Intraobserver and Interobserver Reliability of the Snyder and Expanded SLAP Classification System: A Video Study.

Background: Superior labral anterior and posterior (SLAP) tears are a common finding in overhead athletes. The original classification system produced by Snyder in 1990 contained 4 types of SLAP tears and was later expanded to 10 types. The classification has been challenging because of inconsistencies between surgeons making diagnoses and treatments based on the diagnosis. Furthermore, patient factors-such as age and sports played-affect the treatment algorithms, even across similarly classified SLAP tears. Purpose: To (1) assess the interobserver and intraobserver reliability of the Snyder and expanded SLAP (ESLAP) classification systems and (2) determine the consistency of treatment for a given SLAP tear depending on different clinical scenarios. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: A total of 20 arthroscopic surgical videos and magnetic resonance imaging scans of patients with SLAP tears were sent to 20 orthopaedic sports medicine surgeons at various stages of training. Surgeons were asked to identify the type of SLAP tear using the Snyder and ESLAP classifications. Surgeons were then asked to determine the treatment for a SLAP tear using 4 clinical scenarios: (1) in the throwing arm of an 18-year-old pitcher; (2) in the dominant arm of an 18-year-old overhead athlete; (3) a 35-year-old overhead athlete; (4) or a 50-year-old overhead athlete. Responses were recorded, and the cases were shuffled and sent back 6 weeks after the initial responses. Results were then analyzed using the Fleiss kappa coefficient (κ) to determine interobserver and intraobserver degrees of agreement. Results: There was moderate intraobserver reliability in both the Snyder and ESLAP classifications (κ = 0.52) and fair interobserver reliability for both classification systems (Snyder, κ = 0.31; ESLAP, κ = 0.30; P < .0001) among all surgeons. Additionally, there was only fair agreement (κ = 0.30; P < .0001) for the treatment modalities chosen by the reviewers for each case. Conclusion: This study demonstrated that SLAP tears remain a challenging problem for orthopaedic surgeons in diagnostics and treatment plans. Therefore, care should be taken in the preoperative discussion with the patient to consider all the possible treatment options because this may affect the postoperative recovery period and patient expectations.

Shear wave elastography ultrasound does not quantify mechanical properties of the ulnar collateral ligament of the elbow.

OBJECTIVE: To validate shear wave elastography (SWE) stiffness measurements for the ulnar collateral ligament (UCL) of the elbow compared to mechanical measurements. MATERIALS AND METHODS: Eleven fresh frozen human cadaveric upper extremities were evaluated by a musculoskeletal-specialized radiologist to provide SWE measurements used to calculate stiffness at 4 points along the anterior band of the UCL at various load states and flexion angles. Specimens were then dissected and optical markers were placed on the UCL to track displacement during applied force by a load frame, thereby providing measurements to calculate the mechanical stiffness. These two stiffness values were compared by ANOVA for all load states and flexion angles. RESULTS: Measurements of stiffness by SWE for the UCL were three orders of magnitude smaller than the true mechanical testing stiffness and no correlations between SWE and mechanical measurements of stiffness were found at 30, 60 or 90 degrees of elbow flexion (R2 = 0.004, p = 0.85; R2 = 0.001, p = 0.92; R2 = 0.15, p = 0.24 respectively). SWE stiffness was greatest near the insertion of the ligament and lowest in the mid-substance of the ligament (p = 0.0002). CONCLUSIONS: SWE stiffness did not correlate with mechanical measurements. Clinical utility of musculoskeletal SWE may be better defined when biomechanical properties or clinical outcomes can be correlated with SWE measurements. The ultimate clinical utility of SWE in musculoskeletal tissues may be qualitative, as demonstrated by differences throughout the length of the UCL in this study.

Biomechanical Analysis of Ideal Knee Flexion Angle for ACL Graft Tensioning Utilizing Multiple Femoral and Tibial Tunnel Locations.

