Kirners deformity – A systematic review and surgery recommendations

Kirners deformity – A systematic review and surgery recommendations | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Kirners deformity – A systematic review and surgery recommendations Tim Fülling, Carsten Baade, Adrian Dragu, Antek Nicklas This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5374653/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 03 Jan, 2025 Read the published version in Archives of Orthopaedic and Trauma Surgery → Version 1 posted 5 You are reading this latest preprint version Abstract Background: Kirner deformity is a rare anomaly of the little finger in adolescents, characterized by a deformity of the distal phalanx and a radiologically L-shaped epiphysis, along with palmar and radial angulation of the distal phalanx. Due to the rarity of these pathological findings, there are no systematic literature reviews available. This work serves as an overview of the clinical presentation, frequency and age distributions, as well as possible conservative and surgical treatment options. Methods: We present five cases of patients with Kirner’s deformity of the little finger who underwent surgical treatment. A partial tenotomy of the flexor digitorum profundus tendon from the metaphyseal/diaphyseal distal phalanx was performed. In one case, a dorsal epiphysiodesis was also carried out. Additionally, a systematic review of the literature on Kirner’s deformity was conducted, summarizing the prevalence, previously used surgical treatment options, and epidemiological data. Results: In the presented cases, the detachment of the FDP tendon and dorsal epiphysiodesis resulted in a good functional and aesthetic outcome. Regarding the epidemiological distribution of Kirner deformity, it is noted that significantly more females are affected than males (63% vs. 36%). The average age at presentation in the respective clinic was 9.36 years (± 2.5). In more than half of all reported cases, the deformity was bilateral. Surgical intervention was performed in only 7.4% of cases, which included FDP detachment or corrective osteotomies. More than 90% of patients were treated conservatively. Conclusion: Kirner’s deformity is a rare condition affecting adolescents. In cases where functional limitations or pain symptoms are present, we recommend surgical intervention via detachment of the FDP tendon. If the deformity is an incidental finding without functional or aesthetic limitations, conservative therapy with a corrective splint can be initiated. From our perspective, early surgical treatment before the age of 12 improves both the long-term functional and aesthetic outcomes. Kirners deformity hand surgery surgery recommendations dystelephalangy finger deformity Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction The Kirner deformity, first described by Kirner in 1927, is a rare handsurgical anomaly that primarily affects children and adolescents[ 4 ]. It is characterized by a curvature of the distal phalanx of the fifth finger. Due to the rarity of this deformity and the limited scientific literature available, a detailed investigation is necessary to improve understanding and treatment. Clinical Features: Kirner deformity is typically diagnosed in childhood or early adolescence and usually affects both hands. The main characteristics include a visible and palpable curvature of the distal phalanx of the little finger, which is often painless but may be cosmetically concerning. The condition is generally progressive, with the deformity worsening as the child grows. Radiological Findings Radiologically, the deformity presents as a palmar and radial curvature of the distal phalanx of the little finger. In advanced cases, cortical thickening and sclerotic changes may also be observed[ 6 , 7 ]. Etiology: The exact cause of Kirner deformity is unknown. However, genetic factors are suspected to play a role, as familial clustering has been reported[ 2 , 10 ]. A familial inheritance (autosomal dominant) has been described 4 . Developmental disturbances of bone structure during growth may also contribute to the formation of this anomaly[ 8 ]. Diagnostic Methods: The diagnosis of Kirner deformity is primarily made through clinical examination and radiological imaging. X-rays of the affected fingers are the preferred method to visualize the characteristic curvatures and any potential structural bone changes[ 7 ]. Differential Diagnoses: It is important to differentiate Kirner deformity from other conditions that may present with similar clinical and radiological features. These include Klippel-Feil syndrome, Apert syndrome, Enchondromatosis and Clinodactyly[ 9 ]. Therapy: In most cases, no intervention is necessary, as the deformity is usually asymptomatic and does not cause functional impairments. For significant cosmetic or functional concerns, surgical correction may be considered. Surgical options include osteotomies to straighten the affected phalanx[ 1 , 2 ]. Conservative approaches include physical therapy and the use of splints to slow the progression of the deformity. However, these methods have limited efficacy and are rarely employed. Surgical treatment is rarely necessary and is reserved for cases with severe cosmetic or functional impairments. Techniques such as wedge osteotomy to correct the curvature, followed by fixation with K-wires or screws, are possible procedures[ 3 ]. Material and method To gain a deeper understanding of