Rehabilitation Protocols in Elbow Medial Ulnar Collateral Ligament Injuries: A Systematic Review of Articles Published in the Last 20 Years.

CONTEXT: Elbow medial ulnar collateral ligament (UCL) injuries have become increasingly common in athletes. Despite this, rehabilitation protocols appear to vary drastically, which may explain the clinical equipoise regarding optimal management. OBJECTIVE: This systematic review reports rehabilitation characteristics reported after UCL injuries and compares reported outcomes based on early versus delayed rehabilitation. DATA SOURCES: Our search utilized PubMed/MEDLINE, Embase, Web of Science, and Cochrane to identify all articles on UCL rehabilitation published between January 1, 2002 and October 1, 2022. STUDY SELECTION: Studies in English with ≥5 patients that reported rehabilitation protocols for UCL injuries were evaluated. STUDY DESIGN: Systematic review. LEVEL OF EVIDENCE: Level 4. DATA EXTRACTION: Data included sample characteristics, time to achieve physical therapy milestones, outcome scores, and return-to-play (RTP) rate and timing. RESULTS: Our review included 105 articles with a total of 15,928 elbows (98% male; weighted mean age, 23 years; follow-up, 47 months), with 15,077 treated operatively and 851 treated nonoperatively. The weighted mean time patients spent adhering to nonweightbearing status was 42 days. The mean time until patients were given clearance for active range of motion (ROM) 15 days, full ROM 40 days, and elbow strengthening exercises 32 days. The mean time until all restrictions were lifted was 309 days. The mean time to begin a throwing program was 120 days. Across all rehabilitation characteristics, protocols for patients undergoing nonoperative management started patients on rehabilitation earlier. After UCL reconstruction, earlier active ROM (≤14 days), elbow strengthening (≤30 days), no restrictions (≤180 days), and throwing (≤120 days) postoperatively led to earlier RTP without a negative effect on functional outcome scores. CONCLUSION: Current literature provides a spectrum of protocols for elbow UCL rehabilitation, regardless of management. Nonoperative patients began ROM activities, strengthening, and throwing programs sooner than operative patients, and earlier milestones led to earlier RTP.

Comparison of Pain Scores and Functional Outcomes of Patients Undergoing Arthroscopic Hip Labral Repair and Concomitant Capsular Repair or Plication Versus No Closure.

Background: The need for capsular closure during arthroscopic hip labral repair is debated. Purpose: To compare pain and functional outcomes in patients undergoing arthroscopic hip labral repair with concomitant repair or plication of the capsule versus no closure. Study Design: Cohort study. Methods: Outcomes were compared between patients undergoing arthroscopic hip labral repair with concomitant repair or plication of the capsule versus no closure at up to 2 years postoperatively and with stratification by age and sex. Patients with lateral center-edge angle <20°, a history of instability, a history of prior arthroscopic surgery in the ipsilateral hip, or a history of labral debridement only were excluded. Subanalysis was performed between patients undergoing no capsular closure who were propensity score matched 1:1 with patients undergoing repair or plication based on age, sex, and preoperative Modified Harris Hip Score (MHHS). We compared patients who underwent T-capsulotomy with concomitant capsular closure matched 1:5 with patients who underwent an interportal capsulotomy with concomitant capsular repair based on age, sex, and preoperative MHHS. Results: Patients undergoing capsular closure (n = 1069), compared with the no-closure group (n = 230), were more often female (68.6% vs 53.0%, respectively; P < .001), were younger (36.4 ± 13.3 vs 47.9 ± 14.7 years; P < .001), and had superior MHHS scores at 2 years postoperatively (85.8 ± 14.5 vs 81.8 ± 18.4, respectively; P = .020). In the matched analysis, no difference was found in outcome measures between patients in the capsular closure group (n = 215) and the no-closure group (n = 215) at any follow-up timepoint. No significant difference was seen between the 2 closure techniques at any follow-up timepoint. Patients with closure of the capsule achieved the minimal clinically important difference (MCID) and the patient acceptable symptom state (PASS) for the 1-year MHHS at a similar rate as those without closure (MCID, 50.3% vs 44.9%, P = .288; PASS, 56.8% vs 51.1%, P = .287, respectively). Patients with T-capsulotomy achieved the MCID and the PASS for the 1-year MHHS at a similar rate compared with those with interportal capsulotomy (MCID, 50.1% vs 44.9%, P = .531; PASS, 65.7% vs 61.2%, P = .518, respectively). Conclusion: When sex, age, and preoperative MHHS were controlled, capsular closure and no capsular closure after arthroscopic hip labral repair were associated with similar pain and functional outcomes for patients up to 2 years postoperatively.

