How shoulder immobilization after surgery influences daily activity - a prospective pedometer-based study.

PURPOSE: Immobilization, especially of the lower extremity, after orthopaedic surgery has been associated with reduced physical activity. Previous interventions from our study group showed even in young, healthy people reduced activity levels after immobilization of the shoulder. Therefore, this study investigates the change in physical activity due to shoulder immobilization after a reconstructive surgery. METHODS: This prospective study includes 40 patients undergoing surgery from May 2019 to December 2020. Daily activity was measured before surgery, after discharge and three weeks postoperatively each time for six days. Activity including step counts and active time were measured by Fitbit™ inspire. Range of motion before and after surgery as well as Pain (VAS) were documented. RESULTS: Steps became significantly less immediately postoperatively with an immobilized shoulder joint than before surgery (9728.8 vs. 6022.6, p < 0.05). At follow-up, the number of steps increased again, but still showed a significantly lower number of steps (mean 8833.2) compared to preoperative. Patients preoperatively showed mostly an "active" activity pattern, whereas postoperatively a "low active" behaviour predominated. The proportion of sedentary behaviour ("basal activity" and "limited activity") was almost three times higher postoperatively (12.5% vs. 30%). CONCLUSION: General physical activity is restricted during upper limb immobilization in adults. Therefore, activity-enhancing measures should be implemented in the early phase of rehabilitation after upper extremity surgery.

Prevalence of Musculoskeletal Diseases of the Upper Extremity Among Dental Professionals in Germany.

OBJECTIVE: Although many findings on occupational musculoskeletal complaints are available from American and European dentists, the corresponding data from Germany are still scarce. Therefore, the aim of this study was to provide additional information on the prevalence of and risk factors for musculoskeletal disorders of the upper extremity, particularly the shoulder in this specific population. METHODS: A written survey was carried out among 600 dentists in the state of North Rhine-Westphalia, Germany. Questionnaire items included physical and psychosocial workload, general health, and the occurrence of musculoskeletal symptoms during the previous 12 months that led to sick leave and medical care according to a modified version of the Nordic Musculoskeletal Questionnaire (NMQ). Regression analysis was used to evaluate relevant risk factors for severe musculoskeletal disorders. RESULTS: A total of 229 dentists were participated in the study (response rate 38%). Overall, 92.6% of the participants had already suffered from musculoskeletal symptoms in at least one body region. Symptoms were mostly reported in the neck (65.1%) and in the shoulder (58.1%). Limitations in daily activities were experienced by 15.9% due to neck pain and by 15.4% due to shoulder pain. Medical care was sought by 23.7% because of neck pain and by 21.1% due to shoulder pain. Risk factors for symptoms in the upper extremity regions were gender (female), increased physical load, and numerous comorbidities. CONCLUSION: There is a high prevalence of musculoskeletal disorders among dentists. Suitable interventions are therefore needed to prevent musculoskeletal diseases and pain among dental professionals, with particular attention to female dentists.

Clinical Outcome of Two-Stage Revision after Periprosthetic Shoulder Infection.

BACKGROUND: Periprosthetic shoulder infections are devastating complications after shoulder arthroplasty. A potential treatment concept is a two-stage prosthesis exchange. Data are sparse in terms of clinical outcome, including infection-free survival and patient satisfaction after this procedure. In the present study, we investigated recurrence of infection, revision-free survivorship and clinical outcome following two-stage revision due to periprosthetic shoulder infection. Furthermore, reasons for poor outcome were analyzed. METHODS: Sixteen patients undergoing two-stage revision after shoulder joint infection were retrospectively identified. Recurrence of infection was analyzed by Kaplan-Meier survival curve. Clinical outcome was quantified with subjective shoulder value (SSV), "quick" Disabilities of the Arm, Shoulder and Hand (qDASH) and Rowe score. Range of motion (ROM) was measured pre- and postoperatively. Postoperative scores and ROM were compared in a subgroup analysis according to different reimplanted prosthesis types. RESULTS: The reinfection-free implant survival was 81% after one year and at final follow-up (FU; mean of 33.2 months). The overall revision-free survival amounted to 56% after one year and at final FU. Patients who received reverse shoulder arthroplasty (RSA) as part of reimplantation had less disability and long-term complications. This group demonstrated better subjective stability and function compared to patients revised to megaprostheses or large-head hemiarthroplasties. CONCLUSIONS: Two-stage revision following periprosthetic joint infection of the shoulder allows appropriate infection control in the majority of patients. However, the overall complications and revision rates due to mechanical failure or reinfection are high. Reimplantation of RSA seem superior to alternative prosthesis models in terms of function and patient satisfaction. Therefore, bone-saving surgery and reconstruction of the glenoid may increase the likelihood of reimplantation of RSA and potentially improve outcome in the case of infection-related two-stage revision of the shoulder.

