The relation of the coracoclavicular ligament insertion to the acromioclavicular jointA cadaver study of relevance to lateral clavicle resection

Medial placement of trapezoid tunnel leads to higher reduction loss in acute acromioclavicular joint dislocation treated with anatomic coracoclavicular fixation

Aim

To analyze the association between clavicular tunnel positioning and postoperative reduction loss in patients with acute acromioclavicular (AC) joint dislocation treated with anatomic coracoclavicular (CC) fixation using double clavicular tunnels.

Methods

A retrospective review of patients with AC joint dislocation, treated with anatomic CC fixation using double clavicular tunnels, was conducted. Patients with pre-operative, immediate post-operative, and final follow-up Zanca-view X-rays were included. On each X-ray, the obtained measures included: distance from lateral border of clavicle to trapezoid and conoid tunnels, distance between tunnels, clavicle length, and CC distance of affected and un-affected sides. Loss of reduction was calculated as CC distance difference between immediate and final post-operative X-rays. Association between reduction loss and tunnel positioning was analyzed.

Results

Conoid, trapezoid and tunnel ratios were 24% ± 4, 15% ± 3, and 9% ± 2, respectively. Significant reduction loss was seen in 21(45.7%) patients. Significantly higher probabilities of reduction loss were associated with trapezoid tunnels placed medial to 24 mm (30.8% vs 65.0%, OR 4.2 (IC95%: 1.2-14.4), p: 0.024) or 15% of the clavicle length (32.1% vs 66.7%, OR 4.2 (IC 95%: 1.2-14.9), p: 0.025).

Conclusions

Trapezoid tunnels placed medial to 24 mm or 15% medial to clavicle length could lead to higher probabilities of significant reduction loss. These findings support the importance of clavicular tunnels' proper placement for decreasing significant reduction loss.

Iatrogenic Excessive Clavicle Resection as a Complication of Arthroscopic Distal Clavicle Excision

Arthroscopic distal clavicle excision (DCE) is a reliable procedure to treat acromioclavicular joint arthritis. Typically, only 1 to 2 cm of distal clavicle should be removed. Resection of too much bone can lead to instability of the joint or lack of support to the shoulder. We describe 2 patients who had excessive clavicular bone removed arthroscopically, leading to irreparable clavicular pain and dysfunction. The 2 female patients, ages 56 and 60 years, presented to our clinic with continued pain after DCE. Both had pain intractable with nonoperative treatment and loss of range of motion of the shoulder. Radiographs revealed a distal clavicle defect of 7.5 cm in 1 patient. The second patient had a 2-cm distal clavicular defect with an adjacent 2-cm clavicle bone fragment between the defect and residual clavicle shaft. Both underwent surgery with subtotal claviculectomy for pain control. During surgery, 1 patient had a subclavian vein requiring vascular repair. After 1 year of follow-up, both patients had reduced but residual pain and restricted range of motion. Only 1 patient could rejoin her preinjury occupation. Neither patient could continue with preinjury recreational sports. Excessive removal of the distal clavicle during DCE can result in continued pain and disability of the shoulder. Methods to visualize the anatomy of the distal clavicle and its articulation to the acromion should be considered when performing this operation arthroscopically. Reoperation to remove subtotal clavicle has good clinical outcomes but may lead to serious complications due to the proximity to major neurovascular structures. [Orthopedics. 2024;47(1):e57-e60.].

Reversed total shoulder arthroplasty after acromioclavicular joint resection yields equivalent clinical results compared to a matched control group

INTRODUCTION

Reverse total shoulder arthroplasty (RTSA) is a well-establish procedure with increasing incidence. Depending on the medical history, many patients undergo multiple soft-tissue procedures before RTSA. The role of acromioclavicular pathology as well as the consequences of a distal clavicle resection (DCR) before RTSA has not been evaluated yet.

MATERIAL AND METHODS

A retrospective single-center review was performed on all patients undergoing primary RTSA with or without DCR with a minimum follow-up of 2 years. We compared patient-reported outcome measures (Constant score (CS), subjective shoulder values (SSV), and range of motion (ROM)) with a matched control group. The control group consisted of patients treated with a RTSA without DCR and matching was performed for age, sex, operating side, American Society of Anesthesiologists (ASA), body mass index (BMI), and indication. Surgical time and complication rate were recorded.

RESULTS

Thirty-nine patients with a mean follow-up of 63 months (SD 33) were enrolled in the study group. Mean age was 67 years (SD 7) with 44% male patients for both groups. The mean relative CS improved from 43% (SD 17) to 73% (SD 20) in the study group, and from 43% (18) to 73% (22) in the control group. The SSV improved from 29% (SD 17) to 63% (SD 29) in the study group, and from 28% (SD 16) to 69% (SD 26) in the control group (both n.s.). The postoperative ROM did not significantly differ between the two groups. Five patients in the study group and six in the control group had reoperations.

CONCLUSION

Patients who received a DCR before RTSA showed equivalent clinical outcomes compared to a match-control group with RTSA only. Surgical time was not different, and no complication related to the open DCR was observed in the study group. Therefore, we conclude that a prior DCR does not influence the postoperative outcome after RTSA.

LEVEL OF EVIDENCE

Level III: Retrospective comparative study.

Management of Acromioclavicular Joint Injuries: A Historic Account

There has been a rapid evolution in best practice management of acromioclavicular (AC) joint injuries. AP, Zanca, scapular Y, and dynamic axillary radiographic views provide optimal visualization of the joint and may assess for the presence of horizontal AC instability. Severity of AC joint pathology is classified according to the 6-tier Rockwood scoring system. Over 160 surgical techniques have been described for AC joint repair and reconstruction in the last decade; as a result, determining the optimal treatment algorithm has become increasingly challenging secondary to the lack of consistently excellent clinical outcomes.

Bony Regrowth and New Spur Formation as Possible Causes of Failed Distal Clavicle Excision-Mid-Term Outcomes after Revision Surgery in a Matched-Pair Analysis

BACKGROUND

Despite high rates of successful outcomes after open and arthroscopic distal clavicle excision (DCE) for symptomatic acromioclavicular joint (ACJ) degeneration, some patients present with persistent symptoms and disabilities after surgical intervention. This study aims to compare radiological, functional, and subjective outcomes of open revision surgery after failed arthroscopic DCE to primary successful arthroscopic DCE.

