Shoulder and Elbow

96. 10-year follow-up of 1,371 acute proximal humeral fractures treated with stemmed hemiarthroplasty
Alexander Amundsen
Department of Orthopaedic Surgery, Herlev-Gentofte Hospital

Background: There is no consensus on the treatment of proximal humeral fractures. Hemiarthroplasty has been widely used in patients when non-surgical treatment is not possible. The short-term outcome is varying and there is, despite extensive use for many decades, limited information about the long-term outcomes.
Purpose / Aim of Study: To report the 10-year patient reported outcome and implant survival after acute proximal humeral fractures treated with hemiarthroplasty.
Materials and Methods: Data was obtained from the Danish Shoulder Arthroplasty Registry. The Western Ontario Osteoarthritis of the Shoulder (WOOS) index form was send to all patients 8 to 14 years after primary surgery. 1,371 patients with an acute proximal humeral fracture were treated with hemiarthroplasty between 2006-2010. 822 (60.0%) patients had died and 6 (0.4%) had emigrated. 549 patients were alive of which 38 (2.8%) were revised. Thus, 511 (37.3%) patients with a mean follow- up time of 10.7 (SD 1) years were available for analysis. 378 (74.0%) patients answered the 10- year follow-up with 339 (66.3%) having a complete questionnaire. The implant survival was calculated using the Kaplan-Meier method.
Findings / Results: Mean age at surgery was 67 years (SD 10) and 81 % (n=412) were women. Mean WOOS score was 65 (SD 26). Linear regression models found no statistically significant relationship between WOOS score and age, sex, prosthesis brand or year of surgery. The revision rate of the total study population was 4.5 % (n=62) and the cumulative implant survival rate was 94 % (95 % CI 93-96).
Conclusions: This is the largest long-term follow-up study of acute proximal humeral fractures treated with hemiarthroplasty. We found a low revision rate and a reasonable 10-year patient-reported outcome. The patient-reported outcome should be interpreted with caution as the patients are a selected population without any information about the large number of patients who died or did not return a complete WOOS score. However, the long-term outcome and revision rate suggest that hemiarthroplasty offers a valid alternative, when non-surgical treatment is not possible, in fracture patients with long life expectancy.

97. Implant migration, clinical outcome and revision rates following humeral head resurfacing: 9-13 years results from a randomized controlled clinical trial comparing two different implants
Mikkel Tøttrup, Janni Kjærgaard Thillemann, Theis Munchholm Thillemann, Inger Mechlenburg, Thomas Klebe, Kjeld Søballe, Maiken Stilling
Department of Ortopaedic Surgery, Aalborg University Hospital, Farsø; AutoRSA Research Group, Aarhus University Hospital; Department of Ortopaedic Surgery, Aarhus University Hospital; Department of Ortopaedic Surgery, Aarhus University Hospital; Elective Surgery Centre, Silkeborg Regional Hospital; Department of Ortopaedic Surgery, Aarhus University Hospital; Department of Ortopaedic Surgery, Aarhus University Hospital

Background: Humeral head resurfacing implants (HHRI) have been widely used due to theoretical advantages including restoration of anatomy, preservation of bone stock and a shorter operating time. Several studies have shown unacceptable revision rates of HHRI, but no previous studies have evaluated implant migration at mid-term follow-up and related migration patterns to revision at longer-term.
Purpose / Aim of Study: To compare implant migration, clinical outcome and revision rates of the Copeland and the Global C.A.P. HHRIs.
Materials and Methods: Thirty-one patients (13 women), mean age 63 years (range 39-82), with shoulder osteoarthritis were randomly allocated to a Copeland (Biomet) (n=13) or Global C.A.P. (DePuy) (n=18) HHRI. Patients were followed for 5 years with radiostereometry, Constant Shoulder Score (CSS), and the Western Ontario Osteoarthritis of the Shoulder Index (WOOS). Additionally, WOOS scores and revision status were obtained at 9-13 years follow-up.
Findings / Results: At the 5-year follow-up, total translation (TT) was 0.75 mm (95% CI: 0.53-0.97) for the Copeland HHRI and 1.15 mm (95% CI: 0.85-1.46) for the Global C.A.P. HHRI (p=0.04). The overall cumulative risk of revision at 5 years and at the latest available follow-up was 30% (95% CI: 17-49) and 47% (95% CI: 31-66), respectively, but there was no difference in risk of revision between the two implants at these timepoints (p>0.44). At the 1-year follow-up, HHRIs which were later revised, had a mean 0.53mm (95% CI: 0.18-0.88) higher TT compared to non-revised HHRIs. The migration pattern in revised HHRIs was medial translation and lift-off. Clinical scores and reasons for revision will be presented at DOS.
Conclusions: At 5-year follow-up, the Global C.A.P. HHRI displayed higher total translation than the Copeland HHRI but revision rates in this small cohort were similar. HHRIs, that were later revised, migrated more during the first postoperative year compared to non-revised implants. A cumulative revision risk of nearly 50% at the latest follow-up is higher than reported in the Danish Shoulder Arthroplasty Registry.

