Session 14: Poster med foredrag A

Onsdag 21. oktober
11:00 – 12:00
Lokale: Reykjavik
Chairmen: Micheal Bentsen / Theis Thillemann

140. Preoperative treatment of Giant-Cell Tumors of Bone with Denosumab
Anna Lynge Sørensen, Rehne Lessmann Hansen, Inger Krog-Mikkelsen, Peter Holmberg Jørgensen
Orthopaedic Surgery Research, University Hospital of Aarhus; Orthopaedic Surgery, Tumor Section, University Hospital of Aarhus

Background: Giant cell tumor of bone(GCT) is a locally aggressive tumor classified as borderline malignant. GCT consists of multinucleated giant cells(osteoclast-like- cells) and stromal cells which lead to destruction of the bone. Treatment has so far been surgical resection. Denosumab(Dmab) is a RANKL-inhibitor which inhibits osteoclasts and impairs the growth of GCT
Purpose / Aim of Study: To describe the clinical, radiographic and pathological effects on the first 5 GCT-patients in Denmark treated with Dmab
Materials and Methods: 5 patients(15-30 years) with GCT considered operable only by amputation or with a high risk of functional impairment were treated preoperatively with Dmab, 120mgx1s.c. at day 1, 8 and 15 and every 4 week. Treatment was continued until the patients were considered operable (3-8 months) Patients were surgically treated with curettage and cement (3), bone graft (1) and wide resection (1). Tumor-size was evaluated on MRI and X-ray until surgical treatment. Local tumor bone mineral density(BMD) and bone turnover markers(osteocalcin and CTX) was followed in 3 patients. GCT was evaluated histologically before and after treatment with Dmab
Findings / Results: Dmab treatment resulted in reduction in tumor size in 3 patients. BMD increased by 37-44% and bone formation increased. The GCT tissue almost disappeared and was replaced by benign fibrous histiocytoma tissue. All patients experienced pain reduction after 5 weeks of treatment. No adverse events were reported. Two patients had a recurrence of which 1 was amputated and 1 had a wide resection of the tumor
Conclusions: Dmab has a deleterious effect on GCT tissue resulting in increased bone deposition. Recurrence may occur probably due to presence of stroma cells not affected by Dmab. It is questioned whether Dmab treatment should be continued after surgery in this selected group of patients

141. Danish Hip Arthroscopy Registry: The first outcome description of patients with femoroacetabular impingement (FAI).
Bent Lund, Bjarne Mygind-Klavsen, Torsten Grønbech Nielsen, Per Hölmich, Otto Kraemer, Martin Lind
Department of Orthopedics, Horsens Regional Hospital; Department of Sportstraumatology, Aarhus University Hospital; Arthroscopic Center, Department of Orthopedics , Copenhagen University Hospital, Amager-Hvidovre; Arthroscopic Center, Department of Orthopedics, Copenhagen University Hospital, Amager-Hvidovre

Background: The Danish Hip Arthroscopy Registry (DHAR) was initiated in January 2012 as a web-based prospective registry.
Purpose / Aim of Study: The purpose of this study was to evaluate and report the outcome data of a Danish population with radiological and clinical FAI undergoing hip arthroscopy. Our primary hypothesis was that patients undergoing hip arthroscopy would improve significantly in both pain, quality of life and in sports related outcome measurements in Patient Related Outcome Measures (PROM).
Materials and Methods: Perioperative data and PROM data from DHAR between January 2012 and May 2015 was extracted. Radiological pincer- type FAI was defined as LCE > 35 degrees and CAM-type FAI as Alfa angle > 55 degrees. These data was combined with FAI surgical data such as osteoplasty and labral repair or resection. PROMs consisting of iHOT12, HAGOS, EQ-5D and VAS pain scores were submitted online by the patients preoperatively and at 1, 2 and 5 years follow-up.
Findings / Results: We extracted data from 1480 FAI patients in DHAR. HAGOS demonstrated significant improvement in all subscales at follow up. EQ-5D demonstrated improvement after 1 and 2 years from 0,66 pre-op to 0,78 at 2 years. Mean iHOT12 was respectively 47 (pre-op), 49 (1 year FU) and 43 (2 year FU). At 1 year follow up iHOT12 shows improvement in 5 subscales, deteriorating in 3 subscales and no change in 4 subscales. At 2 year follow up there was a worsening in 6 subscales including pain in hip, getting up from floor, sexual activity, carrying children, walking distances, pushing and lifting. The pain score data demonstrated improvement in VAS 55 to 33 at follow up.
Conclusions: We conclude that patients with femoroacetabular impingement undergoing hip arthroscopy experience improvement in pain and quality of life but only in some aspects of function and sports.