this rare condition, we conducted an extensive literature review using PubMed and Google Scholar. The search terms "Kirner deformity" and "Dystelephalangy" identified 26 publications from 1985 to 2024 (Table.1). Two papers were excluded due to being overview articles without case presentations. We screened the remaining papers with a focus on conservative and surgical treatments of Kirner deformity. Additionally, epidemiological data such as age, gender, and affected finger or side were identified. Table 1 Author Title Cases Surgery? Adeb et al., 2019 Kirner’s deformity of the fifth finger: a case report 1 No Benatar 2004 Kirner’s Deformity Treated by Distal Detachment of the Flexor Digitorum Profundus Tendon 4 Yes (FDP Detachement) Brune et al., 2003 Kirner’s deformity of all fingers in a 5-year-old girl: soft-tissue enhancement with normal bones on contrast-enhanced MRI 1 No Fairbank et al., 2015 The pathogenesis of Kirner’s deformity: A clinical, radiological and histological study 3 Yes (Osteotomy + Kirschner - Wire DIP-Transfixation) Freiberg et al., 1985 Kirner's deformity: A review of the literature and case presentation 63 No Gamo et al., 2014 Percutaneous corrective osteotomy for Kirner's deformity: a case report 1 Yes (percutaneous correction Osteotomy) Gouda et al., 2010 Kirner’s deformity of little finger 1 No Khalid et al., 2012 Kirner’s Deformity Misdiagnosed as Fracture: A Case Report 1 No Lau et al., 2008 Reverse Kirner’s Deformity: Case Report 1 No Lee et al., 2010 MRI findings in Kirner deformity: normal insertion of the flexor Digitorum profundus tendon without soft-tissue enhancement 1 No Moser et al., 1996 A new method for treating the Kirner deformity with the SM-Fix phalangeal distractor 1 Yes (Osteotomy of distal phalanx + SM-Fix-Phalanx-Distractor) Norat et al., 2008 Clinodactylies: Delta Phalanx and Kirner deformity 1 No Satake et al., 2013 Radiographic features of Kirner’s deformity 36 No Song & Koh, 2004 Kirner’s deformity: progressiveness and classification 1 No Sugiura, 1989 Polytopic dystelephalangy of the fingers 1 No Tianxao et al., 2020 Kirner’s deformity of the fifth finger A case report 1 No Würfel et al., 1995 Die Kirner-Deformität 1 No This study performed a comprehensive statistical analysis using the latest version of IBM SPSS Statistics to evaluate the data collected from all included publications. The retrospective evaluation was conducted in accordance with the Declaration of Helsinki. Case series: In this study, we present five cases of Kirner’s deformity of the little finger, all of which were treated surgically. Included were four female and one male patient. In three patient Kirner’s deformity occurred in the left little finger. The other patient presented with deformity in the right little finger. Clinically, all cases showed a painless deformity of the distal phalanx with radial and palmar deviation, while full mobility of the distal interphalangeal joint was preserved, with an average extension/flexion angle of 0-10-80° (Fig. 1 ). The joint itself was stable in each case. The X-ray of a 12-year-old patient exemplifies a widened, L-shaped epiphysis with radial and palmar angulation of the distal phalanx (Fig. 2 ). An outpatient MRI of the same patient revealed a distally inserted flexor tendon without evidence of inflammatory activity in the epiphyseal area (Fig. 3 ). In all cases, we performed a partial tenotomy of the flexor digitorum profundus tendon from the metaphyseal/diaphyseal distal phalanx. In our exemplary case, a dorsal epiphysiodesis was also performed. A radial-sided incision along the neutral axis was made over the distal middle and distal phalanges. Dissection was then carried deeper to the insertion of the FDP tendon in the metaphyseal or diaphyseal region. The tendon insertion was dissected with an 11-blade (Fig. 4 ). Postoperatively, immobilization was achieved using a Chrisofix splint for 2 weeks. Twelve months postoperatively, a significant improvement in palmar tilt by 10° was observed in the patients under 12 years old who underwent surgery. In the 12-year-old patient, however, no radiological axis improvement was seen after 12 months. Results In the analysis of all available English or German publications (n = 26) on Kirner deformity since 1985, a total of 121 cases were identified (Table 1 ). The average age of affected children was 9.36 years (± 2.6). Girls were significantly more affected than boys (F vs. M; 64% vs. 36%). In 56% of published cases, both hands were involved. In cases with unilateral involvement, 30% were affected on the right side and 13% on the left side. In all cases, the affected finger was the little finger. Only one publication by Sugiura reported involvement of the ring and middle fingers in addition to the little finger[ 8 ]. Where available, nearly all cases showed palmar curvature of the finger on X-ray as our presented case. Only in the publication by Lau was there a dorsal angulation, named as an inverse Kirner deformity[ 5 ]. As mentioned earlier, various surgical treatment options are available. Across the included publications, a total of 9 surgeries were performed, accounting for 7.4% of all cases. One-third of the patients underwent a flexor digitorum profundus (FDP) detachment procedure. In one case, a K-wire transfixation of the distal interphalangeal joint was additionally performed to FDP detachment. Fairbank and colleagues performed three surgeries, which involved osteotomy and K-wire distal