Acquired Acromion Compromise, Including Thinning and Fragmentation, Is Not Associated With Poor Outcomes After Reverse Shoulder Arthroplasty.

BACKGROUND: Acquired acromial compromise, including thinning (less than 30% of the normal acromion) or fragmentation resulting from acromiohumeral impingement or previous acromioplasty, is a concern in reverse shoulder arthroplasty (RSA). This condition may lead to shoulder pain and difficulties in arm elevation because of acromial insufficiency fracture. QUESTIONS/PURPOSES: (1) Do patients with acromial compromise (thinning less than 30% of normal acromion or fragmentation) have worse functional outcome scores, ROM, and strength after RSA compared with patients without acromial compromise? (2) Are patients with acromial compromise at a higher risk of complications such as acromial insufficiency fracture after RSA? (3) Do patients who develop acromial insufficiency fracture have predisposing associated factors and worse clinical outcomes? METHODS: Between January 1, 2016, and December 31, 2020, we treated 398 patients with RSA, and all patients were considered potentially eligible for this study. Our clinic is part of the orthopaedic department within a tertiary general hospital, serving patients from across the country. Among them, 49% (197 of 398) of patients were excluded for the following reasons: 8% (31 of 398) because of proximal humerus fracture, 5% (19 of 398) because of osteonecrosis, 9% (35 of 398) because of previous infective arthritis, 5% (18 of 398) because of a deformed shoulder, 4% (14 of 398) because of poor general condition after surgery, 3% (12 of 398) because of death, and another 17% (68 of 398) were lost before the minimum study follow-up, leaving 51% (201 of 398) for analysis. A preoperative acromial compromise was defined as follows: (1) thinning of the acromion (< 3 mm), which means a thickness of less than 30% of the normal acromion thickness (8 to 9 mm), and (2) acromial fragmentation. Acromial thickness was measured using a CT scan. The middle portion of the anterolateral acromion, situated lateral to the distal end of the clavicle, was crosschecked using the axial view. Measurements were subsequently performed from both coronal and sagittal views. In all, 29 patients with acromion compromise and 172 without acromion compromise met the inclusion and exclusion criteria. There was no differential loss to follow-up before 2 years between patients with and without acromial compromise in this study (36% [16 of 45] versus 23% [52 of 224]; p = 0.12). We matched patients using propensity score, pairing them in a 1:3 ratio based on gender, age, bone mineral density, diagnosis, previous rotator cuff repair surgery, subscapularis repair or latissimus dorsi transfer performed during surgery, the type of prosthesis used, and follow-up duration. Twenty-three patients with acromial compromise (acromion compromised group) and 69 patients without acromial compromise (normal control group) were matched; the mean ± SD duration of follow-up was 40 ± 22 months in those with acromial compromise and 43 ± 19 months the in normal control group. Pre- and postoperative functional outcome scores, ROM, and shoulder strength were compared. Shoulder scaption refers to lifting the arm in the scapular plane, and scaption strength was measured by applying upward force with the arm at 90° while seated, pushing it as far as possible and measured using a handheld myometer. Complications, including acromial insufficiency fracture, scapular notching, dislocation, periprosthetic infection, and overall risk of complication, were analyzed. Acromial insufficiency fracture was diagnosed based on clinical and radiological findings. Clinically, sudden pain and tenderness at the acromion along with reduced shoulder elevation raised acromial insufficiency fracture suspicion. Radiologically, acromion tilt on plain radiograph or fracture line on coronal CT view confirmed diagnosis of acromial insufficiency fracture. RESULTS: Comparing both groups, patients with a compromised acromion had no difference in American Shoulder and Elbow Surgeons scores (60 ± 12 versus 64 ± 12; mean difference -4 [95% CI -11 to 2]; p = 0.16), Constant scores (48 ± 10 versus 54 ± 12; mean difference -6 [95% CI -13 to 0]; p = 0.06), forward flexion degree (125 ± 24 versus 130 ± 21; mean difference -5 [95% CI -16 to 6]; p = 0.36), and scaption strength (5 ± 3 versus 6 ± 3; mean difference -1 [95% CI -3 to 0]; p = 0.13). Having acromial compromise was not associated with increased risk of overall complications (30% [7 of 23] versus 19% [13 of 69], relative risk 2 [95% CI 1 to 4]; p = 0.26). However, the only complication that was higher in the acromial compromised group was infection (13% [3 of 23] versus 0% [0 of 69], relative risk not available; p = 0.01). Only the lateralized glenoid prosthesis demonstrated negative association with the acromial insufficiency fracture occurrence; no other factors showed an association. The use of lateralized glenoid prostheses was not observed in patients with acromial insufficiency fracture (0% [0 of 7] acromial insufficiency fracture versus 39% [33 of 85] no acromial insufficiency fracture, relative risk 0 [95% CI 0]; p = 0.047). CONCLUSION: In patients with acquired acromial compromise-such as thinning or fragmented acromion because of advanced cuff tear arthropathy or previous acromioplasty-primary RSA resulted in no different functional outcome score, ROM, shoulder strength, and overall complications compared with patients without acromial compromise. Our findings suggest that a thin or fragmented acromion may not necessarily be exclusion criteria for RSA, potentially aiding surgeons in their decision-making process when treating these patients. However, one of the major complications, postoperative infection, is more frequently observed in patients with acquired acromial compromise. Pre- and postoperative caution would be necessary to prevent and detect infection even when short-term outcomes are favorable in this study. Further studies with large cohorts and long-term follow-up durations are needed. LEVEL OF EVIDENCE: Level III, therapeutic study.

