Glenohumeral volume reduction in arthroscopic shoulder reconstruction: a cadaveric analysis of suture plication and thermal capsulorrhaphy

Computed Tomography Scan Versus Saline Load Test for Detection of Traumatic Shoulder Arthrotomy: A Cadaveric Study

OBJECTIVES

Traumatic shoulder arthrotomy (TSA) is a rare injury that is commonly detected through saline load test (SLT). There are no studies that have studied the ability of computed tomography (CT) scan to detect a TSA. The purpose of this study is to determine the ability of CT scan to detect a TSA and compare it with the SLT.

METHODS

Twelve cadaveric shoulders were included in the study. Before intervention, a CT scan was conducted to determine presence of intra-articular air. After confirmation that no air was present, an arthrotomy was made at the anterior or posterior portal site. A CT was obtained postarthrotomy to evaluate for intra-articular air. Each shoulder then underwent an SLT to assess the sensitivity of SLT and the volume needed for extravasation.

RESULTS

Twelve shoulders were included after a pre-intervention CT scan. Six shoulders received an arthrotomy through the anterior portal and six shoulders received an arthrotomy through the posterior portal. After the arthrotomy, air was visualized on CT scan in 11 of the 12 shoulders (92%). All 12 shoulders demonstrated extravasation during SLT. The mean volume of saline needed for extravasation was 29 mL with an SD of 10 and range of 18-50 mL.

CONCLUSIONS

CT scan is a sensitive modality (sensitivity of 92%) for detection of TSA. In comparison, SLT is more sensitive (sensitivity of 100%) and outperforms CT scan for the diagnosis of TSA in a cadaveric model. Further research is needed to solidify the role that CT imaging has in the diagnosis of TSAs.

Multidirectional instability of the shoulder: surgical techniques and clinical outcome

Multidirectional instability of the shoulder has a complex pathoanatomy. It is characterized by a redundant glenohumeral capsule and increased joint volume. Subtle clinical presentation, unclear trauma history and multifactorial etiology poseses a great challenge for orthopedic surgeons in terms of diagnosis. Generally accepted therapeutic approach is conservative and the majority of patients achieve good results with rehabilitation. In patients who are symptomatic despite appropriate rehabilitation, surgical intervention may be considered. Good results have been obtained with open inferior capsular surgery, which has historically been performed in these patients. In recent years, advanced arthroscopic techniques have taken place in this field, and similar results compared to open surgery have been obtained with the less-invasive arthroscopic capsular plication procedure.

Management of shoulder instability in hypermobility-type Ehlers-Danlos syndrome

Shoulder instability in hypermobile Ehlers-Danlos syndrome can result in lifelong pain and functional disability. Treatment in this population is complicated by the severe degree of instability as well as the underlying abnormalities of the joint connective tissue. Appropriate care for these patients requires a thorough understanding of the natural history of their disease, knowledge of the available treatment options, and certain special considerations. This article reviews the pathoanatomy, recognition, and management of shoulder instability in the patient with hypermobile Ehlers-Danlos syndrome.

Arthroscopic Bankart repair with an individualized capsular shift restores physiological capsular volume in patients with anterior shoulder instability

PURPOSE

Capsular volume reduction in the context of anterior arthroscopic shoulder stabilization represents an important but uncontrolled parameter. The aim of this study was to analyse capsular volume reduction by arthroscopic Bankart repair with an individualized capsular shift in patients with and without ligamentous hyperlaxity compared to a control group.

METHODS

In the context of a prospective controlled study, intraoperative capsular volume measurements were performed in 32 patients with anterior shoulder instability before and after arthroscopic Bankart repair with an individualized capsular shift. The results were compared to those of a control group of 50 patients without instability. Physiological shoulder joint volumes were calculated and correlated with biometric parameters (sex, age, height, weight and BMI).

RESULTS

Patients with anterior shoulder instability showed a mean preinterventional capsular volume of 35.6 ± 10.6 mL, which was found to be significantly reduced to 19.3 ± 5.4 mL following arthroscopic Bankart repair with an individualized capsular shift (relative capsular volume reduction: 45.9 ± 21.9%; P < 0.01). Pre-interventional volumes were significantly greater in hyperlax than in non-hyperlax patients, while post-interventional volumes did not differ significantly. The average shoulder joint volume of the control group was 21.1 ± 7.0 mL, which was significantly correlated with sex, height and weight (P < 0.01). Postinterventional capsular volumes did not significantly differ from those of the controls (n.s.).

CONCLUSION

Arthroscopic Bankart repair with an individualized capsular shift enabled the restoration of physiological capsular volume conditions in hyperlax and non-hyperlax patients with anterior shoulder instability. Current findings allow for individual adjustment and intraoperative control of capsular volume reduction to avoid over- or under correction of the shoulder joint volume. Future clinical studies should evaluate, whether individualized approaches to arthroscopic shoulder stabilization are associated with superior clinical outcome.