METHODS

In this retrospective case-control study, 10 patients who underwent open DCE revision were age- and gender-matched with 10 patients who did not require revision surgery after DCE. Radiographic evaluation included presence of acromioclavicular spurs and acromioclavicular joint distance. Functional and subjective outcomes were assessed using the CS, SSV, SST, VAS for pain, patient's satisfaction, ASES and quick DASH score.

RESULTS

At the latest postoperative follow-up (case: 57.3 ± 19.2 months; control: 63.5 ± 16.3 months), spur formation was detected in twice as many cases in the revision group, while acromioclavicular distance showed no significant difference. However, a significant bony regrowth was noticed in the revision group between revision surgery and latest follow-up, with a decrease of the acromioclavicular distance from 9.2 ± 1.6 mm to 5.9 ± 4.6 mm (p = 0.026) and a development of new spur formations in 30% of cases. There were no significant differences in overall CS between the revision and control group (p = 0.174) at final follow-up, but the control group scored significantly higher in the CS subgroups pain (p = 0.012) and internal rotation (p = 0.016). Mean SSV was significantly lower in the revision (65.5 ± 22.3%) compared to the control group (85.9 ± 16.4%; p = 0.031).

CONCLUSIONS

Bony regrowth at the distal clavicle presenting as postoperative AC-distance narrowing and new spur formation was observed more distinctly in the revision group. Despite a slight increase in postoperative outcomes after revision surgery, subjective satisfaction and recalcitrant pain remain a concern.

LEVEL OF EVIDENCE

Therapeutic Level III, retrospective case-control study.

Iatrogenic instability of the acromioclavicular joint leads to ongoing impairment of shoulder function even following secondary surgical stabilization

PURPOSE

Iatrogenic instability of the acromioclavicular joint (ACJ) following distal clavicle excision (DCE) represents an infrequent pathology. Revision surgery to restore ACJ stability and alleviate concomitant pain is challenging due to altered anatomic relationships. The purpose of this study was to evaluate the used salvage techniques and postoperative functional and radiological outcomes in retrospectively identify patients with a painful ACJ following DCE. We hypothesized that iatrogenic instability leads to ongoing impairment of shoulder function despite secondary surgical stabilization.

METHODS

9 patients with a painful ACJ after DCE (6 men, 3 women, 43.3 ± 9.4 years) were followed up at a minimum of 36 months after revision surgery. Besides range of motion (ROM), strength and function were evaluated with validated evaluation tools including the Constant score and the DASH score (Disability of the Arm, Shoulder and Hand questionnaire), specific AC Score (SACS), Nottingham Clavicle Score (NCS), Taft score and Acromioclavicular Joint Instability Score (AJI). Additionally, postoperative X-rays were compared to the unaffected side, measuring the coracoclavicular (CC) and acromioclavicular (AC) distance.

RESULTS

At follow-up survey (55.8 ± 18.8 months) all patients but one demonstrated clinical ACJ stability after arthroscopically assisted anatomical ACJ reconstruction with an autologous hamstring graft. Reconstruction techniques were dependent on the direction of instability. The functional results demonstrated moderate shoulder and ACJ scores with a Constant Score of 77.3 ± 15.4, DASH-score of 51.2 ± 23.4, SACS 32.6 ± 23.8, NCS 77.8 ± 14.2, AJI 75 ± 14.7 points and Taft Score 7.6 ± 3.4 points. All patients stated they would undergo the revision surgery again. Mean postoperative CC-distance (8.3 ± 2.8 mm) did not differ significantly from the contralateral side (8.5 ± 1.6 mm) (p > 0,05). However, the mean AC distance was significantly greater with 16.5 ± 5.8 mm compared to the contralateral side (3.5 ± 1.9 mm) (p = 0.012).

CONCLUSION

Symptomatic iatrogenic ACJ instability following DCE is rare. Arthroscopically assisted revision surgery with an autologous hamstring graft improved ACJ stability in eight out of nine cases (88.9%). However, the functional scores showed ongoing impairment of shoulder function and a relatively high overall complication rate (33.3%). Therefore, this study underlines the importance of precise preoperative indication and planning and, especially, the preservation of ACJ stability when performing AC joint resection procedures.

LEVEL OF EVIDENCE

Case series, LEVEL IV.

Arthroscopic-Assisted Coracoclavicular Stabilization With Anchorless Transosseous Double-Row Acromioclavicular Ligament Complex Repair: The Acute Acromioclavicular Joint Dislocation

The current concept procedures in the acute acromioclavicular joint dislocation should be divided into 2 types of structure restoration: those that provide coracoclavicular stabilization, which affects the primary healing of the coracoclavicular ligaments by vertically stabilizing the clavicle and coracoid in their anatomical positions, and those that attempt to repair the superior acromioclavicular ligament complex, which controls both horizontal and rotational stabilization. The acute acromioclavicular joint dislocation clinical outcome will be achieved if you perform both procedures. It's difficult to stabilize the acromioclavicular joint in both vertical and horizontal planes, and most current techniques aren't always effective. In this Technical Note, we discuss an arthroscopic-assisted technique that reconstructs the coracoclavicular and acromioclavicular ligaments under image intensifier guidance to achieve bidirectional (vertical and horizontal) and rotational stability.

Qualitative and Quantitative Anatomic Descriptions of the Coracoclavicular and Acromioclavicular Ligaments: A Systematic Review

Purpose

Methods

Results

Conclusions

Clinical Relevance

All-suture technique for fixation of unstable displaced distal clavicle fracture

Background

Displaced Neer type II and V clavicle fractures are usually treated surgically in active patients. However, distal fragment fixation remains a challenge, and no consensus has been established regarding the optimal surgical treatment. Osteosuture techniques have been popularized over the last decade, and multiple different techniques have been described. The aim of this study was to describe an all-suture technique in patients with displaced type II and V clavicle fractures and report its outcome in a prospective case series.

Methods

Between 2017 and 2020, 15 patients with displaced acute distal clavicle fractures were treated with an all-suture open technique performed by one shoulder specialized surgeon, with a minimum follow-up of 1 year. Osteosuture repair consisted in a coracoclavicular cerclage with 4 no6 Ethibonds and a figure-of-0 and figure-of-8 fracture cerclage with 2 no2 SutureTapes. Single assessment numerical evaluation (SANE) and adjusted Constant score were recorded at 6 months and 1 year. The radiologic union was assessed on plain radiographs.

Results

At 12 months, all patients reported excellent clinical results, with a mean SANE of 98.2 [± 5.2, range 80 to 100] and a mean adjusted Constant score of 99.0 [± 1.9, range 94 to 100]. One patient developed shoulder stiffness that resolved before the final follow-up. Fractures consolidated in 93% of the cases, with union happening between 3 and 6 months [range 3 to 12 months]. One patient developed an asymptomatic malunion.