Atelocollagen Injection During Arthroscopic Rotator Cuff Repair for Small- to Medium-Sized Subacute or Chronic Rotator Cuff Tears Enhances Radiographic Tendon Integrity: A Propensity Score-Matched Comparative Study.

PURPOSE: To evaluate the clinical and structural outcomes of using injectable atelocollagen during arthroscopic rotator cuff repair (ARCR) for small- to medium-sized rotator cuff tears. METHODS: This retrospective study reviewed patients with small- to medium-sized full-thickness tears who underwent ARCR from 2016 to 2022 with a minimum 1-year follow-up. Propensity score (PS) matching was used to reduce bias. Tendon integrity was evaluated using magnetic resonance imaging (MRI) at postoperative 6 months. Clinical and structural outcomes were compared between the 2 groups. RESULTS: After PS matching, this study included 181 pairs of patients comparing ARCR with atelocollagen injection and without atelocollagen injection. Range of motion, muscle strength, and functional outcomes were significantly improved in both the atelocollagen group and the control group. Forward elevation and external rotation were significantly worse in the atelocollagen group compared with the control group at 2, 6, and 12 months postoperatively and at the final follow-up. In total, 125 patients (69.1%) in the atelocollagen group and 130 patients (71.8%) in the control group exceeded the minimal clinically important difference in the American Shoulder and Elbow Surgeons score without a significant difference between the 2 groups (P = .509). The mean value of Sugaya grade on postoperative MRI evaluation was 2.03 ± 0.81 for the atelocollagen group and 2.24 ± 0.97 for the control group, with a significant difference between the 2 groups (P = .027). Tendon healing failure was observed in 12 patients (6.6%) in the atelocollagen group and 19 patients (10.5%) in the control group, with no statistical difference between the 2 groups (P = .189). CONCLUSIONS: Atelocollagen injection during ARCR for small- to medium-sized subacute or chronic rotator cuff tears did not show a benefit in clinical outcomes. However, postoperative MRI showed significantly lower Sugaya grade compared with the control group, with no significant difference in retear rate. LEVEL OF EVIDENCE: Level III, retrospective case-control study.

Knotless Bioabsorbable Anchors Placed on the Glenoid Face for Arthroscopic Bankart Repair.