Phased nanopore assembly with Shasta and modular graph phasing with GFAse.

Reference-free genome phasing is vital for understanding allele inheritance and the impact of single-molecule DNA variation on phenotypes. To achieve thorough phasing across homozygous or repetitive regions of the genome, long-read sequencing technologies are often used to perform phased de novo assembly. As a step toward reducing the cost and complexity of this type of analysis, we describe new methods for accurately phasing Oxford Nanopore Technologies (ONT) sequence data with the Shasta genome assembler and a modular tool for extending phasing to the chromosome scale called GFAse. We test using new variants of ONT PromethION sequencing, including those using proximity ligation, and show that newer, higher accuracy ONT reads substantially improve assembly quality.

Initial Assessment and Management of Select Musculoskeletal Injuries: A Team Physician Consensus Statement.

ABSTRACT: Musculoskeletal injuries occur frequently in sport during practice, training, and competition. Injury assessment and management are common responsibilities for the team physician. Initial Assessment and Management of Musculoskeletal Injury-A Team Physician Consensus Statement is title 23 in a series of annual consensus documents written for the practicing team physician. This statement was developed by the Team Physician Consensus Conference, an annual project-based alliance of six major professional associations. The goal of this document is to help the team physician improve the care and treatment of the athlete by understanding the initial assessment and management of selected musculoskeletal injuries.

Initial Assessment and Management of Select Musculoskeletal Injuries: A Team Physician Consensus Statement.

ABSTRACT: Musculoskeletal injuries occur frequently in sport during practice, training, and competition. Injury assessment and management are common responsibilities for the team physician. Initial Assessment and Management of Musculoskeletal Injury-A Team Physician Consensus Statement is title 23 in a series of annual consensus documents written for the practicing team physician. This statement was developed by the Team Physician Consensus Conference, an annual project-based alliance of six major professional associations. The goal of this document is to help the team physician improve the care and treatment of the athlete by understanding the initial assessment and management of selected musculoskeletal injuries.

Arthroscopy and Microfracture for Osteochondritis Dissecans of the Capitellum in Adolescent Athletes Shows Favorable Return to Sport: A Systematic Review.

PURPOSE: To assess return to sport (RTS) in the high-risk young athlete population with capitellar osteochondritis dissecans (OCD) undergoing arthroscopic microfracture (MFX) with or without debridement as well as associated indications, clinical outcomes, radiographic outcomes, and complications. METHODS: A literature search of all published literature in the English language from PubMed, EMBASE, Scopus, and Cochrane from database inception to April 4, 2022, was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Included studies presented demographics and outcomes for adolescent (<21 years old) patients diagnosed with capitellar OCD who underwent arthroscopic MFX (or drilling/subchondral drilling) or MFX (or drilling/subchondral drilling) with debridement (or loose body removal/chondroplasty). Studies containing multiple surgical techniques that did not distinguish characteristics and outcomes of individual patients by surgical technique were excluded. Additionally, if there was overlap in patient populations between 2 studies, the study with less outcome data was excluded. Extracted data included study properties, patient demographics, lesion characteristics, surgery details, and patient outcomes, including range of motion, outcome scores, and RTS rates. Bias was assessed via the Methodological Index for Non-Randomized Studies (MINORS). RESULTS: Nine studies of 136 patients and 138 elbows met criteria. Included articles were published between 2005 and 2020 with MINORS scores of 8 to 14 (50% to 88%). The age ranged from 12.7 to 15.7 years with most patients being involved in baseball or gymnastics and a rate of dominant elbow involvement of 55% to 100%. Patient follow-up ranged from 16 to 138 months. All 9 studies reported RTS, ranging from 65% to 100%. Six of these studies categorized the level to which the patient returned, with patients RTS at the same level of competition ranging from 60% to 100%. Six studies reported complications, with a range rate of 0% to 43%; there were a total of 10 complications, 7 of which required reoperations. CONCLUSIONS: Arthroscopic MFX with or without arthroscopic debridement is a safe and effective treatment for OCD lesions of the capitellum in young, athletic patients. Included studies reported improved clinical, radiographic, and patient-reported outcomes. Aside from 1 study reporting an RTS of 65%, the rate of RTS ranged from 86% to 100%. The percentage of patients returning to sport at the same level of competition ranged from 60% to 100% with a time to RTS ranging from 4.1 to 5 months. A single study reported a complication rate of 43%, while remaining studies reported complication rates between 0% and 19%, with loose bodies being the most common complication requiring reoperation. Follow-up ranged from 16 to 138 months. LEVEL OF EVIDENCE: Level IV, systematic review of Level IV studies.