Traumatic Arthrotomy

Evaluation of periarticular traumatic wounds for joint penetration is a common clinical concern for orthopaedic surgeons. Wounds that violate the joint capsule can result in deep infection and sepsis. Understanding the anatomic landmarks and capsular extensions of the major joints is key to proper evaluation. Initial evaluation of periarticular wounds includes thorough examination of the wound and plain radiographs. Historically, the saline load test has been the diagnostic test of choice for assessing traumatic arthrotomy; however, CT has recently been shown to have excellent sensitivity and specificity for detecting open knee joint injuries. Current treatment of traumatic arthrotomy includes intravenous antibiotics and surgical irrigation and débridement. Future areas of research must focus on further validation of CT evaluation and its use in other major joints, standardizing antibiotic treatment, and further delineating the role of nonsurgical management in minor injuries.

The results of Bankart repair without capsular plication in patients with recurrent traumatic anterior shoulder dislocation

PURPOSE

The aim of this study was to evaluate the results of patients with recurrent anterior shoulder dislocation, who had been treated with repair of the Bankart lesion without capsuler plication.

MATERIAL AND METHOD

The study included 22 shoulders of 22 patients (16 males and 6 females) with a mean age of 28 years, who underwent Bankart repair between 2011 and 2014. Patients with bilateral shoulder instability, multiple instability, >25% glenoid bone loss, and those with a history of shoulder surgery were not included in the study. The average follow-up time was 21.2 months. Evaluation was made of the preoperative number of dislocations, postoperative recurrence, functional status, and daily activity performance of the patients. Shoulder range of motion was measured. The results were evaluated using the Rowe shoulder score and the Oxford shoulder instability score.

RESULTS

Recurrence was observed in only one patient who had a shoulder dislocation after trauma, thus giving a recurrence rate of 4.5%. Shoulder range of motion was full in all except that one patient. The mean Rowe shoulder score was 95.5 (excellent) and Oxford shoulder stability score was 44.6 (excellent).

CONCLUSION

No recurrent shoulder dislocation was observed in patients who underwent Bankart repair surgery. Plication was not performed with the Bankart repair. Close to full range of motion was obtained in all patients. In conclusion, Bankart repair alone can be considered to be sufficient for the treatment of traumatic recurrent anterior shoulder instability.

Effect of arthroscopic techniques on joint volume in shoulder instability: Bankart repair versus capsular shift

PURPOSE

The evaluation of glenohumeral joint volume in both unstable (with/without laxity) and stable shoulders (subacromial impingement) and volume reduction potential of arthroscopic techniques: (labral anchor repair vs. capsular shift).

METHODS

Material was based on 133 patients: anterior shoulder instability without laxity (group I, n = 49), with laxity (group II, n = 22) and subacromial impingement (control group, n = 62) operated in 2010-2011. Group I received arthroscopic Bankart repair, group; II - arthroscopic anterior capsular plication, control group - subacromial decompression. Joint volume was measured by fluid aspiration into the syringe via arthroscope, before and after procedure. Then volume reduction potential was calculated.

RESULTS

The following average values of initial joint volume were recorded: group I - 26.8 ml group II - 43.7 ml and the control group - 25.6 ml with significant differences: impingement vs. instability + laxity (p < 0.00001), impingement vs. instability without laxity (p = 0.0001). There was no significant difference between groups I and II. Joint volume was significantly reduced after labral repair (by average of 37 %, 13.8 ml, p < 0.0001). Capsular shift led to an even greater and more significant volume decrease (61 %, 26.7 ml, p < 0.001). Joint volume in the control group was reduced only by 11 %, 3.8 ml (p = 0.046).

CONCLUSIONS

Patients with unstable shoulders have enlarged joint volume as compared to patients with subacromial impingement. Arthroscopic techniques lead to a significant joint volume reduction, with the most powerful effect for capsular shift. Level of Evidence - Level 2.

Open inferior capsular shift for multidirectional shoulder instability in adolescents with generalized ligamentous hyperlaxity or Ehlers-Danlos syndrome

BACKGROUND

The objective of this study was to assess the outcome of open inferior capsular shift for multidirectional shoulder instability in patients with generalized ligamentous hyperlaxity or Ehlers-Danlos syndrome.

METHODS

Data were obtained for 18 open inferior capsular shift surgeries in 15 adolescent patients with generalized ligamentous hyperlaxity or Ehlers-Danlos syndrome with a mean follow-up of 7.5 years. End points were subjective clinical outcome (pain, stability, satisfaction, return to sport), objective clinical outcome (recurrence, complications), and functional outcome scores (American Shoulder and Elbow Surgeons, 11-item version of the Disabilities of Arm, Shoulder and Hand).

