Arthroscopic treatment of acromioclavicular joint injuries and results

In Vivo Analysis of Acromioclavicular Kinematics and Distance During Multiplanar Humeral Elevation

BACKGROUND

Knowledge of acromioclavicular (AC) joint kinematics and distance may provide insight into the biomechanical function and development of new treatment methods. However, accurate data on in vivo AC kinematics and distance between the clavicle and acromion remain unknown.

PURPOSE/HYPOTHESIS

The purpose of this study was to investigate 3-dimensional AC kinematics and distance during arm elevation in abduction, scaption, and forward flexion in a healthy population. It was hypothesized that AC kinematics and distance would vary with the elevation angle and plane of the arm.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 19 shoulders of healthy participants were enrolled. AC kinematics and distance were investigated with a combined dual fluoroscopic imaging system and computed tomography. Rotation and translation of the AC joint were calculated. The AC distance was measured as the minimum distance between the medial border of the acromion and the articular surface of the distal clavicle (ASDC). The minimum distance point (MDP) ratio was defined as the length between the MDP and the posterior edge of the ASDC divided by the anterior-posterior length of the ASDC. AC kinematics and distance between different elevation planes and angles were compared.

RESULTS

Progressive internal rotation, upward rotation, and posterior tilt of the AC joint were observed in all elevation planes. The scapula rotated more upward relative to the clavicle in abduction than in scaption (P = .002) and flexion (P = .005). The arm elevation angle significantly affected translation of the AC joint. The acromion translated more laterally and more posteriorly in scaption than in abduction (P < .001). The AC distance decreased from the initial position to 75° in all planes and was significantly greater in flexion (P < .001). The MDP ratio significantly increased with the elevation angle (P < .001).

CONCLUSION

Progressive rotation and significant translation of the AC joint were observed in different elevation planes. The AC distance decreased with the elevation angle from the initial position to 75°. The minimum distance between the ASDC and the medial border of the acromion moved anteriorly as the shoulder elevation angle increased.

CLINICAL RELEVANCE

These results could serve as benchmark data for future studies aiming to improve the surgical treatment of AC joint abnormalities to restore optimal function.

Morphology of the acromioclavicular-joint score (MAC)

INTRODUCTION

To date there is no generally accepted specific definition or classification of acromioclavicular (AC) joint osteoarthritis. The aim of this study is to analyze morphological parameters using magnetic resonance imaging (MRI) and to develop a scoring system as a basis for decision making to perform an AC-joint resection.

MATERIALS AND METHODS

In a retrospective-monocentric matched pair study, healthy and affected subjects were investigated using T2 MRI scans in the transverse plane. There were two groups, group 1 (n = 151) included healthy asymptomatic adults with no history of trauma. In group 2, we included n = 99 patients with symptomatic AC joints, who underwent arthroscopic AC-joint resection. The central and posterior joint space width and the AC angle were measured. Morphological changes such as cartilage degeneration, cysts and bone edema were noted. Malalignment of the joint was defined as: posterior joint space width < 2 mm in conjunction with an AC angle > 12°. A scoring system consisting of the measured morphologic factors was developed.

RESULTS

Symptomatic and asymptomatic patients showed significant differences in all measured items. We observed a significant difference in the MAC score for symptomatic and asymptomatic patients (mean 10.4 vs. 20.6, p = 0.0001). The ROC (receiver operator characteristic) analysis showed an excellent AUC of 0.899 (p = 0.001). The sensitivity of the MAC score was 0.81 and the specificity 0.86. The MAC score shows a significant moderate correlation with age (r = 0.358; p = 0.001). The correlation of age and the development of symptoms was only weak (r = 0.22, p = 0.001). Symptomatic patients showed significantly more frequent malalignment compared to asymptomatic patients (p = 0.001), but the positive predictive value that a patient with malalignment is also symptomatic is only 55%.

CONCLUSION

Patients with symptomatic AC joints showed a typical pattern of morphological changes on axial MRI scans with early posterior contact of the joint surfaces, reduction of joint space and malalignment as the basis for the development of a scoring system. The MAC score shows excellent test characteristics, and therefore, proved to be both an appropriate guidance for clinical practice as well as an excellent tool for comparative studies and is superior to the assessment of malalignment alone.

