Complications and Reinterventions of Reverse Total Shoulder Arthroplasty in a Korean Population: 14-Year Experience in Reverse Shoulder Arthroplasty.

Background: There are few reports on the revision or reintervention of reverse total shoulder arthroplasty (RTSA) in South Korea. The purpose of this study was to evaluate the true incidence of complications and reintervention of RTSA and clinical and radiological outcomes based on our 14-year experience in RTSA in a Korean population. Methods: Between March 2008 and June 2022, 412 consecutive cases of RTSA were performed in 388 patients with an average age of 74.4 years at our institute. Excluding 23 patients lost to follow-up, 365 patients (373 shoulders including 8 bilateral cases) who underwent primary RTSA with more than 6 months of follow-up were enrolled in this study. We evaluated those who had complications or reintervention including revision RTSA for failed RTSA. Patient charts were reviewed, and clinical outcomes including clinical scores, complications, and reintervention and radiologic outcomes were evaluated at the last follow-up. Results: Among the 373 shoulders that underwent primary RTSA, complications were found in 50 patients (13.94%, 10 men and 40 women with a mean age of 75.9 ± 6.7 years [range, 51-87 years]). The causes of complications were as follows: 13 acromion, coracoid, or scapular spine fractures, 10 loosening (glenoid: 5, humeral stem: 5), 5 infections, 4 periprosthetic fractures, 2 instability, 2 neurologic complications, and 14 miscellaneous complications. Twenty patients (5.63%, 4 men and 16 women with a mean age of 74.2 ± 8.2 years [range, 51-87 years]) underwent reintervention. The interval to the first reintervention was 27.8 ± 23.1 months (range, 0.1-78 months). The causes of reintervention (20 cases) were 8 loosening (glenoid: 4, humeral stem: 4), 5 infections, 5 fractures, and 2 instability. Among them, 15 component revisions (4.02%) were performed. At the last follow-up, American Shoulder and Elbow Surgeons, University of California at Los Angeles, and Simple Shoulder Test scores were improved from 25.4, 12.4, and 1.6 preoperatively to 40.4, 16.2, and 3.2, respectively. Forward flexion (48° to 87°), abduction (52° to 79°), external rotation (18° to 22°), and internal rotation (buttock to L2) were improved. Conclusions: After primary RTSA in a Korean population, the complication, reintervention, and revision rates were 13.94%, 5.63%, and 4.02%, respectively. Careful evaluation of the complications and adequate treatments should be performed.

Comparisons between treatment of isolated posterosuperior paralabral cysts and simultaneous treatment of cysts combined with associated shoulder pathologies: arthroscopic treatment of posterosuperior paralabral cysts.

INTRODUCTION: The purpose of this study is to report the radiologic and clinical outcomes of arthroscopic intervention for isolated posterosuperior paralabral cysts and simultaneous treatment of cysts combined with associated shoulder pathologies. MATERIALS AND METHODS: From March 2008 through December 2016, 70 cases (48 males and 22 females) operated on for symptomatic posterosuperior paralabral cysts were included. Mean age was 45 (range 18-69). These patients were classified into two groups depending on if they had accompanying lesions: Group I (isolated group, 27 patients) and Group II (concomitant group, 43 patients). Arthroscopic cyst decompression with a labral repair or posterior capsulotomy for patients without labral tear were performed. All concomitant pathologies were also operated simultaneously. Follow-up MRI were performed at postoperative 6 months and clinical outcomes were evaluated during the follow-up. RESULTS: Arthroscopic all intra-articular cyst decompression and labral repair was performed on 67 patients. In three patients, posterior capsulotomy without labral repair was performed for cyst removal. For 43 patients with concomitant lesions, 31 rotator cuff repairs, three SLAP repairs along with biceps tenodesis, two distal clavicle resections due to A-C joint arthritis, one calcific deposit removal, four Bankart repairs, and two acromioplasties were performed. The follow-up MRI showed complete cyst resorption except for two patients. The mean VAS, ASES, UCLA, SST and CS scores significantly improved at the last follow-up. Although both groups showed significantly improved range of motion after the surgery, improvement of ROM in Group II lagged at early periods of the rehabilitation. CONCLUSIONS: Arthroscopic labral repair with all intra-articular cysts decompression or simple posterior capsulotomy were both effective treatment modalities. If paralabral cysts were associated with other shoulder lesions, simultaneous treatment of combined lesions could be performed for the improved clinical outcomes at final follow-up with expected lag in the early rehabilitation period. LEVEL OF EVIDENCE: Level III, Retrospective Comparative Trial, Treatment Study.