142. Danish Hip Arthroscopy Registry: An epidemiologic and perioperative description of the first two thousand patients.
Bjarne Mygind-Klavsen, Torsten Grønbech Nielsen, Otto Kraemer, Per Hölmich, Bent Lund, Martin Lind
Department of Sportstraumatology, Aarhus University Hospital; Arthroscopic Center, Department of Orthopedics , Copenhagen University Hospital, Amager-Hvidovre; Department of Orthopedics, Horsens Regional Hospital

Background: The Danish Hip Arthroscopy Registry (DHAR) was initiated in January 2012 as a web-based prospective registry.
Purpose / Aim of Study: The purpose of this study was to evaluate and report the epidemiologic and perioperative data of the first two thousand patients in the DHAR and to describe the registry. We hypothesized that patients undergoing hip arthroscopy have considerable hip and/or groin pain, loss of function and reduced quality of life measured and that the majority of patients were treated for femoroacetabular impingement (FAI).
Materials and Methods: Surgeons report operative and radiographic data on-line to the database. Patients submit on-line preoperatively and at follow- up several patient reported outcome measures (PROM). These PROMs are all validated scores suitable for Danish patients undergoing hip arthroscopy. Perioperative data and PROM data from the DHAR between January 2012 and May 2015 was extracted.
Findings / Results: The 2000 patients consisted of 56% females and 44% males. Mean age 37,5 years. Mean surgical time was 86 minutes and mean traction time 49.7 minutes. The most frequent procedure was CAM and Pincer resection in 86% and labral refixation in 70% of the cases. Acetabular chondral damage Grade III and IV changes were seen in 41 % of the cases. The preoperative iHOT12 PROM was mean 45 based on all 12 items. EQ-5D was 0.65 and HAGOS sub scores were 51 (pain), 49 (symptoms), (ADL), 35 (sport), 20 (physical activity) and 29 (QoL) respectively.
Conclusions: We conclude that patients undergoing hip arthroscopy report considerable pain, loss of function, reduced activity level and reduced quality of life prior to surgery. The majority of patients undergo procedures for FAI treatment. We consider the development of a national clinical registry for hip arthroscopy successful as both a clinical and scientific tool.

143. Healthy patients with colonized implants - a ticking bomb for the future of orthopedics?
Charlotte Stenqvist, Steffen Eickhardt, Thomas Bjarnsholt, Jesper Hvolris
Department of Orthopedic Surgery , Bispebjerg Hospital; Department of Immunology & Microbiology , University of Copenhagen; Department of Orthopedic Surgery, Bispebjerg Hospital

Background: Many chronic infections are caused by aggregates of bacteria called biofilm. The biofilms are small, heterogeneously spread within the infected area and have a low metabolism. Because of this, the bacteria are hard to eradicate with standard antibiotic treatment, but they are also hard to diagnose. Not much is known about the early stages of infection.
Purpose / Aim of Study: The purpose of this study was to identify and describe whether healthy implants are colonized with microbiological agents.
Materials and Methods: Over a two-month period 20 implants were collected from adult patients, using a standard aseptic surgical procedure. Inclusion criteria were no clinical sign of infection. Implants were placed into sterile containers with physiological saline adequate for sonication. Implants were vortexed and sonicated followed by centrifugation. The pellet was re- suspended, plated on agar-plates and DNA was purified. Colonies were analysed by MALDI-TOF (Matrix Assisted Laser Desorption/Ionization - Time of Flight Mass Spectrometry), DNA was analysed with RT- PCR and sequenced to identify bacterial and fungal agents.
Findings / Results: The median time for an implant in our 20 patients was 10 months with a range from 0.3-432 months. 14 patients had implants removed after fracture surgery; five implants came from arthroplasty surgery and one from ligament reconstruction. We found 12 positive at agar-plates and MALDI-TOF. PCR found 8 positive for bacterial agents and 6 for fungal agents. Only one set of seven Kamme-Lindberg cultures were found to be positive.
Conclusions: Clinically non-infected implants may be colonized by bacterial and fungal agents. This study indicates that bacteria can prosper on implants without causing pathology. Further research should examine a greater cohort of patients.

