Does Distal Clavicle Resection Decrease Pain or Improve Shoulder Function in Patients With Acromioclavicular Joint Arthritis and Rotator Cuff Tears? A Meta-analysis : Clinical Orthopaedics and Related Research®

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CLINICAL RESEARCH

Does Distal Clavicle Resection Decrease Pain or Improve Shoulder Function in Patients With Acromioclavicular Joint Arthritis and Rotator Cuff Tears? A Meta-analysis

Wang, Jie MD; Ma, Jian-Xiong MD; Zhu, Shao-Wen MD; Jia, Hao-Bo MD; Ma, Xin-Long MD

Author Information

J. Wang, S.-W. Zhu, H.-B. Jia, X.-L. Ma, Department of Orthopaedics, Tianjin Hospital, Tianjin, China

J.-X. Ma, X.-L. Ma, Department of Orthopaedics Institute, Tianjin Hospital, Tianjin, China

J. Wang, Department of Orthopaedics, Tianjin Hospital, No. 406, Jiefang Nan Street, Hexi District, Tianjin, China, email: [email protected]

This work has received a specific grant (JW) from the National Natural Science Foundation of China (81601893).

All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research® editors and board members are on file with the publication and can be viewed on request.

Clinical Orthopaedics and Related Research® neither advocates nor endorses the use of any treatment, drug, or device. Readers are encouraged to always seek additional information, including FDA approval status, of any drug or device before clinical use.

Each author certifies that his or her institution waived approval for the human protocol for this investigation and that all investigations were conducted in conformity with ethical principles of research.

Clinical Orthopaedics and Related Research 476(12):p 2402-2414, December 2018. | DOI: 10.1097/CORR.0000000000000424

Abstract

Background 

Acromioclavicular joint arthritis is a common, painful, and often missed diagnosis, and it often accompanies other shoulder conditions such as rotator cuff disease. Whether distal clavicle resection is important to perform in patients undergoing surgery for rotator cuff tears and concomitant acromioclavicular joint arthritis is controversial.

Questions/purposes 

The purpose of this study was to perform a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the effect of distal clavicle resection on (1) outcome scores; (2) shoulder ROM, joint pain or tenderness, and joint instability; and (3) risk of reoperation among patients treated surgically for rotator cuff tears who had concomitant acromioclavicular joint arthritis.

Methods 

We systematically searched the PubMed, EMBASE, and Cochrane databases to find RCTs that met our eligibility criteria, which, in summary, (1) compared rotator cuff repair plus distal clavicle resection with isolated rotator cuff repair for patients who sustained a full- or partial-thickness rotator cuff tear and concomitant acromioclavicular joint arthritis; and (2) the followup period was at least 2 years. Two reviewers screened the studies, extracted the data and evaluated the methodological quality, and performed data analysis. Statistical heterogeneity among studies was quantitatively evaluated with the I2 index. No heterogeneity was detected (I2 = 0%; p = 0.75) in terms of acromioclavicular joint pain or tenderness, Constant score, forward flexion, external rotation, and risk of reoperation, so fixed-effect models were used in these endpoints. Heterogeneity was moderate for the American Shoulder and Elbow Surgeons (ASES) score (I2 = 53%; p = 0.12) and low for the visual analog scale (VAS) score (I2 = 35%; p = 0.22), so random-effect models were used in these endpoints. Subgroup analysis was stratified by the symptom of acromioclavicular joint arthritis. Three RCTs with 208 patients were included. We evaluated the risk of bias using the Cochrane risk-of-bias tool; in aggregate, the three RCTs included showed low to intermediate risk, although not all parameters of the Cochrane tool could be assessed for all studies.

Results 

There was no difference between the distal clavicle resection plus rotator cuff repair group and the isolated rotator cuff repair group in ASES score (mean difference =1.41; 95% confidence interval [CI], -3.37 to 6.18; p = 0.56) nor in terms of the VAS score and Constant score. Likewise, we found no difference in ROM of the shoulder (forward flexion, internal rotation, and external rotation) or acromioclavicular joint pain or tenderness between the groups (pooled results of acromioclavicular joint pain or tenderness: risk ratio [RR], 1.59; 95% CI, 0.67-3.78; p = 0.30). Acromioclavicular joint instability was only detected in the rotator cuff repair plus distal clavicle resection group. Finally, we found no difference in the proportion of patients undergoing repeat surgery between the study groups (pooled results of risk of reoperation for the rotator cuff repair plus distal clavicle resection and isolated rotator cuff repair: one of 52 versus two of 78; RR, 0.86; 95% CI, 0.11–6.48; p = 0.88).

Conclusions 

Distal clavicle resection in patients with rotator cuff tears did not result in better clinical outcome scores or shoulder ROM and was not associated with a lower risk of reoperation. Distal clavicle resection might cause acromioclavicular joint instability in patients with rotator cuff tears and concomitant asymptomatic acromioclavicular joint arthritis. Arthroscopic distal clavicle resection is not recommended in patients with rotator cuff tears and concomitant acromioclavicular joint arthritis. Additional well-designed RCTs with more participants, long-term followup, and data on patient-reported outcomes are needed.

