Effect of Preoperative Lipidemic Control on Retear Rates After Rotator Cuff Repair in Patients With Hyperlipidemia.

BACKGROUND: In patients with hyperlipidemia, the risk of retear increases after rotator cuff repair (RCR). In particular, it has been reported that preoperative low-density lipoprotein cholesterol (LDL-C) level affects cuff integrity. However, there are no studies assessing whether lipidemic control affects cuff healing. PURPOSE: To evaluate the effect of preoperative lipidemic control on cuff integrity after arthroscopic RCR across cardiovascular disease risk groups in patients with hyperlipidemia. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: The authors retrospectively reviewed the charts of patients with hyperlipidemia who underwent arthroscopic double-row suture bridge RCR between 2014 and 2019. The included patients had LDL-C tested within 1 month before surgery. Magnetic resonance imaging was conducted 6 months after surgery to evaluate the integrity of the repaired cuff tendon. Patients were divided into groups of low, moderate, high, and very high risk according to the 4th Korean Dyslipidemia Guidelines. On the basis of the target LDL-C set in each risk group, patients were categorized into 2 groups: group C (controlled hyperlipidemia, less than target LDL-C) and group U (uncontrolled hyperlipidemia, target LDL-C or greater). The correlation between serum lipid profile, lipidemic control, and post-RCR integrity was evaluated. RESULTS: A total of 148 patients were analyzed, 51 in group U and 97 in group C. The retear rate was significantly higher in group U than in group C (23/51 [45.1%] vs 18/97 [18.6%], respectively; P = .001). The proportion of group U was significantly higher in the retear group than in the healing group (56.1% vs 26.2%; P = .001). In addition, the proportions of patients with uncontrolled diabetes mellitus (DM) (19.5% vs 3.7%; P = .002) and mediolateral (2.6 ± 1.2 cm vs 1.7 ± 1.1 cm; P < .001) and anteroposterior (2.2 ± 1.1 cm vs 1.6 ± 0.8 cm; P = .003) tear sizes were significantly different between the retear and healing groups, respectively. No significant difference in serum lipid profile, including LDL-C level (119.6 ± 31.3 vs 116.7 ± 37.2; P = .650), was observed between the retear and healing groups. Multivariate regression analysis identified uncontrolled hyperlipidemia (OR, 4.005; P = .001), uncontrolled DM (OR, 5.096; P = .022), and mediolateral tear size (OR, 1.764; P = .002) as independent risk factors for retear. The 2.0-cm mediolateral size cutoff and the 3 independent risk factors had significant associations with retear. CONCLUSION: Poor preoperative lipidemic control was significantly associated with poor healing after RCR. In addition to large mediolateral tear size, uncontrolled hyperlipidemia and DM were significant risk factors for retear. Moreover, poor lipidemic control compared with the recommended target level before surgery was more correlated with an increased retear rate than a preoperative LDL-C level.

RNA-Seq of an LPS-Induced Inflammation Model Reveals Transcriptional Profile Patterns of Inflammatory Processes.

The LPS-induced inflammation model is widely used for studying inflammatory processes due to its cost-effectiveness, reproducibility, and faithful representation of key hallmarks. While researchers often validate this model using clinical cytokine markers, a comprehensive understanding of gene regulatory mechanisms requires extending investigation beyond these hallmarks. Our study leveraged multiple whole-blood bulk RNA-seq datasets to rigorously compare the transcriptional profiles of the well-established LPS-induced inflammation model with those of several human diseases characterized by systemic inflammation. Beyond conventional inflammation-associated systems, we explored additional systems indirectly associated with inflammatory responses (i.e., ISR, RAAS, and UPR) using a customized core inflammatory gene list. Our cross-condition-validation approach spanned four distinct conditions: systemic lupus erythematosus (SLE) patients, dengue infection, candidemia infection, and staphylococcus aureus exposure. This analysis approach, utilizing the core gene list aimed to assess the model's suitability for understanding the gene regulatory mechanisms underlying inflammatory processes triggered by diverse factors. Our analysis resulted in elevated expressions of innate immune-associated genes, coinciding with suppressed expressions of adaptive immune-associated genes. Also, upregulation of genes associated with cellular stresses and mitochondrial innate immune responses underscored oxidative stress as a central driver of the corresponding inflammatory processes in both the LPS-induced and other inflammatory contexts.

Magnetic resonance imaging for relationship between the severity of perianchor fluid collection and rotator cuff integrity after arthroscopic double-row suture-bridge rotator cuff repair.