98. The incidence and epidemiology of acute acromioclavicular dislocations in the capitol region of Copenhagen
Kristine Bramsen Andersen, Klaus Bak, Kristoffer Seem, Per Hölmich, Kristoffer Weisskirchner Barfod
Department of orthopaedic surgery, Hvidovre Hospital; Department of orthopaedic surgery, Kysthospitalet; Department of orthopaedic surgery, Hvidovre Hospital; Department of orthopaedic surgery, Hvidovre Hospital; Department of orthopaedic surgery, Hvidovre Hospital

Background: Acromioclavicular joint (AC) dislocations are common injuries accounting for 9-12% of all injuries to the shoulder girdle. The frequency is widely reported in the literature; however only limited research is available that describes the incidence and basic epidemiological features of the injury in a general urban population.
Purpose / Aim of Study: To investigate and describe the incidence and epidemiology of acute acromioclavicular dislocations in the capitol region of Denmark
Materials and Methods: The study was designed as a prospective cohort study. All patients with an acute (<2 weeks) injury to the AC joint admitted to Copenhagen University Hospital Amager, Hvidovre and Glostrup from January 1st to December 31st 2019 were prospectively registered. The hospitals serve a population of 532.000 citizens. The patients were identified by evaluation of all x-rays of the AC-joint and clavicle obtained in the three Emergency Departments. Patients with trauma to the shoulder, pain from the AC-joint and increased coracoclavicular distance were included and classified according to Rockwood’s classification (type II-VI) by two independent raters. Rockwood type I was considered a sprain with no AC joint displacement and therefore not included. Data on age, gender, time of injury, affected side and mechanism of injury were registered.
Findings / Results: A total of 106 patients with mean age 40.2 years (range 19-77, SD 14.1) were included in the study. The incidence was 20 per 10^5 inhabitants per year. 95 patients were male and 11 were female giving a male-female ratio of 8.6:1. Rockwood type III was the most common type of AC joint dislocation accounting for 59/106 (55.7%) of the injuries. Type II and V accounted for 43 (40.6%) and 4 (3.8%). Type I was not included in the study and there was no type IV or VI dislocations. The most common mechanism of injury was sport 80/106 (75.5%). Cycling accounted for half of all injuries 51/106 (48%). The age distribution was bimodal with 31% of injuries occurring in age 18-29 years and 26% occurring in age 50-59.
Conclusions: Rockwood type III was the most common type of AC joint dislocation. Young and middle-aged men were at highest risk. 75% of the injuries occurred during sports most frequently within cycling.

99. Less than half of patients in secondary care adheres to clinical guidelines for subacromial impingement and have acceptable symptoms after treatment: A nationwide cohort study of 3306 patients
Mikkel Bek Clausen, Mikas Bjørn Merrild, Kika Holm, Mads Sorvad Pedersen, Lars Louis Andersen, Mette Kreutzfeldt Zebis, Thomas Linding Jakobsen, Kristian Thorborg
Department of Midwifery, Physiotherapy, Occupational Therapy and Psychomotor Therapy at Faculty of Health, University College Copenhagen; Department of Midwifery, Physiotherapy, Occupational Therapy and Psychomotor Therapy at Faculty of Health, University College Copenhagen; Department of Midwifery, Physiotherapy, Occupational Therapy and Psychomotor Therapy at Faculty of Health, University College Copenhagen; Department of Midwifery, Physiotherapy, Occupational Therapy and Psychomotor Therapy at Faculty of Health, University College Copenhagen; , National Research Centre for the Working Environment; Department of Midwifery, Physiotherapy, Occupational Therapy and Psychomotor Therapy at Faculty of Health, University College Copenhagen; 3. Section for Orthopaedic and Sports Rehabilitation (SOS-R), Health Centre Nørrebro, City of Copenhagen; 4. Sports Orthopedic Research Center – Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital, Amager-Hvidovre