Level of Evidence 

Level I, therapeutic study.

Introduction

Acromioclavicular joint arthritis is common [30], and it often accompanies other shoulder conditions such as rotator cuff disease [11] or glenohumeral arthritis [31]. Despite its frequency, this diagnosis often is missed [4]. Many studies have found a strong association between rotator cuff tears and acromioclavicular joint degenerative arthritis [16, 32, 43]. Furthermore, some studies have found that osteophytes located on the inferior aspect of the acromioclavicular joint can cause subacromial impingement and rotator cuff tears [10, 23, 32]. Hence, in patients with rotator cuff tears and concomitant acromioclavicular joint arthritis, the results of rotator cuff repair may be affected by not only patient age, tendon quality and the degree of retraction, and tendon suturing technique, but also by the performance (or nonperformance) of acromioplasty or acromioclavicular joint resection [5, 7, 18, 24].

Some surgeons believe that symptomatic acromioclavicular joint arthritis refractory to nonoperative treatment should be treated with distal clavicle resection. However, the pain level does not necessarily correlate well with the degree of age-related acromioclavicular joint arthritis changes such as joint space narrowing, medial acromial sclerosis, superior clavicular or marginal osteophytes, and capsular distention [12, 38]. Most patients with progressive, degenerative acromioclavicular joint disease remain asymptomatic [37]. Thus, it is difficult to make the decision to perform distal clavicle resection in patients with rotator cuff disease and concomitant symptomatic acromioclavicular joint degeneration.

For asymptomatic acromioclavicular joint arthritis, an accurate diagnosis and proper management are important, but the few studies that evaluated the efficacy of preventive arthroscopic distal clavicle resection in patients with rotator cuff tears and concomitant asymptomatic radiologic acromioclavicular joint arthritis reached opposite conclusions [17, 26]. Other studies have indicated that distal clavicle resection may lead to postoperative acromioclavicular joint pain and symptomatic instability and so did not recommend either open or arthroscopic distal clavicle resection [9, 13].

Whether distal clavicle resection decreases pain or improves shoulder function in patients with rotator cuff tears and concomitant acromioclavicular joint arthritis is controversial. We therefore performed a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the effect of distal clavicle resection on (1) outcome scores; (2) shoulder ROM, acromioclavicular joint pain or tenderness, and joint instability; and (3) risk of reoperation among patients treated surgically for rotator cuff tears who had concomitant acromioclavicular joint arthritis.

Patients and Methods

Inclusion and Exclusion Criteria

This systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines [22]. Inclusion criteria for our systematic review and meta-analysis were studies that evaluated patients with (1) a full- or partial-thickness rotator cuff tear shown on preoperative MRI who underwent arthroscopic rotator cuff repair; (2) ipsilateral acromioclavicular joint arthritis confirmed by plain radiographs or shoulder MRI, whether symptomatic or not; (3) no previous shoulder surgery; (4) in the setting of a RCT; (5) with at least 2 years’ followup. We excluded retrospective studies, laboratory studies (including those using cadaver material), trials with incomplete or unavailable data; reviews, letters, or comments; and duplicated publications (in those cases, keeping the paper with the most complete data).

Search Strategy

We searched PubMed (MEDLINE), EMBASE, and the Cochrane Central Register of Controlled trials databases from their inception to December 31, 2017. There was no language restriction. The search terms “rotator cuff tear”, “rotator cuff injury”, “rotator cuff tendon repair”, “acromioclavicular joint”, and “distal clavicle resection” were used in the search strategy (see Table, Supplemental Digital Content). We also searched conference proceedings and the bibliographies of reviews and included articles manually to ensure that all relevant studies were checked for our systematic review and meta-analysis.

Study Selection

Two independent authors (JW, J-XM) performed the study selection. Any disagreements during full-text inclusion were resolved by discussion, and if necessary, the third author (X-LM) would adjudicate. This strategy retrieved 69 potential eligible citations. After removing 12 duplicates, the titles and abstracts of 57 publications were scanned. At this stage, we excluded studies that did not fulfill the eligibility criteria. After excluding 48 publications, we assessed the full text of the remaining five studies for eligibility criteria. We excluded two studies because they were not randomized [2, 34], leaving three studies to be included in our systematic review and meta-analysis [17, 26, 28] (Fig. 1).

F1
Fig. 1:
Study selection flow diagram shows the process of publication selection.

