Treatment of acromioclavicular joint separations in Japan: a survey.

BACKGROUND: Treatment options for acromioclavicular joint (ACJ) separations are highly dependent on severity, as well as the patient's background. Furthermore, some patients can be switched from conservative to surgical treatment. In this study, we conducted a mail-based questionnaire survey of members of the Japan Shoulder Society on the administration of treatments for ACJ separations.
METHODS: A questionnaire survey with 5 categories was mailed to all 1655 members of the Japan Shoulder Society (including 59 councilors): initial treatment, whether surgery was performed, indications for surgery based on severity, switching from conservative to surgical treatment, and surgical methods.
RESULTS: Altogether, 183 members, including 56 councilors, responded. Regarding the initial treatment, 17 respondents opted for treatment without immobilization or fixation and 166 opted for immobilization or fixation. Of the members, 11 opted for only conservative treatment whereas 172 chose surgery depending on the case; of the latter, 9 considered it for patients with a Rockwood classification of type 2 or higher; 120, for patients with type 3 or higher; and 172, for patients with types 4-6. Furthermore, 75 of 172 members had experience switching to surgical treatment during conservative treatment. For 64 of 172 members, the modified Cadenat method was the most common surgical method.
CONCLUSIONS: Only 11 members opted for conservative treatment of ACJ separations, and approximately 95% of physicians chose surgery. Furthermore, >70% of physicians considered surgery for an injury classified as type 3 or higher, and 37% of members performed the modified Cadenat method. However, the popularization of arthroscopic surgery may affect the selection of surgical methods in the future.

The choice of treatment for acromioclavicular joint (ACJ) separations is highly dependent on severity, as well as the patient’s background. Even for shoulder surgery specialists, there is no gold-standard concept for the initial treatment, indications for surgery, and surgical methods for acute injuries. Furthermore, some patients can be switched from conservative to surgical treatment over the course of the injury. The Tossy classification or Rockwood classification is commonly used to classify the severity of ACJ separations; however, the classification method for determining the severity of surgery is not standardized. In this study, we conducted a mail-based questionnaire survey of delegates and members of the Japan Shoulder Society (JSS) on the administration of treatments for acute injuries with ACJ separations.

Methods

We conducted a mail-based questionnaire survey of all 1655 JSS members (comprising 1596 regular members and 59 councilors as of January 2018) regarding the treatment of patients with acute ACJ separations for which consultations occurred within 2 weeks after injury. The survey items consisted of 5 categories: initial treatment, whether surgery was performed, indications for surgery based on severity, whether patients had changed from conservative to surgical treatment over the course of the injury, and surgical methods (Table I, Table II, Table III, Table IV). The Tossy or Rockwood classification was used to represent severity., For convenience, however, a grade 1 injury according to the Tossy classification was defined as a type 1 injury according to the Rockwood classification; grade 2, as type 2; and grade 3, as type 3 or higher. In this study, we used the Rockwood classification to represent severity for all ACJ separations.

Table I

Treatment methods

A: Choice of treatment method ① Perform conservative treatment for all ② Perform surgery based on the case B: Initial treatment ① No fixation ② Sling fixation ③ Sling fixation + bust bandage ④ Brace fixation ⑤ Other ()∗ C: Fixation duration if fixated (weeks) ① Sling fixation (Fixation period: 1/2/3/4/5/6) ② Sling fixation + bust bandage (Fixation period: 1/2/3/4/5/6) ③ Brace fixation (Fixation period: 1/2/3/4/5/6) D: Was there any change to surgery during the course of conservative treatment?• No • Yes E: When the course of conservative treatment was switched to surgery• Period from injury to surgery ()∗ • Reason for changing to surgery ()∗

Respondents were asked to provide fill-in-the-blank responses.

Table II

Indications for surgery based on severity (Rockwood or Tossy classification)∗

Rockwood classification

Type I

Type II

Type III

Type IV

Type V

Type VI

Tossy classification

Type I

Type II

Type III

Multiple answers were allowed.

Table III

Factors for surgery other than severity∗

Gender

Hand dominance

Occupation

Occupations to actively consider ()†

Sporting activities

Sporting activities to actively consider ()†

Others()†

Multiple answers were allowed.

Respondents were asked to provide fill-in-the-blank responses.

Table IV

Expected effects of surgery∗

Early rehabilitation

Prevention of osteoarthritis of the ACJ

Prevention of muscle weakness

Prevention of a restricted range of motion of the joints

Prevention of scapulothoracic joint dysfunction

Others ()†

ACJ, acromioclavicular joint.

Multiple answers were allowed.

Respondents were asked to provide fill-in-the-blank responses.

