Machine learning, a subset of artificial intelligence, has become increasingly common in the analysis of orthopaedic data. The resources needed to utilize machine-learning approaches for data ...analysis have become increasingly accessible to researchers, contributing to a recent influx of research using these techniques. As machine learning becomes increasingly available, misapplication owing to a lack of competence becomes more common. Sensationalized titles, misused vernacular, and a failure to fully vet machine learning–derived algorithms are just a few issues that warrant attention. As the orthopaedic community’s knowledge on this topic grows, the flaws in our understanding of this field will likely become apparent, allowing for rectification and ultimately improvement of how machine learning is utilized in research.
Background:
Loss of initial reduction of the acromioclavicular joint after coracoclavicular (CC) ligament reconstruction remains a challenge for various repair techniques. Previous studies using ...polydioxanone suture cerclage augments for CC ligament reconstruction demonstrated poor clinical and biomechanical outcomes. Tape-style sutures have recently gained popularity because of their added stiffness and strength relative to traditional sutures. These tape cerclage systems have yet to be biomechanically studied in CC ligament reconstruction.
Purpose:
To determine the efficacy of a tape cerclage system as an augment to CC ligament reconstruction.
Study Design:
Controlled laboratory study.
Methods:
A total of 24 human cadaveric shoulders were utilized. These were divided into 4 repair groups: anatomic CC ligament reconstruction (ACCR), ACCR with a tape cerclage augment (ACCR + C), tendon graft sling with a cerclage augment (TGS + C), or tape cerclage sling alone (CS). The repairs underwent superior/inferior cyclic loading to evaluate for displacement. Specimens were visually inspected for cortical erosion by the tape cerclage after cyclic loading. Finally, the constructs underwent superior plane load-to-failure testing.
Results:
Less displacement after cyclic loading was observed in the ACCR + C (mean ± SD, 0.42 ± 0.32 mm), TGS + C (0.92 ± 0.42 mm), and CS (0.93 ± 0.39 mm) groups as compared with the ACCR group (4.42 ± 3.40 mm; P = .002). ACCR + C (813.3 ± 257.5 N), TGS + C (558.0 ± 120.7 N), and CS (759.5 ± 173.7 N) demonstrated significantly greater load at failure relative to ACCR (329.2 ± 118.2 N) (P < .001). ACCR + C (60.88 ± 17.3 N/mm), TGS + C (44.97 ± 9.15 N/mm), and CS (54.52 ± 14.24 N/mm) conferred greater stiffness than ACCR (27.43 ± 6.94 N/mm) (P = .001). No cortical erosion was demonstrated in any specimen after cyclic loading.
Conclusion:
In a cadaveric model at time zero, repairs utilizing a tape cerclage system confer significantly greater load to failure and stiffness, as well as decreased displacement with cyclic loading, when compared with traditional ACCR repair.
Clinical Relevance:
Tape cerclage augmentation may provide a useful augment for CC ligament reconstruction.
Periprosthetic osteolysis remains a leading complication of total hip and knee arthroplasty, often resulting in aseptic loosening of the implant and necessitating revision surgery. Wear-induced ...particulate debris is the main cause initiating this destructive process. The purpose of this article is to review recent advances in understanding of how wear debris causes osteolysis, and emergent strategies for the avoidance and treatment of this disease. A strong activator of the peri-implant innate immune this debris-induced inflammatory cascade is dictated by macrophage secretion of TNF-α, IL-1, IL-6, and IL-8, and PGE2, leading to peri-implant bone resorption through activation of osteoclasts and inhibition of osteoblasts through several mechanisms, including the RANK/RANKL/OPG pathway. Therapeutic agents against proinflammatory mediators, such as those targeting tumor necrosis factor (TNF), osteoclasts, and sclerostin, have shown promise in reducing peri-implant osteolysis in vitro and in vivo; however, radiographic changes and clinical diagnosis often lag considerably behind the initiation of osteolysis, making timely treatment difficult. Considerable efforts are underway to develop such diagnostic tools, therapies, and identify novel targets for therapeutic intervention.
We aimed to biomechanically evaluate the distal pronator quadratus and compare two locations of distal transection on the strength of the subsequent repair.