Single-row vs. double-row refixation of the subscapularis tendon after primary anatomic shoulder arthroplasty.

BACKGROUND: The postoperative integrity of the subscapularis tendon after primary anatomical shoulder arthroplasty has a significant effect on postoperative results. A transosseus Single Row Refixation technique (SRR) has shown up to 30% of partial tears in literature, a modified Double Row Refixation technique (DRR) has biomechanically shown a significantly reduced tear rate, but is yet to be proven in a clinical setting. Thus, we compared the SRR to the DRR technique using clinical outcome parameters and ultrasound examination. MATERIALS AND METHODS: 36 patients (40 shoulders; 20f, 16 m; øage: 66 years) were included in our retrospective cohort study. 20 shoulders were treated with the SRR technique (12f, 8 m; FU ø40.9 months) and 20 with the DRR technique (11f, 9 m; FU ø31.6 months). The SRR was performed with three to five transosseus mattress sutures. DRR consisted of two medial placed transosseus sutures and four laterally placed single tendon-to-tendon sutures. The postoperative subscapularis integrity was evaluated by ultrasound examination, the clinical outcome was assessed with the Constant-Murley Score (CS) and the American Shoulder and Elbow Surgeons Score (ASES). RESULTS: The subscapularis tendon was intact in 14 patients (70%) after SRR, whereas 18 patients (90%) treated with the DRR demonstrated a sonographically intact postoperative subscapularis tendon. The CS was 61.4 points in the SRR cohort and 67.3 points in the DRR cohort (p = 0.314). No significant differences were found in both cohorts preoperative (øSRR: 21.3 points; øDRR: 16.2 points, p = 0.720) and postoperative absolute ASES Scores (øSRR: 70.2 points; øDRR: 73.0 points, p = 0.792). However, the DRR cohort showed a statistical tendency to a higher postoperative ASES increase than the SRR cohort (øSRR-ASES increase: 48.9 points; øDRR-ASES increase: 56.8 points, p = 0.067). CONCLUSION: The results of this study show that application of the DRR technique can significantly reduce the total rate of postoperative subscapularis tears what effects a clinical tendency towards higher ASES improvements and a better range of motion compared to the SRR technique.

Postoperative Trends of Serum C-Reactive Protein Levels after Primary Shoulder Arthroplasty-Normal Trajectory and Influencing Factors.

Background-Postoperative serum C-reactive protein (CRP) is an important diagnostic parameter for systemic inflammation and reflects surgical trauma. While trends and normal trajectories after total knee (TKA) or hip arthroplasty (THA) are established, there is no reference standard for shoulder arthroplasty (SA). Therefore, the aim of this study was to research CRP trends and influencing factors following SA. Methods-This retrospective study analyzed postoperative serum CRP levels and trajectories in 280 patients following SA. Influence of prosthesis design, sex, operating time, BMI, and humeral augmentation with bone cement were analyzed using descriptive statistics and (non-) parametric testing. Results-There is a CRP trend with a peak on day two or three, with a subsequent decrease until day seven. Reverse and stemmed prostheses show a statistically higher CRP peak than stemless prostheses or hemiarthroplasties (HA). There was no influence of gender, body mass index (BMI), operating time, or bone cement. Conclusion-The presented findings may contribute to a better understanding of the postoperative CRP course after SA. The results of this retrospective study should be validated by a prospective study design in the future.

Long-term outcome of arthroscopic debridement of massive irreparable rotator cuff tears.

