Rotator cuff repairs with all-suture tape anchors: no difference in outcomes between with or without all-suture tape anchors.

PURPOSE: This study aimed at comparing the outcomes of medium- to large-sized rotator cuff repairs performed using the suture bridge technique either with or without tape-like sutures, and single row techniques with conventional sutures. METHODS: A total of 135 eligible patients with medium to large rotator cuff tears were identified and analyzed retrospectively, from 2017 to 2019. Only repairs using all-suture anchors were included in the study. Patients were divided into the following three groups: single-row (SR) repair (N = 50), standard double-row suture bridge (DRSB) repair with conventional sutures (N = 35), and DRSB with tape-like sutures (N = 50). The average postoperative follow-up period was 26.3 ± 9.8 months (range, 18-37). RESULTS: DRSB with tapes had the highest re-tear rate of 16% (8/50), but there was no significant difference with the re-tear rates observed in SR (8%, 4/50) and DRSB with conventional sutures (11.4%, 4/35) (n.s.). DRSB with tapes demonstrated higher rate of type 2 re-tears (10%) compared to type 1 re-tears (6%), but the other two groups showed either similar or higher rates of type 1 re-tears compared to that of type 2. Post-operative functional scores of the three groups improved significantly (all p < 0.05), but the differences between the groups were not statistically significant. CONCLUSIONS: No clinical difference in functional outcomes and re-tear rates were observed in DRSB with tapes when compared with SR and DRSB using the conventional sutures. Tape-like DRSB suture which was expected to be superior by its biomechanical advantage was clinically non-superior to conventional DRSB suture. There were no significant differences in VAS scores and UCLA scores. LEVEL OF EVIDENCE: Level III.

Subacromial notching after reverse total shoulder arthroplasty.

BACKGROUND: Scapular notching is a well-known postoperative complication of reverse total shoulder arthroplasty (RTSA). However, subacromial notching (SaN), a subacromial erosion caused by repeated abduction impingement after RTSA, has not been previously reported in a clinical setting. Therefore, this study aimed to assess the risk factors and functional outcomes of SaN after RTSA. METHODS: We retrospectively reviewed the medical records of 125 patients who underwent RTSA with the same design between March 2014 and May 2017 and had at least 2 years of follow-up. SaN was defined as subacromial erosion observed at the final follow-up but not on the X-ray 3 months after surgery. Radiologic parameters representing the patient's native anatomy and degrees of lateralization and/or distalization during surgery were evaluated using preoperative and 3 months postoperative X-rays. The visual analogue scale of pain, active range of motion, and American Shoulder and Elbow Surgeons score were assessed preoperatively and at the final follow-up to evaluate the functional outcomes of SaN. RESULTS: SaN occurred in 12.8% (16/125) of enrolled patients during the study period. Preoperative center of rotation-acromion distance (P = .009) and postoperative humerus lateralization offset, which evaluated the degree of lateralization after RTSA (P = .003), were risk factors for SaN. The preoperative center of rotation-acromion distance and postoperative humerus lateralization cutoff values were 14.0 mm and 19.0 mm, respectively. The visual analogue scale of pain (P = .01) and American Shoulder and Elbow Surgeons score (P = .04) at the final follow-up were significantly worse in patients with SaN. CONCLUSIONS: SaN might adversely affect postoperative clinical outcomes. As SaN correlated with patients' anatomical characteristics and degree of lateralization during RTSA, the implant's degree of lateralization should be adjusted according to the patient's own anatomical characteristics.

The correlation of the spinoglenoid ganglion cyst size with the electrophysiological alterations of suprascapular nerve and the rotator cuff muscle power.

BACKGROUND: Although various treatment options are available for spinoglenoid cyst, including conservative and surgical methods, there is no standard guideline for its surgical decompression. Thus, the purpose of the study was to correlate the size of the spinoglenoid notch ganglion cyst (GC) as revealed by magnetic resonance imaging (MRI) with electrophysiological alterations, muscle power, and pain severity, and to estimate a cut-off value of cyst size to perform a decompression. METHODS: Between January 2010 and January 2018, the patients with a GC at the spinoglenoid notch diagnosed on MRI, and who had a minimum follow-up of 2 years after the decompression were included. Maximum cyst diameter as measured on MRI was used for comparison. Electromyography (EMG) and nerve conduction velocity (NCV) studies were performed before the surgery. Peak torque deficit (PTD) percentage compared to opposite shoulder was calculated preoperatively and at 1 year after surgery. Pain severity was estimated using visual analogue scale (VAS) preoperatively. RESULTS: Ten (50%) of 20 patients with GC > 2.2 cm and 1 (5.9%) of 17 patients with GC < 2.2 cm showed EMG/NCV abnormalities (p = 0.019). There was a correlation between the cyst size and the positive EMG/NCV findings (Correlation coefficient (CC) = 0.535, p < 0.001). The preoperative peak torque deficit on the external rotation was correlated with the positive EMG/NCV findings (CC = 0.373, p = 0.021). The PTD was improved significantly at 1 year postoperatively in patients with a GC size >2.2 cm (p = 0.029). The cyst size was not related to the preoperative pain VAS and muscle power. CONCLUSIONS: The spinoglenoid cyst size >2.2 cm, but not pain severity or muscle power, correlates with the positive finding of EMG for compressive suprascapular neuropathy. The GC size >2.2 cm can be a reference to decide the need of decompression surgery. LEVEL OF EVIDENCE: IV, case series.

