The antero-inferior (transmuscular) approach for arthroscopic repair of the Bankart lesion: an anatomic and clinical study

The safety and efficacy of 2 anterior-inferior portals for arthroscopic repair of anterior humeral avulsion of the glenohumeral ligament: cadaveric comparison

BACKGROUND

Humeral avulsion of the glenohumeral ligament (HAGL) lesions are associated with shoulder instability. Arthroscopic repair of anterior HAGL lesions typically requires the placement of an anterior-inferior (5-o'clock) portal, with different variations of this portal described. The purpose of this study was to determine the efficacy of described anterior-inferior shoulder arthroscopy portals for arthroscopic anterior HAGL repair, as well as evaluate the safety of these portals with respect to the surrounding neurovascular structures. Additionally, we sought to evaluate the effect of arm adduction vs. standard abduction during anterior-inferior portal creation.

METHODS

HAGL lesions were created and repaired using an all-arthroscopic technique in 12 cadaveric shoulders (matched pairs). Half of the repairs were performed using a standard 5-o'clock portal, whereas the other half of the matched pairs were repaired using a medialized 5-o'clock portal. Repairs were timed, and the number of anchor pullouts was recorded. The shoulders were subsequently dissected to measure the proximity of the portal to the cephalic vein, musculocutaneous nerve, axillary nerve, and lateral cord of the brachial plexus.

RESULTS

The average time for HAGL repair was 18.0 ± 4.6 minutes. Repair times using the medial 5-o'clock portal (19.0 ± 3.3 minutes) vs. standard 5-o'clock portal (16.2 ± 5.8 minutes) were not significantly different (P = .37). From abduction to adduction, the cephalic vein distance from the standard 5-o'clock portal increased from 4.1 ± 4.7 mm to 5.2 ± 5.4 mm (P = .02); musculocutaneous nerve distance, from 14.4 ± 9.8 mm to 18.1 ± 10.8 mm (P = .005); axillary nerve distance, from 19.2 ± 9.6 mm to 19.8 ± 9.2 mm (P = .12); and distance of the lateral cord of the brachial plexus, 13.8 ± 6.6 mm to 16.7 ± 6.4 mm (P = .0006).

CONCLUSIONS

The arm abduction angle significantly affects the distance of the cephalic vein, musculocutaneous nerve, and lateral cord of the brachial plexus from the anterior-inferior portal, regardless of which portal-standard or medial 5-o'clock portal-is chosen. This portal should be created with the arm in adduction. Arthroscopic HAGL repair can be performed safely, although accurate anchor placement remains a challenge. There was no advantage to use of the medial 5-o'clock portal. With a curved guide, the standard 5-o'clock portal allows for reproducible anchor placement and is recommended for anterior HAGL repairs.

All-arthroscopic glenoid reconstruction by iliac crest bone graft transfer does not affect structural integrity and 3-dimensional volume of the subscapularis muscle

AIM

The subscapularis muscle is an important active stabilizer of the glenohumeral joint. For this radiological study, we investigated if its radiological integrity is affected after arthroscopic glenoid reconstruction. In the technique used, an autologous iliac crest graft is transported through the rotator interval, and the graft is fixed via an antero-inferior portal with compression screws.

METHODS

3 women and 6 men (mean age 31 ± 9 years, min 21, max 46 years) who had a preoperative glenoid deficit of 23% ± 6% (min 13%, max 29%) were included. In a follow-up after an interval of 34 months (min 19, max 50), MRI scans were performed on both shoulders. With ITK-SNAP, a 3D reconstruction software, the volume of the subscapularis muscle in the injured and contralateral shoulder was measured. In addition, signal intensity ratios (PSI) (infraspinatus muscle / cranial subscapularis muscle and infraspinatus muscle / caudal subscapularis muscle) were analyzed and the width of the cranial and caudal portions as well as the length of the subscapularis muscle in the parasagittal plane were determined.

RESULTS

The 3D volume showed no difference between operated and healthy shoulders (p = 0.07), neither did PSI ratios (infraspinatus muscle / cranial subscapularis muscle: p = 1.00, infraspinatus muscle / caudal subscapularis muscle: p = 1.00). In the parasagittal plane, length (p = 0.09) and cranial width (p = 0.23) did not differ. However, the width of the lower muscle was increased in injured shoulders (p = 0.02).

CONCLUSION

In this cohort, no relevant volume loss could be found after arthroscopic glenoid reconstruction. However, a greater width of the lower muscle portion could be identified in the parasagittal plane as a possible indication of scarring.

Anatomic considerations for arthroscopic glenoid reconstruction using iliac crest grafts: a radiologic study

BACKGROUND

Arthroscopic glenoid reconstruction using autografts is an advanced procedure that requires experience and preparation. Knowledge about anatomic pitfalls is therefore important to establish well-positioned portals and prevent neurovascular damage.

METHODS

We included 43 computed tomography scans from 43 patients. The distance between the tip of the coracoid process and a perpendicular line representing the anteroinferior glenoid was measured. From these results an anteroinferior working portal was designed, and the angulation needed for screw insertion to fixate a hypothetical graft was measured. In a second step, 9 patients underwent magnetic resonance imaging scans 34 ± 10 months after glenoid reconstruction, and the distance between the screw approach path and the neurovascular bundle was measured.

RESULTS

In the analyzed scans, average defect size was 23%, and the coracoid process to the anteroinferior glenoid distance was 32 ± 7 mm. We thus hypothesized that a corridor 20 to 30 mm inferior to the coracoid process would be the ideal position for a working portal. Through this portal, 85% of screws could be applied with 0° to 30° angulation. When the postoperative scans were analyzed, the distance from the neurovascular bundle showed an average of 26 ± 6 mm for the superior screw and 21 ± 5 mm for the inferior screw.

CONCLUSIONS

The ideal distance between the coracoid process and an anteroinferior working portal is 32 mm. Having established the portal, instruments should not be inserted pointing in a medial direction of the coracoid process due to the proximity of the neurovascular bundle.

Lesser Tuberosity Osteotomy in Anatomic Total Shoulder Arthroplasty

The deltopectoral exposure has earned the reputation as the “workhorse” approach to the shoulder. Due to the reproducible anatomy and its extensile nature, there is little debate when considering exposure in total shoulder arthroplasty (TSA). Despite this consensus, there is still significant variability in management of the subscapularis. Several repair techniques including a subscapularis tenotomy, peel, and lesser tuberosity osteotomy (LTO) have been developed to ensure healing and optimize function. This article focuses on performing a LTO in anatomic TSA. We will review the surgical technique and advantages in exposure in addition to biomechanical and clinical outcomes.

Arthroscopic Management and Radiographic Interpretation of an Everted Bony Bankart Lesion

Soft tissue injuries are prevalent after traumatic anterior shoulder dislocation. However, bony fractures, often referred to as bony Bankart injuries, are less common. The authors describe the case of a 16-year-old male who displayed a bony Bankart with a unique, everted presentation. The patient presented with left shoulder pain, restricted range of motion, and crepitus. Two weeks prior to physical examination, he sustained a traumatic anterior glenohumeral dislocation after a bicycle accident, which reduced spontaneously. Plain film imaging revealed a bony fragment off the anterior glenoid. Upon critical examination of magnetic resonance imaging axial cuts, the bony fragment was found to be flipped. Intraoperatively, this orientation was confirmed. The fragment was reduced and stabilized in an anatomic position using a double row technique with the capsule then advanced over the top of the fragment using three additional anchors. Imaging four months postoperatively revealed an anatomical reduction of the fragment. To the authors' knowledge, this is the first reported case of bony fragment eversion following traumatic anterior shoulder dislocation. Although the incidence of everted bony fragments following traumatic dislocation is unknown, such a situation presents unique challenges to the orthopedic surgeon. The authors discuss potential eversion mechanisms, fragment identification by imaging, surgical indications, and operative techniques.

