains the treatment of choice. In older patient populations with poor bone quality and short-end segment fractures with articular comminution, open reduction internal fixation, however, may bring on unsurmountable technical challenges. Total elbow arthroplasty and elbow hemiarthroplasty (EHA) may offer superior functional outcomes in these cases. During EHA for fractures, the medial and lateral columns are reconstructed with the collateral ligaments to restore elbow stability. We hypothesize that in coronal sheer fracture patterns where the columns are intact, maintaining the native collateral ligaments and columns will provide both an anatomic and stable elbow joint. We introduce the ligament sparing EHA technique for unreconstructible coronal shear fractures. We describe this novel technique and compare our postoperative outcomes in 2 patients who underwent this surgery to those described in the literature. The postoperative Disabilities of the Arm, Shoulder, and Hand scores for the 2 patients were 13.8 and 10.3, respectively. The Mayo Elbow Performance Score for the 2 patients were 80 and 85, respectively. The operative arm presented a grip strength of 82% and 89% when compared with the contralateral arm, for the patients respectively. The range of motion varied between 78% and 100% of the contralateral arm for both patients. Although our results are promising and the ligament sparing EHA technique may be a more anatomic option in certain fracture patterns, further research with larger cohorts and multiple surgeons is needed to reinforce our results.

Single-Strand "Short Isometric Construct" Medial Collateral Ligament Reconstruction Restores Valgus and Rotational Stability While Isolated Deep MCL and Superficial MCL Reconstruction Do Not.

BACKGROUND: Historical MCL (medial collateral ligament) reconstruction (MCLR) techniques have focused on the superficial MCL (sMCL) to restore valgus stability while frequently ignoring the importance of the deep MCL (dMCL) in controlling tibial external rotation. The recent recognition of the medial ligament complex importance has multiple studies revisiting medial anatomy and questioning contemporary MCLR techniques. PURPOSE: To assess whether (1) an isolated sMCL reconstruction (sMCLR), (2) an isolated dMCL reconstruction (dMCLR), or (3) a novel single-strand short isometric construct (SIC) would restore translational and rotational stability to a knee with a dMCL and sMCL injury. STUDY DESIGN: Controlled laboratory study. METHODS: Biomechanical testing was performed on 14 fresh-frozen cadaveric knee specimens using a custom multiaxial knee activity simulator. The specimens were divided into 2 groups. The first group was tested in 4 states: intact, after sectioning the sMCL and dMCL, isolated sMCLR, and isolated dMCLR. The second group was tested in 3 states: intact, after sectioning the sMCL and dMCL, and after single-strand SIC reconstruction (SICR). In each state, 4 loading conditions were applied at 0°, 20°, 40°, 60°, and 90° of knee flexion: 8-N·m valgus torque, 5-N·m external rotation torque, 90-N anterior drawer, and combined 90-N anterior drawer plus 5-N·m tibial external rotation torque. Anterior translation, valgus rotation, and external rotation of the knee were measured for each state and loading condition using an optical motion capture system. RESULTS: sMCL and dMCL transection resulted in increased laxity for all loading conditions at all flexion angles. Isolated dMCLR restored external rotation stability to intact levels throughout all degrees of flexion, yet valgus stability was restored only at 0° of flexion. Isolated sMCLR restored valgus and external rotation stability at 0°, 20°, and 40° of flexion but not at 60° or 90° of flexion. Single-strand SICR restored valgus and external rotation stability at all flexion angles. In the combined anterior drawer plus external rotation test, isolated dMCL and single-strand SICR restored stability to the intact level at all flexion angles, while the isolated sMCL restored stability at 20° and 40° of flexion but not at 60° or 90° of flexion. CONCLUSION: In the cadaveric model, single-strand SICR restored valgus and rotational stability throughout the range of motion. dMCLR restored rotational stability to the knee throughout the range of motion but did not restore valgus stability. Isolated sMCLR restored external rotation and valgus stability in early flexion. CLINICAL RELEVANCE: In patients with anteromedial rotatory instability in the knee, neither an sMCLR nor a dMCLR is sufficient to restore stability.

