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).

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.

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.

Thumb Metacarpophalangeal Joint Kinematics and Elongation of the Ulnar Collateral Ligament.

PURPOSE: The purpose of the study was to determine if the sphericity of the thumb metacarpophalangeal (MCP) joint influences the joint's rotational axis (RA) and elongation patterns of the ulnar collateral ligament (UCL). METHODS: Ulnar collateral ligament origins and attachments of 28 fresh-frozen cadaveric thumbs were marked with a radiopaque marker. Lateral radiographs were obtained in neutral and 20°, 40°, and 60° of flexion. The dorsal and palmar joint gap and the length of four different UCL portions were digitally measured in all flexion states. The RA was determined by the intersection of the midshaft axis of the proximal phalanx in neutral and flexion states. Sphericity of the MCP joint was assessed using morphometric parameters. Joints were grouped as round or flat. Differences in all measured parameters between groups were analyzed. RESULTS: During flexion, the dorsal joint gap increased by 322% in flat joints and 163% in round joints. The palmar joint gap decreased to 45% in flat joints and to 87% in round joints. The RA was at 29% of metacarpal height and 96% of metacarpal length in flat joints and at 40% of height and 86% of length in round joints. Maximum UCL elongation (111%) was noted at 40° flexion in the dorsal proper UCL in flat joints and at 60° flexion in the accessory UCL (117%) in round joints. CONCLUSIONS: In flat MCP joints, the RA is more dorsal and distal in the metacarpal head compared to round joints, resulting in a hinged flexion motion. Elongation of the UCL is highest at end flexion in round joints and highest at midflexion in flat joints. CLINICAL RELEVANCE: The different kinematics of flat and round MCP joints may contribute to the understanding of the pathophysiology of UCL ruptures. The propensity of this injury and the position in which they occur may be affected by the MCP joint morphology.

Graft choice and techniques used in elbow ulnar collateral ligament reconstruction over the last 20 years: a systematic review and meta-analysis.

BACKGROUND: Elbow medial ulnar collateral ligament (mUCL) injuries have become increasingly common, leading to a higher number of mUCL reconstructions (UCLR). Various techniques and graft choices have been reported. The purpose of this study was to evaluate the prevalence of each available graft choice, the surgical techniques most utilized, and the reported complications associated with each surgical method. METHODS: A systematic review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analysesguidelines. We queried PubMed/MEDLINE, Embase, Web of Science, and Cochrane databases to identify all articles that included UCLR between January 2002 and October 2022. We included all studies that referenced UCLR graft choice, surgical technique, and/or ulnar nerve transposition. Studies were evaluated in a narrative fashion to assess demographics and report current trends in utilization and complications of UCLR as they pertain to graft choice and surgical techniques over the past 20 years. Where possible, we stratified based on graft and technique. RESULTS: Forty-seven articles were included, reporting on 6671 elbows. The cohort was 98% male, had a weighted mean age of 21 years and follow-up of 53 months. There were 6146 UCLRs (92%) performed with an autograft and 152 (2.3%) that utilized an allograft, while 373 (5.6%) were from mixed cohorts of autograft and allograft. Palmaris longus autograft was the most utilized mUCL graft choice (64%). The most utilized surgical configuration was the figure-of-8 (68%). Specifically, the most common techniques were the modified Jobe technique (37%), followed by American Sports Medicine Institute (ASMI) (22%), and the docking (22%) technique. A concomitant ulnar nerve transposition was performed in 44% of all patients, with 1.9% of these patients experiencing persistent ulnar nerve symptoms after ulnar nerve transposition. Of the total cohort, 14% experienced postoperative ulnar neuritis with no prior preoperative ulnar nerve symptoms. Further, meta-analysis revealed a significantly greater revision rate with the use of allografts compared to autograft and mixed cohorts (2.6% vs. 1.8% and 1.9%, P = .003). CONCLUSIONS: Most surgeons performed UCLR with palmaris autograft utilizing a figure-of-8 graft configuration, specifically with the modified Jobe technique. The overall rate of allograft use was 2.3%, much lower than expected. The revision rate for UCLR with allograft appears to be greater compared to UCLR with autograft, although this may be secondary to limited allograft literature.

