J. Romero et al., Scapular neck fracture - the influence of permanent malalignment of the glenoid neck on clinical outcome, ARCH ORTHOP, 121(6), 2001, pp. 313-316
A scapular neck fracture is considered unstable if it is associated with an
ipsilateral clavicular fracture or an acromioclavicular (AC) joint disloca
tion. Currently, it is recommended that stabilization of a disrupted should
er girdle must be achieved through open reduction and internal fixation of
the clavicular fracture or by reduction of the AC joint, without addressing
the scapular neck. However, if the displaced glenoid neck is not simultane
ously reduced, malalignment of the glenoid neck may persist. The purpose of
this retrospective study was to analyze the effect of associated shoulder
girdle injury on glenoid displacement and the influence of glenoid malalign
ment on clinical outcome. Nineteen patients with scapular neck fractures we
re reviewed clinically and radiologically at a mean of 8 years (range 2-21
years) after injury. None of them has developed nonunion of the scapular ne
ck, and only one showed radiological signs of mild degenerative joint disea
se. The glenopolar angle (GPA), which assesses the rotational malalignment
of the glenoid about an anteroposterior axis perpendicular to the scapular
plane on plain X-rays was measured less than 20 degrees in six patients. Th
ree of them had sustained an associated clavicular fracture or AC joint dis
location. The other 3 patients had permanent severe malalignment of the gle
noid neck in the absence of an associated shoulder girdle injury. Five pati
ents with GPA less than 20 degrees complained of moderate or severe pain, w
hereas of the 13 patients with mild or no glenoid rotational displacement o
r medial displacement alone, 11 patients had no or mild pain, and only 2 ha
d moderate or severe pain (P = 0.0095). Five patients presented with reduce
d activities of daily living, 4 of them had severe glenoid rotational displ
acement (P = 0.0173). Loss of motion was found in only 2 patients, and both
had a severely displaced glenoid neck (P = 0.088). In conclusion, severe d
isplacement of the glenoid neck may occur with or without associated fractu
re of the clavicle or dislocation of the AC joint and can be identified as
a GPA less than 20 degrees. Scapular neck fractures with such malalignment
have a less favorable long-term outcome compared with otherwise comparable
cases with absence of glenoid malalignment as measured with the glenopolar
angle.