Diversity Within the Field of Orthopedic Sports Medicine: A Systematic Review.

BACKGROUND: Orthopedic surgery is among the least diverse specialties in medicine. This systematic review analyzes gender, racial, and ethnic diversity within orthopedic sports medicine and aims to raise awareness and provide guidance for future strategies that support underrepresented minorities in medicine (URMs) and women in joining the orthopedic sports medicine workforce. We hypothesize that at all tiers of training, there is a lack of gender, racial, and ethnic parity in academic rank, leadership positions, and research productivity. METHODS: A search of all published literature in the English language from PubMed, Embase, Cochrane, and Scopus databases, between January 1, 2010, and August 18, 2023, was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Included studies presented demographics regarding diversity within orthopedic sports medicine and provided trends in applicants, attendings, leadership, and/or research. Bias was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) study checklist. RESULTS: Thirteen studies published between 2016 and 2023 with STROBE scores 15.5 to 21.5 (70.5% to 97.7%) met criteria, and pertinent data were extracted. The percent of female orthopedic sports medicine surgeons from 2010 to 2019 increased from 5% (n = 138) to 6% (n = 206) with a compound annual growth rate of 0.2% (r2 = 0.97; p < 0.001). Females and URMs are underrepresented at the highest levels of orthopedic sports medicine leadership including department chair (female: 0% [n = 0]), division chief (female: 4% [n = 4]; URM: 3% [n = 3]), and fellowship director (female: 3.3% [n = 3]; URM: 4.4% [n = 4]). Studies from prominent orthopedic sports medicine journals (American Journal of Sports Medicine, Arthroscopy, Journal of Shoulder and Elbow Surgery, and Sports Health) show a 12.1% increase in female involvement in orthopedic sports medicine research from 1972 to 2018; however, this increase captures 59.3% (n = 2,953) females with degrees other than an MD. CONCLUSIONS: Although increasingly more females and underrepresented minorities are joining orthopedic sports medicine, the rate of diversification remains slow and current involvement in leadership and research is minimal. Targeted efforts aimed at increasing research opportunities and inspiring interest through mentorship for URMs and females in orthopedics is essential to drive change toward parity. LEVEL OF EVIDENCE: Level IV. Systematic Review. See Instructions for Authors for a complete description of levels of evidence.

Staged Repair of Simultaneous Bilateral Proximal Hamstring Rupture and 2 Year Outcome: A Case Report.

CASE: A 53-year-old man presented with simultaneous, bilateral proximal hamstring ruptures. He underwent open, staged surgical repair of the proximal hamstrings, followed by a modified course of rehabilitation. At 2-year follow-up, the patient reports excellent outcomes. CONCLUSION: Simultaneous, bilateral, 3-tendon rupture of the proximal hamstrings is a rare lower extremity injury. Surgical treatment of such injuries presents several unique challenges. Staged surgical repair is an effective treatment option.