Dynamic Stress Ultrasound Assessment of Professional Baseball Players' Elbows After Ulnar Collateral Ligament Reconstruction.

BACKGROUND: There is a paucity of data analyzing dynamic stress ultrasound (SUS) findings in elite pitchers who have undergone ulnar collateral ligament (UCL) reconstruction (UCLR) and returned to sport. PURPOSE: To identify longitudinal, perioperative changes in the elbows of professional baseball pitchers who have undergone UCLR and to compare these findings with a matched cohort of healthy pitchers. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: This study used prospectively collected data from dynamic elbow SUS analyses of professional baseball pitchers within a single Major League Baseball organization. Pitchers were divided into 2 cohorts: a UCLR cohort and healthy cohort. The UCLR cohort eligibility included availability of (1) SUS from preseason of injury/UCLR and (2) SUS from ≥2 years after surgery. These players were 1:1 matched to players with no history of upper extremity injury to form the healthy cohort. Ligament thickness and ulnohumeral joint space at rest and under stress were directly measured. Joint laxity was calculated by subtracting joint space at rest from joint space under stress. The term "relative" was used to describe calculated differences where nondominant measurements were subtracted from dominant-side measurements. RESULTS: Eight pitchers were included in the UCLR group and matched to 8 healthy pitchers (mean age at initial SUS examination, 19.6 years). At a minimum follow-up of 2 years, there were no significant differences between groups in terms of relative or dominant arm rest space, stress space, or laxity. Longitudinally (final measurements - baseline measurements), the mean relative ulnohumeral rest space decreased in the UCLR group and increased in the healthy group (-0.36 mm vs +0.50 mm; P = .032). The finding of increased UCL thickness in the UCLR group was expected, as UCL grafts are typically thicker than native ligaments. CONCLUSION: Ulnhohumeral joint stability was achieved after UCLR as indicated by similar rest space, stress space, and joint laxity in dominant arms compared with a matched healthy cohort. A significant decrease in relative rest space after UCLR may represent the achievement of stability in surgery patients. Alternatively, the increase in ulnohumeral rest space seen in the healthy cohort may represent adaptive changes from pitching at a professional level.

The Utility of Stress Ultrasound in Identifying Risk Factors for Elbow Ulnar Collateral Ligament Tear: A Longitudinal Study of 203 Professional Baseball Players.

BACKGROUND: Injuries to the medial ulnar collateral ligament (UCL) are common among baseball pitchers due to repetitive stress on the soft tissue stabilizers of the elbow during pitching. Dynamic stress ultrasound (SUS) can be used to evaluate the UCL and ulnohumeral joint to identify anatomic risk factors of those who will require UCL reconstruction (UCLR). PURPOSE: To determine whether any adaptive or morphological changes detectable on SUS can predict injury to the UCL in professional baseball pitchers. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 203 professional baseball pitchers who underwent SUS at preseason training sessions over the course of 18 years were categorized into 1 of 2 groups: those without a history of shoulder, arm, elbow, or forearm surgery or injuries (healthy cohort; n = 184) and those who underwent UCLR the same season as SUS (UCLR cohort; n = 19). Ligament thickness, joint spacing, and laxity were compared. An additional matched cohort analysis was conducted using 10 players from each group to detect differences in the progression of UCL and ulnohumeral joint measures in the year before injury. RESULTS: The UCLR cohort, when compared with the healthy cohort, had higher relative (ie, nondominant-side measurements subtracted from dominant-side measurements) resting ulnohumeral joint space (median, 0.50 vs 0.20 mm, respectively; P = .006) and higher rates of hypoechoic foci (57.9% vs 30.4%, respectively; P = .030). Players of both groups had similar dominant UCL thickness (P = .161), ulnohumeral joint space at rest (P = .321), space under stress (P = .498), and laxity (P = .796). Groups did not differ in terms of relative UCL thickness, ulnohumeral joint space under stress, or relative laxity. In the year before UCL injury, the UCLR cohort, compared with the matched healthy cohort, had a greater increase in mean dominant UCL thickness (0.94 vs -0.60 mm, respectively; P = .038) and a greater increase in relative median UCL thickness (1.35 vs -0.35 mm, respectively; P = .045). Players in the healthy cohort were statistically older than those in the UCLR cohort (23 vs 22 years, respectively; P = .004). No differences in ulnohumeral stress spacing or laxity were detected. CONCLUSION: SUS of players who underwent UCLR demonstrated a progressive increase in UCL thickness over 1 year, higher rates of hypoechoic foci, and increased ulnohumeral rest space compared with SUS of uninjured players.