Long-term outcomes after humeral head replacement and total shoulder replacement for osteonecrosis of the humeral head: a mean follow-up of 8 years.

INTRODUCTION: The purpose of this study was to compare the outcomes and complications after humeral head replacement (HHR) and total shoulder replacement (TSR) in patients with osteonecrosis of the humeral head (ONHH). MATERIALS AND METHODS: Twenty-six patients who underwent shoulder replacement (13 HHRs and 13 TSRs) for nontraumatic ONHH were included. The mean follow-up period was 96.4 months. The visual analog scale (VAS) pain score, the University of California at Los Angeles (UCLA) score, the American Shoulder and Elbow Surgeon (ASES) score, and range of motion (ROM) at the final follow-up evaluation were used for the assessment of clinical outcomes. RESULTS: The mean VAS pain score, UCLA score, and ASES score showed significant improvement from 6.3, 11.6, and 35.0 before surgery to 2.2, 28.9, and 82.6 at the final follow-up evaluation (all p < 0.001). No significant differences regarding all clinical scores and ROMs were observed between the HHR group and the TSR group, except that a greater abduction angle was observed in the HHR group compared with the TSR group (123.1° versus 96.9°, p = 0.014). Two patients in the TSR group underwent multiple reoperations due to periprosthetic joint infection. No revision surgeries were performed for glenoid erosion following HHR or aseptic glenoid loosening following TSR. CONCLUSIONS: The findings of this study showed satisfactory clinical and radiological outcomes with implant longevity for both HHR and TSR in patients with nontraumatic ONHH. The HHR group had a greater abduction angle compared with the TSR group.

Comprehensive and critical evaluation of individualized pathway activity measurement tools on pan-cancer data.

MOTIVATION: Biological pathways are extensively used for the analysis of transcriptome data to characterize biological mechanisms underlying various phenotypes. There are a number of computational tools that summarize transcriptome data at the pathway level. However, there is no comparative study on how well these tools produce useful information at the cohort level, enabling comparison of many samples or patients. RESULTS: In this study, we systematically compared and evaluated 13 different pathway activity inference tools based on 5 comparison criteria using pan-cancer data set. This study has two major contributions. First, our study provides a comprehensive survey on computational techniques used by existing pathway activity inference tools. The tools use different strategies and assume different requirements on data: input transformation, use of labels, necessity of cohort-level input data, use of gene relations and scoring metric. Second, we performed extensive evaluations on the performance of these tools. Because different tools use different methods to map samples to the pathway dimension, the tools are evaluated at the pathway level using five comparison criteria. Starting from measuring how well a tool maintains the characteristics of original gene expression values, robustness was also investigated by adding noise into gene expression data. Classification tasks on three clinical variables (tumor versus normal, survival and cancer subtypes) were performed to evaluate the utility of tools for their clinical applications. In addition, the inferred activity values were compared between the tools to see how similar they are along with the scoring schemes they use.

The scissors sign: a provocative test for detecting the leading-edge tear of subscapularis tendon: a diagnostic study.

BACKGROUND: Several physical examination tests and signs have been described to aid in the diagnosis of subscapularis (SSC) tear, but have limitations and variable sensitivity. This study aimed to introduce a novel test for detecting a leading-edge tear of the subscapularis (LETS), the most important tendinous portion of SSC. METHODS: A total of 233 patients who underwent arthroscopic repair for anterior and superior cuff tears between January 2018 to September 2019 were retrospectively reviewed. The provocative test we have coined as the "scissors sign" and the other related clinical tests (i.e., belly press, belly off, Napoleon, lift off, internal rotation lag, bear hug tests) were performed preoperatively. Whether the patient has a LETS or the complete tear of the SSC (CTS) was confirmed by arthroscopic findings. Sensitivity, specificity, and areas under the receiver operating characteristic curve were calculated for each test. RESULTS: In patients who had LETS with or without supraspinatus tear, the scissors sign showed the highest sensitivity (91.4%) with a specificity of 81.6%, positive predictive value (PPV) of 80.2%, and negative predictive value (NPV) of 92.1%. In patients with isolated LETS, the scissors sign also showed the highest sensitivity (90.3%) with a specificity of 81.6%, PPV of 57.1%, and NPV of 96.8%. The scissors sign for the complete tear of the subscapularis (CTS) with or without supraspinatus tear and the isolated CTS had a sensitivity of 73.1 and 75%, respectively. CONCLUSIONS: The scissors sign is a novel provocative test that can be helpful in the diagnosis of subscapularis tears, especially LETS, with its high sensitivity and diagnostic accuracy. In combination with other tests, the scissors sign will be a good screening tool.

