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Primary treatment of type B post-axial ulnar polydactyly: A systematic review and meta-analysis

  • Harsh Samarendra
    Correspondence
    Corresponding author.
    Affiliations
    Department of Plastic and Reconstructive Surgery, Imperial College Healthcare NHS Trust, Flat 2, 17 Wyfold Road, London SW6 6SE, UK
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  • Ryckie G. Wade
    Affiliations
    Department of Plastic and Reconstructive Surgery, Leeds Teaching Hospitals Trust, Leeds, UK

    Faculty of Medicine and Health Sciences, University of Leeds, Leeds, UK
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  • Louise Glanvill
    Affiliations
    Department of Plastic and Reconstructive Surgery, Oxford University Hospitals NHS Foundation Trust, UK
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  • Justin Wormald
    Affiliations
    Department of Plastic and Reconstructive Surgery, Buckinghamshire Healthcare NHS Trust, Aylesbury, UK

    Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK
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  • Abhilash Jain
    Affiliations
    Department of Plastic and Reconstructive Surgery, Imperial College Healthcare NHS Trust, Flat 2, 17 Wyfold Road, London SW6 6SE, UK

    Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK
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Open AccessPublished:May 13, 2022DOI:https://doi.org/10.1016/j.jpra.2022.05.002

      Abstract

      Optimal management of pedunculated ulnar polydactyly is not defined. This systematic review summarises objective and patient-reported outcomes following primary treatment. Two authors screened articles for inclusion according to a PROSPERO published protocol. The meta-analysis of adverse events was performed, and a narrative synthesis of satisfaction and patient-reported outcomes was reported. The risk of bias was assessed using Cochrane's ROBINS-I tool. Of 1650 articles identified, 15 were eligible, including 13 single-arm and 2 multi-arm studies. Complications were 6 times as likely with ligation procedures (22%), compared to surgical removal (1%) whether this was performed in the outpatient setting or operating theatre (OR 6.89 [95% CI 1.73, 27]). Parent-reported satisfaction was high for all treatments. Studies were at high risk of bias and low methodological quality. Outcome measurement and follow-up were heterogenous. Well-designed prospective observational and experimental studies are required to inform practice, incorporating clinician and parent-reported outcomes and economic analyses.
      Level of evidence: I.

