ABSTRACT:
OBJECTIVE To clinically evaluate the results of patients undergoing arthroscopic surgical treatment
of anterior shoulder instability.
METHODS A retrospective study of 94 patients. With a minimum follow-up of 24 months, we sought
to correlate the characteristics of the patients and the surgery, such as age, gender,
type of injury (traumatic or atraumatic) and the patient's position during surgery
(lateral decubitus and beach chair) with the results obtained, the recurrence rate,
the lateral rotation loss, the residual pain, and the functional scores of Carter-Rowe,
University of California at Los Angeles (UCLA), and Constant-Murley.
RESULTS We observed a recurrent dislocation rate of 11.7%, lateral rotation loss in 37.23%
of the patients, and some degree of residual pain in 51.6% of them. We obtained a
mean Carter Rowe score of 85.37, representing 86% of good/excellent results. In the
UCLA score, we obtained 88% of good/excellent results, similar to those obtained in
the Constant-Murley score (86%).
CONCLUSION The arthroscopic treatment of the anterior instability of the shoulder presents satisfactory
results and low index of important complications, being the method of choice for most
patients.
Keywords: arthroscopy; articular instability; shoulder; retrospective studies.
RESUMO:
OBJETIVO Avaliar clinicamente os resultados de pacientes submetidos a tratamento cirúrgico
artroscópico de instabilidade anterior do ombro.
MÉTODOS Estudo retrospectivo de 94 pacientes. Com seguimento mínimo de 24 meses, buscamos
correlacionar as características dos pacientes e da cirurgia, como idade, gênero,
tipo de lesão (traumática ou atraumática) e posição do paciente na cirurgia (decúbito
lateral e cadeira de praia) com os resultados obtidos, avaliando o índice de recidivas
de luxação, a perda de rotação lateral, a dor residual, e os escores funcionais de
Carter-Rowe, da University of California at Los Angeles (UCLA) e de Constant-Murley.
RESULTADOS Observamos uma taxa de recidiva de luxação de 11,7%, perda de rotação lateral em 37,23%
dos pacientes, e algum grau de dor residual em 51,6%. Obtivemos uma pontuação média
no escore de Carter Rowe de 85,37, representando 86% de resultados bons/excelentes.
No escore da UCLA, obtivemos 88% de resultados bons/excelentes, índice semelhante
aos encontrados no escore de Constant-Murley (86%).
CONCLUSÃO O tratamento artroscópico da instabilidade anterior do ombro apresenta resultados
satisfatórios e baixo índice de complicações importantes, podendo ser o método de
escolha para a maioria dos pacientes.
Palavras-chave: artroscopia; instabilidade articular; ombro; estudos retrospectivos.
FIGURES
| Citation: Storti TM, Lima RA, Costa EBeS, Simionatto JE, Simionatto C, Paniago AF. Postoperative Evaluation of Patients Submitted to Arthroscopic Repair of Anterior Shoulder Instability. 55(3):339. doi:10.1055/s-0039-3402467 |
| Conflict of Interests The authors declare that have no conflict of interests. |
| Received: April 04 2018; Accepted: February 05 2019 |
INTRODUCTION
Anterior glenohumeral dislocation is the most common kind of shoulder dislocation. It results from damage to the capsulolabral complex in the anteroinferior portion of the glenoid, and is also referred to as Bankart lesion or essential lesion.1-4
Surgical repair, either open or arthroscopic, is indicated for recurrent dislocations. Among the surgical treatments for shoulder stabilization, arthroscopic repair has become increasingly popular due to reduced movement loss, milder surgical aggression, subscapularis preservation and low morbidity compared to open surgery.5
Several patient-related factors contributing to the recurrence risk following the Bankart arthroscopic repair have been reported, including younger age at surgery, male gender, bilateral instability, ligamentous hyperlaxity, participation in collision sports, and early return to contact sports.6 Injury-associated risk factors, such as erosion or glenoid deficiency, Hill-Sachs lesion size, and anterior glenoid border involvement were also implicated.7 Accurate identification of the risk factors associated with Bankart arthroscopic repair failure and capsular dislocation helps the surgeon stratify the risk for an individual patient, enabling proper counseling.
Therefore, the present study aims to perform a functional assessment and to analyze the factors influencing the outcome of patients with anterior shoulder instability submitted to the arthroscopic treatment of anterior shoulder instability.