RESULTS

Thirteen patients (87%) reported improved pain and stability and were satisfied with the procedure. Nine patients (64%) were able to return to sports. One patient (7%) was dissatisfied with continuous pain and recurrent instability and considered a surgical failure. Seven patients (47%) reported no further episodes of instability. The mean American Shoulder and Elbow Surgeons score at a mean of 7.5 years of follow-up was 88 ± 10 points, and the mean score for the 11-item version of the Disabilities of Arm, Shoulder and Hand was 14 ± 14 points.

DISCUSSION

The management of multidirectional shoulder instability in adolescent patients with generalized ligamentous hyperlaxity or Ehlers-Danlos syndrome is challenging. Open inferior capsular shift results in improvement in subjective and objective shoulder function and stability in adolescent patients with ligamentous hyperlaxity or Ehlers-Danlos who have failed nonoperative treatment. We found no effect of the recalled number of prior dislocations, laterality, and type of hyperlaxity on subjective and objective clinical outcomes.

LEVEL OF EVIDENCE

Level IV; Case Series; Treatment Study.

Factors affecting capsular volume changes and association with outcomes after Bankart repair and capsular shift

BACKGROUND

Capsular laxity is a main contributing factor in recurrent shoulder instability and is suggested to be correlated with increased capsular volume. Arthroscopic capsular shift combined with Bankart repair can reduce the capsular volume and reinforce the redundant capsule; however, as the capsuloligamentous structure has viscoelastic properties, it is possible for the shifted and tensioned capsule of the glenohumeral joint to slowly stretch out again over time, resulting in an increase in capsular volume.

PURPOSE

To analyze changes in capsular volume of the glenohumeral joint over time after arthroscopic Bankart repair and capsular shift, the factors associated with these changes, and their relevance to outcomes.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Included in this study were 105 patients (mean age, 25.8 ± 8.2 years) who underwent arthroscopic Bankart repair and capsular shift for anterior shoulder instability and computed tomography arthrography (CTA) at 3 months and 1 year postoperatively and whose various functional outcomes were evaluated preoperatively and at the last follow-up (>12 months). Among these patients, 27 also had preoperative CTA. These 27 patients were used to make comparisons between preoperative and 3-month postoperative CTA measurements, and all 105 patients were used for all other comparisons. Two raters measured the separate anterior and posterior capsular volume and cross-sectional area at the 5-o'clock position using 3-dimensional (3D) Slicer software. These measurements were subsequently adjusted for each glenoid size. The changes in capsular volume and cross-sectional area at the 5-o'clock position over time, the factors related to higher change in anterior capsular volume, and their correlation with outcomes were evaluated.

RESULTS

Three months postoperatively, the total and anterior capsular volume and anterior cross-sectional area significantly decreased; however, these values increased again at 1 year postoperatively (all P < .01). The inter- and intraobserver reliabilities of the measurements were excellent (interclass correlation coefficient = 0.717-0.945). Female sex, being an elite athlete, and more dislocations before surgery were related to a higher increase in anterior capsular volume at 1 year (all P < .05). Eight patients had redislocation, and 18 exhibited positive apprehension test postoperatively, and these patients showed significantly higher increases in anterior and total capsular volume at 1 year than did those without redislocation or positive apprehension sign (all P < .01). However, with the exception of Rowe score, a higher increase in anterior capsular volume was not related to functional outcome measures.

CONCLUSION

Surgeons should be aware of the re-increase in anterior capsular volume or restretching trait of the anterior capsule over time, even after successful arthroscopic Bankart repair and capsular shift. In this study, women, elite athletes, and those with frequent dislocations were at high risk of capsular restretching. An increase in capsular volume was related to redislocation and positive apprehension sign as well as with Rowe score.

Multidirectional instability of the shoulder: biomechanics, clinical presentation, and treatment strategies

Multidirectional instability (MDI) of the shoulder is a condition where the dislocation occurs in more than one direction with minimal or no causative trauma. Its pathoanatomy is complex and characterized by a redundant capsule, resulting in increased glenohumeral joint volume. The fact that several further factors may contribute to symptom onset complicates the diagnosis and hampers the identification of a therapeutic approach suitable for all cases. There is general agreement that the initial treatment should be conservative and that surgery should be reserved for patients who have not responded to an ad hoc rehabilitation program. We review the biomechanics, clinical presentation, and treatment strategies of shoulder MDI.

Electrothermal arthroscopic capsulorrhaphy: old technology, new evidence. A multicenter randomized clinical trial

BACKGROUND

Radiofrequency technology for shoulder instability was rapidly adopted despite limited clinical evidence and a poor understanding of its indications. Reports of serious adverse events followed, leading to its abandonment. This paper presents findings from a multicenter randomized clinical trial evaluating the safety and efficacy of electrothermal arthroscopic capsulorrhaphy (ETAC) compared with open inferior capsular shift (ICS) and reviews the role of randomized trials in adopting new technology.