      Keywords

      Introduction

      Ulnar (post-axial) polydactyly is a congenital upper limb anomaly characterised by the presence of an extra digit on the ulnar border of the hand at birth. Two distinct subtypes are recognised (Temtamy and MsKusick): type A, in which a fully developed extra digit articulates with either the fifth metacarpal or a duplicated metacarpal; or more commonly type B, a rudimentary non-functional digit that is attached by a soft tissue bridge.
      • Temtamy S.A.
      • McKusick V.A.
      The genetics of hand malformations.
      Approximately three quarters of cases of type B ulnar polydactyly are bilateral, and 85% have a family history.
      • Temtamy S.A.
      • McKusick V.A.
      The genetics of hand malformations.
      ,
      • Watson B.T.
      • Hennrikus W.L.
      Postaxial type-B polydactyly. Prevalence and treatment.
      The treatment of type B ulnar polydactyly is the removal of the non-functioning accessory digit, which carries a mild degree of functional disability, to restore a normal appearance of the hand.
      • Abzug J.M.
      • Kozin S.H.
      Treatment of postaxial polydactyly type B.
      ,
      • Chopan M.
      • Sayadi L.
      • Chim H.
      • Buchanan P.J.
      To tie or not to tie: a systematic review of postaxial polydactyly and outcomes of suture ligation versus surgical excision.
      The most effective treatment remains a topic of debate, and there is substantial variation in practice globally.
      • Chopan M.
      • Sayadi L.
      • Chim H.
      • Buchanan P.J.
      To tie or not to tie: a systematic review of postaxial polydactyly and outcomes of suture ligation versus surgical excision.
      Two treatments are most frequently reported: (1) suture/clip ligation
      • Watson B.T.
      • Hennrikus W.L.
      Postaxial type-B polydactyly. Prevalence and treatment.
      or (2) surgical excision.
      • Singer G.
      • Thein S.
      • Kraus T.
      • Petnehazy T.
      • Eberl R.
      • Schmidt B.
      Ulnar polydactyly - an analysis of appearance and postoperative outcome.
      ,
      • Carpenter C.L.
      • Cuellar T.A.
      • Friel M.T.
      Office-based post-axial polydactyly excision in neonates, infants, and children.
      Ligation involves tying off the base of the skin bridge with (typically) either a suture or metal clip, thereby inducing ischaemic necrosis and auto-amputation of the accessory digit. It is regarded as effective, well tolerated by patients and families and may avoid costs and complications associated with hospital admission and surgery under anaesthesia.
      • Watson B.T.
      • Hennrikus W.L.
      Postaxial type-B polydactyly. Prevalence and treatment.
      ,
      • Mills J.K.
      • Ezaki M.
      Ulnar polydactyly: long-term outcomes and cost-effectiveness of surgical clip application in the newborn.
      The disadvantages include a delay to autoamputation, a residual skin bridge that may be problematic in later life, risk of treatment failure and infection.
      • Watson B.T.
      • Hennrikus W.L.
      Postaxial type-B polydactyly. Prevalence and treatment.
      ,
      • Chopan M.
      • Sayadi L.
      • Chim H.
      • Buchanan P.J.
      To tie or not to tie: a systematic review of postaxial polydactyly and outcomes of suture ligation versus surgical excision.
      Surgical excision of the accessory digit may be performed in the outpatient clinic or operating theatre, under local or general anaesthesia depending on the age of the infant. Surgery may facilitate more proximal excision of accessory nerves, therefore, theoretically reducing the incidence of neuroma
      • Watson B.T.
      • Hennrikus W.L.
      Postaxial type-B polydactyly. Prevalence and treatment.
      ,
      • Rayan G.
      • Frey B.
      Ulnar polydactyly.
      and may improve the aesthetic outcome.
      • Mullick S.
      • Borschel G.H.
      A selective approach to treatment of ulnar polydactyly: preventing painful neuroma and incomplete excision.
      ,
      • Leber G.E.
      • Gosain A.K.
      Surgical excision of pedunculated supernumerary digits prevents traumatic amputation neuromas.
      Potential disadvantages include parental distress whilst awaiting treatment, need for general anaesthesia in older infants, and increased costs associated with hospital admission and an operative procedure.
      • Samra S.
      • Bourne D.
      • Beckett J.
      • Matthew M.
      Decision-making and management of ulnar polydactyly of the newborn: outcomes and satisfaction.
      One systematic review reports that complications are more prevalent following ligation compared with surgical excision; however, significant methodological flaws render their results unreliable.
      • Chopan M.
      • Sayadi L.
      • Chim H.
      • Buchanan P.J.
      To tie or not to tie: a systematic review of postaxial polydactyly and outcomes of suture ligation versus surgical excision.
      The aim of this systematic review is to compare the outcomes of suture ligation, office-based excision and operating room-based excision in type B ulnar polydactyly through a systematic appraisal of the literature.

      Methods

      The study was conducted in accordance with the Cochrane handbook for systematic reviews of interventions and was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The protocol was registered on Prospero (CRD42019156164).

      Search strategy

      The following databases were searched through the OVID search platform: (1) PubMed, (2) EMBASE, (3) PsycINFO, and (4) the Cochrane Library on October 30, 2019 to identify all articles reporting outcomes in primary interventions for type B ulnar polydactyly. See Supplementary Figure 1 for the search strategy in full.

      Study selection

      Studies that assessed outcomes following primary intervention for type B ulnar polydactyly were determined as eligible for inclusion. We included observational and experimental studies of any design. Case reports, review articles with no new primary data, and commentaries were excluded. Titles and abstracts were reviewed by two independent reviewers (LG and HS) against the inclusion and exclusion criteria, and discrepancies were resolved through discussion with a third independent reviewer (JW). The full texts of those considered to be potentially eligible for inclusion were reviewed by two independent reviewers against the inclusion/exclusion criteria. Any disagreements were resolved by discussion and review by a third independent reviewer.