Clinical evaluation of usefulness and effectiveness of sitting type continuous passive motion machines in patients with total knee arthroplasty: a study protocol for a single-blinded randomized controlled trial.

BACKGROUND: Total knee arthroplasty (TKA) is an important management strategy for patients with knee osteoarthritis (OA) refractory to conservative management. Postoperative range of motion (ROM) exercise is important to recover patients' activities of daily living. Continuous passive motion (CPM) is a machine that provides passive ROM exercises of the knee joint in a pre-defined arc of motion. The short- and long-term effects of CPM exercise are controversial. We hypothesized that the inconsistent results of the CPM exercise are due to poor fitting of CPM machines and measurement errors. This study aims to present a protocol for investigating a new type of CPM machine that could be applied in a sitting position in comparison with the conventional type of CPM machine for patients with unilateral TKAs. METHODS: This study presents the protocol of a prospective, multicenter, single-blinded, three-armed randomized controlled trial (RCT). One hundred and twenty-six patients receiving unilateral TKAs will be recruited at the physical medicine and rehabilitation clinics of two urban tertiary medical hospitals. The patients were randomly divided into three groups with a 1:1:1 allocation. The intervention group will receive two weeks of post-operative rehabilitation using a new type of CPM machine. The control group will receive 2 weeks of post-operative rehabilitation using conventional CPM machines. The third group will receive post-operative rehabilitation with both types of CPM machines. The primary outcome will be the change in the passive ROM of the affected knee joint from baseline to 2 weeks after baseline assessment. The secondary outcomes will be pain and functional measurements, and will include patient-reported outcomes and performance tests surveyed at multiple time points up to 3 months after TKA. DISCUSSION: This is the first RCT to investigate the effect of a new type of CPM machine. The results of this RCT will determine whether the position of the patients during CPM exercise is important in post-operative rehabilitation protocols after TKAs and will provide evidence for the development of proper rehabilitation guidelines after TKAs. TRIAL REGISTRATION: Clinical Research Information Service of Republic of Korea, KCT0005520, Registered on 21 October 2020, https://cris.nih.go.kr/cris/search/detailSearch.do/21750.

Mid-term outcomes of bony increased offset-reverse total shoulder arthroplasty in the Asian population.

BACKGROUND: To evaluate clinical and radiological outcomes of bony increased offset-reverse total shoulder arthroplasty (BIO-RSA) in the Asian population at mid-term follow-up. METHODS: From June 2012 to August 2017 at a single center, 43 patients underwent BIO-RSA, and 38 patients with minimum 2 years follow-up were enrolled. We evaluated the clinical and radiological outcomes, and complications at the last follow-up. In addition, we divided these patients into notching and no-notching groups and compared the demographics, preoperative, and postoperative characteristics of patients. RESULTS: Visual analogue scale, American Shoulder and Elbow Surgeons, University of California-Los Angeles Shoulder Scale, and Simple Shoulder Test scores improved significantly from preoperative (5.00, 3.93, 1.72, 3.94) to postoperative (1.72, 78.91, 28.34, 7.66) (p<0.05) outcomes. All range of motion except internal rotation improved significantly at the final follow-up (p<0.05), and the bone graft was well-incorporated with the native glenoid in all patients (100%). However, scapular notching was observed in 20 of 38 patients (53%). In the comparison between notching and no-notching groups (18 vs. 20 patients), there were no significant differences in demographics, radiological parameters, and clinical outcomes except acromion-greater tuberosity (AT) distance (p=0.003). Intraoperative complications included three metaphyseal fractures and one inferior screw malposition. Postoperative complications included ectopic ossification, scapular neck stress fracture, humeral stem relaxation, and late infection in one case each. CONCLUSIONS: BIO-RSA showed improved clinical outcomes at mid-term follow-up in Asian population. However, we observed higher scapular notching compared to the previous studies. In addition, adequate glenoid lateralization with appropriate humeral lengthening (AT distance) might reduce scapular notching.