Scalable Nanopore sequencing of human genomes provides a comprehensive view of haplotype-resolved variation and methylation.

Long-read sequencing technologies substantially overcome the limitations of short-reads but have not been considered as a feasible replacement for population-scale projects, being a combination of too expensive, not scalable enough or too error-prone. Here we develop an efficient and scalable wet lab and computational protocol, Napu, for Oxford Nanopore Technologies long-read sequencing that seeks to address those limitations. We applied our protocol to cell lines and brain tissue samples as part of a pilot project for the National Institutes of Health Center for Alzheimer's and Related Dementias. Using a single PromethION flow cell, we can detect single nucleotide polymorphisms with F1-score comparable to Illumina short-read sequencing. Small indel calling remains difficult within homopolymers and tandem repeats, but achieves good concordance to Illumina indel calls elsewhere. Further, we can discover structural variants with F1-score on par with state-of-the-art de novo assembly methods. Our protocol phases small and structural variants at megabase scales and produces highly accurate, haplotype-specific methylation calls.

Outcomes of Biceps Tenodesis Variations With Concomitant Rotator Cuff Repair: A Multicenter Database Analysis.

Background: Studies to date comparing biceps tenodesis methods in the setting of concomitant rotator cuff repair (RCR) have demonstrated relatively equivalent pain and functional outcomes. Purpose: To compare biceps tenodesis constructs, locations, and techniques in patients who underwent RCR using a large multicenter database. Study Design: Cohort study; Level of evidence, 3. Methods: A global outcome database was queried for patients with medium- and large-sized tears who underwent biceps tenodesis with RCR between 2015 and 2021. Patients ≥18 years of age with a minimum follow-up of 1 year were included. The American Shoulder and Elbow Surgeons, Single Assessment Numeric Evaluation, visual analog scale for pain, and Veterans RAND 12-Item Health Survey (VR-12) scores were compared at 1 and 2 years of follow-up based on construct (anchor, screw, or suture), location (subpectoral, suprapectoral, or top of groove), and technique (inlay or onlay). Nonparametric hypothesis testing was used to compare continuous outcomes at each time point. The proportion of patients achieving the minimal clinically important difference (MCID) at the 1- and 2-year follow-ups were compared between groups using chi-square tests. Results: A total of 1903 unique shoulder entries were analyzed. Improvement in VR-12 Mental score favored anchor and suture fixations at 1 year of follow-up (P = .042) and the onlay tenodesis technique at 2 years of follow-up (P = .029). No additional tenodesis comparisons demonstrated statistical significance. The proportion of patients with improvement exceeding the MCID did not differ based on tenodesis methods for any outcome score assessed at the 1- or 2-year follow-up. Conclusion: Biceps tenodesis with concomitant RCR led to improved outcomes regardless of tenodesis fixation construct, location, or technique. A clear optimal tenodesis method with RCR remains to be determined. Surgeon preference and experience with various tenodesis methods as well as patient clinical presentation should continue to guide surgical decision-making.

Phased nanopore assembly with Shasta and modular graph phasing with GFAse.

As a step towards simplifying and reducing the cost of haplotype resolved de novo assembly, we describe new methods for accurately phasing nanopore data with the Shasta genome assembler and a modular tool for extending phasing to the chromosome scale called GFAse. We test using new variants of Oxford Nanopore Technologies' (ONT) PromethION sequencing, including those using proximity ligation and show that newer, higher accuracy ONT reads substantially improve assembly quality.

Outcomes of young active patients with displaced clavicle fractures treated with Rockwood pin.