[Injuries of the ankle ligaments]. / Bandverletzungen des oberen Sprunggelenks.

Lateral ligament injuries are the most common injuries of the ankle joint and are usually treated with early weight bearing after a short period of immobilization. If the clinical presentation is suspicious, additional injuries to the deltoid ligament complex and the syndesmosis should be considered. The indications for additional diagnostics should be generously applied. Injuries to the deltoid ligament usually occur as part of a complex ankle injury and should also be addressed in the surgical treatment of accompanying injuries. Chronic instability in this area necessitates complex bony and soft tissue procedures. Syndesmotic injuries with insufficiency of the capsule-ligament apparatus are frequent in ankle fractures and are stabilized during fracture treatment. Isolated syndesmotic instability should also be surgically treated as chronic injuries are usually associated with poor clinical results and early osteoarthritis.

Anconeus-sparing minimally invasive approach for lateral ulnar collateral ligament reconstruction using a triceps tendon autograft is an effective and safe treatment for chronic posterolateral instability of the elbow.

BACKGROUND: Surgical treatment helps to restore stability of the elbow in patients with posterolateral rotatory instability (PLRI). The anconeus muscle is one of the most important active stabilizers against PLRI. A minimally invasive anconeus-sparing approach for lateral ulnar collateral ligament (LUCL) reconstruction using a triceps tendon autograft has been previously described. The purpose of this study was to evaluate the outcome of this intervention and identify risk factors that influenced the clinical and patient-reported outcomes. METHODS: Sixty-one patients with chronic PLRI and no previous elbow surgery who underwent surgical reconstruction of the LUCL using a triceps tendon autograft in a minimally invasive anconeus-sparing approach during 2012 and 2018 were evaluated. Outcome measures included a clinical examination and the Oxford Elbow Score (OES) and the Mayo Elbow Performance Score (MEPS) questionnaires. Subjective patient outcomes were evaluated with the visual analog scale (VAS) for pain and the Subjective Elbow Value (SEV). Integrity of the common extensor tendons and centering of the radial head were assessed preoperatively on standardized magnetic resonance images (MRIs). RESULTS: Fifty-two patients were available at final follow-up. The mean age of patients was 51 ± 12 years with a mean follow-up of 53 ± 14 months (range 20-76). Clinical examination after surgery (n = 41) showed no clinical signs of instability in 98% of the patients (P < .001) and a nonsignificant improvement in range of motion. OES, MEPS, and VAS scores averaged 40 ± 10 of 48 points, 92 ± 12 of 100 points, and 1 ± 2 points, respectively, all corresponding with good or excellent outcomes. The SEV was 88%, indicating very high satisfaction with the surgery. Only 1 patient had revision surgery due to pain, and there were no reported postoperative complications in this cohort. A radial head subluxation in the MRI correlated significantly with worse postoperative outcomes. CONCLUSIONS: The anconeus-sparing minimally invasive technique for posterolateral stabilization of the elbow using a triceps tendon autograft is an effective and safe treatment for chronic posterolateral instability of the elbow with substantial improvements in elbow function and pain relief with a very low rate of persistent clinical instability.

Release or transection of superficial medial collateral ligament during open-wedge high tibial osteotomy demonstrated similar clinical outcomes and valgus laxity.