BACKGROUND: Quantitative analysis of the glenoid face knotless-type anchor placement for arthroscopic Bankart repair has not been reported. PURPOSE: To evaluate the clinical and radiologic outcomes after arthroscopic Bankart repair using knotless bioabsorbable anchors depending on the anchor location. STUDY DESIGN: Case series, Level of evidence, 4. METHODS: A total of 124 patients (113 men and 11 women; age, 25.6 ± 7.5 years; follow-up time, 46.5 ± 18.2 months [range, 6.2-75.5 months]) who underwent arthroscopic Bankart repair with the bioabsorbable knotless anchor between 2017 and 2021 were included in this study. Among them, 118 patients were observed for >2 years (mean, 48.2 ± 16.8 months [range, 24-75.5 months]) and were analyzed for final clinical and radiologic outcomes. Using postoperative 6-month magnetic resonance imaging, remnant glenoid (%) and labral height were measured. Shoulder range of motion (ROM), radiographic osteoarthritic change, dislocation, apprehension test, and return to sports were recorded. Three groups were established based on the remnant glenoid, which represented the percentage of the exposed glenoid anteroposterior diameter to the original diameter using the best-fit circle method-group A: lower quartile; group B: interquartile; and group C: upper quartile-and variables were analyzed. RESULTS: Overall, the remnant glenoid was 57% ± 6.4% (range, 41.5%-75%) after the surgery. Osteoarthritic change, dislocations, and positive apprehension tests were observed in 5 (4.2%), 4 (3.4%), and 12 (10.2%) patients, respectively. A total of 34 (28.8%) and 64 (54.2%) patients could return to sports without and with restrictions, respectively. Comparing groups A, B, and C, postoperative labral height (7 ± 1, 7 ± 2, and 7 ± 1 mm; P = .623), final osteoarthritic change (1, 4, and 0; P = .440), positive apprehension tests (5, 5, and 2; P = .387), and return to sports (complete/restricted/unable, 6/18/5, 19/29/11, 9/17/4; P = .769) were not different. All ROM were similar across the groups (all P > .054), except for external rotation (ER) at postoperative 6 months (41.3°± 12.8°; 50.2°± 18.5°; and 49.8°± 15.2°; P = .050). However, ER after 1 year was similar across the groups (all P > .544). In further analysis, patients with positive apprehension tests had lower labral height compared with others (5 [4-6] mm and 7 [6-8] mm; P < .001). CONCLUSION: In arthroscopic Bankart repair, the placement of knotless bioabsorbable anchors on the glenoid face, combined with the remplissage procedure or rotator interval closure, resulted in a low recurrence rate and moderate return to sports. However, most patients had some restrictions in returning to sports. Moreover, this technique was not associated with postoperative arthritis and shoulder stiffness, including ER deficit, which was not affected by the position of the anchor on the glenoid face for a minimum 2-year follow-up.

Long-term Effectiveness and Outcome-Determining Factors of Arthroscopic Bankart Repair for Recreational Sports Population: An Assessment of 100 Patients With a Mean Follow-up of 12.7 Years.

BACKGROUND: A limited number of studies have reported the long-term effectiveness of and associated factors for recurrence of anterior shoulder instability after arthroscopic Bankart repair (ABR). PURPOSE: To report the long-term clinical outcomes after ABR in a recreational sports population and identify the associated factors that influence the final instability status. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A retrospective study was performed in patients treated with ABR between 2007 and 2013 by a single surgeon. Patient data, magnetic resonance imaging measurements of bone loss and glenoid track, and intra- and perioperative factors were analyzed. After a minimum follow-up of 10 years, patient-reported outcomes including the Western Ontario Shoulder Instability Index score, the Rowe score, the visual analog scale for pain and function, the American Shoulder and Elbow Surgeons score, and sports activity were assessed. The current instability status was classified into 3 groups: stable, apprehensive, and redislocated. These groups were statistically compared with respect to outcomes and associated factors. RESULTS: A total of 100 patients with a mean age of 22.4 ± 5.5 years and a mean follow-up of 12.7 ± 2.1 years were included. At the final follow-up, 38 patients (38%) showed recurrent symptoms: 19 patients (19%) with subjective apprehension and 19 patients (19%) with redislocation, including 10 patients (10%) with revision surgery. At the final follow-up, the redislocated group showed the lowest patient-reported outcomes and return to sports (both P < .001). The apprehensive group also showed a lower Western Ontario Shoulder Instability Index score (P = .011), Rowe score (P = .003), American Shoulder and Elbow Surgeons score (P = .027), and return to sports (P = .005) than the stable group. Participation in contact sports (P = .026), glenoid bone loss (P = .005), size of Hill-Sachs lesion (P = .009), and off-track lesions (P = .016) were all associated with recurrent symptoms, whereas age <20 years (P = .012), participation in contact sports (P = .003), and off-track lesions (P = .042) were associated with redislocation. CONCLUSION: After long-term follow-up in a recreational sports population, ABR demonstrated a 19% rate of subjective apprehension and 19% rate of redislocation, with a gradual decline in clinical outcomes and sports activity over time. Therefore, candidates for ABR should be selected based on consideration of risk factors such as off-track lesions, age <20 years, and participation in contact sports.

SPECT/CT for Early Detection of Stress Reactions After Reverse Shoulder Arthroplasty: Potential Clinical Significance.