Retear After Arthroscopic Rotator Cuff Repair Results in Functional Outcome Deterioration Over Time.

PURPOSE: This study aimed to evaluate the effect of retear on long-term functional outcomes and glenohumeral joint osteoarthritis (OA) progression after arthroscopic rotator cuff repair (ASRCR). METHODS: We retrospectively reviewed 201 patients who underwent ASRCR and were followed up for at least 5 years. Rotator cuff tendon structural integrity was evaluated using magnetic resonance imaging and/or ultrasonography. Pain, active range of motion, and the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) were evaluated for functional outcomes. To evaluate deterioration over time, the minimal clinically important difference value of pain and ASES were used. RESULTS: The mean follow-up period was 8.6 ± 2.2 years and overall retear rate was 21.4%. OA progression was strongly associated with retear (odds ratio 5.1, P < .001). Functional outcomes at the 2-year postoperative follow-up significantly improved compared to the preoperative status (all P < .017), regardless of retear. However, the retear group presented worse functional outcomes at the final follow-up (pain: 3.1 ± 2.6; ASES: 72.0 ± 17.4) than at the 2-year postoperative follow-up (pain: 1.2 ± 2.3, P = .014; ASES: 91.1 ± 9.9, P= .015) than the healed tendon group at final follow-up (pain: .6 ± 1.7; P < .001; ASES 95.5 ± 11.8; P < .001). The time for deterioration of pain (healed group vs. retear group: 5.5 ± 0.5 vs. 10.6 ± 0.4 years; P < .001) and ASES (healed group vs. retear group: 7.5 ± 0.5 vs. 12.8 ± 0.2 years; P < .001) decreased in the retear group. CONCLUSIONS: The functional status improved after ASRCR in short- and long-term follow-up, regardless of retear. However, retear was strongly associated with OA progression, and long-term functional outcomes deteriorated over time in retear cases, which was not observed during short-term follow-up. STUDY DESIGN: III, retrospective cohort study.

Allogeneic Dermal Fibroblasts Improve Tendon-to-Bone Healing in a Rabbit Model of Chronic Rotator Cuff Tear Compared With Platelet-Rich Plasma.

PURPOSE: To compare the effects of allogeneic dermal fibroblasts (ADFs) and platelet-rich plasma (PRP) on tendon-to-bone healing in a rabbit model of chronic rotator cuff tear. METHODS: Thirty-two rabbits were divided into 4 groups (8 per group). In 2 groups, the supraspinatus tendon was detached and was left as such for 6 weeks. At 6 weeks after creating the tear model, we performed transosseous repair with 5 × 106 ADFs plus fibrin injection in the left shoulder and PRP plus fibrin in the right shoulder. The relative expression of the COL1, COL3, BMP2, SCX, SOX9, and ACAN genes was assessed at 4 weeks (group A) and 12 weeks (group B) after repair. Histologic and biomechanical evaluations of tendon-to-bone healing at 12 weeks were performed with ADF injection in both shoulders in group C and PRP injection in group D. RESULTS: At 4 weeks, COL1 and BMP2 messenger RNA expression was higher in ADF-injected shoulders (1.6 ± 0.8 and 1.0 ± 0.3, respectively) than in PRP-injected shoulders (1.0 ± 0.3 and 0.6 ± 0.3, respectively) (P = .019 and P = .013, respectively); there were no differences in all genes in ADF- and PRP-injected shoulders at 12 weeks (P > .05). Collagen continuity, orientation, and maturation of the tendon-to-bone interface were better in group C than in group D (P = .024, P = .012, and P = .013, respectively) at 12 weeks, and mean load to failure was 37.4 ± 6.2 N/kg and 24.4 ± 5.2 N/kg in group C and group D, respectively (P = .015). CONCLUSIONS: ADFs caused higher COL1 and BMP2 expression than PRP at 4 weeks and showed better histologic and biomechanical findings at 12 weeks after rotator cuff repair of the rabbit model. ADFs enhanced healing better than PRP in the rabbit model. CLINICAL RELEVANCE: This study could serve as a transitional study to show the effectiveness of ADFs in achieving tendon-to-bone healing after repair of chronic rotator cuff tears in humans.