PURPOSE: The primary purpose of this study was to assess perianchor fluid collection (PFC) severity of medial anchor and rotator cuff integrity association after arthroscopic double-row suture-bridge rotator cuff repair (RCR) and the secondary purpose was to identify the demographic and radiologic risk factors for high-grade PFC. HYPOTHESIS: Re-tear rate would be significant higher in patients with high-grade PFC. METHODS: We retrospectively reviewed patients with arthroscopic double-row suture-bridge RCR for full-thickness rotator cuff tear (RCT) at our institution between February 2012 and May 2018. Based on the PFC severity, they were divided into the no-fluid (no fluid collection), low-grade (minimal or local fluid collection around the anchor), and high-grade (fluid collection beyond the entire length of the anchor) groups. Magnetic resonance imaging was performed 6 months postoperatively for assessing PFC severity and repaired rotator cuff integrity association, besides evaluating correlation between severity and various demographic and radiologic factors, including work level (low/medium/high) and RCT size. RESULTS: This study included 312 patients, 181 (58%) in the no fluid group, 82 (26.3%) in the low-grade PFC group, and 49 (15.7%) in the high-grade PFC group. Re-tear occurred in 73 (23.4%) patients and was more frequent in the high-grade group (26/49 [53.1%]) than in the no-fluid (27/181 [14.9%]; p<0.001) and low-grade (20/82 [24.4%]; p=0.001) groups, without statistically significant differences between the latter two (p=0.082). Among the demographic factors, work level (low/medium/high) differed significantly between the no-fluid (22.1%/58.0%/19.9%), low-grade (25.7%/46.3%/28.0%), and high-grade (26.5%/34.7%/38.8%) groups (p=0.026). Among the radiologic factors, the mediolateral tear size differed significantly between the three groups (no-fluid group: 1.7±0.8cm, low-grade group: 1.8±0.6cm, high-grade group: 2.2±1.0cm; p=0.003). Multivariate regression analysis showed that mediolateral tear size (odds ratio: 1.821; 95% confidence interval: 1.258-2.636; p=0.001) was an independent risk factor for high-grade PFC. CONCLUSIONS: After arthroscopic double-row suture-bridge RCR, the highest re-tear rate was observed in patients with high-grade PFC, while there was no significant difference in rates between no-fluid and low-grade PFC groups. As PFC severity increased, the risk of re-tear increased. In particular, larger mediolateral tear size was associated with high-grade PFC. LEVEL OF EVIDENCE: III; case-control study.

Risk factors for nonunion in patients with transcondylar fracture of the distal humerus after open reduction and internal fixation.

BACKGROUND: Transcondylar fractures have been reported to rarely occur in the distal humerus, and stable fixation is difficult because of the unique fracture pattern. However, few studies have reported the risk factors for nonunion after open reduction and internal fixation (ORIF). This study aimed to evaluate the demographic and surgical risk factors for nonunion in patients who had undergone ORIF for transcondylar fractures. METHODS: We retrospectively reviewed 68 patients who underwent ORIF for transcondylar fractures. Preoperative demographic factors, including diabetes mellitus (DM) and smoking, and operative factors, including fixation methods (eg, dual plate/single plate/tension band wiring [TBW]) were assessed as risk factors for nonunion. RESULTS: Nonunion occurred in 8 out of 68 patients (11.8%). Univariate analysis revealed that among the demographic factors, DM (4/8 [50%] vs. 8/60 [13.3%], P = .028) and smoking (3/8 [37.5%] vs. 4/60 [6.7%], P = .031) were significantly different between nonunion and union patients. Regarding operative factors, the fixation method (dual plate/single plate/TBW; 2 [25.0%]/2 [25.0%]/4 [50%] vs. 29 [48.3%]/25 [41.7%]/6 [10.0%], P = .033) showed significant differences between nonunion and union patients. Multivariate regression analysis showed that DM (odds ratio [OR], 10.560; 95% confidence interval [CI], 1.308-85.247; P = .027), smoking (OR 22.371; 95% CI, 2.111-237.081; P = .010), and TBW (OR 15.390; 95% CI, 1.348-175.666; P = .028) were independent risk factors for nonunion. CONCLUSIONS: Nonunion occurred in approximately 12% of the patients who underwent ORIF in the transcondylar region of the distal humerus. The risk of nonunion was higher in patients with DM than those who smoked. In addition, among the fixation methods, the TBW technique was a significant risk factor for nonunion.

No difference in biomechanical properties of simple, horizontal mattress, and double row repair in Bankart repair: a systematic review and meta-analysis of biomechanical studies.

BACKGROUND: Arthroscopic Bankart repair is the most common procedure in patients with anterior shoulder instability. Various repair techniques using suture anchors have been used to improve the strength of fixation and surgical outcomes in arthroscopic Bankart surgery. However, evidence regarding which method is superior is lacking. This systematic review and meta-analysis study was designed to compare the biomechanical results of simple versus horizontal mattress versus double-row mattress for Bankart repair. METHODS: A systematic search of the MEDLINE, Embase, and Cochrane Library databases was performed to identify comparative biomechanical studies comparing the simple, horizontal mattress, and double-row techniques commonly used in Bankart repair for anterior shoulder instability. Biomechanical results included the ultimate load to failure, stiffness, cyclic displacement, and mode of failure after the ultimate load. The methodological quality was assessed based on the Quality Appraisal for Cadaveric Studies (QUACS) scale for biomechanical studies. RESULTS: Six biomechanical studies comprising 125 human cadavers were included in this systematic review. In biomechanical studies comparing simple and horizontal mattress repair and biomechanical studies comparing simple and double-row repair, there were no significant differences in the ultimate load to failure, stiffness, or cyclic displacement between the repair methods. The median QUACS scale was 11.5 with a range from 10 to 12, indicating a low risk of bias. CONCLUSION: There was no biomechanically significant difference between the simple, horizontal mattress, and double-row methods in Bankart repair. Clinical evidence such as prospective randomized controlled trials should be conducted to evaluate clinical outcomes according to the various repair methods. LEVEL OF EVIDENCE: Systematic review, Therapeutic level IV.

