Clinical Note
Results of 10-year follow-up of the iliac donor site of graft patients
Journal of International Medical Research 2014, Vol. 42(6) 1348–1352 ! The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0300060514550351 imr.sagepub.com
Liqing Qi1,2,*, Yueju Liu1,2,*, Han Li1,2 and Yingze Zhang1,2
Abstract Objectives: To measure levels of pain and iliac regeneration at the iliac crest donor site during a 10-year follow-up of graft patients. Methods: This prospective study used a visual analogue scale (VAS) to assess pain at the donor site at 1 month and 1, 3, 5 and 10 years postoperatively. Iliac regeneration status was recorded at 1, 3, 5, 7 and 10 years postoperatively by comparing plain radiographs. Results: A total of 32 patients participated in the study. Mean VAS scores at 1 month, 1 year, 3, 5, and 10 years were 3.22, 3.39, 3.45, 2.02 and 1.38, respectively. There was no statistically significant difference between pain scores at 1 month and 1 year, but pairwise comparisons revealed significant differences between the other timepoints. The mean iliac regeneration rank scores at 1, 3, 5, 7 and 10 years were 1.36, 2.22, 2.97, 3.75 and 4.70, respectively; all pairwise comparisons were statistically significant. Conclusion: The iliac donor site showed a declining trend in pain, which appeared to have started 3 years postoperatively. Long-term follow-up showed that the ilium is readily able to repair itself.
Keywords Bone graft, iliac crest, regeneration Date received: 21 March 2014; accepted: 15 August 2014
Introduction Iliac graft harvesting is associated with considerable postoperative pain and discomfort.1 The pain at the donor site may persist and represents a significant source of postoperative morbidity. The incidence of relevant pain after bone-graft harvesting from the iliac crest at 3 months, 6 months and 2 years is reportedly 29%, 38% and 19%, respectively.2,3 However, long-term
1
Department of Orthopaedics, Third Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China 2 Key Orthopaedic Biomechanics Laboratory of Hebei Province, Shijiazhuang, Hebei Province, China *These authors contributed equally to this paper. Corresponding author: Dr Yingze Zhang, Department of Orthopaedics, Third Hospital of Hebei Medical University, 139 Zi Qiang Road, Shijiazhuang, Hebei 050051, China. Email: [email protected]
Creative Commons CC-BY-NC: This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 3.0 License (http://www.creativecommons.org/licenses/by-nc/3.0/) which permits non-commercial use, reproduction and distribution of the work without furtherDownloaded permissionfrom provided the original work is attributed the SAGE and Open Access page imr.sagepub.com at Uniwersytet Warszawskias onspecified March 20,on 2015 (http://www.uk.sagepub.com/aboutus/openaccess.htm).
Qi et al.
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follow-up of the donor site has not extended to 10 years. The aim of the present study was to describe the results of a 10-year follow-up of the status of the iliac donor site, particularly with respect to pain and bone regeneration.
Patients and methods Study population Adult patients scheduled to undergo internal fixation for various fractures using autogenous bone grafts were sequentially enrolled in this prospective study at the Department of Orthopaedics, Third Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China between January 2000 and December 2002. Patients with an American Society of Anesthesiologists (ASA) physical status of 1 or 2, aged between 30 and 40 years, were eligible for participation. Patients with multiple fractures, or fractures that required a secondary operation for non-union, were excluded from this study. Smokers were also excluded from the study. Institutional ethics committee approval was obtained from the Third Hospital of Hebei Medical University. Written informed consent was obtained from all patients.
Iliac crest bone harvesting An autograft was harvested from the anterior iliac crest in all patients. An incision of nearly 7 cm in length was made just below the anterior iliac wing, parallel to the iliac crest and centred over the iliac tubercle. Next, the skin was retracted to identify the iliac crest, and a scalpel was used to create an incision down onto the crest by stripping off the muscle from either the inner or outer wall of the ilium. Following the contour of the bone, a sharp dissection was carefully made to avoid straying out of the plane and into the soft tissue. The dissection was extended around the corner of the crest
onto the ilium using a Cobb elevator to obtain a complete 3 2 cm block of the ilium. Dissection was very carefully performed to avoid retraction of the inguinal ligament and a resultant inguinal hernia. The wound was irrigated with antibiotics and saline, and soft tissue haemostasis was achieved with bipolar cautery. The wound was closed, and internal fixation of the corresponding parts of the fracture was performed. One dose of cefuroxime (2.0 g) was given by intravenous administration preoperatively, followed by two additional doses during the first 24 h postoperatively.