OBJECTIVES: To evaluate the clinical and radiographic outcome of low-demand patients with massive rotator cuff tears undergoing arthroscopic debridement in mid- and long-term follow-up, as well as the rate of conversion to reverse shoulder arthroplasty. METHODS: We performed a retrospective analysis of 19 patients with a mean age at surgery of 68 years (range, 55-80 years) from a previously described consecutive cohort and after a mean follow up of 47 month (FU1) and 145 month (FU2). The functional outcome was evaluated with the VAS score, the American Shoulder and Elbow Surgeons (ASES) score, and the age- and gender-adjusted Constant (aCS) score. The radiographic outcome was classified according to the Hamada classification. Non-parametric analyses were carried out with the Mann-Whitney U for independent samples and the Wilcoxon signed-rank test for related samples. RESULTS: Five patients (26%) developed symptomatic cuff tear arthropathy and underwent reverse shoulder arthroplasty after a mean time of 63 months (range, 45-97 months). These patients were excluded from further analyses. The mean VAS score of the remaining 14 patients at FU1 was significantly lower compared to preoperatively (P = .041), while there were no significant differences between the VAS score at FU1 and FU2 (P = 1.0). The ASES score of the affected shoulder at FU1 was significantly higher compared to prior to surgery (P = .028), while there were no significant differences between the scores of the affected shoulder between FU1 and FU2 (P = .878). While the ASES score of the contralateral shoulder at FU1 was significantly higher than the score of the affected shoulder (P = .038), there were no significant differences in the ASES scores of the affected and the healthy shoulder at FU2 (P = .575). The evaluation of the aCS produced similar results. A progression of the Hamada grade was documented in 6 patients. CONCLUSIONS: Arthroscopic debridement is a safe and valid option for low-demand middle-age or elderly patients with symptomatic massive rotator cuff tears, leading to a significant pain relief and significantly improved functional outcome at mid- and long-term follow up. However, about a quarter of the patients in our cohort had to undergo reverse shoulder arthroplasty due to symptomatic cuff tear arthropathy. Furthermore, some of the remaining patients continued to undergo radiographic progression. This might be due to the natural history of their disease and/or the surgical procedure, and the clinical relevance of this finding should be evaluated in further studies.

Skills in Open Surgery do not Predict Arthroscopic Skills in Medical Students.

OBJECTIVE: Teaching of basic open surgical skills like skin closure has been well established in medical schools' surgical curricula. The same cannot be said for basic arthroscopic skills even though the importance of arthroscopic surgery in Orthopaedics has been well documented. The goal of this study was to evaluate the relationship between basic skills in open surgery and basic arthroscopic skills in a cohort of medical students. Our hypothesis was that performance in open surgical skills does not correlate with skills in arthroscopic surgery. DESIGN: The performance of medical students in basic tasks in open surgery (porcine model: subcutaneous and skin suturing) and arthroscopic surgery (bench top model: arthroscopic triangulation and object transfer) was assessed. For both surgical techniques an introductory course was given followed by a standardized assessment. After 1 week both open and arthroscopic tasks were reassessed. All procedures were recorded and scored by 2 independent observers in a blinded fashion. SETTING: The study was performed at the skills lab of the Clinic for Orthopaedics and Tumororthopaedics at University Hospital Muenster in Muenster Germany. PARTICIPANTS: A cohort of 21 medical students (average age 22.2 years) participated in this study. The cohort consisted of 17 female (81%) and 4 male (19%) students. All students were in the clinical part of their study and had not received any prior surgical education. RESULTS: Interobserver reliability was very high for the arthroscopic tasks and high for the open surgery tasks. No correlation was found between open and arthroscopic skills. For the first assessment the correlation coefficient was r = 0.197 (p = 0.391). For the second assessment the correlation coefficient was r = 0.212 (p = 0.356). Significant improvement from first to second assessment was only found for the arthroscopic tasks (p < 0.0001) while improvement in the open surgery performance failed to reach statistical significance (p = 0.184). CONCLUSIONS: The results of this study suggest that performance in open surgical skills does not correlate with performance in arthroscopic skills and should be taught independent from each other. Arthroscopic skills can effectively be taught with bench top training systems in a time- and resource efficient manner, with measurable results even in a 1-day-course setup. Arthroscopic skills training may be offered in undergraduate curricula in addition to open surgical skills training to students with an interest in Orthopaedics.

How shoulder immobilization influences daily physical activity - an accelerometer based preliminary study.