      Data extraction

      Interventions have been grouped into the following three treatment methods: (1) Suture/clip ligation, (2) office based/minor treatment room excision and (3) operating room-based excision (under either local and general anaesthesia). A pre-piloted proforma was used to extract data from the studies that are included for analysis. The extracted information includes baseline characteristics, participant demographics and details of the intervention methods and study design. The outcomes for synthesis were as follows: (1) the prevalence of adverse events (clinician or parent-reported outcomes); (2) patient/parent satisfaction or ratings of appearance; (3) other clinician-assessed postoperative outcomes. Additional outcomes of interest include parent expressions of preference or motivation in treatment, local pathways, and influence of family history on decision-making.

      Risk of bias in individual studies

      The risk of bias was assessed using the risk of bias In Non-randomised Studies of Interventions (ROBINS-I) tool and presented using Robvis.
      • McGuinness L.A.
      • Higgins J.P.T.
      Risk-of-bias VISualization (robvis): an R package and Shiny web app for visualizing risk-of-bias assessments.
      Studies were assessed by two independent reviewers, and disagreements were resolved by discussion (HS/LG).

      Synthesis of results

      The pooled prevalence of complications was estimated using the metaprop package in Stata/MP v15. DerSimonian and Laird random effects were used given the clinical heterogeneity. The Freeman-Tukey arcsine transformation was used to stabilise the variance. However, 95% confidence intervals (CIs) around the study-specific and pooled prevalence were computed using the score-test statistic. Variations in the prevalence of complications were explored by meta-regression using metareg.
      • Harbord R.M.
      • Higgins J.P.T.
      Meta-regression in Stata.
      P-values were permuted with 20,000 iterations. Statistical heterogeneity was assessed by I2. A z-test (and the corresponding p-values) assessed whether the observed prevalence was different from zero per cent. To assess possible small-study effects (or publication bias across studies), we produced a funnel plot using metafunnel.

      Results

      Study selection

      After screening 1650 records, 15 studies
      • Watson B.T.
      • Hennrikus W.L.
      Postaxial type-B polydactyly. Prevalence and treatment.
      ,
      • Singer G.
      • Thein S.
      • Kraus T.
      • Petnehazy T.
      • Eberl R.
      • Schmidt B.
      Ulnar polydactyly - an analysis of appearance and postoperative outcome.
      ,
      • Macdonald C.R.
      • Kaur S.
      • Jester A.
      • Oestreich K.
      • Lester R.
      • Al-Ani S.A
      Office-based postaxial polydactyly excision in neonates, infants, and children.
      • Shirley R.
      • Pickford M.
      Local-anaesthetic day-case treatment of Stelling type 1 ulnar duplication in babies up to 4 months of age.
      • Stewart K.J.
      • Holmes J.D.
      • Kolhe P.S.
      Neonatal excision of minor congenital anomalies under local anaesthetic.
      • Khan P.
      • Hayat H.
      Surgical approach for treatment of pedunculated ulnar polydactyly: our experience.
      • Katz K.
      • Linder N.
      Postaxial type B polydactyly treated by excision in the neonatal nursery.
      ,
      • Carpenter C.L.
      • Cuellar T.A.
      • Friel M.T.
      Office-based post-axial polydactyly excision in neonates, infants, and children.
      • Mills J.K.
      • Ezaki M.
      Ulnar polydactyly: long-term outcomes and cost-effectiveness of surgical clip application in the newborn.
      • Rayan G.
      • Frey B.
      Ulnar polydactyly.
      • Mullick S.
      • Borschel G.H.
      A selective approach to treatment of ulnar polydactyly: preventing painful neuroma and incomplete excision.
      • Leber G.E.
      • Gosain A.K.
      Surgical excision of pedunculated supernumerary digits prevents traumatic amputation neuromas.
      • Samra S.
      • Bourne D.
      • Beckett J.
      • Matthew M.
      Decision-making and management of ulnar polydactyly of the newborn: outcomes and satisfaction.
      ,
      • Al Hassani F.
      • Nikkhah D.
      • Pickford M.A
      Correspondence and communications the management of ulnar polydactyly with a telemedicine-based referral system and a one-stop clinic.
      ,
      • Ahmad Z.
      • Park A.
      The milk anesthesia management of neonatal accessory digits: the 6 year coventry and warwickshire experience.
      were included (PRISMA flowchart, as shown Figure 1).