MATERIALS AND METHODS
From March to May 2017, 94 patients were retrospectively analyzed through a review of medical records and subsequent clinical evaluation. All patients underwent arthroscopic surgical treatment for anterior shoulder instability in two private hospitals and by four independent surgeons between January 2010 and December 2014. Ten patients operated on during this period were excluded due to non-attendance at the follow-up.
The medical records had the following information: patient identification, clinical history characterizing the cause of the instability (traumatic or atraumatic), functional limitation, preoperative physical examination, preoperative imaging, and surgical description. The postoperative follow-up time ranged from 24 to 72 months, with a mean period of 40 months, to assess the functional limitation, decreased lateral rotation, instability, pain, the and functional scores of Carter-Rowe, University of California at Los Angeles (UCLA) and Constant-Murley through clinical and physical examinations performed by an external physician.
The present study included patients with recurrent anterior shoulder instability (dislocation or subluxation) and Bankart lesion, all operated arthroscopically and with a minimum postoperative follow-up time of 24 months. The exclusion criteria were traumatic dislocation associated with neurovascular injury, fracture on other sites of the shoulder girdle, glenoid bone loss greater than 25%, Hill-Sachs fracture involving more than 1/4 of the humeral head, previous surgeries at the involved shoulder, and multidirectional instability.
Two surgeons performed the procedures with the patients in lateral position. The surgical procedure was performed under general anesthesia and brachial plexus block. The limb was kept at approximately 70º of abduction and 20º of flexion, and fixed and vertical longitudinal traction with 4- to 7-kg weights was applied.
The other two surgeons performed the procedures with the patients in the beach chair position, that is, with a trunk elevation of at least 70º, around 30º of knee flexion, and gentle lateral inclination opposite to the operated side.
The surgeons used conventional arthroscopic portals (posterior, anterosuperior and anteroinferior). During the procedure, the joint was inspected to assess the presence of associated lesions. Subsequently, the anteriorinferior labral lesion and its extension were observed, followed by capsulolabral release and glenoid border scarification; next, the labral lesion was fixed with two to four bioabsorbable anchors.
Postoperatively, the patients remained with continuous immobilization on a Velpeau sling for three weeks. Pendular motion and passive self-motion were then initiated over the following two weeks; lateral rotation movements beyond 20º were allowed from the 6th week onwards. Muscle strengthening was dependent on the range of motion of the operated shoulder, and usually began in the third postoperative month. Return to contact or collision sports activities was allowed from the sixth month onwards.
In the descriptive analysis, the observed data were presented as tables; the continuous and quantitative variables were expressed as medians and interquartile ranges (IQRs), whereas the categorical and qualitative variables were expressed as frequencies (n) and percentages (%).
The inferential analysis employed the following methods:
- the association of the Carter-Rowe, UCLA and Constant-Murley scores with the clinical variables (age, gender, type of injury and surgical position) was assessed by the Mann-Whitney test for categorical data and the Spearman correlation coefficient for numerical data; and
- the association of dislocation recurrence, residual pain, loss of lateral rotation and apprehension with the clinical variables was analyzed by the Chi-squared (χ2) or Fisher exact test for categorical data and by the Mann-Whitney test for numerical data.
A nonparametric method was applied because the variables under study did not present normal (Gaussian) distribution due to the rejection of the normality hypothesis by the Shapiro-Wilks test. The significance was determined as a 5% level. The statistical analysis was performed using Statistical Analysis System (SAS, SAS Institute, Inc., Cary, North Carolina, US) software, version 6.11.
All patients signed the Informed Consent Form. The present study was approved by the Committee of Ethics in Research with Human Beings under Opinion no. 2,197,472, CAAE 70807917.6.0000.0023.
RESULTS
In total, 94 patients were evaluated in the present study, with a follow-up period of 2 to 6 years after surgery; 74 subjects (78,7%) were male, and 20 (21,3%) were female, with ages at the surgical procedure ranging from 17 to 62 years (Table 1). A total of 11 (11.7%) patients presented dislocation recurrence, 35 (37.23%) had decreased lateral rotation, 48 (51.06%) reported some degree of residual pain, and 23 (24.46%) were positive at the apprehension test (Table 2).