METHODS

Patients (>14 years) diagnosed with multidirectional instability or multidirectional laxity with anteroinferior instability and failed nonoperative treatment were enrolled. Patients with bone lesions or labral, biceps anchor, or full-thickness rotator cuff tears were excluded intraoperatively. Outcomes included Western Ontario Shoulder Instability Index, function and recurrent instability at 2 years postoperatively, and surgical times.

RESULTS

Fifty-four subjects (mean age, 23 years; 37 women) were randomized to ETAC (n = 28) or open ICS (n = 26). The groups were comparable at baseline, except for external rotation at the side. At 2 years postoperatively, there were no statistically or clinically significant differences between groups for the Western Ontario Shoulder Instability Index (P = .71), American Shoulder and Elbow Surgeons score (P = .43), Constant score (P = .43), and active range of motion. Recurrent instability was not statistically different (ETAC, 2; open, 4; P = .41). ETAC (23 minutes) was significantly shorter than open ICS (59 minutes) (P < .01) surgery. Three subjects (1 ETAC, 2 open) had stiff shoulders.

CONCLUSIONS

At 2 years postoperatively, quality of life and functional outcomes between groups were not clinically different. ETAC had fewer complications and episodes of recurrence compared with open surgery. This evidence reinforces the need to critically evaluate new technology before widespread clinical use.

An arthroscopic pleated capsular shift for recurrent anterior dislocation of the shoulder

PURPOSE

This study examined the clinical results of an arthroscopic simple pleated capsular shift to treat severe recurrent anterior dislocation of the shoulder.

METHODS

Twenty-four patients with anterior labroligamentous periosteal sleeve avulsion or advanced lesions who underwent an arthroscopic simple pleated capsular shift were included in this study. To create an arthroscopic simple pleated capsular shift, redundant capsules, including glenohumeral ligaments, were brought at least 1 cm lateral and 1 cm inferior and shifted to the prepared glenoid. Four sutures were made at the 5, 4, 3, and 1-2 o'clock positions with four anchors. Clinical results were evaluated using a visual analog scale (VAS), ROWE scores, active motion, and return to activity. Statistical analyses were carried out using paired t tests.

RESULTS

Three out of 24 patients had complaints. Two patients with recurrent instability underwent a repeat surgery, while the other patient complained of a stiff shoulder. There was a significant improvement in the VAS and ROWE scores post-operatively versus pre-operatively (p < 0.001, p < 0.001, respectively), but no significant differences in active motion except for external rotation, which decreased post-operatively (p = 0.02).

CONCLUSIONS

In patients with severe recurrent anterior dislocation, simple pleated capsular shift provided a reliable result. Four capsular shift sutures, 1 cm lateral and 1 cm inferior from the glenoid, were sufficient to reduce shoulder joint volume and restore stability. The arthroscopic capsular shift could be an alternative method in the case of no available labral lesion for repair.

LEVEL OF EVIDENCE

Case series, Therapeutic, Level IV.

Management of multidirectional instability of the shoulder

Multidirectional shoulder instability is defined as symptomatic instability in two or more directions. Instability occurs when static and dynamic shoulder stabilizers become incompetent due to congenital or acquired means. Nonspecific activity-related pain and decreased athletic performance are common presenting complaints. Clinical suspicion for instability is essential for timely diagnosis. Several examination techniques can be used to identify increased glenohumeral translation. It is critical to distinguish increased laxity from instability. Initial management begins with therapeutic rehabilitation. If surgical management is required, capsular plication has been used successfully. Advanced arthroscopic techniques offer several advantages over traditional open approaches and may have similar outcomes. The role of rotator interval capsular plication is controversial, but it may be used to augment capsular plication in patients with specific patterns of instability. Despite encouraging results, outcomes remain inferior to those associated with traumatic unidirectional instability.

Arthroscopic capsular shift technique and volume reduction

Multidirectional instability is very complex pathology. Excessively redundant capsule is one of the important reasons causing symptomatic laxity in multiple planes. Arthroscopic techniques are not able to reproduce the potential of open methods to reduce the joint volume. Most of the studies based their measurements on cadaver model. The aim of the study was to develop simple and reproducible technique to perform arthroscopic capsular shift and measure its volume reduction potential in both cadaveric and clinical setting. Technique is described in the paper. Capsular shift was applied both in cadaver and clinical scenario. Based on group of 5 cadaver shoulder specimen, glenohumeral joint volume was reduced from average of 19.4 ± 7.8 ml to 11.9 ± 4.5 ml following arthroscopic capsular shift (37.9% volume reduction). Clinical material consisted of 12 consecutive patients shoulder with instability and joint laxity undergoing the arthroscopic capsular shift. Average glenohumeral volume before capsular shift was 43.5 ± 10 ml and was reduced to 17.5 ± 4.3 ml (58.8% volume reduction). Arthroscopic capsular shift presented in this paper seems to be relatively easy to perform and safe procedure. The technique provides significant decrease in joint volume in both cadaveric and clinical parts of the study.