interphalangeal joint (DIP) transfixation. In another case, an osteotomy of the distal phalanx and the use of an SM-Fix phalangeal distractor were performed (Fig. 5 ). In contrast, 92.5% of the patients did not undergo surgical treatment and were managed conservatively. Indications for surgical treatments were not mentioned clearly. Discussion Primarily, it can be observed that the diagnosis of Kirner’s deformity is made through clinical examination and radiological imaging. Before planned surgical treatment, we recommend performing an MRI to determine the distal insertion of the flexor tendon for FDP detachment. The prognosis of Kirner’s deformity is generally favorable. Since the deformity is typically asymptomatic, the quality of life of affected individuals is usually not impaired. This is reflected by over 90% of conservative cases found in our literature review. In cases where surgical correction was performed, the results are generally satisfactory. From our experience, surgical intervention before the age of 12 should be pursued for better functional and aesthetic outcomes. Long-term follow-up studies on patients have not yet been published. Surgical procedures, such as partial tenotomy of the distal insertion of the flexor digitorum profundus tendon of the little finger, have been described to prevent abnormal growth stimuli. In the five cases we present, this surgical technique led to satisfactory outcomes, both functionally and aesthetically. Since the growth plate gradually closes with age, we recommend surgery before the age of 12 when indicated. Further studies are needed to determine the optimal age for surgery and its correlation with outcomes, as our case numbers are too small for statistically significant conclusions. Kirner’s deformity is a rare, mostly asymptomatic anomaly of the distal phalanx of the little finger. Although the etiology is not fully understood, genetic predisposition likely plays a significant role. Genetic causes were not identified in the papers listed in Box 1. Further research is needed to better understand the genetic and developmental biology underlying Kirner’s deformity. As previous case reports have indicated, female patients are more frequently affected than males, and a genetic link cannot be ruled out. The typical age range of 9 to 12 years aligns with the results of our literature review. Declarations Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. Institutional Review Board Statement The study was conducted in accordance with the Declaration of Helsinki and approved by the Ethics Committee Informed Consent Statement Written informed consent for publication has been obtained from the patients, who can be identified, to publish this paper. Conflicts of Interest The authors declare no conflict of interest. Author Contribution Tim Fülling and Antek Nicklas wrote main manuscript, Carsten Baade was surgeon of 4 cases and provided statistics and patient informations, prepared figures which include xrays. Antek Nicklas prepared each other figures and made the review/statitics All authors reviewed the manuscript.1st Author will be Tim Fülling, Last Author will be Antek Nicklas; All authors agreed in this order References Benatar N (2004) Kirner's deformity treated by distal detachment of the flexor digitorum profundus tendon. Handchir Mikrochir Plast Chir 36(2–3):166–169. 10.1055/s-2004-817890 Fairbank SM, Rozen WM, Coombs CJ (2015) The pathogenesis of Kirner's deformity: A clinical, radiological and histological study. J Hand Surg Eur Vol 40(6):633–637. 10.1177/1753193414551911 Gamo K, Kuriyama K, Uesugi A et al (2014) Percutaneous corrective osteotomy for Kirner's deformity: a case report. J Pediatr Orthop B 23(3):277–281 Kirner J (1927) Doppelseitige Verkrummungen des Kleinfingerendgliedesals selbstfindigesKrankheitsbild. Fortschr Geb Röntgenstr 1927;36(36): 804–6 Lau YJ, Tonkin MA (2009) Reverse Kirner's deformity: case report. J Hand Surg Am 34(3):463–466. 10.1016/j.jhsa.2008.10.024 Lee J, Ahn JK, Choi S-H et al (2010) MRI findings in Kirner deformity: normal insertion of the flexor digitorum profundus tendon without soft-tissue enhancement. Pediatr Radiol 40(9):1572–1575. 10.1007/s00247-010-1628-4 Satake H, Ogino T, Eto J et al (2013) Radiographic features of Kirner's deformity. Congenit Anom (Kyoto) 53(2):78–82. 10.1111/cga.12010 Sugiura Y (1989) 493_1.tif // Polytopic dystelephalangy of the fingers. Pediatr Radiol 19(6–7):493–495 Unglaub F, Langer MF, Hahn P et al (2016) Fehlbildungen an Hand und Unterarm: Postpartal auffallend. Orthopade 45(7):631–642. 10.1007/s00132-016-3282-5 Würfel A, Hofmann-von Kap-herr S, Schumacher R (1995) Würfel 1995 // Die Kirner-Deformität. Klin Padiatr 207(6):356–358 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 03 Jan, 2025 Read the published version in Archives of Orthopaedic and Trauma Surgery → Version 1 posted Editorial decision: Revision requested 24 Nov, 2024 Reviewers invited by journal 02 Nov, 2024 Editor assigned by journal 02 Nov, 2024 Submission checks completed at journal 02 Nov, 2024 First submitted to journal 01 Nov, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5374653","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":376020632,"identity":"34890d0d-8fa0-4afc-a34d-93ffa68bc2b6","order_by":0,"name":"Tim Fülling","email":"","orcid":"","institution":"Abteilung für Plastische und Handchirurgie UniversitätsCentrum für Orthopädie, Unfall- \u0026 Plastische