Arthroscopic Versus Open Iliac Crest Bone Grafting in Recurrent Anterior Shoulder Instability With Glenoid Bone Loss: A Computed Tomography-Based Quantitative Assessment

PURPOSE

To assess the iliac crest bone graft (ICBG) position in the en-face view and axial plane comparing arthroscopic with open procedures.

METHODS

A total of 40 consecutive patients with recurrent anterior shoulder instability and glenoid bone loss over 10% treated by 2 independent orthopaedic departments were included. Two independent observers analyzed preoperative and immediate postoperative computed tomography scans of 20 open (group O) and 20 arthroscopic (group A) procedures. Defect and ICBG characteristics of the J-shaped graft in the en-face view and axial plane were manually assessed by multiplanar reconstructed computed tomography scans. Variances in terms of graft positioning were analyzed.

RESULTS

No significant variances in arthroscopic graft positioning were observed. The graft position in the en-face view was comparable in both groups, with the superior extent of the arthroscopic graft (40° ± 9° [inferior extent, 139° ± 16°]) lying significantly higher than the superior extent in group O (50° ± 13°, P = .005 [inferior extent, 147° ± 21°; P = .178]). The covered glenoid defect size was above 95% (98% ± 1% in group O vs 95% ± 2% in group A, P = .001). The arthroscopic graft in the axial plane showed a significantly steeper impaction angle (34.8° ± 7.8° vs 26.9° ± 9.9°, P = .010), with a significantly increased medial offset compared with group O (6.6 ± 1.7 mm vs 5.4 ± 1.3 mm, P = .024). The mediolateral step formation, however, was not significantly different (2.9 ± 1.1 mm in group A vs 3.2 ± 0.8 mm in group O, P = .289). The interobserver reliability was very good for all measurements (R = 0.969; 95% confidence interval, 0.965-0.972).

CONCLUSIONS

Positioning of the arthroscopic ICBG in the en-face view and axial plane is comparable to that of the open technique. Good glenoid defect coverage and glenoid concavity reconstruction can be achieved with the arthroscopic technique. The main difference compared with the open procedure is the significantly steeper impaction angle.

LEVEL OF EVIDENCE

Level III, case-control study.

Management of the subscapularis tendon during total shoulder arthroplasty

Use of total shoulder arthroplasty has significantly increased during the past decade. For anatomic total shoulder arthroplasty, controversy exists regarding the best technique for detachment and repair of the subscapularis tendon. Options include tendon tenotomy, peel, lesser tuberosity osteotomy, and even subscapularis-sparing techniques. Inadequate healing of the subscapularis tendon can lead to postoperative pain, weakness, and instability. This review discusses the subscapularis pathoanatomy, different techniques for releasing and repairing the tendon, and reports biomechanical and clinical outcomes for each technique after total shoulder arthroplasty.

A Biomechanical Analysis of Anchor Placement for Bankart Repair: Effect of Portal Placement

During arthroscopic Bankart repair, penetration of suture anchors through the far cortex can compromise the initial biomechanical characteristics of anchor stability and repair integrity. This study compared the placement of suture anchors through a low anterior-inferior rotator interval portal (AI) vs a trans-subscapularis portal to evaluate the rate of anchor perforation as well as biomechanical strength. Ten matched pairs of cadaveric shoulders were randomized to an AI or a trans-subscapularis portal for placement of suture anchors at the 3 o'clock and 5:30 positions. The following measurements were obtained: (1) distance from the portal to the cephalic vein; (2) presence and length of anchor penetration through the inferior glenoid; and (3) ultimate failure strength of the anchors. The distance from the portal to the cephalic vein was significantly greater with the AI vs the trans-subscapularis portal across all specimens (29.9 vs 11.2 mm, P<.05). The rate of anchor penetration was significantly increased in the AI group vs the trans-subscapularis group at the 5:30 position (60% vs 10%, P=.014) but not at the 3 o'clock position (P=.33). Mean pullout strength of the anchors at the 5:30 position trended higher in the trans-subscapularis group, but the difference was not significant (132.8 vs 112.6 N, P=.18). The cephalic vein is closer to the trans-subscapularis portal than to the AI, but is at a safe distance. Both the rate and the degree of glenoid suture anchor penetration were lower with the trans-subscapularis portal compared with the AI at the 5:30 position. Placing anchors through the trans-subscapularis portal provides a safe alternative method, with improved positioning of the inferiormost anchor compared with the traditional AI.

Arthroscopic Implant-Free Bone Grafting for Shoulder Instability With Glenoid Bone Loss: Clinical and Radiological Outcome at a Minimum 2-Year Follow-up

BACKGROUND

Posttraumatic anteroinferior shoulder dislocations with concomitant glenoid bone loss show high recurrence rates. The open J-bone graft technique for implant-less anatomic restoration of bony glenoid structure has previously been described, whereas results of arthroscopic techniques are currently not available.

PURPOSE

To evaluate clinical and radiological outcome after arthroscopic anatomic reconstruction of the glenoid for recurrent anteroinferior glenohumeral instability.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Fifteen shoulders of 14 patients with recurrent anteroinferior shoulder instability were prospectively followed after glenoid reconstruction with a modified arthroscopic, implant-free J-bone graft. Preoperatively, the instability severity index score was documented. Patients were followed for a minimum of 2 years using the Rowe score and the Constant score. Subjective outcome was assessed using a visual analog scale (VAS) for pain and the subjective shoulder value for sports (SSVS); satisfaction with procedure outcome was also rated. Range of motion was recorded. Incidence of recurrent instability, defined as dislocation, subluxation, or persistent apprehensiveness, was documented. Pre- and postoperative (1 day and 3, 12, and 24 months) computed tomographic images were used to evaluate glenoid bone loss, reconstruction of the glenoid, and graft remodeling.

RESULTS

All preoperative scores (Rowe score: 57.6 ± 14.4; Constant score: 70.9 ± 8.9; VAS: 4.4 ± 2.6; SSVS: 31.4% ± 19.5%) were significantly (P ≤ .02) improved at final follow-up (Rowe score: 98.6 ± 1.5; Constant score: 96.3 ± 3.9; VAS: 0.2 ± 0.6; SSVS: 95.6% ± 3.8%). The preoperative glenoid area (82.1% ± 4.5%) was significantly increased immediately after surgery to 99.2% ± 6.6% (P < .001). After a physiological remodeling process, the glenoid area remained significantly increased at the latest follow-up (89.5 ± 3.2%, P < .001). J-bone grafting successfully restored glenoid concavity by significantly increasing concavity extent and depth from preoperative (19.8 ± 2.1 and 0.9 ± 0.6 mm, respectively) to postoperative (24.0 ± 2.1 and 2.1 ± 0.8 mm, respectively) (P < .001). There were no recurrent instabilities. One traumatic graft fracture occurred during the follow-up period.

CONCLUSION

The arthroscopic J-bone graft technique permits minimally invasive reconstruction of anteroinferior glenoid defects and provided excellent early clinical outcome without recurrent instability in posttraumatic shoulder dislocations. A physiological remodeling process leads to restoration of a more natural glenoid anatomy.

A new subscapular sling operation to stabilize the shoulder. A cadaver study

Introduction

A new arthroscopic shoulder stabilisation procedure is proposed, which for some patients could be an alternative to the arthroscopic Latarjet procedure.

Methods

The objective was to stabilize the shoulder by making a sling around the subscapularis tendon, using a hamstring graft and enhancing the anterior rim of the glenoid with the same graft. The anatomical feasibility of the surgical procedure was tested to establish the surgical method.

Results

Four surgeons performed the surgery on six cadavers. After the surgery the cadavers were dissected to visualize the result. The sling was placed according to the intention and the nerves in the area (axillary and musculocutaneus) were not at risk, nor had they altered position during the procedure.

Conclusion

The procedure is technically feasible and the risk of complications seems low. This procedure could be an alternative to the Latarjet procedure and to other operations used for anterior instability of the shoulder. A biomechanical study will be performed as the next stage of the development.