LEVEL OF EVIDENCE

Level IV, retrospective diagnostic study.

Detailed management of post-traumatic distal clavicle osteolysis in a 24-year-old female: a case report

INTRODUCTION

Distal clavicular osteolysis (DCO) is a musculoskeletal pathology characterized by shoulder pain. Given the high prevalence of shoulder pain due to rotator cuff and subacromial injuries, DCO is often overlooked. Conservative therapy is indicated prior to surgical intervention. However, no literature has described conservative management of DCO in detail. This report will outline conservative management details for DCO to guide future research and clinicians.

CASE PRESENTATION

A 24-year-old female hockey player presented with trauma-induced injury, where she was diagnosed with type II acromio-clavicular joint separation. She presented 5-months later with residual pain and limitations in ranges of motion (ROM). Radiographic images revealed DCO.

MANAGEMENT AND OUTCOME

Management entailed strict rest from overhead activities followed by rehabilitation and manual therapy. 6-months later the patient reported resolution of symptoms, improved ROMs, and activities of daily living.

SUMMARY

DCO can be difficult to diagnose given its limited etiological understanding, low incidence, and poor radiographic sensitivity. DCO diagnosis should be considered in cases with unresolving shoulder pain.

Percutaneous distal clavicle excision for acromioclavicular joint arthritis: our experience and early results of a novel surgical technique

PURPOSE

Symptomatic acromioclavicular joint (ACJ) osteoarthritis causes pain and limitations in activities of daily living. Open and arthroscopic distal clavicle excision techniques have been described with good outcomes. However, both techniques have their own sets of advantages and disadvantages. This study describes a novel technique of percutaneous distal clavicle excision for symptomatic ACJ osteoarthritis and our two-year results.

METHODS

Fifteen consecutive patients underwent percutaneous distal clavicle excision for ACJ arthritis. These patients had failed a trial of conservative treatment. The ACJ was confirmed as the pain generator with an intraarticular steroid/lignocaine injection, and shoulder MRI was used to exclude alternative pain generators in the shoulder. They had a minimum of two years of follow-up.

RESULTS

At a mean of 26.8 months postoperatively, the mean VAS pain score was 0, and the mean Constant score for the shoulder was 87.3 points (range 50-94), which corresponded to 1 good, 1 very good and 13 excellent results. The mean SF-36 score was 94.9 points (range 65-100). There were statistically significant improvements in the VAS scores, Constant shoulder scores and SF-36 scores at one year and two years of follow-up (p < 0.05). Three unique complications, namely subcutaneous emphysema, "missing" of the distal clavicle and thermal skin injury, were encountered. Our surgical technique has since been modified to circumvent these complications.

CONCLUSION

Our novel technique of percutaneous distal clavicle excision yields a 93.3% good-to-excellent results based on the Constant shoulder score and durable pain relief based on VAS at two years.

Histologic and magnetic resonance image evaluation in acromioclavicular joint osteoarthritis

Introduction

Little is known about the development of specific acromioclavicular joint osteoarthritis. Its histologic alterations are controversial, and radiologic alterations are seen in asymptomatic people. The objective of this study was to evaluate histologically the distal clavicle subchondral bone and to analyze magnetic resonance images in patients with painful and nonpainful acromioclavicular joint osteoarthritis.

Methods

An observational, analytical, and cross-sectional study with a control group was conducted. Between August 2018 and June 2019, we analyzed a total of 41 patients. Group 1 consisted of patients with pain in the acromioclavicular joint (symptomatic osteoarthritis), and group 2 consisted of patients without pain in the acromioclavicular joint (asymptomatic osteoarthritis).

Results

Twelve of the 15 patients with acromioclavicular joint pain (group 1) were female, 13 presented distal clavicle edema on magnetic resonance imaging, and 9 had subchondral bone edema on histologic examination. Patients with acromioclavicular joint pain had longer shoulder pain duration than patients without pain. Women were more likely to have acromioclavicular joint pain compared with men. Patients with edema on magnetic resonance imaging showed a greater chance of presenting pain in the acromioclavicular joint in comparison with patients without edema.