Characterizing focal muscle signal on MRI in flexor-pronator muscles' status post ulnar collateral ligament reconstruction.

OBJECTIVE: Focal high signal is commonly seen about the flexor pronator mass on MRI in some patients after ulnar collateral ligament (UCL) reconstruction of the elbow. The etiology of this high signal is unclear and not described in literature. The hypothesis is that the edema we see on post-operative MRI is related to palmaris longus graft harvest rather than secondary to other causes of muscle edema such as denervation or muscle strain. METHODS AND MATERIALS: An IRB waiver-approved, retrospective search of our radiology database was conducted using the keywords "ucl," "elbow," and "reconstruction" between 1/01/2012 and 1/01/2022, with search parameters set as MRI for exam type. The images were reviewed to evaluate for high signal at the flexor pronator mass by a junior and a senior musculoskeletal radiologist. The surgical notes were then reviewed in electronic medical record system to see which graft was used for the UCL reconstruction. RESULTS: The cohort comprised of 33 patients (1 female/32males, 14-51 years old) who had undergone UCL reconstructions. Four patients were excluded from the study secondary to the surgical note not specifying which graft was used. The surgical and imaging dates were also recorded with the largest time gap of 7 years between the surgery and imaging. Seventeen of the 29 patients had palmaris longus harvested from the ipsilateral arm, 1 patient had palmaris longus harvested from the contralateral arm, 2 patients had an internal brace, and 9 patients had a hamstring graft. Seventeen out of 17 (100%) patients with ipsilateral palmaris longus graft demonstrated focal edema at the flexor pronator mass while 0/12 of the patients without the palmaris longus graft showed the focal edema seen by its counterparts. CONCLUSION: High signal which is commonly seen at the flexor pronator mass in patient status most UCL reconstruction of the elbow is secondary to the palmaris longus harvest rather than other etiologies such as muscle strain, retear, or trauma.

Elbow Ulnar Collateral Ligament Tears in 2023: Evaluation and Management.

The ulnar collateral ligament, also called the medial collateral ligament of the elbow, is the primary stabilizer against valgus loads. This ligament can be traumatically torn, such as in an elbow dislocation, or can tear through attritional damage with overhead sports. Although baseball pitching is the most common contributor, these injuries also occur with volleyball, gymnastics, and javelin throwing. Patients most commonly report a history of medial elbow pain with associated loss of command, control, and throw velocity. The ulnar nerve lies directly superficial to the posterior band of the ulnar collateral ligament and ulnar neuritis is commonly associated with ulnar collateral ligament pathology. Nonsurgical treatment, including rest from activity, flexor-pronator strengthening, and possible platelet-rich plasma injections, can be considered for partial-thickness tears. Surgical treatment can be considered for patients in whom nonsurgical treatment fails and full-thickness tears. Historically, surgical treatment involved reconstruction of the ligament with a tendon graft. Ipsilateral palmaris longus autograft has been the most commonly used graft, but contralateral palmaris, autograft hamstring tendons, and allograft tendon have also been used. This procedure has a high rate of return to play and a low complication rate, but most athletes require 12 to 18 months to fully return. More recently, repair of the ligament, with the addition of a biologic ingrowth ligament augmentation suture, has demonstrated similarly high rates of return to play and low complication rates, with a full return to play in 6 months.

Surgical Interventions for Chronic Ulnar Collateral Ligament Injuries of the Thumb: A Systematic Review.

