MRI of shoulder instability

The most unstable joint in the body, the glenohumeral joint is subject to many insults including microinstability, subluxation and dislocation. During the last two decades, MRI has allowed for direct visualization of many of the lesions related to instability, aiding in diagnosis as well as therapeutic planning and follow-up. This article reviews the use of MRI for shoulder instability and describes the different types of lesions associated with this disorder. Topics include technical considerations, the use of MR arthrography, normal anatomy and variants, labral and glenohumeral ligament pathology, and osseous lesions related to instability.     

Developments in Bankart repair for treatment of anterior instability of the shoulder

In the past 10 years, Bankart repair for operative treatment of recurrent luxation of the shoulder has become well established. Recently, the arthroscopic Bankart procedure has been developed. Since 1991, cannulated, bioabsorbable plugs are being used (Suretac; Acufex Microsurgical, Mansfield, Ma., USA). This investigation examines what the advantages of this micro-invasive technique are compared with the open Bankart procedure. From 1986 to 1995, 120 patients underwent Bankart repair of the shoulder in our hospital. Since 1993 we have preferred using arthroscopy, and since 1994 with Suretac. We were able to follow-up 93 patients. The results were assessed using the criteria of stability, range of motion, pain and functional results. The patients were evaluated using the Rowe score. The mean follow-up time was much shorter in the arthroscopic group. Nevertheless, we registered a higher reluxation rate (2 patients, 8%) in comparison with the group that underwent open surgery (3 patients, 4%). As postoperative pain and deterioration of range of motion are less, however, the mean Rowe score shows no significant difference. In conclusion, proper selection of patients has to be performed: arthroscopic Bankart repair is recommended for refixation of a detached anterior labrum. It is disadvantageous when the labrum is degenerated or the capsular tissue is attenuated. That is why, in our opinion, the open Bankart procedure with its capsulorrhaphy cannot be renounced completely.     

Posterior bone block procedure for posterior shoulder instability

The posterior bone block procedure is an uncommon surgical procedure used in the treatment of posterior shoulder instability. The purpose of this study is to report the results of the posterior bone block procedure in the treatment of posterior shoulder instability. We retrospectively reviewed 21 shoulders that had undergone a posterior bone block procedure in the treatment of recurrent posterior shoulder instability between 1984 and 2001. Fifteen patients (16 shoulders) had a prior traumatic posterior glenohumeral dislocation and 5 patients (5 shoulders) had a prior traumatic posterior glenohumeral subluxation. The mean age at surgery was 24.8 years (range 17–40 years). Patients were evaluated with the Constant score, the Duplay score, a subjective result, and radiography. Preoperatively, ten shoulders had glenoid fractures, two shoulders had loss of the normal contour of the posterior osseous glenoid, and ten shoulders had humeral head impaction fractures (reverse Hill-Sachs lesion). Seventeen shoulders underwent preoperative computed tomography and had average glenoid retroversion of 9.6° (range 0–21°). At an average follow-up of 6 years, all patients reported their subjective results as good or excellent. At follow-up the mean Constant score was 93.3 points (range 80–103 points), and the mean Duplay score was 85.6 points (range 40–100 points). Fifteen patients returned to sports at their pre-injury level. Three patients were considered clinical failures; one with a recurrent posterior dislocation and two with substantial posterior apprehension on follow-up examination. Two shoulders had glenohumeral arthritis on radiographs at the latest follow-up. The posterior bone block is a good treatment option for posterior dislocation. The risk of recurrent dislocation is low following this procedure.     

Recurrent anterior shoulder instability: a review of the Latarjet procedure and its postoperative rehabilitation

The shoulder is the most common joint to dislocate in the human body, with the dislocation often occurring in the anterior direction. This injury frequently results in soft tissue injury (eg, labral tear, capsular stretching) or bone injury (eg, glenoid or humeral head bone loss), which commonly leads to persistent deficits of shoulder function and a high risk of subsequent instability episodes in young, active patients. Patients with a significant degree of glenoid bone loss (> 25%) may require surgical intervention using the Latarjet procedure, which is an open bony augmentation of the glenoid. This procedure involves transferring the tip of the coracoid to the anteroinferior glenoid, creating a bony block and musculotendinous sling to prevent instability. Rehabilitation after the procedure is a slow progression over 4 to 6 months to regain range of motion and strength, while protecting the bony augmentation. Recent reports have shown success with the Latarjet procedure, as indicated by patient satisfaction scores and a low rate of recurrent instability.     