Data Extraction

Using a standardized data extraction approach, two independent reviewers (JW, S-WZ) extracted the following data from the included studies: title, published year, authors, country, study design, study period, number of study centers, sample size, patient age, sex distribution, the characteristic of patients, intervention types, followup duration, and outcomes. Discrepancies were arbitrated by consensus with a third reviewer (X-LM). The authors each verified data accuracy. The evaluated outcomes included the American Shoulder and Elbow Surgeons (ASES) score [35] and the Constant score [8] for the assessment of function of the shoulder, the visual analog scale (VAS) for pain severity, ROM (forward flexion, internal rotation, external rotation, and abduction), acromioclavicular joint pain or tenderness, acromioclavicular joint instability, and the reoperation rate. In Park et al.’s study [28], a lidocaine injection test was performed to confirm localized acromioclavicular joint tenderness, and a focused physical examination was performed to assess acromioclavicular joint tenderness provoked by direct joint palpation. The acromioclavicular joint pain was assessed by the Paxinos test and tenderness in Oh et al.’s study [26], and the cross-body adduction test and tenderness were used in Kim et al.’s study [17]. The dedicated acromioclavicular joint views of both shoulders with and without stress loading of 10 pounds evaluated acromioclavicular joint stability in Oh et al.’s study [26]. Kim et al.’s study [17] did not report the method used to assess the stability of the acromioclavicular joint. If relevant data were not reported, the authors were contacted by email. Means and SDs were extracted for all continuous outcomes. If these values were not reported, they were derived indirectly from p values or confidence intervals when possible.

The ASES score is scored on a 100-point scale with higher numbers representing better function and pain [35]; the minimum clinically important difference (MCID) of the ASES score is 6.4 points [21]. The Constant score also is scored on a 100-point scale with higher numbers representing better function [8]; the MCID of this score is unknown. The VAS is scored on a 10-point scale [20] with higher numbers representing more pain; the MCID is believed to be approximately 1.4 points [40].

The primary outcome was the ASES score. The Constant score, VAS score, ROM, acromioclavicular joint pain or tenderness, acromioclavicular joint instability, and the risk of reoperation were secondary outcomes.

Three RCTs [17, 26, 28] reported the ASES score, VAS score, and acromioclavicular joint pain or tenderness. There was moderate heterogeneity across studies in terms of the ASES score (p = 0.12; I2 = 53%), and a random-effects model was used for this endpoint. There was low heterogeneity across studies in terms of the VAS score (p = 0.22; I2 = 35%), and a random-effects model was used for this endpoint. The fixed-effect model was applied for the endpoint of acromioclavicular joint pain or tenderness, because no heterogeneity was found in terms of this endpoint (p = 0.44; I2 = 0%). Two RCTs [26, 28] reported the Constant score and shoulder ROM. One study [26] included patients with asymptomatic acromioclavicular joint arthritis, and the other [28] included patients with symptomatic acromioclavicular joint arthritis. No heterogeneity was detected for the Constant score (p = 0.75; I2 = 0%), and so the fixed-effect model was used for it. No heterogeneity was detected for forward flexion (p = 0.78; I2 = 0%) and external rotation (p = 0.93; I2 = 0%), and fixed-effects models were used for these endpoints. Two RCTs [17, 26] that included patients with asymptomatic acromioclavicular joint arthritis reported acromioclavicular joint instability. Two RCTs [17, 28] reported risk of reoperation. Kim et al.’s study [17] included patients with asymptomatic acromioclavicular joint arthritis, whereas Park et al.’s study [28] included symptomatic patients. No heterogeneity was detected for this outcome (p = 0.70; I2 = 0%), so the fixed-effects model was used here.

Study Characteristics

Three RCTs satisfied the inclusion criteria [17, 26, 28]. A total of 208 patients were reported, including 91 patients with rotator cuff repair plus distal clavicle resection and 117 patients with an isolated rotator cuff repair. The studies by Kim et al. [17] and Oh et al. [26] included patients who sustained rotator cuff tears and concomitant asymptomatic acromioclavicular joint arthritis, whereas the study by Park et al. [28] included patients who sustained rotator cuff tears and concomitant symptomatic acromioclavicular joint arthritis. All the patients in the studies by Oh et al. [26] and Park et al. [28] underwent acromioplasty. However, in the study by Kim et al. [17], 16.1% patients in the rotator cuff repair plus distal clavicle resection group and 15.4% patients in the isolated rotator cuff repair group underwent acromioplasty. The followup of the rotator cuff repair plus distal clavicle resection group and isolated rotator cuff repair group in Kim et al.’s study [17] was 32.8 ± 4.1 months and 31.9 ± 4.9 months, respectively; no patients were lost to followup in this study. In Oh et al.’s study [26], the followup was 27.6 ± 6.7 months in the rotator cuff repair plus distal clavicle resection group and 30.7 ± 7.2 months in the isolated rotator cuff repair group; 11 patients in each group were lost to followup. In Park et al.’s study [28], the followup was 44.19 ± 9.84 months in the rotator cuff repair plus distal clavicle resection group and 44.03 ± 9.47 months in the isolated rotator cuff repair group; two patients in the rotator cuff repair plus distal clavicle resection group and three patients in the isolated rotator cuff repair group were lost to followup (Table 1). Two RCTs [26, 28] reported that there were no differences between the two study groups in ASES score, VAS score, Constant score, forward flexion, internal rotation, or external rotation. One RCT [17] detected a difference between the two study groups in ASES score and VAS score (Table 2).