Background: There is no consensus for the appropriate surgical management of symptomatic chronic ulnar collateral ligament (UCL) injuries of the thumb. The aim of this study is to systematically review the treatment of chronic thumb metacarpophalangeal (MCP) joint UCL injuries to determine the optimal approach to treatment. Methods: A systematic review of PubMed, Medline, Embase and ePub Ahead of Print was performed in accordance with Preferred Reporting of Items in Systematic Review and Meta-Analysis (PRISMA) guidelines. Results: Data from 11 studies using various surgical techniques in 245 thumbs were heterogenous and meta-analysis of results not possible. These data were qualitatively assessed. Direct repair, reconstruction with free tendon grafts and arthrodesis all demonstrated favourable outcomes with patient-reported outcome measures (PROMs). Conclusions: Direct repair can be safely performed more than 2 months following injury. Arthrodesis may be considered in heavy manual labourers or those with osteoarthrosis. Tendon grafting is safe, yet the optimal type and configuration are yet to be determined for reconstructive methods. Level of Evidence: Level III (Therapeutic).

Posterolateral Rotatory Instability Develops Following the Modified Kocher Approach and Does Not Resolve Following Interval Repair.

BACKGROUND: The modified Kocher and extensor digitorum communis (EDC)-splitting intervals are commonly utilized to approach the lateral elbow. Iatrogenic injury to the lateral ulnar collateral ligament may result in posterolateral rotatory instability (PLRI). in the present cadaveric study, we (1) evaluated lateral elbow stability following the use of these approaches and (2) assessed the accuracy of static lateral elbow radiographs as a diagnostic tool for PLRI. METHODS: Ten matched-pair cadaveric upper-extremity specimens (n = 20) were randomly assigned to Kocher or EDC-splitting approaches. Specimens underwent evaluation pre-dissection, post-dissection, and following repair of the surgical interval. Clinical evaluation of lateral elbow stability was performed with the lateral pivot-shift maneuver. Radiographic radiocapitellar displacement was evaluated with the fully extended hanging arm test and on lateral elbow 30° flexion radiographs. Paired Wilcoxon signed-rank tests with Bonferroni correction were utilized to compare groups. RESULTS: All Kocher group specimens (10 of 10) developed PLRI on the pivot-shift maneuver following dissection. No EDC-splitting group specimens (0 of 10) developed instability with pivot-shift testing. The fully extended hanging arm test showed no difference in radiocapitellar displacement between groups (p > 0.008). Lateral elbow 30° flexion radiographs in the Kocher group showed an increased radiocapitellar displacement difference (mean, 8.46 mm) following dissection compared with the pre-dissection baseline (p < 0.008). Following repair of the Kocher interval, the radiocapitellar displacement (mean, 6.43 mm) remained greater than pre-dissection (mean, 2.26 mm; p < 0.008). In the EDC-splitting group, no differences were detected in radiocapitellar displacement on lateral elbow radiographs with either the fully extended hanging arm or lateral elbow 30° flexion positions. CONCLUSIONS: The Kocher approach produced PLRI that did not return to baseline conditions following repair of the surgical interval. The EDC-splitting approach did not cause elbow instability clinically or radiographically. The hanging arm test was not reliable for the detection of PLRI. CLINICAL RELEVANCE: The Kocher interval for lateral elbow exposure results in iatrogenic PLRI that is not detectable on the hanging arm test and that does not return to baseline stability following repair of the surgical interval.

Implant-free anatomical reconstruction of thumb metacarpophalangeal joint chronic ulnar collateral ligament injuries.

A technique is described to treat chronic instability of the metacarpophalangeal joint of the thumb caused by rupture of the ulnar collateral ligament using a palmaris longus tendon graft without implants. Good results were obtained in eight patients.

Patient-Reported Outcomes and Function After Surgical Repair of the Ulnar Collateral Ligament of the Thumb.