Medialized vs. lateralized humeral implant in reverse total shoulder arthroplasty: the comparison of outcomes in pseudoparalysis with massive rotator cuff tear.

BACKGROUND: With the increasing use of lateralized humeral implants in reverse total shoulder arthroplasty (RTSA), it is still unclear whether this design will be as advantageous as the medialized humeral implants in the setting of pseudoparalysis (PP). METHODS: A total of 51 eligible RTSA cases for PP signs due to massive rotator cuff deficiency were selected for the retrospective review. Twenty-five patients were allocated to group L in which the isolated humeral side lateralization was performed (neck-shaft angle of 145°), and 26 patients were allocated to group M (neck-shaft angle of 155°). Pre- and postoperative radiologic measurements including critical shoulder angle, acromiohumeral distance (AHD), lateral humeral offset (LHO), and deltoid wrapping offset (DWO), as well as range of motion (ROM) and clinical outcome scores, were compared. The mean age was 71.0 ± 6.5 years for group L and 70.3 ± 7.0 years for group M, and the overall mean follow-up period was 49.0 ± 13.5 months (range, 25.7-68.9). RESULTS: The preoperative radiologic measurements were similar, but the postoperative LHO and DWO were significantly larger for group L, whereas the postoperative AHD was larger for group M compared with group L, with the values being 39.8 ± 9.7 mm and 33.6 ± 10.4 mm, respectively (P = .034). For the ROM, active forward elevation did improve significantly for both, starting preoperatively with the active ranges of 39° ± 19° (passively 153° ± 24°) for group L and 42° ± 18° (passively 156° ± 11°) for group M-the final postoperative active ranges being 142° ± 16° and 133° ± 33°, respectively, without significant difference between the groups (P = .426). The postoperative recovery of PP for group L was 100% (25 of 25), whereas for group M, it was 96.2% (25 of 26). The final visual analog scale (VAS) scores and University of California Los Angeles (UCLA) shoulder scores improved significantly for both groups, but the differences between the groups at the final assessments were insignificant. The 4 complications were periprosthetic fracture, acromial stress fracture, periprosthetic joint infection, and neuropraxia, all of which were in group M, and scapular notching with higher grades were more prevalent for group M (26.9%, 7 of 26). CONCLUSIONS: With RTSA, good outcomes and recovery were achieved in most cases of PP. The postoperative active elevation range and functional outcomes were not affected by medialization or lateralization of the humeral implant. Earlier recovery of motion was observed with the lateralized group, but no significant differences were seen in the final ROM between the groups.

Logic-based analysis of gene expression data predicts association between TNF, TGFB1 and EGF pathways in basal-like breast cancer.

For breast cancer, clinically important subtypes are well characterized at the molecular level in terms of gene expression profiles. In addition, signaling pathways in breast cancer have been extensively studied as therapeutic targets due to their roles in tumor growth and metastasis. However, it is challenging to put signaling pathways and gene expression profiles together to characterize biological mechanisms of breast cancer subtypes since many signaling events result from post-translational modifications, rather than gene expression differences. We designed a logic-based computational framework to explain the differences in gene expression profiles among breast cancer subtypes using Pathway Logic and transcriptional network information. Pathway Logic is a rewriting-logic-based formal system for modeling biological pathways including post-translational modifications. Our method demonstrated its utility by constructing subtype-specific path from key receptors (TNFR, TGFBR1 and EGFR) to key transcription factor (TF) regulators (RELA, ATF2, SMAD3 and ELK1) and identifying potential association between pathways via TFs in basal-specific paths, which could provide a novel insight on aggressive breast cancer subtypes. Codes and results are available at http://epigenomics.snu.ac.kr/PL/.

Biceps Rerouting for Semirigid Large-to-Massive Rotator Cuff Tears.