Background: According to evidence-based guidelines for treatment of subacromial impingement (SIS), non-operative care with three months of exercise therapy is first line of treatment, but guideline adherence is unknown.
Purpose / Aim of Study: We investigated to what degree current care complies with clinical guidelines and to what extent successful outcomes are achieved.
Materials and Methods: We invited all 4521 patients diagnosed with SIS at any Danish hospital during a 3-months period to participate in this Nation-wide retrospective population-based cohort study. The questionnaire used to obtain patient-reported information on content of care was based on the Danish National Clinical Guidelines for treatment of SIS and referral guidelines. Nine members of the working group responsible for the National Clinical Guidelines, including three orthopedic surgeons, commented on the questionnaire. We developed a revised version based on systematic condensation of all comments. Participants also reported patient acceptable symptom-state. Invitations were sent to eligible patients 3.5 months after diagnosis at the hospital.
Findings / Results: In total, 3306 eligible patients completed the questionnaire at median 16.7 weeks after diagnosis at a hospital. In total, 44% had completed 12 weeks of exercise therapy, while 13% had not engaged with exercise therapy at all. The remaining patients had completed less than 12 weeks and were either still engaged with exercise therapy (13%) or had stopped (30%). From the full cohort, 21 % had underwent surgery for their shoulder condition at four months follow-up, with 40% of these reporting to have engaged with exercise therapy for 12 or more weeks before surgery. Exercise therapy most commonly included mobility (81%), strengthening (75%), stretching (67%), and posture correction/scapula setting (49%). Only 43% of patients undergoing non-operative care had reached acceptable symptom-state.
Conclusions: Less than half of patients diagnosed with subacromial impingement follow the clinical guidelines recommending three months of exercise therapy. Furthermore, less than half of the patients reaches an acceptable symptom-state. Future investigations should focus on the link between guideline adherence and treatment results.

100. The precontoured clavicle plate: clinical and radiological evaluation of two different generations of plates for 290 acute midshaft clavicle fractures
Ilija Ban, Zaid Issa , Anders Troelsen
Orthopaedic, Hvidovre Hospital; Orthopaedic, Køge Hospital; Orthopaedic, Hvidovre Hospital

Background: Primary surgical fixation of displaced midshaft clavicle fractures has significantly increased over the last decades. Precontoured locking plates has been used for many years and the plates have evolved over time with potential improvements to increase unions and lower complications.
Purpose / Aim of Study: Purpose of this study was primarily to compare two generations of precontoured clavicle plates
Materials and Methods: Retrospective chart and radiological review of 290 patients with acute displaced midtshaft clavicle fractures treated with an Acumed Clavicle plate (N=194 of previous generation plates and N=96 of current plates). The overall cohort had a mean age of 42.9 years (SD 14.6), the male:female ratio was 4:1 and 64% of the fractures was displaced in combination with a segmental fragment. 64% had DASH completed with an overall follow-up of 6.8 years (range 4.0-9.4)
Findings / Results: In general, no significant differences were found between the two plate generations in relation to all investigated outcomes. Implants were removed in 23.7% of all cases with the previous plate compared to 13.5% with the current lower profile plate (p=0.06). The overall union rate was 98.3%. A secondary surgical procedure was done in 24.8% of all cases with most due to implant related irritation resulting in implant removal (20.3%). Functionality measured by DASH was excellent at follow-up (median DASH 2 (range 0-63))
Conclusions: Using a precontoured clavicle plates to treat patienta with displaced clavicle fractures with precontoured clavicle plates seems to result in excellent union and function with few complications. Current generation of lower profile plates does not seem to improve clinical outcome compared to older plates but is seems that the percentwise risk of implant related discomfort is lower though the difference is not statistically significant

101. Is the quality of tension band wiring for olecranon fractures related to complications?
Kia Cirkeline Møller Hansen, Mustafa Sahid Mahamoud, Stefan Jensen, Bjarke Viberg
Department of Orthopaedic Surgery and Traumatology, Kolding Hospital and Hospital of South West Jutland; Department of Orthopaedic Surgery and Traumatology, Odense University Hospital ; Department of Orthopaedic Surgery and Traumatology, Kolding Hospital; Department of Orthopaedic Surgery and Traumatology, Kolding Hospital and Odense University Hospital