Chirurgie","correspondingAuthor":false,"prefix":"","firstName":"Tim","middleName":"","lastName":"Fülling","suffix":""},{"id":376020633,"identity":"b4533365-4672-4e4e-b549-e464e1e78602","order_by":1,"name":"Carsten Baade","email":"","orcid":"","institution":"Helios Weißeritztal-Kliniken GmbH","correspondingAuthor":false,"prefix":"","firstName":"Carsten","middleName":"","lastName":"Baade","suffix":""},{"id":376020634,"identity":"df9df6bb-4494-43b1-85e7-34bdcdd982e5","order_by":2,"name":"Adrian Dragu","email":"","orcid":"","institution":"Abteilung für Plastische und Handchirurgie UniversitätsCentrum für Orthopädie, Unfall- \u0026 Plastische Chirurgie","correspondingAuthor":false,"prefix":"","firstName":"Adrian","middleName":"","lastName":"Dragu","suffix":""},{"id":376020635,"identity":"be99a1eb-cd67-4e61-9ce7-8e1bdd577fd4","order_by":3,"name":"Antek Nicklas","email":"data:image/png;base64,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","orcid":"","institution":"Abteilung für Plastische und Handchirurgie UniversitätsCentrum für Orthopädie, Unfall- \u0026 Plastische Chirurgie","correspondingAuthor":true,"prefix":"","firstName":"Antek","middleName":"","lastName":"Nicklas","suffix":""}],"badges":[],"createdAt":"2024-11-01 16:38:23","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5374653/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5374653/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00402-024-05724-5","type":"published","date":"2025-01-03T15:57:21+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":70042953,"identity":"4892e5d3-34fa-4f8c-af76-229bfa6847a3","added_by":"auto","created_at":"2024-11-27 18:37:02","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":670782,"visible":true,"origin":"","legend":"\u003cp\u003ePreoperative situation; Kirners deformity of 5th finger in 12 year old patient\u003c/p\u003e","description":"","filename":"image1.png","url":"https://assets-eu.researchsquare.com/files/rs-5374653/v1/dbcceb9b5f551eea7d0ccf06.png"},{"id":70042954,"identity":"6b5de863-4d90-4efa-9f6e-c4fd49a21b34","added_by":"auto","created_at":"2024-11-27 18:37:02","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":143940,"visible":true,"origin":"","legend":"\u003cp\u003epreoperative x-ray with widened, L-shaped epiphysis with radial and palmar angulation of the distal phalanx\u003c/p\u003e","description":"","filename":"image2.png","url":"https://assets-eu.researchsquare.com/files/rs-5374653/v1/1d3a302c85fc78ea621fc573.png"},{"id":70042955,"identity":"a754dfce-d26c-4437-84a4-04686e001f60","added_by":"auto","created_at":"2024-11-27 18:37:02","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":226835,"visible":true,"origin":"","legend":"\u003cp\u003epreoperative MRI with a distally inserted flexor tendon without evidence of inflammatory activity in the epiphyseal area\u003c/p\u003e","description":"","filename":"image3.png","url":"https://assets-eu.researchsquare.com/files/rs-5374653/v1/eea118c389c0e43f285d0c56.png"},{"id":70043957,"identity":"19f74c90-d9ab-4ce6-a410-e6c129ff0415","added_by":"auto","created_at":"2024-11-27 18:45:02","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":761255,"visible":true,"origin":"","legend":"\u003cp\u003eintraoperative situs\u003c/p\u003e","description":"","filename":"image4.png","url":"https://assets-eu.researchsquare.com/files/rs-5374653/v1/b3d040f287aa7a48d1defe2d.png"},{"id":70042952,"identity":"1b832cdc-b663-4a3b-b694-b5e5ee7df536","added_by":"auto","created_at":"2024-11-27 18:37:02","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":91771,"visible":true,"origin":"","legend":"\u003cp\u003esurgical techniques\u003c/p\u003e","description":"","filename":"image5.png","url":"https://assets-eu.researchsquare.com/files/rs-5374653/v1/48fd828d2ad2ddeee6eacd26.png"},{"id":73093238,"identity":"9cbdfd52-5c33-4a6c-8114-6053234de1a5","added_by":"auto","created_at":"2025-01-06 16:11:36","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3222022,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5374653/v1/be888c34-c9cd-4a63-a68d-1dcf85959e9f.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Kirners deformity – A systematic review and surgery recommendations","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe Kirner deformity, first described by Kirner in 1927, is a rare handsurgical anomaly that primarily affects children and adolescents[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. It is characterized by a curvature of the distal phalanx of the fifth finger. Due to the rarity of this deformity and the limited scientific literature available, a detailed investigation is necessary to improve understanding and treatment.\u003c/p\u003e\n\u003ch3\u003eClinical Features:\u003c/h3\u003e\n\u003cp\u003eKirner deformity is typically diagnosed in childhood or early adolescence and usually affects both hands. The main characteristics include a visible and palpable curvature of the distal phalanx of the little finger, which is often painless but may be cosmetically concerning. The condition is generally progressive, with the deformity worsening as the child grows.