PURPOSE: The purpose of this study was to report prospectively collected patient-reported outcomes of patients who underwent open thumb ulnar collateral ligament (UCL) repair and to find risk factors associated with poor patient-reported outcomes. METHODS: Patients undergoing open surgical repair for a complete thumb UCL rupture were included between December 2011 and February 2021. Michigan Hand Outcomes Questionnaire (MHQ) total scores at baseline were compared to MHQ total scores at three and 12 months after surgery. Associations between the 12-month MHQ total score and several variables (i.e., sex, injury to surgery time, K-wire immobilization) were analyzed. RESULTS: Seventy-six patients were included. From baseline to three and 12 months after surgery, patients improved significantly with a mean MHQ total score of 65 (standard deviation [SD] 15) to 78 (SD 14) and 87 (SD 12), respectively. We did not find any differences in outcomes between patients who underwent surgery in the acute (<3 weeks) setting compared to a delayed setting (<6 months). CONCLUSIONS: We found that patient-reported outcomes improve significantly at three and 12 months after open surgical repair of the thumb UCL compared to baseline. We did not find an association between injury to surgery time and lower MHQ total scores. This suggests that acute repair for full-thickness UCL tears might not always be necessary. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic II.

Elbow Ulnar Collateral Ligament Tears: A Modified Consensus Statement.

PURPOSE: To establish consensus statements on the treatment of ulnar collateral ligament (UCL) injuries and to investigate whether consensus on these distinct topics could be reached. METHODS: A modified consensus technique was conducted among 26 elbow surgeons and 3 physical therapists/athletic trainers. Strong consensus was defined as 90% to 99% agreement. RESULTS: Of the 19 total questions and consensus statements 4 achieved unanimous consensus, 13 achieved strong consensus, and 2 did not achieve consensus. CONCLUSIONS: There was unanimous agreement that the risk factors include overuse, high velocity, poor mechanics, and previous injury. There was unanimous agreement that advanced imaging in the form of either magnetic resonance imaging or magnetic resonance arthroscopy should be performed in a patient presenting with suspected/known UCL tear that plans to continue to play an overhead sport, or if the imaging study could change the management of the patient. There was unanimous agreement regarding lack of evidence for the use of orthobiologics in the treatment of UCL tears as well as the areas pitchers should focus on when attempting a course of nonoperative management. The statements that reached unanimous agreement for operative management were regarding operative indications and contraindications for UCL tears, prognostic factors that should be taken into consideration in when performing UCL surgery, how to deal with the flexor-pronator mass during UCL surgery, and use of an internal brace with UCL repairs. Statements that reached unanimous agreement for return to sport (RTS) were regarding portions of the physical examination should be considered when determining whether to allow a player to RTS; unclear how velocity, accuracy, and spin rate should be factored into the decision of when players can RTS and sports psychology testing should be used to determine whether a player is ready to RTS. LEVEL OF EVIDENCE: V, expert opinion.

2022 Bernard Morrey Award: the elbow ulnar collateral ligament complex demonstrates region specific stretching and recovery characteristics with valgus loading.

BACKGROUND: The objective of this study was to quantify the valgus laxity and strain of the elbow ulnar collateral ligament (UCL) complex after repeated valgus stretching and subsequent recovery. Understanding these changes may have important implications in improving strategies for injury prevention and treatment. The hypothesis was that the UCL complex will demonstrate a permanent increase in valgus laxity and region-specific increase in strain as well as region-specific recovery characteristics. METHODS: Ten cadaveric elbows (7M, 3F, 61.7 ± 2.7 years) were used. Valgus angle and strain of the anterior and posterior bands of the anterior bundle and the posterior bundle were measured at 1 Nm, 2.5 Nm, 5 Nm, 7.5 Nm, and 10 Nm of valgus torque at 70° of flexion for: (1) intact UCL, (2) stretched UCL, and (3) rested UCL. To stretch the UCL, elbows were cycled with increasing valgus torque at 70° of flexion (10 Nm-20 Nm in 1 Nm increments) until the valgus angle increased 8° from the intact valgus angle measured at 1Nm. This position was held for 30 minutes. Specimens were then unloaded and rested for 2 hours. Linear mixed effects model with Tukey's post hoc test was used for statistical analysis. RESULTS: Stretching significantly increased valgus angle compared to the intact condition 3.2° ± 0.2° (P < .001). Strains of both the anterior and posterior bands of the anterior bundle were significantly increased from intact by 2.8% ± 0.9% (P = .015) and 3.1% ± 0.9% (P = .018), respectively at 10 Nm. Strain in the distal segment of the anterior band was significantly higher than the proximal segment with loads of 5 Nm and higher (P < .030). After resting, the valgus angle significantly decreased from the stretched condition by 1.0° ± 0.1° (P < .001) but failed to recover to intact levels (P < .004). After resting, the posterior band had a significantly increased strain compared to the intact state of 2.6% ± 1.4% (P = .049) while the anterior band was not significantly different from intact. CONCLUSION: After repeated valgus loading and subsequent resting, the UCL complex demonstrated permanent stretching with some recovery but not to intact levels. The anterior band demonstrated increased strain in the distal segment compared to the proximal segment with valgus loading. The anterior band was able to recover to strain levels similar to intact after resting, while the posterior band did not.