144. Patient reported effect of arthroscopic subacromial decompression after failure of conservative treatment.
Jón Rói Jacobsen, Søren Rasmussen Deutch, Carsten Moss Jensen
Departement of Orthopedics ( Århus universitet), Randers Regionshospital; Departement of Orthopedics, Randers Regionshospital

Background: Impingement of the shoulder is the most common shoulder complaint. Though previously investigated, an international consensus in treatment of impingement is inconclusive. Several studies have provided good evidence of the effects of an Arthroscopic Subacromial Decompression(ASD), but recent studies have cast doubt if surgery is beneficial in treating impingement. However, few studies have investigated which patients would benefit the most from an ASD, after conservative treatment has failed.
Purpose / Aim of Study: To decide the effect of ASD in patients suffering from impingement after conservative treatment has failed. Furthermore, an investigation of which patients benefit the most from ASD.
Materials and Methods: 235 patients with no limitations of age were prospectively included in the study. All patients were treated with an ASD at the department of Orthopedics at Randers Regionshospital, Denmark. Patients submitted two questionnaires before surgery and at 6 months follow-up. The questionnaires included The Oxford Shoulder Score (OSS), EQ-5D and VAS of arm function.
Findings / Results: Patients were divided into 3 subgroups according to low/moderate/high Pre-OSS. The Low Pre-OSS group had a mean difference in OSS of 18.8 [12.9 ; 24.7]p=0.0001. The Moderate Pre-OSS group had a mean difference in OSS of 11.9 [6.6 ; 17.3]p=0.0001 The high Pre-OSS had a mean difference in OSS of 4.1 [-1 ; 9.3]p=0.11. The EQ-5D and VAS of arm function also concluded a significant shift in the low/moderate Pre-OSS group, and also pointed out that quality of life was compatible for all groups postoperatively.
Conclusions: ASD is an effective treatment for patients suffering from impingement after conservative treatment has failed. Furthermore our study provides evidence that patients with lower/moderate Pre-OSS benefit the most from surgical intervention.

145. Does an accelerated hip fracture pathway in a non-orthogeriatric unit reduce hospitalization without changes in 30 day mortality?
Martin Peter Nielsen, Jon Jacobsen, Peter Revald
Orthopedic Surgery, Randers Regional Hospital

Background: Hip fractures pose a socio-economical challenge and often result in long-term hospitalization. This is hazardous for weakened elderly patients who risk infections, deterioration and thereby increased mortality. Accelerated hip fracture pathways in orthogeriatric units have shown to have a positive effect on hospital Length Of Stay and mortality.
Purpose / Aim of Study: To evaluate if implementation of an accelerated hip fracture pathway in a non-orthogeriatic unit reduces LOS while not increasing mortality or readmission rates.
Materials and Methods: A multidisciplinary hip fracture study-group involving doctors, other health professionals and the community care was created. An optimized accelerated hip fracture program was designed. Early contact to community care, early surgery, mobilization and accelerated rehabilitation after discharge was intended. The program was enrolled on the 1/9/2014. A consecutive group of patients with ICD (S72.0/1/2) proximal femoral fracture admitted through the Emergency Department from the 1/9/2014 to 31/12/2014 was compared with a consecutive group of patients admitted 1/9/2011 to 31/12/2011 with the same ICD codes.
Findings / Results: Demographic data, ASA-score and fracture types were comparable. LOS decreased significantly from a mean at 133 hours (5.5 days) 95%CI [124;142] to 97 hours (4.0 days) [89;107], p < 0.0001. Thirty-day mortality of 9 % was seen in both cohorts which compares to that of similar studies. The readmission rate did not change significantly. Data showed an unforeseen increase in proximal femoral fractures of 36,2% admitted to the hospital in the observation period from 2011 to 2014.
Conclusions: Implementation of an accelerated hip fracture pathway in a non-orthogeriatric unit decreased LOS without increasing mortality or readmission.

