Dislocation of the acromioclavicular joint is one of the most common shoulder injuries
in a sport‐active population. The question of whether surgery should be used remains
controversial. This is an update of a Cochrane Review first published in 2010. To
assess the effects (benefits and harms) of surgical versus conservative (non‐surgical)
interventions for treating acromioclavicular dislocations in adults. We searched the
Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (to June 2019),
the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library
2019, Issue 6), MEDLINE (1946 to June 2019), Embase (1980 to June 2019), and LILACS
(1982 to June 2019), trial registries, and reference lists of articles. There were
no restrictions based on language or publication status. We included all randomised
and quasi‐randomised trials that compared surgical with conservative treatment of
acromioclavicular dislocation in adults. At least two review authors independently
performed study screening and selection, 'Risk of bias' assessment, and data extraction.
We pooled data where appropriate and used GRADE to assess the quality of evidence
for each outcome. We included five randomised trials and one quasi‐randomised trial.
The included trials involved 357 mainly young adults, the majority of whom were male,
with acute acromioclavicular dislocation. The strength of the findings in all studies
was limited due to design features, invariably lack of blinding, that carry a high
risk of bias. Fixation of the acromioclavicular joint using hook plates, tunnelled
suspension devices, coracoclavicular screws, acromioclavicular pins, or (usually threaded)
wires was compared with supporting the arm in a sling or similar device. After surgery,
the arm was also supported in a sling or similar device in all trials. Where described
in the trials, both groups had exercise‐based rehabilitation. We downgraded the evidence
for all outcomes at least two levels, invariably for serious risk of bias and serious
imprecision. Low‐quality evidence from two studies showed no evidence of a difference
between groups in shoulder function at one year, assessed using the Disability of
the Arm, Shoulder, and Hand questionnaire (DASH) (0 (best function) to 100 (worst
function)): mean difference (MD) 0.73 points, 95% confidence interval (CI) −2.70 to
4.16; 112 participants. These results were consistent with other measures of function
at one‐year or longer follow‐up, including non‐validated outcome scores reported by
three studies. There is low‐quality evidence that function at six weeks may be better
after conservative treatment, indicating an earlier recovery. Very low‐quality evidence
from one trial found no difference between groups in participants reporting pain at
one year: risk ratio (RR) 1.32, 95% CI 0.54 to 3.19; 79 participants. There is very
low‐quality evidence that surgery may not reduce the risk of treatment failure, usually
resulting in non‐routine secondary surgery: 14/168 versus 15/174; RR 0.99, 95% CI
0.51 to 1.94; 342 participants, 6 studies. The main source of treatment failure was
complications related to surgical implants in the surgery group and persistent symptoms,
mainly discomfort, due to the acromioclavicular dislocation in the conservatively
treated group. There is low‐quality evidence from two studies that there may be little
or no difference between groups in the return to former activities (sports or work)
at one year: 57/67 versus 62/70; RR 0.96, 95% CI 0.85 to 1.10; 137 participants, 2
studies. Low‐quality but consistent evidence from four studies indicated an earlier
recovery in conservatively treated participants compared with those treated with surgery.
There is low‐quality evidence of no clinically important difference between groups
at one year in quality of life scores, measured using the 36‐item or 12‐item Short
Form Health Survey (SF‐36 or SF‐12) (0‐to‐100 scale, where 100 is best score), in
either the physical component (MD −0.63, 95% CI −2.63 to 1.37; 122 participants, 2
studies) or mental component (MD 0.47 points, 95% CI −1.51 to 2.44; 122 participants).