PURPOSE: To analyse whether valgus laxity and clinical outcomes differ depending on whether the superficial medial collateral ligament (sMCL) is released or transected during medial open-wedge high tibial osteotomy (MOWHTO). METHODS: Consecutive patients who underwent MOWHTO and subsequent radiological follow-up for at least 2 years were retrospectively evaluated. The patients were divided into release and transection groups, according to the sMCL manipulation technique. Each patient was assessed for the following variables on valgus stress radiographs taken before surgery and at the 12- and 24-month follow-ups: the absolute value of valgus (ABV) and side-to-side difference (SSD) between the affected and normal sides. The differences between preoperative SSD and those at 12 and 24 months were respectively calculated and defined as delta SSD (ΔSSD). The Visual Analogue Scale, Lysholm knee, International Knee Documentation Committee subjective, and Knee Injury and Osteoarthritis Outcome scores were used to evaluate patient-reported outcomes. RESULTS: Eighty-five patients were included in the study. Forty-two patients (49.6%) underwent sMCL release, and the remaining 43 patients (50.4%) underwent sMCL transection. No significant differences were observed in the ABV and SSD of valgus laxity at the different time points between the two groups (n.s.). Furthermore, no significant differences were observed in the ΔSSD at the 12- and 24-month follow-ups between the two groups (n.s.). Significant improvement from preoperative values was observed in all patient-reported outcomes (p < 0.001), with no significant differences between the two groups at any time point (n.s.). CONCLUSION: Significant improvements in clinical outcomes were observed, regardless of the technique used. Postoperative valgus laxity did not occur with either technique. The transection technique, which can be performed more simply and quickly, demonstrated similar clinical outcomes and valgus laxity to the release technique. LEVEL OF EVIDENCE: Level III.

Simple acute postero-lateral elbow dislocation: A historical perspective.

PURPOSE: The aims of this study were to summarize (1) the historical knowledge of the posterolateral elbow dislocation (PLED) pattern and the biomechanical, radiographic, and clinical data that engendered its evolution; and (2) to help clinicians better understand the management of PLED. METHODS: A literature search was performed using Ovid, Scopus and Cochrane Library, and the Medical Subject Headings vocabulary. Results are discussed as a chronologic review of the relevant literature between 1920-2022. RESULTS: In 1966 Osborn and Cotterill were the first to describe posterolateral rotatory instability (PLRI) causing the PLED. Several theories on PLED were then published by others surgeons as our understanding of elbow biomechanics continued to improve. Multiple treatment protocols have been designed based on the aforementioned theories. Conservative and surgical treatment for PLED provides excellent functional outcomes. However, high rates of persistent pain stiffness and instability have been reported long-term, and no single approach to treatment has been widely accepted. CONCLUSION: Despite a growing body of biomechanical evidence, there is no consensus surgical indication for the treatment of PLED. Both conservative and surgical management result in satisfactory functional outcomes after PLED. However, elevated rates of residual pain, and instability have also been described and may limit heavy labor and sports participation. The next challenge for elbow surgeons will be to identify those patients who would benefit from surgical stabilization following PLED.

Editorial Commentary: Ulnar Collateral Ligament Repair With Suture Augmentation May Be Superior to Reconstruction for Proximal or Distal Tears With Good- Quality Tissue.

Ulnar collateral ligament (UCL) tears in the elbow have been rising in recent years, most specifically in baseball players. Although many of these tears occur in professional (minor and major league) baseball pitchers, there has been a dramatic rise in UCL injuries in adolescents, at a rate of 9% per year. Although some UCL tears can be treated conservatively, those that fail conservative treatment often require surgical intervention to allow players to return to sport. Although UCL reconstruction has been the gold standard in surgical treatment for many years, UCL repair with suture augmentation has grown in popularity. Initial results of UCL repair with suture augmentation have been promising, and a recent review comparing UCL repair with suture augmentation from both a biomechanical and clinical outcome perspective confirms that UCL repair may be superior to reconstruction for patients with proximal or distal tears and good quality UCL tissue for repair.

Material Properties of Fiber Bundles of the Superficial Medial Collateral Ligament of the Knee Joint.