Clinical relevance

This procedure could be an alternative to the Latarjet procedure and to other operations used for anterior instability of the shoulder.

Trial registration

2012/1978/REK sør-øst

Trans-subscapularis portal versus low-anterior portal for low anchor placement on the inferior glenoid fossa: a cadaveric shoulder study with computed tomographic analysis

PURPOSE

The purpose of this study was to evaluate the accuracy of inserting a glenoid anchor at the 5:30 clockface position using a trans-subscapularis (TSS) portal versus a low anterior (LA) portal.

METHODS

Five surgeons (T.D., J.C., C.V., D.J.O-H., J.S.T.) placed a single anchor in 20 fresh-frozen cadaveric shoulders. In each of 2 shoulders, surgeons used an LA portal to insert the anchor, whereas in 2 shoulders a TSS portal was used. Surgeons were directed to place the anchor at the 5:30 position at an angle 45° to the glenoid surface (axial plane) and passing perpendicular to the glenoid rim in the coronal plane. Shoulders were then dissected and computed tomographic (CT) scans obtained. Anchor position relative to the clockface was documented by 2 blinded assessors, as was the angle of insertion in the axial and coronal planes. Statistical significance was calculated with a Student t test for paired samples (confidence interval [CI], 95%; significance, P < .05).

RESULTS

The average deviation from the 5:30 position was 48 minutes (standard deviation [SD], 31 minutes) for the LA portal (average position, 4:42 o'clock) versus 28.5 minutes (SD, 19 minutes) for the TSS group (average position, 5:02 o'clock) (P = .15). The average angle of anchor insertion in the axial plane was 67.2° (SD, 19°) for the LA portal versus 62.8° (SD, 14°) for the TSS portal (P = .49), whereas the average angle of insertion in the coronal plane was 31.3° (SD, 14°) of inferior angulation in the LA group and 14.3° (SD, 8°) of inferior angulation in the TSS group (P = .009). Of the anchors inserted, 9 of 20 (45%) showed evidence of far-cortical perforation. No difference in cortical perforation was seen between the 2 portals, with perforation more likely with anchors inserted greater than 45° in the axial plane (8 of 20) than with those inserted less than 45° (1 of 20) (P = .02).

CONCLUSIONS

The use of a TSS portal improves the angle of approach to the inferior glenoid rim in comparison with an LA portal, reducing the acuity of the angle of insertion in the coronal plane.

CLINICAL RELEVANCE

The TSS portal is an option for surgeons performing arthroscopic Bankart repair using anchors low on the glenoid rim.

Outcomes of arthroscopic anterior shoulder instability in the beach chair versus lateral decubitus position: a systematic review and meta-regression analysis

PURPOSE

This study aimed to systematically review the clinical outcomes and recurrence rates after arthroscopic anterior shoulder stabilization in the beach chair (BC) and lateral decubitus (LD) positions.

METHODS

The authors performed a systematic review of multiple medical databases using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. All English-language literature from 1990 to 2013 reporting clinical outcomes after arthroscopic anterior shoulder stabilization with suture anchors or tacks with a minimum 2-year follow-up period were reviewed by 2 independent reviewers. Data on recurrent instability rate, return to activity/sport, range of motion, and subjective outcome measures were collected. Study methodological quality was evaluated with the Modified Coleman Methodology Score (MCMS) and the Quality Appraisal Tool (QAT). To quantify the structured review of observational data, meta-analytic statistical methods were used.

RESULTS

Sixty-four studies (38 BC position, 26 LD position) met inclusion criteria. A total of 3,668 shoulders were included, with 2,211 of patients in the BC position (average age, 26.7 ± 3.8 years; 84.5% male sex) and 1,457 patients in the LD position (average age, 26.0 ± 3.0 years; 82.7% male sex). The average follow-up was 49.8 ± 29.5 months in the BC group compared with 38.7 ± 23.3 months in the LD group. Average overall recurrent instability rates were 14.65 ± 8.4% in the BC group (range, 0% to 38%) compared with 8.5% ± 7.1% in the LD group (range, 0% to 30%; P = .002). The average postoperative loss in external rotation motion (in abduction) was reported in 19 studies in the BC group and in13 studies in the LD group, with an average loss of 2.4° ± 1.0° and 3.6° ± 2.6° in each group, respectively (P > .05).

CONCLUSIONS

Excellent clinical outcomes with low recurrence rates can be obtained after arthroscopic anterior shoulder stabilization in either the BC or the LD position; however, lower recurrence rates are noted in the LD position. Additional long-term randomized clinical trials comparing these positions are needed to better understand the potential advantages and disadvantages of each position.

LEVEL OF EVIDENCE

Level IV, systematic review of studies with Level I through Level IV evidence.

Arthroscopic bankart repair: accessory posterior portal with slotted cannula for lowest capsulolabral access

We present a novel technique for safe establishment of the accessory posterior portal using a slotted cannula. Arthroscopic Bankart repair is a common procedure. A variety of arthroscopic techniques have been described in the literature, commonly using the posterior portal for visualization and the anterior portal with a working cannula. The accessory posterior portal enables elegant access to the lower part of the capsulolabral junction, a firmer grasp and mobilization of the tissue, quick and easy tool exchange using a slotted cannula, and clearer suture placement because of the flat, direct working angle. The skin incision is made small without the need for an arthroscopic cannula, and the portal location is in a relatively safe zone. The use of the accessory posterior portal along with a slotted cannula shortens the duration of the operative procedure and improves safety and performance.

Inferior suture anchor placement during arthroscopic Bankart repair: influence of portal placement and curved drill guide

BACKGROUND

During arthroscopic Bankart repair, inferior anchor placement is critical to a successful outcome. Low anterior anchors may be placed with a standard straight guide via midglenoid portal, with a straight guide with trans-subscapularis placement, or with curved guide systems. Purpose/

HYPOTHESIS

To evaluate glenoid suture anchor trajectory, position, and biomechanical performance as a function of portal location and insertion technique. It is hypothesized that a trans-subscapularis portal or curved guide will improve anchor position, decrease risk of opposite cortex breach, and confer improved biomechanical properties.

STUDY DESIGN

Controlled laboratory study.

METHODS

Thirty cadaveric shoulders were randomized to 1 of 3 groups: straight guide, midglenoid portal (MG); straight guide, trans-subscapularis portal (TS); and curved guide, midglenoid portal (CG). Three BioRaptor PK 2.3-mm anchors were inserted arthroscopically, with an anchor placed at 3, 5, and 7 o'clock. Specimens were dissected with any anchor perforation of the opposite cortex noted. An "en face" image was used to evaluate actual anchor position on a clockface scale. Each suture anchor underwent cyclic loading (10-60 N, 250 cycles), followed by a load-to-failure test (12.5 mm/s). Fisher exact test and mixed effects regression modeling were used to compare outcomes among groups.

RESULTS

Anchor placement deviated from the desired position by 9.9° ± 11.4° in MG specimens, 11.1° ± 13.8° in TS, and 13.1° ± 14.5° in CG. After dissection, opposite cortex perforation at 5 o'clock occurred in 50% of MG anchors, 0% of TS, and 40% of CG. Of the 90 anchors tested, 17 (19%) failed during cyclic loading, with a similar failure rate across groups (P = .816). The maximum load was significantly higher for the 3-o'clock anchors when compared with the 5-o'clock anchors, regardless of portal or guide (P = .021). For the 5-o'clock position, there were significantly fewer "out" anchors in the TS group versus the CG or MG group (P = .038). There was no statistically significant difference in maximum load among groups at 5 o'clock.

CONCLUSION

Accuracy in suture anchor placement during arthroscopic Bankart repair can vary depending on both portal used and desired position of anchor. The results of the current study indicate that there was no difference in ultimate load to failure among anchors inserted via a midglenoid straight guide, midglenoid curved guide, or percutaneous trans-subscapularis approach. However, midglenoid portal anchors drilled with a straight or curved guide and placed at the 5-o'clock position had significant increased risk of opposite cortex perforation compared with trans-subscapularis percutaneous insertion, with no apparent biomechanical detriment.