Risk factors for residual popliteal cyst after arthroscopic decompression and cystectomy: Associated with degenerative cartilage lesions.

BACKGROUND: In previous studies, good results have been reported after arthroscopic treatment of popliteal cysts and concomitant intra-articular pathology. However, only a few studies have reported the associated factors with residual popliteal cysts. The aim of this study was to examine the clinical and radiographic outcomes and investigate the factors associated with the recurrence of popliteal cyst after arthroscopic cyst decompression and cyst wall resection. HYPOTHESIS: The authors hypothesized that residual popliteal cyst after arthroscopic decompression and cystectomy would be associated with degenerative cartilage lesions. PATIENTS AND METHODS: From December 2010 to December 2018, 54 patients with popliteal cysts were treated with arthroscopic decompression and cyst wall resection through an additional posteromedial cystic portal. Magnetic resonance imaging (MRI) or ultrasonography was used to observe whether the popliteal cyst had disappeared or decreased. The maximum diameter of the popliteal cyst was measured after surgery. The patients were classified into the disappeared and reduced groups according to the treatment outcome. Age, sex, symptom duration, preoperative degenerative changes based on the Kellgren-Lawrence (K-L) grade, cartilage lesions according to the International Cartilage Repair Society (ICRS) grades, synovitis, functional outcomes, and associated intra-articular lesions were compared between the two groups. The functional outcome was evaluated on the basis of the Rauschning and Lindgren knee score. The study included 22 men and 32 women, with mean age of 49.6 years (range, 5-82 years). According to the ICRS grade system, 28 (51.8%) patients had grade 0 to II, 26 (48.2%) patients had grade III to IV. RESULTS: Follow-up radiographic evaluation revealed that the cyst had completely disappeared in 20 patients (37%) and reduced in size in 34 (63%). The mean cyst size was decreased significantly from 5.7cm (range, 1.7-15cm) to 1.7cm (range, 0-6.4cm), and the Rauschning and Lindgren knee score showed improved clinical features in all the patients. Between the disappeared and reduced groups, the presence of degenerative cartilage lesions (p=0.022, odds ratio 8.702, 95% confidence interval: 1.368-55.362) showed statistically significant differences. DISCUSSION: Through the posteromedial cystic portal, cysts were completely removed in approximately 40% of patients, and the size was reduced in 60% of patients. Presence of degenerative cartilage lesion represents an associated risk factor for residual popliteal cyst. These findings could be helpful in ensuring explaining poor prognostic factors. LEVEL OF EVIDENCE: IIIb; retrospective cohort study.

Risk factors of tear progression in symptomatic small to medium-sized full-thickness rotator cuff tear: relationship between occupation ratio of supraspinatus and work level.

BACKGROUND: Previous studies reported that full-thickness rotator cuff tear (FTRCT) is a risk factor for tear progression. However, there is no clear consensus on the risk factors of tear progression in FTRCT. PURPOSE: To identify the demographic and radiologic risk factors of tear progression in small to medium FTRCTs. METHODS: We retrospectively reviewed 81 shoulders of patients diagnosed with small or medium FTRCTs using magnetic resonance imaging (MRI) who underwent conservative treatment from January 2017 to November 2021. Various demographic factors, including patient work level and radiological factors such as atrophy of rotator cuff muscles were analyzed to evaluate their association with tear progression. Work level was divided into high (heavy manual labor), medium (manual labor with less activity), and low (sedentary work activity). The atrophy of rotator cuff muscles was calculated by occupation ratio. RESULTS: Tear progression was observed in 48% (39/81) of patients (criterion for tear progression was medial-lateral or anterior-posterior tear length > 5 mm). In patients with tear progression, the lengths of medial-lateral and anterior-posterior tears progressed by 6 mm and 3 mm, respectively. Among the rotator cuff muscles, fatty degeneration and occupation ratio of the supraspinatus were only worsened (P = .014, P = 0.013, respectively). The mean MRI follow-up duration was 14.8 ± 9.0 months. The significant risk factors of tear progression were high work level (odds ratio [OR], 7.728; 95% CI, 1.204-49.610; P = .031), and occupation ratio of the supraspinatus muscle (OR, 0.308; 95% CI, 0.158-0.604; P = .001). The optimal cutoff value for the occupation ratio of the supraspinatus was 0.55 (sensitivity 74%, specificity 62%). CONCLUSIONS: Tear progression was observed in approximately 50% of patients with symptomatic small to medium FTRCTs. High physical work level and atrophy of the supraspinatus muscle were independent risk factors of tear progression. The risk of tear progression increases with occupation ratio of the supraspinatus muscle < 0.55 and heavy manual labor.