Suture anchor fixation of comminuted inferior pole patella fracture-novel technique: suture bridge anchor fixation technique.

PURPOSE: Comminuted inferior pole fractures of the patella are notorious fractures where it is difficult to obtain rigid internal fixation by conventional tension band wiring. The purpose of this study is to evaluate the clinical and radiological outcomes of the suture bridge anchor fixation for these comminuted inferior pole fractures of the patella. METHODS: From March 2012 to December 2018, suture bridge anchor fixation for the inferior pole comminuted fracture of the patella was performed in 22 patients. There were 21 patients of inferior pole comminuted fracture and 1 patient of lower periosteal sleeve avulsion fracture. Clinical outcomes including SF-36 score, Knee injury and osteoarthritis outcome score (KOOS) and post-operative range of motion were evaluated. In all patients, suture bridge anchor fixation was performed and, tension band wiring with K wire was added for large fragment fixation in two patients. We evaluated bony union, the patellar height using Insall-Salvati ratio and its complications. RESULTS: Mean age was 46 ± 20 (15-82) years. Mean follow-up period was 25 ± 18 (11-74) months. In all patients, bony union was achieved at postoperative 4 months. At final follow-up, mean SF-36 score was 72 ± 15 (30-91) points and KOOS score was 66.7 ± 16 (43-97). The average range of motion was 134 ± 5 (125-140) degrees. As a complication, one patient developed a wound infection and subsequent osteomyelitis of inferior pole fracture fragment. Compared to the normal knee, the Insall-Salvati ratio of the injured knee averages 0.73 and this smaller ratio less than 0.8 meant patella baja. CONCLUSIONS: In the comminuted inferior pole fractures of the patella, suture bridge anchor fixation showed good bony union and satisfactory clinical outcomes at the short-term follow-up and could be a satisfactory alternative treatment option. Even though suture bridge anchor fixation in these fractures caused decreased Insall-Salvati ratio (patella height), any patellofemoral pain and limited range of motion was not developed. LEVEL OF EVIDENCE: Level IV.

Risk factors for adjacent segment degeneration after iliac screw fixation in lumbar degenerative kyphoscoliosis.

PURPOSE: To analyze pre- and postoperative spinopelvic parameters and sagittal profiles in lumbar degenerative kyphoscoliosis (LDK) patients who underwent surgery using iliac screw (IS) and the incidence and risk factor of radiological adjacent segment degeneration (ASD). METHODS: A total of 32 patients, who had undergone surgical correction and lumbar/thoracolumbar fusion with pedicle screws and IS instrumentation for LDK with a minimum 2-year follow-up, were included. Ten cases with ASD (group 1) and 22 cases without ASD (group 2) were compared to see pre- and postoperative change in sagittal view of spine and adjacent segment. Parameters of both groups were analyzed before and after surgery with each parameters being tested on correlativity. All deformity types of patients were classified using Scoliosis Research Society (SRS)-Schwab classification. Risk factors of ASD were evaluated using variables of SRS-Schwab classification. RESULTS: Group 1, rather than group 2, showed significant increment in pelvic incidence (PI). Curve types, classified using SRS-Schwab classification, were all corrected using IS; and after correction, coronal curve type was N curve and PI minus lumbar lordosis (LL) and pelvic tilt showed tendency to decrease. Cases with preoperative sagittal vertical axis (SVA) more than 10 cm and with postoperative PI minus LL more than 20° were at higher risk of developing ASD. CONCLUSION: For those with high PI, it might be a risk to cause ASD. Maintaining normal thoracic and lumbar angle, correction of SVA less than 4 cm, and PI minus LL below 20° are proper ways to avoid ASD after surgery.