T1
Table 1.:
Characteristics of the included studies
T2
Table 2.:
Main findings of the included studies

Risk of Bias Assessment

Two reviewers (JW, H-BJ) independently evaluated the methodological quality and the risk of bias of the included RCTs using the Cochrane risk-of-bias tool [15]. Disagreements were resolved by consulting a third reviewer (X-LM). Included trials were carefully reviewed and scored as high, low, or unclear risk of bias according to the following criteria: random sequence generation, allocation concealment, blinding of participants and personnel, blinding of outcome assessment, incomplete outcome data, selective reporting, and other bias. Of the included trials, random sequence generation was appropriate in all RCTs [17, 26, 28]. Allocation concealment was unclear in all RCTs. Only one study [28] scored as low risk of bias with respect to blinding of participants and personnel. Another two RCTs [17, 26] presented as unclear in this domain. As to blinding of outcome assessment, two RCTs [26, 28] showed low risk of bias and one RCT [17] was unclear in this domain. In terms of incomplete outcome data, all the RCTs [17, 26, 28] suggested low risk of bias. All RCTs [17, 26, 28] showed low risk of selective reporting. Other elements on the risk-of-bias tool for these RCTs [17, 26, 28] were unclear (Fig. 2).

F2
Fig. 2:
Assessment of risk of bias for the included studies is shown. + = low risk of bias; – = high risk of bias; ? = unclear or unknown risk of bias.

Publication Bias

To evaluate for the potential of publication bias, we performed a funnel plot from one of the primary outcomes–ASES score–which was available in all three studies (Fig. 3). The shape of the funnel plot was asymmetric, suggesting possible publication bias. However, the assessment should not be considered robust because of the small number of eligible studies.

F3
Fig. 3:
The funnel plot of the included studies is asymmetric, indicating the presence of publication bias. SE = standard error.

Data Synthesis and Analysis

For statistical analysis, two reviewers (JW, S-WZ) used the software program RevMan 5.1 (The Nordic Cochrane Center, The Cochrane Collaboration, Copenhagen, Denmark). Mean difference (MD) with a 95% confidence interval (CI) was calculated to assess the effect size for continuous outcome data. Risk ratio (RR) with a 95% CI was used as the effect size for dichotomous data. We used the inverse variance method for continuous variables and the Mantel-Haenszel analysis method for dichotomous variables [19]. The heterogeneity among the trials was assessed for significance with Q and quantified with I2. An I2 < 25% was considered homogeneous, an I2 between 25% and 50% as low heterogeneity, an I2 between 50% and 75% as moderate heterogeneity, and an I2 > 75% as high heterogeneity [41]. We used a fixed-effect model when the studies were homogeneous and a random-effect model when the statistical heterogeneity was low to high. The subgroup analysis was stratified by the existence or nonexistence of acromioclavicular joint symptoms. When three studies were included in the comparisons, sensitivity analysis was done by omitting one or more studies that might increase the heterogeneity of each outcome to see whether specified factors could influence the overall effects of each outcome [42]. When only one study was included, or the data could not be synthetized, we conducted a systematic review according to the reported outcomes.

With the numbers available, at an alpha level of < 0.05, we had 61% power to detect a difference of 6.4 points on the ASES score, which is the MCID for that score [21].

Results

ASES Score, VAS Score, and Constant Score

The overall pooled result of the three included studies showed no difference between the rotator cuff repair plus distal clavicle resection group and the isolated rotator cuff repair group in terms of the ASES score (MD, 1.41; 95% CI, -3.37 to 6.18; p = 0.56; Fig. 4). Sensitivity analysis for this overall pooled result showed that concomitant distal clavicle resection was related to a greater increase in ASES score compared with isolated rotator cuff repair among patients with rotator cuff tears and concomitant acromioclavicular joint arthritis undergoing arthroscopy rotator cuff repair (MD, 3.72; 95% CI, 1.58–5.86; p < 0.001; I2 = 0%, fixed-effect model), when omitting the study by Oh et al. [26]. Subgroup analysis showed no difference in the asymptomatic acromioclavicular joint arthritis subgroup between the two study groups (Table 3).

F4
Fig. 4 A-C:
The forest plot shows the overall results of ASES score (A), VAS (B) and Constant score (C) between the DCR + RCR group and the isolated RCR group. df = degrees of freedom; IV = inverse variance.
T3
Table 3.:
Subgroup analysis of the outcomes

The overall pooled result of the three included studies also showed no difference between the rotator cuff repair plus distal clavicle resection group and the isolated rotator cuff repair group in terms of the VAS (MD, -0.38; 95% CI, -0.79 to 0.03; p = 0.07; Fig. 4). Sensitivity analysis showed that concomitant distal clavicle resection was related to a lower VAS score compared with isolated rotator cuff repair among patients with rotator cuff tears and concomitant acromioclavicular joint arthritis undergoing arthroscopy rotator cuff repair (MD, -0.57; 95% CI, -0.86 to -0.28; p < 0.001; I2 = 0%, fixed-effect model) when omitting the study by Oh et al. [26]. Subgroup analysis showed no difference in the asymptomatic acromioclavicular joint arthritis subgroup between the two study groups (Table 3).