      Study characteristics

      The studies originated from different 5 countries (UK, USA, Israel, India and Austria; Table 1). All were cohort studies, three prospective
      • Watson B.T.
      • Hennrikus W.L.
      Postaxial type-B polydactyly. Prevalence and treatment.
      ,
      • Samra S.
      • Bourne D.
      • Beckett J.
      • Matthew M.
      Decision-making and management of ulnar polydactyly of the newborn: outcomes and satisfaction.
      ,
      • Katz K.
      • Linder N.
      Postaxial type B polydactyly treated by excision in the neonatal nursery.
      and 12 retrospective.
      • Singer G.
      • Thein S.
      • Kraus T.
      • Petnehazy T.
      • Eberl R.
      • Schmidt B.
      Ulnar polydactyly - an analysis of appearance and postoperative outcome.
      ,
      • Carpenter C.L.
      • Cuellar T.A.
      • Friel M.T.
      Office-based post-axial polydactyly excision in neonates, infants, and children.
      ,
      • Stewart K.J.
      • Holmes J.D.
      • Kolhe P.S.
      Neonatal excision of minor congenital anomalies under local anaesthetic.
      ,
      • Khan P.
      • Hayat H.
      Surgical approach for treatment of pedunculated ulnar polydactyly: our experience.
      ,
      • Mills J.K.
      • Ezaki M.
      Ulnar polydactyly: long-term outcomes and cost-effectiveness of surgical clip application in the newborn.
      • Rayan G.
      • Frey B.
      Ulnar polydactyly.
      • Mullick S.
      • Borschel G.H.
      A selective approach to treatment of ulnar polydactyly: preventing painful neuroma and incomplete excision.
      • Leber G.E.
      • Gosain A.K.
      Surgical excision of pedunculated supernumerary digits prevents traumatic amputation neuromas.
      ,
      • Al Hassani F.
      • Nikkhah D.
      • Pickford M.A
      Correspondence and communications the management of ulnar polydactyly with a telemedicine-based referral system and a one-stop clinic.
      • Ahmad Z.
      • Park A.
      The milk anesthesia management of neonatal accessory digits: the 6 year coventry and warwickshire experience.
      • Macdonald C.R.
      • Kaur S.
      • Jester A.
      • Oestreich K.
      • Lester R.
      • Al-Ani S.A
      Office-based postaxial polydactyly excision in neonates, infants, and children.
      • Shirley R.
      • Pickford M.
      Local-anaesthetic day-case treatment of Stelling type 1 ulnar duplication in babies up to 4 months of age.
      There were two multi-arm studies
      • Rayan G.
      • Frey B.
      Ulnar polydactyly.
      ,
      • Samra S.
      • Bourne D.
      • Beckett J.
      • Matthew M.
      Decision-making and management of ulnar polydactyly of the newborn: outcomes and satisfaction.
      whilst the remainder was single-arm studies. Across all studies, interventions to remove the accessory digit were performed from 2 days of age
      • Katz K.
      • Linder N.
      Postaxial type B polydactyly treated by excision in the neonatal nursery.
      up to a maximum of 4.2 years
      • Carpenter C.L.
      • Cuellar T.A.
      • Friel M.T.
      Office-based post-axial polydactyly excision in neonates, infants, and children.
      with an average age of 96 days. Revisional procedures were performed up to a maximum age of 13 years.
      • Mullick S.
      • Borschel G.H.
      A selective approach to treatment of ulnar polydactyly: preventing painful neuroma and incomplete excision.
      Age of intervention varied with treatments, with ligation performed from 1 week
      • Watson B.T.
      • Hennrikus W.L.
      Postaxial type-B polydactyly. Prevalence and treatment.
      to 40 weeks of age,
      • Mills J.K.
      • Ezaki M.
      Ulnar polydactyly: long-term outcomes and cost-effectiveness of surgical clip application in the newborn.
      clinic-based excision from 2 days
      • Katz K.
      • Linder N.
      Postaxial type B polydactyly treated by excision in the neonatal nursery.
      to 4.2 years
      • Carpenter C.L.
      • Cuellar T.A.
      • Friel M.T.
      Office-based post-axial polydactyly excision in neonates, infants, and children.
      and OR-based excision from 3 days
      • Stewart K.J.
      • Holmes J.D.
      • Kolhe P.S.
      Neonatal excision of minor congenital anomalies under local anaesthetic.
      to 36 months.
      • Khan P.
      • Hayat H.
      Surgical approach for treatment of pedunculated ulnar polydactyly: our experience.
      Where reported, the male/female ratio was 1.3:1 (Table 2).
      Table 1Study design and characteristics.
      Author (date)LocationStudy designParticipantsStudy sizeDigitsAge at interventionM:F ratioPrevious interventionProcedure
      Ligation
      Watson & Henrikus (1997)USAProspective case seriesType B (T&M)2137(1–2 weeks)12:9NoneSuture ligation in neonatal nursery
      Mills (2014)USARetrospective case seriesType B (T&M) base of digit < 6mm1322318 weeks (2–40 weeks)77:55NoneOPD clip application with LA
      Clinic-based excision
      Katz (2011)IsraelProspective case seriesType B (T&M)1115(2–3 days)6:5NoneLA excision, neonatal minor ops room
      Carpenter (2015)USARetrospective case seriesType B (T&M)26383.3months (9 days - 4.2 years)NR5 patients had previous suture ligation, now being treated for residual bumpLA excision, office-based
      Al Hassani (2019)UKRetrospective case seriesStelling I284369 Days (27–134)14:16NoneLA excision in paediatric minor treatment unit
      Operating theatre-based excision
      Stewart (2001)UKRetrospective case series‘Minor forms’ of U.P.40NR3 days (1–14 days)NRNoneLA surgical excision
      Leber (2003)USARetrospective case seriesPedunculated supernumerary digits611(3 weeks – 21 months)3:3noneSurgical excision
      Mullick (2010)USARetrospective case seriesType B (T&M)1013(1 week – 13 years)5:5All presented with incomplete amputations, painful neuroma or both – prev. ligationGA surgical excision
      Khan (2012)IndiaRetrospective case seriesStelling IIa UP102018.2 months (6–36 months)5:5NoneGA surgical excision
      Ahmad (2014)UKRetrospective case seriesType B (T&M)86135(<10 weeks)NRNoneLA surgical excision
      Singer (2014)AustriaRetrospective case seriesStelling I/II/III32418.6 months (0–10months)NRNRGA surgical excision
      Macdonald (2017)UKRetrospective case seriesType B (T&M)20NR(< 6 weeks)NRNoneLA surgical excision
      Shirley (2019)UKRetrospective case seriesStelling I4058(3 – 18 weeks)NRNoneLA surgical excision
      Comparative studies
      Rayan (2000)USARetrospective cohort studyAll types UP (82% Stelling I/II)122123NR85:63NoneSuture ligation