There is very low‐quality and clinically heterogenous evidence of a greater risk of
an adverse event after surgery: 45/168 versus 16/174; RR 2.82, 95% CI 1.65 to 4.82;
342 participants, 6 studies; I 2 = 48%. Common adverse outcomes were hardware complications
or discomfort (18.5%) and infection (8.7%) in the surgery group and persistent symptoms
(7.1%), mainly discomfort, in the conservatively treated group. The majority of surgical
complications occurred in older studies testing now‐outdated devices known for their
high risk of complications. The very low‐quality evidence from one study (70 participants)
means that we are uncertain whether there is a between‐group difference in patient
dissatisfaction with cosmetic results. It is notable that the evidence for function,
return to former activities, and quality of life came from the two most recently conducted
studies, which tested currently used devices and interventions in clearly defined
participant populations that represented the commonly perceived population for which
there is uncertainty over the use of surgery. There were insufficient data to conduct
subgroup analysis relating to type of injury and whether surgery involved ligament
reconstruction or not. There is low‐quality evidence that surgical treatment has no
additional benefits in terms of function, return to former activities, and quality
of life at one year compared with conservative treatment. There is, however, low‐quality
evidence that people treated conservatively had improved function at six weeks compared
with surgical management. There is very low‐quality evidence of little difference
between the two treatments in pain at one year, treatment failure usually resulting
in secondary surgery, or patient satisfaction with cosmetic result. Although surgery
may result in more people sustaining adverse events, this varied between the trials,
being more common in techniques such as K‐wire fixation that are rarely used today.
There remains a need to consider the balance of risks between the individual outcomes:
for example, surgical adverse events, including wound infection or dehiscence and
hardware complication, against risk of adverse events that may be more commonly associated
with conservative treatment such as persistent symptoms or discomfort, or both. There
is a need for sufficiently powered, good‐quality, well‐reported randomised trials
of currently used surgical interventions versus conservative treatment for well‐defined
injuries. Surgical versus conservative for treatment for acromioclavicular dislocations
of the shoulder in adults This is a summary of research on the effects of surgery
compared with non‐surgical (conservative) treatment methods to treat a dislocated
acromioclavicular joint. Background The acromioclavicular joint is located at the
top of the shoulder. It is the joint between the collarbone and the acromion (a projection
from the shoulder blade that is located at the point of the shoulder). Acromioclavicular
joint dislocation is one of the most common shoulder injuries treated in a sport‐active
population. It is a common shoulder injury in cyclists and contact sports players
such as footballers, boxers, and martial arts practitioners. The dislocation typically
occurs in young men who fall and suffer a direct impact to the top of the shoulder.
Most acromioclavicular dislocations are treated without surgery, especially those
with less severe separation between the bones. Non‐surgical or conservative treatment
involves immobilisation of the arm. However, the outcome can be less satisfactory
when a more serious dislocation occurs. Surgical treatments involve repositioning
the joint parts and repairing or reconstructing the ruptured ligaments. Results of
the search We searched medical databases up to June 2019 and included six trials involving
357 participants who were mainly young male adults. All studies compared surgical
fixation (using either screws, plates, pins, or other devices to stabilise the dislocated
joint) with a conservative method (immobilisation with one of three types of slings
or a specially designed splint). In all trials the arm was also supported in a sling
or similar device after surgery. Where described, both groups had exercise‐based rehabilitation.
Key results We found that surgery compared with conservative treatment may not improve
shoulder function, return to former activities (sport and work), or quality of life
at one year. We found evidence that at six weeks, these outcomes may be better after
conservative treatment, indicating an earlier recovery. It is unclear whether there
is a difference between surgery and conservative treatment in pain at one year, treatment
failure usually resulting in secondary surgery, or patient unhappiness with their
shoulder appearance. The review found more complications in the surgery group, which
were mainly related to the surgical hardware or infection from the surgery. In contrast,
complications in the conservatively treated group were mainly discomfort. The risk
of such complications varied amongst the six studies and is likely to depend on the
type of surgery used. Surgical complications were more common in the older trials,
which used types of surgery rarely used today. Quality of the evidence All six studies
had weaknesses that could affect the reliability of their results. We considered the
evidence for all outcomes to be either of low or very low quality. Conclusions Low‐quality
evidence indicates that surgery may not provide benefits at one year over conservative
treatment for acromioclavicular dislocations in adults. Further good‐quality studies
may help resolve this uncertainty and change these conclusions.