Arthroscopic treatment of synovial chondromatosis that possibly developed after open capsular shift for shoulder instability

Synovial chondromatosis is a rare disease with an unknown etiology, and can be defined as a synovial process characterized by the formation of metaplastic cartilaginous foci inside the connective tissue of articular surfaces. The disease is classified as primary or secondary. The cause of primary disease is unknown, but its pathogenesis involves the development of chondroid foci in synovial membranes. Secondary disease is caused by synovial tissue pathophysiologies, such as, trauma or infection, adjacent to an involved joint. Plain radiographs reveal multiple calcific nodules in glenohumeral joints. However, X-ray diagnosis is often delayed and extremely difficult when the disease is not calcified. Magnetic resonance imaging (MRI) and computed tomography are helpful. For treatment, open or arthroscopic synovectomy and loose body removal are recommended. The authors experienced a rare case of radiologically non-visible synovial chondromatosis, which was viewed as the cause of postoperative residual pain and limitation of motion in a young male with open capsular shift. This case report is presented to emphasize the role of arthroscopy and MRI in the early diagnosis and treatment of synovial chondromatosis.     

The modified Bristow procedure for anterior shoulder instability: 26-year outcomes in Naval Academy midshipmen

BACKGROUND: Many procedures have been proposed for the correction of anterior shoulder instability. Some of these procedures address the problem anatomically, such as the Bankart procedure, and some prevent instability nonanatomically, such as the Bristow-Latarjet procedure. A modified Bristow procedure was the procedure of choice for anterior shoulder instability among midshipmen at the United States Naval Academy from 1975 to 1979. HYPOTHESIS: The modified Bristow procedure for anterior shoulder instability provides good shoulder function and stability in the long term. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: There were 52 shoulders in 49 patients reviewed at a mean follow-up of 26.4 years. The Rowe score, Single Assessment Numeric Evaluation, and Western Ontario Shoulder Instability Index were used to assess outcomes. RESULTS: The mean Rowe score was 81.8 (range, 5-100), and the mean Single Assessment Numeric Evaluation score was 82.9 (range, 30-100), with an overall Single Assessment Numeric Evaluation of 71.2% (37 of 52 shoulders) rated as good and excellent. The mean Western Ontario Shoulder Instability Index was 376 of 2100 (range, 0-1560). Overall, recurrent instability occurred in 8 of 52 shoulders (15.4%), with recurrent dislocation in 5 shoulders (9.6%) and recurrent subluxation in 3 shoulders (5.8%). The mean time to recurrent dislocation was 7.0 years. CONCLUSION: This study represents the longest follow-up in the literature of the modified Bristow procedure. The authors have shown nearly 70% good and excellent results and recurrent instability comparable with other long-term follow-up studies of open instability procedures.     

Open repairs for the treatment of anterior shoulder instability

Successful treatment of anterior instability of the shoulder requires a balance between restoring joint stability and minimizing loss of glenohumeral motion. The choice of treatment should be individualized on the basis of the patient's occupation and level of participation in sports, as well as on the degree of instability of the shoulder. Despite discussions to the contrary, there is no single "essential lesion," as proposed by Bankart, that is responsible for recurrent anterior shoulder instability, although the Bankart lesion is by far the most important. The choice of operative treatment must be tailored to correct the abnormality that is identified at the time of surgery. A variety of promising arthroscopic techniques have been developed for the treatment of anterior shoulder instability; however, open stabilization remains the standard, especially for severe instabilities, revision procedures, and for athletes who participate in contact sports. This article will review the open surgical techniques used for treatment of anterior instability of the shoulder. Both current and historical operations will be discussed. Regardless of which procedure is chosen by a surgeon, the treatment should follow the guidelines taught by Rowe: anatomic dissection at the time of surgery, identification and repair of the lesions responsible for the instability, returning tissues to their anatomic locations, and early postoperative range of motion. By following these guidelines, the results of treatment of anterior instability of the shoulder can be optimized.     