PURPOSE: To compare clinical and radiographic results of arthroscopic rotator cuff repair (ARCR) with biceps rerouting (BR) and those of conventional repair for semirigid, large-to-massive rotator cuff tear. METHODS: We prospectively collected data of 111 patients who underwent either ARCR + BR (n = 59, group 1) or only ARCR (n = 52, group 2) for semirigid, large-to-massive rotator cuff tear between January 2016 and December 2018. We comparatively analyzed both groups with respect to preoperative factors including concomitant lesions of the long head of the biceps tendon (LHBT). Univariate logistic regression analysis was performed to identify predictive variables for occurrence of retear after ARCR + BR. RESULTS: Mean age of groups 1 and 2 were 62.8 and 63.7 years, respectively (P = .484). Mean follow-up period in groups 1 and 2 were 15.1 and 25.1 months, respectively (P = .102). Mean range of motion and functional scores improved significantly (P < .05) and comparably (P > .05) in both groups. In total, 11 (18.6%) and 25 (48.1%) patients from groups 1 and 2, respectively, showed retear of the repaired rotator cuff at final follow-up (P < .01). Of 45 group 1 patients who showed less than 50% partial tearing of the LHBT preoperatively, 6 (13.3%) experienced retear. Comparatively, of 14 patients with partial tearing involving more than 50% of the LHBT, 5 (35.7%) suffered postoperative retear. If the patients had partial tear involving more than 50% of LHBT preoperatively, the odds ratio (OR) to have retear was 4.222 (P = .037). Wider (OR, 1.445, P = .047) and thinner (OR, 0.166, P = .019) LHBT were the prognostic factors to have retear. Three (5.1%) group 1 patients showed the Popeye deformity at final follow-up. CONCLUSIONS: ARCR + BR for semirigid, large-to-massive rotator cuff tears effectively improved clinical and structural outcomes as also shown in the conventional repairs. However, the retear rate was significantly lower in patients who underwent ARCR + BR than those treated conventionally. Partial tearing involving more than 50% of the LHBT and wide and/or thin tendon morphology were significant risk factors for postoperative occurrence of retear. LEVEL OF EVIDENCE: Level III, retrospective therapeutic comparative trial.

Retracted Rotator Cuff Repairs Heal With Disorganized Fibrogenesis Without Affecting Biomechanical Properties: A Comparative Animal Model Study.

PURPOSE: To determine the differences in the scar tissue formation during the healing of the repaired retracted cuff tear from that of the nonretracted tear. METHODS: Eighteen right rabbit shoulders received a 1-cm transverse cuff incision over the footprint to simulate "nonretracted cuff tears" before the transosseous repairs (group A). A 1-cm tendinous portion was excised from 18 left shoulders to create defects to simulate "retracted cuff tears" before repairing the defects (group B). At week 12 postrepair, 20 and 16 shoulders underwent histologic and biomechanical analyses, respectively. Eight shoulders were used as a control group for biomechanical analyses. RESULTS: All specimens showed good healing and continuity of the repaired tendons. At low magnification, fibrous tissue firmly held the tendon-to-bone junctions in group A; however, all specimens in group B showed medially retracted tendons with fibrous tissue continuity between the tendon stumps and footprints. At medium magnification, more irregular collagen fiber orientation was observed in group B. Polarized light microscopy showed fibrous tissue continuity with medially retracted tendons in group B. When we quantified collagen fiber orientation using ImageJ software, group B had inferior grayscale measurements when compared with group A (P = .001). At week 12, no statistical differences existed in mean loads-to-failure at the repair sites between the groups (P = .783). CONCLUSIONS: In the nonretracted cuff tears, fibrous tissue bound the tendon-to-bone junction with healing. After the healing of the retracted cuff tears, continuity of nontendinous tissue was observed adjacent to the medially retracted tendon, which comprised more disorganized immature fibrous tissue than that in the nonretracted cuff tears. CLINICAL RELEVANCE: Unlike the healing of nonretracted rotator cuff tear, repairing of the "retracted" tendon end of cuff tear still resulted in retraction of the tendon back to its original position but being held down with fibrous tissue to the footprint.

Hematologic Expression After Shoulder Surgery: Normalization Curve of Serum Inflammatory Markers.

PURPOSE: To determine the normalization curves of the serologic markers including white blood cell (WBC) count, WBC differential for segmented neutrophil (WBC seg.), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) after elective shoulder surgery and to investigate the hematologic differences among different shoulder surgeries. METHODS: Seventy-seven patients underwent arthroscopic rotator cuff repair (RCR, group A), 44 patients had open rotator cuff repair (group B), and 84 patients had shoulder arthroplasty (group C). Peak and normalization times of markers were determined at preoperatively, postoperative day (POD) 1 and 2 days, 1 and 2 weeks, 1, 2, 3, 6 months, and 1 year after surgery. The normal ranges of serologic markers were set to WBC 4000 to10,000/µL, WBC seg. 40% to 60%, ESR 0 to 20 mm/h, and CRP 0 to 0.8 mg/dL. RESULTS: Groups reached peak mean WBC count and WBC seg. on POD 1; mean WBC count started decreasing on POD 2 but was within normal value afterwards. Mean WBC seg. decreased to normal value at 1 month postoperatively in group A and B and at 2 months postoperatively in group C. Mean ESR peaked at 2 weeks postoperatively and normalized after 1 month in groups A and B and 3 months in group C. Mean CRP levels peaked on POD 2 in all groups and normalized within 2 weeks postoperatively in groups A and B and 1 month postoperatively in Group C. Normalized values of WBC count, WBC seg., and ESR varied widely. In contrast, CRP showed a consistent undetectable median, upper and lower quartile values less than 0.5 after normalization. Mean serum ESR and CRP values at peak time were significantly greater in group C than in the other groups (P = .001). CONCLUSIONS: The mean CRP levels were normalized at 2 weeks after rotator cuff repair and at 1 month after arthroplasties. Unlike the other serologic markers, CRP had consistent normalized values of median, upper and lower quartile afterwards. The peak levels of the inflammatory markers were greater and therefore normalized slower following more invasive surgery. LEVEL OF EVIDENCE: Level III, case control study.