Thermal shrinkage for shoulder instability

Thermal capsular shrinkage was popular for the treatment of shoulder instability, despite a paucity of outcomes data in the literature defining the indications for this procedure or supporting its long-term efficacy. The purpose of this study was to perform a clinical evaluation of radiofrequency thermal capsular shrinkage for the treatment of shoulder instability, with a minimum 2-year follow-up. From 1999 to 2001, 101 consecutive patients with mild to moderate shoulder instability underwent shoulder stabilization surgery with thermal capsular shrinkage using a monopolar radiofrequency device. Follow-up included a subjective outcome questionnaire, discussion of pain, instability, and activity level. Mean follow-up was 3.3 years (range 2.0-4.7 years). The thermal capsular shrinkage procedure failed due to instability and/or pain in 31% of shoulders at a mean time of 39 months. In patients with unidirectional anterior instability and those with concomitant labral repair, the procedure proved effective. Patients with multidirectional instability had moderate success. In contrast, four of five patients with isolated posterior instability failed. Thermal capsular shrinkage has been advocated for the treatment of shoulder instability, particularly mild to moderate capsular laxity. The ease of the procedure makes it attractive. However, our retrospective review revealed an overall failure rate of 31% in 80 patients with 2-year minimum follow-up. This mid- to long-term cohort study adds to the literature lacking support for thermal capsulorrhaphy in general, particularly posterior instability.

ELECTRONIC SUPPLEMENTARY MATERIAL

The online version of this article (doi:10.1007/s11420-010-9187-7) contains supplementary material, which is available to authorized users.

Posterior instability of the shoulder: diagnosis and management

Recurrent posterior instability of the shoulder can be difficult to diagnose and technically challenging to treat. Although not as common as anterior instability, recurrent posterior shoulder instability is prevalent among certain demographic and sporting groups, and may be overlooked if one is not aware of the typical examination and radiographic findings. The diagnosis itself can be difficult as patients typically present with vague or confusing symptoms, and treatment has evolved from open to arthroscopic surgical techniques. This article is intended to review the anatomy and biomechanics associated with posterior shoulder instability, to discuss the pathogenesis and presentation of posterior instability, and to describe the variety of treatment options and clinical results.

Sequential volume reduction with capsular plications: relationship between cumulative size of plications and volumetric reduction for multidirectional instability of the shoulder

PURPOSE

To quantify the relationship between the amount of shoulder capsule imbricated with a simple stitch and the degree of glenohumeral volume reduction in a multidirectional instability model. Secondary purposes were to identify the number of arthroscopic plication stitches required to reduce the shoulder volume equal to that of an open lateral-based inferior capsular shift and to compare volume reductions between suture anchor and suture-only capsular plication stitches.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twelve fresh-frozen cadaveric shoulders (mean age, 64.4 years) were dissected to the level of the rotator cuff. A viscous liquid was injected into each joint, and measurements were taken before and after six 1-cm arthroscopic capsular plication stitches were performed. The sizes of the capsular plications were measured to quantify the amount of capsule imbricated with each simple stitch. A repeated random-intercept regression model was fitted for each outcome, with significance set at P = .05.

RESULTS

There was a near-linear relationship, with each 1 cm of total plication equaling 10% volume reduction up to 4.0 cm. After this, each additional 1-cm plication stitch resulted in 2% to 6% more reduction (mean, 4%). Five simple plication stitches reduced the volume by 52% in the suture anchor group and 49% in the suture-only group. The suture anchor achieved 3% greater volumetric reduction than the suture-only plication stitches, but this effect was not statistically significant (P = .06). Conclusion/

CLINICAL RELEVANCE

A 1-cm capsular plication stitch results in a roughly 10% volume reduction of the glenohumeral joint. Five simple capsular plication stitches result in a volume reduction equivalent to an open lateral-based capsular shift.

Shoulder instability in patients with joint hyperlaxity

Generalized ligamentous hyperlaxity and glenohumeral joint instability are common conditions that exhibit a spectrum of diverse clinical forms and may coexist in the same patient. No single diagnostic test can confirm the presence of these disorders, and a careful clinical assessment is important. Unlike patients with traumatic shoulder instability, patients with hyperlaxity and instability are more likely to experience episodes of recurrent subluxation than they are to have recurrent dislocation. They are more likely to have instability in more than one anatomic plane, and they usually do not have the soft-tissue and osseous lesions associated with traumatic instability. Shoulder symptoms in a patient with hyperlaxity are not always due to instability; other pathological conditions may coexist, with rotator cuff impingement being the most common. Most patients with hyperlaxity have a reduction in instability symptoms after nonoperative treatment, including physical therapy, activity modification, and additional psychological support when necessary. Operative treatment provides reproducibly good results for patients with hyperlaxity who do not respond to a prolonged program of nonoperative measures. Open inferior capsular shift remains the gold standard of operative treatment, although arthroscopic capsular shift and plication procedures are now producing comparable results. Thermal capsulorrhaphy is associated with unacceptably high failure rates and postoperative complications and cannot be recommended as a treatment.