CLINICAL RELEVANCE

The findings from this study will facilitate improved understanding of risks and benefits of several techniques for arthroscopic shoulder instability treatment with regard to suture anchor fixation.

Pectoralis major transfer for subscapular deficiency: anatomical study of the relationship between the transferred muscle and the musculocutaneous nerve

PURPOSE

Pectoralis major transfer is indicated for irreparable subscapularis tendon tears. One surgical option is transferring the sternal part of the pectoralis major to the humeral insertion of the subscapularis under the conjoined tendon of the coracobrachialis and biceps muscles. The purpose of this study is to define the anatomical relationship between the transferred tendon and the musculocutaneous nerve.

METHODS

In 52 cadaveric fresh-frozen shoulders, the relevant structures were dissected and a pectoralis major transfer was performed. The relationship between the transferred tendon, the musculocutaneous nerve branches distally and the coracoid process proximally was examined. Measurements were taken at the conjoined tendon level.

RESULTS

The distance between the coracoid process and the most proximal musculocutaneous nerve branch was 54.2 ± 33.2 mm. In 25 cases (48%), the transferred tendon passed freely between both structures. In 16 cases (31%), there was contact distally with the musculocutaneous nerve. In 11 cases (21%), there was contact both proximally with the coracoid process and distally with the musculocutaneous nerve, making a safe transfer impossible.

CONCLUSIONS

When performing a pectoralis major transfer, it is essential to identify the musculocutaneous nerve and its branches. In some cases, a subcoracobicipital transfer may not be feasible and a more superficial transfer should be considered.

All-arthroscopic implant-free iliac crest bone grafting: new technique and case report

Glenoid bone loss is a recognized risk for recurrent instability. Open J-graft augmentation has been reported as a well-established procedure for anterior shoulder instability. Few data are available on arthroscopic techniques for the repair of bony Bankart lesions. We describe an all-arthroscopic implant-free iliac crest bone grafting technique and present the case of a 32-year-old hockey player who underwent glenoid reconstruction using this novel arthroscopic repair technique after 2 failed soft-tissue procedures. After 13 months, the patient reached nearly full range of motion with a slight loss of external rotation. The computed tomography scan showed a restoration of the glenoid cavity and complete healing of the graft.

Arthroscopically assisted fixation of glenoid fractures: a cadaver study to show potential applications of percutaneous screw insertion and anatomic risks

BACKGROUND

Displaced glenoid fractures require reduction and internal fixation to avoid chronic instability or degenerative changes. Arthroscopically assisted percutaneous fixation has been performed successfully for such fractures, avoiding extensive surgical dissection. To assess the application of this new technique, our cadaveric study was designed to show 1) the safe zones of percutaneous screw insertion and 2) the position of bony obstructions to the glenoid.

METHODS

In 18 cadaver shoulders, we performed arthroscopically assisted percutaneous wire insertion into the glenoid using anterior, superior, and posterior approaches. After dissection, distances from wires to the relevant neurovascular structures were recorded, and 95% confidence intervals were calculated. A safe distance was defined as 15 mm. The entry point of each wire and angle of insertion relative to the glenoid clock face was also recorded.

RESULTS

Superior and posterior percutaneous approaches appear to be safe, with minimal risk to the suprascapular vessels and axillary nerve, respectively. The anterior approach injured the cephalic vein in 30% of specimens, and there was a clinically significant risk to the musculocutaneous nerve and inferior branch of the suprascapular nerve. The superior portion of the glenoid is accessible by percutaneous screw insertion between the clock times 7:40 and 2:50, apart from positions occupied by the coracoid (1:05-2:00) and acromion (9:35-10:55).

CONCLUSIONS

Arthroscopic fixation of complex glenoid fractures has had good outcomes in clinical case studies. This cadaveric study shows that percutaneous screw insertion is safe via superior and posterior approaches and feasible for a range of fracture configurations.

Subscapularis management in open shoulder surgery

Management of the subscapularis in open shoulder surgery is a controversial topic. Subscapularis tenotomy has been the traditional approach, but other techniques have recently been developed to preserve the integrity of the subscapularis tendon. These include subscapularis peel, subscapularis split, and lesser tuberosity osteotomy. The biologic healing and biomechanical properties associated with each surgical approach must be evaluated to determine the best option for each patient. A strong, anatomic repair is required to achieve optimal clinical outcomes.

Complications in shoulder arthroscopy

Shoulder arthroscopy is generally a safe and effective method for treating a wide variety of shoulder pathology. Fortunately, complications following shoulder arthroscopy are rare, with reported rates between 4.6% and 10.6%.¹⁻⁷ These rates may be underestimated, as underreporting of complications and varying definitions of the term complication are likely. During shoulder arthroscopy, complications may occur at numerous points. The surgeon must be aware of potential problems and take necessary measures to prevent them. This article describes common complications after arthroscopic shoulder surgery. Although failure of treatment and postoperative stiffness are undesirable outcomes, they are not described.

Arthroscopic three-point double-row repair for acute bony Bankart lesions

After mobilizing anteroinferior osseous Bankart lesion from the glenoid neck, a suture anchor loaded with differently colored non-absorbable braided sutures is placed on the medial edge in the glenoid neck along the rim fracture through the anterior-inferior trans-subscapularis tendon portal. Two same-colored suture limbs on the anchor are then pulled through the labrum using PDS suture shuttling simultaneously. These steps are repeated for the others suture limbs. The two same-color suture limbs located inferiorly are retrieved using the trans-subscapularis tendon portal. Both suture strands are threaded through the eyelet of a PushLock anchor on the distal end of the driver. The anchor is advanced into the pilot hole completely. These steps are repeated for a second anchor at the upper edge of the fracture in the glenoid rim using the anterior portal. This technique confers effective, firm fixation of the bony Bankart lesion by three-point fixation without the suture material crossing the glenoid cavity.

Long-term independent evaluation after arthroscopic extra-articular Bankart repair with absorbable tacks. Surgical technique

BACKGROUND

Several arthroscopic methods have been developed to treat posttraumatic recurrent anterior shoulder instability in an attempt to match the results that can be achieved with open repair. The aim of this study was to perform an independent long-term clinical and radiographic evaluation after extra-articular arthroscopic Bankart repair with use of absorbable tacks (Suretac fixators).

METHODS

Eighty-one consecutive patients with posttraumatic recurrent anterior shoulder instability underwent an extra-articular arthroscopic Bankart procedure. Seventy-one (88%) of the patients were reexamined physically after a median duration of follow-up of 107 months by two independent examiners and constituted the study group. Their clinical and radiographic outcomes were documented.

RESULTS

At the time of follow-up, twenty-seven (38%) of the seventy-one patients had experienced some kind of shoulder instability, although fifteen of them had had a new, clinically relevant shoulder injury. Eleven patients had had subluxation only, and sixteen had had redislocation. Fourteen of the twenty-seven patients had had a single episode of instability. Seven patients had undergone additional surgery to treat shoulder instability. The instability episodes occurred less than two years postoperatively in nine patients, between two and five years postoperatively in twelve, and more than five years postoperatively in six. At the time of final follow-up, the median external rotation in abduction was 90 degrees (range, 0 degrees to 120 degrees ) compared with 95 degrees (range, 70 degrees to 125 degrees ) for the contralateral, uninjured shoulders (p < 0.001). Before the injury, fifty-two patients (73%) participated in overhead or contact sports, whereas thirty-four patients (45%) participated in such activities at the time of follow-up. At the time of follow-up, the drill holes used to implant the absorbable tacks were invisible or hardly visible in fifty-eight (91%) of sixty-four patients for whom radiographs had been made. A marked increase in degenerative changes was noted when follow-up radiographs were compared with the preoperative radiographs.