BACKGROUND: To investigate the influence of shoulder immobilization on daily physical activity. INTRODUCTION: The harmful effect of sedentary behavior does not receive much attention in orthopedic surgery even though immobilization, especially of the lower extremity, has been associated with reduced physical activity. Immobilization of the shoulder is common after reconstructive shoulder surgery and could also potentially lead to reduced physical activity and have a negative effect on a patient's general health. METHOD: Twenty-one healthy volunteers were immobilized in an orthosis (DJO Ultrasling III) for 10 h on two consecutive days. In the following week, activity was measured on the same days without the orthosis. Activity including gait cycles per minute and total gait cycles per day was measured by accelerometer based step count StepWatchTMActivity Monitor. Average age was 26 +/- 3 years. A questionnaire was administered to evaluate subjective activity. RESULTS: Participants wearing the shoulder orthosis were significantly less active than without immobilization by 2227.5 gait cycles/day (5501.2 with SO, 7728.7 without SO). Also, significantly more time in sedentary behavior occurred (< 400 steps/h) when the shoulder was immobilized. Patients were significantly more active without shoulder orthosis in medium level activities (800-999 steps/h). Differences for low (400-799 steps/h) and high activity levels (> 1000 steps/h) were not statistically significant. Subjective limitations while wearing the orthosis were graded at 2.343 on a scale of 0-4. CONCLUSION: Results of this study show that even in young, healthy volunteers immobilization of the shoulder in an orthosis for 2 days leads to significantly reduced activity levels. A negative influence on general health, especially in older patients who are immobilized for up to 6 weeks, can potentially occur. Promoting physical activity during the immobilization period should be part of rehabilitation after injuries/surgery of the shoulder. TRIAL REGISTRATION: Retrospectively registered in DRKS (DRKS00017636).

Subtle changes of gray matter volume in fibromyalgia reflect chronic musculoskeletal pain rather than disease-specific effects.

Fibromyalgia syndrome (FMS) is a chronic pain syndrome. Neuroimaging studies provided evidence of altered gray matter volume (GMV) in FMS but, similarly, in chronic pain of other origin as well. Therefore, the purpose of this study was to evaluate the disease specificity of GMV alterations in FMS by direct comparison. Structural MRI data of the brain were acquired in 25 females with FMS and two different control groups: 21 healthy subjects and 23 patients with osteoarthritis. Regional GMVs were compared by voxel-based morphometry and additional ROI-analyses. In conclusion, we did not identify significant GMV alterations in either FMS or OA patients compared to healthy controls when adopting a conservative statistical approach with multiple comparison correction. However, even under a more liberal approach no FMS-specific GMV changes were found because both pain groups presented increased gray matter volumes in the precentral gyrus and decreased GMV in the angular gyrus/middle occipital gyrus and middle temporal gyrus in comparison with healthy controls. Since no differences between both pain groups could be detected cortical GMV changes in FMS should not be interpreted as FMS-specific but might rather reflect changes in chronic pain in general. This previously held notion is confirmed in this study by direct comparison with a control group consisting of another pain disorder.

Adaptive Changes on the Dominant Shoulder of Collegiate Handball Players-A Comparative Study.

Vogler, T, Schorn, D, Gosheger, G, Kurpiers, N, Schneider, K, Rickert, C, Andreou, D, and Liem, D. Adaptive changes on the dominant shoulder of collegiate handball players-A comparative study. J Strength Cond Res 33(3): 701-707, 2019-Handball players are susceptible to adaptive bony and soft-tissue changes of the dominant shoulder. Our goal was to compare the glenohumeral range of motion and posterior capsule thickness between the dominant and nondominant arm of throwing athletes and between the dominant arm of nonthrowers and throwing athletes. Twenty-three collegiate handball players and 23 nonthrowing athletes underwent an examination of the dominant and the nondominant shoulder. Humeral retroversion and posterior capsule thickness were assessed with an ultrasound examination, whereas external rotation and internal rotation were determined with a digital inclinometer. The dominant shoulder of handball players had a significantly higher external rotation compared with their nondominant shoulder and the dominant shoulder of nonthrowing athletes. Furthermore, the dominant shoulder of handball players had a significantly lower internal rotation compared with their nondominant shoulder, with no differences compared with the dominant shoulder of the nonthrowing athletes. There was a trend for an increased posterior capsule thickness and an increased humeral retroversion between the dominant and the contralateral shoulder of handball players. Moreover, we found a significant increase in the capsule thickness of the dominant shoulder of throwing athletes compared with the dominant shoulder of nonthrowers. However, there were no differences in humeral retroversion. Our analysis suggests that a comparison of the dominant shoulder of overhead throwing athletes with the dominant shoulder of nonthrowing athletes might be more appropriate than the comparison of the dominant and the nondominant shoulder to evaluate the adaptive changes on the dominant side.

