Radiographic Factors of Proximal Junctional Failure According to Age Groups in Adult Spinal Deformity.

Background: Patient age has been associated with the development of proximal junctional failure (PJF). The characteristics of adult spinal deformity (ASD) are considered different between younger and older age groups. We hypothesized that the radiographic risk factors of PJF would be different according to age groups. This study aimed to evaluate different radiographic risk factors of PJF between two age groups undergoing thoracolumbar fusion for ASD. Methods: ASD patients aged ≥ 60 years who underwent thoracolumbar fusion from the low thoracic level (T9-T12) to the sacrum were included. The minimum follow-up duration was 2 years. PJF was defined as proximal junctional angle (PJA) ≥ 20°, fixation failure, fracture, myelopathy, or necessity of revision surgery. Using various radiographic risk factors including age-adjusted ideal pelvic incidence (PI)-lumbar lordosis (LL), univariate and multivariate analyses were performed separately in two age groups: < 70 years and ≥ 70 years. Results: A total of 186 patients (90.3% women) with a mean age of 69 years were enrolled. The mean follow-up duration was 67.4 months. PJF developed in 97 patients (52.2%). There were fractures in 53 patients, PJA ≥ 20° in 26, fixation failure in 12, and myelopathy in 6. PJF developed more frequently in patients 70 years or older than in those younger than 70 years. In patients aged less than 70 years, preoperative LL, PI-LL, and a change in LL were significant risk factors in univariate analysis. Multivariate analysis showed only a change in LL was significant for PJF development (odds ratio [OR], 1.025; p = 0.021). On the other hand, in patients 70 years or older, postoperative LL, postoperative PI-LL, and overcorrection relative to the conventional PI-LL target (within ± 10°) and age-adjusted ideal PI-LL target were significant risk factors. On multivariate analysis, only overcorrection of PI-LL relative to the age-adjusted ideal target was a single significant risk factor of PJF (OR, 5.250; p = 0.024). Conclusions: In patients younger than 70 years, a greater change in LL was associated with PJF development regardless of PI-related values. However, in older patients, overcorrection of PI-LL relative to the age-adjusted PI-LL target was a significant risk factor of PJF.

Clinical Outcomes and Infection Rates Following Revision Total Knee Arthroplasty: Aseptic Failure versus Septic Failure.

Background: It is controversial whether revision total knee arthroplasty (TKA) due to septic failure shows inferior clinical outcomes compared with TKA due to aseptic failure. Moreover, few studies have compared the infection rates after revision TKA between aseptic and septic failure. We aimed to compare the clinical outcomes and infection rates after aseptic and septic revision TKA. Methods: Between April 2006 and May 2019, 68 and 26 patients underwent revision TKA due to aseptic failure (aseptic group) and septic failure (septic group), respectively. The postoperative range of motion (ROM), Western Ontario and McMaster Universities Osteoarthritis index, Knee Society Knee Score (KSKS), Knee Society Function Score (KSFS), and infection rates were compared between the two groups. Results: The mean follow-up durations in the aseptic and septic groups were 44.4 and 54.8 months, respectively. The septic group showed inferior postoperative ROM (124.1° and 109.4°, p = 0.004), KSKS (88.9 and 78.8, p = 0.001), and KSFS (72.8 and 59.0, p = 0.001). Three patients of aseptic group had infection. Three patients of septic group had recurred infection (same pathogen with the first infection) and 1 patient had a new infection (different pathogen). The septic group showed slightly higher but not significantly different infection rates (4.4% and 15.4%, p = 0.089). Conclusions: Revision TKA with septic failure showed inferior postoperative clinical outcomes compared with aseptic revision surgery. A slightly higher infection rate was observed in the septic group but it was not significantly different.

Does the Amount of Correction of Sagittal Deformity Really Promote Proximal Junctional Kyphosis? Multivariate Analyses According to Uppermost Instrumented Vertebra Levels.