Intra-articular Injection of Autologous Adipose-Derived Stem Cells or Stromal Vascular Fractions: Are They Effective for Patients With Knee Osteoarthritis? A Systematic Review With Meta-analysis of Randomized Controlled Trials.

BACKGROUND: Intra-articular injection of adipose-derived stem cells, which are divided into adipose-derived mesenchymal stem cells (ASCs) and adipose-derived stromal vascular fractions (ADSVFs), has been reported to be a viable treatment modality for knee osteoarthritis (OA); however, its efficacy remains limited. PURPOSE: This study aimed to provide comprehensive information about the efficacy and safety of intra-articular injections of autologous ASCs and ADSVFs without adjuvant treatment in patients with knee OA. STUDY DESIGN: Meta-analysis; Level of evidence, 1. METHODS: A systematic search of the MEDLINE, Embase, Web of Science, and Cochrane Library databases was performed to identify randomized controlled trials (RCTs) that evaluated the efficacy and safety of intra-articular injections of autologous ASCs or ADSVFs without adjuvant treatments compared with placebo or hyaluronic acid in patients with knee OA. Clinically, the 100-mm visual analog scale for pain relief and the Western Ontario and McMaster Universities Osteoarthritis Index for functional improvement were implemented. Radiologically, cartilage status was assessed using magnetic resonance imaging (MRI). Procedure-related knee pain, swelling, and adverse events (AEs) were evaluated for safety. Additionally, we performed subgroup analyses comparing ASCs versus ADSVFs. Methodological quality was assessed using the modified Coleman Methodology Score (mCMS). RESULTS: A total of 5 RCTs were included in this study. Based on the meta-analysis, ASCs or ADSVFs showed significantly better pain relief at 6 months (Z = 7.62; P < .0001) and 12 months (Z = 7.21; P < .0001) and functional improvement at 6 months (Z = 4.13; P < .0001) and 12 months (Z = 3.79; P = .0002), without a difference in procedure-related knee pain or swelling compared with controls. Although a meta-analysis with regard to cartilage improvements was not performed owing to heterogeneous MRI assessment, 3 studies reported significantly improved cartilage status after the injection. No serious AEs associated with ASCs or ADSVFs were reported. Subgroup analyses showed similar efficacy between ASC and ADSVF treatments. The median mCMS was 70 (range, 55-75). CONCLUSION: For patients with knee OA, intra-articular injection of autologous ASCs or ADSVFs without adjuvant treatment showed remarkable clinical efficacy and safety at short-term follow-up. Some degree of efficacy has been shown for cartilage regeneration in knee OA, although the evidence remains limited. Further RCTs that directly compare ASCs and ADSVFs are needed.

Increased HbA1c Levels in Diabetics During the Postoperative 3-6 Months After Rotator Cuff Repair Correlated With Increased Retear Rates.

PURPOSE: To evaluate whether glycemic control affects the integrity of the repaired rotator cuff during the postoperative healing period after arthroscopic double-row suture bridge rotator cuff repair (RCR) METHODS: We retrospectively reviewed patients with diabetes mellitus (DM) who underwent arthroscopic double-row suture bridge RCR at our institution between March 2016 and November 2019. We included the patients who evaluated for serum glycosylated hemoglobin (HbA1c) levels within 1 month before and 3-6 months after surgery. Magnetic resonance imaging was conducted 6 months after surgery to evaluate the integrity of the repaired cuff tendon. Patients were categorized into two groups based on comparison between preoperative and postoperative HbA1c values: Group I (increased postoperative HbA1c) and Group D (same or decreased postoperative HbA1c). The correlation between preoperative/postoperative HbA1c, HbA1c increase/same or decrease (during the healing period), and post-RCR integrity was evaluated, including various demographic and radiologic factors. RESULTS: A total of 103 patients were analyzed, group I was 47, and group D was 56, respectively. The retear rate of 51.1% (24/47) in Group I was significantly higher than 14.3% (8/56) in Group D (P < .001). HbA1c levels measured 3-6 months after surgery (mean: 6.9; 95% CI: 6.6-7.3 vs mean: 6.5; 95% CI: 6.3-6.7, P = .034), and the proportion of group I and group D were significantly different (75%/25% vs 32.4%/67.6%, P < .001) between the retear and healing groups. Multivariable logistic regression analysis identified increased HbA1c as an independent risk factor for retear (odds ratio: 5.402; 95% CI: 2.072-14.086; P < .001). CONCLUSIONS: The glycemic control within 3-6 months after surgery when the healing process of the tendon was in progress had a significant effect on retear rate. In particular, the retear rate was higher when the HbA1c level increased at postoperative 3-6 months compared to before surgery. LEVEL OF EVIDENCE: Retrospective case-control comparative study, Level III.

Anteroposterior and Lateral Coverage of the Acromion: Prediction of the Rotator Cuff Tear and Tear Size.