ABSTRACT: The altered biomechanics after reverse shoulder arthroplasty, combined with the accumulation of various stress risers, can lead to stress fractures (SFs) around the prosthesis. The incidence of stress reactions (SRs) after reverse shoulder arthroplasty, characterized by pain and tenderness without radiographic or CT evidence of fractures, is approximately 4.2%, which is comparable to the incidence of SF (6.4%). Among patients with SR, a substantial 32% eventually progress to fractures during clinical follow-up. SPECT/CT is a promising tool that combines morphologic and metabolic information for assessing mechanical bone stress. Therefore, early detection of SR through SPECT/CT can help prevent SF.

Clinical and Structural Outcomes of Arthroscopic Rotator Cuff Repair in Patients Over 75 Years Are Comparable to Those in Younger Patients: A Propensity Score-Matched Comparative Study.

PURPOSE: To compare clinical and structural outcomes of arthroscopic rotator cuff repair (ARCR) in patients over 75 years and those under 75 years and to analyze the factors associated with retear and clinical outcomes after ARCR. METHODS: This retrospective study reviewed patients who underwent ARCR between 2011 and 2021 with at least 2 years of follow-up. Using propensity score matching for sex, tear size, subscapularis involvement, and follow-up time, this study included 54 patients older than 75 years (group A) and 54 patients younger than 75 years (group B). Cuff integrity was evaluated using magnetic resonance imaging (MRI). Structural and clinical outcomes were compared between the 2 groups. RESULTS: The mean improvements in external rotation (P = .030) and the American Shoulder and Elbow Surgeons (ASES) score (P = .043) were significantly higher in group A. Visual analog scales for pain and function, ASES score, and Constant score were significantly improved in both groups (all P = .001). On routine postoperative MRI at 6 months, the retear rate was 20.4% (11/54) in group A and 18.5% (10/54) in group B with no statistical difference between the 2 groups (P = .808). Factor analysis in group A showed that follow-up duration (P = .019), tear size in mediolateral dimension (P = .037), occupation ratio (P = .036), and incomplete repair (P = .034) were associated with retear, and mild glenohumeral arthritis (P = .003) and subscapularis involvement (P = .018) were associated with inferior Constant score. CONCLUSIONS: Clinical and structural outcomes after ARCR in patients aged 75 years or older are comparable to those in patients younger than 75 years. LEVEL OF EVIDENCE: Level III, retrospective case-control study.

Return to Sports Activity After Reverse Total Shoulder Arthroplasty.

Background: There are little published data on return to sports (RTS) after reverse total shoulder arthroplasty (RTSA). Purpose: To (1) determine the rate and timing of RTS after RTSA in an Asian population, (2) analyze predictive factors for RTS, and (3) determine the relationship between RTS after RTSA and clinical/radiological outcomes. Study Design: Case-control study; Level of evidence, 3. Methods: A retrospective review was performed on consecutive patients with diagnosis of irreparable rotator cuff tear (RCT), cuff tear arthropathy (CTA), or degenerative osteoarthritis who underwent RTSA between May 2017 and May 2020. Included were patients who played sports preoperatively in ≤3 years and had ≥2-year follow-up. Patients were divided into 2 groups based on responses to a telephone survey about RTS after RTSA: those who returned to sports (group A) and those who did not (group B). Patient characteristics, pre- and postoperative clinical features and functional scores, and radiologic outcomes (acromial fracture, scapular notching, heterotopic ossification, and loosening of humeral and glenoid component) were compared between the groups. Results: Of 59 eligible patients, 44 patients (28 in group A, 16 in group B) were included. The RTS rate after RTSA was 63.6%, and the mean RTS time was 9.1 months (range, 3-36 months). There was a significant group difference in body mass index (BMI) (group A, 24.3 ± 2.1; group B, 27.1 ± 4.4; P = .01) and preoperative diagnosis (CTA/irreparable RCT/degenerative osteoarthritis diagnoses: group A, 13/12/3; group B, 3/6/7; P = .03). Patients in group A showed significantly higher forward flexion (P = .03) and higher Simple Shoulder Test score (P = .02) than group B at final clinical follow-up. No significant difference in radiological outcomes was found between the groups. Conclusion: Patients with a low BMI and those diagnosed with CTA or irreparable RCT were found to have better RTS rates after undergoing RTSA, and forward flexion and Simple Shoulder Test scores at final follow-up were significantly higher in the RTS group, with no significant differences in complications.