Fractalkine receptor chemokine (CX3CR1) influences on cervical and lumbar disc herniation.

BACKGROUND: Herniation of nuclear or disc material along with, inflammatory chemokines such as prostaglandin E2, interleukin-6, matrix metalloproteinase and nitric oxide has definite correlation, possibly they are over produced. CX3CL1 and its receptor (CX3CR1) are part of chemokine system involved in leukocyte recruitment and adhesion in chronic inflammatory disease, but its role in spinal herniated nucleus pulposus (HNP) is unknown. We evaluated the expression of CX3CL1 and CX3CR1 in patients with disc herniation to clarify the role of CX3CL1 and CX3CR1 in the disc degeneration and to compare between cervical and lumbar HNP. MATERIALS AND METHODS: The mRNA concentrations of CX3CL1/CX3CR1 chemokine were analyzed in the surgically obtained disc specimens from C-HNP (n = 13) and L-HNP (n = 13) by real-time polymerase chain reaction (PCR). The localization of CX3CL1/CX3CR1 chemokine in the disc of C-HNP and L-HNP patients was determined using immunohistochemical study. Blood samples from patients with C-HNP and L-HNP patients were stained for CX3CR1 with flow cytometric analysis. RESULTS: The CX3CL1 positive cell ratio in the discs was observed in both groups by immunohistochemical study. CX3CR1 was strongly expressed on endothelial cells in C-spine disc, but sparely expressed in L-spine disc. There was greater CX3CR1 mRNA expression in C-HNP patients than in L-HNP patients as quantified by reversal transcription-PCR (P = 0.010). CX3CR1 positive cell frequencies and CX3CR1 expression levels were increased in CD4 (+) T-cells and natural killer (NK) cells from patients with C-HNP (P = 0.210 and P = 0.040). CONCLUSIONS: This study identified that increases in CX3CL1 and CX3CR1-expressing cells are significantly related to pathomechanism of HNP for the first time. Especially, CD4 (+) T-cells and NK cells expressing CX3CR1 may play an important role in developing C-HNP.

Hypertrophy of the ligament flavum in degenerative lumbar stenosis associated with the increased expression of fractalkine (CX3CL1)/CX3CR1 chemokine.

Fractalkine (CX3CL1) and its receptor (CX3CR1) comprise a chemokine system involved in leukocyte recruitment and adhesion in chronic inflammatory disease, but its role in spinal diseases is unknown. The purpose of this study is to investigate the role of CX3CL1/CX3CR1 chemokine on hypertrophy of the ligamentum flavum (LF) in degenerative lumbar stenosis (DLS) compared with that of non-degenerative spinal condition (NDS) of the lumbar spine and correlation between expression of CX3CL1/CX3CR1 chemokine and thickness of LF. The mRNA concentrations of CX3CL1/CX3CR1 chemokine were analyzed in the surgically obtained LF specimens from DLS (n = 10) and NDS (n = 11) by real-time PCR. The localization of CX3CL1/CX3CR1 chemokine within the LF was determined using immunohistochemical study. Plasma levels of soluble FKN (sFKN) were measured by enzyme-linked immunosorbent assay, respectively. The thickness of the LF was measured with axial T1-weighted MRI. The cells that express CX3CL1/CX3CR1 chemokine ratio in the LF observed in DLS group were substantially higher than in NDS group. In ELISA, the plasma levels of sFKN was significantly increased in DLS compared with patients in the other groups (p = 0.006). There was greater CX3CL1/CX3CR1 expression in DLS as quantified by RT-PCR (p = 0.004, 0.010). Thickness of LF in patients was significantly correlated with serum CX3CL1 level (R(2) = 0.824, p = 0.003) and with mRNA expression of CX3CL1/CX3CR1 (R(2) = 0.671, p = 0.000) (R(2) = 0.514, p = 0.001). This study identified for the first time that increases in CX3CL1 and CX3CR1-expressing cells are significantly related to LF hypertrophy.