{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T02:49:47Z","timestamp":1777603787856,"version":"3.51.4"},"reference-count":56,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,2,10]],"date-time":"2025-02-10T00:00:00Z","timestamp":1739145600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background\/Objectives: Stress concentration around distal screw-removal holes confers a major risk for periprosthetic fractures following conversion total hip arthroplasty (cTHA) for intertrochanteric femoral fractures. Optimal stem-selection criteria and guidelines for cTHA can improve clinical outcomes. We determined the influence of the cementless stem length on the stress distribution around distal screw-removal holes. Methods: For the finite element analysis, institutional data from preoperative CT scans of contralateral femurs of patients who underwent THA were used. To replicate the post-nail-removal state, we used 3D registration of standard triangulated language data of the intramedullary nail as an unused material to simulate distal screw-removal holes, located 135 mm from the proximal end of the intramedullary nail. Cementless stems of 130, 140, 150, and 160 mm were individually registered using STL data, and cTHA models were constructed accordingly. Using simulations under load conditions representing normal walking and stair climbing, the mean and maximum equivalent stress values around the distal screw-removal holes were calculated. For multiple comparisons, repeated-measures ANOVA with Bonferroni correction was employed. Results: Compared to the 130 mm stem, the 150 mm and 160 mm stems similarly reduced the maximum equivalent stress around the distal screw-removal holes, although the 140 mm stem showed no significant difference with other stems. Conclusions: A \u2265150 mm stem length reliably mitigated stress concentration around distal screw-removal holes post-cTHA; it is the optimal choice for balancing effectiveness and risk of complications and may contribute to improved long-term clinical outcomes. This study provides practical evidence for stem selection in cTHA and offers valuable insights for future treatment guidelines.<\/jats:p>","DOI":"10.3390\/jcm14041141","type":"journal-article","created":{"date-parts":[[2025,2,10]],"date-time":"2025-02-10T06:43:07Z","timestamp":1739169787000},"page":"1141","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Optimizing Stem Length in Conversion Total Hip Arthroplasty: An Expanded Finite Element Analysis"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9495-837X","authenticated-orcid":false,"given":"Koshiro","family":"Shimasaki","sequence":"first","affiliation":[{"name":"Department of Orthopaedic Surgery, Institute of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba 305-8575, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6755-4900","authenticated-orcid":false,"given":"Tomofumi","family":"Nishino","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Institute of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba 305-8575, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tomohiro","family":"Yoshizawa","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Institute of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba 305-8575, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6675-5244","authenticated-orcid":false,"given":"Ryunosuke","family":"Watanabe","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Institute of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba 305-8575, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fumi","family":"Hirose","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Institute of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba 305-8575, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shota","family":"Yasunaga","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Institute of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba 305-8575, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hajime","family":"Mishima","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Institute of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba 305-8575, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,10]]},"reference":[{"key":"ref_1","unstructured":"(2025, January 15). Hip Fracture: Management, Available online: https:\/\/www.ncbi.nlm.nih.gov\/books\/NBK553768\/."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e1291","DOI":"10.5435\/JAAOS-D-22-00273","article-title":"AAOS clinical practice guideline summary: Management of hip fractures in older adults","volume":"30","author":"Switzer","year":"2022","journal-title":"J. Am. Acad. Orthop. Surg."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"719","DOI":"10.1007\/s00264-009-0837-7","article-title":"Tip-apex distance of intramedullary devices as a predictor of cut-out failure in the treatment of peritrochanteric elderly hip fractures","volume":"34","author":"Geller","year":"2010","journal-title":"Int. Orthop."