Eighteen fresh-frozen cadaveric specimens ...were dissected to the pronator quadratus muscle. Specimens were randomly allocated for transection of the pronator quadratus at the myotendinous junction (red group) or parallel to the myotendinous junction at the midsection of the distal tendinous zone (white group). For both groups, repair of the muscle was performed using two figure-of-8 sutures. The radius and ulna were positioned in 90° of wrist extension. The proximal muscular pronator quadratus was fixed in a cryo-clamp. Load-to-failure testing of the repair was performed at 1 mm/s with maximum amount of force applied to the pronator quadratus recorded for each specimen.
The pronator quadratus had a mean width, height, and area of 31.41 ± 5.74 mm, 53.79 ± 7.46 mm, and 1604.27 ± 429.20 mm2 respectively. The pronator quadratus distal tendinous zone had a mean width, height, and area of 29.71 ± 5.83 mm, 12.22 ± 2.79 mm, 282.94 ± 148.30 mm2 respectively. There was no significant difference between the two groups for pronator quadratus height, width, total area, or tendinous zone height, width, or total area. The average load to failure for the white group was significantly higher than that of the red group (29.46 ± 4.24 N vs. 13.78 N ± 6.66 N).
Incision and repair of the pronator quadratus in the distal tendinous region is stronger than incision and repair at the red myotendinous junction of the distal PQ.
•A more detailed cadaveric analysis of the Pronator Quadratus muscle.•A novel biomechanical testing apparatus utilizing a cryo-clamp mechanism.•Insight into the location of incisions of the pronator quadratus muscle.
Lumbosacral fixation is commonly used for the management of lumbosacral instability. As the sacrum mainly consists of cancellous bone, bicortical fixation, in which the pedicle screw penetrates the ...anterior sacral cortex, can help increase the strength of fixation. However, this method carries a risk to the L5 nerves which lie anterior to the sacrum at this level.
The goal of this study is to determine a safe zone for the placement of S1 pedicle screws to decrease the likelihood of L5 nerve injury.
Retrospective imaging review.
This study evaluated imaging data of patients who underwent lumbar spine magnetic resonance imaging (MRI) at our institute between September 1, 2020 and September 1, 2021.
T1-weighted axial MRIs were measured at the level of S1 pedicle screw placement. The space medial and lateral to the L5 nerve root on the anterior sacrum were measured and defined as safe zones. Additionally, the nerve width and sacral lengths were measured at this level.
The distribution of the measurements were evaluated to determine a medial and lateral safe zone, as well as the average nerve width at the level of S1 pedicle screw placement. Correlation analysis was performed to determine a relationship between safe zone sizes and sacral size.
A total of 400 MRIs were analyzed. The average medial safe zone measured was 32.8 mm (95% CI: 32.2–33.4) with no nerves lying within 22.3 mm of the midline sacrum. The average lateral safe zone measured was 17.7 mm (95% CI: 17.1–18.2), with no nerves within 5.3 mm of the lateral border of the sacrum. The average nerve root width was 6.2 mm (95% CI: 6.13–6.34). An increased sacral length was associated with a larger medial (p<.001) and lateral (p<.001) safe zone.
Our study revealed lateral and medial safe zones for the placement of S1 pedicle screws to avoid iatrogenic nerve injury in a retrospective cohort of 400 patients. There were no L5 nerve roots found within 22.3 mm of the sacrum's mid-axis or within 5.3 mm of the sacrum's anterolateral border. These defined safe zones can be used during pedicle screw planning and placement to decrease the risk of injury to the L5 nerve root.
Despite their clinical importance in maintaining the stability of the pinch mechanism, injuries of the radial collateral ligament (RCL) of the index finger may be underrecognized and underreported. ...The purpose of this biomechanical study was to compare the repair of index finger RCL tears with either a standard suture anchor or suture tape augmentation.
The index fingers from 24 fresh-frozen human cadavers underwent repair of torn RCLs using either a standard suture anchor or suture tape augmentation. Following the repairs, the initial displacement of the repair with a 3-N ulnar deviating load was evaluated. Next, the change in displacement (cyclic deformation) of the repair after 1,000 cycles of 3 N of ulnar deviating force was calculated (displacement of the 1000th cycle - displacement of the first cycle). Finally, the amount of force required to cause clinical failure (30° ulnar deviation) of the repair was determined.