Conclusion

Excellent clinical and radiological outcomes can be achieved with this minimally invasive all-suture fixation technique for displaced distal clavicle fractures, which allows for an anatomic reduction and stable fixation. This pilot study showed low complications and a high level of union after a follow-up of 1 year. Among the numerous advantages are a smaller exposure than for plate fixation, avoidance of hardware-related complications such as screw failure, coracoid fracture from drilling, or rotator cuff damage caused by hook-plates. Furthermore, it avoids a reoperation to remove symptomatic hardware.

Comparing the locking screw direction of three locking plates for lateral clavicle fractures: a simulation study

BACKGROUND

The locking plate is a useful treatment for lateral clavicle fractures, however, there are limits to the fragment size that can be fixed. The current study aimed to measure the screw angles of three locking plates for lateral clavicle fractures. In addition, to assess the number of screws that can be inserted in different fragment sizes, to elucidate the size limits for locking plate fixation.

METHODS

The following three locking plates were analyzed: the distal clavicle plate [Acumed, LLC, Oregon, the USA], the LCP clavicle plate lateral extension [Depuy Synthes, LLC, PA, the USA], and the HAI clavicle plate [HOMS Engineering, Inc., Nagano, Japan]. We measured the angles between the most medial and lateral locking screws in the coronal plane and between the most anterior and posterior locking screws in the sagittal plane. A computer simulation was used to position the plates as laterally as possible in ten normal three-dimensional clavicle models. Lateral fragment sizes of 10, 15, 20, 25, and 30 mm were simulated in the acromioclavicular joint, and the number of screws that could be inserted in the lateral fragment was assessed. Subsequently, the area covered by the locking screws on the inferior surface of the clavicle was measured.

RESULTS

The distal clavicle plate had relatively large screw angles (20° in the coronal plane and 32° in the sagittal plane). The LCP clavicle lateral extension had a large angle (38°) in the sagittal plane. However, the maximum angle of the HAI clavicle plate was 13° in either plane. The distal clavicle plate allowed most screws to be inserted in each size of bone fragment. For all locking plates, all screws could be inserted in 25 mm fragments. The screws of distal clavicle plate covered the largest area on the inferior surface of the clavicle.

CONCLUSIONS

Screw angles and the numbers of screws that could be inserted in the lateral fragment differed among products. Other augmented fixation procedures should be considered for fractures with fragment sizes < 25 mm that cannot be fixed with a sufficient number of screws.

Coronoid process reconstruction with a distal clavicle autograft: an in silico analysis of fitting accuracy

BACKGROUND

The coronoid process plays a vital role in preserving elbow stability. In cases of acute or chronic deficiency of the coronoid process, reconstruction is warranted to restore stability and to avoid early joint degeneration. The distal clavicle might be a useful osteochondral autograft for coronoid reconstruction with low donor-site morbidity. This study evaluated the fitting accuracy of the distal clavicle as an autograft for coronoid process reconstruction.

METHODS

One hundred upper-extremity computed tomography scans of 85 body donors were available for this study (mean age, 69 ± 17 years; 46 male and 39 female donors; 15 bilateral specimens). Standardized 40% transverse defects of the coronoid process were digitally created; the distal clavicles were digitally harvested and placed onto the defects by a best-fit technique in 2 different orientations using commercially available software: (1) with the superior aspect of the articular surface of the graft oriented toward the coronoid tip and (2) with the inferior aspect of the articular surface of the graft oriented toward the coronoid tip. The fitting accuracy of the grafts to the native coronoid process was evaluated from lateral to medial using custom code.

RESULTS

Regardless of the orientation of the graft, the distal clavicle provided a good fit in the central portion of the coronoid process. In the lateral and medial aspects of the defect, however, the fitting accuracy of the graft declined significantly (P ≤ .044). No significant differences were observed between ipsilateral and contralateral grafts (P ≥ .199). The intrarater reliability was excellent.

CONCLUSION

The results of this study suggest that a distal clavicle autograft may be suitable to replace a transverse defect of the coronoid process; however, it may not fully reconstruct the anteromedial and anterolateral aspects of the coronoid.

Quantitative and Qualitative Surgical Anatomy of the Acromioclavicular Joint Capsule and Ligament: A Cadaveric Study

BACKGROUND

The acromioclavicular (AC) capsule and ligament have been found to play a major role in maintaining horizontal stability. To reconstruct the AC capsule and ligament, precise knowledge of their anatomy is essential.

PURPOSE/HYPOTHESIS

The purposes of this study were (1) to determine the angle of the posterosuperior ligament in regard to the axis of the clavicle, (2) to determine the width of the attachment (footprint) of the AC capsule and ligament on the acromion and clavicle, (3) to determine the distance to the AC capsule from the cartilage border of the acromion and clavicle, and (4) to develop a clockface model of the insertion of the posterosuperior ligament on the acromion and clavicle. It was hypothesized that consistent angles, attachment areas, distances, and insertion sites would be identified.

STUDY DESIGN

Descriptive laboratory study.

METHODS

A total of 12 fresh-frozen shoulders were used (mean age, 55 years [range, 41-64 years]). All soft tissue was removed, leaving only the AC capsule and ligament intact. After a qualitative inspection, a quantitative assessment was performed. The AC joint was fixed in an anatomic position, and the attachment angle of the posterosuperior ligament was measured using a digital protractor. The capsule and ligament were removed, and a coordinate measuring device was utilized to assess the width of the AC capsule footprint and the distance from the footprint to the cartilage border of the acromion and clavicle. The AC joint was then disarticulated, and the previously marked posterosuperior ligament insertion was transferred into a clockface model. The mean values across the 12 specimens were demonstrated with 95% CIs.

RESULTS

The mean attachment angle of the posterosuperior ligament was 51.4° (95% CI, 45.2°-57.6°) in relation to the long axis of the entire clavicle and 41.5° (95% CI, 33.8°-49.1°) in relation to the long axis of the distal third of the clavicle. The mean clavicular footprint width of the AC capsule was 6.4 mm (95% CI, 5.8-6.9 mm) at the superior clavicle and 4.4 mm (95% CI, 3.9-4.8 mm) at the inferior clavicle. The mean acromial footprint width of the AC capsule was 4.6 mm (95% CI, 4.2-4.9 mm) at the superior side and 4.0 mm (95% CI, 3.6-4.4 mm) at the inferior side. The mean distance from the lateral clavicular attachment of the AC capsule to the clavicular cartilage border was 4.3 mm (95% CI, 4.0-4.6 mm), and the mean distance from the medial acromial attachment of the AC capsule to the acromial cartilage border was 3.1 mm (95% CI, 2.9-3.4 mm). On the clockface model of the right shoulder, the clavicular attachment of the posterosuperior ligament ranged from the 9:05 (range, 8:00-9:30) to 11:20 (range, 10:00-12:30) position, and the acromial attachment ranged from the 12:20 (range, 11:00-1:30) to 2:10 (range, 13:30-14:40) position.

