The purpose of the present study was to investigate whether glenohumeral arthroscopic exploration is justified in patients with CTS based on the prevalence of intraarticular pathologies that require surgical treatment. This study adds evidence that glenohumeral pathologies have a low prevalence in patients undergoing arthroscopic removal of rotator cuff calcifications. Outcome of this study suggests that a standardized diagnostic glenohumeral exploration may not be mandatory as a routine procedure during arthroscopic treatment of CTS. As far as we are aware, there is no previous investigation specifically analyzing the prevalence of intraarticular glenohumeral pathologies during arthroscopic removal of rotator cuff calcifications.
Minimally invasive removal of rotator cuff calcifications
Most commonly, treatment of symptomatic CTS can be managed non-operatively (90% of patients) by physiotherapy, analgesics, and injections [
27]. Surgical treatment is reserved for patients in which conservative therapy has failed, such as prolonged periods of functional disability, severe pain, and when calcific deposits do not resolve spontaneously. To date, most surgeons perform an arthroscopic removal of CD with/without subacromial decompression and glenohumeral exploration [
7]. Recently, our group demonstrated that good to excellent results can be achieved in 90% of patients with blunt arthroscopic removal of calcific lesions, without performing a subacromial decompression. Therefore, we pursue a minimal-invasive strategy which rather tolerates minor remnant calcifications in favor of rotator cuff integrity [
6]. In the present study, the vast majority of our patients did not present any intraarticular pathologies requiring surgical treatment. If intraarticular pathologies were detected, most likely these lesions did not cause any symptoms. Our results confirm the conclusion of Sirveaux et al., who compared clinical and radiographic outcome in patients with CTS treated either by CD removal alone via an arthroscopic bursal approach or CD removal combined with a standardized glenohumeral exploration [
18]. The authors did not identify a single glenohumeral injury that required surgical treatment. Moreover, duration of postoperative pain and latency of return-to-work were significantly shorter in patients who received CD removal solely compared to patients that underwent CD removal including an additional glenohumeral exploration. After 6-month follow-up, functional outcome and radiographic CD disappearance did not reveal significant differences. Therefore, we agree on the authors’ statement, that a glenohumeral exploration can be avoided as the additional approach might include an increased risk for complications as well as it presumably leads rather to prolonged rehabilitation than clinical benefit. Furthermore, prolonged duration of surgery, increased postoperative pain and subsequently prolonged length of stay potentially cause higher costs [
28,
29]. A glenohumeral exploration may be justified in specific scenarios: I.e. if a relatively large and consistent CD removal has been performed and an intra-articular assessment of the rotator cuff’s integrity is pursued. A thorough evaluation of the rotator cuff (especially of deep layers) may be facilitated by means of arthroscopic visualization. Nevertheless, for the majority of patients with CTS, an additional glenohumeral exploration seems to be an unnecessary and an expandable risk for complications as it contains an additional approach to the joint.
The amount of CD removal is another matter of debate: several authors favor a complete removal of CD while other authors presented good outcome with incomplete excision of CD [
6,
7,
10,
30‐
32]. A total removal of CD may potentially result in a full thickness rotator cuff tear. Evidence is lacking whether an immediate reconstruction or no repair at all leads to superior outcome [
6,
9,
31,
33,
34]. Last but not least, the size and consistency of CD lesions are highly important for the removal of rotator cuff calcifications. In the present study, the vast majority of CD lesions was either tough and tooth paste-like or presented as snowy powder, indicating that an easy removal is feasible without the application of intense forces.
In summary, instead of a standardized glenohumeral exploration within arthroscopic removal of CD lesions, we suggest a patient-specific treatment algorithm, that is individualized on the patient’s presenting complains in order to optimize the risk-benefit-ratio.
Increased risk for complications due to glenohumeral exploration
CTS is predominantly an extraarticular phenomenon rather than a glenohumeral joint disease [
1,
34]. Consequently, we expect an equivalent prevalence of glenohumeral pathologies in patients with CTS compared to healthy subjects. Certainly, an arthroscopic glenohumeral exploration provides the opportunity to detect intraarticular co-pathologies. However, our and previous data demonstrate that intraarticular co-pathologies in patients with CTS were hardly detected and moreover, if an intraarticular pathology was present, this almost never caused any procedural alteration [
18]. Therefore, it is reasonable to question whether an additional glenohumeral arthroscopy can be justified in patients with CTS considering the increased risk for complications such as infection or shoulder stiffness against the lack of a true benefit through arthroscopy [
18]?