Results

The respondents comprised 56 of 59 councilors of the JSS (response rate, 94.9%) and 127 of 1596 regular members (response rate, 8.0%), for a total of 183 respondents. A response rate > 90% was obtained among the shoulder surgeons (JSS councilors) who play a leading role in the JSS.

In terms of treatment options, 11 members opted for only conservative treatment in all cases and 172 members chose surgical treatment depending on the individual case. For the initial treatment, 17 members opted for treatment without immobilization or fixation; 142, treatment with a fixed upper-limb sling; and 24, treatment with a fixed orthosis for holding the shoulder joint. In the immobilization period, the length of sling fixation of the upper limb was 1 week for 10% of members (n = 14), 2 weeks for 36% (n = 51), 3 weeks for 42% (n = 59), 4 weeks for 4% (n = 6), and ≥1 month for 8% (n = 12), whereas the length of orthosis fixation was 3 weeks for 58% of members (n = 14) and 4 weeks for 42% (n = 10).

Among the 172 members who suggested the possibility of surgery, 9 considered it for patients with a Rockwood classification of type 2 or higher; 120, for type 3 or higher; and 172, for types 4-6 (Fig. 1). Factors other than severity on which the members focused regarding surgical indications were occupation (67%, n = 116), sports activity (52%, n = 91), and sex (33%, n = 56). Of the 116 members considering a patient’s occupation, in particular, 41 considered surgical indications to include carpenters, plasterers, and teachers (occupations requiring shoulder-raising positions); 28, civil engineering workers (including workers heavy handling heavy loads); 13, farmers; 2, fishers; 2, Self-Defense Forces personnel; 1, dentists; and 1, delivery workers. Furthermore, 108 members (61.4%) conducted surgery to prevent scapulothoracic joint dysfunction; 93 (52.8%), to prevent apparent deformity of the ACJ; 77 (43.8%), to prevent muscle weakness; 36 (20.5%), for early rehabilitation; 29 (16.5%), to prevent joint range-of-motion restriction; and 14, for other reasons.

Figure 1

Indications for surgery based on severity (9 members considered surgery for type 2 or higher; 120 members, for type 3 or higher; and 172, for types 4-6).

During conservative treatment, 75 of the 172 members had experience switching to surgical treatment, excluding the 11 members who consistently performed conservative treatment. Of these members, 20 (26.7%) made the switch within 1 month; 28 (37.3%), within 1-3 months; 8 (10.7%), within 3-6 months; 9 (12%), within 6 months to 1 year; and 1 (1.3%), after 1 year. The reason for surgery was pain (n = 39, 52%), patient’s wishes (n = 16, 21.3%), fatigue of the shoulder girdle (n = 7, 9.3%), posterior instability of the ACJ (n = 5, 6.7%), postural problems (n = 5, 6.7%), worsening of severity (n = 3, 4%), limited range of motion (n = 2, 3%), or stiff shoulder (n = 1, 1%).

The surgical methods to be selected were roughly classified into open surgery and arthroscopic surgery (including some overlap; Fig. 2). Forty-eight members performed arthroscopic surgery for coracoclavicular ligament reconstruction, whereas 34 members performed arthroscopic coracoclavicular ligament reconstruction plus acromioclavicular ligament and deltoid muscle repair. Regarding open surgery, 67 members performed the modified Cadenat method (regardless of internal fixation material); 31, coracoclavicular ligament reconstruction; 29, hook plate fixation; 27, the modified Phemister method; 25, distal clavicle resection; 24, coracoclavicular ligament reconstruction plus acromioclavicular ligament and deltoid muscle repair; 15, the Weaver-Dunn method; 12, ACJ fixation with K-wires; 11, the hook plate method plus conoid ligament reconstruction; 6, the Bosworth method; 3, the modified Dewar method; and 3, the modified Neviaser method.

Figure 2

Surgical methods performed by 172 members. CCL, coracoclavicular ligament; ACL, acromioclavicular ligament; ACJ, acromioclavicular joint.

Discussion

In this study, we mailed a questionnaire survey with questions about the classification of ACJ separation severity to the members of the JSS. The questionnaire was sent to all 1655 JSS members, and 183 (11.1%) responded. Although the overall response rate was low, 56 of 59 councilors—who had >10 years of clinical experience as shoulder surgeons and were in leadership positions at the JSS at the time of the survey—responded. This provided us with very significant results.