An analysis of capsular area in patients with anterior, posterior, and multidirectional shoulder instability

BACKGROUND

Although increased capsular volume has been implicated in shoulder instability, there is a paucity of clinical evidence to quantify the size of the capsule with specific instability conditions of the shoulder.

HYPOTHESIS

Shoulder capsular area, as measured by magnetic resonance arthrography, is increased with specific patterns of shoulder instability.

STUDY DESIGN

Cross-sectional study; Level of evidence, 4.

METHODS

During an 8-month period, all patients with a diagnosis of anterior (n = 19), posterior (n = 14), or multidirectional (n = 13) instability of the shoulder and who were assessed with a magnetic resonance arthrogram were reviewed. A group of 10 control patients without clinical instability were also identified. The magnetic resonance arthrograms of all groups were randomly mixed, and 5 reviewers recorded measures of capsular length and area and determined labral abnormalities. The magnetic resonance arthrogram measurements were compared between groups, and interobserver agreement was determined.

RESULTS

The cross-sectional area of the capsule was increased in patients with posterior (P = .017) or multidirectional instability (P = .021) versus controls, but not in patients with anterior instability. Additionally, the posteroinferior cross-sectional area was increased in patients with posterior (P = .001), multidirectional (P = .003), and anterior (P = .008) instability. In patients with a posterior labral tear, the mean axial (P = .043) and mean posteroinferior sagittal cross-sectional area (P = .011) was increased, but there were no differences in cross-sectional area for those with an anterior labral tear. The overall interobserver reliability was very good (correlation coefficient range, 0.68-0.94).

CONCLUSION

Our results reinforce the concept that capsular elongation and laxity, either preexisting or acquired, play a role in certain instability conditions of the shoulder. Additional work is needed to determine how to correlate surgical decision making with the cross-sectional area measurements demonstrated in this study.

Arthroscopic multi-pleated capsular plication compared with open inferior capsular shift for reduction of shoulder volume in a cadaveric model

PURPOSE

The purpose of this study was to compare a new arthroscopic technique for capsular plication with the standard open inferior capsular shift for reducing volume in a multidirectional instability model.

METHODS

Seven fresh-frozen cadaveric shoulders (mean age, 55 years) were dissected down to the capsule. A viscous liquid was injected into each shoulder joint and the volume measured. An arthroscopic multi-pleated anterior, posterior, and inferior capsular plication was performed through a single anterior and posterior portal by use of bioabsorbable suture anchors. The shoulder joint volume was again measured, and the sutures were then cut to restore the volume back to the original size. A humerus-based capsular release from 4 o'clock to 6 o'clock to the 8-o'clock position (right shoulder) was performed, the capsule shifted, and the volume recorded. A repeated-measures analysis of variance test was used with significance set at P = .05.

RESULTS

The mean baseline shoulder volume was 20 +/- 9 mL (range, 10 to 35 mL). The arthroscopic plication resulted in a mean decrease of 58% +/- 12%. The open inferior capsular shift resulted in a mean difference of 45% +/- 11%. There was a significant decrease in volume between the arthroscopic and open capsular shifts (P = .006, beta = .92).

CONCLUSIONS

This study proved our hypothesis that with this new arthroscopic technique for capsular plication, arthroscopic volume reduction can be achieved at least as well as with the standard open technique.

CLINICAL RELEVANCE

As the clinical results in the literature improve with improvements in arthroscopic techniques for treating shoulder instability, this arthroscopic method of repair could become invaluable in overcoming the challenge of capsular volume reduction when addressing multidirectional shoulder instability arthroscopically.

Electrothermal arthroscopic shoulder capsulorrhaphy: a minimum 2-year follow-up

BACKGROUND

Few studies have documented the outcomes of thermal capsulorrhaphy for shoulder instability.

PURPOSE

To examine prospective evaluate outcomes of the first 100 patients with glenohumeral instability treated with thermal capsulorrhaphy.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Between 1997 and 1999, 85 of 100 patients treated with thermal capsulorrhaphy for glenohumeral instability were available for review at 2-year minimum follow-up (average, 4 years). Fifty-one patients suffered from anterior instability; 24 had an associated Bankart lesion. Ten patients demonstrated posterior instability; 1 had an associated reverse Bankart lesion. Seventeen patients had multidirectional instability; 8 had an associated Bankart lesion. Seven patients demonstrated anterior and posterior instability without an inferior component; 2 had an associated Bankart lesion. Failures were defined as shoulders requiring revision stabilization (14) or with recurrent instability (18), recalcitrant pain (3), or stiffness (2).