146. Comparison of Clinical Results with Bone Allograft or PMMA after Intralesional Curettage for Giant Cell Tumors of Bone
Peter Frederik Horstmann, Peter Holmberg Jørgensen, Werner Hettwer, Bjarne Hauge Hansen, Michael Mørk Petersen
Muskuloskeletal Tumor Section, Copenhagen University Hospital; ) Department of Orthopedic Surgery, Sarcoma Center , University Hospital of Aarhus

Background: PMMA is a popular option for reconstruction after curettage of giant cell tumors (GCT). However, bone remodeling is precluded by the presence of PMMA, which is why cancellous allograft remains the preferred material for bone defect reconstruction in some centers. Wide resection is usually only considered when the joint is deemed unsalvageable.
Purpose / Aim of Study: To determine local recurrence rates after wide resection of GCT compared to intralesional treatment.
Materials and Methods: A retrospective review of all consecutive patients (n=104, M/F: 60/44, mean age 35 (11-84 years) treated for GCT in the appendicular skeleton at two orthopedic oncology centers between 1998 and 2013. Choice of treatment and local recurrence rates was recorded and evaluated with statistical methods including Kaplan-Meier survival analysis and log rank test.
Findings / Results: Wide resection (16 arthroplasties, 15 local bone resections and 4 amputations) was performed in 35 patients. The remaining 69 patients underwent curettage and bone defect reconstruction with cancellous allograft (n=37) or PMMA (n=32). Local recurrence occurred in only 1 case of patients treated with wide resection, whereas it occurred in 23 cases of patients treated by intralesional curettage. This difference between wide and intralesional treatment was statistically highly significant (P<0,001). When comparing local recurrence rates of reconstruction methods for intralesional treatment, we found no statistical difference (p=0.75) between bone cement (n=10) and bone graft (n=13).
Conclusions: Wide resection of GCT’s is associated with very low recurrence rates compared to intralesional treatment. We were unable to detect a statistical difference in recurrence rates when using PMMA for bone defect reconstruction compared to bone allograft without further adjuvant therapy.

147. Clinical Results after Intralesional Curettage in Benign and Borderline Bone Tumors
Peter Frederik Horstmann, Werner Hettwer, Michael Mørk Petersen
Muskuloskeletal Tumor Section, Copenhagen University Hospital

Background: Intralesional curettage is a common surgical treatment for benign bone tumors. Although, in principle, the tumor recurrence rate is higher with intralesional surgery, the functional outcome is often better than in wide resections.
Purpose / Aim of Study: To determine the clinical results following curettage and bone grafting.
Materials and Methods: We performed a retrospective review of all consecutive patients (n=166, F/M: 86/80, mean age 31 (2-72 years)) who underwent intralesional curettage for benign or borderline bone tumors in the appendicular skeleton at our orthopedic oncology center, between 2009 and 2013. We recorded histology and anatomic region of the bone tumors, choice of treatment and biopsy verified local recurrence rates.
Findings / Results: The most common lesions treated were enchondromas (n=57), simple cysts (n=31), aneurysmal bone cysts (n=16), fibrous dysplasia (n=14) and GCT’s (n=13). Cancellous allograft was used for bone defect reconstruction in the majority of the cases (n=141). Autograft was used in 3 cases and a bone graft substitute in 5 cases. In 17 cases, the bone defect was left empty. The most commonly affected long bones were femur (n=47), tibia (n=26) and humerus (n=10), and the most commonly affected region was the knee (n=47). We recorded 10 complications, with postoperative infection (n=3), postoperative fracture (n=2) and nerve palsy (n=2) being the most common. Local recurrence occurred in 13 cases (8%), with simple cysts in children (n=3) surprisingly being the most common.
Conclusions: In this 5-year review of 166 patients, treated for a benign or borderline bone tumor in a single orthopedic oncology center, we found that intralesional curettage and bone defect reconstruction with cancelleous bone allograft is a reliable treatment with acceptable recurrence and complication rates.