CONCLUSION

The finding that the posterosuperior ligament did not course perpendicular to the AC joint but rather was oriented obliquely to the long axis of the clavicle, in combination with the newly developed clockface model, may help surgeons to optimally reconstruct this ligament.

CLINICAL RELEVANCE

Our results of a narrow inferior footprint and a short distance from the inferior AC capsule to cartilage suggest that proposed reconstruction of the AC joint capsule should focus primarily on its superior portion.

Mini open triple tunnel- double flip button techniques in treatment of acute acromioclavicular joint injuries: Case report

Acute acromioclavicular (AC) joint injuries are common and often occur in a contact sport activity. Most acute AC joint injuries surgery techniques focus on coracoclavicular (CC) ligament complex fixation; by single or double clavicle tunnel, but persisting vertical instability. In this paper, we introduce mini open triple tunnel- double flip button (TTDB) technique for acute AC joint dislocation by adding tunnel on clavicle to expand coverage of footprint of conoid and trapezoid ligament in order to improve vertical stability of the AC joint. This method is based on CC ligament augmentation with a double flip button/polydioxanone (PDS), combined with V-loop pulley suture for anatomical fixation. This is a prospective case report. Two professional, male basketball players in this study with a mean age of 25 years underwent surgery in 2019. Clinical subjective outcome, VAS score, Nottingham Clavicle Score, and radiological CC distance were measured before and after the operation. There were noticeable improvement in the patients' recovery after two years since the operation. We introduce TTDB technique as one of the open techniques for acute AC joint injuries in limited-resource hospital setting.

New possibilities: the LockDown device for distal clavicle fractures

Background and hypothesis

The majority of distal clavicle fractures are displaced fractures and constitute a treatment challenge because they have a 30% chance of delayed union or nonunion. Although several options for surgical reconstruction have been described, in patients with a comminuted and/or small distal fragment, these reconstructive options have proved to be prone to failure. Moreover, secondary surgery for removal is necessary in most cases. We hypothesized that the LockDown device, a braided synthetic ligament device, combined with resection of the distal fracture fragment is a suitable alternative in specified patients with distal clavicle fractures.

Methods

Eleven patients with distal clavicle fractures were treated with distal fracture resection and the LockDown procedure. All patients underwent regular follow-up with data collection; additionally, 7 were assessed at 1-year follow-up according to the study protocol. On the basis of radiography, these patients had a clear coracoclavicular ligament disruption and subsequent cranial dislocation of the medial fragment. Regular follow-up was performed at 6 weeks, 3 months, and 6 months. Control radiographs were taken at 3 and 6 months. Furthermore, the 7 enrolled patients were assessed at 1 year, when the Disabilities of the Arm, Shoulder and Hand score, Constant shoulder score, Nottingham Clavicle Score, and range of motion were recorded. Residual pain was ascertained by a visual analog scale score.

Results

In total, 11 patients were treated with distal clavicle resection and the LockDown procedure. Eight patients underwent surgery within 3 weeks after presentation at the emergency department. The other 3 patients were operated on after a trial of conservative treatment (due to persisting pain and delayed union). None of the patients had postoperative complications. At 3 months, 9 of the 11 patients had made a full recovery.

Discussion

All 11 patients had good short-term clinical outcomes. None showed acromioclavicular instability. Furthermore, secondary surgery was avoided, and hardware complications did not occur. In low-demand patients or patients with a high risk of nonunion, this technique may be a favorable alternative to other known techniques.

Surgical techniques for management of acromioclavicular joint separations: review and update for radiologists

Imaging plays a central role in the postoperative management of acromioclavicular (AC) joint separations. There are more than 150 described techniques for the surgical management of AC joint injuries. These procedures can be categorized as varying combinations of the following basic techniques: a) soft-tissue repair, b) trans-articular AC joint fixation, c) coracoclavicular (CC) fixation, d) non-anatomic reconstruction of the CC ligaments, e) anatomic reconstruction of the CC ligaments, f) distal clavicle resection, and g) dynamic muscle transfer. The goals of this article are to describe the basic techniques for the surgical management of AC joint separations with an emphasis on technique-specific complications and postoperative imaging assessment.

Klavikularekonstruktion bei Pseudarthrose nach lateraler Klavikulafraktur

Laterale Klavikulafrakturen machen einen Anteil von bis zu 28 % aller Klavikulafrakturen aus und neigen zur Entstehung von Pseudarthrosen. In diesem Beitrag wird ein spezielles Operationsverfahren beschrieben. Hierbei erfolgte die Therapie durch eine Resektion des lateralen Fragments und Rekonstruktion der lateralen Klavikula mit Beckenkammspan sowie Hakenplattenfixierung, was nachfolgend zur Ausbildung eines Neo-Akromioklavikulargelenks (ACG) führte. Die 43-jährige Patientin klagte über bewegungsabhängige und Dauerschmerzen aufgrund einer lateralen Klavikulafraktur vor einem Jahr. Die klinische Untersuchung zeigte einen Druckschmerz im Bereich des ACG und einen positiven Cross-body-Test. In der bildgebenden Diagnostik (MRT und Röntgen) zeigt sich die Pseudarthrose im Bereich der lateralen Klavikula (Neer I, Jäger/Breitner I). Ziel dieser Arbeit war die Demonstration der Rekonstruktion des ACG mit Hakenplattenfixierung und Beckenkammspan. Im Follow-up zeigte sich eine gute Rekonstruktion der lateralen Klavikula unter Ausbildung eines Neo-ACG mit freier Beweglichkeit des Schultergelenks ohne Schmerzen.

Functional outcome of open acromioclavicular joint stabilization for instability following distal clavicle resection

Background

Acromioclavicular joint instability following distal clavicle resection can result in considerable pain and dysfunction.

Method

We present a review of 13 patients who underwent ACJ stabilization following one or more distal clavicle resection procedures.

Results

The mean Quick DASH and CM scores were 26(0-57) and 73(46-100) respectively. All but one patient reported an improvement in the pain component of their CM score and in the work component of the Quick DASH score.