Conclusion

Women had a higher chance of presenting with acromioclavicular joint pain than men. Patients with edema on magnetic resonance imaging were more likely to present with pain than patients without edema. Patients with acromioclavicular joint pain had longer shoulder pain duration than patients without pain, and subchondral bone edema on histologic examination was more frequent in patients with pain.

Does Distal Clavicle Resection Decrease Pain or Improve Shoulder Function in Patients With Acromioclavicular Joint Arthritis and Rotator Cuff Tears? A Meta-analysis

BACKGROUND

Acromioclavicular joint arthritis is a common, painful, and often missed diagnosis, and it often accompanies other shoulder conditions such as rotator cuff disease. Whether distal clavicle resection is important to perform in patients undergoing surgery for rotator cuff tears and concomitant acromioclavicular joint arthritis is controversial.

QUESTIONS/PURPOSES

The purpose of this study was to perform a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the effect of distal clavicle resection on (1) outcome scores; (2) shoulder ROM, joint pain or tenderness, and joint instability; and (3) risk of reoperation among patients treated surgically for rotator cuff tears who had concomitant acromioclavicular joint arthritis.

METHODS

We systematically searched the PubMed, EMBASE, and Cochrane databases to find RCTs that met our eligibility criteria, which, in summary, (1) compared rotator cuff repair plus distal clavicle resection with isolated rotator cuff repair for patients who sustained a full- or partial-thickness rotator cuff tear and concomitant acromioclavicular joint arthritis; and (2) the followup period was at least 2 years. Two reviewers screened the studies, extracted the data and evaluated the methodological quality, and performed data analysis. Statistical heterogeneity among studies was quantitatively evaluated with the I index. No heterogeneity was detected (I = 0%; p = 0.75) in terms of acromioclavicular joint pain or tenderness, Constant score, forward flexion, external rotation, and risk of reoperation, so fixed-effect models were used in these endpoints. Heterogeneity was moderate for the American Shoulder and Elbow Surgeons (ASES) score (I = 53%; p = 0.12) and low for the visual analog scale (VAS) score (I = 35%; p = 0.22), so random-effect models were used in these endpoints. Subgroup analysis was stratified by the symptom of acromioclavicular joint arthritis. Three RCTs with 208 patients were included. We evaluated the risk of bias using the Cochrane risk-of-bias tool; in aggregate, the three RCTs included showed low to intermediate risk, although not all parameters of the Cochrane tool could be assessed for all studies.

RESULTS

There was no difference between the distal clavicle resection plus rotator cuff repair group and the isolated rotator cuff repair group in ASES score (mean difference =1.41; 95% confidence interval [CI], -3.37 to 6.18; p = 0.56) nor in terms of the VAS score and Constant score. Likewise, we found no difference in ROM of the shoulder (forward flexion, internal rotation, and external rotation) or acromioclavicular joint pain or tenderness between the groups (pooled results of acromioclavicular joint pain or tenderness: risk ratio [RR], 1.59; 95% CI, 0.67-3.78; p = 0.30). Acromioclavicular joint instability was only detected in the rotator cuff repair plus distal clavicle resection group. Finally, we found no difference in the proportion of patients undergoing repeat surgery between the study groups (pooled results of risk of reoperation for the rotator cuff repair plus distal clavicle resection and isolated rotator cuff repair: one of 52 versus two of 78; RR, 0.86; 95% CI, 0.11-6.48; p = 0.88).

CONCLUSIONS

Distal clavicle resection in patients with rotator cuff tears did not result in better clinical outcome scores or shoulder ROM and was not associated with a lower risk of reoperation. Distal clavicle resection might cause acromioclavicular joint instability in patients with rotator cuff tears and concomitant asymptomatic acromioclavicular joint arthritis. Arthroscopic distal clavicle resection is not recommended in patients with rotator cuff tears and concomitant acromioclavicular joint arthritis. Additional well-designed RCTs with more participants, long-term followup, and data on patient-reported outcomes are needed.

LEVEL OF EVIDENCE

Level I, therapeutic study.