PURPOSE: Various fixation techniques have been described for midshaft clavicle fractures in the literature. We hypothesized that use of the Rockwood pin for fixation of displaced midshaft clavicle fractures would result in favorable outcomes in a young active cohort. METHODS: Patients aged 10-35 years who underwent Rockwood clavicle pin fixation at a single institution were identified. Preoperative and postoperative radiographs were reviewed and assessed for fracture characteristics, postoperative alignment, and radiographic union. Postoperative outcome scores were obtained. RESULTS: A total of 39 patients (age 17.3 ± 3.9 years) with clavicle fracture treated with Rockwood pin were identified. Radiographic review demonstrated that 88% of fractures were 100%, or more, displaced, and surgery achieved near-anatomic reduction in 92% of cases. Average time to radiographic union was 2.3 ± 0.8 months, and average time to clinical union was 2.5 ± 0.3 months. One patient required revision for nonunion (3%). Complete outcome responses were obtained for 24 patients, with an average 40 ± 27.7 months of follow-up. Mean Total Clavicle Functional score was 2.75 ± 3.6 for minor patients. For adult patients, Nottingham Clavicle score was 90.7 ± 10.7, mean American Shoulder and Elbow Society score was 92.4 ± 11.2, and mean Single Assessment Numerical Evaluation score was 88.8 ± 21.5. 77% of adults reported no long-term functional limitation; 54% reported a bump at the prior fracture site, but 100% reported satisfaction with shoulder appearance. CONCLUSIONS: In our cohort of young active patients, treatment with Rockwood pin allowed for anatomic reduction, healing with a low nonunion rate, and favorable patient reported outcomes.

Scalable Nanopore sequencing of human genomes provides a comprehensive view of haplotype-resolved variation and methylation.

Long-read sequencing technologies substantially overcome the limitations of short-reads but to date have not been considered as feasible replacement at scale due to a combination of being too expensive, not scalable enough, or too error-prone. Here, we develop an efficient and scalable wet lab and computational protocol for Oxford Nanopore Technologies (ONT) long-read sequencing that seeks to provide a genuine alternative to short-reads for large-scale genomics projects. We applied our protocol to cell lines and brain tissue samples as part of a pilot project for the NIH Center for Alzheimer's and Related Dementias (CARD). Using a single PromethION flow cell, we can detect SNPs with F1-score better than Illumina short-read sequencing. Small indel calling remains to be difficult inside homopolymers and tandem repeats, but is comparable to Illumina calls elsewhere. Further, we can discover structural variants with F1-score comparable to state-of the-art methods involving Pacific Biosciences HiFi sequencing and trio information (but at a lower cost and greater throughput). Using ONT based phasing, we can then combine and phase small and structural variants at megabase scales. Our protocol also produces highly accurate, haplotype-specific methylation calls. Overall, this makes large-scale long-read sequencing projects feasible; the protocol is currently being used to sequence thousands of brain-based genomes as a part of the NIH CARD initiative. We provide the protocol and software as open-source integrated pipelines for generating phased variant calls and assemblies.

Arthroscopic treatment for intra-articular fibroma of the tendon sheath in a teenager.

An adolescent female patient presented with atraumatic left knee pain and limited flexion. MRI demonstrated evidence of a soft tissue lesion abutting the posterior cruciate ligament. Differential diagnosis included pigmented villonodular synovitis (PVNS) and fibroma of the tendon sheath (FTS). Following arthroscopic biopsy, histopathological evaluation confirmed FTS. The tumour was then excised via an arthroscopic approach. This case report provides a unique example of FTS abutting the cruciate ligaments in an uncommonly young female patient. It highlights the importance of including benign processes, such as FTS, in the differential with more aggressive-type diagnoses like PVNS. Furthermore, this case exemplifies an appropriate surgical indication for FTS. Finally, it emphasises the importance of communication and collaboration among orthopaedic subspecialists in providing safe and effective arthroscopic treatment of this unique tumour presentation.

Outcomes of Biceps Tenotomy Versus Tenodesis During Arthroscopic Rotator Cuff Repair: An Analysis of Patients From a Large Multicenter Database.