      Surgical excision

      No treatment
      Samra (2016)USAProspective cohort studyType B (T&M)1425NRNRNoneSuture ligation

      LA excision in clinic,

      GA excision in OR
      Table 2Adverse events and patient-reported outcomes.
      AuthorAdmission (Y/N/NR)FU periodOverall complicationTreatment failureNeuromaNubbin

      Unaesthetic scar
      Revision procedureParent reported outcomes
      Ligation
      Watson & Henrikus (1997)N1–2 weeks, then 15/21 patients at 20 months57.1%4.7%NR52.4%4.7%No parent reported outcomes
      Rayan (2000)

      LIGATION N = 105
      NR1–2 weeks (some at 12–37 months)23.5%NR6.7%16.1%2.8%No parent reported outcomes
      Mills (2014)NR10–14 days10.7%NR7%3.7%7%No parent reported outcomes
      Samra (2016)

      LIGATION N = 2
      NR1 month and 3 months0%NRNRNRNR0 – 10 satisfaction score

      10

      Higher perceived pain 5/10
      Clinic-based excision
      Katz (2011)NRPost-op Day 1, 1 week, 1 year0%0%NR0%0%‘All expressed satisfaction with cosmetic result’
      Carpenter (2015)NNR7.7%NRNRNRNRNo parent reported outcomes
      Samra (2016)

      LA Excision

      N = 10
      NR1 month and 3 months0%NRNRNRNR9.8/10 satisfaction score
      Al Hassani (2019)NTelephone questionnaireNRNRNRNRNR100% rated scar as excellent.