\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eRadiological Findings\u003c/strong\u003e \u003cp\u003eRadiologically, the deformity presents as a palmar and radial curvature of the distal phalanx of the little finger. In advanced cases, cortical thickening and sclerotic changes may also be observed[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e \u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eEtiology:\u003c/h2\u003e \u003cp\u003eThe exact cause of Kirner deformity is unknown. However, genetic factors are suspected to play a role, as familial clustering has been reported[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. A familial inheritance (autosomal dominant) has been described\u003csup\u003e4\u003c/sup\u003e. Developmental disturbances of bone structure during growth may also contribute to the formation of this anomaly[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eDiagnostic Methods:\u003c/h3\u003e\n\u003cp\u003eThe diagnosis of Kirner deformity is primarily made through clinical examination and radiological imaging. X-rays of the affected fingers are the preferred method to visualize the characteristic curvatures and any potential structural bone changes[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e\n\u003ch3\u003eDifferential Diagnoses:\u003c/h3\u003e\n\u003cp\u003eIt is important to differentiate Kirner deformity from other conditions that may present with similar clinical and radiological features. These include Klippel-Feil syndrome, Apert syndrome, Enchondromatosis and Clinodactyly[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e\n\u003ch3\u003eTherapy:\u003c/h3\u003e\n\u003cp\u003eIn most cases, no intervention is necessary, as the deformity is usually asymptomatic and does not cause functional impairments. For significant cosmetic or functional concerns, surgical correction may be considered. Surgical options include osteotomies to straighten the affected phalanx[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Conservative approaches include physical therapy and the use of splints to slow the progression of the deformity. However, these methods have limited efficacy and are rarely employed. Surgical treatment is rarely necessary and is reserved for cases with severe cosmetic or functional impairments. Techniques such as wedge osteotomy to correct the curvature, followed by fixation with K-wires or screws, are possible procedures[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e"},{"header":"Material and method","content":"\u003cp\u003eTo gain a deeper understanding of this rare condition, we conducted an extensive literature review using PubMed and Google Scholar. The search terms \"Kirner deformity\" and \"Dystelephalangy\" identified 26 publications from 1985 to 2024 (Table.1). Two papers were excluded due to being overview articles without case presentations. We screened the remaining papers with a focus on conservative and surgical treatments of Kirner deformity. Additionally, epidemiological data such as age, gender, and affected finger or side were identified.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e\u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAuthor\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTitle\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCases\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eSurgery?\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAdeb et al., 2019\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKirner\u0026rsquo;s deformity of the fifth finger:\u003c/p\u003e \u003cp\u003ea case report\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBenatar 2004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKirner\u0026rsquo;s Deformity Treated by Distal Detachment of the Flexor Digitorum Profundus Tendon\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eYes (FDP Detachement)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBrune et al., 2003\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKirner\u0026rsquo;s deformity of all fingers in a 5-year-old girl:\u003c/p\u003e \u003cp\u003esoft-tissue enhancement with normal bones on contrast-enhanced MRI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFairbank et al., 2015\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eThe pathogenesis of Kirner\u0026rsquo;s deformity:\u003c/p\u003e \u003cp\u003eA clinical, radiological and histological study\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eYes (Osteotomy\u0026thinsp;+\u0026thinsp;Kirschner - Wire DIP-Transfixation)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFreiberg et al., 1985\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKirner's deformity: A review of the literature and\u003c/p\u003e \u003cp\u003ecase presentation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGamo et al., 2014\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePercutaneous corrective osteotomy for Kirner's deformity:\u003c/p\u003e \u003cp\u003ea case report\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eYes (percutaneous correction Osteotomy)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGouda et al., 2010\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKirner\u0026rsquo;s deformity of little finger\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eKhalid et al., 2012\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKirner\u0026rsquo;s Deformity Misdiagnosed as Fracture: \u003c/p\u003e \u003cp\u003eA Case Report\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLau et al., 2008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eReverse Kirner\u0026rsquo;s Deformity: \u003c/p\u003e \u003cp\u003eCase Report\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLee et al., 2010\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMRI findings in Kirner deformity: normal insertion\u003c/p\u003e \u003cp\u003eof the flexor Digitorum