Both studies that evaluated Constant scores [26, 28] found no differences between the two groups in terms of that endpoint. The overall pooled result of the two included studies also showed no difference between the two groups (MD, 0.69; 95% CI, -1.54 to 2.92; p = 0.55; Fig. 4).

Shoulder ROM, Acromioclavicular Joint Tenderness, and Instability

No differences were detected in forward flexion and external rotation (forward flexion: MD, -1.96; 95% CI, -6.17 to 2.25; p = 0.36; external rotation: MD, 2.43; 95% CI, -3.13 to 7.99; p = 0.39; Fig. 5). One study [26] included patients with asymptomatic acromioclavicular joint arthritis and detected no differences between the study groups in forward flexion, abduction, external rotation, or internal rotation. The other study [28], which included patients with symptomatic acromioclavicular joint, detected no differences between the groups in forward flexion, external rotation, or internal rotation. Because Park et al. [28] did not report the abduction data and the SD of the internal rotation, the effective overall pooled analysis could only be performed for forward flexion and external rotation.

F5
Fig. 5:
The forest plot shows the overall results of ROM of the injured shoulder between the DCR + RCR group and the isolated RCR group. df = degrees of freedom; IV = inverse variance.

We also found no difference in terms of acromioclavicular joint pain or tenderness (RR, 1.59; 95% CI, 0.67-3.78; p = 0.30; Fig. 6). The sensitivity analysis showed that the overall effect could not be influenced by omitting any single study for this comparison. Subgroup analysis showed no difference in the asymptomatic acromioclavicular joint arthritis subgroup between the two study groups (Table 3).

F6
Fig. 6:
The forest plot shows the overall results of acromioclavicular joint pain or tenderness between the DCR + RCR group and the isolated RCR group. df = degrees of freedom; M-H = Mantel-Haenszel.

In Kim et al. [17], no patients developed acromioclavicular joint instability after operation in the two groups. Oh et al. [26] reported that two patients developed acromioclavicular joint instability in the rotator cuff repair plus distal clavicle resection group, whereas no patients developed it in the isolated rotator cuff repair group. Hence, we could not perform an effective pooled analysis.

Risk of Reoperation

We found no differences between the two study groups (RR, 0.86; 95% CI, 0.11–6.48; p = 0.88; Fig. 7). However, both studies reported no differences in risk of reoperation between the two groups.

F7
Fig. 7:
The forest plot shows the overall results of the risk of reoperation between the DCR + RCR group and the isolated RCR group. df = degrees of freedom; M-H = Mantel-Haenszel.

Discussion

The coexistence of rotator cuff tears and acromioclavicular joint arthritis is common. In these patients, the frequency and severity of acromioclavicular joint symptoms do not seem to be correlated with the severity of the radiographic signs of arthritis [14]. On the other hand, asymptomatic acromioclavicular joint arthrosis may progress to symptomatic acromioclavicular joint arthritis and affect rotator cuff healing after rotator cuff repair [33]. In addition, some studies have reported a correlation between the presence of osteophytes in the inferior aspect of the joint and symptoms of subacromial impingement or rotator cuff tears [10, 23, 32], and some authors believe that subclinical osteophytes at the inferior surface of the shoulder can irritate or tear rotator cuff tendons [10, 16]. These reasons support the concept of distal clavicle resection. However, some studies indicated that any procedure involving the acromioclavicular joint is a risk factor for late-onset acromioclavicular joint pain and instability [9, 13]. For these reasons, surgeons must carefully consider whether to perform distal clavicle resection in patients with rotator cuff tears and concomitant symptomatic acromioclavicular degeneration, but to date, few high-quality studies speak to the topic, and some of these studies disagree with one another [17, 26]. Therefore, data pooling in meta-analysis can help guide us. After pooling the best available evidence, we found no apparent benefit of distal clavicle resection in the setting of treatment of patients with rotator cuff tears and acromioclavicular joint arthritis.

Limitations

The results of this study should be interpreted with caution because of the following limitations. First, only three studies [17, 26, 28] met our inclusion criteria, and this left only 208 patients for analysis. However, this still gave us adequate power to detect clinically important differences on the ASES score [21] had they been present. Only one study [28] included a symptomatic acromioclavicular joint arthritis subgroup, so we could not conduct a meta-analysis on this endpoint, forcing us to draw a conclusion based on this one study. As more studies get published, it is conceivable the findings could change, but our findings here are drawn from the best available evidence on the topic today. Second, there was low-to-moderate heterogeneity among the studies in ASES and VAS scores. Because we were limited by the number of included studies in each outcome, we could not perform metaregression to explore the source of this heterogeneity. However, after analyzing the characteristics of the included studies, we believe the cause of this heterogeneity might be derived from the study by Kim et al. [17]. In that study, inferiorly directed osteophytes of the acromioclavicular joint existed in all patients, but acromioplasty was performed on only 13 of 83 patients. Some studies have indicated that acromioclavicular joint arthritis was attributed to rotator cuff impingement in a combination of mechanical abrasion from inferiorly directed osteophytes [10, 30, 32] and incomplete healing from hypovascularity [33]. These may provide evidence that inferiorly directed osteophytes are mechanically and biologically related to a rotator cuff tear and its healing environment. Third, one study [28] did not provide acromioclavicular joint instability data, and one study [17] did not detect this complication. Because of this, we could not perform a meta-analysis on that endpoint. Instead, we performed a systematic review and drew a descriptive conclusion.