Arthroscopic Repair of Large Subscapularis Tear Over the First Facet.

BACKGROUND: Long-term studies on arthroscopic repair of large subscapularis (SSC) tears over the first facet with or without supraspinatus (SSP) tear are limited. PURPOSE: To assess the structural and clinical outcomes of arthroscopic repair of large SSC tears using magnetic resonance imaging (MRI) and identify the factors related to SSC retear and poor outcomes. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: This study involved 109 patients (84.0 ± 36.2 months of follow-up) who underwent arthroscopic repair of large SSC tears (Yoo and Rhee classification type III [n = 81] or IV [n = 28]) between 2011 and 2019. All patients underwent MRI at 6.1 ± 0.4 months after surgery, and 79 of 109 patients (72.5%) were followed up over 7 years. Clinical outcomes (active range of motion, functional scores, and belly press strength) and final poor clinical outcomes (reoperation, osteoarthritic change, and poor clinical outcome) were recorded. SSP tear size, rotator cuff atrophy and fatty infiltration (Goutallier classification), SSC tendon integrity (intact, intermediate, definite tear), and SSP tendon integrity (Sugaya classification) were evaluated by MRI. RESULTS: The overall SSC retear rate was 8.3% (9/109) (type III, 2/81 [2.5%]; type IV, 7/28 [25.0%]; P < .001). SSC Goutallier grade 4 showed a higher retear rate than grade 3 (7/33 [21.2%] vs 2/33 [6.1%]; P = .149). A large SSP tear (in millimeters) (odds ratio [OR], 1.5; P = .003), SSC Goutallier grade 4 (OR, 10.8; P = .047), and SSP Goutallier grade 3 or 4 (OR, 0.02; P = .013) were independent factors for SSC retear. Clinical outcomes, except for external rotation, were poorer in patients with SSC retear than in those without retear. Final poor clinical outcomes were observed in 27 of 79 patients (34.2%); female sex (OR, 7.7; P = .007), SSC retear (OR, 8.2; P = .025), and SSP retear (OR, 4.7; P = .031) were independent factors. CONCLUSION: Arthroscopic repair of large SSC tears has shown promising structural outcomes for type III tears but not type IV tears. SSC retear was affected by SSC atrophy, as well as SSP tear size and atrophy. Approximately one-third of the final poor clinical outcomes could be predicted, and SSC retear, SSP retear, and female sex were associated with long-term poor clinical outcomes, underscoring the importance of carefully selecting patients for arthroscopic repair of large SSC tears.

Diagnostic Performance of Belly-Press Angle in Predicting the Severity of Subscapularis Tear.

BACKGROUND: Neglected partial subscapularis tears often cause functional impairment even after repair of the supraspinatus and infraspinatus tear is done. Numerous physical examinations for detecting partial subscapularis tears have been described in previous studies. PURPOSE: To analyze the relationship between the preoperative clinical features and the severity of a partial subscapularis tear and to provide diagnostic clues for patients requiring subscapularis repair. STUDY DESIGN: Cohort study (Diagnosis); Level of evidence, 2. METHODS: This retrospective study included 286 patients who underwent arthroscopic shoulder surgery between 2020 and 2022. Preoperative clinical features, including range of motion, functional scores, muscle strength ratio, modified belly-press test (measuring belly-press angle), and bear-hug test, were collected. Magnetic resonance imaging (MRI) evaluation was done according to the Yoo and Rhee classification. Types of subscapularis tear, supraspinatus lesion, and biceps lesion were recorded during arthroscopic surgery. A comparison of preoperative clinical features between the no-repair group (type 2A or less) and surgical repair group (type 2B or more) was done. The optimal cutoff value of the belly-press angle was determined and the diagnostic performance of the belly-press angle, bear-hug test, and MRI were evaluated using the receiver operating characteristic curve. RESULTS: Among 286 patients, 189 (66.1%) had subscapularis tears with type 2A or more. There was a significant difference in muscle strength ratio of the belly-press (P < .001), belly-press angle (P < .001), and bear-hug test (P < .001) between the no-repair group (type 2A or less) and the surgical repair group (type 2B or more). With a belly-press angle of 15° as a new cutoff value, the modified belly-press test showed 67.6% sensitivity, 73.9% specificity, and 69.6% accuracy in detecting type 2B or higher subscapularis tear. CONCLUSION: Patients with type 2A and 2B subscapularis tears (according to the Yoo and Rhee classification) showed differences in belly-press strength ratio, belly-press angle, and bear-hug test. The cutoff value of the 15° belly-press angle showed an accuracy of 69.6% in detecting subscapularis tears with type 2B or higher.