BACKGROUND: The present study assumed that the effects of deformity correction amounts on proximal junctional kyphosis (PJK) development after long deformity surgery would vary according to uppermost instrumented vertebrae (UIV) levels. Our study was to reveal the association between the amount of correction and PJK according to UIV levels. METHODS: Adult spinal deformity patients aged >50 years who underwent thoracolumbar fusion (≥4 levels) were included. PJK was defined by proximal junctional angles ≥15°. Presumed demographic and radiographic risk factors for PJK were evaluated including parameters regarding the correction amount such as postoperative change in lumbar lordosis and postoperative offset grouping, the value associated with age-adjusted pelvic incidence-lumbar lordosis mismatch. The patients were divided according to UIV levels of T10 or above (group A) and T11 or below (group B). Multivariate analyses were performed separately for both groups. RESULTS: The present study included 241 patients (74 for group A and 167 for group B). PJK developed in approximately half of all patients within an average of 5 years of follow-up. For group A, only body mass index (P = 0.002) was associated with PJK. No radiographic parameters were correlated. For group B, postoperative change in lumbar lordosis (P = 0.009) and offset value (P = 0.030) were significant risk factors for PJK development. CONCLUSIONS: The correction amount of sagittal deformity increased the risk of PJK only in patients with UIV at or below T11. However, it was not associated with PJK development in patients with UIV at or above T10.

Substance P Inhibitor Promotes Tendon Healing in a Collagenase-Induced Rat Model of Tendinopathy.

BACKGROUND: The substance P-neurokinin 1 receptor pathway has been proposed as a therapeutic target for tendinopathy. However, there is a lack of evidence regarding its practical applications. PURPOSE: To investigate the therapeutic effects of substance P inhibitor (SPI) on inflamed tenocytes in vitro and in a collagenase-induced rat model of tendinopathy in vivo. STUDY DESIGN: Controlled laboratory study. METHODS: We analyzed the mRNA levels of inflammatory (cyclooxygenase [COX]-2 and interleukin [IL]-6) and tenogenic (Mohawk and scleraxis [SCX]) markers using reverse transcription quantitative polymerase chain reaction to demonstrate the effects of SPI on lipopolysaccharide-treated (inflamed) tenocytes. A collagenase-induced rat model of tendinopathy was created by injecting 20 µL of collagenase into the Achilles tendon. A behavior test using an incapacitance apparatus was performed to detect changes in postural equilibrium. The tendon specimens were obtained, and their gross findings were examined. The tensile strength was measured, and histopathological evaluation was performed (hematoxylin and eosin, alcian blue, and immunohistochemical staining). RESULTS: The mRNA levels of COX-2, IL-6, Mohawk, and SCX differed significantly between inflamed tenocytes and those treated with SPI. SPI improved the weight burden in a rat model of tendinopathy in a behavioral test. The specimens of the SPI group showed a normal tendon-like appearance. In the biomechanical test, the tensile strength of the SPI group was significantly greater than that of the tendinopathy group. In the histopathological evaluation, the degree of collagen matrix breakdown was mild in the SPI group. In alcian blue staining, only small focal depositions of proteoglycans and glycosaminoglycans were observed in the SPI group. The SPI group showed decreased expression of IL-6 and neurokinin 1 receptor. CONCLUSION: This study suggests that SPI has therapeutic effects on tendon healing and restoration in a collagenase-induced rat model of tendinopathy. CLINICAL RELEVANCE: SPI is a promising agent for tendinopathy in humans.

Clinical course in patients with chronic undifferentiated arthritis of the elbow after arthroscopic synovectomy.

