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The never-ending battle between proximal row carpectomy and four corner arthrodesis: A systematic review and meta-analysis for the final verdict

Open AccessPublished:October 23, 2021DOI:https://doi.org/10.1016/j.bjps.2021.09.076

      Summary

      While scaphoid excision combined with Four Corner Arthrodesis (FCA) or Proximal Row Carpectomy (PRC) is a commonly-used salvage procedures to treat type two and type three Scapholunate Advanced Collapse (SLAC) and Scaphoid Nonunion Advanced Collapse (SNAC)-induced degenerative arthritis, controversy remains over which treatment intervention provides superior outcomes. We searched for articles comparing a range of motion, grip strength, complications requiring reoperation, conversion to wrist arthrodesis, pain, and disability of shoulder and arm scores between FCA and PRC-treated patients. The risk of bias was assessed using the National Institutes of Health (NIH) quality assessment tool. We performed a meta-analysis using Random-Effects Models. Fifteen articles (10 retrospective, 2 cross-sectional, 1 prospective, and 2 randomized trials) were included. There was no significant difference between PRC and FCA in any of the different outcome measures. The risk of bias was found consistently high across all studies. Despite the lack of high-quality evidence, based on existing literature, we recommend PRC as the preferred choice of treatment because of the simplicity of the surgical procedure, lack of hardware-related complications, and comparable long-term outcomes.
      Level of evidence: III - Therapeutic