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"e108","DOI":"10.3928\/01477447-20151222-11","article-title":"Complications after hip nailing for fractures","volume":"39","author":"Mavrogenis","year":"2016","journal-title":"Orthopedics"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"231","DOI":"10.1007\/s12570-012-0133-7","article-title":"Hip arthroplasty after failed nailing of proximal femoral fractures","volume":"3","author":"Mokka","year":"2012","journal-title":"Eur. Orthop. Traumatol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"351","DOI":"10.1007\/s00402-017-2863-z","article-title":"Predictors of cut-out after cephalomedullary nail fixation of pertrochanteric fractures: A retrospective study of 813 patients","volume":"138","author":"Murena","year":"2018","journal-title":"Arch. Orthop. Trauma Surg."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2775","DOI":"10.1007\/s00264-022-05529-4","article-title":"Salvage hip replacement after cut-out failure of cephalomedullary nail fixation for proximal femur fractures: A case series describing the technique and results","volume":"46","year":"2022","journal-title":"Int. Orthop."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"168","DOI":"10.1016\/j.arth.2012.04.003","article-title":"Total hip arthroplasty after failed internal fixation of proximal femoral fractures","volume":"28","author":"Archibeck","year":"2013","journal-title":"J. Arthroplast."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"S155","DOI":"10.1016\/j.arth.2020.12.023","article-title":"How does conversion total hip arthroplasty compare to primary?","volume":"36","author":"Douglas","year":"2021","journal-title":"J. Arthroplast."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"763","DOI":"10.5312\/wjo.v14.i10.763","article-title":"Total hip arthroplasty following the failure of intertrochanteric nailing: First implant or salvage surgery?","volume":"14","author":"Solarino","year":"2023","journal-title":"World J. Orthop."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"491","DOI":"10.1080\/17453670710014130","article-title":"Total hip replacement after femoral neck fractures in elderly patients: Results of 8,577 fractures reported to the Norwegian Arthroplasty Register","volume":"78","author":"Gjertsen","year":"2007","journal-title":"Acta Orthop."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"417","DOI":"10.1007\/s00402-017-2631-0","article-title":"Total hip arthroplasty after failed treatment of proximal femur fracture","volume":"137","author":"Tetsunaga","year":"2017","journal-title":"Arch. Orthop. Trauma Surg."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"222","DOI":"10.1007\/BF00441837","article-title":"Hip arthroplasty for failed internal fixation of intertrochanteric and subtrochanteric fractures in the elderly patient","volume":"113","author":"Haentjens","year":"1994","journal-title":"Arch. Orthop. Trauma Surg."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"899","DOI":"10.2106\/00004623-200305000-00019","article-title":"Hip arthroplasty for salvage of failed treatment of intertrochanteric hip fractures","volume":"85","author":"Haidukewych","year":"2003","journal-title":"J. Bone Jt. Surg. Am."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"682","DOI":"10.1016\/j.arth.2005.08.013","article-title":"Short-term outcomes of total hip arthroplasty after complications of open reduction internal fixation for hip fracture","volume":"21","author":"Winemaker","year":"2006","journal-title":"J. Arthroplast."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1055","DOI":"10.1007\/s00198-023-06695-w","article-title":"Periprosthetic fractures: An unrecognized osteoporosis crisis","volume":"34","author":"Binkley","year":"2023","journal-title":"Osteoporos. Int."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"461","DOI":"10.1302\/0301-620X.98B4.37201","article-title":"Epidemiology of periprosthetic fracture of the femur in 32 644 primary total hip arthroplasties: A 40-year experience","volume":"98-B","author":"Abdel","year":"2016","journal-title":"Bone Jt. J."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"41","DOI":"10.4055\/cios23157","article-title":"Age as a risk factor for intraoperative periprosthetic femoral fractures in cementless hip hemiarthroplasty for femoral neck fractures: A retrospective analysis","volume":"16","author":"Ashkenazi","year":"2024","journal-title":"Clin. Orthop. Surg."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"681","DOI":"10.1016\/j.otsr.2018.04.015","article-title":"Total hip arthroplasty after failed fixation of a proximal femur fracture: Analysis of 59 cases of intra- and extra-capsular fractures","volume":"104","author":"Morice","year":"2018","journal-title":"Orthop. Traumatol. Surg. Res."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"101243","DOI":"10.1016\/j.artd.2023.101243","article-title":"Total hip arthroplasty after proximal femoral nailing: Preoperative preparation and intraoperative surgical techniques","volume":"24","author":"Puri","year":"2023","journal-title":"Arthroplast. Today"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"569","DOI":"10.1016\/j.medengphy.2012.06.023","article-title":"Biomechanical consideration of total hip arthroplasty following failed fixation of femoral intertrochanteric fractures\u2014A finite element analysis","volume":"35","author":"Chen","year":"2013","journal-title":"Med. Eng. Phys."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"238","DOI":"10.1097\/00003086-199606000-00029","article-title":"Periprosthetic fractures of the femur. An analysis of 93 fractures","volume":"327","author":"Beals","year":"1996","journal-title":"Clin. Orthop. Relat. Res."