BACKGROUND: Surgical treatment can be considered for patients with undifferentiated arthritis (UA) limited to the elbow joint. The purpose of this study was to analyze the clinical outcomes of arthroscopic synovectomy. METHODS: Nineteen patients who underwent arthroscopic synovectomy for chronic UA of the elbow between 2006 and 2019 were enrolled in this study. One patient was excluded because of evidence of tuberculosis in the biopsy. Chronic UA of the elbow was defined as (1) localized synovitis diagnosed by magnetic resonance imaging, (2) no specific cause, and (3) no response to conservative treatment for >3 months. We compared baseline characteristics and clinical outcomes between the remission and disease progression groups. RESULTS: Postoperatively, synovitis was controlled in 13 patients. In 5 patients, the symptoms disappeared after surgery without any medical treatment. Four patients discontinued disease-modifying antirheumatic drugs. Nine patients were classified as in remission. The disease progression group had a longer symptom duration, elevated rheumatoid markers, and higher Larsen grading. However, the difference was not statistically significant. CONCLUSIONS: Arthroscopic synovectomy achieved remission in approximately 47% of patients with chronic UA of the elbow. Although arthroscopic synovectomy did not prevent RA, it can be considered for rapid resolution of synovitis and diagnostic purposes.

Comparison of Survival Rate and Outcomes Between Conventional and Navigation-Assisted Primary Total Knee Arthroplasty in Severe Varus Knees: A Minimum 10-Year Follow-Up.

BACKGROUND: This study aimed to compare the long-term clinical and radiographic outcomes and survival rates between navigation-assisted (NAV) total knee arthroplasty (TKA) and conventional (CON) TKA in patients with preoperative severe varus deformity. METHODS: From January 2005 to December 2011, 152 TKAs and 62 TKAs with preoperative hip-knee-ankle (HKA) angles more than 15° were enrolled in the CON-TKA and NAV-TKA group with 135.7 months follow-up. Clinical outcomes (Western Ontario and McMaster University Osteoarthritis Index and Knee Society Scores), radiographic outcomes (HKA, α, ß, γ, and δ angles), and survivorship were compared between the groups. RESULTS: The mean value of radiographic outcomes was not statistically different; however, outliers of the HKA angle were significantly higher in the CON-TKA group (18.4% versus 8.1%, P = .04). However, long-term clinical outcomes were similar between both groups. The cumulative survival rate was 96.1% in the CON-TKA group and 96.8% in the NAV-TKA group, with no difference between the groups (P = .962). CONCLUSION: NAV-TKA showed fewer outliers in the HKA angle for severe preoperative varus deformity compared with CON-TKA. The long-term clinical outcomes and survival rates were similar between the 2 techniques. A survival rate of more than 96% was observed in both groups. STUDY DESIGN: Level III, retrospective comparative study.

Microinstability characterised by small and easily overlooked anterior labral or Hill-Sachs lesions can be managed with arthroscopic anterior labral repair.

PURPOSE: Some young individuals present with shoulder pain without a definite history or complaint of instability. However, careful history taking, physical examination, and high-quality magnetic resonance imaging may reveal evidence of instability of which the patient is unaware. Therefore, a clearer definition of these ambiguous patients is needed. This study aimed to report the characteristics and surgical outcomes of patients with microinstability compared to those of patients with classic recurrent anterior shoulder instability. METHODS: From 2005 to 2018, 35 patients with microinstability (group M) underwent arthroscopic anterior labral repair (AALR) and were compared to 35 sex- and age-matched patients with classic recurrent anterior shoulder instability (group C) who also underwent AALR. Baseline characteristics, preoperative apprehension test findings, preoperative imaging for the presence of anterior labral and Hill-Sachs lesions, preoperative and postoperative (over 2 years) range of motion (ROM) and functional scores, final complications, and patient satisfaction were analysed. RESULTS: The most common chief complaints in groups M and C were pain (29/35) and both pain and instability (27/35), respectively. Only pain during the apprehension test was predominant in group M (M vs. C, 27 vs. 1, p < 0.001). High incidence of chronic repetitive injuries (26/35) and acute trauma (28/35) were observed in groups M and C, respectively. Over half of the patients in group M showed anterior labral lesions on magnetic resonance arthrography (MRA, 18/35), and 21 patients had Hill-Sachs lesions on MRA/three-dimensional computed tomography. Finally, 29 patients showed either anterior labral or Hill-Sachs lesions on preoperative imaging. The lesion severity was higher in group C than that in group M. All patients underwent AALR with/without the remplissage procedure, with no significant differences in final clinical outcomes, complications, and patient satisfaction between the groups. CONCLUSIONS: Microinstability is diagnostically challenging and can be diagnosed in young patients with ambiguous shoulder pain during motion, without instability. Pain on anterior apprehension test and subtle labral and/or Hill-Sachs lesion on imaging study could be diagnostic clues. This condition can be managed with arthroscopic anterior labral repair with or without the remplissage procedure. The possibility of microinstability in young patients with shoulder pain should always be considered, and small anterior labral or Hill-Sachs lesions should be closely monitored. LEVEL OF EVIDENCE: III.