A combined technique for acromioclavicular reconstruction after acute dislocation - technical description and functional outcomes

Objective

This study aims to describe the surgical approach to such injuries and to present the clinical and functional outcomes obtained in a cohort of patients.

Methods

This is an observational retrospective study that included 153 patients with acute acromioclavicular joint dislocation, operated between 1999 and 2015. Clinical evaluation included the following outcomes: Constant functional scale, development of complications, time to return to previous work/sport activities, and satisfaction index. The contra-lateral (uninjured) shoulder was used as control in subjective outcomes. Radiological evaluation was performed in order to monitor signs of loss of reduction, degenerative joint changes, and coracoclavicular calcifications.

Results

The mean age was 29.20 ± 9.53 (16–71), with a large male predominance (91.5%). Follow-up lasted 55.41 ± 24.87 (12–108) months. The mean Constant score attained was 96.45 ± 4.00 (84–100) on operated shoulders and 98.28 ± 1.81 (93–100) on contralateral ones. Almost all patients (98.69%) were satisfied with the surgical results. Worse outcomes were observed in acromioclavicular joint dislocations of increasing grade (from type III to V, but worse for type IV), both concerning the Constant score and return to work or sport. The overall incidence of complications was considered low, with the most prevalent being Kirschner wire failure and isolated coracoclavicular ligament calcifications.

Conclusion

The surgical technique described is an excellent option in the treatment of acute acromioclavicular joint dislocations of Rockwood grades III to V. This is corroborated by the excellent clinical and functional outcomes and the low rate of complications.

Diagnosis and Management of Distal Clavicle Osteolysis

Distal clavicle osteolysis is an uncommon condition that most commonly affects weight lifters and other athletes who perform repetitive overhead activity. Although this condition most commonly presents in young active men, it is becoming increasing more common in women with the rise in popularity of body building and extreme athletics. Distal clavicle osteolysis can be debilitating, especially in those with rigorous training regimens, preventing exercise because of pain with activities such as bench presses and chest flies. Aside from a careful history and physical examination, radiographic evaluation is essential in distinguishing isolated distal clavicle osteolysis from acromioclavicular joint pathology, despite a potentially similar presentation of the 2 conditions. Nonoperative therapy that includes activity modification, nonsteroidal anti-inflammatory drugs, and cortisone injections is the first-line management for this condition. Patients whose conditions are refractory to nonoperative modalities may benefit from distal clavicle resection via either open or arthroscopic techniques. Arthroscopic techniques typically are favored because of improved cosmesis and the added benefit of the ability to assess the glenohumeral joint during surgery to rule out concomitant pathology. There are varying operative techniques even within arthroscopic management, with pros and cons of a direct and an indirect surgical approach. Patients often do well after such procedures and are able to return to their preinjury level of participation in a relatively short period. [Orthopedics. 2017; 40(2):119-124.].

Limited distal clavicle excision of acromioclavicular joint osteoarthritis

INTRODUCTION

Resection of the distal aspect of clavicle has a well-documented treatment modality in case of acromioclavicular joint osteoarthritis resistant to conservative treatment.

HYPOTHESIS

Limited (mean ∼0.5cm distal end of clavicle resection) distal clavicle excision of A-C joint arthritis in cases resistant to conservative treatment may reduce the pain and improve the shoulder function.

MATERIAL AND METHODS

In this study, we retrospectively evaluated the results of limited distal clavicle excision of acromioclavicular joint osteoarthritis resistant to conservative treatment. All patients were evaluated by using the Visual Analogue Scale (VAS) and UCLA shoulder rating scale (University of California Los Angeles), either before surgery or final follow-up period for pain and functional results, respectively.

RESULTS

A total of 110 patients (48 male, 62 female) with AC joint arthritis, treated between the years of 2008-2012, were retrospectively analyzed. A total of 30 patients (12 male, 18 female) who failed to show improvement with conservative treatment underwent limited surgical open excision of distal clavicle. The mean age of the study population was 52.5±1.2 years. The mean follow-up period was 27±1.3 months. The mean preoperative VAS score was 83.6±5.58 (range, 70-90) while mean VAS was 26.6±9.3 (range, 10-50) at the final follow-up. There was a statistically significant difference between pre- and postoperative VAS scores in patients who had treated by surgical approach (P<0.001). The mean UCLA score of the patients increased postoperatively from 11.5 (range, 9-14) to 29.2 (range, 27-32) at the final follow-up. There was a statistically significant difference between the two time periods with respect to UCLA scores (P<0.001).