RESULTS

Forty-eight of 85 procedures were successful, and 37 of 85 failed. For patients with anterior instability plus a Bankart lesion, 7 of 24 (26%) had failed results. For those with anterior instability without a Bankart lesion, 10 of 27 (33%) had failed results. The failure rates for posterior, multidirectional instability, and anteroposterior were 60% (6/10), 59% (10/17), and 57% (4/7), respectively. Of the 48 successes, mean preoperative American Shoulder and Elbow Surgeons score improved from 71 to 96 postoperatively, and patient satisfaction was 9.1 on a 10-point scale.

CONCLUSION

Because of the high failure rates, we now augment thermal capsulorrhaphy with capsular plication and/or rotator interval closure in cases of posterior and multidirectional instability and have lengthened the initial immobilization period to improve outcomes. Failure rates for thermal capsulorrhaphy, even with labral repairs, are high especially for shoulders with multidirectional instability and posterior instability. When procedures were successful, however, patients were very satisfied with significant improvements in American Shoulder and Elbow Surgeons scores.

Open and arthroscopic treatment of multidirectional instability of the shoulder

Multidirectional instability of the shoulder can be a difficult diagnostic and therapeutic dilemma for orthopaedic surgeons. First described by Neer and Foster, the mainstay of treatment is usually conservative, with most patients doing very well with nonoperative management. In patients with recalcitrant symptoms, surgical treatment primarily has been aimed at addressing the pathologically increased capsular volume. Newer studies suggest that the pathology also includes abnormal labral morphology and perhaps inadequate neuromuscular control. The arthroscopic treatment of multidirectional instability has come to have comparable results to open techniques when the multifactorial nature of the disease is recognized and the multiple techniques are used in combination to fully treat all pathology. Thermal capsulorrhaphy cannot be recommended at this time, except perhaps as an adjunct to other capsular plication or capsulorrhaphy techniques. The advantages of a less invasive procedure make arthroscopic capsular plication attractive, but it is associated with increased technical difficulty and a steep learning curve. Further studies are needed to distinguish a clear advantage of one over the other. Regardless of the technique used, the key to success is addressing the capsular laxity and redundancy to restore anatomic capsuloligamentous tension without overconstraining the shoulder.

Fluid temperatures during radiofrequency use in shoulder arthroscopy: a cadaveric study

Cadaveric shoulders underwent thermal capsulorrhaphy and subacromial decompression with 3 different commercially available radiofrequency (RF) devices to evaluate local and regional fluid temperatures while arthroscopic procedures were being performed. Fifteen completely thawed fresh-frozen shoulders underwent both thermal capsulorrhaphy and subacromial decompression. During thermal capsulorrhaphy, Fluoroptic mini-thermometer probes (Luxtron model 3000) were placed in the inflow bag; in the glenohumeral joint, near the inferior glenohumeral ligament; and on the RF wand. During subacromial decompression, the temperature probes were placed in the anterior and posterior subacromial space, as well as in the inflow bag and on the RF wand. All data were initially analyzed by use of analysis of variance, followed by pairwise comparison, adjusted for multiple testing by use of the Scheffé method. Mean fluid temperatures (in degrees Celsius [+/- SD]) were highest at the RF wand during both capsulorrhaphy and subacromial decompression. Mean fluid temperatures were much lower at other recorded sites. In this model, we show no deleterious elevation in arthroscopic fluid temperature while performing thermal capsulorrhaphy or subacromial decompression using any of the 3 devices at their recommended settings.

Thermal capsulorrhaphy for the treatment of shoulder instability

Thermal capsulorrhaphy has been used to treat many different types of shoulder instability, including multidirectional instability, unidirectional instability, and microinstability in overhead-throwing athletes. A device that delivers laser energy or radiofrequency energy to the capsule tissue causes the collagen to denature and the capsule to shrink. The optimal temperature to achieve the most shrinkage without causing necrosis of the tissue is between 65 degrees and 75 degrees centigrade. This treatment causes a significant decrease in mechanical stiffness for the first 2 weeks, and then, after the tissue undergoes active cellular repair from the surrounding uninjured tissue, the mechanical properties return to near normal by 12 weeks. If the thermal energy is applied in a grid pattern, then the tissue heals with more stiffness by 6 weeks. Clinical studies on thermal capsulorrhaphy for the treatment of multidirectional instability have shown a high rate of recurrent instability (12%-64%). The clinical studies on unidirectional instability showed much better recurrence rates (4%-25%), but because most of the patients also underwent concomitant Bankart repairs and superior labral anterior posterior lesion repairs, the efficacy of the thermal treatment cannot be ascertained. A randomized controlled trial would be needed to assess whether instability with Bankart lesions requires augmentation with thermal capsulorrhaphy. For the patients with microinstability who are overhead-throwing athletes, thermal capsulorrhaphy has shown varying results from a 97% rate of return to sports to a 62% rate of return to sports. Complications of this technique include temporary nerve injuries that usually involve the sensory branch of the axillary nerve and thermal necrosis of the capsule, which is rare.