      Keywords

      Introduction

      The human wrist is a complex formation with interactions between several small bones and interligamentary connections resulting in a mobile and stable hand function. If left untreated, disruption of this complex anatomical formation can result in degenerative arthritis, severe pain, and eventually progressive loss of hand function. Degenerative wrist arthritis can arise from rheumatoid arthritis or posttraumatic arthritis affecting the radiocarpal and midcarpal joints of the wrist. The scaphoid bone is an important anatomical and junctional link between the proximal and distal carpal bones.
      Scapholunate advanced collapse (SLAC) and scaphoid nonunion advanced collapse (SNAC) are the two most common patterns of degenerative wrist arthritis. In 1984, Watson and Ballet first described SLAC as the most common form of degenerative wrist arthritis.
      • Watson H.K.
      • Ballet F.L.
      The SLAC wrist: scapholunate advanced collapse pattern of degenerative arthritis.
      This condition can be attributed to spontaneous osteoarthritis or post-traumatic injury of the wrist. Due to the abnormal distribution of forces across midcarpal and radiocarpal joints, the radioscaphoid joint is affected, which can progress to the capitolunate joint (Figure 1A). SNAC, a condition of advanced collapse and progressive arthritis of the wrist, results from a chronic scaphoid nonunion, mainly originating from traumatic injury (Figure 1B).
      Figure 1
      Figure 1A. SLAC & SNAC Degenerative Arthritis. This image displays the different stages of SLAC and the affected joints and carpal bones. Stage 1: Degenerative changes of the styloid tip of the radius. Stage 2: Degenerative changes progress to the radioscaphoid joint. Progressive joint space narrowing and sclerosis are indicative of this stage*#. Stage 3: Degenerative changes progress to the capitolunate joint#. Stage 4: Degenerative changes affect the radiocarpal and intercarpal articulations§. *PRC Indication #FCA Indication §TWA Indication. B. SNAC Wrist. This image displays the different stages of SNAC and the affected joints and carpal bones. Stage 1: Degenerative changes of the radial side of the scaphoid and radial styloid. Stage 2: Degenerative changes progress to the scaphocapitatearticulation*#. Stage 3: Degenerative changes progress to the periscaphoid including the capitolunate articulation#. Stage 4: Degenerative changes affect the radiocarpal and intercarpal articulations§. *PRC Indication #FCA Indication §TWA Indication
      When conservative treatment fails, surgical interventions are indicated. Ideal surgical treatment should result in pain relief and good wrist functionality. Currently, no curative therapies exist; however, many treatment options have been developed for symptomatic relief. Traditionally, end-stage SLAC and SNAC arthritis were treated with total wrist arthrodesis (TWA). Although TWA leads to pain relief in most cases, wrist motion is sacrificed. TWA is currently considered a salvage procedure when other therapies fail. However, newer alternatives to TWA include the use of motion sparing arthroplasty implants which are more anatomically aligned, require minimal bone resection, and offer an improved range of motion and grip strength.
      • Halim A.
      • Weiss A.C.
      Total wrist arthroplasty.
      Proximal Row Carpectomy (PRC) and Four Corner Arthrodesis (FCA) are the two most common surgical procedures to treat SLAC and SNAC wrists. These treatment modalities are preferred because they address pain and simultaneously preserve ROM. Briefly, PRC is a resection of the proximal carpal row consisting of the scaphoid, lunate, and triquetrum bones. PRC allows the capitate bone to articulate with the lunate facet of the distal radius, creating a new joint formation (Figure 2A). FCA is a resection of the scaphoid bone and arthrodesis between the lunate, capitate, hamate, and triquetrum bones. This procedure aims to fuse the arthritic midcarpal joint and to reduce pressure in the scaphoid fossa, by redistributing the cartilage contact areas to the lunate fossa. FCA can be performed traditionally with screw fixation (Figure 2B) or with a circular plate (Figure 2C) which is used as an alternative fixation method, preferred by few surgeons in comparison to the traditional compression screws. The rationale for both procedures is the redistribution of the force from the scaphoid fossa to the lunate fossa cartilage of the radius since this cartilage is not affected by the degenerative changes. This lunate fossa is spared from degenerative changes as it is protected from incongruent pressure by its tight ligamentous structures, which control a near spherical joint profile with the capitate base. However, it is not more resilient against arthritic changes than other structures in the wrist and can feature in advanced-stage disease. Indications for the use of each operative procedure are listed in Figures 1 and 2. Generally, FCA is essential, if there is midcarpalosteoarthrtitis and the capitolunate joint is affected in the SLAC or SNAC wrist. A disadvantage for choosing PRC might be an incongruity between the capitate and the lunate fossa leading to degenerative changes and pain and eventually to TWA. However, controversy persists over which of the two procedures has the superior functional short-term and long-term outcome. Two systematic reviews have been published on this topic in 2009 and 2015.
      • Saltzman B.M.
      • Frank J.M.
      • Slikker W.
      • Fernandez J.J.
      • Cohen M.S.
      • Wysocki R.W.
      Clinical outcomes of proximal row carpectomy versus four-corner arthrodesis for post-traumatic wrist arthropathy: a systematic review.
      ,
      • Mulford J.S.
      • Ceulemans L.J.
      • Nam D.
      • Axelrod T.S.
      Proximal row carpectomy vs four-corner fusion for scapholunate (SLAC) or scaphoid nonunion advanced collapse (SNAC) wrists: a systematic review of outcomes.
      Only Mulford et al. conducted a meta-analysis but on subjective outcomes, the relative risk of postoperative conversion, and post-operative osteoarthritic changes.
      • Mulford J.S.
      • Ceulemans L.J.
      • Nam D.
      • Axelrod T.S.
      Proximal row carpectomy vs four-corner fusion for scapholunate (SLAC) or scaphoid nonunion advanced collapse (SNAC) wrists: a systematic review of outcomes.
      Our study, on the contrary, presents the most up-to-date systematic review and meta-analysis on the most important postoperative outcome measures to help guide clinicians in patient selection and preferred operative method and patients in their treatment choice.
      Figure 2
      Figure 2A. PRC operative procedure. The left figure shows the PRC procedure, whereby the proximal row consisting of the scaphoid, lunate and triquetrum (translucent) will be removed. The figure on the right, shows the post-operative situation. The capitate bone will move down and articulate with the lunate facet of the distal radius, creating a new joint formation (pink highlighted area). Therefore, it is paramount that the capito-lunate articulation is intact and free of osteoarthritic changes for a PRC to work. B. FCA operative procedure with screws. Shown here is the dorsal view of the hand. The scaphoid bone (S) is resected and removed whilst the lunate (L), capitate (C), hamate (H) and triquetrum (T) carpal bones are fused together with compression screws. C: FCA Operative Procedure with Circular Plate. Shown here is the dorsal view of the hand. The scaphoid bone (S) is resected and removed whilst the lunate (L), capitate (C), hamate (H) and triquetrum (T) carpal bones are fused together with a circular plate instead of screws. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article)

      Methods

      The study was designed according to the Cochrane Handbook for Interventional Systematic Reviews and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P).
      • Moher D.
      • Shamseer L.
      • Clarke M.
      • et al.
      Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015 statement.

      Literature search strategy

      Comprehensive searches were carried out in Embase, Medline, Pubmed Publisher, Web-of Science, OvidSP, Cochrane Central Register of Controlled Trials (The Cochrane Library, December 2019, issue 12 of 12), and Google Scholar databases for articles published up to December 2019 by using keywords specific to each search engine (Text S1).

      Inclusion and exclusion criteria

      The main inclusion criteria were studies evaluating one or more of the following postoperative outcomes of PRC and/or FCA for the treatment of SLAC and SNAC wrists: range of motion (ROM), grip strength, complications leading to reoperations, conversion to TWA, Visual Analog Scale (VAS) pain or Disability of the Arm, Shoulder, and Hand Questionnaire (DASH) scores. Only full-text, original articles written in English were considered for inclusion in the study. Studies combining limited 2 or 3 corners with 4 corner arthrodesis versus PRC were excluded. All reviews, conference abstracts, book chapters, letters, case series, and editorials were excluded.