Nontendinous healing after repairing of retracted rotator cuff tear: an imaging study.

BACKGROUND: Follow-up magnetic resonance imaging (MRI) after rotator cuff repair can sometimes demonstrate healing with nontendinous tissue that extends from the footprint to the retracted tendon end, which is inferred as fibrous tissue formation. The aim was to investigate this particular finding and its significance. METHODS: There were 494 eligible cases of healed supero-posterior medium-sized to massive rotator cuff repairs, after the exclusion of retears. A retrospective review was performed for the 3 groups that were divided according to their MRI appearances of healing: type I described the direct healing of the tendon to the footprint, whereas type II demonstrated the distinctive continuity of nontendinous tissue from the footprint to the retracted tendinous portion, and type III also showed a similar appearance but with obvious thinning of the tissue, without any evidence of defect confirmed on the routine outpatient ultrasonograph. RESULTS: Only 108 of 494 patients (21.9%) demonstrated type I healing, whereas the signs of nontendinous healing were evident for the rest, with the 116 patients (23.5%) being classified as type III with attenuation. Comparing the preoperative tendon retraction, 34.8% and 37.2% of the Patte stages 2 and 3, respectively, resulted in type III healing, which were significantly higher compared with that of stage 1 (15.3%, P < .001). Type III healing had the highest average preoperative Goutallier grades. The average postoperative visual analog scale and the American Shoulder and Elbow Surgeons (ASES) scores have improved significantly for all 3 groups (P < .05), with the ASES score being 86.1±15.9 for type I, 93.7±36.1 for type II, and 87.8±15.1 for type III without significant differences between the groups (P = .3). CONCLUSIONS: Only a fifth of the rotator cuff repairs led to a direct healing to the footprint, and the rest healed with MRI appearance of nontendinous tissue formation bridging the retracted tendinous portion and the footprint. These MRI appearances did not represent the true tendinous tissue formation between the torn end of the tendon and the bone after healing. Such appearances did not seem to affect the clinical outcomes.

Risk factors for and prognosis of folded rotator cuff tears: a comparative study using propensity score matching.

BACKGROUND: The prognosis of rotator cuff repair (RCR) may be affected by the shape and quality of the torn rotator cuff tendon. However, only a few studies have reported on folded rotator cuff tears (FCTs). Therefore, this study aimed to evaluate the prognostic factors for FCT and clinical outcomes of FCT repair. METHODS: Through propensity score matching (PSM), 200 (40 patients with FCTs and 160 controls) of 1927 patients who underwent RCR from 2010 to 2016 were included. The variables not used for PSM were compared. The anatomic and functional outcomes were assessed at the final follow-up (32.3 ± 21.2 months), and the related prognostic factors for FCTs were evaluated. RESULTS: The risk factors for FCT were heel-type spur (odds ratio [OR], 11.6; P < .001) and delamination (OR, 2.3; P = .034). Although the functional scores at the final follow-up for both groups improved postoperatively and were not significantly different, the visual analog scale scores for pain (1.9 ± 2.1 vs. 1.2 ± 1.7, P = .034) and American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) scores (83.1 ± 14.3 vs. 88.5 ± 12.2, P = .018) were significantly worse in the FCT group at 6 months postoperation. The retear rate was significantly higher in the FCT group (25.0 vs. 10.0%, P = .018). An FCT was a significant risk factor for retears (OR, 3.0; P = .015); however, a subgroup analysis revealed that the retear rate according to the management strategy for the folded portion (débridement of the folded portion vs. en masse repair including the folded portion) was not significantly different (26.7 vs. 24.0%, P > .99). CONCLUSION: The risk factors for FCTs were heel-type spur and delamination. The retear rate was significantly higher for patients with FCTs. An FCT was indicative of poor quality of the remaining tendon; therefore, FCT may be a prognostic factor for worse functional outcomes during the early postoperative period and poor healing potential.