      24 would recommend, 4 would not
      Operating theatre-based excision
      Rayan (2000)

      EXCISION N = 27
      NR1–2 weeks (some at 12–37 months)3.7%NR3.7%0%0%No parent reported outcomes
      Stewart (2001)NRNoneNRNRNRNRNRHigh levels of satisfaction

      39/40 felt that scar barely noticeable
      Leber (2003)NRUp to 6 years0%NRNRNR0All were pleased with cosmetic result
      Mullick (2010)NR1–3 months post-op00000Cosmetic outcome - All regarded ‘Acceptable’ to parents + surgeon
      Khan (2012)NR2 years10% (infection)0000No parent reported outcomes
      Ahmad (2014)NRNone2.2%0%0%1.1%0%’Parents of patients were very pleased by the overall service’
      Singer (2014)NRQuestionnaire FU years later10%0(5%) of nubbins10%NRVAS 1–100 for function – score 89/100
      SAMRA (2016)

      GA Excision

      N = 2
      NR1 month and 3 months1 month and 3 months0%NRNRNRNR10/10 satisfaction score

      Both did describe emotional distress (6/10) with having to wait
      Macdonald (2017)NTelephone FU, 20 received formal surveyNRNRNRNRNR19/20 very high overall satisfaction. 18/20 for scar
      Shirley (2019)NTelephone questionnaire5%NRNR5%NRNo parent reported outcomes

      Risk of bias assessment

      The risk of bias was high across included studies. Common limitations include non-consecutive inclusion of patients, incomplete or selective follow-up (with 6 studies not providing follow-up at all) and a lack of systematic analysis of outcomes. A total of 13 out of 15 included studies are case series, in which bias is inherent in participant selection, absence of comparators and retrospective reviews of notes. A more detailed breakdown of risk as determined by the ROBINS-I tool is provided in Figure 2.
      Figure 2
      Figure 2The summary risk of bias plot for included studies. Red = high risk; yellow = unclear risk; green = low risk.

      Adverse events

      The pooled prevalence of complications was 6.0% (95% CI 1, 13; Figure 3). Complications were more common following ligation procedures (22.0% [95% CI 5, 44]; I2 87%) compared to surgical excision in the outpatient setting (1.0% [95% CI 0, 8]) or operating theatre (1.0% [95% CI 0, 4] I2 0%), although there was significant heterogeneity overall (I2 74%).
      Figure 3
      Figure 3Forest plot showing the prevalence (%) of complications and 95% CIs. Estimates by pooled according to the method used to remove the accessory digit.
      Meta-regression showed that ligation was associated with 6 times the odds of complications (OR 6.89 [95% CI 1.73, 27] p = 0.013; permuted p = 0.012) when compared with surgical excision in either a theatre or the outpatient setting. Performing the procedure in an operating theatre did not reduce the risk of complications as compared to the outpatient clinic (OR 3.75 [95% CI 0.66, 21] p = 0.114).
      A funnel plot of the risk of complications against study precision showed that datapoints were strongly asymmetrical (Figure 4; Egger's regression co-efficient 0.80 [95% CI −0.69, 2.29], p = 0.246; Figure 4), which suggests the presence of small-study effects (publication bias).
      Figure 4
      Figure 4Funnel plot suggesting the presence of small-study effects (publication bias).

