Neglected Anterior Dislocation of Shoulder: is surgery necessary? A Rare Case with review of literature.

INTRODUCTION: Shoulder joint is the most frequently dislocated joint. However, it is rarely neglected and treatment is sought immediately. Delayed or neglected shoulder dislocations are difficult to manage and require extensive procedures to obtain good functional outcome. Very few cases are described in literature showing neglected shoulder dislocation with good functional range of movement. We report a case with 3 years of neglected anterior shoulder dislocation with preserved joint function. CASE REPORT: A 40 years old gentleman presented withfracture distal end of the radius (left). On clinical examination we observed that he had anterior dislocation of his left shoulder which was confirmed on radiographic evaluation. He had history of seizures 3 years back, which may be the cause of dislocation which went unnoticed. On examination he had good range of motion without any pain. Patient could perform all routine activities with no major functional limitation. At three years after dislocation CT Scan showed neocavity formation.
CONCLUSION: Neglected shoulder dislocation with preserved joint function without major functional limitation is a rare presentation. This condition should be kept in mind in patients with history of seizures. Proper evaluation and counseling of patients avoids extensive procedures and avoids complications of surgery. Observation can be a treatment option in patients with preserved range of movement especially involving non dominant handand having low functional demand. This report presents rare presentation of neglected shoulder dislocation highlighting its natural history and its outcome following conservative treatment.

Introduction

Shoulder joint is the most frequently dislocated joint. Anterior shoulder dislocation constitutes 95% of all shoulder dislocations, mainly caused by trauma and posterior dislocation is caused by indirect trauma like violent muscular contractions seen in epileptic attack and electrocution. Unilateral shoulder dislocation is most common constituting 85% of all dislocations [1, 2]. Because of its typical presentation, it is rarely missed. Neglected shoulder dislocation presents with gross limitation of shoulder function and requires extensive procedures to obtain desired outcome. Also, there are many pathological changes in bony and soft tissue architecture in shoulder joint in case of neglected dislocations [3,4]. We present a rare case of anterior dislocation of shoulder following a seizure attack with preserved joint functions and no major functional limitation of joint function. In this report we bring this rare presentation of neglected shoulder dislocation highlighting its natural history and its outcome following conservative treatment.

Case presentation

A 31 years old right hand dominant gentleman presented to our orthopedic specialty clinic with fracture distal end radius on left side. On further evaluation, there was deformity in ipsilateral shoulder joint and asymmetry was present as compared to opposite side. There was an anterior globular bony swelling palpable with well defined margins. Transmitted movements from humerus were present confirming it to be bony humeral mass. There was wasting of deltoid muscle as compared to opposite side. Range of motion were flexion upto 170 degrees (Fig 1A), extension up to 10 degree (Fig 1B), internal rotation up to L3 (Fig 1C), and external rotation up to 30 degree (Fig 1D) and abduction up to 120 (Fig 1E) in both active and passive movements, further movements were restricted and mildly painful. Patient did not have any history of significant trauma to shoulder in past. However he gave a history of seizure attacks three years back following which he had shoulder pathology. He had taken antiepileptic treatment; however no treatment was taken for the shoulder. There were no further epileptic episodes and he was taking antiepileptic treatment. Radiographs of shoulder joint were taken which confirmed anteriorly dislocated humeral head (Figure 2). Further views of shoulder joint were taken to check for any bony changes. They didn’t show any significant abnormality. CT scan showed anteroinferior dislocation with neocavity with pseudojoint formation (Fig.3A,3B,3C). Chronic hillsachs lesion was also seen. MRI Scan showed anteroinferior shoulder dislocation with intact rotator cuff muscles (Fig.4A,4B) Since the patient had good functional range of movement we explained him the treatment options. He opted for non surgical line of management. Hence was given shoulder mobilization exercises. Presently patient is being followed up with no fresh complaints and maintained join movements.

Figure 1

(a,b,c,d & e): Clinical photographs showing functional range of movement of shoulder joint

Figure 2

Radiograph of joint showng anteroinferior dislocation of shoulder joint

Figure 3

(a,b,c & e): CT Scan showing anteroinferior dislocation with neocavity formation.

Figure 4

(a & b): MRI scan showing anteroinferior dislocation with intact rotator cuff muscles

Anterior dislocation of shoulder unlike posterior dislocation is most commonly traumatic in nature. The mechanism of anterior dislocation following trauma is that greater tuberosity abuts against acromion when arm is abducted and extended, causing leverage forces leading head to come out of glenoidcavity [5]. Posterior dislocation secondary to seizure attack is caused due to imbalance between strong internal rotators and weak external rotators and deltoid. The cause of anterior dislocation following seizure is postulated to be direct trauma due to collapse of patient hitting the floor [6]. Anterior dislocation of shoulder is commonly missed after seizure because of its unusual occurrence, post seizure drowsiness and subsequent medical management[5].

The term chronic dislocation of shoulder is applied to condition where there is loss of recognition of injury for at least 3 weeks [7] or 4weeks [8]. Many authors have described chronic dislocation with varying amount of duration at presentation. Rowe and Zarin presented eight patients with anterior dislocation with seven patients presenting at 3 week to 2 year interval and one patient at 10 year duration [7]. Goga presented 31 patients with chronic anterior dislocation with longest duration of failed recognition at 2 years [9]. Postacchini and Facchini presented five patients with 6 weeks as longest duration of failure of diagnosis[10].

Mansat et al showed five patients with 6 weeks to 3 years as the duration of missed diagnosis[11]. Mancini et al presented a case with 24 years of missed anterior shoulder dislocation [12]. Our case presented 10 years after the dislocation.

Treatment options for neglected shoulder dislocation include observation, manipulation, open reduction with or without allograft reconstruction, bankarts repair, capsulolabial repair and arthroplasty [7, 13]. Surgical treatment for chronic dislocations is usually advocated for better functional outcome, however the results can be poor and unsatisfactory[12].

Very few cases describe chronic dislocation of shoulder with good functional range of motion which were treated nonsurgically. Table shows epidemiological details of patients reported with asymptomatic neglected anterior shoulder dislocation. Essi et al showed a case with 15 years old neglected anterior shoulder dislocation in a 35 year old lady with good functional range of movement and neocavity formation leading to preserved movements [14]. Similar neocavity formation seen in a case described by Mancinni et al with 24 years of neglected dislocation ion a 74 year old lady with low functional demand [12]. Jerosch et al [3] presented a case of a young male with preserved movements 4 years after missed diagnosis. This case didn’t show neocavity formation, but had a large Hill Sachs lesion which locked the head in dislocated position. In our case we found neocavity formation with large hill Sachs lesion.

Conclusion

Thus, we conclude that neglected shoulder dislocation after many years eventually leads to neocavity formation. Observation can be an option if patient presents late and surgical treatment is likely to have unsatisfactory results. Low demand patient with involvement of non dominant hand can be observed with good functional outcome.

Neglected shoulder dislocation can present with neocavity formation and preserved joint function. In such cases, observation can be a treatment option especially when surgical option gives unsatisfactory result. This is particularly important in a patient with low demand occupation and nondominant hand.