Background: Tension band wiring (TBW) is the most frequently used fixation for displaced olecranon fractures. TBW is in general terms known as a simple method that can be performed by most orthopaedic surgeons and has satisfying results.
Purpose / Aim of Study: The aim of this study was to determine if the quality of TBW for displaced olecranon fractures in adult patients were associated with an increase in complications.
Materials and Methods: From 2013 to 2018, eligible patients were retrieved using elbow and olecranon fracture diagnosis codes from the hospitals administration databases in the Region of Southern Denmark. Patients’ health care files were reviewed for demographics and complications. Major complication was defined as any reoperation within 8 weeks or deep infection. Any loss of fixation was added to define surgical complications. Pre- operative x-rays were reviewed for classification and postoperative x-rays were evaluated quality of TBW based on 10 imperfections and yielding 10 points if no imperfections were present. STATA was used for descriptive statistics with median and inter quartile range. Chi square test was used for group comparison.
Findings / Results: 305 patients were included, 208 (68%) females, median age was 64 (IQR=24), and 20% were ASA≥3. There were 76% Mayo type 2A and 20% type 2B. A postoperative cast applied for 96% of the patients for 2 (IQR=1) weeks. The TBW’s were rated with a median score of 8 points (IQR=2). There were 11.8% with major complications. No complications were seen if given 10 points and 15,4% if given 5 points thereby resulting in a clear relation between a higher score and less complications (p<0.0000). 105 patients (34.4%) had surgical complications overall which gave a similar relation between higher points and less complications (p<0.000).
Conclusions: In total 34.4% of the patients had complications and there was a clear relation between the quality of osteosynthesis and complications. The outcome of traditional TBW is therefore depending on the quality of the osteosynthesis.

102. Superior capsular reconstruction (SCR) – results after reconstruction with a porcine extracellular matrix graft.
Anton Ulstrup, Michael Reinhold, Otto Falster
Department of Orthopaedic Surgery, Holbæk Hospital; Department of Orthopaedic Surgery, Holbæk Hospital; Department of Orthopaedic Surgery, Holbæk Hospital

Background: A prerequisite for a satisfying functional result in the treatment of an irreparable rotator cuff rupture is a significant reduction of shoulder pain and better range of motion with an increase in anatomical glenohumeral joint stability.
Purpose / Aim of Study: Prospective study to examine the outcome after superior capsular reconstruction using a porcine extracellular matrix dermal graft.
Materials and Methods: Clinical results were evaluated using the Constant score and WORC index over a 2- year period. All patients had magnetic resonance imaging of the injured shoulder after one year.
Findings / Results: 13 patients with 13 superior capsular reconstructions were included over a 3-year period. Mean age was 61 years (range 50 to 70) at the time of surgery. At final follow-up (mean 24 months, range 23 to 26) the mean Constant score had improved by a percentage average of 127 % (0-268, % increase). The mean WORC index had increased by a percentage average of 130 % (0-484, % increase). 11 out of 13 grafts were intact on follow-up magnetic resonance imaging.
Conclusions: Our hypothesis was that successful implantation of a dermal xenograft would correlate with both better functional outcome and stabilized glenohumeral radiographical features. We saw a group of patients with variable but significant increases in functional results and in general with limited pain and satisfaction and intact xenografts on an MRI scan. We did not find a positive correlation between functional outcome scores and graft durability and with single cuff defects versus larger rotator cuff defects. The group of patients were generally qualitatively and measurably satisfied with their result. This study suggests that a superior capsular reconstruction can yield results that are comparable or superior to other known salvage treatment options in patients with large to massive rotator cuff defects without significant cuff tear arthropathy. The hypothesis that superior capsular reconstruction can be a relevant treatment method for irreparable rotator cuff tears could not be refuted despite a fairly low patient inclusion number. With these results, selected patients can be considered for a different treatment than reverse shoulder arthroplasty, debridement or tendon transfer.