CONCLUSIONS

This long-term follow-up study of arthroscopic extra-articular Bankart repairs revealed an unexpectedly high number of patients with new episodes of instability. This finding led to a slight modification of the technique. Since most instability episodes occurred after two years, it is important to follow patients for a longer period of time after surgical treatment of recurrent anterior shoulder instability to identify the true recurrence rate.

Arthroscopic screw fixation of large anterior glenoid fractures

Ten patients after traumatic shoulder dislocation with resulting instability due to an acute anterior glenoid fracture involving at least 21 percent of the glenoid length were treated by arthroscopic screw fixation of the fragment. The average fragment size measured 26.2% of the glenoid length. Pre- and postoperative radiographic evaluations were performed with three-dimensional CT scans. A cannulated titanium screw system was used for fragment fixation. All ten patients were followed up radiographically and, by evaluation of the Rowe score, clinically after a minimum of 2 years. At follow-up the Rowe score averaged 94 points. According to the rating scale, seven patients had an excellent result, two patients a good result, and one, fair result. In all patients CT scan confirmed that the fracture had healed in an anatomical position. One patient had one episode of traumatic redislocation with a positive apprehension test at follow up. In one case, removal of the screw was necessary due to mechanical impingement. We recommend this arthroscopic technique allowing for closed reduction and internal screw fixation of large anterior glenoid fractures, ensuring anatomical fracture healing and gleno-humeral joint stability.

Abduction and external rotation in shoulder impingement: an open MR study on healthy volunteers initial experience

PURPOSE

To prospectively evaluate rotator cuff contact with the glenoid in healthy volunteers placed in the unloaded and loaded abduction and external rotation (ABER) positions in an open magnetic resonance (MR) imager.

MATERIALS AND METHODS

The study was institutional review board approved and HIPAA compliant, and informed consent was received. Eight male volunteers with no history of shoulder pain or pathology were imaged in a 0.5-T open MR imager. Volunteers were imaged in an unloaded ABER position with the arm at 90 degrees abduction and in a loaded ABER position, with a 1-kg load that produced an average external rotation of 111 degrees+/-6 (standard deviation). Two radiologists graded rotator cuff contact on a three-point scale. Three-dimensional anatomic models generated from the MR images were used to measure distances. Minimum distances were computed between the tendon insertion sites and the glenoid, acromion, and coracoid for the loaded ABER position. Minimum distances were compared by using a paired Student t test.

RESULTS

In the unloaded ABER position, contact was seen between the infraspinatus and supraspinatus tendons and the glenoid in all eight volunteers. In the loaded ABER position, contact was also observed between the infraspinatus and supraspinatus and the posterior and posterosuperior glenoid, respectively. Deformation of the infraspinatus on the glenoid was seen in four volunteers, whereas supraspinatus deformation was only seen in one volunteer. The minimum distance between the supraspinatus insertion and acromion in the loaded ABER position decreased significantly (P<.01). Supraspinatus tendon to glenoid and infraspinatus tendon to glenoid minimum distances also decreased significantly (P<.01).

CONCLUSION

The unloaded and loaded ABER positions resulted in contact of the supraspinatus and infraspinatus with the glenoid in all volunteers. Distances between the rotator cuff insertion sites and the glenoid decreased in the loaded ABER position.

A comparison of risk between the lateral decubitus and the beach-chair position when establishing an anteroinferior shoulder portal: a cadaveric study

PURPOSE

The purpose of this study was to assess, using a technique that minimally distorts the normal anatomy, the risk of injury when establishing a 5 o'clock shoulder portal in the lateral decubitus versus beach-chair position.

METHODS

The anteroinferior portal was simulated with Kirschner wires (K-w) drilled orthogonally at the 5 o'clock position in 13 fresh frozen human cadaveric shoulders. The neighboring neurovascular structures were identified through an anteroinferior window made in the inferior glenohumeral ligament. Their relations to the K-w and surrounding structures were recorded in both positions.

RESULTS

The median distance from the musculocutaneous nerve to the K-w was shorter in the lateral decubitus position than in the beach chair position (13.16 mm v 20.49 mm, P = .011). The cephalic vein was closer to the portal in the beach-chair position than in the lateral decubitus position (median 8.48 mm v 9.93 mm, P = .039). The axillary nerve was closer to the K-w in the lateral decubitus position than in the beach-chair position (median 21.15 mm v 25.54 mm, P = .03). No differences in the distances from the K-w to the subscapular and anterior circumflex arteries were found when comparing both positions. The mean percentage of subscapular muscle height from its superior border to the K-w was 53.03%.

CONCLUSIONS

This study showed the risk of injury establishing a transubscapular portal in either position. The musculocutaneous nerve and the cephalic vein are the most prone to injury. In general, the beach-chair position proved to be safer.

CLINICAL RELEVANCE

Inserting anchor devices orthogonally would permit stronger fixation but presents the risk of damaging neurovascular structures. This study focused on showing the neurovascular risk of performing full orthogonal insertion. Considering the good results reported with the usual superior-anterior portals, we do not recommend performing a transubscapular portal in routine shoulder arthroscopy.

Musculocutaneous nerve: Histotopographic study and clinical implications

Surgical reconstruction of severe brachial plexus injuries includes nerve grafting and neurotization techniques of the musculocutaneous nerve (MCN) to recover elbow flexion. In treating recurrent anterior shoulder instability, knowledge of the topography of the MCN is important for the margin of safety available during dissection. The present study evaluates the origin and course of the MCN and its branches, and their relationships to bone landmarks. Twelve unembalmed cadavers (50-82 years old) were dissected. A histological study of the MCN and the coracobrachialis muscle (CB) was also carried out. The mean distance (+/-SD) of the MCN from the coracoid process to the origin, points of entry to, and exit from the CB were 2.9 +/- 0.5 cm, 7.7 +/- 2.5 cm, and 11.6 +/- 0.8 cm, respectively. The first two findings were also validated during surgical approaches to the shoulder in 59 subjects. The mean distance of the MCN from the acromion to the origin, points of entry to, and exit from the CB were 6.4 +/- 0.3 cm, 7.7 +/- 0.8 cm, and 10.4 +/- 1.9 cm, respectively. The mean length of the MCN from its origin to the points of entry to and exit from the CB were 6.7 +/- 1.6 cm and 11.0 +/- 1.0 cm, respectively. The mean length of the MCN inside the muscle was 4.4 +/- 1.9 cm. The distance from the coracoid process to the point of entry to the CB and the length of the MCN inside the muscle were inversely related (P < 0.05). The distance from the coracoid process to the point of exit of the MCN was positively correlated with the length of the nerve within the CB (P < 0.05). Histology showed that, during the intramuscular course of the MCN, the epineurium is composed of 4-5 concentrically arranged lamina of connective tissue which shows different dispositions along the circumference of the nerve trunk. On the ventral and dorsal aspects of the nerve the lamina are closely packed, but on the medial and lateral sides they are separated by thin layers of adipose tissue. This uneven disposition of the adipose tissue gives the epineurium an oval profile in transverse section (mean circular factor 0.8). The arrangement of the fibroadipose tissue sheaths may be compared to a "telescope" and may allow compliance between variations of length of CB and the constant course of the MCN. Clinically, a decrease in this "sliding system" may expose the nerve to mechanical effects of muscle contraction, with the possibility of a compression syndrome.

[Contribution to subscapularis nerve supply. 18 dissections]

INTRODUCTION

Dividing the subscapularis muscle along its fibers axis allows approaching the glenohumeral joint. The more medial its division, the more possible injury of its nerve supply.

AIM

The aim of our study was to assess the subscapularis nerve supply through cartography of the entry points of subscapularis nerves from simple landmarks, reproducible by triangulation.

MATERIAL AND METHODS

On 18 formalin-preserved shoulders, after dissection of the subscapularis nerves, distances were measured between entry points of subscapularis nerves and the following landmarks: center of the minor tubercle (tm), upper and lower poles of the glenoid cavity (cgs and cgi), apex of the coracoid process (pc).