      Literature screening

      Relevance and inclusion of the articles were screened by two individual researchers (ARA, LSD) who also screened titles, keywords, and abstracts of all considered articles, according to the pre-established criteria. In case of discrepancy, a third author (JMZ) was consulted. After inclusion based on the above parameters, full-text articles were retrieved and reviewed for inclusion. All articles were evaluated using the PICO (Patient/Problem, Intervention, Comparison, Outcomes) method. All included articles were rated for their level of evidence according to an adapted version from material published by the Center for Evidence-Based Medicine, Oxford, UK.

      OCEBM Working Group. The Oxford 2011 Levels of Evidence. Oxford centre for evidence-based medicine. 2011; http://www.cebm.net/ocebm-levels-of-evidence/.

      Risk of bias assessment

      The risk of bias assessment for observational cohort and cross-sectional studies and intervention studies was carried out by two authors (ARA, LSD) using the National Institutes of Health (NIH) study quality assessment tool.

      National Institutes of Health (NIH). Study Quality Assessment Tools. https://www.nhlbi.nih.gov/health-topics/study-quality-assessment-tools. Accessed 28-05-2020).

      Statistical analysis

      We performed a meta-analysis on the following parameters: ROM, grip strength, complications, conversions to total arthrodesis, VAS pain score, and DASH score. When standard deviations were not reported, we calculated them based on the method described by Hozo et al.
      • Hozo S.P.
      • Djulbegovic B.
      • Hozo I.
      Estimating the mean and variance from the median, range, and the size of a sample.
      . For continuous outcomes, we performed a meta-analysis using a random-effects model to estimate the pooled mean difference and 95% confidence interval (CI). For dichotomous data, we used the random-effects model to estimate the pooled risk difference. We tested whether the type of surgery influenced the pooled means or proportions by adding the type of surgery as an independent variable and whether the patient characteristics were the same for both types of surgery.
      The Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines were followed. A P-value < 0.05 was deemed statistically significant. All analyses were performed with R version 3.6.0 and the Metafor package.
      • Viechtbauer W.
      Conducting meta-analyses in R with the metafor package.

      Results

      Study demographics

      In total, 1619 articles were retrieved and subjected to screening based on the inclusion and exclusion criteria. Only 16 studies met the initial scope of our study (Figure S1). Upon reading the full text, one article was excluded because it only reported outcomes of two and four corner fusions combined. Of the remaining 15 studies, ten were retrospective (Level III), two cross-sectional (Level III-IV), one prospective cohort (Level II), and two randomized controlled trials (RCTs, Level I) (Figure 3A). The minimum number of included patients per study was 20, with a maximum number of 123 patients. The two RCTs had 20 and 26 patients. Despite the differences in the level of evidence due to the study design, all studies were included in the meta-analyses.
      Figure 3
      Figure 3A. Study Demographic I. Four Corner Arthordesis (FCA), Proximal Row Carpectomy (PRC), Scapholunate Collaps (SLAC), Scaphoid Nonunion (SNAC), Randomized Controlled Trial (RCT), Not Available (NA), Numbers between parentheses represent (standard deviation/range). B. Study Demographic II. Four Corner Arthordesis (FCA), Proximal Row Carpectomy (PRC), Scapholunate Collaps (SLAC), Scaphoid Nonunion (SNAC), Dominant/Nondominant Operated Wrist (Dom/Nondom), Follow-up (FU), Not Available (NA), Numbers between parenthesis represent (standard deviation/range).
      In total, 322 FCA and 328 PRC-treated patients were included in the analysis with the mean age of 48 years in the FCA group and 46 in the PRC group (Figure 3B). Mean follow-up ranged from 6 months to 18 years across the studies. The mean follow-up time across all studies was 5.1 years in the FCA and 5.3 years in the PRC group. In the FCA group, 77% were males and 23% females and in the PRC group, 68% were males and 32% females.
      Only nine studies reported the number of treated SLAC and SNAC wrists by either PRC or FCA. The majority of the studies included patients with a grade II/III SLAC/SNAC diagnosis. Of the eight studies, two also included patients with SLAC/SNAC grade I. The remaining seven studies did not report on the SLAC/SNAC grading. All studies except three reported on whether the dominant hand was operated. Only seven studies reported on the number of surgeons that operated, and 10 out of 15 studies mentioned the professional who registered outcome measurements and performed additional testing or collected clinical data. The majority of the studies cited using independent observers (5/15), occupational therapists (3/15), and research staff (2/15).

      Risk of bias

      The risk of bias was evaluated with the NIH tool. The majority of studies were at serious risk due to a poorly defined and specified study population and in some cases from two different countries and different institutions, and the lack of specific inclusion and exclusion criteria (Figure 4). Almost all studies lacked sample size justification, power analysis, or proper statistical methods to adjust for confounders. Outcome measurements were not conducted in a blinded setting in any study.
      Figure 4
      Figure 4Risk of Bias. Risk of bias assessed by the NIH study quality assessment tool. Yes (Y), No (N), Not Applicable (NA), Could not Determine (CD). The green color is associated with low risk and red color with a high risk of bias. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article).