The superficial medial collateral ligament (sMCL) of the human knee joint has functionally separate anterior and posterior fiber bundles. The two bundles are alternatively loaded as the knee flexion angle changes during walking. To date, the two bundles are usually not distinguished in knee ligament simulations because there has been little information about their material properties. In this study, we conducted quasi-static tensile tests on the sMCL of matured porcine stifle joints and obtained the material properties of the anterior bundle (AB), posterior bundle (PB), and whole ligament (WL). AB and PB have similar failure stress but different threshold strain, modulus, and failure strain. As a result, we recommend assigning different material properties (i.e., modulus and failure strain) to the two fiber bundles to realize biofidelic ligament responses in human body models. However, it is often inconvenient to perform tensile tests on AB and PB. Hence, we proposed a microstructural model-based approach to predict the material properties of AB and PB from the test results of WL. Such obtained modulus values of AB and PB had an error of 2% and 0.3%, respectively, compared with those measured from the tests. This approach can reduce the experimental cost for acquiring the needed mechanical property data for simulations.

Association Between Draft Order and Stress Sonography of the Ulnar Collateral Ligament of the Elbow in Professional Baseball Pitchers: An 18-Year Study.

BACKGROUND: The Major League Baseball (MLB) draft is a common route for players to enter professional baseball in the United States. Players taken in earlier rounds are typically higher-performing players. When looking at pitchers specifically, higher performance at the amateur level may be associated with an increased frequency of adaptive change in the throwing elbow. PURPOSE: To determine whether pitchers taken in earlier rounds of the MLB draft have a greater frequency or extent of pathological change in the elbow, as measured by dynamic stress ultrasound. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Dynamic stress ultrasounds (SUSs) were performed over 18 years on the dominant and nondominant arms of 651 professional pitchers. The 383 drafted players were grouped according to the round in which they were drafted (rounds 1-5, 6-10, 11-20, 21+). Groups were compared with respect to "relative" ulnar collateral ligament (UCL) thickness (dominant-nondominant), relative ulnohumeral joint laxity (joint space distance under stress minus joint space at rest), and the presence of pathology (calcifications, tears, hypoechoic foci, osteophytes). In addition, a subgroup analysis was done to compare the progression of SUS findings over 3 years in players for which data were available. RESULTS: Draft round groups did not differ by age, number of previous spring training, or handedness. Comparing baseline measurements, there was no significant relationship between draft round and relative UCL thickness (P = .932), relative laxity (P = .996), or presence of pathology detectable on SUS (P = .642). However, increased relative UCL thickness was significantly associated with the presence of pathology on SUS (odds ratio, 1.45; 95% CI, 1.26-1.69; P < .001). Longitudinally, there was no significant relationship between draft round and 3-year progression of relative laxity, relative UCL thickness, or clinical progression of pathology. CONCLUSION: Higher-performing pitchers are drafted earlier in the MLB draft. This may be attributable to peak pitch velocity, in-game performance, visibility gained during player showcases, or any number of other sport-specific variables. However, despite this, there was no significant relationship between draft round and adaptive changes to the elbow or specific properties of the UCL on stress ultrasound.

Ulnar Collateral Ligament Repair With Suture Tape Augmentation: Can You Overtighten?