The overall risk for complications in shoulder arthroscopy ranges between 4.8% and 10.6% [
35‐
37]. Typical complications in patients having CTS are prolonged pain, secondary adhesive capsulitis, rotator cuff tears, ossifying tendinitis, and osteolysis of the greater tuberosity [
38]. The incidence of a frozen shoulder after shoulder arthroscopy is 2% to 5% in the general population [
39,
40]. Postoperative shoulder stiffness after rotator cuff repair ranges between 4.9% and 32.7% [
41‐
43]. Shoulder stiffness is not well tolerated by patients with CTS; it does not resolve easily and may require long-term rehabilitation [
44]. Reasons for shoulder stiffness are supposed to be the manipulation of capsule and/or residual calcium debris [
6,
34]. Moreover, postoperative shoulder stiffness may be related to rotator cuff tear morphology, postoperative immobilization, glenohumeral adhesion, capsular contracture, or underlying predisposing patient comorbidities [
42,
44,
45]. Reduction of approach-related comorbidity may potentially reduce complication rates and offers the opportunity to perform this procedure as an outpatient surgery that allows for immediate rehabilitation, which subsequently reduces the risk for postoperative stiffness [
18]. Our current rate of postoperative arthrofibrosis is relatively low compared to previous studies – however, if the risk for postoperative arthrofibrosis can be further reduced without performing a glenohumeral approach while at the same time achieving equivalent outcome, one may assume that it might be reasonable to abstain from a glenohumeral exploration in routine fashion when treating patients with CTS arthroscopically [
46]. However, this needs to be further confirmed in prospective comparative investigations.
Furthermore, infection following shoulder arthroscopy is another relevant risk factor. Pauzenberger et al. observed infections following arthroscopic rotator cuff repair in 0.009% [
47]. The authors identified sex (male), age (≥60 years), and length of surgery (≥90 min) to be significantly associated with postoperative infection. Other groups reported overall infection rates after shoulder arthroscopy between 0.03% and 3.4% [
37,
48‐
50]. Especially, joint infections due to Propionibacterium acne (P. acne) are currently controversially discussed in association with shoulder arthroscopy as conventional perioperative antibiotic- or preoperative prophylaxis do not seem to sufficiently decrease the risk for postoperative infections [
47,
51]. Moreover, presurgical skin preparations do not entirely eliminate P. acne [
52‐
54]. Current evidence suggests P. acne being the most frequent identified organism in shoulder infections [
51,
55,
56]. Both, open and arthroscopic surgery provide approach related-opportunities for P. acne to be transferred from skin to deep layers and thus potentially causing glenohumeral joint infections [
57]. Seth et al. observed differences in positive skin cultures contaminated by P. acne that were assessed before skin incision (15.8%) and directly before wound closure (40.4%), which underlines the association between length of surgery and potential risk for surgical side infections [
58]. In order to minimize the risk for infections by P. acne, it is suggested to reduce the size and contamination of surgical approaches [
59]. Due to the fact that glenohumeral joint infections are associated with disability and significant direct and indirect socioeconomic costs, we suggest to perform a glenohumeral joint exploration only if an intraarticular injury that requires surgical treatment is highly expected.
In general, the impact of glenohumeral exploration within arthroscopic removal of calcifications in CTS remains an under-investigated issue. To date, postoperative pain and latency of return-to-work were found to be significantly shorter in patients who received CD removal solely compared to patients that received an additional glenohumeral exploration [
18]. It is reasonable that any additional manipulation/invasive maneuver during shoulder surgery might affect the clinical and/or functional outcome and potentially increases the likelihood of complications since this has already been demonstrated in various other surgical procedures [
13,
37,
60,
61]. Investigations comparing complications of different arthroscopic approaches have not been performed yet. Sufficient data exist on 30-day readmission rates as well as risk factors for postoperative complications following shoulder arthroscopy as described by Shields et al. [
45]. The authors found shoulder arthroscopy to have a 1% thirty-day complication rate. Age ≥ 60 years, operating room (OR) time ≥ 90 min, chronic obstructive pulmonary disease, inpatient status, disseminated cancer, and nicotine abuse are risk factors for postoperative complications [
60]. These results have been confirmed by other authors such as Moody et al. who demonstrated, that prolonged operative time, more invasive and/or additional surgical approaches increase the risk for complications as well as health care expenditures [
29,
60].
In the present study, intraarticular pathologies that needed surgical treatment have only been observed in few patients. For the majority of patients with CTS, an additional glenohumeral exploration might be an unnecessary risk and would most likely not translate into a clinical benefit. As patients undergoing surgery in CTS already reflect a “negative selection” due to failed conservative treatment, a reasonable risk-benefit-ratio by means of minimal approach-related comorbidity and perioperative risk for complications should be pursued. As there is currently no evidence supporting that patients with CTS benefit from glenohumeral explorations during arthroscopic removal of calcifications, the additional glenohumeral approach should only be performed in case of founded suspicion of relevant concomitant intraarticular pathologies.
Limitations and strength
The retrospective study design is associated with certain limitations, such as loss of information (missing reports), heterogeneous preoperative conservative treatment, and unequal group power (i.e. gender, affected shoulder, etc.). Additionally, functional and clinical outcome data was not implemented into this study. Moreover, this study was of descriptive nature and did not include a control group. Nevertheless, as far as we are aware, there is no previous study specifically investigating intraarticular glenohumeral pathologies during CD removal in patients with calcifying tendinitis. Furthermore, a huge advantage of the present study is that all patients were treated by the same orthopedic surgeon resulting in high consistency and homogeneous evaluation of intraarticular conditions.