Effects of comorbidities on the outcomes of manipulation under anesthesia for primary stiff shoulder.

BACKGROUND: Studies on the effects of manipulation under anesthesia (MUA) for primary stiff shoulder when different comorbidities are present are lacking. Our aim was to assess how comorbidities influence the recovery speed and clinical outcomes after MUA. METHODS: Between April 2013 and September 2018, 281 consecutive primary stiff shoulders in the frozen phase treated with MUA were included in this study. We investigated the comorbidities of patients and divided them into the control (n = 203), diabetes mellitus (DM) (n = 32), hyperlipidemia (n = 26), and thyroid disorder (n = 20) groups. The range of motion (ROM) and clinical scores for each group before MUA and 1 week, 6 weeks, and 3 months after MUA were comparatively analyzed. We identified the ROM recovery time after MUA and the responsiveness to MUA. Then, subjects were subdivided into early and late recovery groups based on their recovery time and into successful and nonsuccessful MUA groups based on their responsiveness to MUA. RESULTS: Significant improvements in ROM and clinical scores at 3 months after MUA were observed in all groups. Significant differences in ROM among the 4 groups were also observed during follow-up (P < .05). The DM group had significantly lower ROM values, even at 3 months after MUA, compared with the control group. The ROM recovery speed after MUA was slowest in the DM group, followed by the thyroid disorder, hyperlipidemia, and control groups. Most (90.6%) of the DM group experienced late recovery. The proportion of nonsuccessful MUA was higher in the DM and thyroid disorder groups than that in the control and hyperlipidemia groups (P = .004). During follow-up, there were no differences among groups regarding the visual analog scale, University of California at Los Angeles shoulder, and Constant scores. CONCLUSION: The ROM recovery speed and responsiveness to MUA for primary stiff shoulder were poorer for the DM and thyroid disorder groups than for the control group. In particular, compared with any other disease, outcomes were poorer when the comorbidity was DM. If patients have comorbidities, then they should be informed before MUA that the comorbidity could affect the outcomes of treatment.

Incidence and risk factors of acromial fracture following reverse total shoulder arthroplasty.

BACKGROUND: The occurrence and related predictors of acromial fracture following reverse total shoulder arthroplasty (RTSA) have not been fully elucidated. The aim of this study was to determine the incidence and risk factors of acromial fractures after RTSA. METHODS: We conducted a multicenter, retrospective case-control study of 787 cases (29 in acromial fracture group and 758 in control group) that underwent RTSA performed by 6 surgeons. The mean duration of follow-up after RTSA was 31.6 ± 21.8 months (range, 12-136 months). Demographic variables (age, sex, arm dominance, body mass index, working status, bone mineral density [BMD]), clinical variables (preoperative diagnosis, previous operation, implant design, preoperative clinical scores, screw size in glenoid fixation, postoperative rehabilitation), and radiographic variables (acromial thickness, critical shoulder angle, deltoid length, humeral offset to lateral acromion) were investigated. To determine risk correlation, univariate analysis and multivariate logistic regression analysis with calculated odds ratios (ORs) were performed. RESULTS: Postoperative acromial fractures occurred in 29 of the 787 shoulders with RTSA (3.7%). Acromial fractures were detected at a mean of 10.0 months (range, 1-66 months) postoperatively. Univariate analysis revealed that the occurrence of an acromial fracture was significantly associated with a previous operation (38% [11 of 29] vs. 21% [156 of 758], P = .025) and BMD (-2.33 vs. -1.74, P = .013). Multivariate logistic regression analysis found that the occurrence of a postoperative acromial fracture was significantly associated with a previous operation (P = .034; OR, 2.91; 95% confidence interval, 1.08-7.84) and deltoid length (P = .004; OR, 1.04; 95% confidence interval, 1.01-1.07). CONCLUSION: Acromial fracture following RTSA is not an uncommon complication, with an overall incidence of 3.7%. A previous operation, increased deltoid length, and low BMD were risk factors of acromial fracture following RTSA.

Optimal insertion site of glenoid baseplate in reverse total shoulder arthroplasty: anatomical simulation using three dimensional image processing software.