      Patient (parent)-reported measures

      There was insufficient data for a meta-analysis of patient-reported outcomes. Such data were available in one multi-arm study
      • Samra S.
      • Bourne D.
      • Beckett J.
      • Matthew M.
      Decision-making and management of ulnar polydactyly of the newborn: outcomes and satisfaction.
      and four single-arm studies, and none were recognised validated measures. Samra et al. report no difference in overall satisfaction between ligation and excision groups; however, they note that infants’ perceived pain scores were higher in the suture ligation group, whilst emotional distress was higher for parents choosing excision under GA, which they attributed to the delay to intervention.
      • Samra S.
      • Bourne D.
      • Beckett J.
      • Matthew M.
      Decision-making and management of ulnar polydactyly of the newborn: outcomes and satisfaction.
      Parental ratings of scar/cosmesis were assessed in 4 single-arm studies, and the scores were consistently high.
      • Singer G.
      • Thein S.
      • Kraus T.
      • Petnehazy T.
      • Eberl R.
      • Schmidt B.
      Ulnar polydactyly - an analysis of appearance and postoperative outcome.
      ,
      • Carpenter C.L.
      • Cuellar T.A.
      • Friel M.T.
      Office-based post-axial polydactyly excision in neonates, infants, and children.
      ,
      • Al Hassani F.
      • Nikkhah D.
      • Pickford M.A
      Correspondence and communications the management of ulnar polydactyly with a telemedicine-based referral system and a one-stop clinic.
      ,
      • Stewart K.J.
      • Holmes J.D.
      • Kolhe P.S.
      Neonatal excision of minor congenital anomalies under local anaesthetic.