We also note that all the included studies [17, 26, 28] were from South Korea, and so the conclusions of this systematic review and meta-analysis might not generalize to other patient populations. Finally, only Oh et al.’s study [26] reported biceps pathology and tenotomy or tenodesis, and in Kim et al.’s study [17], acromioplasty was not performed in all patients. These might be the sources of some of the heterogeneity among the studies in terms of ASES and VAS scores. However, it was difficult to quantify the effects of these variabilities on the treatments, because metaregression could not be performed. Finally, publication bias was detected because the funnel plot was asymmetric. However, because of the limited number of included studies, it is impossible to know with certainty the degree to which this may have influenced our findings. Therefore, additional well-designed RCTs with more participants, long-term followup, and data on patient-reported outcomes are needed to confirm whether arthroscopic distal clavicle resection is important for the treatment of patients with rotator cuff tears and concomitant asymptomatic or symptomatic acromioclavicular joint arthritis.

Outcome Scores

Some studies have found that distal clavicle resection can help manage refractory symptomatic acromioclavicular joint arthritis in patients without rotator cuff tears [25, 27] and that it can be performed arthroscopically [6, 29]. However, we found no apparent benefit to adding a distal clavicle resection to a rotator cuff repair procedure in patients with concomitant acromioclavicular joint arthritis in terms of ASES, Constant, or VAS scores when compared with isolated rotator cuff repair. We cannot draw inferences from the available data about the cause of this finding, although we note that Ryu et al. [36] showed that in the absence of obvious symptoms of acromioclavicular joint pathology, the joint should be left intact during the surgical procedure. In addition, the sensitivity analysis by omitting Oh et al.’s study [26] in our meta-analysis showed that concomitant distal clavicle resection was associated with a higher ASES score and a lower VAS score compared with isolated rotator cuff repair among patients with rotator cuff tears and concomitant acromioclavicular joint arthritis undergoing arthroscopic rotator cuff repair, suggesting some uncertainty in this finding; additional studies might change the results.

Shoulder ROM, Joint Pain or Tenderness, and Instability

Our study showed that there were no differences between the two groups in terms of shoulder ROM. However, we believe that because acromioclavicular joint arthritis is a kind of amphiarthrosis, it probably has little effect on shoulder ROM, and when the acromioclavicular joint causes more severe pain or instability, the shoulder itself may be affected. Because so few randomized studies have looked at shoulder ROM after these procedures [26, 28], we encourage others to evaluate ROM to improve our evidence base in this regard; however, based on what we found in the current meta-analysis, there does not appear to be a difference between the rotator cuff repair plus distal clavicle resection group and the isolated rotator cuff repair group.

One study indicated that any procedure involving the acromioclavicular joint is a risk factor for late-onset acromioclavicular joint pain [13]. Another study showed that insufficient resection of the distal clavicle during an arthroscopic approach could lead to persistent acromioclavicular joint pain postoperatively [39]. However, our study showed that there were no statistical differences between the two groups in acromioclavicular joint pain or tenderness for the treatment of patients with rotator cuff tears and concomitant asymptomatic or symptomatic acromioclavicular joint arthritis. Therefore, persistent pain in symptomatic acromioclavicular joint arthritis and newly developed pain in asymptomatic acromioclavicular joint arthritis might be caused by an insufficient distal clavicle resection. Incomplete resection of the superior or posterior cortex of the distal clavicle is a potential cause of persistent pain that has been more commonly reported after arthroscopic techniques [39]. The biomechanical study performed by Branch et al. [3] showed that a minimum of 5 mm of the distal clavicle must be removed to prevent postoperative bone-on-bone contact [3]. Furthermore, it is critical to view the resection in two planes during the procedure to confirm adequate bone resection [39]. Park et al. [28] and Oh et al. [26] resected 5 to 8 mm of bone, but they confirmed it in one plane by viewing it either from the anterior portal or lateral portal.

A distal clavicle resection has a potentially negative effect on acromioclavicular joint stability because of capsular violation and bony resection. Subsequent acromioclavicular joint instability could lead to symptomatic acromioclavicular joints, especially in patients with acromioclavicular joint arthritis. The main component of joint stability is the capsular and ligamentous structures of the acromioclavicular joint [9]. However, there is little margin for error to excise the distal clavicle completely without sacrificing some of those structures. The superior acromioclavicular ligament is generally severed during resection. One study reported that only 37% of patients treated with arthroscopic distal clavicle resection for posttraumatic arthritis obtained satisfactory results because of persistent instability [1].

Risk of Reoperation

We detected no differences in the risk of reoperation between the rotator cuff repair plus distal clavicle resection group and the isolated rotator cuff repair group. In patients with rotator cuff tears and concomitant acromioclavicular joint arthritis, the reasons for reoperation were retears of the rotator cuff or persistent or newly developed acromioclavicular joint pain. Kim et al. [17] reported that the reason for reoperation was newly developed acromioclavicular joint pain, and Park et al. [28] did not report the reason. More studies are needed.