profundus tendon\u003c/p\u003e \u003cp\u003ewithout soft-tissue enhancement\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMoser et al., 1996\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eA new method for treating the Kirner deformity with the SM-Fix phalangeal distractor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eYes (Osteotomy of distal phalanx\u0026thinsp;+\u0026thinsp;SM-Fix-Phalanx-Distractor)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNorat et al., 2008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eClinodactylies: \u003c/p\u003e \u003cp\u003eDelta Phalanx and Kirner deformity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSatake et al., 2013\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRadiographic features of Kirner\u0026rsquo;s deformity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSong \u0026amp; Koh, 2004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKirner\u0026rsquo;s deformity: \u003c/p\u003e \u003cp\u003eprogressiveness and classification\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSugiura, 1989\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePolytopic dystelephalangy of the fingers\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTianxao et al., 2020\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKirner\u0026rsquo;s deformity of the fifth finger\u003c/p\u003e \u003cp\u003eA case report\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eW\u0026uuml;rfel et al., 1995\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDie Kirner-Deformit\u0026auml;t\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThis study performed a comprehensive statistical analysis using the latest version of IBM SPSS Statistics to evaluate the data collected from all included publications. The retrospective evaluation was conducted in accordance with the Declaration of Helsinki.\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eCase series:\u003c/h2\u003e \u003cp\u003eIn this study, we present five cases of Kirner\u0026rsquo;s deformity of the little finger, all of which were treated surgically. Included were four female and one male patient. In three patient Kirner\u0026rsquo;s deformity occurred in the left little finger. The other patient presented with deformity in the right little finger. Clinically, all cases showed a painless deformity of the distal phalanx with radial and palmar deviation, while full mobility of the distal interphalangeal joint was preserved, with an average extension/flexion angle of 0-10-80\u0026deg; (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The joint itself was stable in each case. The X-ray of a 12-year-old patient exemplifies a widened, L-shaped epiphysis with radial and palmar angulation of the distal phalanx (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eAn outpatient MRI of the same patient revealed a distally inserted flexor tendon without evidence of inflammatory activity in the epiphyseal area (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). In all cases, we performed a partial tenotomy of the flexor digitorum profundus tendon from the metaphyseal/diaphyseal distal phalanx. In our exemplary case, a dorsal epiphysiodesis was also performed. A radial-sided incision along the neutral axis was made over the distal middle and distal phalanges. Dissection was then carried deeper to the insertion of the FDP tendon in the metaphyseal or diaphyseal region. The tendon insertion was dissected with an 11-blade (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003cp\u003ePostoperatively, immobilization was achieved using a Chrisofix splint for 2 weeks.\u003c/p\u003e \u003cp\u003eTwelve months postoperatively, a significant improvement in palmar tilt by 10\u0026deg; was observed in the patients under 12 years old who underwent surgery. In the 12-year-old patient, however, no radiological axis improvement was seen after 12 months.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eIn the analysis of all available English or German publications (n\u0026thinsp;=\u0026thinsp;26) on Kirner deformity since 1985, a total of 121 cases were identified (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The average age of affected children was 9.36 years (\u0026plusmn;\u0026thinsp;2.6). Girls were significantly more affected than boys (F vs. M; 64% vs. 36%). In 56% of published cases, both hands were involved. In cases with unilateral involvement, 30% were affected on the right side and 13% on the left side. In all cases, the affected finger was the little finger. Only one publication by Sugiura reported involvement of the ring and middle fingers in addition to the little finger[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWhere available, nearly all cases showed palmar curvature of the finger on X-ray as our presented case. Only in the publication by Lau was there a dorsal angulation, named as an inverse Kirner deformity[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAs mentioned earlier, various surgical treatment options are available. Across the included publications, a total of 9 surgeries were performed, accounting for 7.4% of all cases. One-third of the patients underwent a flexor digitorum profundus (FDP) detachment procedure. In one case, a K-wire transfixation of the distal interphalangeal joint was additionally performed to FDP detachment. Fairbank and colleagues performed three surgeries, which involved osteotomy and K-wire distal interphalangeal joint (DIP) transfixation. In another case, an osteotomy of the distal phalanx and the use of an SM-Fix phalangeal distractor were performed (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn contrast, 92.5% of the patients did not undergo surgical treatment and were managed conservatively. Indications for surgical treatments were not mentioned clearly.