Can we do it faster? accelerated rehabilitation following thumb ulnar collateral ligament repair with suture tape augmentation.

Ulnar Collateral Ligament (UCL) injuries are the most common thumb metacarpophalangeal joint ligamentinjury. Rehabilitation protocols traditionally permit return to sport at 12 weeks post-surgery. In this article, we propose anacellerated rehabilitation protocol permitting return to sport at 5-6 post-surgery in the recreational athlete.

Locking suture repair versus ligament augmentation-a biomechanical study regarding the treatment of acute lateral collateral ligament injuries of the elbow.

BACKGROUND: Lateral collateral ligament (LCL) tears are frequently observed in fractures and dislocations of the elbow. Recent biomechanical evidence suggests that additional ligament augmentation may improve repair stability. The aim of this biomechanical in-vitro study was to compare the resistance of a locking suture repair of the LCL with a ligament augmentation technique. MATERIAL AND METHODS: Eight fresh frozen cadaveric elbows were evaluated for stability against varus/posterolateral rotatory forces (3 Nm). A strain gauge (µm/m; negative values) was placed at the origin and insertion of the lateral ulnar collateral ligament (LUCL) and cyclic loading was performed for 1000 cycles. We analyzed three distinct scenarios: (A) native LCL, (B) locking transosseou suture repair of the LCL, (C) simple LCL repair with additional ligament augmentation of the LUCL. RESULTS: The mean measured strain was - 416.1 µm/m (A), - 618 µm/m (B) and - 288.5 µm/m (C) with the elbow flexion at 90°; the strain was significantly higher in scenario B compared to C (p = .01). During the cyclic load (1000) the mean measured strain was - 523.1 µm/m (B) and - 226.3 µm/m (C) with the elbow flexion at 60°; the strain was significantly higher in scenario B compared to C (p = .01). No significant difference between the first and the last cycles was observed (p = .09; p = .07). One failure of the LCL repair was observed after 1000 cycles; none of the ligament augmentations failed. CONCLUSION: Ligament augmentation (C) provides higher resistance compared to the native LCL (A) and to the locking suture repair technique (B). Both techniques, however, hold up during 1000 cycles. While ligament augmentation might enhance the primary stability of the repair, future clinical studies have to show whether this increase in resistance leads to negative effects like higher rates of posttraumatic elbow stiffness. LEVEL OF EVIDENCE: Basic science study, biomechanics.

Lateral Ulnar Collateral Ligament Repair With Suture-Tape Augmentation for Traumatic Elbow Instability.