Conclusions

Pooled results from this systematic review and meta-analysis found that distal clavicle resection in patients with rotator cuff tears did not result in improved ASES scores, VAS scores, Constant scores, or shoulder ROM nor did it decrease acromioclavicular joint pain or tenderness or lower the risk of reoperation. Shoulder abduction was not different between the two groups in patients with rotator cuff and concomitant asymptomatic acromioclavicular joint arthritis. Distal clavicle resection might cause acromioclavicular joint instability in patients with rotator cuff tears and concomitant asymptomatic acromioclavicular joint arthritis. Arthroscopic distal clavicle resection therefore is not recommended in patients with rotator cuff tears and concomitant acromioclavicular joint arthritis. Additional well-designed RCTs with adequate numbers of participants, long-term followup, and full data on patient-reported outcomes are needed.

References

1. Bigliani LU, Nicholson GP, Flatow EL. Arthroscopic resection of the distal clavicle. Orthop Clin North Am. 1993;24:133–141.
2. Blasiak A, Mojzesz M, Brzoska R, Solecki W, Binkowska A. Results of arthroscopic treatment of rotator cuff tear with the resection of symptomatic acromioclavicular joint with degenerative changes. Pol Orthop Traumatol. 2013;78:229–234.
3. Branch TP, Burdette HL, Shahriari AS, Carter FN, Hutton WC. The role of the acromioclavicular ligaments and the effect of distal clavicle resection. Am J Sports Med. 1996;24:293–297.
4. Buttaci CJ, Stitik TP, Yonclas PP, Foye PM. Osteoarthritis of the acromioclavicular joint: a review of anatomy, biomechanics, diagnosis, and treatment. Am J Phys Med Rehabil. 2004;83:791–797.
5. Chahal J, Mall N, MacDonald PB, Van Thiel G, Cole BJ, Romeo AA, Verma NN. The role of subacromial decompression in patients undergoing arthroscopic repair of full-thickness tears of the rotator cuff: a systematic review and meta-analysis. Arthroscopy. 2012;28:720–727.
6. Charron KM, Schepsis AA, Voloshin I. Arthroscopic distal clavicle resection in athletes: a prospective comparison of the direct and indirect approach. Am J Sports Med. 2007;35:53–58.
7. Chen M, Xu W, Dong Q, Huang Q, Xie Z, Mao Y. Outcomes of single-row versus double-row arthroscopic rotator cuff repair: a systematic review and meta-analysis of current evidence. Arthroscopy. 2013;29:1437–1449.
8. Constant CR, Murley AH. A clinical method of functional assessment of the shoulder. Clin Orthop Relat Res. 1987;214:160–164.
9. Corteen DP, Teitge RA. Stabilization of the clavicle after distal resection: a biomechanical study. Am J Sports Med. 2005;33:61–67.
10. Cuomo F, Kummer FJ, Zuckerman JD, Lyon T, Blair B, Olsen T. The influence of acromioclavicular joint morphology on rotator cuff tears. J Shoulder Elbow Surg. 1998;7:555–559.
11. Daluga DJ, Dobozi W. The influence of distal clavicle resection and rotator cuff repair on the effectiveness of anterior acromioplasty. Clin Orthop Relat Res. 1989;247:117–123.
12. DePalma AF. The classic. Surgical anatomy of the rotator cuff and the natural history of degenerative periarthritis. Clin Orthop Relat Res. 2008;466:543–551.
13. Fischer BW, Gross RM, McCarthy JA, Arroyo JS. Incidence of acromioclavicular joint complications after arthroscopic subacromial decompression. Arthroscopy. 1999;15:241–248.
14. Gartsman GM, Combs AH, Davis PF, Tullos HS. Arthroscopic acromioclavicular joint resection. An anatomical study. Am J Sports Med. 1991;19:2–5.
15. Higgins JP, Altman DG, Gotzsche PC, Juni P, Moher D, Oxman AD, Savovic J, Schulz KF, Weeks L, Sterne JA. The Cochrane Collaboration's tool for assessing risk of bias in randomised trials. BMJ. 2011;343:d5928.
16. Kessel L, Watson M. The painful arc syndrome. Clinical classification as a guide to management. J Bone Joint Surg Br. 1977;59:166–172.
17. Kim J, Chung J, Ok H. Asymptomatic acromioclavicular joint arthritis in arthroscopic rotator cuff tendon repair: a prospective randomized comparison study. Arch Orthop Traum Surg. 2011;3:363–369.
18. MacDonald P, McRae S, Leiter J, Mascarenhas R, Lapner P. Arthroscopic rotator cuff repair with and without acromioplasty in the treatment of full-thickness rotator cuff tears: a multicenter, randomized controlled trial. J Bone Joint Surg Am. 2011;93:1953–1960.
19. Mantel N, Haenszel W. Statistical aspects of the analysis of data from retrospective studies of disease. J Natl Cancer Inst. 1959;22:719–748.