Intrawound Vancomycin Powder Application for Preventing Surgical Site Infection Following Cranioplasty.

OBJECTIVE: Surgical site infection is the most detrimental complication following cranioplasty. In other surgical fields, intrawound vancomycin powder application has been introduced to prevent surgical site infection and is widely used based on results in multiple studies. This study evaluated the effect of intrawound vancomycin powder in cranioplasty compared with the conventional method without topical antibiotics. METHODS: This retrospective study included 580 patients with skull defects who underwent cranioplasty between August 1, 1998 and December 31, 2021. The conventional method was used in 475 (81.9%; conventional group) and vancomycin powder (1 g) was applied on the dura mater and bone flap in 105 patients (18.1%; vancomycin powder group). Surgical site infection was defined as infection of the incision, organ, or space that occurred after cranioplasty. Surgical site infection within 1-year surveillance period was compared between the conventional and vancomycin powder groups with logistic regression analysis. Penalized likelihood estimation method was used in logistic regression to deal with zero events. All local and systemic adverse events associated with topical vancomycin application were also evaluated. RESULTS: Surgical site infection occurred in 31 patients (5.3%) and all were observed in the conventional group. The median time between cranioplasty and detection of surgical site infection was 13 days (range, 4-333). Staphylococci were the most common organisms and identified in 25 (80.6%) of 31 cases with surgical site infections. The surgical site infection rate in the vancomycin powder group (0/105, 0.0%) was significantly lower than that in the conventional group (31/475, 6.5%; crude odds ratio [OR], 0.067; 95% confidence interval [CI], 0.006-0.762; adjusted OR, 0.068; 95% CI, 0.006-0.731; p=0.026). No adverse events associated with intrawound vancomycin powder were observed during the follow-up. CONCLUSION: Intrawound vancomycin powder effectively prevented surgical site infections following cranioplasty without local or systemic adverse events. Our results suggest that intrawound vancomycin powder is an effective and safe strategy for patients undergoing cranioplasty.

Arthroscopic Incomplete Rotator Cuff Repair With Patch Augmentation Using Acellular Dermal Matrix Allograft.

Arthroscopic rotator cuff repair has been shown promising clinical outcomes. However, large to massive rotator cuff tears are difficult to completely repair with appropriate tension because of their size or poor tissue quality. An incomplete repair using the "hybrid technique" is one of way to solve this problem by maximizing the contact area between the tendon and the footprint of greater tuberosity. Additionally, the acellular dermal matrix patch augmentation has emerged as an adjuvant technique to enhance the biomechanical properties to promote healing of the repaired construct. This Technical Note describes arthroscopic incomplete rotator cuff repair using the "hybrid technique" with acellular dermal matrix patch augmentation.

Imaging Features and Pathological Correlation in Mixed Microcystic and Angiomatous Meningioma: A Case Report.

Meningiomas are the most common intracranial tumors. However, microcystic and angiomatous meningiomas are very rare subtypes that present unusual imaging findings. Hence, radiological diagnosis of these tumors can be challenging. We herein describe a case of mixed angiomatous and microcystic meningioma in an 81-year-old male. MRI revealed an extra-axial mass with high T2 signal intensity, measuring 1.5 cm in diameter, with multiple tiny intralesional cysts and entrapped peritumoral cyst formation. After tumor resection, a histopathological diagnosis of mixed angiomatous and microcystic meningioma was made.

Proximal tibia with an inserted nail can be an available donor site for harvesting cancellous bone.