      Active ROM outcomes

      In total, 13/15 studies reported on the ROM. Separate extension, flexion, radial deviation, and ulnar deviation values were reported in eight studies. Three of them were excluded from the pooled analysis because of missing SD or statistical analysis.;pl[-5666666666666666 gftr1
      • Wyrick J.D.
      • Stern P.J.
      • Kiefhaber T.R.
      Motion-preserving procedures in the treatment of scapholunate advanced collapse wrist: proximal row carpectomy versus four-corner arthrodesis.
      • Krakauer J.D.
      • Bishop A.T.
      • Cooney W.P.
      Surgical treatment of scapholunate advanced collapse.
      • Bisneto E.N.
      • Freitas M.C.
      • Paula E.J.
      • Mattar R.
      • Zumiotti A.V.
      Comparison between proximal row carpectomy and four-corner fusion for treating osteoarthrosis following carpal trauma: a prospective randomized study.
      In the meta-analysis, we found no significant differences between PRC and FCA in extension -9.35° (-30.72°–12.02°), P = 0.29, I2 = 96%; flexion -5.89° (-17.24°– 5.47°), P = 0.22, I2 = 91%; radial 4.74° (-3.56°–13.03°), P = 0.19, I2 = 94%; or ulnar deviation -2.52° (-10.02°– 4.98°), P = 0.40, I2 = 76%. (Figure 5). High heterogeneity was noted among the studies in all motion exercises (P < 0.01).
      Figure 5
      Figure 5Range of Motion. This figure shows the mean difference in ROM between FCA and PRC and the estimated 95% CI of this difference using a Random Effects Model. The lowest diamond is the pooled mean difference of all studies. A negative value indicates that the FCA group had a smaller ROM than the PRC group.
      Five studies were excluded from the meta-analysis because they reported only either a combined extension/flexion arc
      • Dacho A.K.
      • Baumeister S.
      • Germann G.
      • Sauerbier M.
      Comparison of proximal row carpectomy and midcarpal arthrodesis for the treatment of scaphoid nonunion advanced collapse (SNAC-wrist) and scapholunate advanced collapse (SLAC-wrist) in stage II.
      or a combined radial/ulnar deviation arc
      • Singh H.P.
      • Bhattacharjee D.
      • Dias J.J.
      • Trail I.
      Dynamic assessment of the wrist after total wrist arthroplasty.
      ,
      • Wolff A.L.
      • Garg R.
      • Kraszewski A.P.
      • et al.
      Surgical treatments for scapholunate advanced collapse wrist: kinematics and functional performance.
      or only the total arc of motion.
      • Aita M.A.
      • Nakano E.K.
      • Schaffhausser H.L.
      • Fukushima W.Y.
      • Fujiki E.N.
      Randomized clinical trial between proximal row carpectomy and the four-corner fusion for patients with stage II SNAC.
      Three studies reported on a combined extension/flexion and radial/ulnar deviation arc between PRC and FCA, but no significant differences were observed.
      • Dacho A.K.
      • Baumeister S.
      • Germann G.
      • Sauerbier M.
      Comparison of proximal row carpectomy and midcarpal arthrodesis for the treatment of scaphoid nonunion advanced collapse (SNAC-wrist) and scapholunate advanced collapse (SLAC-wrist) in stage II.
      • Singh H.P.
      • Bhattacharjee D.
      • Dias J.J.
      • Trail I.
      Dynamic assessment of the wrist after total wrist arthroplasty.
      • Wolff A.L.
      • Garg R.
      • Kraszewski A.P.
      • et al.
      Surgical treatments for scapholunate advanced collapse wrist: kinematics and functional performance.
      One study reported on the extension/flexion arc, which was significantly improved in PRC 73 ± 5 compared to FCA 54 ± 6, P < 0.01.
      • Wagner E.R.
      • Werthel J.D.
      • Elhassan B.T.
      • Moran S.L.
      Proximal row carpectomy and 4-corner arthrodesis in patients younger than age 45 years.
      Radial and ulnar deviation were measured separately but were not significantly different. One study reported on the postoperative ROM which was not significantly different between PRC and FCA.
      • Aita M.A.
      • Nakano E.K.
      • Schaffhausser H.L.
      • Fukushima W.Y.
      • Fujiki E.N.
      Randomized clinical trial between proximal row carpectomy and the four-corner fusion for patients with stage II SNAC.