Assessment of iliac pain and iliac bone regeneration Patients self-reported their pain using a visual analogue scale (VAS; 0, no pain; 10, worst pain imaginable) at 1 month and 1, 3, 5 and 10 years postoperatively. Plain radiographs of the hip graft site were obtained preoperatively and at 1, 3, 5, 7 and 10 years postoperatively, and the status of iliac regeneration was determined by two senior orthopaedic trauma physicians (L.Q. and Y.Z.). The status of iliac regeneration was divided into four levels, based on the comparison with plain preoperative radiographs. At level I, the amount of new bone volume was 50% to 70% of its original volume; at level IV, the amount of new bone volume was >70% of the original bone volume. The levels of iliac regeneration (I–IV) were given the rank scores of 1, 2, 3 and 4, respectively.
Statistical analyses All statistical analyses were performed using the SPSSÕ statistical package,
Downloaded from imr.sagepub.com at Uniwersytet Warszawski on March 20, 2015
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Journal of International Medical Research 42(6)
version 13.0 (SPSS Inc., Chicago, IL, USA) for WindowsÕ . The Friedman test and Wilcoxon signedrank test were used to generate mean rank scores. A P-value of 70% of the original bone volume (level IV iliac regeneration; Table 1). Results of the VAS scoring for pain at the donor site are shown in Table 2. The mean VAS scores at 1 month and 1, 3, 5 and 10 years were 3.22, 3.39, 3.45, 2.02 and 1.38,
Table 1. Status of postoperative bone regeneration at the iliac crest bone graft donor site, as determined by two senior orthopaedic trauma physicians, based on comparison with plain preoperative radiographs, in patients (n ¼ 32) who underwent iliac crest bone graft harvesting. Postoperative time, years Bone regeneration levela 1 3 5 7 10 I II III IV Mean rank scoreb,c
32 0 0 0 1.36
13 19 0 0 2.22
7 16 9 0 2.97
3 12 15 2 3.75
0 4 21 7 4.70
Data presented as n of patients unless otherwise stated. a Status of iliac regeneration was divided into four levels: level I, amount of new bone volume 50% to 70% of its original volume; level IV, amount of new bone volume was >70% of original bone volume. b Levels of iliac regeneration (I–IV) were given mean rank scores of 1, 2, 3 and 4, respectively. c P < 0.001 for all postoperative comparisons; Friedman test and Wilcoxon signed-rank test.
respectively. Pairwise comparison using Wilcoxon signed-rank test (a0 ¼ 0.005) showed no statistically significant difference between 1 month and 1 year. However, there were statistically significant differences between the other pairwise comparisons (P < 0.05 for all comparisons).
Discussion Iliac crest autografting is considered to be the gold standard grafting technique in fracture internal fixation procedures and in some spinal fusion surgeries.1 Harvesting of the iliac crest graft is associated with morbidity, particularly persistent pain at the graft harvest site, in up to one-third of patients.4,5 However, the most recent studies have reported incidences of relevant pain with a follow-up of 3 years.5
Downloaded from imr.sagepub.com at Uniwersytet Warszawski on March 20, 2015
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Table 2. Extent of postoperative pain at the bone graft donor site, scored using a visual analogue scale (VAS) in patients (n ¼ 32) who underwent iliac crest bone graft harvesting. Postoperative time VAS scorea 1 month 1 year 3 years 5 years 10 years 0 1 2 3 4 5 6 7 8 9 10 Mean VAS score
5 5 5 5 3 1 1 2 1 3 1 3.22
5 4 3 9 2 2 0 0 2 3 2 3.39
5 6 7 4 2 1 2 4 1 0 0 3.45b
11 19 6 7 8 2 4 3 2 0 0 0 0 1 1 0 0 0 0 0 0 0 2.02b 1.38b
Data presented as n of patients unless otherwise stated. a VAS scores; 0, no pain; 10, worst pain imaginable. b Statistically significant differences between pairwise comparisons (P < 0.05 for all comparisons; Wilcoxon signed-rank test).