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"855","DOI":"10.1016\/j.arth.2012.10.027","article-title":"Salvage hip arthroplasty after failed fixation of proximal femur fractures","volume":"28","author":"DeHaan","year":"2013","journal-title":"J. Arthroplast."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1999","DOI":"10.1016\/j.arth.2015.05.041","article-title":"Total hip arthroplasty using non-modular cementless long-stem distal fixation for salvage of failed internal fixation of intertrochanteric fracture","volume":"30","author":"Shi","year":"2015","journal-title":"J. Arthroplast."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"398","DOI":"10.1016\/j.arth.2010.01.103","article-title":"Management of failed trochanteric fracture fixation with cementless modular hip arthroplasty using a distally fixing stem","volume":"26","author":"Thakur","year":"2011","journal-title":"J. Arthroplast."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"713","DOI":"10.1016\/j.injury.2019.01.018","article-title":"Cementless total hip arthroplasty following failed internal fixation for femoral neck and intertrochanteric fractures: A comparative study with 3-13 years\u2019 follow-up of 96 consecutive patients\u2019","volume":"50","author":"Moon","year":"2019","journal-title":"Injury"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"3438","DOI":"10.1016\/j.arth.2017.06.032","article-title":"Hip arthroplasty after surgical treatment of intertrochanteric hip fractures","volume":"32","author":"Yuan","year":"2017","journal-title":"J. Arthroplast."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"939","DOI":"10.1007\/s00264-009-0834-x","article-title":"Hip arthroplasty for failed treatment of proximal femoral fractures","volume":"34","author":"Perugia","year":"2010","journal-title":"Int. Orthop."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"471","DOI":"10.1097\/BOT.0b013e3181acfc8c","article-title":"Salvage of failed hip fracture fixation","volume":"23","author":"Angelini","year":"2009","journal-title":"J. Orthop. Trauma"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"452","DOI":"10.1302\/0301-620X.98B4.36922","article-title":"Outcomes of total hip arthroplasty, as a salvage procedure, following failed internal fixation of intracapsular fractures of the femoral neck: A systematic review and meta-analysis","volume":"98-B","author":"Mahmoud","year":"2016","journal-title":"Bone Jt. J."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1593","DOI":"10.1016\/j.arth.2016.12.018","article-title":"Conversion hip arthroplasty in failed fixation of intertrochanteric fracture: A propensity score matching study","volume":"32","author":"Lee","year":"2017","journal-title":"J. Arthroplast."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Zeng, X., Zhan, K., Zhang, L., Zeng, D., Yu, W., Zhang, X., and Zhao, M. (2017). Conversion to total hip arthroplasty after failed proximal femoral nail antirotations or dynamic hip screw fixations for stable intertrochanteric femur fractures: A retrospective study with a minimum follow-up of 3 years. BMC Musculoskelet. Disord., 18.","DOI":"10.1186\/s12891-017-1415-6"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"776","DOI":"10.2106\/00004623-199072050-00021","article-title":"Total hip arthroplasty for complications of intertrochanteric fracture. A technical note","volume":"72","author":"Patterson","year":"1990","journal-title":"J. Bone Jt. Surg. Am."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"142","DOI":"10.1097\/00003086-198707000-00019","article-title":"Femoral cement removal in revision total hip arthroplasty. A biomechanical analysis","volume":"220","author":"Dennis","year":"1987","journal-title":"Clin. Orthop. Relat. Res."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"414","DOI":"10.1002\/jor.1100090314","article-title":"Bypassing femoral cortical defects with cemented intramedullary stems","volume":"9","author":"Larson","year":"1991","journal-title":"J. Orthop. Res."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"164","DOI":"10.1097\/00003086-199306000-00018","article-title":"Femoral windows in revision total hip arthroplasty","volume":"291","author":"Klein","year":"1993","journal-title":"Clin. Orthop. Relat. Res."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Shimasaki, K., Nishino, T., Yoshizawa, T., Watanabe, R., Hirose, F., Yasunaga, S., and Mishima, H. (2025). Stress Analysis in Conversion Total Hip Arthroplasty: A Finite Element Analysis on Stem Length and Distal Screw Hole. J. Clin. Med., 14.","DOI":"10.20944\/preprints202501.1327.v1"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"124","DOI":"10.1111\/os.13574","article-title":"Conversion hip arthroplasty using standard and long stems after failed internal fixation of intertrochanteric fractures","volume":"15","author":"Shi","year":"2023","journal-title":"Orthop. Surg."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"231","DOI":"10.1016\/8756-3282(93)90146-2","article-title":"Structural and cellular assessment of bone quality of proximal femur","volume":"14","author":"Dorr","year":"1993","journal-title":"Bone"},{"key":"ref_40","unstructured":"(2024, November 20). Universia Stem. Available online: https:\/\/formedic.teijin-nakashima.co.jp\/products\/detail\/?id=524."