Background: The aim of this study was to assess whether the anteroposterior coverage of the acromion reflecting acromial morphology affects the rotator cuff tear (RCT) and tear size, in addition to the lateral coverage. Methods: Medical records of 356 patients with RCTs, concentric osteoarthritis, and calcific tendinitis identified using three-dimensional computed tomography between January 2016 and December 2017 were retrospectively analyzed. The patients were divided into group A (those with RCTs) and group B (those with concentric osteoarthritis or calcific tendinitis). Subsequently, group A was subdivided into three categories according to the size of RCTs: small-to-medium, large, and massive. The lateral coverage was measured through the lateral acromial angle (LAA) and critical shoulder angle (CSA), whereas the anteroposterior coverage was measured via the acromial tilt (AT), acromiohumeral interval (AHI) in the sagittal view, and anteroposterior coverage index (APCI) as a new radiologic parameter. Results: Between groups A and B, CSA (34.5° ± 3.4° and 30.8° ± 3.4°, respectively), APCI (0.83 ± 0.10 and 0.75 ± 0.08, respectively), and AHI (6.3 ± 2.0 mm and 7.8 ± 1.8 mm, respectively) were significantly different (all p < 0.001), whereas LAA and AT did not show a significant difference between the groups (p = 0.089 and p = 0.665, respectively). The independent predictive radiologic parameters of the RCT were the CSA, APCI, and AHI (p < 0.001, p < 0.001, and p = 0.043, respectively); among these, the APCI showed the highest regression coefficient (odds ratio = 2.82). The parameters associated with the size of RCTs were CSA (p = 0.022) and AHI, of which AHI, in particular, had the most significant effect on both small-to-medium and large tears (all p < 0.001). Conclusions: Large CSA, high APCI, and low AHI were predictors of RCTs, with the APCI showing the strongest correlation. In addition to the large CSA, low AHI also correlated with the size of RCTs and affected the entire size groups. We suggest that both the lateral coverage and anteroposterior coverage of the acromion should be considered essential factors for predicting the presence of RCTs and tear size.

Patterns of labral tears and cartilage injury are different in femoroacetabular impingement and dysplasia.

The aim of this study was to assess injury patterns and risk factors of the acetabular labrum and associated cartilage in patients with femoroacetabular impingement (FAI) versus dysplasia. We retrospectively reviewed 137 patients diagnosed with labral tears and FAI or dysplasia (74 or 63 cases, respectively) through an arthroscopic procedure. Labral and concomitant cartilage injuries were evaluated. Demographics and radiological variables [lateral center-edge angle (LCEA), anterior center-edge angle, acetabular index (AI), acetabular version and alpha angle] were evaluated as risk factors for labral and cartilage injuries. Detachment of acetabular cartilage with intact labro-cartilaginous junction was the most common in dysplasia, whereas cartilage delamination from the labro-cartilaginous junction was more common in FAI (P < 0.001). A higher body mass index was significantly associated with delamination injury in FAI (odds ratio 1.226; 95% CI 1.043-1.441; P = 0.013). A significant correlation was evident between detachment injury and a larger AI in dysplasia (odds ratio 1.127; 95% CI 1.000-1.270; P = 0.049). In addition, symptom duration was positively correlated with the extent of labral tearing in FAI (P = 0.013), whereas the smaller LCEA was correlated with the larger extent of labral tearing in dysplasia (P = 0.044). FAI and dysplasia patients exhibited different labral and cartilage injury patterns. Increased body mass index was correlated with delamination injury in FAI, whereas an increased AI was associated with detachment injury in dysplasia. Greater tearing was associated with a longer symptom duration in FAI, and a decreased LCEA was a risk factor for the extent of tearing in dysplasia. Level of evidence Level III. Case-control study.

Progression of Symptomatic Partial-Thickness Rotator Cuff Tears: Association With Initial Tear Involvement and Work Level.

Background: Partial-thickness rotator cuff tears (PTRCTs) often progress to full-thickness rotator cuff tears (FTRCTs). Thus, it is important to analyze the risk factors for tear progression to determine the proper timing of repair. Purpose: To identify the risk factors associated with progression of PTRCT. Study Design: Case-control study; Level of evidence, 3. Methods: Included were 89 patients diagnosed with PTRCT on magnetic resonance imaging (MRI) scans who underwent nonoperative treatment at the authors' institution between August 2012 and August 2019. Patient characteristics, shoulder stiffness (compared with the contralateral shoulder); work level (classified as high [heavy manual labor], medium [manual labor with less activity], and low [sedentary activity]); and radiological factors including initial tear size, acromion type (flat, curved, hooked, or heel-shaped), and initial tear involvement (as a percentage of the rotator cuff tendon footprint length) were analyzed to assess their association with tear progression, defined as >20% increase in tear involvement. Results: The mean MRI follow-up period was 22.3 ± 17.2 months (median, 16.1 months; range, 6.4-89.5 months), and tear progression was observed in 12 patients (13.5%). In these 12 patients, tear involvement increased by 60% of the rotator cuff footprint, while mediolateral (ML) and anteroposterior (AP) tear sizes progressed by 1.1 and 1.8 mm, respectively. Univariate regression analysis showed that shoulder stiffness (P = .031), work level (P = .001), initial tear involvement (P < .001), ML and AP tear sizes (P < .001 and P = .005, respectively), and acromion type (P = .003) were significantly associated with tear progression. Multivariate regression analysis showed that initial tear involvement (odds ratio [OR], 1.053; 95% CI, 1.006-1.102; P = .026) and high work level (OR, 15.831; 95% CI, 1.150-217.856; P = .039) were independent risk factors for tear progression. The cutoff value for initial tear involvement was 47.5% (sensitivity, 81.8%; specificity, 85.7%). Conclusion: Tear progression was observed in 14% of patients with PTRCT in this study. To predict tear progression, evaluating the tear involvement during initial MRI is essential. The risk of tear progression increased with initial tear involvement >47.5% and a heavy work level.