INTRODUCTION: A pre-existing implant at the harvesting site might dissuade the surgeon from considering the site as available for bone harvesting. This study aimed to investigate the quantity of cancellous bone graft that can be harvested from a proximal tibia with an inserted nail and to report the clinical outcomes of this bone graft harvesting technique. HYPOTHESIS: Our hypothesis was that a certain amount of cancellous bone graft could be harvested from a proximal tibia with an inserted nail without compromising the surrounding environment and outcome of nonunion treatment. MATERIAL AND METHODS: Bone grafting from an ipsilateral proximal tibia with an inserted nail was performed in 32 patients for treating defect nonunion. The amount of harvested bone was measured using three parameters (weight, height, and volume). The effects of the proximal locking screw position on the quantity and location of bone graft harvest were analyzed. Clinical outcomes were evaluated by assessing the radiologic healing of the bone graft site and by assessing the donor site complications. RESULTS: The mean bone defect volume in the nonunion site was 31.1±18.3 (range, 10.6-87.0) cm3. The mean quantity of harvested bone from proximal tibias with an inserted nail was 21.2g, height was 3.9cm, and volume was 26.3 cm3. A positive correlation was found between the quantity of harvested bone and the level of the lateral oblique interlocking screw hole in the tibial nail. All grafted bone successfully consolidated in all cases at an average of 5.8 months postoperatively. However, joint penetration during bone harvesting occurred in one case. DISCUSSION: The bony defect, which measured about 14.3 cm3 could be filled with cancellous bone from a PT with an existing IM nail, without additional bone graft requirements. Even if an intramedullary nail exists inside the proximal tibia, harvesting cancellous bone at this site can be a viable option without serious complications. LEVEL OF EVIDENCE: IV; Retrospective descriptive study.

Redislocation after Bearing Exchange for the Treatment of Mobile Bearing Dislocation in Medial Unicompartmental Knee Arthroplasty.

PURPOSE: This study was conducted to investigate the outcomes of bearing exchange for the treatment of mobile bearing dislocation in medial unicompartmental knee arthroplasty (UKA). MATERIALS AND METHODS: We retrospectively reviewed 18 patients (15 females and 3 males, mean age of 65 years) treated with bearing exchange following mobile bearing dislocation in medial UKA. The occurrence of bearing redislocation, the Oxford Knee Score, and radiographic changes at the last follow-up were investigated. RESULTS: Bearing redislocation after bearing exchange occurred in 9 of 18 patients (50%). Of these 9 patients, 7 underwent conversion to total knee arthroplasty after bearing redislocation. The 9 patients without bearing redislocation showed good to excellent clinical outcomes at a mean follow-up of 55 months after bearing exchange. The non-redislocation group had a higher percentage of posterior dislocation of the bearing than the redislocation group (55.5% vs. 22.2%, p=0.040). Univariate logistic regression analysis showed no significant risk factors for bearing redislocation. CONCLUSIONS: This study showed a high rate of bearing redislocation after isolated, mobile bearing exchange for bearing dislocation following medial UKA. Therefore, bearing exchange as a sole treatment should be carefully considered in selected patients with correctable causes of bearing dislocation.

Increased Serum Ion Levels After Ceramic-on-Metal Bearing Total Hip Arthroplasty: Influence of an Asian Lifestyle.

BACKGROUND: Recent clinical studies have suggested that systemic metal ion levels are significantly elevated at midterm follow-up in patients with ceramic-on-metal (COM) bearing. However, it is not clear whether there is a correlation between patient-related factors including the lifestyle and elevated levels of serum metal ions following COM total hip arthroplasty (THA). METHODS: Serum metal levels were measured in 201 patients (234 hips) including 121 COM patients (140 hips) and 80 non-COM patients (94 hips). The Harris Hip Score, University of California, Los Angeles activity scale score, and Western Ontario and McMaster Universities Osteoarthritis Index score were measured and radiographs were obtained for the analysis. RESULTS: Significantly higher levels of cobalt (Co) and chromium (Cr) were detected in the serum of the COM THA group (Co: 1.86 ± 4.0 µg/L; Cr: 1.81 ± 2.87 µg/L) than those of the non-COM THA group (Co: 0.27 ± 0.14 µg/L; Cr: 0.19 ± 0.25 µg/L; P < .001). The serum metal levels of patients who achieved the squatting position and the kneeling position were significantly higher than those of patients who could not squat (Co: P = .033; Cr: P = .074) and kneel (Co: P = .049; Cr: P = .031). The metal ion levels of the COM THA group correlated with the total range of motion (Co: P = .0293; Cr: P = .0399). CONCLUSION: Patients who underwent a 36-mm COM THA showed high serum metal levels although good clinical outcomes at the midterm follow-up. We found that COM THA patients who were capable of greater range of motion, squatting, and kneeling are at risk of metal ion-related problems.

Gradual Height Decrease of Augmented Vertebrae after Vertebroplasty at the Thoracolumbar Junction.