PURPOSE: Conventionally, the central structure of the baseplate is inserted through the point where the vertical and horizontal axes of the glenoid intersect (conventional insertion site (CIS)). However, there is scanty theoretical evidence that CIS has the optimal bone stock. We evaluated the optimal insertion site for the glenoid baseplate through the three-dimensional volumetric measurement of the glenoid bone stock. METHODS: Pre-operative computed tomography (CT) images of 30 consecutive reverse total shoulder arthroplasty procedures were analyzed. Three-dimensional image processing software was used to reconstruct CT and volumetrically measure the glenoid bone stock according to the simulated central peg. A simulated central peg was inserted to the medial pole of the scapula from 49 points determined along with the intersect point of the vertical and horizontal axes of the glenoid CIS at 2-mm intervals. The overlapped volume between the simulated central peg and glenoid vault, representing the amount of glenoid bone stock along the passage of the central peg, was then automatically calculated. RESULTS: The depth of the glenoid vault was 25.5 ± 3.0 mm (range, 19.3-31.5), and the mean overlapped volume between the simulated central peg and the glenoid vault was 623.0 ± 185.8 ml. The optimal insertion site for the bony purchase of the central peg was 2 mm inferior and posterior from the CIS (765.3 ± 157.5). CONCLUSION: The optimal insertion site of the baseplate is located slightly inferiorly and posteriorly to the CIS. This anatomical information may be used as a reference to determine the optimal insertion site of the baseplate according to an implant of a surgeon's choice.

Incidence of Cutibacterium acnes from shoulder arthroplasties in Asians: ethnic differences should be considered.

BACKGROUND: Most studies on Cutibacterium acnes in shoulder surgery have been conducted in the Western population, and studies on Asians are rare. We evaluated the incidence and risk factors of C acnes in shoulder arthroplasty in Asians. METHODS: We retrospectively analyzed 154 patients between January 2017 and May 2019 who underwent shoulder arthroplasty. Swabs were taken after skin preparation from the skin surface of the anterior acromion, axilla, and joint fluid to study the incidence of C acnes. Before skin preparation we also collected swabs from the anterior acromion, axilla, and thigh from 59 of the 154 patients. RESULTS: Eight of 154 patients after and 6 of 59 patients before skin preparation were positive for C acnes. C acnes were found in 2 patients at the anterior acromion and in 6 at the synovial joint after skin preparation and in 1 patient at the axilla, in 5 at the anterior acromion, and in 3 at the thigh before preparation. History of steroid injection and number of steroid injections were significantly associated with C acnes isolation (P = .039 and P = .006, respectively), whereas age, sex, body mass index, shoulder surgery history, hypertension, diabetes, and cerebrovascular disease were not, as were serum inflammatory markers, including white blood cell count, C-reactive protein level, and erythrocyte sedimentation rate. CONCLUSION: A total of 5.2% of the patients after skin preparation and 10.2% of patients before skin preparation were found to be positive for C acnes. The incidence of C acnes in patients who underwent shoulder arthroplasties in Asia was low and, thus, ethnic differences should be considered for C acnes. The history and number of steroid injections were associated with isolation of C acnes.

Neurologic deficit after reverse total shoulder arthroplasty: correlation with distalization.

BACKGROUND: Neurologic problems after reverse total shoulder arthroplasty (RTSA) have been reported, but there are a lack of studies regarding which nerve(s) are damaged and the outcomes for the patients who had neurologic complications after RTSA. The purpose of this study was to assess the prevalence and outcomes of neurologic deficit after RTSA and to evaluate the correlation between nonanatomic rearrangement of the shoulder joint and neurologic complications after RTSA. We hypothesized that the neurologic deficit was associated with excessive distalization or lateralization of the humerus after RTSA. METHODS: RTSA was performed on 182 consecutive shoulders with cuff tear arthropathy. Comparative analysis was performed on 34 shoulders with (group 1) and 148 shoulders without (group 2) neurologic deficit. RESULTS: The mean follow-up period in the study was 58.5 months (range: 24-124). The mean age was 71.5 ± 7.7 years in group 1 and 73.1 ± 7.2 years in group 2. Neurologic deficit after RTSA was found in 34 shoulders (19%). The mean postoperative acromiohumeral distance was 34.1 ± 11.0 mm in group 1 and 29.4 ± 7.6 mm in group 2 (P = .015). Significant differences in terms of postoperative distalization of the humerus were seen between group 1 (24.5 ± 9.4 mm) and group 2 (20.5 ± 8.3 mm) (P = .009). The most common forms of neurologic deficit after RTSA were axillary nerve (41.2%) and radial nerve (15%) injuries. Thirty shoulders (88%) had neuropraxia, and 4 shoulders (12%) had axonotmesis. By conservative treatment, all patients with neurologic complications achieved complete recovery without any additional surgery; the mean recovery period was 7.4 months (range: 2-38 months). CONCLUSION: Neurologic deficit occurred in 19% of patients who underwent RTSA, and it was significantly correlated with humeral distalization after surgery. Axillary nerve was mostly involved, and all patients with neurologic deficit achieved complete recovery without any additional surgery.