Background: Studies to date evaluating biceps tenotomy versus tenodesis in the setting of concomitant rotator cuff repair (RCR) have demonstrated relatively equivalent pain and functional outcomes. Hypothesis: It was hypothesized that a significant difference could be demonstrated for pain and functional outcome scores comparing biceps tenotomy versus tenodesis in the setting of RCR if the study was adequately powered. Study Design: Cohort study; Level of evidence, 3. Methods: The Arthrex Surgical Outcomes System database was queried for patients who underwent arthroscopic biceps tenotomy or tenodesis and concomitant RCR between 2013 and 2021; included patients had a minimum of 2 years of follow-up. Outcomes between treatment types were assessed using the American Shoulder and Elbow Surgeons Shoulder (ASES), Single Assessment Numeric Evaluation (SANE), visual analog scale (VAS) for pain, and Veterans RAND 12-Item Health Survey (VR-12) scores preoperatively and at 3 months, 6 months, 1 year, and 2 years postoperatively. Results were stratified by age at surgery (3 groups: <55, 55-65, >65 years) and sex. Results: Overall, 1936 primary RCRs were included for analysis (1537 biceps tenodesis and 399 biceps tenotomy patients). Patients who underwent tenotomy were older and more likely to be female. A greater proportion of female patients aged <55 years and 55 to 65 years received a biceps tenotomy compared with tenodesis (P = .012 and .026, respectively). All scores were comparable between the treatment types preoperatively and at 3 months, 6 months, and 1 year postoperatively. At 2-year follow-up, patients who received a biceps tenodesis had statistically more favorable ASES, SANE, VAS pain, and VR-12 scores (P ≤ .031); however, the differences did not exceed the minimal clinically important difference (MCID) for these measures. Conclusion: Our findings indicate that surgeons are more likely to perform a biceps tenotomy in female and older patients. Biceps tenodesis provided improved pain and functional scores compared with tenotomy at 2-year follow-up; however, the benefit did not exceed previously reported MCID for the outcome scores. Both procedures provided improvement in outcomes; thus, the choice of procedure should be a shared decision between the surgeon and patient.

Complete genomic and epigenetic maps of human centromeres.

Existing human genome assemblies have almost entirely excluded repetitive sequences within and near centromeres, limiting our understanding of their organization, evolution, and functions, which include facilitating proper chromosome segregation. Now, a complete, telomere-to-telomere human genome assembly (T2T-CHM13) has enabled us to comprehensively characterize pericentromeric and centromeric repeats, which constitute 6.2% of the genome (189.9 megabases). Detailed maps of these regions revealed multimegabase structural rearrangements, including in active centromeric repeat arrays. Analysis of centromere-associated sequences uncovered a strong relationship between the position of the centromere and the evolution of the surrounding DNA through layered repeat expansions. Furthermore, comparisons of chromosome X centromeres across a diverse panel of individuals illuminated high degrees of structural, epigenetic, and sequence variation in these complex and rapidly evolving regions.

Management of bipolar shoulder injuries with humeral head allograft in patients with active, uncontrolled seizure disorder: case series and review of literature.

BACKGROUND: The purpose of this study is to present surgical outcomes after humeral head allograft augmentation and glenoid-based procedures in patients with active, uncontrolled seizure activity and anterior shoulder instability. METHODS: A retrospective review of a surgical database for patients with active seizure disorder and with recurrent shoulder instability managed with humeral head augmentation was performed. All patients underwent surgical intervention. Postoperative outcomes including Shoulder Pain and Disability Index, Simple Shoulder Test, American Shoulder and Elbow Surgeons questionnaire, and the Short Form Health Survey (SF-12) were recorded at a minimum of 2 years. We hypothesized that appropriate management of the bony defects in these bipolar injuries would result in low recurrence and satisfactory outcomes. RESULTS: Ten patients including 8 males and 2 females (15 shoulders) with active seizure-related shoulder instability underwent surgical intervention including allograft bone grafting of the Hill-Sachs lesion for anterior shoulder instability. The average age was 27 years. All patients reported recurrent seizures postoperatively, but only one sustained a shoulder dislocation after surgery that was unrelated to seizure activity.Self-reported satisfaction was "much better" or "better" in 92% of shoulders. Average outcome scores were as follows: American Shoulder and Elbow Surgeons score = 67 (33-100), Shoulder Pain and Disability Index = 32.5 (0-83), Simple Shoulder Test = 9.4 (5-12), SF-12 PCS = 44.1 (21-65), and SF-12 MCS = 50.6 (21-61). The average follow-up was 4.8 years. CONCLUSION: Management of bipolar shoulder injuries with humeral head allograft augmentation and glenoid based surgery leads to low recurrence rates and good clinical outcomes in patients with uncontrolled, seizure-related shoulder instability.