Artificial intelligence-based classification of bone tumors in the proximal femur on plain radiographs: System development and validation.

PURPOSE: Early detection and classification of bone tumors in the proximal femur is crucial for their successful treatment. This study aimed to develop an artificial intelligence (AI) model to classify bone tumors in the proximal femur on plain radiographs. METHODS: Standard anteroposterior hip radiographs were obtained from a single tertiary referral center. A total of 538 femoral images were set for the AI model training, including 94 with malignant, 120 with benign, and 324 without tumors. The image data were pre-processed to be optimized for training of the deep learning model. The state-of-the-art convolutional neural network (CNN) algorithms were applied to pre-processed images to perform three-label classification (benign, malignant, or no tumor) on each femur. The performance of the CNN model was verified using fivefold cross-validation and was compared against that of four human doctors. RESULTS: The area under the receiver operating characteristic (AUROC) of the best performing CNN model for the three-label classification was 0.953 (95% confidence interval, 0.926-0.980). The diagnostic accuracy of the model (0.853) was significantly higher than that of the four doctors (0.794) (P = 0.001) and also that of each doctor individually (0.811, 0.796, 0.757, and 0.814, respectively) (P<0.05). The mean sensitivity, specificity, precision, and F1 score of the CNN models were 0.822, 0.912, 0.829, and 0.822, respectively, whereas the mean values of four doctors were 0.751, 0.889, 0.762, and 0.797, respectively. CONCLUSIONS: The AI-based model demonstrated high performance in classifying the presence of bone tumors in the proximal femur on plain radiographs. Our findings suggest that AI-based technology can potentially reduce the misdiagnosis of doctors who are not specialists in musculoskeletal oncology.

Clinical and structural outcome of intra-articular steroid injection for early stiffness after arthroscopic rotator cuff repair.

PURPOSE: Direct comparative results of patients with early stiffness after arthroscopic rotator cuff repair (ARCR) with and without steroid injection are still unclear. This study aimed to evaluate the clinical and structural effect of intra-articular steroid injection for early stiffness after ARCR. METHODS: From 2011 and 2016, a total of 417 patients who underwent ARCR for less than medium-sized tears with 35.8 ± 22.6 months follow-up were retrospectively analyzed. Patients with shoulder stiffness [forward flexion (FF) < 120˚] or pain at 2 months after ARCR were performed intra-articular steroid injection, and four groups were established [+ stiffness/ + injection (SI, 158 patients), + stiffness/-injection (SNI, 92 patients), -stiffness/ + injection (NSI, 33 patients), and -stiffness/-injection (NSNI, 134 patients)]. Shoulder range-of-motion (ROM) and functional score changes for over two years were analyzed, and six month tendon integrity were evaluated using magnetic resonance imaging. RESULTS: Comparing SI and SNI group, ROM (except internal rotation) and functional score changes did not differ during the early period (2-6 and 2-12 months). However, comparing whether steroid injected (SI/NSI) or not (SNI/NSNI), the formers showed significantly higher improvement of both ROM and functional scores during the early and late period (2-24 months). A six month tendon integrity was not different across four groups and whether steroid injected or not. CONCLUSIONS: Intra-articular steroid injections do not appear to have a short-term clinical improving effect by comparing patients with stiff shoulders after ARCR with and without steroid injections. However, intra-articular steroid injection at two months after ARCR did not affect the tendon integrity at post-operative six months.