BACKGROUND: There has been a renewed interest and, recently, wider implementation of ulnar collateral ligament (UCL) repair in throwing athletes because of improvement in ligament repair technology and corresponding outcome data. PURPOSE: To compare the biomechanical parameters and failure mode between 2 brace-tightening techniques for UCL repair. STUDY DESIGN: Controlled laboratory study. METHODS: Eleven matched pairs of cadaveric arms were procured. One limb from each pair underwent UCL repair with suture tape augmentation with either (1) attempted restoration of physiologic ligament tension or (2) maximal tension. Each specimen was subjected to 10 cycles of subfailure valgus torque at 90º of flexion in the intact state after UCL avulsion and then after UCL repair. Specimens were then torqued to failure. Articular contact mechanics, linear gap distance, angular displacement, failure torque, failure stiffness, and suture tape pull-through length were recorded. Two-way analysis of variance and paired t tests were used to test for statistical differences. RESULTS: There was a significant effect (P = .01) of tightening on joint contact area. There was a significant decrease in gap distance (P = .03) and angular displacement (P = .004) from the torn condition to the repaired condition for the maximum tension group, without a significant difference in gap distance from the intact condition. Failure torque and stiffness were not significantly different between groups, although there was a significant difference (P = .001) in the overall suture tape pull-through length. CONCLUSION: Although there are potential physiologic changes at time zero-including significant decreases in contact area, normalized gap distance, and normalized angular displacement with maximal tension repair-examination of failure biomechanics suggests that these effects may be mitigated over time within the construct by suture tape pull-through at the tape-anchor interface. Neither method of UCL repair with suture tape augmentation resulted in overconstraint of the elbow joint compared with the native ligament biomechanics. CLINICAL RELEVANCE: As more long-term outcome data from UCL repair with suture tape augmentation emerge, there will be wider implementation with various techniques to tension the suture tape. Examining the potential biomechanical sequelae of the UCL repair construct applied under maximal tension will help further refine recommendations for surgeons who utilize this technique for UCL repair.

Rehabilitation of the painful elbow.

Although lateral elbow pain and medial ulnar collateral ligament injury are common musculoskeletal pathologies in overhead athletes, the evidence supporting specific interventions for managing these conditions is scarce. Management of these conditions has been guided mostly by expert opinion rather than empirical evidence, yet the lack of comparative data in the literature has not negatively affected return-to-play rates following surgery. However, an understanding of what is known regarding unimodal and multimodal treatments for lateral elbow pain and medial ulnar collateral ligament injury is needed for clinicians to select evidence-based treatment pathways and highlight what is not known to develop future high-quality investigations.

Similar return to sport between double cortical button and docking techniques for ulnar collateral ligament reconstruction in baseball players.

BACKGROUND AND HYPOTHESIS: A double cortical button technique for ulnar collateral ligament reconstruction (UCLR) has advantages including significant control over graft tensioning, less concern about graft length, and minimized risk of bone tunnel fracture compared with traditional UCLR techniques. This double cortical button technique was recently found to be noninferior in mechanical performance to the traditional docking technique regarding joint strength, joint stiffness, and graft strain. However, clinical outcomes have not been compared between these UCLR techniques. Therefore, the purpose of this study was to determine whether baseball players who underwent UCLR with a double cortical button (double button) technique have similar return-to-sport (RTS) outcomes to baseball players who underwent UCLR with the traditional docking (docking) technique. MATERIALS AND METHODS: Baseball players who underwent primary UCLR from 2011 to 2020 across 2 institutions were identified. Included patients were contacted to complete a follow-up survey evaluating reoperations, RTS, and functional outcome scores. Functional outcome surveys include the Kerlan-Jobe Orthopaedic Clinic score, the Conway-Jobe score, the Andrews-Timmerman elbow score, and the Single Assessment Numeric Evaluation score. RESULTS: Overall, 78 male baseball players (age: 18.9 ± 2.4 years) with an average follow-up of 3.1 ± 2.4 years were evaluated, with 73 of the players being baseball pitchers. Players in the double button group more frequently received palmaris longus autografts (78% vs. 30%) and less frequently received gracilis autografts (22% vs. 58%) compared with players in the docking group (P = .001); however, all other demographic factors were similar between the groups. All players in the double button group were able to RTS in 11.1 ± 2.6 months, whereas 96% of players in the docking group were able to RTS in 13.5 ± 3.4 months (P > .05). All postoperative outcomes and patient-reported outcomes were statistically similar between the groups and remained similar after isolating pitchers only and after separating partial-thickness from full-thickness UCL tears (all P > .05). CONCLUSION: RTS and other postoperative outcomes may be similar between baseball players who underwent UCLR with the double button technique and the docking technique. Although future research may be necessary to strengthen clinical recommendations, these findings provide the first clinical outcomes in light of a recent cadaveric study finding similar elbow strength, joint stiffness, and graft strain compared with the docking technique.