Conservative treatment for brachial plexus injury after a displaced clavicle fracture: a case report and literature review.

BACKGROUND: A brachial plexus injury is a rare complication of clavicle fractures. Previous case reports only examined the surgical outcomes of brachial plexus injuries that occurred after a clavicle fracture and did not report on the outcomes of conservative treatment. In this report, we present the prognosis of a patient with an acute displaced clavicle fracture accompanied by a brachial plexus injury that was conservatively treated. CASE PRESENTATION: A 51-year-old man with a middle-third clavicle fracture due to a direct trauma after falling down the stairs. A brachial plexus injury experienced symptoms, including numbness occurred in the affected upper extremity, at 1 day after the injury. The patient's motor power in the elbow, wrist, and hand decreased at 3 days after the injury. Magnetic resonance imaging (MRI) showed no loss of continuity in the brachial plexus, but showed nerve compression by displaced fracture fragments. Electromyography revealed brachial plexopathy. Conservative treatment, including a shoulder sling, was performed with satisfactory outcomes; the patient reported a 70% improvement at 6 months after the injury. CONCLUSIONS: A brachial plexus injury is a rare complication of clavicle fractures that can cause serious dysfunction of the upper extremities affected by the injury. Conservative treatment may be considered for acute nerve compression by displaced fracture fragments rather than extensive callus or granulation tissue formation to achieve a satisfactory recovery in young patients. MRI should typically be performed before making a treatment decision to examine the brachial plexus for any discontinuity or kinking.

Rapidly destructive osteonecrosis of the humeral head after arthroscopic rotator cuff repair: a case report.

BACKGROUND: Cases of rapidly destructive osteonecrosis (RDON) of the humeral head after arthroscopic rotator cuff repair (RCR) have rarely been reported, which has prevented a clear consensus on the cause of osteonecrosis. CASE PRESENTATION: A 63-year-old woman without a history of trauma underwent arthroscopic RCR after being diagnosed with a medium-sized full-thickness rotator cuff tear for symptoms of left shoulder pain for six months. The patient had no medical history other than hypertension, and no other potential cause was found for osteonecrosis of the left shoulder prior to surgery. Four months after surgery, pain and range of motion improved. Six months after surgery, the patient complained of an increase in shoulder pain. While follow-up ultrasonography did not show a re-tear of the repaired tendon, osteonecrosis of the humeral head could not be confirmed as plain radiography was not performed. Follow up MRI performed a year after surgery revealed RDON of the humeral head. Despite mild improvement in the shoulder pain, the Shoulder Rating Scale of the University of California at Los Angeles (UCLA) and Constant score were poor at 23 and 69, respectively. In the present case, the arthroscopic RCR was performed using two anchors; for the repair of the anterior of the supraspinatus and the rotator interval, a 2.8-mm all-suture anchor was inserted into the upper part of the intertubercular groove. The cause of RDON is presumed to be the damage to the anterolateral and intraosseous branches of the anterior humeral circumflex artery (AHCA) for anchor positioning and insertion. CONCLUSIONS: A poor outcome was obtained in the case of RDON, despite the integrity of the repaired rotator cuff tendon after arthroscopic RCR was intact. Although the cause of RDON has not been clearly established, care should be taken not to damage the anterolateral and intraosseous branches of the AHCA regarding the insertion location of the suture anchor, and to prepare the anchor in the vicinity of the intertubercular groove.

Risk Factors for Non-Union after Open Reduction and Internal Fixation in Patients with Distal Humerus Fractures.