Megaprosthetic replacement of the distal humerus: still a challenge in limb salvage.

BACKGROUND: The distal humerus is a rare location of bone tumors. Because of the complexity of the elbow joint, poor soft-tissue coverage, and proximity of nerves and vessels, resection and endoprosthetic reconstruction are demanding. METHODS: This retrospective study evaluated the clinical results after distal humeral resection and megaprosthetic reconstruction in 12 patients with an average age of 46 years. All patient files were reviewed for clinical information, and postoperative function and patients' contentment were assessed using the Musculoskeletal Tumor Society score. RESULTS: The predominant diagnoses were bone and soft-tissue sarcoma (n = 6), giant cell tumor (n = 2), and renal cell carcinoma metastasis (n = 2). Local recurrence was the reason for secondary amputation in all cases (n = 3). The prosthetic survival rate after surgery was 82% at 2 years and 64% at 5 years. Reconstruction failure was mainly caused by aseptic loosening of the humeral stem, occurring in 27% (n = 3), followed by aseptic loosening of the ulnar stem in 9% (n = 1) and periprosthetic infection in 9% (n = 1). The mean Musculoskeletal Tumor Society score was 24 points (range, 20-30 points). An extension lag of more than 10° was noted in 6 patients (55%). CONCLUSION: Our results suggest that limb salvage with a distal humeral replacement can achieve good functional results in most patients, although the complication rate with special emphasis on the loosening rate of the humeral stem is high. However, limb salvage was not achieved in 27% of patients because of local recurrence.

Risk factors for acute injuries and overuse syndromes of the shoulder in amateur triathletes - A retrospective analysis.

OBJECTIVES: To investigate the prevalence of shoulder-related acute and overuse injuries in triathletes and examine the role of possible risk factors, in order to identify potential preventive measures. METHODS: We performed a retrospective epidemiologic study of 193 amateur triathletes between June and August 2013 and evaluated their competition and training habits, as well as the presence of acute and overuse injuries of the shoulder sustained during the past 12 months. Contingency tables were analyzed using Pearson's chi-squared test. Normally distributed data were compared with the independent samples t-test, while non-parametric analyses were performed with the Mann-Whitney U test. Binary logistic regression was used to identify important predictors of injuries. RESULTS: 12 participants (6%) sustained acute injuries and 36 athletes experienced an overuse injury. The acute injury rate amounted to 0.11 per 1000 hours of training and the overuse injury rate to 0.33 per 1000 hours of training. There was no association between athletes' age, height, weight, BMI, a history of shoulder complaints or triathlon experience in years and acute or overuse injuries. Male athletes had a trend for sustaining more acute injuries then female athletes (8% vs. 2%, p = 0.079). Athletes with acute injuries spent a significantly higher amount of time per week doing weight training (p = 0.007) and had a trend for a higher weekly duration of cycling training (p = 0.088). Athletes with overuse injuries participated in a significantly higher number of races compared to athletes without overuse injuries (p = 0.005). The regular use of paddles was associated with a significantly higher rate of overuse injuries (24% vs. 10%, p = 0.014). CONCLUSION: The regular use of paddles during swimming training appears to be a risk factor for the development of overuse injuries, while an increased duration of weight and cycling training seems to be associated with a higher rate of acute injuries.

Long-term outcomes after combined arthroscopic medial reefing and lateral release in patients with recurrent patellar instability - a retrospective analysis.