Biomechanical Evaluation of Anterolateral Ligament Repair Augmented with Internal Brace.

Injuries to the anterolateral ligament (ALL) of the knee are commonly associated with anterior cruciate ligament (ACL) ruptures. Biomechanical studies have demonstrated conflicting results with regard to the role of the ALL in limiting tibial internal rotation. Clinically, residual pivot shift following ACL reconstruction has been reported to occur up to 25% and has been correlated with poor outcomes. As such, surgical techniques have been developed to enhance rotational stability. Recent biomechanical studies have demonstrated restoration of internal rotational control following ALL reconstruction. The purpose of our study was to understand the biomechanical effects of ACL reconstruction with an ALL internal brace augmentation. We hypothesized that (1) sectioning of the ALL while preserving other lateral extra-articular structures would lead to significant internal rotation laxity and gap formation and (2) ALL repair with internal brace augmentation would lead to reduction in internal rotation instability and gap formation. In total, 10 fresh-frozen cadaveric knees were thawed and biomechanically tested in internal rotation for 10 cycles of normal physiologic torque in the intact, ACL-deficient, ACL/ALL-deficient, ACL-reconstructed, and ALL-repaired conditions. Each condition was tested at 30, 60, and 90 degrees of flexion. Following the final ALL-repaired condition, specimens were additionally subjected to a final internal rotation to failure at 1 degree at the last-tested degree of flexion. Kinematic measurements of angle and linear gap between the femur and tibia were calculated in addition to torsional stiffness and failure torque. As hypothesized, ALL repair with internal brace augmentation significantly reduced internal rotation angular motion and gap formation at flexion angles greater than 30 degrees. Additionally, ALL sectioning produced nonsignificant increases in internal rotation laxity and gap formation compared with ACL-deficient and ACL-reconstructed states, which did not support our other hypothesis.

In-line Pullout Strength of 2 Acetabular Fixation Methods for Ligamentum Teres Reconstruction of the Hip: A Cadaveric Study.

BACKGROUND: Ligamentum teres (LT) reconstruction is an appropriate alternative in select cases of LT full-thickness tears, resulting in hip micro- or macroinstability. Graft fixation at the acetabular fossa is critical to achieving the best functional results. PURPOSE: The purpose of this study is to compare the pullout strength of 2 graft fixation methods used for LT reconstruction of the hip. STUDY DESIGN: Controlled laboratory study. METHODS: In 7 cadaveric specimens, the acetabular socket was prepared after the native LT was transected and the femoral head was removed. Seven separate tibialis anterior grafts were then prepared by suturing a running-locking No. 2 suture on each tail of the graft. Three specimens had fixation of the graft to the acetabulum using an adjustable cortical suspension suture button; the remaining 4 were fixed to the acetabulum using a knotless suture anchor. Specimens were then mounted onto a custom jig within a mechanical test frame to allow for the in-line pull of the graft fixation construct. After a preload of 5 N, each specimen was loaded to failure at 0.5 mm/s. Stiffness and load to failure were measured for each specimen construct. RESULTS: Suture button fixation had a higher mean load to failure when compared with the knotless anchor fixation method (mean ± SD, 438.1 ± 114.3 vs 195.9 ± 50.0 N; P = .01). There was no significant difference in mean stiffness between the methods of fixation (24.5 ± 1.4 vs 26.5 ± 5.8 N/mm; P = .6). CONCLUSION: In this cadaveric study, the suture button fixation demonstrated greater load to failure than the knotless anchor fixation. CLINICAL RELEVANCE: Results of this study can guide surgical decision making when selecting an acetabular fixation method for LT reconstruction.