      Discussion

      This systematic review and metanalysis demonstrate a paucity of high-quality studies. The available evidence suggests that suture ligation carries a clinically and statistically significant higher risk of complications than surgical excision. Studies to date suggest a higher risk of aesthetically unacceptable remnant nubbins with suture/clip ligation, compared to excision
      • Watson B.T.
      • Hennrikus W.L.
      Postaxial type-B polydactyly. Prevalence and treatment.
      ,
      • Rayan G.
      • Frey B.
      Ulnar polydactyly.
      ; however, the reliability of this observation is questionable due to a general lack of standardised outcome measurement and follow-up across the included studies. For example, between 2.8 and 7.0% of parents requested revisional procedures for remnant nubbins, suggesting they may not be as important to parents and patients as surgeons believe.
      • Watson B.T.
      • Hennrikus W.L.
      Postaxial type-B polydactyly. Prevalence and treatment.
      ,
      • Mills J.K.
      • Ezaki M.
      Ulnar polydactyly: long-term outcomes and cost-effectiveness of surgical clip application in the newborn.
      ,
      • Rayan G.
      • Frey B.
      Ulnar polydactyly.
      A digital neuroma is infrequently assessed, though one study suggests a higher incidence after suture ligation (6.7%), compared with excision (3.7%)
      • Rayan G.
      • Frey B.
      Ulnar polydactyly.
      ; however, there is insufficient data on rates of revisional surgery.
      Clinic-based and operating theatre-based excision should be recognised as distinct modalities owing to procedural differences and, in some cases, implications for anaesthesia and admission. This review finds comparable rates of adverse outcomes which suggests that some of the purported disadvantages of surgical excision that relate to treatment delay, distress due to perceived stigma and concern relating to general anaesthesia may be circumvented through clinic-based excision.
      • Samra S.
      • Bourne D.
      • Beckett J.
      • Matthew M.
      Decision-making and management of ulnar polydactyly of the newborn: outcomes and satisfaction.
      ,
      • Shirley R.
      • Pickford M.
      Local-anaesthetic day-case treatment of Stelling type 1 ulnar duplication in babies up to 4 months of age.
      The approach is best tolerated in younger infants, and well-established pathways for referral are key to timely delivery.
      • Al Hassani F.
      • Nikkhah D.
      • Pickford M.A
      Correspondence and communications the management of ulnar polydactyly with a telemedicine-based referral system and a one-stop clinic.
      Theatre-based local anaesthetic excision shares these advantages but comes with greater cost and resource consumption for services.
      Our review shows a paucity of the patient and parent voice in current research, with only 5 studies evaluating this using archaic instruments. A postoperative questionnaire delivered by Samra et al.
      • Samra S.
      • Bourne D.
      • Beckett J.
      • Matthew M.
      Decision-making and management of ulnar polydactyly of the newborn: outcomes and satisfaction.
      showed that parental satisfaction was high in all three treatment arms, despite differences in specific measures such as pain scores and satisfaction with cosmetic appearance. Some studies suggest that the timing of treatment is of paramount importance to parents. Shirley et al. commented that parents often express dissatisfaction with the stigma of accessory digits,
      • Shirley R.
      • Pickford M.
      Local-anaesthetic day-case treatment of Stelling type 1 ulnar duplication in babies up to 4 months of age.
      and Stewart et al. ascribed the high satisfaction (39/40) rates in their study (LA excision at a median age of 3 days) to early treatment.
      • Stewart K.J.
      • Holmes J.D.
      • Kolhe P.S.
      Neonatal excision of minor congenital anomalies under local anaesthetic.
      Parent views on anaesthetic choice are also significant and not explored in the published literature.
      Validated outcome measures may improve our assessment of both objective surgical outcomes, such as scar quality and patient/parent-reported outcomes, such as overall satisfaction with treatment and appearance.
      • Bickham R.S.
      • Waljee J.F.
      • Chung K.C.
      • Adkinson J.M.
      Postoperative patient- and parent-reported outcomes for children with congenital hand differences: a systematic review.
      To ensure optimal impact and relevance to patients, future comparative studies should select patient- or parent-centred primary endpoints. Patient and public involvement is an integral to this aim, specifically, in devising pertinent research questions and selecting impactful study outcomes.
      • Crocker J.C.
      • Pratt-Boyden K.
      • Hislop J.
      • et al.
      Patient and public involvement (PPI) in UK surgical trials: a survey and focus groups with stakeholders to identify practices, views, and experiences.
      Future study design should consider that, given the strong genetic component in type B ulnar polydactyly, parental perspective may in many cases be shaped by personal experience of treatment and complications.
      • Leber G.E.
      • Gosain A.K.
      Surgical excision of pedunculated supernumerary digits prevents traumatic amputation neuromas.
      ,
      • Ahmad Z.
      • Park A.
      The milk anesthesia management of neonatal accessory digits: the 6 year coventry and warwickshire experience.
      Future studies should also consider the cost and benefits of proposed treatments. Excision under general anaesthesia is associated with increased costs. One study estimates that excision incurs a 40-fold increase in costs when compared to office-based clip application.
      • Mills J.K.
      • Ezaki M.
      Ulnar polydactyly: long-term outcomes and cost-effectiveness of surgical clip application in the newborn.
      Office-based excision may also offer comparative savings to services. Al-Hassani et al. reported a decrease in procedure time from 59 min in the OR to 18 min.
      • Al Hassani F.
      • Nikkhah D.
      • Pickford M.A
      Correspondence and communications the management of ulnar polydactyly with a telemedicine-based referral system and a one-stop clinic.
      This finding is not consistent across studies, however, with one study reporting operating time for local anaesthetic treatment to be 19 min.
      • Shirley R.
      • Pickford M.
      Local-anaesthetic day-case treatment of Stelling type 1 ulnar duplication in babies up to 4 months of age.
      The optimum management of type B ulnar polydactyly is unclear based on the available evidence. Furthermore, prior studies have not been designed with patient or public involvement. There is a pressing need for a prospective observational or experimental study assessing the benefits and drawbacks of different treatment options and their cost-efficacy in the modern health service, with all relevant stakeholders involved.

      Ethical approval declaration

      Ethical approval was not sought for this review.

      CRediT authorship contribution statement

      Harsh Samarendra: Conceptualization, Formal analysis, Data curation, Investigation, Software, Writing – review & editing. Ryckie G. Wade: Conceptualization, Formal analysis, Data curation, Investigation, Software, Writing – review & editing. Louise Glanvill: Conceptualization, Formal analysis, Data curation, Investigation, Software, Writing – review & editing. Justin Wormald: Conceptualization, Formal analysis, Writing – review & editing. Abhilash Jain: Conceptualization, Formal analysis, Writing – review & editing.

      Declaration of Competing Interest

      The author(s) declare no potential competing of interest with respect to the research, authorship and/or publication of this article.

      Funding

      This work was supported by a grant (Grant code: HFR03580) from the British Society for Surgery of the Hand.

      Appendix. Supplementary materials

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