Anterior cruciate ligament (ACL) graft failure rate has been reported to be greater than 5% at 5 years. Our study evaluated ACL excursion with anatomic and nonanatomic femoral and tibial tunnels to determine optimal flexion angle to tension the ACL to minimize excursion. Ten cadaveric knee specimens were used. The ACL was sectioned and the femoral and tibial attachments were marked. A 1/16-inch drill created a tunnel in the center of the ACL footprint on the tibia and femur and additional tunnels were made 5 mm from this. A suture was passed through each tunnel combination and attached to a string potentiometer. The knee was ranged from full extension to 120 degrees of flexion for 10 cycles while mounted in a custom fixture. The change in length (excursion) of the suture during movement was recorded for each combination of femoral and tibial tunnels. Anatomic reconstruction of the ACL with tunnel placement in the center of the femoral and tibial footprint did not result in an isometric graft, with excursion of the ACL during knee motion of 7.46 mm (standard deviation [SD]: 2.7mm), greatest at 2.84 degrees of flexion (SD: 4.22). The tunnel combination that resulted in the least excursion was a femoral footprint 5 mm anterior to the femoral and 5 mm posterior to the tibial footprint (4. 2mm, SD: 1.37 mm). The tunnel combination that resulted in the most excursion utilized femoral footprint 5 mm proximal to the femoral and 5 mm posterior to the tibial footprint (9.81 mm, SD: 2.68 mm). Anatomic ACL reconstruction results in significant excursion of the ACL throughout motion. If not tensioned properly, the ACL can stretch during range of motion, potentially leading to rerupture. To prevent stretching of the graft, the current biomechanical study recommends tensioning an anatomic ACL reconstruction at its point of maximal excursion, or between 0 and 5 degrees of flexion. The level of evidence is IV.

Proximal Tibial Osteotomies: Indications, Techniques, and Outcomes.

High tibial osteotomy (HTO) is a surgical procedure that can be used as a primary or as an adjunctive treatment for a variety of knee pathologies, most commonly isolated medial compartment arthrosis in a knee with varus alignment. More recently, indications for HTO have been expanded to include its use in combination with cartilage preserving techniques, to offload the effected compartment, and in conjunction with ligamentous reconstruction. HTO also has utility in delaying total knee arthroplasty (TKA) in select patients with favorable literature on future TKA outcomes. Numerous techniques for HTO have been published, however, medial opening wedge and lateral closing wedge osteotomies remain the most common. The purpose of this article is to summarize HTO patient selection and indications, surgical techniques, common complications, and review outcomes from recent literature. (Journal of Surgical Orthopaedic Advances 32(3):148-155, 2023).

Valgus fatigue and nonlinear damage accretion of the anterior bundle of the elbow medial collateral ligament (AMCL).

Failure by fatigue is one mechanism by which ligaments can rupture, with the accumulation of damage gradually degrading the ligament strength. Baseball pitchers who perform repeated high-level throwing continuously subject the medial ligament complex of the elbow to extreme levels of loading, which can lead to fatigue and eventual rupture. This study sought to investigate this behavior and quantify the fatigue properties of the anterior bundle of the medial collateral ligament (AMCL) with respect to valgus elbow torque. Eleven pairs of cadaveric elbow specimens were used for this study. One side of each pair was tested in vertical elongation at four flexion angles and then tested to failure at 90° of flexion. The contralateral specimens were tested in valgus fatigue at 90° of flexion using a specialized apparatus with application of known moments based on the elongation failure load. The average tensile failure load for the AMCL was 595.3 ± 201.9 N. During cycling, the average increase in the maximum valgus rotation angle was 4.77° ± 2.82°. The average maximum stretch of the AMCL middle band increased from 1.066 ± 0.017 to 1.076 ± 0.018 near the time of fatigue failure. The average cycles to failure for specimens tested at 90% and 80% of the estimated failure torque were 3211 ± 4721.33 and 25063 ± 30487.58, respectively. The nonlinear non-dimensional fatigue life and damage accretion results work in conjunction to predict the fatigue properties for a valgus elbow motion of arbitrary torque magnitude at 90° of elbow flexion.

Bone Marrow Edema, Clinical Significance, and Treatment Options: A Review.