The present study is is the first prospective study to examine pain and bone regeneration with a follow-up of 10 years. In this study, we found that pain was significantly lower 3 years postoperatively compared with 1 year postoperatively. This reduction in pain was primarily exhibited because fewer patients reported severe pain as the postoperative time increased. This result may affect the number of orthopaedic surgeons who propose reconstruction of the iliac crest to reduce pain. Several methods to reduce graft site pain are currently available. For example, Tanishima et al.6 recommended rounding off the graft harvest site edges. Reconstruction of the graft site with resorbable mesh has been shown to reduce early postoperative pain.7 Continuous application
of 0.2% ropivacaine through an iliac crest catheter with iliac crest bone grafting was demonstrated to be an effective method for pain relief for the first 48 h, and the benefit of this technique was still present after 3 months.8 However, most of these were retrospective studies with shorter follow-up times, which seriously affected their credibility. This present study revealed a declining trend in pain, which appeared to have started 3 years postoperatively, suggesting that pain relief does not require ilium reconstruction. This present study also observed the phenomenon of bone regeneration. The results demonstrated that the ilium exhibited a good ability to repair itself in the long term. This was perhaps related to the choice of patients, who were younger people (aged 30–40 years) with fractures and no medical comorbidities (ASA physical status of 1 or 2). This present study selected younger rather than older patients with spinal diseases to ensure successful completion of a 10year follow-up; thus, the extent of iliac regeneration may have been exaggerated in this study. This present study sought to determine whether bone regrowth at the harvest site was associated with pain relief, but it was unable to determine this because the sample size was too small. This problem requires further investigation in a multicentre prospective study with a larger sample size. In conclusion, this present study demonstrated that the iliac crest bone graft donor site showed a declining trend in pain over the follow-up period, which may have started at 3 years postoperatively. Analysis of plain radiographs demonstrated that the ilium was readily able to repair itself over the long term. Declaration of conflicting interest The authors declare that there are no conflicts of interest.
Downloaded from imr.sagepub.com at Uniwersytet Warszawski on March 20, 2015
1352
Journal of International Medical Research 42(6)
Funding This research received no specific grant from any funding agency in the public, commercial, or notfor-profit sectors.
5.
References 1. Almaiman M, Al-Bargi HH and Manson P. Complication of anterior iliac bone graft harvesting in 372 adult patients from May 2006 to May 2011 and a literature review. Craniomaxillofac Trauma Reconstr 2013; 6: 257–266. 2. Fasolis M, Boffano P and Ramieri G. Morbidity associated with anterior iliac crest bone graft. Oral Surg Oral Med Oral Pathol Oral Radiol 2012; 114: 586–591. 3. Loeffler BJ, Kellam JF, Sims SH, et al. Prospective observational study of donor-site morbidity following anterior iliac crest bonegrafting in orthopaedic trauma reconstruction patients. J Bone Joint Surg Am 2012; 94: 1649–1654. 4. Ropars M, Zadem A, Morandi X, et al. How can we optimize anterior iliac crest bone
6.
7.
8.
harvesting? An anatomical and radiological study. Eur Spine J 2014; 23: 1150–1155. Skeppholm M and Olerud C. Pain from donor site after anterior cervical fusion with bone graft: a prospective randomized study with 12 months of follow-up. Eur Spine J 2013; 22: 142–147. Tanishima T, Yoshimasu N and Ogai M. A technique for prevention of donor site pain associated with harvesting iliac bone grafts. Surg Neurol 1995; 44: 131–132. Wang MY, Levi AD, Shah S, et al. Polylactic acid mesh reconstruction of the anterior iliac crest after bone harvesting reduces early postoperative pain after anterior cervical fusion surgery. Neurosurgery 2002; 51: 413–416. Blumenthal S, Dullenkopf A, Rentsch K, et al. Continuous infusion of ropivacaine for pain relief after iliac crest bone grafting for shoulder surgery. Anesthesiology 2005; 102: 392–397.