Suture tape augmentation repairs displayed significantly less cyclic deformation (0.8 ± 0.5 mm) after cyclic loading than suture anchor repairs (1.8 ± 0.7 mm). There was no significant difference in the force required to cause the clinical failure of the repairs between the suture tape (35.1 ± 18.1 N) and suture anchor (24.5 ± 9.2 N) repairs.
Index finger RCL repair with suture tape augmentation results in decreased deformation with repetitive motion compared with RCL repair alone.
Suture tape augmentation may allow for early mobilization following index finger RCL repair by acting as a brace that protects the repaired ligament from deforming forces.
There are a wide variety of interbody devices available for use in transforaminal lumbar interbody fusion (TLIF). While traditionally these interbodies are bullet-shaped, crescent-shaped cages have ...become increasingly common. There is a paucity of literature comparing the effect of cage geometry with substratification for surgical approach (minimally invasive (MIS) vs. open). The aim of this study was to determine the effect of implant geometry, positioning, and surgical approach on the correction of different spinal alignment parameters in patients undergoing TLIF. A retrospective chart and imaging review was performed on 103 patients with a total of 131 instrumented segments performed by a single surgeon. Preoperative, initial postoperative, and final postoperative standing lateral lumbar radiographs were evaluated for lumbar lordosis (LL), segmental lordosis (SL), anterior disc height (ADH), and posterior disc height (PDH). Anterior-posterior implant positioning was recorded for initial and final postoperative radiographs. These measurements were compared among four groups: open bullet (OB), MIS bullet (MB), open crescent (OC), and MIS crescent (MC). SL increased in all groups by a mean of 2.9° at initial imaging and 2.2° at final imaging. The OC group had greater initial improvement in SL compared to the MB group (p = 0.02), though this effect was lost at final follow-up (p = 0.11). The OB and OC groups conferred greater initial improvement in ADH (p = 0.02; p = 0.04), while the OC group had greater final improvement in ADH compared to the MB and MC groups (p = 0.01; p = 0.01). The OC group had less initial improvement in PDH compared with the other groups (p = 0.03, p = 0.02, p < 0.01). The MB group provided greater final improvement in PDH compared with the MC and OC groups (p = 0.04, p = 0.01). Cage geometry, surgical approach, and implant position all demonstrated a statistically significant but clinically minor impact on segmental alignment for TLIF procedures.
To quantify cellular senescence in supraspinatus tendon and subacromial bursa of humans with rotator cuff tears and to investigate the in vitro efficacy of the senolytic dasatinib + quercetin (D+Q) ...to eliminate senescent cells and alter tenogenic differentiation.
Tissue was harvested from 41 patients (mean age, 62 years) undergoing arthroscopic rotator cuff repairs. In part 1 (n = 35), senescence was quantified using immunohistochemistry and gene expression for senescent cell markers (p16 and p21) and the senescence-associated secretory phenotype (SASP) (interleukin IL 6, IL-8, matrix metalloproteinase MMP 3, monocyte chemoattractant protein MCP 1). Senescence was compared between patients <60 and ≥60 years old. In part 2 (n = 6) , an in vitro model of rotator cuff tears was treated with D+Q or control. D+Q, a chemotherapeutic and plant flavanol, respectively, kill senescent cells. Gene expression analysis assessed the ability of D+Q to kill senescent cells and alter markers of tenogenic differentiation.
Part 1 revealed an age-dependent significant increase in the relative expression of p21, IL-6, and IL-8 in tendon and p21, p16, IL-6, IL-8, and MMP-3 in bursa (P < .05). A significant increase was seen in immunohistochemical staining of bursa p21 (P = .028). In part 2, D+Q significantly decreased expression of p21, IL-6, and IL-8 in tendon and p21 and IL-8 in bursa (P < .05). Enzyme-linked immunosorbent assay analysis showed decreased release of the SASP (IL-6, MMP-3, MCP-1; P = .002, P = .024, P < .001, respectively). Tendon (P = .022) and bursa (P = .027) treated with D+Q increased the expression of COL1A1.