PURPOSE: Ligament repair with suture-tape augmentation has been used in the operative treatment of joint instability and may have advantages with respect to early motion and stability. The purpose of this investigation was to describe the clinical results of traumatic elbow instability treated with lateral ulnar collateral ligament repair with suture-tape augmentation. METHODS: All cases of acute and chronic elbow instability treated surgically between 2018 and 2020 were included if they underwent ligament repair with suture-tape augmentation of the lateral ulnar collateral ligament as part of the procedure. Cases with <6 months of follow-up were excluded. A manual chart review was performed to record patient demographics as well as injury and surgery characteristics. Radiographic outcomes, range of motion, and patient-reported outcome measures, including the visual analog pain scale and Disabilities of the Arm, Shoulder, and Hand, were recorded. Range of motion measurements were recorded at the end of the clinical follow-up, as were surgical complications. RESULTS: Eighteen cases were included with a mean follow-up of 20 months. Five (28%) cases involved a high-energy mechanism, and 11 (62%) cases involved terrible triad fracture dislocations. The mean Disabilities of the Arm, Shoulder, and Hand questionnaire and visual analog pain scale scores were 17 and 2, respectively. The mean flexion-extension arc was 124°, and 2 (11%) cases had <100° flexion-extension arc. There were 2 (11%) postoperative complications, and both cases had postoperative instability requiring reoperation. We observed no cases of capitellar erosion from the suture-tape material. CONCLUSIONS: For complex elbow instability, ligament repair with suture-tape augmentation of the lateral ulnar collateral ligament results in acceptable functional outcomes and a reoperation rate comparable with other joint stabilization procedures. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Finite Element Analysis of Elbow Joint Stability by Different Flexion Angles of the Annular Ligament.

OBJECTIVE: The injury of the annular ligament can change the stress distribution and affect the stability of the elbow joint, but its biomechanical mechanism is unclear. The present study investigated the biomechanical effects of different flexion angles of the annular ligament on elbow joint stability. METHODS: A cartilage and ligament model was constructed using SolidWorks software according to the magnetic resonance imaging results to simulate the annular ligament during normal, loosened, and ruptured conditions at different buckling angles (0°, 30°, 60°, 90°, and 120°). The fixed muscle strengths were 40 N (F1), 20 N (F2), 20 N (F3), 20 N (F4), and 20 N (F5) for the triceps, biceps, and brachial tendons and the base of the medial collateral ligament and lateral collateral ligament. The different elbow three-dimensional (3D) finite element models were imported into ABAQUS software to calculate and analyze the load, contact area, contact stress, and stress of the medial collateral ligament of the olecranon cartilage. RESULTS: The results showed that the stress value of olecranon cartilage increased under different conditions (normal, loosened, and ruptured annular ligament) with elbow extension, and the maximum stress value of olecranon cartilage was 2.91 ± 0.24 MPa when the annular ligament was ruptured. The maximum contact area of olecranon cartilage was 254 mm2 with normal annular ligament when the elbow joint was flexed to 30°, while the maximum contact area of loosened and ruptured annular ligament was 283 and 312 mm2 at 60° of elbow flexion, and then decreased gradually. The maximum stress of the medial collateral ligament was 6.52 ± 0.23, 11.51 ± 0.78, and 18.74 ± 0.94 MPa under the different conditions, respectively. CONCLUSION: When the annular ligament ruptures, it should be reconstructed as much as possible to avoid the elevation of stress on the surface of the medial collateral ligament of the elbow and the annular cartilage, which may cause clinical symptoms.

Ultrasonography: an interesting imaging method for ligament assessment during the acute phase of closed elbow injuries.