Downloaded from imr.sagepub.com at Uniwersytet Warszawski on March 20, 2015
Results of 10-year follow-up of the iliac donor site of graft patients
Journal of International Medical Research 2014, Vol. 42(6) 1348–1352 ! The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0300060514550351 imr.sagepub.com
Liqing Qi1,2,*, Yueju Liu1,2,*, Han Li1,2 and Yingze Zhang1,2
Abstract Objectives: To measure levels of pain and iliac regeneration at the iliac crest donor site during a 10-year follow-up of graft patients. Methods: This prospective study used a visual analogue scale (VAS) to assess pain at the donor site at 1 month and 1, 3, 5 and 10 years postoperatively. Iliac regeneration status was recorded at 1, 3, 5, 7 and 10 years postoperatively by comparing plain radiographs. Results: A total of 32 patients participated in the study. Mean VAS scores at 1 month, 1 year, 3, 5, and 10 years were 3.22, 3.39, 3.45, 2.02 and 1.38, respectively. There was no statistically significant difference between pain scores at 1 month and 1 year, but pairwise comparisons revealed significant differences between the other timepoints. The mean iliac regeneration rank scores at 1, 3, 5, 7 and 10 years were 1.36, 2.22, 2.97, 3.75 and 4.70, respectively; all pairwise comparisons were statistically significant. Conclusion: The iliac donor site showed a declining trend in pain, which appeared to have started 3 years postoperatively. Long-term follow-up showed that the ilium is readily able to repair itself.
Keywords Bone graft, iliac crest, regeneration Date received: 21 March 2014; accepted: 15 August 2014
Introduction Iliac graft harvesting is associated with considerable postoperative pain and discomfort.1 The pain at the donor site may persist and represents a significant source of postoperative morbidity. The incidence of relevant pain after bone-graft harvesting from the iliac crest at 3 months, 6 months and 2 years is reportedly 29%, 38% and 19%, respectively.2,3 However, long-term
1
Department of Orthopaedics, Third Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China 2 Key Orthopaedic Biomechanics Laboratory of Hebei Province, Shijiazhuang, Hebei Province, China *These authors contributed equally to this paper. Corresponding author: Dr Yingze Zhang, Department of Orthopaedics, Third Hospital of Hebei Medical University, 139 Zi Qiang Road, Shijiazhuang, Hebei 050051, China. Email: [email protected]
Creative Commons CC-BY-NC: This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 3.0 License (http://www.creativecommons.org/licenses/by-nc/3.0/) which permits non-commercial use, reproduction and distribution of the work without furtherDownloaded permissionfrom provided the original work is attributed the SAGE and Open Access page imr.sagepub.com at Uniwersytet Warszawskias onspecified March 20,on 2015 (http://www.uk.sagepub.com/aboutus/openaccess.htm).
Qi et al.
1349
follow-up of the donor site has not extended to 10 years. The aim of the present study was to describe the results of a 10-year follow-up of the status of the iliac donor site, particularly with respect to pain and bone regeneration.
Patients and methods Study population Adult patients scheduled to undergo internal fixation for various fractures using autogenous bone grafts were sequentially enrolled in this prospective study at the Department of Orthopaedics, Third Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China between January 2000 and December 2002. Patients with an American Society of Anesthesiologists (ASA) physical status of 1 or 2, aged between 30 and 40 years, were eligible for participation. Patients with multiple fractures, or fractures that required a secondary operation for non-union, were excluded from this study. Smokers were also excluded from the study. Institutional ethics committee approval was obtained from the Third Hospital of Hebei Medical University. Written informed consent was obtained from all patients.
Iliac crest bone harvesting An autograft was harvested from the anterior iliac crest in all patients. An incision of nearly 7 cm in length was made just below the anterior iliac wing, parallel to the iliac crest and centred over the iliac tubercle. Next, the skin was retracted to identify the iliac crest, and a scalpel was used to create an incision down onto the crest by stripping off the muscle from either the inner or outer wall of the ilium. Following the contour of the bone, a sharp dissection was carefully made to avoid straying out of the plane and into the soft tissue. The dissection was extended around the corner of the crest
onto the ilium using a Cobb elevator to obtain a complete 3 2 cm block of the ilium. Dissection was very carefully performed to avoid retraction of the inguinal ligament and a resultant inguinal hernia. The wound was irrigated with antibiotics and saline, and soft tissue haemostasis was achieved with bipolar cautery. The wound was closed, and internal fixation of the corresponding parts of the fracture was performed. One dose of cefuroxime (2.0 g) was given by intravenous administration preoperatively, followed by two additional doses during the first 24 h postoperatively.