| Variable | N | % |
|---|---|---|
| Gender | ||
| Male | 74 | 78.7 |
| Female | 20 | 21.3 |
| Age at surgery (years) | ||
| Median value (Q1-Q3) | 34 (28-43) | |
| Injury type | ||
| Traumatic injury | 85 | 90.4 |
| Atraumatic injury | 9 | 9.6 |
| Position | ||
| Beach chair | 23 | 24.5 |
| Lateral recumbency | 71 | 75.5 |
| Carter-Rowe score (points) | ||
| Median value (Q1-Q3) | 95 (80-100) | |
| University of California at Los Angeles (UCLA) score (points) | ||
| Median value (Q1-Q3) | 33 (31-35) | |
| Constant-Murley score (points) | ||
| Median value (Q1-Q3) | 95 (87-100) | |
| Redislocation | N | % |
|---|---|---|
| Yes | 11 | 11.7 |
| No | 83 | 88.3 |
| Residual pain | ||
| Yes | 48 | 51.1 |
| No | 46 | 48.9 |
| External rotation loss | ||
| Yes | 35 | 37.2 |
| No | 59 | 62.8 |
| Apprehension | ||
| Yes | 23 | 24.5 |
| No | 71 | 75.5 |
Traumatic instability was prevalent, representing 90.4% of cases (85 patients). The most common surgical positioning was that of lateral decubitus, with 71 of the operated patients (75.5%) of patients underwent surgery in this position. At the clinical evaluation, the median Carter-Rowe score was of 95 (Table 3), with 67 excellent outcomes (71,3%), 14 good outcomes (14,9%), 2 regular outcomes (2,1%) and 11 bad outcomes (11,7%) (Figure 1). Bad outcomes were associated with dislocation recurrence, and they occurred in 9 male patients (81,8%) and in 2 female patients (18,2%). Although more prevalent in male patients, our study found no statistically significant difference between gender and dislocation recurrence. Similarly, there was no significant correlation between the Carter-Rowe score and age at the time of surgery (rs = 0.162; p = 0.011).
| Variable | n | Median value | Interquartile range | Minimum | Maximum | ||
|---|---|---|---|---|---|---|---|
| Age at surgery (years) | 94 | 34 | 27.8 | - | 43 | 17 | 62 |
| Score (points) | |||||||
| Carter-Rowe | 94 | 95 | 80 | - | 100 | 15 | 100 |
| University of California at Los Angeles (UCLA) | 94 | 33 | 31 | - | 35 | 23 | 35 |
| Constant-Murley | 94 | 95 | 87 | - | 100 | 68 | 100 |
In the UCLA score evaluation, there were 83 patients (88,3%) with good/excellent outcomes and 11 patients (11,7%) with bad/regular outcomes (Figure 2). There was a significant direct correlation between the UCLA score and the patient's age at the time of surgery (rs = 0.250; p = 0.015). Therefore, the older the age, the higher the expected score.
In the Constant-Murley score evaluation, there were 65 patients (69,2%) with excellent outcomes, 18 (19,1%) good outcomes, 10 (10,7%) regular outcomes and 1 poor outcome (1%) (Figure 3). None of the three scores presented a statistically significant correlation with gender, type of injury or surgical position.
In addition, there was no statistically significant correlation between the clinical variables (gender, age, type of injury and surgical position) and dislocation recurrence, residual pain, loss of lateral rotation and apprehension (Tables 4, 5, 6, 7). The subgroup with residual pain, however, was significantly younger than the subgroup without residual pain (p = 0.016).
| Variable | With redislocation | Without redislocation | p-value | ||
|---|---|---|---|---|---|
| Gender | |||||
| Male | 9 | 81.8 | 65 | 78.3 | 0.57 |
| Female | 2 | 18.2 | 18 | 21.7 | |
| Age at surgery (years) | |||||
| Median value (Q1-Q3) | 32 (23-38) | 34 (28-43) | 0.10 | ||
| Injury type | |||||
| Traumatic injury | 11 | 100 | 74 | 89.2 | 0.31 |
| Atraumatic injury | 0 | 0 | 9 | 10.8 | |
| Surgical position | |||||
| Beach chair | 4 | 36.4 | 19 | 22.9 | 0.26 |
| Lateral recumbency | 7 | 63.6 | 64 | 77.1 | |
Note: The categorical data were expressed as frequencies and percentages, and they were compared using the Chi-squared test or the Fisher exact test; age was expressed as medians and interquartile ranges and was compared using the Mann-Whitney test.