      Grip strength

      All studies but two reported on grip strength.
      • Brinkhorst M.E.
      • Singh H.P.
      • Dias J.J.
      • Feitz R.
      • Hovius S.E.R.
      Comparison of activities of daily living after proximal row carpectomy or wrist four-corner fusion.
      ,
      • Williams J.B.
      • Weiner H.
      • Tyser A.R.
      Long-term outcome and secondary operations after proximal row carpectomy or four-corner arthrodesis.
      Ten studies measured grip strength using a Jamar Dynamometer, three studies did not report on the SD and hence were excluded from the meta-analysis.
      • Krakauer J.D.
      • Bishop A.T.
      • Cooney W.P.
      Surgical treatment of scapholunate advanced collapse.
      ,
      • Bisneto E.N.
      • Freitas M.C.
      • Paula E.J.
      • Mattar R.
      • Zumiotti A.V.
      Comparison between proximal row carpectomy and four-corner fusion for treating osteoarthrosis following carpal trauma: a prospective randomized study.
      ,
      • Aita M.A.
      • Nakano E.K.
      • Schaffhausser H.L.
      • Fukushima W.Y.
      • Fujiki E.N.
      Randomized clinical trial between proximal row carpectomy and the four-corner fusion for patients with stage II SNAC.
      The three excluded studies did not report a significant difference in grip strength between the two groups. All remaining studies (N = 10) reported grip strength as a percentage compared to the contralateral non-operated hand.
      In the meta-analysis, no difference was observed in grip strength in FCA-treated patients compared to the PRC group: -0.02 (-0.13 – 0.10), P = 0.74 (Figure 6). High heterogeneity was noted among the studies (P < 0.01, I2 = 89%).
      Figure 6
      Figure 6Grip strength. This figure shows the mean difference between FCA and PRC in the percentage of grip strength compared to the non-operated hand in each study and the estimated 95% CI of this percentage using a Random Effects Model. The lowest diamond is the pooled mean difference of all studies. A negative value indicates that the FCA group had less strength than the PRC group.

      Complications and reoperations

      Complications resulting in a reoperation were reported in 12 studies and consisted of pin removal because of migration causing discomfort, carpal tunnel syndrome decompression, tenolysis, hematoma evacuation, Quervain's stenosing tenovaginitis, ulnar impaction, and scar revision. Three studies did not report on complications and reoperation.
      • Wolff A.L.
      • Garg R.
      • Kraszewski A.P.
      • et al.
      Surgical treatments for scapholunate advanced collapse wrist: kinematics and functional performance.
      ,
      • Brinkhorst M.E.
      • Singh H.P.
      • Dias J.J.
      • Feitz R.
      • Hovius S.E.R.
      Comparison of activities of daily living after proximal row carpectomy or wrist four-corner fusion.
      ,
      • De Smet L.
      • Degreef I.
      • Robijns F.
      • Truyen J.
      • Deprez P.
      Salvage procedures for degenerative osteoarthritis of the wrist due to advanced carpal collapse.
      The success of FCA partially relies on the successful union between the lunate, capitate, hamate, and triquetrum carpal bones. Adequate union facilitates the start of the rehabilitation process, therefore nonunion can delay this process, eventually affecting long-term outcomes. Nonunion rates were reported in ten studies, exclusively prevalent in FCA-treated patients due to the nature of the operative procedure. Seventeen (8.8%) cases of nonunion were reported among all studies. In some cases, non-union was an indicator for reoperation or conversion to TWA.
      In the meta-analysis, we found no significant difference in the number of complications resulting in reoperation between the two groups 0.03 (-0.03–0.10), P = 0.28 (Figure 7). Moderate heterogeneity was noted among the studies (P = 0.04, I2 = 45%).
      Figure 7
      Figure 7Complications & Reoperations. This figure shows the difference between FCA and PRC in the rate of reoperations because of complications in each study and the estimated 95% CI of this percentage using a Random Effects Model. The lowest diamond is the pooled percentage of all studies. A negative value indicates that the FCA group had a less ROM than the PRC group.

      Conversions to total wrist arthrodesis

      Since total wrist arthrodesis is a salvage procedure for failed FCA or PRC, conversion rates were reported in 12 studies, but not reported on in the three remaining studies.
      • Wolff A.L.
      • Garg R.
      • Kraszewski A.P.
      • et al.
      Surgical treatments for scapholunate advanced collapse wrist: kinematics and functional performance.
      ,
      • Brinkhorst M.E.
      • Singh H.P.
      • Dias J.J.
      • Feitz R.
      • Hovius S.E.R.
      Comparison of activities of daily living after proximal row carpectomy or wrist four-corner fusion.
      ,
      • De Smet L.
      • Degreef I.
      • Robijns F.
      • Truyen J.
      • Deprez P.
      Salvage procedures for degenerative osteoarthritis of the wrist due to advanced carpal collapse.
      In the meta-analysis, we found comparable conversion rates for both groups 0 (-0.03–0.04), P = 0.88 (Figure 8). There was no heterogeneity between the studies (P = 0.57, I2 = 0%).
      Figure 8
      Figure 8Conversion to Total Wrist Arthrodesis. This figure shows the difference between FCA and PRC in the rate of conversion to TWA in each study and the estimated 95% CI of this percentage using a Random Effects Model. The lowest diamond is the pooled percentage of all studies. A negative value indicates that the FCA group had a less ROM than the PRC group.
      The reason for conversion was persistent or severe pain after FCA or PRC in the majority of the studies.