Assessment of iliac pain and iliac bone regeneration Patients self-reported their pain using a visual analogue scale (VAS; 0, no pain; 10, worst pain imaginable) at 1 month and 1, 3, 5 and 10 years postoperatively. Plain radiographs of the hip graft site were obtained preoperatively and at 1, 3, 5, 7 and 10 years postoperatively, and the status of iliac regeneration was determined by two senior orthopaedic trauma physicians (L.Q. and Y.Z.). The status of iliac regeneration was divided into four levels, based on the comparison with plain preoperative radiographs. At level I, the amount of new bone volume was 50% to 70% of its original volume; at level IV, the amount of new bone volume was >70% of the original bone volume. The levels of iliac regeneration (I–IV) were given the rank scores of 1, 2, 3 and 4, respectively.
Statistical analyses All statistical analyses were performed using the SPSSÕ statistical package,
Downloaded from imr.sagepub.com at Uniwersytet Warszawski on March 20, 2015
1350
Journal of International Medical Research 42(6)
version 13.0 (SPSS Inc., Chicago, IL, USA) for WindowsÕ . The Friedman test and Wilcoxon signedrank test were used to generate mean rank scores. A P-value of 70% of the original bone volume (level IV iliac regeneration; Table 1). Results of the VAS scoring for pain at the donor site are shown in Table 2. The mean VAS scores at 1 month and 1, 3, 5 and 10 years were 3.22, 3.39, 3.45, 2.02 and 1.38,
Table 1. Status of postoperative bone regeneration at the iliac crest bone graft donor site, as determined by two senior orthopaedic trauma physicians, based on comparison with plain preoperative radiographs, in patients (n ¼ 32) who underwent iliac crest bone graft harvesting. Postoperative time, years Bone regeneration levela 1 3 5 7 10 I II III IV Mean rank scoreb,c
32 0 0 0 1.36
13 19 0 0 2.22
7 16 9 0 2.97
3 12 15 2 3.75
0 4 21 7 4.70
Data presented as n of patients unless otherwise stated. a Status of iliac regeneration was divided into four levels: level I, amount of new bone volume 50% to 70% of its original volume; level IV, amount of new bone volume was >70% of original bone volume. b Levels of iliac regeneration (I–IV) were given mean rank scores of 1, 2, 3 and 4, respectively. c P < 0.001 for all postoperative comparisons; Friedman test and Wilcoxon signed-rank test.
respectively. Pairwise comparison using Wilcoxon signed-rank test (a0 ¼ 0.005) showed no statistically significant difference between 1 month and 1 year. However, there were statistically significant differences between the other pairwise comparisons (P < 0.05 for all comparisons).
Discussion Iliac crest autografting is considered to be the gold standard grafting technique in fracture internal fixation procedures and in some spinal fusion surgeries.1 Harvesting of the iliac crest graft is associated with morbidity, particularly persistent pain at the graft harvest site, in up to one-third of patients.4,5 However, the most recent studies have reported incidences of relevant pain with a follow-up of 3 years.5
Downloaded from imr.sagepub.com at Uniwersytet Warszawski on March 20, 2015
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Table 2. Extent of postoperative pain at the bone graft donor site, scored using a visual analogue scale (VAS) in patients (n ¼ 32) who underwent iliac crest bone graft harvesting. Postoperative time VAS scorea 1 month 1 year 3 years 5 years 10 years 0 1 2 3 4 5 6 7 8 9 10 Mean VAS score
5 5 5 5 3 1 1 2 1 3 1 3.22
5 4 3 9 2 2 0 0 2 3 2 3.39
5 6 7 4 2 1 2 4 1 0 0 3.45b
11 19 6 7 8 2 4 3 2 0 0 0 0 1 1 0 0 0 0 0 0 0 2.02b 1.38b
Data presented as n of patients unless otherwise stated. a VAS scores; 0, no pain; 10, worst pain imaginable. b Statistically significant differences between pairwise comparisons (P < 0.05 for all comparisons; Wilcoxon signed-rank test).