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003ePrimarily, it can be observed that the diagnosis of Kirner\u0026rsquo;s deformity is made through clinical examination and radiological imaging. Before planned surgical treatment, we recommend performing an MRI to determine the distal insertion of the flexor tendon for FDP detachment.\u003c/p\u003e \u003cp\u003eThe prognosis of Kirner\u0026rsquo;s deformity is generally favorable. Since the deformity is typically asymptomatic, the quality of life of affected individuals is usually not impaired. This is reflected by over 90% of conservative cases found in our literature review. In cases where surgical correction was performed, the results are generally satisfactory. From our experience, surgical intervention before the age of 12 should be pursued for better functional and aesthetic outcomes. Long-term follow-up studies on patients have not yet been published.\u003c/p\u003e \u003cp\u003eSurgical procedures, such as partial tenotomy of the distal insertion of the flexor digitorum profundus tendon of the little finger, have been described to prevent abnormal growth stimuli. In the five cases we present, this surgical technique led to satisfactory outcomes, both functionally and aesthetically. Since the growth plate gradually closes with age, we recommend surgery before the age of 12 when indicated. Further studies are needed to determine the optimal age for surgery and its correlation with outcomes, as our case numbers are too small for statistically significant conclusions.\u003c/p\u003e \u003cp\u003eKirner\u0026rsquo;s deformity is a rare, mostly asymptomatic anomaly of the distal phalanx of the little finger. Although the etiology is not fully understood, genetic predisposition likely plays a significant role. Genetic causes were not identified in the papers listed in Box 1. Further research is needed to better understand the genetic and developmental biology underlying Kirner\u0026rsquo;s deformity.\u003c/p\u003e \u003cp\u003eAs previous case reports have indicated, female patients are more frequently affected than males, and a genetic link cannot be ruled out. The typical age range of 9 to 12 years aligns with the results of our literature review.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInstitutional Review Board Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study was conducted in accordance with the Declaration of Helsinki and approved by the Ethics Committee\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInformed Consent Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten informed consent for publication has been obtained from the patients, who can be identified, to publish this paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of Interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no conflict of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contribution\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTim F\u0026uuml;lling and Antek Nicklas wrote main manuscript, Carsten Baade was surgeon of 4 cases and provided statistics and patient informations, prepared figures which include xrays. Antek Nicklas prepared each other figures and made the review/statitics All authors reviewed the manuscript.1st Author will be Tim F\u0026uuml;lling, Last Author will be Antek Nicklas; All authors agreed in this order\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eBenatar N (2004) Kirner's deformity treated by distal detachment of the flexor digitorum profundus tendon. Handchir Mikrochir Plast Chir 36(2\u0026ndash;3):166\u0026ndash;169. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1055/s-2004-817890\u003c/span\u003e\u003cspan address=\"10.1055/s-2004-817890\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFairbank SM, Rozen WM, Coombs CJ (2015) The pathogenesis of Kirner's deformity: A clinical, radiological and histological study. J Hand Surg Eur Vol 40(6):633\u0026ndash;637. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1177/1753193414551911\u003c/span\u003e\u003cspan address=\"10.1177/1753193414551911\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGamo K, Kuriyama K, Uesugi A et al (2014) Percutaneous corrective osteotomy for Kirner's deformity: a case report. J Pediatr Orthop B 23(3):277\u0026ndash;281\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKirner J (1927) Doppelseitige Verkrummungen des Kleinfingerendgliedesals selbstfindigesKrankheitsbild. Fortschr Geb R\u0026ouml;ntgenstr 1927;36(36): 804\u0026ndash;6\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLau YJ, Tonkin MA (2009) Reverse Kirner's deformity: case report. J Hand Surg Am 34(3):463\u0026ndash;466. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.jhsa.2008.10.024\u003c/span\u003e\u003cspan address=\"10.1016/j.jhsa.2008.10.024\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLee J, Ahn JK, Choi S-H et al (2010) MRI findings in Kirner deformity: normal insertion of the flexor digitorum profundus tendon without soft-tissue enhancement. Pediatr Radiol 40(9):1572\u0026ndash;1575. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s00247-010-1628-4\u003c/span\u003e\u003cspan address=\"10.1007/s00247-010-1628-4\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSatake H, Ogino T, Eto J et al (2013) Radiographic features of Kirner's deformity. 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Orthopade 45(7):631\u0026ndash;642. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s00132-016-3282-5\u003c/span\u003e\u003cspan address=\"10.1007/s00132-016-3282-5\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eW\u0026uuml;rfel A, Hofmann-von Kap-herr S, Schumacher R (1995) W\u0026uuml;rfel 1995 // Die Kirner-Deformit\u0026auml;t. Klin Padiatr 207(6):356\u0026ndash;358\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"archives-of-orthopaedic-and-trauma-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"aots","sideBox":"Learn more about [Archives of Orthopaedic and Trauma Surgery](http://link.springer.com/journal/402)","snPcode":"402","submissionUrl":"https://submission.springernature.com/new-submission/402/3","title":"Archives of Orthopaedic and Trauma Surgery","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Kirners deformity, hand surgery, surgery recommendations, dystelephalangy, finger deformity","lastPublishedDoi":"10.21203/rs.3.rs-5374653/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5374653/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Kirner deformity is a rare anomaly of the little finger in adolescents, characterized by a deformity of the distal phalanx and a radiologically L-shaped epiphysis, along with palmar and radial angulation of the distal phalanx. Due to the rarity of these pathological findings, there are no systematic literature reviews available. This work serves as an overview of the clinical presentation, frequency and age distributions, as well as possible conservative and surgical treatment options.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eWe present five cases of patients with Kirner’s deformity of the little finger who underwent surgical treatment. A partial tenotomy of the flexor digitorum profundus tendon from the metaphyseal/diaphyseal distal phalanx was performed. In one case, a dorsal epiphysiodesis was also carried out.\u003c/p\u003e\n\u003cp\u003eAdditionally, a systematic review of the literature on Kirner’s deformity was conducted, summarizing the prevalence, previously used surgical treatment options, and epidemiological data.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e In the presented cases, the detachment of the FDP tendon and dorsal epiphysiodesis resulted in a good functional and aesthetic outcome. Regarding the epidemiological distribution of Kirner deformity, it is noted that significantly more females are affected than males (63% vs. 36%). The average age at presentation in the respective clinic was 9.36 years (± 2.5). In more than half of all reported cases, the deformity was bilateral. Surgical intervention was performed in only 7.4% of cases, which included FDP detachment or corrective osteotomies. More than 90% of patients were treated conservatively.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eKirner’s deformity is a rare condition affecting adolescents. In cases where functional limitations or pain symptoms are present, we recommend surgical intervention via detachment of the FDP tendon. If the deformity is an incidental finding without functional or aesthetic limitations, conservative therapy with a corrective splint can be initiated. From our perspective, early surgical treatment before the age of 12 improves both the long-term functional and aesthetic outcomes.\u003c/p\u003e","manuscriptTitle":"Kirners deformity – A systematic review and surgery recommendations","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-11-27 18:36:57","doi":"10.21203/rs.3.rs-5374653/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-11-24T13:07:40+00:00","index":"","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-11-02T07:03:50+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-11-02T06:19:34+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-11-02T06:19:08+00:00","index":"","fulltext":""},{"type":"submitted","content":"Archives of Orthopaedic and Trauma Surgery","date":"2024-11-01T16:36:12+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"archives-of-orthopaedic-and-trauma-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"aots","sideBox":"Learn more about [Archives of Orthopaedic and Trauma Surgery](http://link.springer.com/journal/402)","snPcode":"402","submissionUrl":"https://submission.springernature.com/new-submission/402/3","title":"Archives of Orthopaedic and Trauma Surgery","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"c3d3a290-a3d1-47a2-b94a-5215c138373b","owner":[],"postedDate":"November 27th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-01-06T16:00:57+00:00","versionOfRecord":{"articleIdentity":"rs-5374653","link":"https://doi.org/10.1007/s00402-024-05724-5","journal":{"identity":"archives-of-orthopaedic-and-trauma-surgery","isVorOnly":false,"title":"Archives of Orthopaedic and Trauma Surgery"},"publishedOn":"2025-01-03 15:57:21","publishedOnDateReadable":"January 3rd, 2025"},"versionCreatedAt":"2024-11-27 18:36:57","video":"","vorDoi":"10.1007/s00402-024-05724-5","vorDoiUrl":"https://doi.org/10.1007/s00402-024-05724-5","workflowStages":[]},"version":"v1","identity":"rs-5374653","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5374653","identity":"rs-5374653","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}