| Variable | With residual pain | Without residual pain | p-value | ||
|---|---|---|---|---|---|
| Gender | |||||
| Male | 41 | 85.4 | 33 | 71.7 | 0.085 |
| Female | 7 | 14.6 | 13 | 28.3 | |
| Age at surgery (years) | |||||
| Median value (Q1-Q3) | 32 (25-38) | 37 (30-44) | 0.016 | ||
| Injury type | |||||
| Traumatic injury | 43 | 89.6 | 42 | 91.3 | 0.52 |
| Atraumatic injury | 5 | 10.4 | 4 | 8.7 | |
| Surgical position | |||||
| Beach chair | 12 | 25.0 | 11 | 23.9 | 0.9 |
| Lateral recumbency | 36 | 75.0 | 35 | 76.1 | |
| Variable | With external rotation loss | Without external rotation loss | p-value | ||
|---|---|---|---|---|---|
| Gender | |||||
| Male | 29 | 82.9 | 45 | 76.3 | 0.45 |
| Female | 6 | 17.1 | 14 | 23.7 | |
| Age at surgery (years) | |||||
| Median value (Q1-Q3) | 35 (25-44) | 34 (28-40) | 0.53 | ||
| Injury type | |||||
| Traumatic injury | 30 | 85.7 | 55 | 93.2 | 0.20 |
| Atraumatic injury | 5 | 14.3 | 4 | 6.8 | |
| Surgical position | |||||
| Beach chair | 6 | 17.1 | 17 | 28.8 | 0.20 |
| Lateral recumbency | 29 | 82.9 | 42 | 71.2 | |
| Variable | With apprehension | Without apprehension | p-value | ||
|---|---|---|---|---|---|
| Gender | |||||
| Male | 19 | 82.6 | 55 | 77.5 | 0.42 |
| Female | 4 | 17.4 | 16 | 22.5 | |
| Age at surgery (years) | |||||
| Median value (Q1-Q3) | 31 (25-40) | 34 (28-43) | 0.29 | ||
| Injury type | |||||
| Traumatic injury | 23 | 100 | 62 | 87.3 | 0.070 |
| Atraumatic injury | 0 | 0 | 9 | 12.7 | |
| Surgical position | |||||
| Beach chair | 5 | 21.7 | 18 | 25.4 | 0.72 |
| Lateral recumbency | 18 | 78.3 | 53 | 74.6 | |
DISCUSSION
The surgical treatment for anterior shoulder instability must be chosen based on factors such as age, previous dislocations, occupation, level of physical activity, ligament laxity, overall health status of the patient, degree of humeral head and glenoid bone involvement, and the presence of associated conditions, such as upper labral (superior labral tear from anterior to posterior, SLAP) injuries and rotator cuff tendon rupture.8 Choosing the most appropriate treatment for each patient can influence the outcomes and minimize the risk of complications.
The best method for labral lesion repair is still debatable.9 The anatomical procedures include open and arthroscopic Bankart surgeries, which aim to restore the original shoulder anatomy and involve labral lesion repair.10 Bankart open surgery, which is performed with labrum mobilization and fixation, is still considered the gold standard for anterior instability treatment.11 However, conditions such as incision size, risk of subscapularis muscle weakness, loss of shoulder range of motion (especially lateral rotation) and difficulty in accessing other intra-articular injuries have favored the choice for the arthroscopic procedure. Other advantages of arthroscopy are reduced blood loss, shorter surgery duration and greater esthetic satisfaction.12
The dislocation recurrence rates after arthroscopic surgery have been decreasing due to technological advances and a better understanding of previous errors. In 2007, Balg and Boileau13 described a 14.5% recurrence rate after Bankart arthroscopic surgery. Castagna et al.14 obtained a 23% recurrence rate in a 10-year follow-up of 43 patients submitted to arthroscopy. In a meta-analysis, Petrera et al15 compared the open Bankart and arthroscopic surgeries and found a dislocation recurrence rate 6.3% lower in the arthroscopy group.
Ahmed et al6 also reported better results with arthroscopic techniques, with a dislocation recurrence rate of 13.2% in a total of 302 patients. In our study, all recurrence cases were associated with traumatic instability, with an 11.7% rate.