Bone marrow edema (BME) is a descriptive term used to describe high-signal intensity changes detected on magnetic resonance fluid-sensitive sequences that could be attributed to a number of underlying pathologies. Regardless of the cause, physiologic remodeling of the subchondral bone can be limited because of ongoing joint forces, increased focalization of stress, and reduced healing capacity of the subchondral bone. BME is a known prognostic factor associated with pain, dysfunction, and progressive cartilage damage. This review summarizes the current known causes of BMEs, theories related to histopathological changes, and current treatment options including novel biologic surgical options.

The moving valgus stress test produces more ulnar collateral ligament change in length during extension than during flexion: a biomechanical study.

HYPOTHESIS AND BACKGROUND: Injuries to the elbow medial ulnar collateral ligament (mUCL) pose a diagnostic challenge, with the moving valgus stress test (MVST) currently accepted as the gold-standard clinical test. This study sought to biomechanically evaluate the change in length of the ulnar collateral ligament (UCL) during flexion-extension using a null hypothesis that the mUCL will not experience a greater change in length with movement than with static loading. METHODS: Seven fresh-frozen human cadaveric elbows were tested with static and dynamic valgus stress. We measured (1) ligament length with a multi-camera optical system, (2) elbow flexion with an incremental encoder, and (3) valgus deviation with an electronic inclinometer. With a force applied to the wrist to simulate a clinical stress examination, the elbow was flexed and extended in a physiological elbow simulator to mimic the flexion and extension of the MVST. RESULTS: The simulated MVST produced more elongation of the UCL compared with static stress testing (P < .001). Ninety degrees of flexion produced the highest mean change, and the anterior and posterior bands demonstrated different length change characteristics. Comparison of dynamic flexion and extension showed a statistically significant difference in change in length: The mUCL reached the greatest change during extension, with the greatest changes during extension near 90° of flexion. DISCUSSION AND CONCLUSION: The MVST produces significantly more elongation of the mUCL than either a static test or a moving test in flexion. This study provides biomechanical evidence of the validity of the MVST as a superior examination technique for injuries to the UCL.

Correlation of Force to Deformation of the Anterior Bundle of the Medial Collateral Ligament Through Consideration of Band Laxity.

The anterior bundle of the medial collateral ligament (AMCL) resists the loads that arise at the elbow during overhand throwing and has commonly been divided into posterior and anterior bands. While these anterior and posterior bands have been thought to bear the load at different flexion angles, any transition of the load distribution between the two bands is poorly understood and has not considered laxity (slack). This study considers the AMCL as three bands and quantifies the mechanical response to vertical distraction, simulating valgus-load joint opening, through the sequential superposition of the band responses after the elimination of inherent laxity. Eight cadaveric elbow specimens were used for the study. The intact AMCL of each specimen was tested under vertical distraction in a specialized load frame at four elbow flexion angles and then subsequently retested after two longitudinal transections. The greatest laxity at full extension and full flexion belonged to the posterior (1.9 mm) and anterior (2.4 mm) band, respectively. At the lesser and higher flexion angles, the greatest structural stiffness belonged to the anterior and middle band. The overall AMCL was the most structurally stiff at 60°, with approximately 150 N of force required for 2% elongation. This study shows that the different bands of the AMCL may have different load bearing properties at different flexion angles, causing each band to support different proportions of an imposed load. The presence of the laxity may impose a load-bearing delay, causing load-bearing in each band to begin asynchronously. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2027-2034, 2019.

An Algorithm for Diagnosing and Treating Primary and Recurrent Patellar Instability.

Major anatomic risk factors for recurrent patellar instability include trochlear dysplasia, patella alta, a lateralized tibial tuberosity, and medial patellofemoral ligament insufficiency. Acute first-time patellar dislocation may be treated nonoperatively in the absence of osteochondral injury. Recurrent patellar instability often requires medial patellofemoral ligament reconstruction, with osseous procedures reserved for patients with substantial underlying anatomic abnormalities. Surgical treatment of patellar instability is complex and should be individualized to address the needs of each patient.

Presence of bacteria in failed anterior cruciate ligament reconstructions.