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"1731","DOI":"10.1016\/j.arth.2013.04.034","article-title":"Comparison of mechanical stress and change in bone mineral density between two types of femoral implant using finite element analysis","volume":"28","author":"Hirata","year":"2013","journal-title":"J. Arthroplast."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1876","DOI":"10.1016\/j.injury.2019.09.004","article-title":"Potential bone fragility of mid-shaft atypical femoral fracture: Biomechanical analysis by a CT-based nonlinear finite element method","volume":"50","author":"Tano","year":"2019","journal-title":"Injury"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1016\/S0021-9290(97)00123-1","article-title":"Prediction of femoral fracture load using automated finite element modeling","volume":"31","author":"Keyak","year":"1998","journal-title":"J. Biomech."},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Bergmann, G., Bender, A., Dymke, J., Duda, G., and Damm, P. (2016). Standardized loads acting in hip implants. PLoS ONE, 11.","DOI":"10.1371\/journal.pone.0155612"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"1155","DOI":"10.1016\/j.jbiomech.2004.05.022","article-title":"Determination of muscle loading at the hip joint for use in pre-clinical testing","volume":"38","author":"Heller","year":"2005","journal-title":"J. Biomech."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"711","DOI":"10.1007\/s00402-010-1218-9","article-title":"Frictional and bone ingrowth properties of engineered surface topographies produced by electron beam technology","volume":"131","author":"Biemond","year":"2011","journal-title":"Arch. Orthop. Trauma Surg."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1097\/00003086-198810000-00015","article-title":"The anatomic basis of femoral component design","volume":"235","author":"Noble","year":"1988","journal-title":"Clin. Orthop. Relat. Res."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"329","DOI":"10.1016\/j.arth.2003.10.010","article-title":"Hip arthroplasty for failed internal fixation of intertrochanteric fractures","volume":"19","author":"Zhang","year":"2004","journal-title":"J. Arthroplast."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"447","DOI":"10.1002\/jor.1100030407","article-title":"Effect of femoral stem length on stress raisers associated with revision hip arthroplasty","volume":"3","author":"Panjabi","year":"1985","journal-title":"J. Orthop. Res."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"851","DOI":"10.1002\/jor.1100080610","article-title":"Torsional strength reduction due to cortical defects in bone","volume":"8","author":"Edgerton","year":"1990","journal-title":"J. Orthop. Res."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"797","DOI":"10.1007\/s00402-010-1093-4","article-title":"The effect of 4 mm bicortical drill hole defect on bone strength in a pig femur model","volume":"130","author":"Ho","year":"2010","journal-title":"Arch. Orthop. Trauma Surg."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"443","DOI":"10.1007\/s11832-014-0606-z","article-title":"The change in energy absorbed post removal of metalwork in a simulated paediatric long bone fracture","volume":"8","author":"Howieson","year":"2014","journal-title":"J. Child. Orthop."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"507","DOI":"10.2106\/00004623-197052030-00008","article-title":"The biomechanics of torsional fractures. The stress concentration effect of a drill hole","volume":"52","author":"Brooks","year":"1970","journal-title":"J. Bone Jt. Surg. Am."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"1067","DOI":"10.1016\/j.arth.2013.10.016","article-title":"Periprosthetic fracture torque for Short versus Standard cemented hip stems: An experimental in vitro study","volume":"29","author":"Morishima","year":"2014","journal-title":"J. Arthroplast."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"849","DOI":"10.1007\/s00402-008-0676-9","article-title":"Do short-stemmed-prostheses induce periprosthetic fractures earlier than standard hip stems? A biomechanical ex-vivo study of two different stem designs","volume":"129","author":"Jakubowitz","year":"2009","journal-title":"Arch. Orthop. Trauma Surg."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"666","DOI":"10.1016\/j.clinbiomech.2010.04.013","article-title":"Biomechanics of short hip endoprostheses\u2014The risk of bone failure increases with decreasing implant size","volume":"25","author":"Bishop","year":"2010","journal-title":"Clin. Biomech."}],"container-title":["Journal of Clinical Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2077-0383\/14\/4\/1141\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T16:30:27Z","timestamp":1760027427000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2077-0383\/14\/4\/1141"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,2,10]]},"references-count":56,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2025,2]]}},"alternative-id":["jcm14041141"],"URL":"https:\/\/doi.org\/10.3390\/jcm14041141","relation":{},"ISSN":["2077-0383"],"issn-type":[{"value":"2077-0383","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,2,10]]}}}