BACKGROUND: Only a few studies have reported on the risk factors for non-union after open reduction and internal fixation (ORIF) in distal humerus fractures. METHODS: We retrospectively reviewed 155 patients who underwent ORIF for distal humerus fractures from January 2008 to June 2020. Various patient factors, including body mass index (BMI), diabetes mellitus (DM), and combined fracture, as well as surgical factors, including fixation methods (e.g., orthogonal plate/parallel plate/single plate/tension bend wiring [TBW]) and combined fracture operations, were evaluated as risk factors for non-unions. RESULTS: Among the patient factors, BMI (25.0 ± 3.4 vs. 22.7 ± 3.4, p = 0.032), DM (5/13 [38.5%] vs. 20/142 [14.1%], p = 0.038) and combined fracture (5/13 [38.5%] vs. 16/142 [11.3%], p = 0.018) were significantly different between groups with non-union and union. Among the surgical factors, combined fracture operation (5 [38.5%] vs. 9 [6.3%], p = 0.002) and the fixation method (3 [23.1%]/1 [7.7%]/4 [30.8%]/5 [38.5%] vs. 84 [59.2%]/7 [4.9%]/40 [28.2%]/11 [7.7%], p = 0.005) showed a significant difference between groups with non-union and union. Multivariate regression analysis showed that combined fracture operation (OR 10.467; 95% CI 1.880-58.257; p = 0.007) and TBW (OR 9.176; 95% CI 1.474-57.135; p = 0.018) among the fixation methods posed as a significant risk factor for non-union. CONCLUSIONS: The risk of non-union increased in patients who underwent surgery for another fracture combined with distal humerus fracture and in patients who underwent ORIF with TBW.

Perianchor cyst formation in all-suture anchor after rotator cuff repair: an evaluation of anchor insertion angle.

BACKGROUND: Previous studies reported that micromotion after all-suture anchor implantation can lead to perianchor cyst formation (PCF), leading to risk of retear. Modifying anchor insertion angle (AIA) is known to be one of the various ways to increase anchor stability. However, there currently are few studies that assess the correlation between PCF, AIA, and retear. PURPOSE: To find the correlation of PCF and the repaired rotator cuff integrity with AIA after arthroscopic double-row suture-bridge rotator cuff repair (RCR) using an all-suture anchor in the medial row. METHODS: A total of 218 patients who underwent arthroscopic double-row suture-bridge RCR were retrospectively reviewed. All patients underwent RCR using all-suture anchors and polyether ketone anchors in the medial and lateral rows, respectively. Magnetic resonance imaging was conducted 6 months after the surgery to evaluate PCF, AIA, and integrity of the repaired cuff. The all-suture anchor insertion angle in the medial row was measured with reference to the greater tuberosity to assess the relationship between the AIA and PCF. The correlations between PCF, AIA, and post-RCR integrity were evaluated including various demographic and radiologic factors. RESULTS: Perianchor cysts were formed in 93 patients (42.7%). Mediolateral tear size (2.1 ± 1.2 cm vs. 1.7 ± 0.9 cm, P = .034) and AIA (61.9° ± 15.2° vs. 68.4° ± 13.0°, P = .001) were significantly different between patient groups with and without perianchor cysts. Multivariate logistic regression analysis showed that mediolateral tear size (odds ratio [OR] 1.318, 95% confidence interval [CI] 1.008-1.724; P = .043) and AIA (OR 0.967, 95% CI 0.947-0.988; P = .002) were independent risk factors for PCF. In addition, PCF was observed more frequently (69.6% vs. 32.1%, P < .001) and the AIA was lower (59.4° ± 13.7° vs. 67.8° ± 13.8°, P < .001) in the retear group than in the healed group. CONCLUSIONS: Perianchor cysts were formed in approximately 40% of patients who underwent arthroscopic double-row suture-bridge RCR using all-suture anchors. Low AIA and large mediolateral tear size were risk factors for PCF. Moreover, perianchor cyst and AIA were correlated with post-RCR integrity. Therefore, a high AIA must be carefully considered when all-suture anchors are inserted into the medial row when performing RCR.

Risk factors for increased perioperative blood loss during total knee arthroplasty in patients with haemophilia.

INTRODUCTION: Currently, there is a paucity of literature describing the risk factors for increased perioperative blood loss (PBL) during total knee arthroplasty (TKA) in haemophilia. Furthermore, no studies have analysed coagulation factor levels that affect PBL. AIM: To identify the risk factors for increased PBL by incorporating coagulation factor levels following TKA in patients with haemophilic arthropathy. METHODS: A total of 92 TKA (78 haemophilia A and 14 haemophilia B) were performed for haemophilic arthropathy. PBL was calculated using the haemoglobin (Hb) balance method, and patients were categorised into two groups: group H (higher blood loss than the mean PBL, n = 36) and group L (lower blood loss than the mean PBL, n = 56). Body mass index (BMI), operation day Hb, haematocrit and coagulation factor level (VIII or IX) were analysed, including demographic and laboratory data. RESULTS: The mean PBL volume during TKA for haemophilic arthropathy of the knee was 542.3 ± 361.7 mL. Multivariate analysis revealed that lower haematocrit on the operation day (odds ratio [OR], .633; 95% confidence interval [CI], .511-.786; p < .001) and coagulation factor level (OR .970, CI .941-.999; p = .046) were independent risk factors for increased PBL. Receiver-operating characteristic analysis identified these cutoff values for predicting increased PBL: operation day coagulation factor level 93.5% (sensitivity, 70.4%; specificity, 67.6%) and haematocrit level of 38.2% (sensitivity, 85.7%; specificity, 80.6%). CONCLUSIONS: The PBL increased as haematocrit and coagulation factor levels decreased on the operation day. A coagulation factor level <93.5% or haematocrit level of <38.2% may be a significant risk factor for increasing PBL. LEVEL OF EVIDENCE: Level IV, Case Series, Treatment Study.