RESULTS

There were in average 3.33 subscapularis nerves (2-4). These different nerves split most often before entering subscapularis muscle; there were in average 5.05 entry points (3-6). Distances between entry points and clinical landmarks were as follows: cgs, 3.9-6.45 cm; cgi, 3.7-5.54 cm; tm, 5.9-7.15 cm; pc, 4.9-7.66 cm. Reporting these measurements onto a frame allowed to show that all these points were located in average medially to the scapular notch and at more than 3 cm from the anterior border of the glenoid cavity.

CONCLUSION

If the transverse division does not extend farther than 3 cm from the anterior border of the glenoid cavity and from the medial border of the root of the coracoid process, there should not be any injury of the subscapularis nerves.

Mini-open arthroscopically assisted Bristow-Latarjet procedure for the treatment of patients with anterior shoulder instability: a cadaver study

PURPOSE

The purpose of this study was to evaluate the arthroscopically assisted Bristow-Latarjet procedure. The aim was to use arthroscopic guidance to assist in positioning of the coracoid bone block onto the anterolateral aspect of the glenoid. The feasibility of this technique and its efficacy, reproducibility, and potential neurovascular complications were evaluated.

METHODS

A minimally invasive technique was used to harvest the coracoid bone block and the attached coracobiceps tendon. A portal was created through the subscapularis muscle and, under arthroscopic guidance, the anterior aspect of the glenoid was cleaned and reamed before the bone block was placed. Cannulated screws (3.5 mm) were used to fix the vertically oriented bone block to the glenoid. The size of the bone block, its position on the glenoid, and its relation to the subscapularis tendon and the musculocutaneous and axillary nerves were recorded.

RESULTS

In all 5 cadavers, the bone block was well positioned and was fixed to the anteroinferior part of the glenoid. No lesions of the cephalic vein or of the surrounding neurovasculature were observed.

CONCLUSIONS

This study demonstrated the safe and effective use of this arthroscopically assisted technique for correct positioning of the coracoid bone block at the anterolateral aspect of the glenoid in the cadaveric shoulder. Arthroscopy facilitated adequate reaming of the anterior glenoid and aided in optimal positioning of the bone block.

CLINICAL RELEVANCE

This cadaveric study highlights the advantages offered by an arthroscopically assisted Bristow-Latarjet procedure, which optimizes positioning of the block and ensures adequate reaming of the anterior glenoid, thereby potentially reducing the risks of early nonunion and late arthritis--complications commonly associated with the classical Bristow-Latarjet technique.

A prospective, randomized, clinical and radiographic study after arthroscopic Bankart reconstruction using 2 different types of absorbable tacks

PURPOSE

The aim of the study was to compare the clinical and radiographic results after arthroscopic Bankart reconstruction using 2 different types of absorbable implant.

TYPE OF STUDY

Randomized controlled trial.

METHODS

A randomized series of 40 patients who had recurrent, unidirectional, post-traumatic shoulder instability were included in the study. All patients underwent an arthroscopic Bankart reconstruction involving either polygluconate co-polymer (PGACP group, n = 20) or self-reinforced poly-L-lactic acid polymer (PLLA group, n = 20) tack implants. The patients underwent clinical and radiographic assessments preoperatively and at 2 years. Additional radiographic assessments were performed at 6 months.

RESULTS

Preoperatively, the study groups were comparable in terms of demographics as well as clinical parameters. One patient in each group had a redislocation (5%) during the follow-up period of 2 years. No subluxations were registered. No statistically significant differences were found between the study groups in terms of strength in abduction, range of motion, and Rowe or Constant scores. There was a significant increase in degenerative changes during the follow-up period in both study groups (P = .004). However, no significant differences in degenerative changes were registered between the study groups either preoperatively or at the 2-year follow-up. There were no significant differences in the radiographic visibility of the drill holes used for the absorbable implants between the study groups at the 6-month assessment. However, at the 2-year assessment, the radiographic visibility of the drill holes was significantly greater (P = .004) in the patients in the PLLA group than those in the PGACP group. At the 2-year assessment, no correlation was found between the appearance of the drill holes and the degenerative findings (PGACP group, rho = 0.44; PLLA group, rho = 0.42).

CONCLUSIONS

Two years after arthroscopic Bankart reconstruction using either PGA polymer or PLA polymer implants, the overall clinical results were comparable. Radiographic assessments revealed that the degenerative changes increased in both study groups during the follow-up period. Furthermore, the visibility of the drill holes on the 2-year radiographs was greater after using PLLA implants than after using PGACP implants.

LEVEL OF EVIDENCE

Level I.

Schwerwiegende Komplikation nach perkutan-transaxillärer Verschraubung einer Glenoidfraktur

The common treatment for glenoid rim fractures has been open reduction and internal fixation by a deltopectoral approach. Minimally invasive procedures with percutaneous transaxillary manipulation have a high risk for neurovascular damage. In a single case we demonstrate the possible complications associated with percutaneous refixation of a glenoid rim fracture. A 34-year-old patient with an anterior glenoid rim fracture was referred to our shoulder service after percutaneous transaxillary fixation of the fracture of the glenoid. He presented a dislocated fracture with joint infection and damage of the axillary nerve and artery. During revision surgery, joint infection with Staphylococcus aureus, dislocation of the fracture, aneurysm of the axillary artery, and a lesion in continuity of the axillary nerve were diagnosed. The fragment was excised and the capsule reattached to the remaining glenoid rim. The aneurysm was resected with an end-to-end anastomosis. The outcome was a noninfected and stable shoulder with a limited range of motion. In patients with a glenoid rim fracture with more then 21% of the glenoid fossa involved, refixation of the fracture is recommended. Open reduction and internal fixation is the gold standard. In some cases arthroscopic repair is possible. Percutaneous transaxillary manipulation is not recommended.

Morphometric study of the nerves entering into the coracobrachialis muscle

The nerves entering into the coracobrachialis muscle are the musculocutaneous nerve (MC) and the nerve (usually consists of several thin branches) branches to the coracobrachialis. These thin branches enter the coracobrachialis proximal to the MC. The thin branches and the MC are susceptible to injury during coracoid process transfer. The purpose of this study is (1) to reveal the number and origin of the thin branches and (2) especially to report the morphometric information about the two distances between the coracoid process and the points where the first thin branch and the MC enter the coracobrachialis. These distances were named as the "distance T1" and the "distance D," respectively. Forty-two cadaver upper extremities were used and the distance between the coracoid process and the medial epicondyle of the humerus as the "arm length" was measured. The "ratio T1" was calculated by dividing the distance T1 by the arm length. The "ratio D" was calculated by dividing the distance D by the arm length. The number of the thin branches varied between one and four. In the most common type, there were two thin branches (45%). All of the thin branches originated from the MC. The mean distance T1, distance D and arm length were found as 41.5, 62 and 304.5 mm, respectively. The mean ratio T1 and ratio D were determined as 0.13 (approximately 1/8) and 0.20 (=1/5), respectively. The findings about the number and origin of the thin branches may contribute to the anatomy of the nerve to the coracobrachialis. The shoulder surgeon may calculate the predicted distance T1 and distance D of any upper extremity, dividing its arm length by eight and five, respectively.

Arthroscopic versus open repair for traumatic anterior shoulder instability: a meta-analysis

PURPOSE

The purpose of this study was to critically evaluate the literature to determine whether open or arthroscopic surgical repair for traumatic recurrent anterior shoulder instability results in a better outcome.

TYPE OF STUDY

Meta-analysis.

METHODS

The search involved clinical studies in all languages in the MEDLINE database from 1966 to October 31, 2003. The following key words were used: (1) anterior shoulder instability, (2) Bankart lesion, (3) traumatic recurrent anterior shoulder instability, and (4) arthroscopic and open Bankart repair. All abstracts were reviewed and articles were included if there was a direct clinical comparison between arthroscopic and open repair for traumatic recurrent anterior shoulder instability. These articles were manually cross-referenced for additional abstracts. The final group of articles was independently critically appraised and the following outcomes were extracted: recurrent instability, return to activity, reoperation rate, and cause of recurrence.