Discussion

Open ACJ stabilization to treat instability following distal clavicle resection resulted in improved functional scores, pain scores and facilitated return to work in most patients.Level of evidence IV.

Medialized Clavicular Bone Tunnel Position Predicts Failure After Anatomic Coracoclavicular Ligament Reconstruction in Young, Active Male Patients

BACKGROUND

Recent radiographic data have suggested that medialized conoid tunnel placement greater than 25% of absolute clavicular length is correlated with early failure after anatomic coracoclavicular ligament reconstructions. A comparison with a larger active duty military cohort of clinical and radiographic outcomes can serve as a basis for standardizing surgical technique.

PURPOSE

To establish the ideal radiographic tunnel position for anatomic coracoclavicular ligament reconstruction and to elucidate variables associated with early loss of reduction and ability to return to active-duty military service.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A retrospective review of the military's electronic medical record between the years 2000 and 2013 was performed. All anatomic coracoclavicular reconstructions at a single institution were included for analysis, and nonanatomic or revision reconstructions were excluded. Radiographic failure was defined as 6 mm of superior clavicle displacement on immediate postoperative films.

RESULTS

A cohort of 38 patients underwent 39 anatomic coracoclavicular reconstructions. Average follow-up time was 26 months (range, 1.2-92 months). A total of 20 radiographic failures were identified, with an average conoid tunnel ratio of 0.27. When conoid tunnel ratios were compared with a reference ratio of 0.20 to 0.25, increased risk of failure was statistically significant with lateralization greater than 0.20 (P = .018; odds ratio [OR] = 40 [95% CI, 1.05-999.06]) or with medialization of 0.251 to 0.30 (P = .002; OR = 39 [95% CI, 1.58-944.36]) or greater than 0.30 (P = .029; OR = 21 [95% CI, 0.77-562.15]). Medialization of the trapezoid position greater than 0.16 (vs a range of 0.13-0.16) was also found to be significant for failure (P < .023; OR = 8 [95% CI, 1.33-48.18]). However, these significant findings did not correlate with symptoms or ability to return to duty (P > .05).

CONCLUSION

The optimal technique for treating acromioclavicular separations has yet to be determined. Recently, anatomic coracoclavicular reconstruction has demonstrated biomechanical superiority to previously described methods. The findings of optimal tunnel positioning in anatomic reconstructions from this large active-duty military cohort can assist preoperative planning to reduce failure rates when treating these difficult injuries.

BIOMECHANICAL COMPARISON OF THE CORACOCLAVICULAR SPACE FIXATION USING THREE DIFFERENT SUTURE TECHNIQUES

Coracoclavicular space fixation with suture loops is a well-known surgical technique for the treatment of dislocations. However, out of 100 different surgical treatments no single one has been established as a gold standard. The following research aims to improve the technique and focuses on a development of new fixation technique using composite sutures, which would withstand forces during ligament healing process. Three different fixation techniques (one loop and two separate suture loops and W-system) were tested on a custom built mechanical testing device. Applied load was continuously increased at a loading rate of 30[Formula: see text]N/min until the failure of the sutures. Ultimate tensile strength and suture elongation at failure were measured. The W-system had statistically significant higher load to failure and higher stiffness compared to one loop and two separate loops techniques. Biomechanical properties of a suture fixation technique can be improved by connecting them into one system to create particular arrangement of the sutures. The measurements can be easily repeated and this testing protocol can serve as a good starting point to standardize procedures of evaluation of different joint fixation techniques and to develop new ones.

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).

Acromioclavicular joint instability: anatomy, biomechanics and evaluation

Acromioclavicular (AC) joint instability is a common source of pain and disability. The injury is most commonly a result of a direct impact to the AC joint. The AC joint is surrounded by a capsule and has an intra-articular synovium and an articular cartilage interface. An articular disc is usually present in the joint, but this varies in size and shape. The AC joint capsule is quite thin, but has considerable ligamentous support; there are four AC ligaments: superior, inferior, anterior and posterior. The coracoclavicular (CC) ligament complex consists of the conoid and trapezoid ligaments. They insert on the posteromedial and anterolateral region of the undersurface of the distal clavicle, respectively. The coracoid origin of the trapezoid covers the posterior half of the coracoid dorsum; the conoid origin is more posterior on the base of the coracoid. Several biomechanical studies showed that horizontal stability of the AC joint is mediated by the AC ligaments while vertical stability is mediated by the CC ligaments. The radiographic classification of AC joint injuries described by Rockwood includes six types: in type I injuries the AC ligaments are sprained, but the joint is intact; in type II injuries, the AC ligaments are torn, but the CC ligaments are intact; in type III injuries both the AC and the CC ligaments are torn; type IV injuries are characterized by complete dislocation with posterior displacement of the distal clavicle into or through the fascia of the trapezius; type V injuries are characterized by a greater degree of soft tissue damage; type VI injuries are inferior AC joint dislocations into a subacromial or subcoracoid position. The diagnosis of AC joint instability can be based on historical data, physical examination and imaging studies. The cross body adduction stress test has the greatest sensitivity, followed by the AC resisted extension test and the O'Brien test. Proper radiographic evaluation of the AC joint is necessary. The Zanca view is the most accurate view for examining the AC joint. The axial view of the shoulder is important in differentiating a type III AC joint injury from a type IV injury.

How long should arthroscopic clavicular resection be in acromioclavicular arthropathy? A radiological-clinical study (with computed tomography) of 18 cases at a mean 4 years' follow-up

INTRODUCTION

Endoscopic clavicular resection is a common procedure, but few studies have analyzed predictive factors for outcome.

HYPOTHESES

1) Computed tomography (CT) of clavicular resection is reproductible; 2) Functional outcome correlates with resection length; 3) Other factors also influence outcome.

MATERIAL AND METHODS

Patients operated on between 2005 and 2010 were called back to establish functional scores (Constant, Simple Shoulder Test [SST], satisfaction) and undergo low-dose bilateral comparative computed tomography (CT) centered on the acromioclavicular joints. The assessment criteria were resection edge parallelism and resection length, measured using OsiriX software. Radiological and clinical data were correlated.