BACKGROUND: There is currently no consensus regarding the optimal surgical treatment method for patients with recurrent patella instability. Our goal was to evaluate the long-term results of combined arthroscopic medial reefing and lateral release, to identify possible risk factors for recurrent dislocations and residual complaints after surgical treatment and to assess functional outcome. METHODS: We performed a retrospective study of 38 patients (43 knees) treated with all-inside technique between 2001 and 2010. The functional outcome was evaluated with the Kujala score, while pain intensity was scored on a visual analogue scale (VAS). Contingency tables were analysed with Fisher's exact test. Non-parametric analyses were carried out with the Mann-Whitney U and the Wilcoxon signed-rank test. Survival curves were calculated with the Kaplan-Meier method and compared with the log-rank test. RESULTS: The median age at surgery was 16 years (range, 9-44 years) and the median follow-up amounted to 9.7 years (range, 4.7-14.7 years). Residual complaints were present in 34 cases (79%). Patients with residual complaints had a trend for a higher body mass index (BMI) at surgery (25.7 vs. 21.6, P = .086). Twenty-two cases had recurrent dislocation after a median interval of 30 months. The probability of recurrent dislocations amounted to 16% after 1 year and 52% after 10 years. There were no significant differences in the presence of residual complaints (P = .721) and median VAS score (P = .313) between patients with or without recurrent dislocation. Patients with recurrent dislocations had a trend towards younger age at surgery (15 vs. 18 years, P = .076). The median Kujala score of the affected knee was 81. Patients with recurrent dislocations had a significantly lower score compared to patients without recurrent dislocations (67 vs. 91, P < .001). CONCLUSIONS: The combined arthroscopic lateral release with medial reefing does not appear to be an adequate treatment for patients with chronic patellar instability in long-term follow-up. Younger patients might be at a higher risk for recurrent dislocations, while a higher BMI at surgery might be associated with residual complaints.

Risk of Engagement of Bipolar Bone Defects in Posterior Shoulder Instability.

BACKGROUND: The risk of re-engagement of bipolar bone defects in posterior shoulder instability has not yet been investigated. HYPOTHESIS: Posterior glenoid defects can lead to the engagement of supposedly noncritical reverse Hill-Sachs lesions (RHSLs). STUDY DESIGN: Descriptive laboratory study. METHODS: In a retrospective multicenter study, 102 cases of posterior shoulder dislocations and resulting RHSLs were collected. Of these cases, all patients with available computed tomography (CT) scans, with a reduced shoulder joint, and without bony posterior glenoid rim defects or concomitant dislocated fractures of the humeral head were included. The gamma angle (measure of the critical size and localization of RHSLs) and the delta angle (measure of the degree of internal rotation necessary for engagement to occur) of the RHSLs were determined on standardized CT scans. Virtual posterior glenoid defects were created, and the effect of increasing defect size on the delta angle was determined. RESULTS: The mean gamma angle of the 19 patients included in this study was 94.5° (range, 69.7°-124.8°). After creation of the virtual posterior glenoid defects, a mean reduction of the delta angle by 2.3° ± 0.2° (range, 1.9°-2.9°) per millimeter defect was observed. The cumulative change in the delta angle showed a highly significant correlation with the absolute and relative size of the glenoid defect ( R = 0.982, P < .001 and R = 0.974, P < .001, respectively). CONCLUSION: Concomitant posterior glenoid defects might lead to the engagement of noncritical RHSLs. When measuring the gamma angle to identify critical RHSLs, posterior glenoid bone loss should be accounted for.

Conversions from anatomic shoulder replacements to reverse total shoulder arthroplasty: do the indications for initial surgery influence the clinical outcome after revision surgery?