DISCUSSION AND CONCLUSION

In patients with AC osteoarthritis resistant to conservative therapy, the hypothesized limited clavicle excision (mean ∼0.5cm distal end of clavicle resection with preserving coracoclavicular ligaments and inferior capsule) reduced the pain and improved the shoulder function.

CONCLUSION

Our midterm follow-up (mean 27 months) results showed that limited distal clavicle excision of patients with AC joint osteoarthritis resistant to conservative treatment (0.5cm distal end of clavicle resection with preserving inferior capsule, and coracoclavicular ligaments) reduced the pain and improved the shoulder function.

LEVEL OF EVIDENCE

IV (Retrospective study).

Coronal plane radiographic evaluation of the single TightRope technique in the treatment of acute acromioclavicular joint injury

BACKGROUND

This study aimed to demonstrate the technical aspects of the single TightRope (Arthrex, Naples, FL, USA) procedure for acute acromioclavicular-coracoclavicular joint dislocation, identify the predictive factors influencing its outcome, and assess and validate the significance of specific radiologic parameters.

METHODS

We reviewed true anteroposterior shoulder radiographs of 62 consecutive patients who had undergone surgical reconstruction using TightRope for an acute acromioclavicular-coracoclavicular injury. All patients were followed up for at least 12 months between October 2009 and March 2012 and were divided into dissociated or nondissociated groups according to their surgical outcome. We measured the clavicle tunnel anteroposterior angle, distal clavicular tunnel placement, and tunnel-to-medial coracoid ratio, and compared the parameters in each group after a satisfactory intraclass correlation coefficient reliability test result.

RESULTS

The angles of patients in the dissociated group were more acute compared with the angles of those in the nondissociated group, which were perpendicular, as verified statistically using the paired t test. The difference in the distal clavicular tunnel placement and tunnel-to-medial coracoid ratio between the groups was not significant. Therefore, tunnel placement is not influenced by coracoclavicular dissociation.

CONCLUSIONS

The clavicle tunnel anteroposterior angle can be used as a predictor of surgical outcome in coracoclavicular augmentation surgery. The surgeon should strive to place a perpendicular hole from the clavicle to the coracoid process for the TightRope fixation to enable a successful reconstruction of the acute acromioclavicular-coracoclavicular injury.

Surgical treatment for acromioclavicular joint osteoarthritis: patient selection, surgical options, complications, and outcome

Osteoarthritis is one of the most common causes of pain originating from the acromioclavicular (AC) joint. An awareness of appropriate diagnostic techniques is necessary in order to localize clinical symptoms to the AC joint. Initial treatments for AC joint osteoarthritis, which include non-steroidal anti-inflammatory drugs (NSAIDS) and corticosteroids, are recommended prior to surgical interventions. Distal clavicle excision, the main surgical treatment option, can be performed by various surgical approaches, such as open procedures, direct arthroscopic, and indirect arthroscopic techniques. When choosing the best surgical option, factors such as avoidance of AC ligament damage, clavicular instability, and post-operative pain must be considered. This article examines patient selection, complications, and outcomes of surgical treatment options for AC joint osteoarthritis.

Failure of coracoclavicular artificial graft reconstructions from repetitive rotation

PURPOSE

To assess how suture type and suture construct in an augmented Weaver-Dunn reconstruction affect coracoclavicular sling failure and rotary stability.

METHODS

Fifteen cadaveric shoulders were tested in rotation about the long axis of the clavicle with 10 lb of simulated arm weight. The clavicle was rotated 50 degrees about its long axis, and the applied torque was recorded. Next, modified Weaver-Dunn reconstruction was conducted. Two types of coracoclavicular sling (opposed drill holes through the clavicle and complete loop around the clavicle) were tested by use of 3 different sutures (FiberWire [Arthrex, Naples, FL], Mersilene tape [Ethicon, Somerville, NJ], and braided polydioxanone [PDS] [Ethicon]). For each sling-suture combination, the joint was retested over 50 degrees of rotation and then cycled over 40 degrees of rotation for 15,000 cycles or until failure.