      Pain

      Postoperative pain measurement was conducted in eight studies during follow-up visits. Two studies did not use the VAS pain score or perform statistical analysis.
      • Wyrick J.D.
      • Stern P.J.
      • Kiefhaber T.R.
      Motion-preserving procedures in the treatment of scapholunate advanced collapse wrist: proximal row carpectomy versus four-corner arthrodesis.
      ,
      • Krakauer J.D.
      • Bishop A.T.
      • Cooney W.P.
      Surgical treatment of scapholunate advanced collapse.
      The VAS pain score was used in six studies. However, we could pool only four of these studies, because of missing standard deviations in two articles which separately did not show a significant difference in postoperative pain score between the two groups.
      • Bisneto E.N.
      • Freitas M.C.
      • Paula E.J.
      • Mattar R.
      • Zumiotti A.V.
      Comparison between proximal row carpectomy and four-corner fusion for treating osteoarthrosis following carpal trauma: a prospective randomized study.
      ,
      • Dacho A.K.
      • Baumeister S.
      • Germann G.
      • Sauerbier M.
      Comparison of proximal row carpectomy and midcarpal arthrodesis for the treatment of scaphoid nonunion advanced collapse (SNAC-wrist) and scapholunate advanced collapse (SLAC-wrist) in stage II.
      In the meta-analysis, we found pooled postoperative pain scores to be comparable between the two groups -0.24 (-1.19–0.71), P = 0.47 (Figure 9). There was low heterogeneity among the studies (P = 0.27, I2 = 24%).
      Figure 9
      Figure 9VAS pain score. This figure shows the mean difference between FCA and PRC in VAS pain score in each study and the estimated 95% CI of this percentage using a Random-Effects Model. The lowest diamond is the pooled percentage of all studies. A negative value indicates that the FCA group had a less ROM than the PRC group.

      DASH scores

      DASH scores were reported in seven studies; of which three studies were excluded from the pooled analysis because of missing SD.
      • Bisneto E.N.
      • Freitas M.C.
      • Paula E.J.
      • Mattar R.
      • Zumiotti A.V.
      Comparison between proximal row carpectomy and four-corner fusion for treating osteoarthrosis following carpal trauma: a prospective randomized study.
      ,
      • Dacho A.K.
      • Baumeister S.
      • Germann G.
      • Sauerbier M.
      Comparison of proximal row carpectomy and midcarpal arthrodesis for the treatment of scaphoid nonunion advanced collapse (SNAC-wrist) and scapholunate advanced collapse (SLAC-wrist) in stage II.
      ,
      • Vanhove W.
      • De Vil J.
      • Van Seymortier P.
      • Boone B.
      • Verdonk R.
      Proximal row carpectomy versus four-corner arthrodesis as a treatment for SLAC (Scapholunate Advanced Collapse) wrist.
      In the meta-analysis, there was no difference in DASH scores between PRC and FCA treated patients 1.24 (-22.7–24.54), P = 0.88 (Figure 10). High heterogeneity was noted among the studies (P < 0.01, I2 = 92%).
      Figure 10
      Figure 10DASH Score. This figure shows the mean difference between FCA and PRC of the DASH score in each study and the estimated 95% CI of this percentage using a Random Effects Model. The lowest diamond is the pooled percentage of all studies. A negative value indicates that the FCA group had a less ROM than the PRC group.