PURPOSE: To evaluate whether ultrasonography can be used to explore the medial and lateral ligament structures during the acute phase of a closed elbow injury. METHODS: A single-center, prospective study performed between December 2019 and June 2020, including patients who suffered a radial head fracture or elbow dislocation. Two radiologists did a blinded analysis using ultrasonography of visibility, injury grade, and presence of bone avulsion for the radial collateral ligament (RCL), lateral ulnar collateral ligament (LUCL), annular ligament (AL), and anterior (MCLant) and posterior bundles (MCLpost) of the medial collateral ligament. The inter-rater agreement was calculated. The ultrasonography findings were compared with the intraoperative findings in the patients who subsequently underwent surgery. RESULTS: Forty patients were included (28 radial head fractures and 12 elbow dislocations). The inter-rater agreement was strong for all the study parameters (kappa between 0.65 and 1), except for the visibility of the LUCL (kappa 0.52) and the visibility and appearance of the MCLpost (kappa 0.54 and 0.47, respectively). The injured ligaments were thicker than their contralateral counterparts (p < 0.05). In the 10 patients who underwent surgery, the radiological-surgical correlation was 100% for the RCL and medial ligaments and 70% for the LUCL. CONCLUSION: Ultrasonography is a reproducible examination that can be used to assess the damage to elbow ligaments during the acute phase following an injury. This examination could be incorporated into the exploration protocol for elbow injuries during the preoperative assessment and to adapt the treatment.

Collateral Ligament Ruptures of the Thumb Metacarpophalangeal Joint A Review of 500 Surgical Cases.

A retrospective review was conducted of 500 consecutive patients who underwent surgery for complete collateral ligament ruptures of their thumb metacarpophalangeal (MP) joints comprising 362 ulnar collateral and 138 radial collateral ligaments. Complete rupture was confirmed in all cases at surgery. When surgery was carried out within 3 weeks of the injury, reinsertion of the ligament was pos- sible in 98% of cases. When surgery was performed after 3 weeks, reinsertion of the ligament was possible in 45% of ulnar and 68% of radial injuries. Reconstruction utilizing a free tendon graft was required for the other cases. All patients who had surgery within 3 weeks of their injuries regained stable, pain free thumbs. Surgery was less suc- cessful in patients who had surgery after 3 weeks and the failure rate was 5%. Surgery within 3 weeks of the injury permitted re-insertion of the ligament in almost all cases. We propose that avulsions treated within that period be referred to as "acute" injuries and those treated later as "chronic." Treatment of acute injuries is preferred because they rarely require reconstruction, and the results were better than when surgery was performed for chronic injuries. Repair of thumb MP collateral ligaments is predictably possible within 3 weeks of injury but less likely if surgery is delayed after that time period.

Elbow Ulnar Collateral Ligament Injuries in Overhead Athletes: An Infographic Summary.

Ulnar collateral ligament (UCL) injuries of the elbow are common in throwing athletes. Given that the UCL's primary function is to provide valgus stability during the deceleration phase of throwing, injury to the UCL will render throwing difficult to nearly impossible.15 Injuries will occur more so in the sports of baseball, softball, and javlineers participating in track and field.5,10,14 Data has indicated that valgus torque reaches 64 N-m and proximal forces as high as 1000 N to prevent elbow distraction. Further, angular velocity across elbow may reach 1900-2480 degrees/second.6,8 Imaging modalities that have the greatest accuracy for diagnosis include magnetic resonance imaging (MRI), MRI-arthrogram, and stress ultrasonography.2,3,11,12 Treatment of UCL injury depends on multiple factors. These include if the injury is a partial tear or complete tear and the location (distal versus proximal) of the partial tear.7 Further, complete tears, as well as partial distal tears, are more likely to undergo surgical intervention.1,13 Treatment decision-making is primarily dependent on following factors: location, severity, if the patient is a throwing athlete, and if the patient is in his or her last year of his/her throwing career due to the length of the rehabilitation process if surgery is pursued.15 Return-to-play success rates when treated conservatively vary from anywhere from 42% to 100%. Conservative treatment includes rest, rehabilitation, platelet-rich plasma injections, and a throwing program.4 Surgical treatment has evolved significantly with various reconstructive techniques and (when indicated) surgical repair with internal bracing. Return-to-play rates are high, ranging from 80% to 95% with low complication rates, but rehabilitation for reconstruction can range from 12-18 months or longer. Therefore, patients must be made aware of the commitment to the rehabilitation process if electing to undergo surgical reconstruction.9.