RESULTS

18 out of 21 patients (85%: 3 female, 15 male) were assessed. Mean age at surgery was 49 years (range, 40-62 yrs); mean follow-up was 4.2 years (1.6-7.2 yrs). Mean Constant score rose from 57.7 (25-85) to 70.2 (30-96); mean postoperative SST was 9.3 (3-12). 11 patients had very good and 4 poor results. CT resection length was reproducible, with intraclass, intra- and interobserver correlation coefficients >95%. There was no significant correlation between articular resection length on CT and functional scores (P=0.2). Functional scores were negatively influenced by an occupational pathologic context (P<0.01) and by associated tendinopathy.

DISCUSSION AND CONCLUSION

Low-dose CT enabled reproducible analysis of clavicular resection. The hypothesized correlation between resection length and functional result was not confirmed. Work accidents and occupational disease emerged as risk factors.

LEVEL OF EVIDENCE

Single-center retrospective analytic cohort study. Level 4, guideline grade C.

Comparison between open and arthroscopic procedures for lateral clavicle resection

PURPOSE

Arthroscopic lateral clavicle resection (LCR) is increasingly used, compared to an open approach, but literature does not clearly indicate which approach is preferable. The goal of this study was to compare function and pain between patients who underwent lateral clavicle resection using an open approach and patients treated using an arthroscopic approach.

METHODS

Patients who underwent LCR between January 2008 and December 2011 were reviewed. After exclusion, 149 shoulders (143 patients) were eligible for analysis: 41 open and 108 arthroscopic. Disabilities of arm, shoulder and hand (DASH) questionnaire and visual analogue scale (VAS) score were used to assess shoulder function and pain. Complications, operative time, length of hospitalization and resection distance were compared.

RESULTS

At a mean follow-up of three years, patients in the open group had significantly less pain by VAS (mm) (Mdn 10, IQR 23) compared with arthroscopic patients (Mdn 20, IQR 50) (p = 0.036). Operative time (minutes) was significantly less for the open approach (Mdn 24.0, IQR 12) compared with arthroscopic (Mdn 38.0, IQR 15) (p < 0.001). Resection distance (mm) was larger for the open approach (Mdn 7.1, IQR 7.0) compared with the arthroscopic approach (Mdn 3.2, IQR 3.1) (p = 0.006), but was not associated with outcome. No significant differences were found for DASH score, complication rate or length of hospitalization.

CONCLUSIONS

Both arthroscopic and open approaches for LCR provide excellent outcome in patients with acromioclavicular pain. Less residual pain was found for the open approach, which has shorter operating time and is likely more cost effective.

Analysis of neurovascular safety between superior and anterior plating techniques of clavicle fractures

OBJECTIVES

Clavicle fractures are commonly plated as a method of fixation, with superior and anterior techniques described. Although advantages and disadvantages have been attributed to both, it is unclear if one approach provides a lower risk of neurovascular injury. The aim of this study was to compare the potential for neurovascular injury between these 2 plate locations in a cadaveric model.

METHODS

Seventeen adult fresh frozen cadavers underwent bilateral dissections exposing the clavicle and underlying neurovasculature. After taking baseline anatomical measurements, a superior and anterior clavicle plate was applied, removed and measurements were taken from the nearest screw exit site to the underlying subclavian vein/artery and brachial plexus. The differences between superior and anterior measurements were compared based on proximity with the neurovasculature.

RESULTS

Distance to the vessels were unobtainable in 6 specimens (35%) plated with the anterior technique due to the trajectory of the screws projecting cephalad to the vessels. In the remaining specimens, there was no significant difference in the distance to the subclavian vein/artery and brachial plexus in the superior plate position (9.2 ± 4.6, 12.2 ± 5.8, and 9.8 ± 5.2 mm, respectively) compared with the anterior plate position (8.3 ± 3.5, 12.2 ± 6.5, and 9.7 ± 5.3 mm, respectively). In addition, no significant difference in potential neurovascular injury with regard to body size or gender was found.

CONCLUSIONS

The majority of our specimens showed no significant difference between superior and anterior plating in regard to potential risk for injury to the underlying neurovasculature. However, there appears to be a subset of the population with a more caudal position of the neurovascular structures in which anterior plating may be potentially safer.

Degenerative joint disease of the acromioclavicular joint: a review

Osteoarthritis of the acromioclavicular (AC) joint is a common condition causing anterior or superior shoulder pain, especially with overhead and cross-body activities. This most commonly occurs in middle-aged individuals because of degeneration to the fibrocartilaginous disk that cushions the articulations. Diagnosis relies on history, physical examination, imaging, and diagnostic local anesthetic injection. Diagnosis can be challenging given the lack of specificity with positive physical examination findings and the variable nature of AC joint pain. Of note, symptomatic AC osteoarthritis must be differentiated from instability and subtle instability, which may have similar symptoms. Although plain radiographs can reveal degeneration, diagnosis cannot be based on this alone because similar radiographic findings can be seen in asymptomatic individuals. Nonoperative therapy can provide symptomatic relief, whereas patients with persistent symptoms can be considered for resection arthroplasty by open or arthroscopic technique. Both techniques have proven to provide predictable pain relief; however, each has its own unique set of potential complications that may be minimized with an improved understanding of the anatomical and biomechanical characteristics of the joint along with meticulous surgical technique.

The biomechanical stability of distal clavicle excision versus symmetric acromioclavicular joint resection

BACKGROUND

Treatment for acromioclavicular (AC) joint pain may include distal clavicle excision (DCE). It is possible that DCE can disrupt the surrounding ligaments, leading to increased AC joint laxity.

PURPOSE

To determine the load to failure and stiffness of the AC joint after DCE and symmetric acromioclavicular joint resection (ACJR).

STUDY DESIGN

Controlled laboratory study.

METHODS

Specimens were randomly assigned to 1 of 2 groups: 1-cm DCE (n = 10) or symmetric (5-mm excision of acromion and distal clavicle) ACJR (n = 10). The specimens were loaded intact in the anterior-posterior plane to determine anteroposterior translation. This was repeated after surgery and compared. The specimens were loaded at 2 mm/s until clinical failure. Force and displacement were recorded, and stiffness was calculated.

RESULTS

The peak load to failure for the DCE group was 387.8 N (standard error of the mean [SEM], 31.4 N) and for the ACJR group was 468.5 N (SEM, 30.9 N) (P = .035). The average stiffness for the DCE group was 35.2 N/mm (SEM, 2.5 N/mm) and for the ACJR group was 37.4 N/mm (SEM, 2.3 N/mm) (P = .11). There was no significant difference in the anteroposterior translation before and after resection for either group (P > .05).

CONCLUSION

This cadaveric study demonstrates that the anterior-posterior load to clinical failure of the AC joint after 5 mm of resection from the distal clavicle and medial acromion is significantly greater than 1 cm of the resected distal clavicle alone.