148. Reoperation factors in malleolus fracture surgery
Peter Sass Jensen
Department of Orthopedic Surgery, Odense University Hospital, Odense Denmark

Background: Malleolus fractures often require operation. They have a high reoperation rate – the second highest in Denmark only surpassed by proximal femoral fractures. Reoperation is followed by longer rehabilitation time and is uneconomical.
Purpose / Aim of Study: The reason for the high reoperation rate has yet to be determined. The purpose of the study was to provide a descriptive analysis of malleolus fracture operation cases that were followed by reoperation and to determine factors in primary operations that led to increases in reoperations.
Materials and Methods: This study included patients with operations registered in the Danish Fracture Database (DFDB) from November 2008 to May 2014 who were reoperated. The factors leading to reoperation were found.
Findings / Results: 111 of 281 reoperations had a primary operation registered in the DFDB: 43 underwent hardware removal due to irritation or pain from material; 26, postoperative infection; 22, suboptimal osteosynthesis, and 13, osteosynthesis failure. A resident or intern performed 79 of the 111 primary operations; 25 of the 111 were supervised by an attending surgeon or traumatologist AO fracture classification 44C was higher in reoperated patients with suboptimal osteosynthesis and osteosynthesis failure than in any primary operations.
Conclusions: Operations by unsupervised residents tended to have a higher reoperation rate than attending surgeons or supervised residents. More complex malleolus fractures seem to have a higher risk of suboptimal osteosynthesis or failure.

149. Bone shortening of clavicular fractures: comparison of measurement methods.
Anders Thorsmark Høj, Peter Udby, Ilija Ban, Lars Henrik Frich
orthopedic and traumatologic Holbæk, Odense university hospital research unit/ Holbæk sygehus; Orthopedic and traumatologic Køge, Køge; orthopedic and traumatologicHvidovre, Hvidovre; orthopedic and traumatologicOdense, Odense university hospital

Background: A relative indication for operative treatment of the fresh clavicular fracture is bone shortening over 2 cm; nonetheless this is controversial within the scandinavian countries were such a connection has not been found. A review of the literature shows different measurement methods for shortening are used scientifically.
Purpose / Aim of Study: We wanted to investigate if the scientifically used measurement methods were interchangeable to each other by comparing intraclass correlation, standard error of measurement and minimal detectable change as well as using Bland-Altman plots.
Materials and Methods: Two raters measured clavicle shortening on 65 patients using conventional radiographs on two separate sessions. The two methods described by Hill et al and Silva et al were used on unilateral pictures. Side comparison were done on panoramic radiographs.
Findings / Results: We found that none of the methods were directly interchangeable. We found fewer patients patients with bone shortening over 2 cm when using side comparison.
Conclusions: Our results cautions for the interpretation of scientific results on clavicular bone shortening. In a clinical context the measurement method used for clavicular bone shortening could be an explanatory factor in differences of operative care rates between countries.

150. Positiv cultures in primary cuff surgery
Thomas Falstie-Jensen, Theis Thillemann, Brian Elmengaard, Hans Viggo S. Johannesen, Janne Ovesen
orthopedic, Aarhus University Hospital; Orthopedic, Aarhus University Hospital

Background: High rate of positive tissue cultures are reported from primary shoulder arthroplasty but it is unclear whether open cuff surgery have similar rates.
Purpose / Aim of Study: To characterize and investigate the rates of positive cultures in patients undergoing open shoulder surgery
Materials and Methods: The study was designed as a prospective cohort study enrolling consecutive patients scheduled for open shoulder surgery between May 2014 and May 2015. Previously ipsilateral shoulder-operated patients were excluded. During surgery five tissue biopsies were obtained ad modum Kamme Lindberg and cultured for aerob and anaerob growth on three different plates, and in Serum broth and Semi-solid agar. All cultures were checked daily the first four days to identify growth. Serum broth and Semi-solid agar was furthermore observed after 14 days. Infection was defined as three or more positive cultures with the same bacteria and contamination as less than three. Results are presented with counts or percentage including 95% confidence interval (95% CI).
Findings / Results: Until February, 2015, 39 cases were included with an average age of 67 years (range: 47-79) and 15 were male (38.46%). Preliminary results showed seven infected cases 17.95% (95%CI 5.35-30.55) and two cases as contaminated (7.69%). All infected cases were proprionibacterium acne, all diagnosed after the extended growth period. The cases showed no clinical signs of infection postoperatively, although they later were diagnosed as infected or contaminated.
Conclusions: High rate of positive biopsies were found in assumable sterile shoulders. The clinical implication is unclear and raises the question of the need for prolonged prophylactic treatment after open shoulder surgery.