RESULTS

The search terms resulted in 677, 183, 68, and 51 hits respectively. From these, 18 articles were determined to be eligible for full review including 2 foreign-language articles. Cross-referencing identified 2 unpublished studies. Eleven studies were included in the final analysis: 1 randomized trial, 2 pseudo-experimental designs, 4 prospective cohorts, 3 retrospective studies, and 1 case control study. Pooled Mantel-Haenszel odds ratio for recurrent instability and return to activity were 2.04 ( P = .003; 95% confidence interval, 1.27, 3.29) and 2.85 ( P = .004; 95% confidence interval, 1.40, 5.78), respectively, in favor of the open repair.

CONCLUSIONS

Based on this meta-analysis, open repair has a more favorable outcome with respect to recurrence and return to activity.

LEVEL OF EVIDENCE

Level III, Systematic Review of Level III (and II/I) Studies.

Arthroscopic repair of a humeral avulsion of the glenohumeral ligament lesion

We describe 3 cases of an all-arthroscopic technique for repair of a humeral avulsion of the glenohumeral ligament (HAGL) lesion and the postoperative clinical outcomes. From a technical perspective, the most critical part of the surgeries was the anchor insertion at an optimal position on the humerus in order to achieve proper tension of the glenohumeral ligament. The arm-free beach-chair position, which facilitates maximum internal rotation, use of a 70 degrees angled arthroscope, and an anterior-inferior trans-subscapularis tendon portal were considered key factors to accomplish this procedure.

Glenohumeral arthroscopy portals established using an outside-in technique: neurovascular anatomy at risk

PURPOSE

The purpose of this study was to examine the neurovascular structures at risk during placement of glenohumeral arthroscopy portals using an outside-in technique.

TYPE OF STUDY

Anatomic cadaveric study.

METHODS

Five fresh-frozen cadaveric specimens were used in this study. Each shoulder was mounted on a custom-designed apparatus allowing shoulder arthroscopy in a lateral decubitus position. The following portals were established using an outside-in technique and marked using an 18-gauge spinal needle: posterior, posterolateral, anterior, 5-o'clock, anterosuperolateral, and Port of Wilmington. Each specimen was carefully dissected after the procedure, and the distance from each portal site to the adjacent relevant neurovascular structures (axillary nerve, musculocutaneous nerve, lateral cord of the brachial plexus, cephalic vein, and axillary artery) was measured using a precision caliper.

RESULTS

Except for the cephalic vein, all of the neurovascular structures were more than 20 mm away from all the portals evaluated. When creating either an anterior portal or a 5-o'clock position portal, the mean distance from the portal to the cephalic vein was 18.8 mm and 9.8 mm, respectively. In one anterior portal, a direct injury to the cephalic vein occurred.

CONCLUSIONS

Our study suggests that shoulder arthroscopy portals placed in an outside-in fashion are unlikely to produce neurologic injury. However, the cephalic vein is at risk during placement of an anterior or 5-o'clock position portal, although probably with minimal subsequent patient morbidity. Placing portals in an outside-in fashion guarantees the correct angle of approach, with minimal risk to adjacent neurologic structures.

CLINICAL RELEVANCE

This study shows the safety of standard and accessory glenohumeral arthroscopy portals.

Temperature along the axillary nerve during radiofrequency-induced thermal capsular shrinkage

BACKGROUND

There have been reports of axillary nerve palsy after thermal capsular shrinkage with radiofrequency energy-generating devices. The exact cause of this is unknown.

HYPOTHESIS

The temperature of the axillary nerve increases during shoulder capsular shrinkage at various degrees of shoulder abduction.

STUDY DESIGN

Laboratory study.

METHODS

Fifteen cadaveric shoulders had fiberoptic thermometer probes placed at various points along the axillary nerve and major branches under the capsule. The shoulders underwent thermal capsular shrinkage with a radiofrequency energy-inducing device at various positions of abduction.

RESULTS

With the arm at the side, temperatures above 50 degrees C (56 degrees -61 degrees C) were evident along the teres minor branch of the axillary nerve in 4 of 6 specimens. The increase in temperature was noted in the middle to posterior aspect of the inferior capsule. At 45 degrees of abduction, 4 of 5 shoulders demonstrated increases in temperature greater or equal to 50 degrees. Three of 4 shoulders tested at 90 degrees of abduction revealed similar temperature increases.

CONCLUSIONS

The arthroscopic technique of thermal capsular shrinkage causes an increase in the temperature of the axillary nerve and its branches in 11 of 15 cadaveric specimens tested at various arm positions-particularly affected is the teres minor branch.

CLINICAL RELEVANCE

Orthopaedic surgeons using the radiofrequency device for thermal capsular shrinkage need to be aware of the possible increase in temperature along the axillary nerve and its branches during this procedure. The clinical effect of this type of increase on the nerve is unknown.

Differential arthroscopic portal placement for rotator cuff repair

We report an effective technique of arthroscopic portal placement for rotator cuff repair of the shoulder. The differential portals are placed depending on the location of the tear. After the glenohumeral arthroscopic examination, the subacromial bursoscopy is performed through the same posterior skin portal. With the rotator cuff tear in view, a spinal needle is inserted to the center of the tear, 3 cm from the lateral margin of the acromion (middle working portal). Another spinal needle is then inserted into the posterior lip of the tear, 1 cm from the lateral margin of the acromion (rear viewing portal). The rear viewing portal provides a good downward en-face view of the tear, and the middle working portal allows better access to the anterior and posterior margins of the cuff tear than the usual posterior and lateral portals do. This differential portal placement with respect to the location of the rotator cuff tear ensures superior access for arthroscopic repair of rotator cuff tears.

Comparison of open and arthroscopic stabilization for recurrent shoulder dislocation in patients with a Bankart lesion

We performed a prospective study of 117 patients (119 shoulders) with symptomatic, recurrent anterior posttraumatic shoulder instability to compare open versus arthroscopic reconstruction. Arthroscopic reconstructions (N = 66) were performed using bioabsorbable tacks (Suretac fixators), whereas open reconstructions (N = 53) were performed with suture anchors. All of the patients had a Bankart lesion. Independent observers examined 108 of the 119 shoulders (91%) at a median follow-up period of 28 months (range, 24 to 63) for the arthroscopic group and 36 months (range, 24 to 63) for the open group. The recurrence rate, including both dislocations and subluxations, was 9 of 60 (15%) in the arthroscopic group, compared with 5 of 48 (10%) in the open group. At follow-up, the Rowe score was 93 points (range, 39 to 100) and the Constant score was 91 points (range, 56 to 100) in the arthroscopic group, compared with 89 points (range, 53 to 100 and 57 to 100 for the Rowe and Constant scores, respectively) for both scores in the open group. The only significant difference was in external rotation in abduction, which was 90 degrees (range, 50 degrees to 135 degrees) in the arthroscopic group and 80 degrees (range, 25 degrees to 115 degrees) in the open group. Both methods produced stable and well-functioning shoulders in the majority of patients.

Arthroscopic visualization of the subscapularis tendon

PURPOSE

This study was conducted to define what portion of the subscapularis tendon is visualized during standard diagnostic glenohumeral arthroscopy and to determine the distance between the inferior aspect of the visible portion of the subscapularis tendon and the axillary nerve.

TYPE OF STUDY

Anatomic (cadaveric) analysis.