BACKGROUND: Novel microbial detection technologies have revealed that chronic bacterial biofilms, which are recalcitrant to antibiotic treatment, are common in failed orthopedic procedures. QUESTIONS: Are bacteria present on failed anterior cruciate ligament (ACL) reconstructions? Is there a difference in the presence or nature of bacteria in failed ACL reconstructions relative to a control set of healthy ACL's? METHODS: We used a case-control study design, where we analyzed the bacterial composition of 10 failed ACL reconstructions and compared it to 10 native ACL's harvested during total knee arthroplasty. The IBIS Universal Biosensor was used to determine the nature of bacteria on ACL specimens, and fluorescent in situ hybridization (FISH) was used to visualize bacteria in a subset of cases. RESULTS: Bacteria are present in failed ACL reconstructions. Bacteria are present in ACL's harvested during total knee arthroplasty, but the nature of the species differs significantly between experimental and control sets. Twelve genera were detected in the experimental set (in both allografts and autografts), and in four samples multiple species were detected. In contrast, the control group was characterized by presence of Propionibacterium acnes. CONCLUSIONS: We demonstrate the presence of bacteria on failed ACLs surgeries, and open the door to investigate whether and how bacteria and the associated immune responses could possibly contribute to graft failure. CLINICAL RELEVANCE: If microbial pathogens can be linked to failed grafts, it could provide: (1) markers for early diagnosis of abnormal healing in ACL surgeries, and (2) targets for early treatment to prevent additional reconstruction surgeries.

Effectiveness of Platelet-rich Plasma Injection for Rotator Cuff Tendinopathy: A Prospective Open-label Study.

OBJECTIVE: Assess platelet rich plasma (PRP) injection for rotator cuff tendinopathy (RCT). DESIGN: Prospective open label study with 1-year follow-up. METHODS: Participants recruited from an outpatient sports medicine clinic had clinically and magnetic resonance image (MRI)-demonstrated RCT refractory to physical therapy and corticosteroid injection. They received one ultrasound-guided injection of 3.0 mL of 1% xylocaine followed by 3.5 mL of PRP at the lesion and surrounding tendon. PRIMARY OUTCOME: 0-10 visual analog scale (VAS; baseline, 8, 12, and 52 weeks). SECONDARY OUTCOMES: functional shoulder tests assessing rotator cuff strength and endurance (at baseline and 8 and 12 weeks), MRI severity (1-5 points [at baseline and 4 and 8 weeks]), and patient satisfaction (52 weeks). RESULTS: Eighteen participants with 19 assessed shoulders reported VAS pain score improvement from 7.5 ± 0.3 points to 0.5 ± 0.3 points by week 12 and 0.4 ± 0.2 (P = .0001) points at week 52. Functional outcomes significantly improved; the largest effect was seen in the external rotation test: 33.5 ± 5.7 seconds to 62.6 ± 7.2 seconds at week 12 (P = .0001). MRI appearance improved by 1 to 3 points in 16 of 18 assessed shoulders. Seventeen participants were "completely satisfied" (12) or "satisfied" (5). One participant was "unsatisfied." CONCLUSIONS: A single ultrasound-guided, intralesional injection of PRP resulted in safe, significant, sustained improvement of pain, function, and MRI outcomes in participants with refractory RCT. Randomized multidisciplinary effectiveness trials that add ultrasound and validated clinical outcome measures are needed to further assess PRP for RCT.

Characterization of a mixed MRSA/MRSE biofilm in an explanted total ankle arthroplasty.

Bacterial biofilms have been observed in many prosthesis-related infections, and this mode of growth renders the infection both difficult to treat and especially difficult to detect and diagnose using standard culture methods. We (1) tested a novel coupled PCR-mass spectrometric (PCR-MS) assay (the Ibis T5000) on an ankle arthroplasty that was culture negative on preoperative aspiration and then (2) confirmed that the Ibis assay had in fact detected a viable multispecies biofilm by further micrographic and molecular examinations, including confocal microscopy using Live/Dead stain, bacterial FISH, and reverse-transcriptase-PCR (RT-PCR) assay for bacterial mRNA. The Ibis technology detected Staphylococcus aureus, Staphylococcus epidermidis, and the methicillin resistance gene mecA in soft tissues associated with the explanted hardware. Viable S. aureus were confirmed using RT-PCR, and viable cocci in the biofilm configuration were detected microscopically on both tissue and hardware. Species-specific bacterial FISH confirmed a polymicrobial biofilm containing S. aureus. A novel culture method recovered S. aureus and S. epidermidis (both methicillin resistant) from the tibial metal component. These observations suggest that molecular methods, particularly the new Ibis methodology, may be a useful adjunct to routine cultures in the detection of biofilm bacteria in prosthetic joint infection.