OBJECTIVE: Vertebroplasty is an effective treatment for vertebral compression fracture, but may progress gradual vertebral height decrease in spite of vertebroplasty. Gradual vertebral height decrease also may induce aggravation of kyphotic change without severe pain. The purpose of this study was to evaluate risk factors for gradual vertebral height decrease in the absence of recurrent severe back pain. METHODS: A retrospective analysis was performed on 44 patients who were diagnosed with a first osteoporotic compression fracture at a single level at the thoracolumbar junction. All patients were taken vertebroplasty. Possible risk factors for gradual vertebral height decrease, such as sex, age, bone mineral density, body mass index, level of compression fracture, volume of injected cement, cement leakage into disc space, and air clefts within fractured vertebrae, were analyzed. RESULTS: Gradual vertebral height decrease of augmented vertebrae occurred commonly when more than 4 cc of injected cement was used, and when air clefts within fractured vertebrae were seen on admission. In addition, the sagittal Cobb angle more commonly increased during the follow-up period in such cases. CONCLUSION: Injection of more than 4 cc of cement during vertebroplasty and air cleft within fractured vertebrae on admission induced gradual vertebral height decrease in augmented vertebrae. Thus, longer follow-up will be needed in such cases, even when patients do not complain of recurrent severe back pain.

Clinical Features of Post-Traumatic Syringomyelia.

OBJECTIVE: The purpose of this study was to analyze the clinical manifestations, radiological findings, treatment results, and clinical significance of post-traumatic syringomyelia (PTS). METHODS: We retrospectively reviewed the medical charts of nine surgical patients with symptomatic PTS between 1992 and 2012. RESULTS: The most common clinical manifestation was development of new motor weakness. The mean interval between the initial injury and the onset of new symptoms 21.9 years. The mean length of the syringes observed on preoperative magnetic resonance images was 7.8 spinal levels. Shunting procedures were performed in five patients. Four patients underwent arachnoidolysis and duraplasty. Patients developed mechanical shunt failure. Postoperatively, one patient showed clinical improvement, four patients were stable, and four patients showed deterioration. CONCLUSION: PTS is a disabling sequelae of spinal cord injury, which develops months to years after spinal injury. We have to consider that patients with PTS may have poor long-term outcome.

Traumatic Spinal Subdural Hematoma with Intracranial Subdural Hematoma.

Traumatic spinal subdural hematoma associated with intracranial subdural hematoma is a rare condition. Herein, we report the case of a 62-year-old man with lower back pain, radiating pain, and numbness in both lower extremities, without motor weakness, for 2 weeks. Lumbar magnetic resonance imaging (MRI) revealed high signal intensity on T1-weighted image (WI), and low signal intensity on T2-WI from L2 to L5. Two weeks after conservative management, follow-up lumbar MRI did not show the hematoma and his symptoms were relieved and there was no neurological deficit; therefore, he was discharged. However, subsequently, intracranial subdural hematoma increased and upper extremity motor weakness appeared. This was treated surgically. If there is no neurological deficit, conservative treatment may be a good option. Follow-up evaluation for asymptomatic cranial subdural hematoma is necessary.

Shape memory characteristics and superelasticity of Ti-Ni-Cu alloy ribbons with nano Ti2Ni particles.

Microstructures and deformation behaviour of Ti-45Ni-5Cu and Ti-46Ni-5Cu alloy ribbons prepared by melt spinning were investigated by transmission electron microscopy, thermal cycling tests under constant load and tensile tests. Spherical Ti2Ni particles coherent with the B2 parent phase were observed in the alloy ribbons when the melt spinning temperature was higher than 1773 K. Average size of Ti2Ni particles in the ribbons obtained at 1873 K was 8 nm, which was smaller than that (10 nm) in the ribbons obtained at 1773 K. Volume fraction of Ti2Ni phase in the ribbons obtained at 1873 K was 40%, which was larger than that (20%) in the ribbons obtained at 1773 K. The stress required at temperatures of Af + 10 K for the stress-induced martensitic transformation increased from 93 MPa to 229 MPa and apparent elastic modulus of the B2 parent phase increased from 56 GPa to 250 GPa with increasing the melt spinning temperature from 1673 K to 1873 K in Ti-45Ni-5Cu alloy ribbons. The critical stress for slip deformation of the ribbons increased by coherent Ti2Ni particles, and thus residual elongation did not occur even at 160 MPa, while considerable plastic deformation occurred at 60 MPa in the ribbons without Ti2Ni particles. Almost perfect superelastic recovery was found in the ribbons with coherent Ti2Ni particles, while only partial superelastic recovery was observed in the ribbons without coherent Ti2Ni particles.