Comparison of supraclavicular nerve injuries after clavicle mid-shaft surgery via minimally invasive plate osteosynthesis versus open reduction and internal fixation.

INTRODUCTION: Only a few previous studies have evaluated the factors related to supraclavicular nerve (SCN) injury after clavicle mid-shaft fracture surgery. We analyzed the frequency and risk factors for SCN injury after clavicle mid-shaft fracture surgery via open reduction and internal fixation (ORIF) versus minimally invasive plate osteosynthesis (MIPO) MATERIALS AND METHODS: We retrospectively reviewed the cases from 59 patients who had undergone surgery for clavicle mid-shaft fractures between January 2018 and April 2019. Twenty-nine patients had undergone ORIF and 30 had undergone MIPO. The frequency of SCN injury in the two groups was evaluated, and preoperative patient demographics (age, sex, body mass index, smoking, alcohol, diabetes mellitus, and trauma mechanism), and radiological parameters (fracture displacement and shortening) were measured and evaluated as risk factors for SCN injury. When neurological symptoms, such as numbness, were present on the anterior chest wall or at the incision site, electromyography (EMG) was conducted. RESULTS: Neurological symptoms were present in 12 patients. Numbness in the anterior upper chest around the incision site was present in eight and four patients who underwent ORIF and MIPO, respectively (p < 0.001). Furthermore, fracture displacement evaluated on preoperative three-dimensional computed tomography was significantly associated with the occurrence of SCN injury in patients who underwent MIPO (odds ratio, 1.038; 95% confidence interval, 1.001-1.077; p = 0.047). Although EMG was conducted in all patients with SCN injury, peripheral neuropathy was not found in any cases. CONCLUSIONS: SCN injury, which is a possible complication of clavicle mid-shaft fracture surgery, occurred significantly less frequently in MIPO than in ORIF. In MIPO, greater preoperative fracture displacement was associated with a higher risk of SCN injury. Additional studies are required to reach a consensus regarding accurate methods to evaluate SCN injuries. LEVEL OF EVIDENCE: IV, case series, treatment study.

Optimal concentration of mesenchymal stem cells for fracture healing in a rat model with long bone fracture.

BACKGROUND: There is still no consensus on which concentration of mesenchymal stem cells (MSCs) to use for promoting fracture healing in a rat model of long bone fracture. AIM: To assess the optimal concentration of MSCs for promoting fracture healing in a rat model. METHODS: Wistar rats were divided into four groups according to MSC concentrations: Normal saline (C), 2.5 × 106 (L), 5.0 × 106 (M), and 10.0 × 106 (H) groups. The MSCs were injected directly into the fracture site. The rats were sacrificed at 2 and 6 wk post-fracture. New bone formation [bone volume (BV) and percentage BV (PBV)] was evaluated using micro-computed tomography (CT). Histological analysis was performed to evaluate fracture healing score. The protein expression of factors related to MSC migration [stromal cell-derived factor 1 (SDF-1), transforming growth factor-beta 1 (TGF-ß1)] and angiogenesis [vascular endothelial growth factor (VEGF)] was evaluated using western blot analysis. The expression of cytokines associated with osteogenesis [bone morphogenetic protein-2 (BMP-2), TGF-ß1 and VEGF] was evaluated using real-time polymerase chain reaction. RESULTS: Micro-CT showed that BV and PBV was significantly increased in groups M and H compared to that in group C at 6 wk post-fracture (P = 0.040, P = 0.009; P = 0.004, P = 0.001, respectively). Significantly more cartilaginous tissue and immature bone were formed in groups M and H than in group C at 2 and 6 wk post-fracture (P = 0.018, P = 0.010; P = 0.032, P = 0.050, respectively). At 2 wk post-fracture, SDF-1, TGF-ß1 and VEGF expression were significantly higher in groups M and H than in group L (P = 0.031, P = 0.014; P < 0.001, P < 0.001; P = 0.025, P < 0.001, respectively). BMP-2 and VEGF expression were significantly higher in groups M and H than in group C at 6 wk post-fracture (P = 0.037, P = 0.038; P = 0.021, P = 0.010). Compared to group L, TGF-ß1 expression was significantly higher in groups H (P = 0.016). There were no significant differences in expression levels of chemokines related to MSC migration, angiogenesis and cytokines associated with osteogenesis between M and H groups at 2 and 6 wk post-fracture. CONCLUSION: The administration of at least 5.0 × 106 MSCs was optimal to promote fracture healing in a rat model of long bone fractures.

Antegrade Intramedullary Fixation for Clavicular Shaft Fracture: A Technical Trick.

SUMMARY: The standard open reduction and internal fixation technique with a plate and screws for a simple mid shaft clavicular fracture necessitates a relatively large incision and can also lead to variable amount of keloid scar formation. Historically, other techniques of more minimally invasive retrograde intramedullary fixation with the entry point posterolaterally on the shoulder have shown their own disadvantages and complications. We present a surgical technique of antegrade intramedullary fixation for mid shaft clavicular fractures and an illustrative case series.