New methods for the detection of orthopedic and other biofilm infections.

The detection and identification of bacteria present in natural and industrial ecosystems is now entirely based on molecular systems that detect microbial RNA or DNA. Culture methods were abandoned, in the 1980s, because direct observations showed that <1% of the bacteria in these systems grew on laboratory media. Culture methods comprise the backbone of the Food and Drug Administration-approved diagnostic systems used in hospital laboratories, with some molecular methods being approved for the detection of specific pathogens that are difficult to grow in vitro. In several medical specialties, the reaction to negative cultures in cases in which overt signs of infection clearly exist has produced a spreading skepticism concerning the sensitivity and accuracy of traditional culture methods. We summarize evidence from the field of orthopedic surgery, and from other medical specialties, that support the contention that culture techniques are especially insensitive and inaccurate in the detection of chronic biofilm infections. We examine the plethora of molecular techniques that could replace cultures in the diagnosis of bacterial diseases, and we identify the new Ibis technique that is based on base ratios (not base sequences), as the molecular system most likely to fulfill the requirements of routine diagnosis in orthopedic surgery.

Orthopaedic biofilm infections.

A recent paradigm shift in microbiology affects orthopaedic surgery and most other medical and dental disciplines because more than 65% of bacterial infections treated by clinicians in the developed world are now known to be caused by organisms growing in biofilms. These slime-enclosed communities of bacteria are inherently resistant to host defenses and to conventional antibacterial therapy, and these device-related and other chronic bacterial infections are unaffected by the vaccines and antibiotics that have virtually eliminated acute infections caused by planktonic (floating) bacteria. We examine the lessons that can be learned, within this biofilm paradigm, by the study of problems (e.g. non-culturability) shared by all biofilm infections and by the study of new therapeutic options aimed specifically at sessile bacteria in biofilms. Orthopaedic surgery has deduced some of the therapeutic strategies based on assiduous attention to patient outcomes, but much can still be learned by attention to modern research in related disciplines in medicine and dentistry. These perceptions will lead to practical improvements in the detection, management, and treatment of infections in orthopaedic surgery.

The effect of interference screw diameter on fixation of soft-tissue grafts in anterior cruciate ligament reconstruction.

PURPOSE: The purpose of this study was to evaluate the effect that interference screw diameter has on fixation strength of a soft-tissue anterior cruciate ligament (ACL) graft. METHODS: We prepared 32 fresh-frozen bovine tibiae with 9-mm ACL tibial tunnels. Accompanying 9-mm soft-tissue bovine Achilles grafts were also prepared. Bioabsorbable interference screws of increasing diameters were used for tibial fixation. There were 4 groups, consisting of 8-, 9-, 10-, and 11-mm screws for fixation of the 9-mm graft in the 9-mm tunnel. Tensile testing and cyclic loading from 50 to 250 N at 2 Hz for a total of 1,500 cycles were performed with a hydraulic biaxial materials testing machine. Graft slippage was measured with a video analysis technique with photo-reflective markers. At the end of cyclic testing, the grafts were loaded to failure, and the ultimate strength was recorded. RESULTS: All grafts failed at the tendon-bone-screw interface. The ultimate strength (+/- SD) was greatest for the 11-mm screw (624 +/- 133 N), with slightly decreased strength for the 10-mm (601 +/- 54 N), 9-mm (576 +/- 85 N), and 8-mm (532 +/- 185 N) screws. Graft slippage (+/- SD) was least for the 9-mm screw (2.65 +/- 2.38 mm). There were no statistically significant differences in ultimate strength and graft slippage between screws (P = .45 and P = .34, respectively). CONCLUSIONS: All interference screws tested provided adequate fixation strength. The results of this study show no statistical significance for ultimate strength or graft slippage with variable screw diameter. CLINICAL RELEVANCE: Aperture fixation with the interference screw technique provides adequate stability for soft-tissue grafts in ACL reconstruction. Although no statistical significance was found, there was a trend toward less graft-site motion when we used a screw diameter equal to tunnel size.