RESULTS

After modified Weaver-Dunn reconstruction with either sling construct, mean torque over 50 degrees of acromioclavicular rotation was significantly reduced in posterior (P < .0001) and anterior (P < .0001) rotation, with any suture material tested. When the coracoclavicular sling was placed through opposed drill holes, no wear to the bone or suture was observed. When the sling material was looped around the clavicle, FiberWire and PDS resulted in abrasion of soft tissue and periosteum. In all cases sawing motion between bone and suture was observed at the coracoid. The FiberWire itself failed at a mean of 8,213 cycles. Some wear was noted in the Mersilene tape. PDS suture showed no wear.

CONCLUSIONS

In a cadaveric model of modified Weaver-Dunn reconstruction, a coracoclavicular suture loop was used to augment coracoacromial ligament transfer. Suture loops secured around the entire clavicle were shown to contribute to increased abrasive wear. Securing suture loops through opposed drill holes in the clavicle resulted in decreased abrasive wear.

CLINICAL RELEVANCE

Proper selection of suture type and suture construct may affect the failure rate of augmented Weaver-Dunn reconstructions.

Acromioclavicular joint problems in athletes and new methods of management

The acromioclavicular (AC) complex consists of bony and ligamentous structures that stabilize the upper extremity through the scapula to the axial skeleton. The AC joint pathology in the athlete is generally caused by 1 of 3 processes: trauma (fracture, AC joint separation, or dislocation); AC joint arthrosis (posttraumatic or idiopathic); or distal clavicle osteolysis. This article presents systematically the relevant anatomy, classification, evaluation, and treatment of these disorders. Management of AC joint problems is dictated by the severity and chronicity of the injury, and the patient's needs and expectations.

Acromioclavicular joint injuries: diagnosis and management

Acromioclavicular joint injuries represent nearly half of all athletic shoulder injuries, often resulting from a fall onto the tip of the shoulder with the arm in adduction. Stability of this joint depends on the integrity of the acromioclavicular ligaments and capsule as well as the coracoclavicular ligaments and the trapezius and deltoid muscles. Along with clinical examination for tenderness and instability, radiographic examination is critical in the evaluation of acromioclavicular joint injuries. Nonsurgical treatment is indicated for type I and II injuries; surgery is almost always recommended for type IV, V, and VI injuries. Management of type III injuries remains controversial, with nonsurgical treatment favored in most instances and reconstruction of the acromioclavicular joint reserved for symptomatic instability. Recommended techniques for stabilization in cases of acute and late symptomatic instability include screw fixation of the coracoid process to the clavicle, coracoacromial ligament transfer, and coracoclavicular ligament reconstruction. Biomechanical studies have demonstrated that anatomic acromioclavicular joint reconstruction is the most effective treatment for persistent instability.

Injuries to the acromioclavicular joint

Injuries to the acromioclavicular joint are common but underdiagnosed. Sprains and minor subluxations are best managed conservatively, but there is debate concerning the treatment of complete dislocations and the more complex combined injuries in which other elements of the shoulder girdle are damaged. Confusion has been caused by existing systems for classification of these injuries, the plethora of available operative techniques and the lack of well-designed clinical trials comparing alternative methods of management. Recent advances in arthroscopic surgery have produced an even greater variety of surgical options for which, as yet, there are no objective data on outcome of high quality. We review the current concepts of the treatment of these injuries.

Vascular anatomy of the subacromial space: a map of bleeding points for the arthroscopic surgeon

PURPOSE

Our purpose was to study the vascular anatomy of the subacromial space and to map the major sources of expected bleeding during subacromial arthroscopy surgery.

METHODS

Ten shoulders of five adult cadavers underwent whole-body arterial perfusion with a mixture of lead oxide, gelatin, and water. The tissue specimens were dissected, photographed, radiographed, scanned, and analyzed with a digital software analyzer. Dissection of the arteries of the subacromial space, with their respective anatomic landmarks, was documented. Correlations of bleeding areas during subacromial arthroscopic surgery and cadaveric dissection were carried out. A vascular map of the walls of the subacromial space was created.