Volume analysis of arthroscopic capsular shift

PURPOSE

To determine how much volume reduction can be obtained with varying amounts of arthroscopic capsular plication.

METHODS

Six fresh-frozen, cadaveric specimens were used. Specimens were rejected if a rotator cuff tear was present. The volume of each shoulder joint was measured under 3 conditions: no capsular shift, 5-mm capsular shift, and 10-mm capsular shift. For each shift, 4 sutures were placed arthroscopically, 2 anteriorly and 2 posteriorly. Repeated measures were used to confirm the validity of the measurements. Data were analyzed with parametric and nonparametric tests.

RESULTS

The average percentage of volume reduction at 5 mm of capsular plication from control was 16.2% (range, 9.7% to 21.5%). The percentage of volume reduction from control to 10 mm of capsular plication averaged 33.7% (range, 25.3% to 44.6%). Statistical significance was found with both parametric (P < .0001) and nonparametric tests (P < .0313).

CONCLUSIONS

The current study found that capsular volume reduction was related to the amount of capsular plication with reproducible results. Capsular plication can produce volume reduction comparable to other techniques.

CLINICAL RELEVANCE

The data could be used to determine the potential number of sutures and amount of tissue plication needed for the amount of laxity found at surgery.

A multi-centre randomized controlled trial comparing electrothermal arthroscopic capsulorrhaphy versus open inferior capsular shift for patients with shoulder instability: protocol implementation and interim performance: lessons learned from conducting a multi-centre RCT [ISRCTN68224911; NCT00251160]

BACKGROUND

The shoulder is the most frequently dislocated joint in the body. Multiple causes and pathologies account for the various types of shoulder instability. Multi-directional instability (MDI) and multi-directional laxity with antero-inferior instability (MDL-AII) are similar in pathology, less common and more difficult to treat. These instabilities are caused by ligamentous capsular redundancy. When non-operative management fails for these patients, quality of life is significantly impaired and surgical treatment is required to tighten the ligaments and joint capsule. The current reference (gold) standard treatment for MDI/MDL-AII is an open inferior capsular shift (ICS) surgical procedure. An alternative treatment involves arthroscopic thermal shrinkage of redundant capsular tissue to tighten the joint. However, there is a lack of scientific evidence to support the use of this technique called, electrothermal arthroscopic capsulorrhaphy (ETAC). This trial will compare the effectiveness of ETAC to open ICS in patients with MDI and MDL-AII, using patient-based quality of life outcome assessments.

METHODS

This study is a multi-centre randomized clinical trial with a calculated sample size of 58 patients (p = 0.05, 80% power). Eligible patients are clinically diagnosed with MDI or MDL-AII and have failed standardized non-operative management. A diagnostic shoulder arthroscopy is performed to confirm eligibility, followed by intra-operative randomization to the ETAC or ICS surgical procedure. The primary outcome is the disease-specific quality of life questionnaire (Western Ontario Shoulder Instability Index), measured at baseline, 3, 6, 12 and 24 months. Secondary outcomes include shoulder-specific measures (American Shoulder and Elbow Surgeons Score and Constant Score). Other outcomes include recurrent instability, complications and operative time. The outcome measurements will be compared on an intention-to-treat basis, using two-sample independent t-tests to assess statistical significance. A Generalized Estimated Equations (GEE) analysis will determine whether there is an effect over time.

DISCUSSION

This ongoing trial has encountered unexpected operational and practical issues, including slow patient enrollment due to high intra-operative exclusion rates. However, the authors have a greater understanding of multi-directional laxity in the shoulder and anticipate the results of this trial will provide the medical community with the best scientific clinical evidence on the efficacy of ETAC compared to open ICS.

Thermal capsulorrhaphy

The initial wave of enthusiasm for thermal capsulorrhaphy has subsided. Long-term clinical data were lacking until D'Alessandro et al's prospective study indicated the results were not as promising as the previously reported short-term studies. Complications including obliteration or attenuation of capsular tissue, axillary nerve injury, and chondrolysis have all been reported in recent years further raising concern about the widespread use of this procedure. The inexact nature of how much "shrinkage" is being performed has led surgeons to further develop surgical technique in capsular plication, shift, or advancement. Although it remains to be seen if these techniques will lead to good clinical outcomes, it appears that they more closely resemble the original operative procedure-anterior capsular shift.