Midterm follow-up of opening-wedge high tibial osteotomy.

BACKGROUND: High tibial osteotomy is a valuable option for patients with varus gonarthrosis. To avoid difficulties with closing-wedge osteotomies, medial opening-wedge high tibial osteotomies have been advocated. HYPOTHESIS: Opening-wedge high tibial osteotomy is a good option in highly active patients with varus gonarthrosis who would like to delay or prevent progression to total knee arthroplasty without activity restrictions. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Twenty consecutive patients with varus gonarthrosis were treated with a medial opening-wedge high tibial osteotomy using the Puddu plate and allograft bone graft for a prospective study (14 men and 6 women; average age, 49.4 years [range, 36-67 years]). Gait analysis was performed preoperatively and at 6 months postoperatively. Preoperative radiographs, subjective ratings, and knee scores (Lysholm and Hospital for Special Surgery [HSS] scores) were obtained. At 2 years postoperatively and at the latest follow-up visit (average, 8.3 years), the subjective ratings and knee scores were repeated. RESULTS: Gait analysis revealed an abnormal weightbearing pattern preoperatively with the vertical ground-reaction force. The postoperative vertical ground-reaction force revealed a normal double peak pattern. The preoperative adduction moment was 29% greater than the 6-month postoperative adduction moment. The preoperative varus averaged 3.6° and was corrected to an average of 7.5° of valgus postoperatively. All patients subjectively rated their preoperative knee as poor. At 2 years postoperatively, most patients (14) rated their knee as good, with 5 excellent and only 1 fair rating. The average preoperative Lysholm and HSS knee scores were 54.2 and 75.9, respectively, compared with the 2-year postoperative averages of 89.1 and 92.7, respectively. At 8 years postoperatively, there was 70% survivorship with 42% of patients rating their knees as good or excellent. Five patients (25%) had undergone total knee arthroplasty. Lysholm and HSS knee scores were 83.0 and 86.8, respectively, for the surviving knees at 8 years postoperatively. CONCLUSION: Medial opening-wedge high tibial osteotomy produces good results in the midterm. After the osteotomy, a more normal appearing weightbearing pattern with double peaks was seen. The adduction moment significantly decreased, resulting in less contact pressure through the medial degenerative compartment of the knee. The authors recommend medial opening-wedge high tibial osteotomy for young patients with varus alignment and medial compartment arthritis to allow this patient population to remain highly active and delay progression to total knee arthroplasty without activity restrictions.

The distributed genome hypothesis as a rubric for understanding evolution in situ during chronic bacterial biofilm infectious processes.

Most chronic infectious disease processes associated with bacteria are characterized by the formation of a biofilm that provides for bacterial attachment to the host tissue or the implanted medical device. The biofilm protects the bacteria from the host's adaptive immune response as well as predation by phagocytic cells. However, the most insidious aspect of biofilm biology from the host's point of view is that the biofilm provides an ideal setting for bacterial horizontal gene transfer (HGT). HGT provides for large-scale genome content changes in situ during the chronic infectious process. Obviously, for HGT processes to result in the reassortment of alleles and genes among bacterial strains, the infection must be polyclonal (polymicrobial) in nature. In this review, we marshal the evidence that all of the factors are present in biofilm infections to support HGT that results in the ongoing production of novel strains with unique combinations of genic characteristics and that the continual production of large numbers of novel, but related bacterial strains leads to persistence. This concept of an infecting population of bacteria undergoing mutagenesis to produce a 'cloud' of similar strains to confuse and overwhelm the host's immune system parallels genetic diversity strategies used by viral and parasitic pathogens.

Autogenous osteochondral transfer in the femoral head after osteonecrosis.

Osteonecrosis of the femoral head is a major problem, especially in younger patients. Most of them need a total hip replacement. This article presents a case of a successful autologous osteochondral transfer.