RESULTS

The vascularity of the subacromial structures showed consistent patterns of distribution in 60% of the shoulders dissected, and specific sources of bleeding were analyzed. We divided this space into walls with their major arteries as follows: anterior wall, with the acromial branch of the thoracoacromial artery; posterior wall, with the posteromedial acromial branch of the suprascapular artery; and medial wall, with the anterior and posterior arteries of the acromioclavicular joint. The vascular map of the lateral wall, roof, and floor of the subacromial space was also described.

CONCLUSIONS

Vascular maps of the arteries of the walls of the subacromial space were created. The subacromial space is highly vascular, and the pattern of blood supply was found to be constant in 60% of the shoulders dissected. This knowledge of the vascular anatomy may decrease bleeding during surgery.

CLINICAL RELEVANCE

Knowledge of the vascular anatomy may decrease vascular damage during subacromial arthroscopy surgery.

Evaluation and treatment of acromioclavicular joint injuries

Acromioclavicular joint injuries and, more specifically, separations are commonplace both in general practice and during athletic participation. This article reviews the traditional classification as well as the clinical evaluation of patients with acute and chronic acromioclavicular joint separations. It also highlights many recent advances, principally in the anatomy and biomechanics of the acromioclavicular joint ligamentous complex. The concept of increases in superior translation as well as disturbances in horizontal translation with injuries to this joint and ligaments are discussed. This information, coupled with the unpredictable long-term results with the Weaver-Dunn procedure and its modifications, have prompted many recent biomechanical studies evaluating potential improvements in the surgical management of acute and chronic injuries. The authors present these recent works investigating cyclic loading and ultimate failure of traditional reconstructions, augmentations, use of free graft, and the more recent anatomic reconstruction of the conoid and trapezoid ligaments. The clinical results (largely retrospective), including acromioclavicular joint repair, reconstruction and augmentation with the coracoclavicular ligament, supplemental sutures, and the use of free autogenous grafts, are summarized. Finally, complications and the concept of the failed distal clavicle resection and reconstruction are addressed. The intent is to provide a current, in-depth treatise on all aspects of acromioclavicular joint complex injuries to include anatomy, biomechanics, benchmark studies on instability and reconstruction, clinical and radiographic evaluation, and to present the most recent clinical research on surgical outcomes.

Arthroscopic distal clavicle resection: a comparison of bursal and direct approaches

PURPOSE

To test the hypothesis that the direct (superior) approach to arthroscopic distal clavicle resection is as safe and effective as the bursal (subacromial) approach.

METHODS

All patients who had an arthroscopic distal clavicle resection in our institution between 1994 and 2002 were reviewed. Patients with a history of acromioclavicular joint (ACJ) instability, previous shoulder surgery, glenohumeral pathology, full-thickness rotator cuff tear, or other significant orthopaedic comorbidity were excluded. Outcome data were collected including the American Shoulder and Elbow Surgeons (ASES) score as well as subjective ratings of pain and instability.

RESULTS

Follow-up was completed on 66 shoulders of 60 patients. Twenty-four shoulders had a bursal approach (group I) and 42 had a direct approach (group II). There were 45 men and 15 women with an average age of 46 years (range, 21 to 78 years). Follow-up averaged 6.0 years (range, 2 to 11.5 years). The average ASES score was 90 (range, 53-100) in group I and 94 (range, 55-100) in group II. Four patients (10%) in group II required reoperation: 2 patients required ACJ stabilization at 6 and 9 months postoperatively because of anteroposterior instability, and 2 patients required resection again at 5 years because of recurrent symptoms.

CONCLUSIONS

Both the direct and bursal approaches lead to satisfactory outcomes in the majority of patients with ACJ arthrosis. However, the direct approach to the ACJ may damage the superior capsular ligaments, potentially leading to distal clavicle instability. Care should be taken when performing the direct ACJ resection to avoid disrupting the capsular restraints.

LEVEL OF EVIDENCE

Level IV therapeutic case series.