CLINICAL RELEVANCE

Performing ACJR may improve joint stability, leading to fewer complications when compared with DCE.

Clavicular bone tunnel malposition leads to early failures in coracoclavicular ligament reconstructions

BACKGROUND

Modern techniques for the treatment of acromioclavicular (AC) joint dislocations have largely centered on free tendon graft reconstructions. Recent biomechanical studies have demonstrated that an anatomic reconstruction with 2 clavicular bone tunnels more closely matches the properties of native coracoclavicular (CC) ligaments than more traditional techniques. No study has analyzed tunnel position in regard to risk of early failure.

PURPOSE

To evaluate the effect of clavicular tunnel position in CC ligament reconstruction as a risk of early failure.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A retrospective review was performed of a consecutive series of CC ligament reconstructions performed with 2 clavicular bone tunnels and a free tendon graft. The population was largely a young, active-duty military group of patients. Radiographs were analyzed for the maintenance of reduction and location of clavicular bone tunnels using a picture archiving and communication system. The distance from the lateral border of the clavicle to the center of each bone tunnel was divided by the total clavicular length to establish a ratio. Medical records were reviewed for operative details and functional outcome. Failure was defined as loss of intraoperative reduction.

RESULTS

The overall failure rate was 28.6% (8/28) at an average of 7.4 weeks postoperatively. Comparison of bone tunnel position showed that medialized bone tunnels were a significant predictor for early loss of reduction for the conoid (a ratio of 0.292 vs 0.248; P = .012) and trapezoid bone tunnels (a ratio of 0.171 vs 0.128; P = .004); this correlated to an average of 7 to 9 mm more medial in the reconstructions that failed. Reconstructions performed with a conoid ratio of ≥0.30 were significantly more likely to fail (5/5, 100%) than were those performed lateral to a ratio of 0.30 (3/23, 13.0%) (P < .01). There were no failures when the conoid ratio was <0.25 (0/10, 0%). Conoid tunnel placement was also statistically significant for predicting return to duty in our active-duty population.

CONCLUSION

Medial tunnel placement is a significant factor in risk for early failures when performing anatomic CC ligament reconstructions. Preoperative templating is recommended to evaluate optimal placement of the clavicular bone tunnels. Placement of the conoid tunnel at 25% of the clavicular length from the lateral border of the clavicle is associated with a lower rate of lost reduction and a higher rate of return to military duty.

Medial coracoclavicular ligament revisited: an anatomic study and review of the literature

The medial coracoclavicular ligament (MCCL), up to now rarely reported in the literature, was studied in a formol-fixed cadaver by means of dissection, morphometry, and light microscopy. This entity represents a true ligament within the coracoclavicular fascia. Although longer and narrower than its lateral counterpart, the medial coracoclavicular ligament follows the same morphological pattern, including the cartilage at the level of the coracoidal attachment. Its clinical significance and implications together with a review of the literature is presented.

The evaluation and management of failed distal clavicle excision

Excision of the distal clavicle (DCE) is a commonly carried out surgical procedure used in the management of acromioclavicular joint pathology. Although successful outcomes after both open and arthroscopic distal clavicle excision occur in a high percentage of patients, treatment failures have been reported, creating a difficult clinical scenario for the treating orthopedic surgeon. The most common mode of failure after DCE is persistent pain and potential etiologies include under-resection, over-resection leading to joint instability, postoperative stiffness, heterotopic ossification, untreated concomitant shoulder pathology, and postoperative infection. Less common causes of failure include distal clavicle fracture, reossification or fusion across the acromioclavicular joint, suprascapular neuropathy, and psychiatric illness. Persistent symptoms and disability after distal clavicle excision require a careful assessment of these potential causes of treatment failure and the formulation of a treatment plan, which may include conservative care, revision surgery, or coracoclavicular ligament reconstruction. Although careful patient selection, preoperative planning, proper surgical technique, and appropriate rehabilitation during the index procedure can minimize the likelihood of poor outcome, this paper reviews the work-up and management of cases of failed distal clavicle excision.

Analysis of the capsule and ligament insertions about the acromioclavicular joint: a cadaveric study

PURPOSE

The purpose of this study was to analyze the capsular and ligamentous insertions about the acromioclavicular (AC) joint to determine the amount of bone that can be removed without destabilizing the joint.

METHODS

We dissected 28 cadaveric shoulders. The AC ligament insertions were measured under loupe magnification with a digital caliper on the acromial and clavicular sides on the anterior, posterior, superior, and inferior edges. We measured the distance to the coracoacromial (CA) and coracoclavicular ligaments. In addition, the axial and coronal angle of the AC joint was measured.

RESULTS

The AC joint capsular insertion on the acromion begins, on average, 2.8 mm (range, 2.3 to 3.3 mm) from the medial acromion and begins on the lateral clavicle a mean of 3.5 mm (range, 2.9 to 3.9 mm) from the distal clavicle. The mean capsular width ranged from 1.6 to 2.9 mm. The mean distance from the medial acromion to the CA ligament insertion was 3.5 mm. The mean axial angle of the AC joint was 51 degrees , with a 12 degrees coronal angle. The mean distance from the lateral clavicle to the start of the trapezoid ligament was 14.7 mm, and that to the conoid ligament was 32.1 mm.

CONCLUSIONS

An anatomic-based recommendation for safe AC joint resection is that 2 to 3 mm of the medial acromion and 3 to 4 mm of the distal clavicle can be resected without removing the AC capsular insertions. The trapezial and CA attachments are in close proximity to the AC capsular insertions. Medial resections greater that 15 mm will begin to take down the trapezoid ligament. Arthroscopic bone resection should be directed into the AC joint at approximately 50 degrees in the axial plane and 12 degrees in the coronal plane for safe symmetric resection.

CLINICAL RELEVANCE

These anatomic measurements suggest that AC joint resections (5 to 7 mm) with 2 to 3 mm from the acromial side and 3 to 4 mm from the clavicular side will not disrupt the stabilizing ligaments of the AC joint after distal clavicle resection.