      Discussion

      Clinical symptoms in SLAC and SNAC wrists can be variable. Patients can be asymptomatic or have significant wrist pain, reduced grip strength, or limited motion of the wrist joint. Conservative treatment strategies include the use of splints, anti-inflammatory medication, or corticosteroid injections. Surgical therapies are indicated in case conservative treatment fails. Preventive approaches to the underlying cause such as the scaphoid reconstruction of scapholunate interosseous ligament (SLIL) repair can be considered. The scapholunate ligament is important for maintaining carpal stability and a tear of this ligament disrupts the carpal kinematics and can lead to progression of disease.
      • Kitay A.
      • Wolfe S.W.
      Scapholunate instability: current concepts in diagnosis and management.
      There are different degrees of SLIL injury that may require a tailored approach.
      • Pappou I.P.
      • Basel J.
      • Deal D.N.
      Scapholunate ligament injuries: a review of current concepts.
      Scaphoid non-union happens when the scaphoid does not show signs of healing six months after the traumatic injury.
      • Borges C.S.
      • Ruschel P.H.
      • Pignataro M.B.
      Scaphoid reconstruction.
      Non-union of the scaphoid can result in deformities, incongruence, eventually leading to osteoarthritic changes. Scaphoid reconstruction can be considered if there are reliable cartilage surfaces in the radiocarpal joint, the scaphoid or both. SLAC and SNAC-induced degenerative osteoarthritis of the wrist, and the availability of several surgical therapies with different outcomes, can be dazzling for clinicians trying to select the best possible procedure. Options include a prosthetic scaphoid replacement, radial styloidectomy, wrist denervation, and total wrist arthrodesis. Nerve denervation is used to relieve patients of pain by severing the terminal branches of the anterior interosseous nerve or the posterior interosseous nerve and other fine articular branches from the other major nerves crossing the wrist joint. A recent study in 33 patients with a 41-month follow-up showed a 75% reduction in pain levels.
      • Delclaux S.
      • Elia F.
      • Bouvet C.
      • Apredoaei C.
      • Rongieres M.
      • Mansat P.
      Denervation of the wrist with two surgical incisions. Is it effective? A review of 33 patients with an average of 41months' follow-up.
      Whilst this method provides significant pain relief, it does not stop the ongoing osteoarthritis. Early-stage SLAC and SNAC affect the radial styloid and the scaphoid. Radial styloidectomy can be a suitable option for early-stage disease. In more advanced stages of the disease, PRC and FCA are the two most widely used surgical therapies.
      Over the last few decades, PRC and FCA have gained popularity and are among the most commonly used procedures to treat degenerative osteoarthritis. Both procedures provide pain relief and preserve ROM; however, because of the lack of RCTs, it remains unclear which procedure provides superior outcomes. We performed a meta-analysis and found no significant difference between ROM, grip strength, reoperation, conversion to TWA, pain, or DASH scores between the two groups. Although nonunion exclusively occurred in the FCA group, it did not affect the reoperation or conversion rate. Only two RCTs exist on this topic and our findings are comparable.
      • Bisneto E.N.
      • Freitas M.C.
      • Paula E.J.
      • Mattar R.
      • Zumiotti A.V.
      Comparison between proximal row carpectomy and four-corner fusion for treating osteoarthrosis following carpal trauma: a prospective randomized study.
      ,
      • Aita M.A.
      • Nakano E.K.
      • Schaffhausser H.L.
      • Fukushima W.Y.
      • Fujiki E.N.
      Randomized clinical trial between proximal row carpectomy and the four-corner fusion for patients with stage II SNAC.
      They did not show any significant difference in functional or clinical results between the two treatment methods.
      Watson and Ballet were the first to introduce FCA in 1984.
      • Watson H.K.
      • Ballet F.L.
      The SLAC wrist: scapholunate advanced collapse pattern of degenerative arthritis.
      According to Watson, FCA is the preferred treatment option for stage 3 collapse, mainly because the proximal pole of the capitate is involved in the degenerative process, thus excluding PRC as an option. Key question remains whether patients with stage 2 degeneration will have better outcomes with PRC or FCA. In the present study, we included all of the available literature comparing outcomes between PRC and FCA and pooled this data to derive a more robust conclusion. Including only comparative studies was important because of their relatively well-matched study populations and similarity in outcome measurements.
      Two systematic reviews are conducted on this topic. Mulford et al. conducted a systematic review comparing outcomes of 160 PRC and 185 FCA procedures.
      • Mulford J.S.
      • Ceulemans L.J.
      • Nam D.
      • Axelrod T.S.
      Proximal row carpectomy vs four-corner fusion for scapholunate (SLAC) or scaphoid nonunion advanced collapse (SNAC) wrists: a systematic review of outcomes.
      Their findings demonstrate that grip strength, pain relief, ROM, and subjective outcomes are comparable for both groups. They found PRC to have a higher range of osteoarthritic change after surgery, although in most cases asymptomatic, but the FCA group showed more complications (10% more) overall due to nonunion, dorsal impingement, and complications related to hardware. No differences in the rate of conversion to TWA were observed. This is in line with our findings. Importantly, the different surgical methods are used in performing FCA. This may, in part, explain the different complications rate reported in FCA-treated patients ranging from 2 to 11%.
      • Neubrech F.
      • Muhldorfer-Fodor M.
      • Pillukat T.
      • Schoonhoven J.
      • Prommersberger KJ.
      Long-term results after midcarpal arthrodesis.
      ,
      • Traverso P.
      • Wong A.
      • Wollstein R.
      • Carlson L.