创伤性复发性肩关节前脱位的关节镜检查和手术治疗

目的 利用关节镜观察创伤性复发性肩关节前脱位的病理类型和病变程度,为手术方法的选择提供依据,探讨改良Bristow术式和镜下Bankart重建术的临床疗效. 方法 回顾性研究1997年7月～2007年10月,创伤性复发性肩关节前脱位患者62例,其中男44例,女18例;年龄21～67岁.平均39.8岁.术前脱位痫程平均87个月.手术中先行肩关节镜检查,根据镜下观察关节脱位的病理类型、病变程度如:有无肩盂、肱骨头骨性缺损、Bankart 损伤程度和关节囊盂肱切带松弛等病变分别行政良Bristow手术或关节镜下缝合锚Bankart 重建术.疗效评估用加州大学洛杉矶分校(UCLA)功能评分. 结果 行改良Bristow手术45例,关节镜下缝合锚Bankaa重建术17例.,术后平均随访64.2个月,术前与术后平均UCLA评分分别为22.6±4.4和29.8±4.2(P＜0.01),肩关节前屈上举分别为(136.8±14.2).和(156.6±17.8).(P＜0.01),外展90°位外旋(52,5±16.4)°和(72.4±11.3)°(P＜0.01).终末随访时所有患者均未发生术后再次脱位,术后恐惧试验阳性6例(9.6%),其中60例(97%)患并恢复术前工作.所有患者被问及若健侧肩关节出现相同疾病时.都愿意接受相同手术治疗. 结论 利用关节镜观察创伤性复发性肩关节前脱位的病理改变及病因,为选择适当的手术方法提供参考.清晰处理肩关节不稳定病变原因、重建肩关节解削结构,恢复关节的稳定性,掌握好不同手术方法的指征,无论是改良Bristow手术方法还是镜下缝合锚Bankart 重建术都应是治疗复发性肩关节前脱位的有效方法.     

Long-term evaluation of the Roux-Elmslie-Trillat procedure for patellar instability: a 26-year follow-up

BACKGROUND: Few published articles exist reporting the long-term evaluation of the Roux-Elmslie-Trillat procedure. PURPOSE: To assess the long-term effect of the Roux-Elmslie-Trillat procedure in preventing recurrent subluxation and dislocation of the patella. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Eighteen patients who underwent the Roux-Elmslie-Trillat procedure for dislocation or subluxation of the patella were identified from a group previously evaluated at a mean follow-up of 3 years. The prevalence of recurrent subluxation or dislocation at a mean follow-up of 26 years was compared with the prevalence reported at the mean follow-up of 3 years. Although not the focus of this study, Cox functional scores were obtained from the smaller group and compared with the results at the 3-year follow-up. RESULTS: Seven percent (95% confidence interval, 0.00-0.32) of the patients had recurrent subluxation at 26 years compared with 7% (95% confidence interval, 0.03-0.13) of the study population reported at 3 years (P = 1.00). Fifty-four percent (95% confidence interval, 0.27-0.79) rated their affected knee as good or excellent at 26 years compared with 73% (95% confidence interval, 0.64-0.81) of the larger study population reported at 3 years (P = .14). CONCLUSION: The prevalence of recurrent subluxation and dislocation in patients with patellofemoral malalignment who underwent the Roux-Elmslie-Trillat procedure for dislocation or subluxation of the patella is similar at 3 and 26 years after the procedure. The long-term functional status of the affected knee in patients who underwent the Roux-Elmslie-Trillat procedure declined.     

Anatomical reconstruction versus tenodesis for the treatment of chronic anterolateral instability of the ankle joint: a 2- to 10-year follow-up, multicenter study

The clinical outcome of anatomical reconstruction or tenodesis in the treatment of chronic anterolateral ankle instability was assessed in a retrospective multicenter study. The anatomical reconstruction group (group A) consisted of 106 patients (mean age at operation 24 ± 8.4 years) and the tenodesis group (group B) of 110 patients (mean age at operation 26 ± 11.4 years). Patients were evaluated at a mean follow-up of 5.5 ± 2.8 years in group A and 5.2 ± 2.9 years in group B. The review protocol included patient characteristics, physical examination, two ankle scoring scales to evaluate the functional results, and standard anteroposterior and lateral radiographs to evaluate degenerative changes. Mechanical stability was evaluated using standardized stress radiographs. A larger number of reoperations was performed in group B (P = 0.008). At physical examination, more patients in group B had a smaller range of ankle motion than those in group A (P = 0.009). ¶A larger proportion of patients in group B had medially located osteophytes, as seen on standard radiographs (P = 0.04). On stress radiographic examination, the mean talar tilt (P = 0.001) and mean anterior talar translation (P < 0.001) were seen to be significantly greater in group B than in group A. There were no differences in mean Karlsson score between the groups, but more patients in group A had an excellent result on the Good score (P = 0.011). Unlike anatomical reconstructions, tenodeses do not restore the normal anatomy of the lateral ankle ligaments. This results in restricted range of ankle motion, reduced long-term stability, an increased risk of medially located degenerative changes, a larger number of reoperations, and less satisfactory overall results.     