As for loss of lateral rotation, Bottoni et al16 demonstrated that the decrease in range of motion was of 2 o to 3o in the arthroscopic group, and of 6.5o in the open surgery group. In our study, loss of lateral rotation was observed mostly in patients with traumatic instability, which is similar to the results reported by Ferreira Neto et al,17 who also found a greater lateral rotation limitation in patients with such a feature. These results may be justified by the better capsular ligament accommodation in patients with atraumatic injuries when compared to patients with traumatic instability.17-19 Almeida Filho et a.,20 after performing postoperative clinical and radiographic evaluations of 49 patients, observed that despite the arthrosis-related lateral rotation decrease, it was not possible to ascertain a cause-effect relationship between them.
Residual pain is a common postoperative complaint in patients surgically treated for anterior shoulder instability. Several authors21-23 attribute this complication to injuries associated with instability and that may not be diagnosed at first, especially partial rotator cuff tears, SLAP injuries, and joint degenerative changes. In our study, approximately 51% of the patients had some degree of postoperative residual pain, and there was an inverse association between age and pain. The younger the age at surgery, the greater the occurrence of postoperative pain, which may be justified by the higher level of activity of this group of patients. In addition, as noted by Almeida Filho et al,20 there is a significant relationship between postoperative glenohumeral arthrosis development and younger age at the time of surgery and first dislocation, corroborating our observation.
Some studies13,24-27 have shown that younger patients are at an increased risk of recurrence after arthroscopic surgical stabilization, but no age has been defined. According to Ahmed et al,6 age alone is not sufficient to determine the treatment offered to younger patients, but it is clearly an important factor to predict the risk of recurrence. In our series, there was no statistically significant correlation between age and dislocation recurrence; the median age of patients with and without recurrence was similar (32 versus 34 years old).
Three functional scores, the UCLA, Carter-Rowe and Constant-Murley scores, were used for outcome evaluation. The median Carter-Rowe score was 95, with 67 excellent outcomes, 14 good outcomes, 2 regular outcomes and 11 poor outcomes. As for the UCLA score, there were 83 patients with good/excellent outcomes and 11 patients with bad/regular outcomes. Using the Constant score, 65 patients presented excellent outcomes, 18 had good outcomes, 10 had regular outcomes, and 1 had a poor outcome. Regarding the three scores, all patients with regular/poor outcomes were those with dislocation recurrence.
The results reported by Boileau et al28 in 91 patients showed a mean Carter-Rowe score of 77.8 points (ranging from 15 to 100 points). Balg and Boileau13 observed an average Carter-Rowe score of 81.5 points (range: 10-100 points) after evaluating 131 operated patients. Neri et al,29 analyzing 11 patients, found a Carter-Rowe score of 74.5 points (range: 35-100 points), and an average UCLA score of 29.6 points (ranging from 24 to 35 points), with good/excellent outcomes in 8 patients (72.7%) and regular/poor outcomes in 3 subjects (27.3%). In a study evaluating 314 shoulders from 302 patients, Godinho et al30 demonstrated an average Carter-Rowe score of 91.8, ranging from 25 to 100 points, and an UCLA score of 33.8 points, with 97.6% of good/excellent outcomes. Our series presented a significant direct correlation between the UCLA score and age (rs = 0.250; p = 0.015), indicating that, the older the age, the higher the expected UCLA score.
Regardless of the method used, the main postoperative complication is dislocation recurrence, which is associated with the previously mentioned risk factors. Thus, the use of scores such as the Instability and Severity Index Score (ISIS) may indicate the technique that provides the greatest benefits for patients. The score includes age at time of surgery, degree of sports participation, type of sport practiced, ligamentous laxity, presence of Hill-Sachs lesion, and loss of glenoid contour to generate a total of 10 points. According to Balg and Boileau,13 patients with scores of up to six points benefit most from the arthroscopic technique, while lower scores are indications for open surgeries, especially the Latarjet procedure.
The main limitations of the study include its retrospective nature, which did not enable a rigorous preoperative functional assessment, the short follow-up period, and the non-normal data distribution, requiring the use of nonparametric tests.
CONCLUSIONS
We conclude that the arthroscopic repair of anterior shoulder instability has satisfactory outcomes in the functional scores at the short/medium-term, with a low rate of severe, limiting complications, and it can be a method of choice for most patients. Bad/regular outcomes were associated with dislocation recurrence. Postoperative pain was associated with younger age at surgery, whereas lateral rotation limitation was related to the type of instability (traumatic injury).
REFERENCES