20. McCormack HM, Horne DJ, Sheather S. Clinical applications of visual analogue scales: a critical review. Psychol Med. 1988;18:1007–1019.
21. Michener LA, McClure PW, Sennett BJ. American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form, patient self-report section: reliability, validity, and responsiveness. J Shoulder Elbow Surg. 2002;11:587–594.
22. Moher D, Shamseer L, Clarke M, Ghersi D, Liberati A, Petticrew M, Shekelle P, Stewart LA. Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015 statement. Syst Rev. 2015;4:1.
23. Neer CN. Impingement lesions. Clin Orthop Relat Res. 1983;173:70–77.
24. Nho SJ, Brown BS, Lyman S, Adler RS, Altchek DW, MacGillivray JD. Prospective analysis of arthroscopic rotator cuff repair: prognostic factors affecting clinical and ultrasound outcome. J Shoulder Elbow Surg. 2009;18:13–20.
25. Nuber GW, Bowen MK. Arthroscopic treatment of acromioclavicular joint injuries and results. Clin Sports Med. 2003;22:301–317.
26. Oh JH, Kim JY, Choi JH, Park SM. Is arthroscopic distal clavicle resection necessary for patients with radiological acromioclavicular joint arthritis and rotator cuff tears? A prospective randomized comparative study. Am J Sports Med. 2014;42:2567–2573.
27. Park TS, Lee KW. Arthroscopic resection of the distal clavicle in osteoarthritis of the acromioclavicular joint. Indian J Orthop. 2016;50:379–383.
28. Park YB, Koh KH, Shon MS, Park YE, Yoo JC. Arthroscopic distal clavicle resection in symptomatic acromioclavicular joint arthritis combined with rotator cuff tear: a prospective randomized trial. Am J Sports Med. 2015;43:985–990.
29. Pensak M, Grumet RC, Slabaugh MA, Bach BJ. Open versus arthroscopic distal clavicle resection. Arthroscopy. 2010;26:697–704.
30. Petersson CJ. Degeneration of the acromioclavicular joint. A morphological study. Acta Orthop Scand. 1983;54:434–438.
31. Petersson CJ. The acromioclavicular joint in rheumatoid arthritis. Clin Orthop Relat Res. 1987;223:86–93.
32. Petersson CJ, Gentz CF. Ruptures of the supraspinatus tendon. The significance of distally pointing acromioclavicular osteophytes. Clin Orthop Relat Res. 1983;174:143–148.
33. Rathbun JB, Macnab I. The microvascular pattern of the rotator cuff. J Bone Joint Surg Br. 1970;52:540–553.
34. Razmjou H, ElMaraghy A, Dwyer T, Fournier-Gosselin S, Devereaux M, Holtby R. Outcome of distal clavicle resection in patients with acromioclavicular joint osteoarthritis and full-thickness rotator cuff tear. Knee Surg Sports Traumatol Arthrosc. 2015;23:585–590.
35. Richards RR, An KN, Bigliani LU, Friedman RJ, Gartsman GM, Gristina AG, Iannotti JP, Mow VC, Sidles JA, Zuckerman JD. A standardized method for the assessment of shoulder function. J Shoulder Elbow Surg. 1994;3:347–352.
36. Ryu RK, Burkhart SS, Parten PM, Gross RM. Complex topics in arthroscopic subacromial space and rotator cuff surgery. Arthroscopy. 2002;18:51–64.
37. Shaffer BS. Painful conditions of the acromioclavicular joint. J Am Acad Orthop Surg. 1999;7:176–188.
38. Stein BE, Wiater JM, Pfaff HC, Bigliani LU, Levine WN. Detection of acromioclavicular joint pathology in asymptomatic shoulders with magnetic resonance imaging. J Shoulder Elbow Surg. 2001;10:204–208.
39. Strauss EJ, Barker JU, McGill K, Verma NN. The evaluation and management of failed distal clavicle excision. Sports Med Arthrosc Rev. 2010;18:213–219.
40. Tashjian RZ, Hung M, Keener JD, Bowen RC, McAllister J, Chen W, Ebersole G, Granger EK, Chamberlain AM. Determining the minimal clinically important difference for the American Shoulder and Elbow Surgeons score, Simple Shoulder Test, and visual analog scale (VAS) measuring pain after shoulder arthroplasty. J Shoulder Elbow Surg. 2017;26:144–148.
41. Wang J, Yang Y, Ma J, Xing D, Zhu S, Ma B, Chen Y, Ma X. Open reduction and internal fixation versus external fixation for unstable distal radial fractures: a meta-analysis. Orthop Traumatol Surg Res. 2013;99:321–331.
42. Wang J, Zhang L, Ma J, Yang Y, Jia H, Ma X. Is intramedullary nailing better than the use of volar locking plates for fractures of the distal radius? A meta-analysis of randomized controlled trials. J Hand Surg Eur Vol. 2016;41:543–552.
43. Watson M. The refractory painful arc syndrome. J Bone Joint Surg Br. 1978;60:544–546.

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