INTRODUCTION: The most frequent indications for anatomic shoulder replacement are glenohumeral osteoarthritis and fractures of the humeral head. If anatomic shoulder prostheses fail, reverse total shoulder arthroplasty is often the only remaining treatment option. This study evaluates the influence of indications for primary shoulder arthroplasty on the clinical outcome after conversion to reverse total shoulder arthroplasty. MATERIALS AND METHODS: From 2010 to 2012, 44 failed shoulder arthroplasties were converted to reverse total shoulder arthroplasty. Forty-four patients were available for follow-up after a mean of 24 months (14-36 months). Twenty-three of them had received an initial shoulder replacement because of osteoarthritis, while the remaining 21 patients had been treated for a fracture of the humeral head. At follow-up, patients were assessed with X-rays, constant-, and ASES scores. RESULTS: The total number of observed complications was higher in patients revised because of failed fracture arthroplasty (24 vs. 9%). Patients initially treated for osteoarthritis achieved a higher ASES score (71 vs. 59 points; p = 0.048). The normalized constant score was not different between the two observed groups (osteoarthritis 73% vs. fracture 67%: p = 0.45). Complications occurred more often in patients who had initially suffered from a fracture of the humeral head (fracture 23.8% vs. osteoarthritis 8.7%). Scapular notching was more frequent after initial fracture arthroplasty (33 vs. 14%). CONCLUSION: Indications for initial shoulder replacement have an influence on the clinical outcome after conversion to reverse total shoulder arthroplasty. Patients initially treated for a fracture of the humeral head have a lower subjective outcome and a higher complication rate in comparison with patients initially treated for osteoarthritis. LEVEL OF EVIDENCE: IV (Retrospective study).

Defect Characteristics of Reverse Hill-Sachs Lesions.

BACKGROUND: Little scientific evidence regarding reverse Hill-Sachs lesions (RHSLs) in posterior shoulder instability exists. Recently, standardized measurement methods of the size and localization were introduced, and the biomechanical effect of the extent and position of the defects on the risk of re-engagement was determined. PURPOSE: To analyze the characteristics and patterns of RHSLs in a large case series using standardized measurements and to interpret the results based on the newly available biomechanical findings. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: In this multicenter study, 102 cases of RHSLs in 99 patients were collected from 7 different shoulder centers between 2004 and 2013. Patient- as well as injury-specific information was gathered, and defect characteristics in terms of the size, localization, and depth index were determined on computed tomography or magnetic resonance imaging scans by means of standardized measurements. Additionally, the position (gamma angle) of the posterior defect margin as a predictor of re-engagement was analyzed. RESULTS: Three types of an RHSL were distinguished based on the pathogenesis and chronicity of the lesion: dislocation (D), locked dislocation (LD), and chronic locked dislocation (CLD). While the localization of the defects did not vary significantly between the subgroups (P = .072), their mean size differed signficantly (D: 32.6° ± 11.7°, LD: 49.4° ± 17.2°, CLD: 64.1° ± 20.7°; P < .001). The mean gamma angle as a predictor of re-engagement was similarly significantly different between groups (D: 83.8° ± 14.5°, LD: 96.5° ± 17.9°, CLD: 108.7° ± 18.4°; P < .001). The orientation of the posterior defect margin was consistently quite parallel to the humeral shaft axis, with a mean difference of 0.3° ± 8.1°. CONCLUSION: The distinction between the 3 different RHSL types based on the pathogenesis and chronicity of the defect helps identify defects prone to re-engagement. The gamma angle as a measurement of the position of the posterior defect margin and therefore a predictor of re-engagement varies significantly between the defect types.

The Coracohumeral Distance in Shoulders With Traumatic and Degenerative Subscapularis Tendon Tears.

BACKGROUND: A reduced coracohumeral distance (CHD) is thought to be responsible for subcoracoid impingement. This only accounts for degenerative tendon tears. In traumatic tears, the subcoracoid space should be normal. HYPOTHESIS: The CHD in patients with traumatic subscapularis tendon tears is larger than that in patients with degenerative tears and does not differ from patients with an intact subscapularis tendon. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 83 patients with arthroscopically certified subscapularis tendon tears were included in the study. Forty-four patients had degenerative causes (group 1), and 39 had traumatic causes (group 2). The control group consisted of 20 patients with traumatic supraspinatus tendon tears and arthroscopically proven, intact subscapularis tendons (group 3). On preoperative axial magnetic resonance imaging, the distance between the CHD was measured, and the values of the 3 groups were compared using the t test. RESULTS: The mean (±SD) CHD in patients with degenerative subscapularis tendon tears was 8.6 ± 2.0 mm (range, 4.0-13.2 mm) and was significantly (P = .0003) smaller than that in patients with traumatic tears (10.2 ± 2.0 mm; range, 6.6-16.2 mm) or controls (10.4 ± 1.8 mm; range, 6.8-14.0 mm). The CHD of controls and patients with traumatic tears did not differ significantly (P = .7875). A CHD of less than 6 mm only occurred in patients with degenerative subscapularis tendon tears. CONCLUSION: The hypothesis that the CHD in patients with degenerative subscapularis tendon tears is significantly smaller than that in patients with traumatic tears or intact subscapularis tendons was confirmed. The CHD in patients with traumatic tears does not differ from that in controls. A CHD of less than 6 mm only occurs in patients with degenerative subscapularis tendon tears.