Stabilizing effect of the transferred conjoined tendon on shoulder stability

The modified Boytchev procedure, i.e., rerouting of the coracoid process with its attached conjoined tendon (short head of biceps and coracobrachialis) deep to the subscapularis and reattachment to its anatomical location, has been advocated for recurrent anterior glenohumeral instability with controversial clinical outcomes. We aimed to investigate the dynamic contribution of the conjoined tendon in situ or transferred to the glenohumeral articulation in stable and unstable shoulders. Eight cadaveric shoulders were tested with the arm in 90° abduction and 90° external rotation. A constant 1.5 kg anterior translation force was applied to the proximal humerus, combined with 0, 1.5, 3.0 kg of load applied to the conjoined tendon sequentially. Anterior displacement of the humeral head relative to the scapula was recorded before and after an imitation Bankart lesion was created, and after treated with the modified Boytchev procedure for the Bankart lesion. Application of load to the conjoined tendon significantly reduced anterior displacement of the humeral head either with the capsule intact or with Bankart lesion simulated. The most significant decrease of the anterior displacement occurred when the conjoined tendon was transferred beneath the subscapularis. Our findings show that the conjoined tendon per se has a stabilizing effect on stable and unstable shoulders and therefore provide scientific support for the treatment of recurrent shoulder instability using the modified Boytchev procedure.     

The value of ultrasonography in the preoperative diagnostic evaluation of patients with recurrent anterior shoulder dislocation: a prospective study of 44 patients

The purpose of this study was to investigate the value of ultrasonography in the pre-operative assessment of patients with recurrent post-traumatic, anterior shoulder instability. Forty-four consecutive patients, 44 men and 12 women, with unilateral, post-traumatic, recurrent instability of the shoulder were included in the study. One experienced radiologist examined all patients, using a 5.0 or 7.5 MHz linear-array transducer, with the arm in different positions, one of which was used to provoke apprehension of the shoulder. Special attention was paid to the evaluation of the joint capsule, the anterior labrum, especially in terms of the presence of a Bankart lesion. All patients were subsequently treated surgically. After a diagnostic arthroscopy either an open or arthroscopic stabilisation of the shoulder was performed. Ultrasonography disclosed an unstable anterior labrum (equivalent to a Bankart lesion) in 36 shoulders; the lesion was verified in all 36 shoulders during arthroscopy. In three shoulders, arthroscopy disclosed an injured labrum, which had healed in an anterio-medial position on the scapular neck. In these three shoulders, ultrasonography failed to show any lesion. In five shoulders no Bankart lesion was found at arthroscopy. All these patients had increased shoulder laxity, and ultrasonography did not show any Bankart lesion. Furthermore a judgement of the joint capsule was not possible either. A bony Bankart lesion was found in four shoulders, using both arthroscopy and ultrasonography. The sensitivity of the ultrasonographic evaluation was 92%, and the specificity 100%. The positive predictive value was 100%, and the negative predictive value 63%. Ultrasonography showed a high correlation with the arthroscopic findings, with a high sensitivity and specificity. Therefore, we conclude that US can give important pre-operative information in patients with recurrent, unilateral, post-traumatic, anterior shoulder instability.     

Arthroscopic versus open shoulder stabilization for recurrent anterior instability: a prospective randomized clinical trial

BACKGROUND: Arthroscopic stabilization for anterior shoulder instability has been reported to result in a higher rate of recurrent instability compared to traditional open techniques. PURPOSE: To test the null hypothesis that there is no difference in the clinical outcomes in patients with recurrent anterior shoulder instability treated with open or arthroscopic stabilization. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: A consecutive series of 64 patients with recurrent anterior shoulder instability were randomized to receive either arthroscopic or open stabilization by a single surgeon. Magnetic resonance arthrogram studies were obtained preoperatively. These findings were compared to arthroscopic findings. Postoperative evaluations included range of motion, stability, and subjective assessments including Single Assessment Numeric Evaluation, Simple Shoulder Test, Western Ontario Instability Index, and University of California, Los Angeles evaluation. Failure was defined as a second dislocation, recurrent subluxation, or symptoms precluding return to previous work or unrestricted active military duty. RESULTS: Sixty-one patients, 29 who received open stabilization and 32 who received arthroscopic stabilization, were evaluated at a mean of 32 months postoperatively (range, 24-48 months). Patient demographics were equivalent. Preoperative magnetic resonance arthrogram findings were confirmed at arthroscopic examination. The mean operative time was significantly shorter for the arthroscopic repairs (59 vs 149 minutes; P < .001). There were 3 clinical failures (2 open stabilizations, 1 arthroscopic stabilization) by the established criteria. There was a statistically significant improvement from preoperative to postoperative Single Assessment Numeric Evaluation scores in both groups (P < .001). The mean loss of motion (compared to the contralateral shoulder) was greater in the open shoulders. Subjective evaluations were equal in both groups. Conclusion: Clinical outcomes after arthroscopic and open stabilization were comparable. Preoperative magnetic resonance arthrograms in shoulders with anterior instability allow an accurate diagnosis of intra-articular abnormality that correlates well with operative findings. Arthroscopic stabilization for recurrent anterior shoulder instability can be performed safely; the clinical outcomes are comparable to those after traditional open stabilization.     