Outcomes of revision total hip arthroplasty using the modular dual mobility acetabular system to treat recurrent dislocation.

BACKGROUND: Recurrent dislocation is a difficult complication after total hip arthroplasty (THA). This study aimed to report the clinical and radiographic outcomes of revision THA using the modular dual mobility (MDM) acetabular system to treat recurrent dislocation. METHODS: Between March 2015 and February 2019, 34 revision THAs were performed using the MDM system for treating recurrent dislocation in a single institution. Of these, 32 revision THAs (32 patients) that satisfied a minimum follow-up of one year (mean, 4 years) were included in this study. Patient-reported outcomes, complication rates, and radiographic results were evaluated. RESULTS: Seventeen patients (53.1%) had lumbar degenerative kyphosis, and six (18.8%) had surgically fused lumbar spines during the index operation. All acetabular components were revised, whereas femoral stems were retained in 29 patients (90.6%). No redislocation or intraprosthetic dislocation was noted after revision. One additional revision was required for acetabular loosening with periprosthetic joint infection. No additional revision was performed for aseptic loosening. A partial radiolucent line was found in two hips (6.3%) confined to one acetabular zone. CONCLUSIONS: Revision THA using the MDM system was effective in treating recurrent dislocation in a group of patients with a high prevalence of lumbar spinal pathology. During a mean follow-up of 4 years, one additional revision THA was performed for septic loosening and none for aseptic loosening.

Combination of intramuscular transplantation of autologous mononuclear bone marrow cells with sympathectomy (L2, 3) in patients with peripheral arterial disease(PAD).

BACKGROUND: In most patients with severe, chronic extremity ischemic diseases, intervention or surgical treatment is often not suitable. Combination of intramuscular transplantation of autologous monocular bone marrow cells (AMBMCs) and sympathectomy (L2, 3) has been proved therapeutically beneficial. METHODS: We studied 170 patients (combined group 80, control group 90) with extremity ischemia (TAO, ASO FontaineⅡ,Ⅲ, Ⅳ) between January 2013 and September 2019. RESULTS: In contrast to pre-operation, the walking distance of patients increased significantly (from 61.34 ± 52.23 m to 156.0 ± 32.4 m, p < 0.01), and the ankle-brachial index (ABI) remarkably improved (from 0.28 ± 0.13 to 0.59 ± 0.23, p < 0.05). CONCLUSION: Combined therapy is feasible and effective for patients with peripheral arterial disease (PAD).

Knot-Tying versus Knotless Suture Anchors for Arthroscopic Bankart Repair: A Comparative Study.

PURPOSE: This study aimed to compare the results of using knotless and knot-tying suture anchors in arthroscopic Bankart repair. MATERIALS AND METHODS: The patients who underwent arthroscopic Bankart repair between 2011 and 2017 using knot-tying and knotless suture anchors were retrospectively reviewed. We collected demographic data, clinical scores (pain visual analogue scale), functional visual analogue scale, American Shoulder and Elbow Society scores, and Rowe score), and range of motion (ROM). Re-dislocation and subjective anterior apprehension test rates between the two techniques were also analyzed. RESULTS: Of the 154 patients who underwent arthroscopic Bankart repair, 115 patients (knot-tying group: n=61 and knotless group: n=54) were included in this study. Of the 115 patients, 102 were male and 13 were female. The mean patient age was 27 years (range: 17-60), and the mean follow-up period was 43 months (range: 24-99). There were no significant differences in the final clinical scores and ROM between the two groups. Re-dislocation was observed in 6 (9.8%) and 4 (7.3%) patients in the knot-tying and knotless groups, respectively. Apprehension was observed in 11 (18.0%) and 12 (22.2%) patients in the knot-tying and knotless groups, respectively. There were no significant differences between the two groups in regards to re-dislocation and anterior apprehension. CONCLUSION: Re-dislocation rates and clinical scores were similar with the use of knotless and knot-tying suture anchors in arthroscopic Bankart repair after a minimal 2 year follow-up.