Differences in acromial morphology of shoulders in patients with degenerative and traumatic supraspinatus tendon tears.

PURPOSE: Distinct characteristics of acromial morphology seem to be one factor for the development of degenerative supraspinatus tendon tears. Thus, it is questionable whether patients with traumatic tendon tears also present these parameters. The hypothesis of the present study was that the acromial morphology of patients with degenerative supraspinatus tendon tears differs from patients with traumatic tears. METHODS: One hundred and thirty-six patients that were treated by arthroscopic rotator cuff repair from 2010 to 2013 were included in this study. Seventy-two patients had degenerative (group 1), and 64 had traumatic (group 2) supraspinatus tendon tears. On preoperative radiographs the Bigliani type, acromial slope, acromiohumeral (AH) distance, lateral acromial angle (LAA), acromion index (AI), and critical shoulder angle (CSA) were measured. Medians of these parameters as well as of age of both groups were compared using the t test. RESULTS: The percentaged distribution of the Bigliani type differed (group 1 vs. 2: type 1: 18/38, type 2: 56/55, type 3: 26/8). All parameters showed significant differences between degenerative and traumatic tears. Slope: 21.2° (SD 7.6°) versus 19.2° (SD 7.9°, p = 0.026), AH distance: 8.4 mm (SD 2.3 mm) versus 9.9 mm (SD 1.9 mm, p = 0.0006), LAA: 77.0° (SD 4.0°) versus 82.5° (SD 4.7°, p < 0.0001), AI: 0.77 (SD 0.07) versus 0.73 (0.06, p = 0.0239), and CSA: 36.8° (SD 3.6°) versus 35.3° (SD 2.9°, p = 0.007). An LAA <70° or an AH distance of <5 mm only occurred in degenerative tears. Patients with degenerative tears were significantly older (60 vs. 54 years). CONCLUSIONS: The hypothesis that the acromial morphology of patients with degenerative supraspinatus tendon tears differs from patients with traumatic tears was confirmed. Shoulders with degenerative tears show a narrower subacromial space and a larger lateral extension as well as a steeper angulation of the acromion than with traumatic tears. Thus, the results of this study support the theory of external impingement as a cause for degenerative rotator cuff tears. LEVEL OF EVIDENCE: IV.

Cold versus cold compression therapy after shoulder arthroscopy: a prospective randomized clinical trial.

PURPOSE: Purpose of the present study was to investigate the acute effects of a cold compression bandage on pain, swelling and skin-surface temperature after the first 24 h after arthroscopic surgery of the shoulder in a stationary setting and to compare it with cold therapy using only a cold pack. It was hypothesized that using the bandage is more effective in reducing pain and swelling after 24 h compared with using only a cold pack. METHODS: Fifty-two patients (53 ± 12.2 years) were randomly assigned to two groups after arthroscopic surgery. The first group wore a cold compression bandage, and the second group a conventional frozen cold pack. Pain, swelling and skin-surface temperature were measured 2, 8 and 24 h after surgery. Differences within and between groups were analysed. RESULTS: Both groups showed a significant reduction of the circumference of the arm 15 and 20 cm proximal of the lateral epicondyle 24 h after surgery (cold compression: p = 0.003; p < 0.001; cold: p < 0.001). Pain at rest was significantly reduced with cold compression bandage 24 h after surgery (p = 0.001). Skin temperature increased in both groups 24 h after surgery (bandage: p < 0.001; cold pack: p = 0.002). After 24 h, pain during activity was significantly decreased in the group wearing the bandage compared with the group using the cold pack (p = 0.026). CONCLUSIONS: Based on the results of this study, no recommendation can be made with respect to the question whether cold compression therapy or cold therapy should be preferred immediately after arthroscopic surgery of the shoulder. Clinicians should question the need of expensive cold compression bandages in the short-term post-operative treatment after arthroscopic surgery of the shoulder. LEVEL OF EVIDENCE: II.