While there was an age-dependent increase in markers of cellular senescence, this relationship was not consistently seen across all markers and tissues. Dasatinib + quercetin had moderate efficacy in decreasing senescence in these tissues and increasing COL1A1 expression.
This study reveals that cellular senescence may be a therapeutic target to alter the biological aging of rotator cuffs and identifies D+Q as a potential therapy.
Subscapularis failure is a troublesome complication following anatomic total shoulder arthroplasty (aTSA). Commonly discarded during aTSA, the long head of the biceps tendon (LHBT) may offer an ...efficient and cheap autograft for the augmentation of the subscapularis repair during aTSA. The purpose of this study was to biomechanically compare a standard subscapularis peel repair to 2 methods of subscapularis peel repair augmented with LHBT.
18 human cadaveric shoulders (61 ± 9 years of age) were used in this study. Shoulders were randomly assigned to biomechanically compare subscapularis peel repair with (1) traditional single-row repair, (2) single row with horizontal LHBT augmentation, or (3) single row with V-shaped LHBT augmentation. Shoulders underwent biomechanical testing on a servohydraulic testing system to compare cyclic displacement, load to failure, and stiffness.
There were no significant differences in the cyclic displacement between the 3 techniques in the superior, middle, or inferior portion of the subscapularis repair (P > .05). The horizontal (436.7 ± 113.3 N; P = .011) and V-shape (563.3 ± 101.0 N; P < .001) repair demonstrated significantly greater load to failure compared with traditional repair (344.4 ± 82.4 N). The V-shape repair had significantly greater load to failure compared to the horizontal repair (P < .001). The horizontal (61.6 ± 8.4 N/mm; P < .001) and the V-shape (62.8 ± 6.1; P < .001) repairs demonstrated significantly greater stiffness compared to the traditional repair (47.6 ± 6.2 N). There was no significant difference in the stiffness of the horizontal and V-shape repairs (P = .770).
Subscapularis peel repair augmentation with LHBT autograft following aTSA confers greater time zero load to failure and stiffness when compared to a standard subscapularis peel repair.
STUDY DESIGN.This was an observational cohort study of patients receiving multilevel thoracic and lumbar spine surgery.
OBJECTIVE.The aim of this study was to identify which patients are at high risk ...for allogeneic transfusion which may allow for better preoperative planning and employment of specific blood management strategies.
SUMMARY OF BACKGROUND DATA.Multilevel posterior spine surgery is associated with a significant risk for major blood loss, and allogeneic blood transfusion is common in spine surgery.
METHODS.A univariate logistic regression model was used to identify variables that were significantly associated with intraoperative allogeneic transfusion. A multivariate forward stepwise logistic regression model was then used to measure the adjusted association of these variables with intraoperative transfusion.
RESULTS.Multilevel thoracic and lumbar spine surgery was performed in 921 patients. When stratifying patients by preoperative platelet count, patients with pre-operative thrombocytopenia and severe thrombocytopenia had a significantly higher rate of transfusion than those who were not thrombocytopenic. Furthermore, those with severe thrombocytopenia had a higher rate of red blood cells, fresh frozen plasma, and platelet transfusion than those with higher platelet counts. Multivariate logistic regression found that preoperative platelet count was the most significant contributor to transfusion, with a platelet count ≤100 having an adjusted odds ratio (OR) of transfusion of 4.88 (95% confidence interval CI 1.58–15.02, P = 0.006). Similarly, a platelet count between 101and 150 also doubled the risk of transfusion with an adjusted OR of 2.02 (95% CI 1.01–4.04, P = 0.047). The American Society of Anesthesiologists classification score increased the OR of transfusion by 2.5 times (OR = 2.52, 95% CI 1.54–4.13), whereas preoperative prothrombin time and age minimally increased the risk.
CONCLUSION.Preoperative thrombocytopenia significantly contributes to intraoperative transfusion in multilevel thoracic lumbar spine surgery. Identifying factors that may increase the risk for transfusion could be of great benefit in better preoperative counseling of patients and in reducing overall cost and postoperative complications by implementing strategies and techniques to reduce blood loss and blood transfusions.Level of Evidence2