The present study is is the first prospective study to examine pain and bone regeneration with a follow-up of 10 years. In this study, we found that pain was significantly lower 3 years postoperatively compared with 1 year postoperatively. This reduction in pain was primarily exhibited because fewer patients reported severe pain as the postoperative time increased. This result may affect the number of orthopaedic surgeons who propose reconstruction of the iliac crest to reduce pain. Several methods to reduce graft site pain are currently available. For example, Tanishima et al.6 recommended rounding off the graft harvest site edges. Reconstruction of the graft site with resorbable mesh has been shown to reduce early postoperative pain.7 Continuous application
of 0.2% ropivacaine through an iliac crest catheter with iliac crest bone grafting was demonstrated to be an effective method for pain relief for the first 48 h, and the benefit of this technique was still present after 3 months.8 However, most of these were retrospective studies with shorter follow-up times, which seriously affected their credibility. This present study revealed a declining trend in pain, which appeared to have started 3 years postoperatively, suggesting that pain relief does not require ilium reconstruction. This present study also observed the phenomenon of bone regeneration. The results demonstrated that the ilium exhibited a good ability to repair itself in the long term. This was perhaps related to the choice of patients, who were younger people (aged 30–40 years) with fractures and no medical comorbidities (ASA physical status of 1 or 2). This present study selected younger rather than older patients with spinal diseases to ensure successful completion of a 10year follow-up; thus, the extent of iliac regeneration may have been exaggerated in this study. This present study sought to determine whether bone regrowth at the harvest site was associated with pain relief, but it was unable to determine this because the sample size was too small. This problem requires further investigation in a multicentre prospective study with a larger sample size. In conclusion, this present study demonstrated that the iliac crest bone graft donor site showed a declining trend in pain over the follow-up period, which may have started at 3 years postoperatively. Analysis of plain radiographs demonstrated that the ilium was readily able to repair itself over the long term. Declaration of conflicting interest The authors declare that there are no conflicts of interest.
Downloaded from imr.sagepub.com at Uniwersytet Warszawski on March 20, 2015
1352
Journal of International Medical Research 42(6)
Funding This research received no specific grant from any funding agency in the public, commercial, or notfor-profit sectors.
5.
References 1. Almaiman M, Al-Bargi HH and Manson P. Complication of anterior iliac bone graft harvesting in 372 adult patients from May 2006 to May 2011 and a literature review. Craniomaxillofac Trauma Reconstr 2013; 6: 257–266. 2. Fasolis M, Boffano P and Ramieri G. Morbidity associated with anterior iliac crest bone graft. Oral Surg Oral Med Oral Pathol Oral Radiol 2012; 114: 586–591. 3. Loeffler BJ, Kellam JF, Sims SH, et al. Prospective observational study of donor-site morbidity following anterior iliac crest bonegrafting in orthopaedic trauma reconstruction patients. J Bone Joint Surg Am 2012; 94: 1649–1654. 4. Ropars M, Zadem A, Morandi X, et al. How can we optimize anterior iliac crest bone
6.
7.
8.
harvesting? An anatomical and radiological study. Eur Spine J 2014; 23: 1150–1155. Skeppholm M and Olerud C. Pain from donor site after anterior cervical fusion with bone graft: a prospective randomized study with 12 months of follow-up. Eur Spine J 2013; 22: 142–147. Tanishima T, Yoshimasu N and Ogai M. A technique for prevention of donor site pain associated with harvesting iliac bone grafts. Surg Neurol 1995; 44: 131–132. Wang MY, Levi AD, Shah S, et al. Polylactic acid mesh reconstruction of the anterior iliac crest after bone harvesting reduces early postoperative pain after anterior cervical fusion surgery. Neurosurgery 2002; 51: 413–416. Blumenthal S, Dullenkopf A, Rentsch K, et al. Continuous infusion of ropivacaine for pain relief after iliac crest bone grafting for shoulder surgery. Anesthesiology 2005; 102: 392–397.
Downloaded from imr.sagepub.com at Uniwersytet Warszawski on March 20, 2015
