case report

Paralabial Cyst and Microinstabily: A Case Report

Vincenzo Morea1*, M. I. Borruto2, Guido Zattoni1, Flavio Terragnoli1, Francesco Benazzo1

1Fondazione Poliambulanza, Brescia, Italy

2Università Cattolica del Sacro Cuore, Roma, Italy

*Corresponding author: Vincenzo Morea, Fondazione Poliambulanza, Brescia, Italy

Received Date: 1 September 2022

Accepted Date: 5 September 2022

Published Date: 7 September 2022

Citation: Morea V, Borruto MI, Zattoni G, Terragnoli F, Benazzo F (2022) Paralabial Cyst and Microinstabily: A Case Report. Ann Case Report 7: 934. DOI:


Gleno-humeral joint instability has been traditionally divided in two categories: TUBS (traumatic unidirectional Bankart lesion, responds to surgery) and AMBRII (atraumatic, multidirectional, bilateral, responds to rehabilitation, inferior capsular shift, and interval closure). In patients with TUBS, the common imaging finding are Bankart lesion, Hill-Sachs lesion; in AMBRI, there is no evident structural lesions. This classification is still noteworthy, however micro instabilities, common in overhead athletes or patients who return to sport after a period of standstill, cannot be classified strictly as one of these categories. For this reason, classifications have been uploaded with further two groups regarding instabilities: AIOS (acquired instability in overstressed shoulder, surgery) and AMSI (Atraumatic minor shoulder instability) [1].

Keywords: Paralabial cyst; Infiltrative therapy


In literature there are few cases reported of AMSI, only patients complaining shoulder pain after a standstill period. One of the most frequent causes of AIOS is posterior-superior impingement (PSI).

Case Report

A 42-year-old male, manual worker comes to our clinic complaining chronic dominant shoulder pain. Nor history of fractures, neither dislocation. His pain did not improve nor after infiltrative therapy, neither after physical therapies. At clinical examinations, no deformities are reported, and ROM overlap the contralateral side. No neurological deficits or muscular atrophy is found. Neer, Howkins and Jobe test are positives [2].

There is no sign of shoulder instability. Shoulder pain occur when the arm is in abduction and retropulsion, related to the repetitive overhead microtraumas. MRI shows blurred T2 hyperintense-signal area relatable to bone oedema in the posteroinferior side of the humeral head, which also appears to be disrupted (Figure 2), anterior paralabial cysts (Figure1) and supraspinous, disrupted (Figure 3). MRI shows an AIOS pattern of micro instability due to repetitive traumas in overhead workers.

Figure 1: Paralabial cyst in T2-w MRI.