Open Bankart repair with suture anchors for traumatic recurrent anterior shoulder instability: comparison of results between small and large Bankart lesions

This retrospective study was to demonstrate the clinical outcome of open Bankart repair with suture anchors for recurrent anterior shoulder instability, and to compare surgical results of small (<3 clock units) and large (>3 clock units) Bankart lesions. With an average follow-up of 55.6 months (2–8 years), there were 82 patients (60 right, 22 left shoulders) with the mean age of 27 years accepting open Bankart repair with suture anchors and capsular shift procedure by the same team. According to surgical findings, these patients were grouped into small (<3 clock units) and large (>3 clock units) Bankart lesions. Subjective outcomes were recorded according to the Bankart scoring system of Rowe. Rowe scores averaged 85.9±12.9 (range 25–100). The patients, 92–7 %, had objectively excellent or good results. Twenty nine patients (35.4%) had small Bankart lesions and 53 patients had large Bankart lesions. The Rowe scores in small Bankart lesions were better than that in large Bankart lesions (93.5±6.8 vs.81.8±13.6, Wilcoxon rank sum test, P<0.001). Mean scores of stability (Wilcoxon rank sum test, P=0.043), motion (Wilcoxon rank sum test, P=0.037), and function (Wilcoxon rank sum test, P<0.001) in small lesions also had superior outcomes than in large lesions. Four patients (4.9%) got fair results and two (2.4%) patients got poor results at the end of follow-up. The average loss of external rotation is 10°. Open Bankart repair with the aid of suture anchors still got satisfactory results in the treatment of traumatic recurrent anterior instability of the shoulder. The size of the Bankart lesion was a factor affecting surgical outcome. Small Bankart lesions usually got better results than large Bankart lesions.     

Glenohumeral instability: evaluation using MR arthrography of the shoulder

In the setting of glenohumeral instability or when internal derangement of the shoulder joint is suspected, MR arthrography has been demonstrated to be an accurate diagnostic imaging technique. Knowledge of the complex anatomy of the shoulder and its variations is essential in order to maximize diagnostic accuracy. Received: 24 February 1999 Revision requested: 19 April 1999 Revision received: 12 May 1999 Accepted: 13 May 1999     

Return to sports after arthroscopic capsulolabral repair using knotless suture anchors for anterior shoulder instability in soccer players: minimum 5-year follow-up study

Purpose

To report the return to sports and recurrence rates in competitive soccer players after arthroscopic capsulolabral repair using knotless suture anchors at a minimum of 5 years of follow-up.

Methods

All competitive soccer players with anterior glenohumeral instability treated by arthroscopic capsulolabral repair using knotless suture anchors between 2002 and 2009 were retrospectively identified through the medical records. Inclusion criteria were: no previous surgical treatment of the involved shoulder, absence of glenoid or tuberosity fractures, absence of large Hill–Sachs or glenoid bone defect, minimum follow-up of 5 years, instability during soccer practice or games, and failure of non-surgical treatment. The charts of included players were reviewed, and a phone call was performed in a cross-sectional manner to obtain information on: current soccer, return to soccer, recurrence of instability, shoulder function (Rowe score), and disability [Quick-Disability of the Arm, Shoulder, and Hand (DASH) score and Quick-DASH Sports/Performing Arts Module].

Results

Fifty-seven young male soccer players were finally included with a median (range) follow-up of 8 (5–10) years. Forty-nine (86 %) of the soccer players were able to return to soccer and 36 of them (73 %) at the same pre-injury level. There were 6 (10.5 %) re-dislocations in the 57 players, all of them of traumatic origin produced during soccer and other unrelated activities. The main reasons to not return to soccer were: knee injuries (two players), changes in personal life (two players), and job-related (three players). None of the players quit playing soccer because of their shoulder instability injury. The median (range) Rowe score, Quick-DASH score, and Quick-DASH sports score were 80 (25–100), 2.3 (0–12.5), and 0 (0–18.8), respectively.

Conclusions

Competitive soccer players undergoing arthroscopic capsulolabral repair with knotless suture anchors for shoulder instability without significant bone loss demonstrate excellent return to play at mid-to-long-term follow-up, with a 10.5 % chances of re-dislocating.

Level of evidence

IV.