Posterior repair of isolated type 2 superior labrum anterior-posterior lesion prevents external rotation deficiency: long-term outcome study.

PURPOSE: This study aimed to evaluate the outcomes of arthroscopic type 2 superior labrum anterior-posterior (SLAP) lesion repair in the general population and compare clinical outcomes according to patient age and repair site. METHODS: Between 2005 and 2018, patients who underwent arthroscopic repair for isolated type 2 SLAP lesions were retrospectively reviewed. Baseline characteristics, pre- and postoperative [1-year and > 2-year (final)] shoulder range-of-motion, and functional scores, comprising the pain visual analogue scale (PVAS), functional VAS, and American Shoulder and Elbow Surgeons (ASES) score, were evaluated. Return to overhead activities and subjective satisfaction were assessed at the final follow-up, and patients were divided by age [group YB (< 40 years] and group OB (≥ 40 years)] and repair site [group P (only posterior labrum repair) and group AP (anterior and posterior labrum repair)]. Overall patient outcomes were analysed and compared between groups. RESULTS: This study included 54 patients (45 men) with a mean age of 37.1 ± 8.3 years. The mean follow-up was 90.8 ± 51.3 months. Two patients experienced early failure, and one patient had a ruptured biceps tendon during the follow-up period. Final functional scores improved compared to their preoperative scores in all patients, except three (all p < 0.001). Fifty patients (98.0%) were satisfied, and 39 patients (76.5%) were able to perform overhead sports without restriction. In 25 patients who attended more than 7 years of follow-up (mean, 11.3 ± 2.7 years), 21 patients (84%) had an ASES score ≥ 80, and all patients had PVAS ≤ 2. There was no significant difference in clinical outcomes between groups YB and OB. The final median external rotation was significantly more restricted in group AP than in group P (40 [25-65] vs. 60 [50-70], p = 0.002). CONCLUSION: Arthroscopic type 2 SLAP repair induced good short- and long-term clinical outcomes, return to overhead activities, and subjective satisfaction in the general population, regardless of age, due to the careful evaluation of patient history, physical examination, and imaging studies. However, performing only posterior repair seems sufficient since anterior labral SLAP lesion repair can limit ER. Isolated type 2 SLAP lesion posterior repair only is, thus, recommended to reduce external rotation deficit risk and increase satisfaction, regardless of patient age. STUDY DESIGN: Case series. LEVEL OF EVIDENCE: Level IV.

Complications of reverse shoulder arthroplasty: a concise review.

Reverse shoulder arthroplasty is an ideal treatment for glenohumeral dysfunction due to cuff tear arthropathy. As the number of patients treated with reverse shoulder arthroplasty is increasing, the incidence of complications after this procedure also is increasing. The rate of complications in reverse shoulder arthroplasty was reported to be 15%-24%. Recently, the following complications have been reported in order of frequency: periprosthetic infection, dislocation, periprosthetic fracture, neurologic injury, scapular notching, acromion or scapular spine fracture, and aseptic loosening of prosthesis. However, the overall complication rate has varied across studies because of different prosthesis used, improvement of implant and surgical skills, and different definitions of complications. Some authors included complications that affect the clinical outcomes of the surgery, while others reported minor complications that do not affect the clinical outcomes such as minor reversible neurologic deficit or minimal scapular notching. This review article summarizes the processes related to diagnosis and treatment of complications after reverse shoulder arthroplasty with the aim of helping clinicians reduce complications and perform appropriate procedures if/when complications occur.