103. Ultrasonographic measurements of subacromial structures in patients with subacromial pain show moderate to excellent interrater reliability when performed by novice sonographers
Karen Mikkelsen, Adam Witten, Birgitte Hougs Kjær, Per Hölmich, Kristoffer Weisskirchner Barfod
Sports Orthopedic Research Center - Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital Amager Hvidovre; Sports Orthopedic Research Center - Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital Amager Hvidovre; Dept. of Physical and Occupational Therapy, Institute of Sports Medicine Copenhagen (ISMC), Copenhagen University Hospital Bispebjerg Frederiksberg; Sports Orthopedic Research Center - Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital Amager Hvidovre; Sports Orthopedic Research Center - Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital Amager Hvidovre

Background: Ultrasonography is becoming increasingly available for health professionals with limited sonographic experience. In the diagnosis of shoulder problems ultrasonography is commonly used and has been described as a helpful and reliable tool, when performed by experienced sonographers. The reliability of subacromial measurements performed by novices is thus relevant.
Purpose / Aim of Study: To investigate if standardized ultrasonographic subacromial measurements are reliable in the hands of novice sonographers.
Materials and Methods: After an open training- and supervision phase, two novice sonographers, a medical student and an orthopedic resident, performed a standardized ultrasonographic protocol on patients diagnosed with subacromial pain by orthopedic specialists. The protocol consisted of two measures of supraspinatus tendon thickness and subacromial bursa thickness, one measure of acromio-humeral distance and an assessment of dynamic impingement. Intraclass correlation coefficients (ICC 2,2), linear weighted κ, standard error of the measurement (SEM), minimal detectable change (MDC) and linear weighted κ were used to evaluate reliability.
Findings / Results: Measurements were obtained from 28 symptomatic shoulders and 20 contralateral asymptomatic shoulders. ICC-values for supraspinatus tendon thickness ranged from 0.84 to 0.87 (SEM 0.43–0.50 mm, MDC 1.19–1.38 mm, mean (SD): 5.72 (0.9) mm). Subacromial bursa thickness had ICC ranging from 0.58 to 0.93 (SEM 0.15–0.35 mm, MDC 0.41- 0.97 mm, mean (SD): 1.70 (0.43) mm). For acromio- humeral distance ICC ranged from 0.81 to 0.84 (SEM 0.90-0.93 mm, MDC 2.50-2.57 mm, mean (SD): 11.59 (1.70) mm). Reliability of dynamic impingement was fair in symptomatic shoulders (κ: 0.29, agreement: 68 %) and moderate in asymptomatic shoulders (κ: 0.46, agreement: 90 %).
Conclusions: Although the results are inferior to results obtained by experienced sonographers, ultrasonographic assessment by novice sonographers showed acceptable reliability, with supraspinatus tendon thickness and acromio-humeral distance measures resulting in good reliability. Reliability of the bursa measurements ranging from moderate to excellent and the assessment of dynamic impingement resulting in fair to moderate reliability.

104. Rotator Cuff Tear; A diagnose often missed at initial contact. A prospective study
Chris Amdisen, Michael Toft Væsel, Marianne Toft Vestermark
Department of Orthopedics, Regionshospitalet Viborg; , ; Department of Orthopedics, Regionshospitalet Viborg

Background: Rotator cuff tears are common injuries. They are often missed upon the initial examination at the emergency room.
Purpose / Aim of Study: In this study, the incidence rate of rotator cuff tears in patients seen in the emergency room with relevant shoulder trauma is evaluated. Furthermore, it is investigated, whether a limited clinical examination is correlated to an ultrasonography confirmed rotator cuff tear.
Materials and Methods: Patients referred to the emergency room with isolated shoulder trauma and no x-ray verified fracture, were referred to a follow-up examination with a shoulder surgeon within 14 days after trauma. At follow-up a limited clinical examination with three diagnostic tests was performed. The patients were tested for: abduction, external rotation and impingement. The clinical examination was immediately followed by an ultrasonography examination to determine the status of the rotator cuff.
Findings / Results: We included 59 patients in the study with a median age of 47 years. 7 (12%) patients had a rotator cuff tear (RC tear) upon evaluation. If the patient was a candidate for surgery, the cuff tears would be verified by MRI or arthroscopy. 17 patients had all three tests positive at the follow- up examination. Of these, 7 (24%) patients, had a RC tear. All patients with a RC tear had a positive test for external rotation, and all three diagnostic tests had negative predictive values above 92%.
Conclusions: 12% of the patients seen in the emergency room after isolated shoulder trauma had a RC tear. This study shows that a limited clinical examination can assist the surgeon in determining which patients are likely to have a RC tear and for whom, a referral for a concluding ultrasonography examination is likely recommendable.