METHODS

Six fresh-frozen human cadaveric shoulders were placed in a simulated lateral decubitus position with longitudinal traction and 45 degrees of shoulder abduction. Glenohumeral arthroscopy was performed on each specimen using a standard posterior portal for visualization. The 4 corners of the visible portion of the subscapularis were tagged with arthroscopic sutures. The shoulders were subsequently dissected. The surface area defined by the 4 suture tags and the surface area of the entire subscapularis tendon were calculated for each specimen. The dimensions of these areas and the distance between the inferior aspect of the visible portion of the subscapularis tendon and the axillary nerve were measured with calipers.

RESULTS

The arthroscopically tagged portion of the subscapularis tendon represented only a small percentage (26% +/- 11%) of the entire tendon. The majority of the subscapularis tendon is veiled by the middle and inferior glenohumeral ligaments. There was a significant distance between the inferior aspect of the visible portion of the subscapularis tendon and the axillary nerve (32.8 +/- 6.0 mm). The mean height of the visible portion of the tendon represented 44% of the mean overall height of the subscapularis.

CONCLUSIONS

These data suggest that arthroscopic visualization of the subscapularis is incomplete. Lesions involving the concealed portion of the subscapularis tendon may not be detected arthroscopically. The wide margin of safety between the inferior aspect of the visible portion of the subscapularis tendon and the axillary nerve is relevant to the placement of anteroinferior (trans-subscapularis) arthroscopy portals as well as to performing arthroscopic anterior capsular releases.

Shoulder function after arthroscopic anterior stabilization of the glenohumeral joint using an absorbable tac

Among the advantages of arthroscopic stabilization could be less loss of range of motion and, with that, better functional outcome. In each of 24 shoulders, arthroscopic anterior repair of instability was performed through use of cannulated resorbable tacs (Suretacs), and the clinical outcome, especially the function, was examined in 20 shoulders after a mean follow-up of 3.4 years. The study included a retrospective analysis of 10 shoulders with documented recurrent anterior dislocations, 3 shoulders with posttraumatic subluxations, and 7 shoulders with painful apprehension and unequivocally clear Bankart lesions at arthroscopy. The evaluation of the recurrent dislocators revealed recurrence in 20%, residual instability in 10%, and a mean loss of external rotation of 28.5 degrees. No recurrence or residual instability was encountered in the other 2 groups. Mean loss of external rotation was 15 degrees in the group of subluxators and 20 degrees in the group of painful shoulders with intraoperatively evident instability. Through use of the Rowe score, failure was found in 30% of the dislocators; no failures were noted in the other groups. The painful shoulders with intraoperatively evident instability had significantly (P < .05) better Rowe scores than shoulders that had documented dislocation. Our series confirmed a relatively high failure rate for arthroscopic anterior stabilization of recurrent anterior dislocators. Our series did not confirm that arthroscopically successfully stabilized shoulders recover full function and mobility. In the light of the relatively high rate of residual instability and incomplete functional recovery in successfully stabilized shoulders, we have discontinued use of this technique for the treatment of recurrent dislocators.

Anatomy and biomechanics of the shoulder

The anatomies and biomechanics of the glenohumeral joint and the scapulothoracic articulation are the subjects of this article. The anatomies of bones, joints, ligaments, and muscles are described in detail, and current biomechanical concepts concerning motion, stability, and force are presented. Morphologic and biomechanical changes in pathologic conditions briefly are described.

Transfer of the pectoralis major muscle for the treatment of irreparable rupture of the subscapularis tendon

BACKGROUND

The clinical diagnosis of a tear of the subscapularis tendon is difficult, and the resulting delays frequently cause a major time-lapse before repair is attempted. Diagnostic delay often means that surgical repair is no longer possible. In twelve patients who had an irreparable tear of the subscapularis tendon, the superior one-half to two-thirds of the tendon of the pectoralis major muscle was used as a substitute for the subscapularis tendon. In order to adapt the orientation of the transferred muscle to that of the subscapularis, it was routed behind the conjoined tendon of the coracobrachialis muscle and the short head of the biceps to the lesser tuberosity.

METHODS

The operations were performed between May 1993 and June 1997. The average age of the twelve patients was sixty-five years old (range, forty-nine to eighty-one years old). Eight patients had an isolated rupture of the subscapularis tendon, and four had a concomitant lesion in the form of either a partial or a complete rupture of the supraspinatus tendon. The dominant symptoms were anterior shoulder pain and weakness that had responded poorly to nonoperative therapy. Four patients also had signs of recurrent anterior instability.

RESULTS

After an average follow-up interval of twenty-eight months (range, twenty-four to fifty-four months), nine of the twelve patients assessed the final result as excellent or good; three, as fair; and none, as poor. Pain was reduced, with the score improving from an average of 1.7 points (of a maximum of 15 points) preoperatively to an average of 9.6 points postoperatively. The patients' subjective functional evaluation improved from an average score of 20 points preoperatively to an average of 63 points postoperatively. The average functional rating with use of the Constant and Murley score increased from 26.9 to 67.1 percent of normal. All four preoperatively unstable shoulders were stable at the time of the latest follow-up.

CONCLUSIONS

This repair technique can be recommended as a reconstructive procedure for elderly patients who have an irreparable tear of the subscapularis tendon.

Bioabsorbable tacks for arthroscopic treatment of recurrent anterior shoulder dislocation

Seventy-eight patients (82 shoulders) with symptomatic, recurrent anterior post-traumatic shoulder instability and Bankart lesions were operated on with bioabsorbable tacks (Suretac fixators). All the patients were followed by an independent observer, with a median follow-up period of 27 (21-63) months. The recurrence rate was 8/82 (10%). The median Rowe score was 93 (37-100) points. The median Constant score for the index shoulders was 90 (34-100) points, compared with 93 (80-100) points for 59 non-operated healthy shoulders from the same cohort (P=0.03). The external rotation in abduction was 93 (50-135) degrees compared with 105 (75-145) degrees for the control shoulders (P=0.0018). Arthroscopic shoulder stabilization using bioabsorbable Suretac fixators appears to produce reliable results if used in patients with post-traumatic shoulder instability and a Bankart lesion.

Arthroscopic shoulder stabilization using transglenoid sutures

The results of arthroscopic stabilization using multiple transglenoid sutures in 24 patients with posttraumatic recurrent anterior shoulder instability are presented with a minimum follow-up of 2 years. No serious complications were recorded. There were 2 recurrences. The remaining 22 patients had good or excellent results according to the modified Rowe score, with a median score of 89. The median value for loss of external rotation was 5 degrees. Seventeen patients were active in sports and 11 returned to the same sports at the same competitive level.

Arthroscopic extra-articular Bankart repair for the treatment of recurrent anterior shoulder dislocation

This study describes a new arthroscopic procedure for the stabilization of recurrent anterior shoulder dislocations. The technique involves two important features. The first is the anterior inferior transmuscular approach through the subscapularis muscle, which permits self-locking implants to be inserted into the anterior inferior third of the glenoid rim so that they oppose the direction of pull of the capsule. This approach was studied on 79 cadaveric shoulders before clinical application. The second feature is the extracapsular (extra-articular) location of the self-locking implants, which permits a superomedial capsular shift as required. The technique offers a high degree of capsular stability. Of a total of 318 patients undergoing this procedure, the first 100 shoulders (98 patients) were evaluated postoperatively at an average of 35 months (range, 18 to 62 months). The diagnosis in all cases was traumatic recurrent anterior shoulder dislocation. Repair of the capsule was performed initially with screws and later with absorbable tacks. The overall recurrence rate was 9% (9 shoulders). Excluding the first 30 shoulders to take account of the learning curve, the recurrence rate for the subsequent 70 shoulders was only 5.7%. Limitation of external rotation at 0 degrees abduction averaged 6.7 degrees and 6.1 degrees at 90 degrees abduction for all shoulders; 61% of participants in overhead sports and 70% of participants in contact sports resumed their preinjury activities. The recurrence rate for patients involved in overhead sports was 10% and for collision sports it was 14%. There were no recurrences in the case of patients whose sports involve minimum risk to the shoulder (cycling, jogging). Most recurrences were observed in patients with lax shoulders and small Bankart lesions.