In terms of surgical indications,,, Rockwood classification types 1 and 2 generally indicate conservative treatment whereas types 4-6 indicate surgical indications; type 3 is controversial.,, However, Song et al reported that 17 patients with type 2 injuries that had been treated conservatively during the 9 years since 1998 underwent surgical treatment of an old ACJ injury because pain and ACJ instability remained. A type 2 injury is ACJ subluxation, and the pathology is rupture of the ACJ capsule and rupture of the acromioclavicular ligament. It is thought that continuity is maintained although there is partial damage to the coracoclavicular ligament. However, Takase observed ruptures of the ACJ capsule, acromioclavicular ligament, and trapezoid ligament with an intact conoid ligament in all cases with type 2 injuries evaluated by magnetic resonance imaging within 3 days after injury. According to our results, 9 of 172 members suggested that a type 2 injury was indicative of surgery even in acute cases. Considering the simultaneous tearing of the acromioclavicular and trapezoid ligaments, all type 2 injuries should not consistently be considered for conservative treatment because posterior instability of the ACJ might remain. Sufficient follow-up is necessary, and surgical treatment may be required depending on the symptoms. However, regarding the main factors other than severity, occupation was more important than sports activity to 116 of 172 respondents (67%). Occupations such as plastering, carpentry, teaching, and farming, which require patients to maintain positions with the upper limbs raised, were regarded as important. This finding was consistent with the prevention of scapulothoracic joint dysfunction, expected from surgery.

Song et al reported the importance of conducting surgery within 3 weeks of injury to achieve a successful outcome. Furthermore, in our study, 75 of 172 members had considered a switch to surgical treatment during conservative treatment, with 64% of respondents switching within 3 months and 99% switching within 1 year. The reasons for opting for surgery included the wishes of patients (about 20% of members who switched); however, about 50% indicated that painful symptoms were the reason. Although it was difficult to evaluate the severity and therapeutic results of patients who were switched from conservative treatment to surgical treatment through the questionnaire survey, the reason for the switch was that the pain in the distal clavicle remained during shoulder movements.

Various surgical methods exist for ACJ separations, and relatively good results have been reported. Typical open surgery methods include the Phemister method or Neviaser method to repair the acromioclavicular ligament, the Bosworth method for inter-coracoclavicular fixation, the Weaver-Dunn method or Cadenat method using the coracoacromial ligament as a substitute ligament for the coracoclavicular ligament, and the Dewar method for treatment by dynamic stabilization with the conjoined tendon. In contrast, Salzmann et al, Scheibel et al, Balog et al, De Beer et al, and Takase and Yamamoto have reported methods for anatomically reconstructing the trapezoid and conoid ligaments with arthroscopic surgery. Furthermore, Scheibel et al reported that posterior instability of the ACJ may remain with vertical stabilization alone and it is important to reconstruct the acromioclavicular ligament simultaneously, which reduces posterior instability. According to the results of our questionnaire, 67 of 172 members performed the modified Cadenat method (Figs. 3 and 4), which is an open operation. However, in recent years, owing to the advancement of arthroscopic technology, 48 of 172 members have been performing arthroscopic coracoclavicular ligament reconstruction; only 34 of these have added reconstruction of the acromioclavicular ligament to arthroscopic coracoclavicular ligament reconstruction.

Figure 3

Surgical procedure by modified Cadenat method. Preparation of the transferred ligament is shown on the left: osteotomy of the anterior edge of the acromion with the coracoacromial ligament (A), lateral edge of the coracoacromial ligament (B), and medial edge of the coracoacromial ligament (C). Fixation of the transferred ligament to the clavicle is shown on the right. Release of the coracoacromial ligament is performed with a bone tip from the acromion (B-A-C). The detached coracoacromial ligament with the bone tip is fixed to the anterior side of the clavicle using a screw with a spike washer in a position that allows sufficient tension to be obtained.

Figure 4

Representative case: 29-year-old male patient. (A) Preoperative radiograph. (B) Postoperative radiograph.

Our study had several limitations. Given the low survey response rate, these findings may not be generalizable to the interventional community as a whole. However, a response rate of >90% was obtained among the shoulder surgeons (JSS councilors) who play a leading role in the JSS. Furthermore, the results of this study did not clearly show why treatment was switched from conservative to surgical and delineate the choice of surgical procedure when transitioning to address old ACJ injuries. In addition, the effect of severity on the choice of surgical methods could not be examined.

Conclusion

For the treatment of ACJ separations, only 11 members performed conservative treatment regardless of severity and approximately 95% of respondents performed surgery as appropriate. Furthermore, >70% of members considered a Rockwood classification of type 3 or higher as an indication for surgery, and 37% of the total respondents chose the modified Cadenat method. However, the selection of surgical methods may change in the future owing to the popularization of arthroscopic surgery.

Disclaimer

The authors, their immediate families, and any research foundations with which they are affiliated have not received any financial payments or other benefits from any commercial entity related to the subject of this article.