      • Ashmead D.
      • Watson H.K.
      Ten-year minimum follow-up of 4-corner fusion for SLAC and SNAC wrist.
      Mulford et al. noticed more complications and found nonunion to be higher in patients receiving a plate as opposed to K-wires and screws. This topic has long been contested and no standard technique exists.
      Salzman et al. in a systematic review compared seven out of the 15 articles that were also included in our study.
      • Saltzman B.M.
      • Frank J.M.
      • Slikker W.
      • Fernandez J.J.
      • Cohen M.S.
      • Wysocki R.W.
      Clinical outcomes of proximal row carpectomy versus four-corner arthrodesis for post-traumatic wrist arthropathy: a systematic review.
      The overall complication rate in the FCA was significantly higher and double that in the PRC group. In the present study, we specifically studied complications requiring reoperation, as many of the complications reported by Salzman et al., such as nonunion in the included studies, remained asymptomatic and could be treated conservatively. The included studies remain unclear on the distribution of the number of patients with advanced SLAC/SNAC grade III receiving PRC of FCA. No statistically significant differences were observed compared to pain severity and satisfaction, DASH score, or conversion rates to TWA, which is in line with our findings.
      The outcomes of this study have to be interpreted keeping limitations in view. The majority of the included studies have a retrospective design with all of their inherent drawbacks, and are non-randomized, and include only a small number of patients. Statistical analysis is not performed in several instances, and SD or ranges are not mentioned precluding us from pooling the results. Only a minority of the studies measure the pre-operative status of the patients and compares that with the postoperative values. The lack of a baseline pre-operative value makes it particularly difficult to measure the degree of improvement postoperatively and compare it to other therapies. Several studies have shown the importance of preoperative clinical and functional measurements as a factor in estimating symptom relief after surgical treatment.
      • Zhou C.
      • Hovius S.E.
      • Slijper H.P.
      • et al.
      Predictors of patient satisfaction with hand function after fasciectomy for dupuytren's contracture.
      ,
      • Jansen M.C.
      • Evers S.
      • Slijper H.P.
      • et al.
      Predicting clinical outcome after surgical treatment in patients with carpal tunnel syndrome.
      In addition, the SLAC and SNAC grading distribution within treatment groups remains unclear in most studies, making it difficult to make recommendations based on SLAC/SNAC grading. A difference in failure or nonunion rates may be attributable to different SLAC/SNAC grading or related to the surgical experience of the operator. FCA is a much more challenging operation compared to PRC. As shown in Figure 3, many studies do not report the number of surgeons executing this operation. There are only a handful of studies where one or two surgeons performed both operations. We also evaluated the risk of bias with the NIH tool. All studies, except two, were observational and vulnerable to bias. The risk of bias was high in almost all studies because of a poorly defined patient population and the lack of specified inclusion and exclusion criteria. No study could blind the examiners during outcome measurements. These limitations and differences could be attributed to the high heterogeneity that was noted among the studies for ROM, grip strength, rate of reoperation, and DASH scores.
      Despite its limitations and the lack of multi-center randomized controlled trials, this study is the most up-to-date and comprehensive comparative systematic literature review and meta-analysis on comparing FCA and PRC in patients with degenerative SLAC and SNAC wrists. Compared to the most recent systematic review in 2015, this study contains eight more comparative studies and the largest number of patients treated with PRC or FCA. This study conducted a meta-analysis on the six most important postoperative outcome measures and is a significant update to the existing literature. Risk of bias assessment (lacking in previous studies) was also conducted to establish transparency and provide more insight into the included articles for comparison.
      Based on our findings, differences between average treatment effects could not be shown and may be relatively small when evidence accumulates. Since present studies all focus on comparing mean differences between treatments, for future studies, it may be more important to focus on patient-specific factors that determine treatment outcome, preferably, in the future, allowing clinicians to understand and predict which patients will benefit more or less from specific interventions. Based on this study, the authors suggest PRC as the preferred choice over the FCA, if there is no midcarpal osteoarthritis, because of the relative simplicity and the lack of need for a rather long learning curve compared to FCA. In addition, PRC lacks early postoperative hardware-related complications and provides comparable long-term outcomes.

      CRediT authorship contribution statement

      Ali R. Ahmadi: Writing – review & editing, Data curation, Writing – review & editing. Liron S. Duraku: Conceptualization, Writing – review & editing. Mark J.W. van der Oest: Formal analysis, Writing – review & editing. Caroline A. Hundepool: Writing – review & editing. Ruud W. Selles: Writing – review & editing. J. Michiel Zuidam: Conceptualization, Writing – review & editing.

      Declaration of Competing Interest

      None.

      Ethical approval

      Not required.

      Funding

      None.

      Acknowledgments

      The authors wish to thank Wichor M. Bramer, PhD and Maarten F.M. Engel from the Erasmus MC Medical Library for developing and updating the search strategies. We also wish to thank the medical illustrator Ella Nitters, MSc, MA for providing high-quality illustrations.

      Appendix. Supplementary materials

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