Suspension suture augmentation for repair of coracoclavicular ligament disruptions

Surgical reconstruction of the coracoclavicular ligament is a fundamental part of management of high-grade acromioclavicular dislocations and Type II lateral third clavicular fractures. However, no single surgical procedure is fully satisfactory because of failure or complications. We present an alternative coracoclavicular stabilization technique, which avoids the use of hardware or tendon graft, that was used in 10 consecutive patients with complete coracoclavicular ligament disruptions. These patients were followed for a minimum of 14 months (average, 34.8 months; range, 14-55 months). At the final followup, functional outcome measurement instruments (University of California-Los Angeles shoulder rating system and Western Ontario Shoulder Instability Index) and radiographic analysis were adopted as the main outcome measures of shoulder function. The mean University of California-Los Angeles shoulder rating score and the mean Western Ontario Shoulder Instability Index aggregation score at 12 months after surgery were 33.8 (95% confidence interval, 32.8-34.8) and 93.4 (95% confidence interval, 88.2-98.6), respectively. The radiographic analysis revealed all patients had maintained reduction on radiographs at the final followup. These preliminary results suggest that this simple technique can achieve stable coracoclavicular reconstruction and facilitate healing of the repaired ligaments or fractures.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

The coracoidal insertion of the coracoclavicular ligaments: an anatomic study

BACKGROUND

Current surgical procedures restoring a dislocated acromioclavicular joint aim to perform an anatomically correct and biomechanically stable reconstruction. However, the coracoidal insertions for the coracoclavicular ligaments have not yet been defined.

PURPOSE

The objective was to evaluate dimension and orientation of the coracoclavicular footprints with respect to bony landmarks for use in anatomic reconstruction of the coracoclavicular ligament complex.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Twenty-three (17 female, 6 male) fresh-frozen cadaveric human shoulders were dissected, and the coracoclavicular ligaments including the coracoid and the lateral clavicle were exposed. After measurement of bony coracoidal dimensions, the ligaments were dissected and the insertion sites as well as the footprint centers were identified and marked. Each coracoclavicular insertion dimension and its distance to the bony landmarks was recorded. Sex-related differences were calculated.

RESULTS

The mean total coracoidal length was 43.1 +/- 2.2 mm. The distance from the tip of the coracoid to the precipice, the point at which the undersurface of the coracoid changes from a horizontal to a vertical direction, measured 20.3 +/- 2.6 mm. The mean distance from the conoidal center to the medial coracoidal boarder and to the precipice was 1.7 +/- 0.7 mm and 16.4 +/- 2.4 mm, respectively. The mean distance from the trapezoidal center to the medial border and to the precipice was 8.7 +/- 3 mm and 10.9 +/- 2.4 mm, respectively. The mean distance between the footprint centers was 10.1 +/- 4.2 mm.

CONCLUSION

Reproducible dimensions and orientation of the coracoclavicular footprints are given.

CLINICAL RELEVANCE

Coracoidal anatomic landmarks can be used intraoperatively for an anatomic reconstruction of the coracoclavicular ligaments.

MR imaging appearances of acromioclavicular joint dislocation

The key structures involved in dislocation of the acromioclavicular joint (ACJ) are the joint itself and the strong accessory coracoclavicular ligament. ACJ dislocations are classified with the Rockwood system, which comprises six grades of injury. Treatment planning requires accurate grading of the ACJ disruption, but correct classification can be difficult with clinical assessment. Magnetic resonance (MR) imaging has a well-established role in evaluation of ACJ pain. MR imaging performed in the coronal oblique plane parallel to the distal clavicle allows assessment of the acromioclavicular and coracoclavicular ligaments owing to its in-plane orientation in relation to these structures. This technique enables distinction between grade 2 and grade 3 injuries, which can be difficult with conventional clinical and radiographic evaluation. In addition, diagnosis of grade 1 injuries is possible by demonstration of a ruptured superiodorsal acromioclavicular ligament. Resultant thickening of the acromioclavicular or coracoclavicular ligament allows identification of chronic ACJ injuries.

Minimally invasive coracoclavicular stabilization with suture anchors for acute acromioclavicular dislocation

BACKGROUND

The management of acute acromioclavicular (AC) joint dislocation is controversial.

PURPOSE

The authors describe a surgical technique involving securing the clavicle to the coracoid process using suture anchors for the treatment of acute AC joint injury.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Twenty patients were evaluated retrospectively, clinically, and radiographically, for a mean of 41.2 months.

RESULTS

At last follow-up, the mean Constant score for the 20 patients was 89.5. Eighteen patients (90%) maintained complete AC joint reduction in both anteroposterior and axillary views. Slight loss of reduction was noted in 2 patients (10%), but their functional outcomes were good. No fixation failure or pulling out of suture anchors was encountered.

CONCLUSION

This minimally invasive technique using a suture anchor for the treatment of acute AC dislocation is easily performed.

A modified technique of arthroscopically assisted AC joint reconstruction and preliminary results

Surgical treatment of high-grade acromioclavicular (AC) joint separations has become analogous to ligament reconstructions elsewhere in the body with the goal being restoration of the native anatomy. Circumferential access to the base of the coracoid is essential to reconstruct the coracoclavicular ligament complex. Using some of the traditional open approaches, this access requires detaching the deltoid insertion and performing extensive soft tissue dissection. Also, poor visualization risks injury to nearby neurovascular structures. An arthroscopically assisted reconstruction offers the advantage of less soft tissue dissection and superior visualization to the base of the coracoid. We have developed a unique arthroscopically assisted technique that uses a subacromial approach to pass suture material and a tendon graft around the coracoid to reconstruct the coracoclavicular ligament complex. We describe our technique and preliminary results in 10 patients who have undergone coracoclavicular ligament reconstruction for high-grade AC separation. All patients improved subjectively with regard to pain and function at a minimum followup of 3 months (mean, 5 months; range, 3-18 months). This arthroscopically assisted technique has the potential to allow for safe and at least in the short term reliable restoration of the coracoclavicular ligament complex and provides an alternative technique to treat AC joint separations.

Anatomy of the clavicle and coracoid process for reconstruction of the coracoclavicular ligaments

BACKGROUND

Recently acromioclavicular joint reconstruction techniques have focused on anatomic restoration of the coracoclavicular (CC) ligaments. Such techniques involve creating bone tunnels in the distal clavicle and coracoid.

PURPOSE

To define the anatomy of the human clavicle and coracoid process of the scapula, in order to guide surgeons in reconstructing the CC ligaments.

STUDY DESIGN

Descriptive laboratory study.

METHODS

One hundred twenty (60 paired) cadaveric clavicles and corresponding scapulae (mean age +/- and standard deviation, 48.3 +/- 16.6 years) devoid of soft tissue were analyzed (dry osteology). Differences related to race and sex were recorded. Nineteen fresh-frozen cadaveric clavicles with intact CC ligaments were measured as well (fresh anatomic).

RESULTS

The mean clavicle length was 149 +/- 9.1 mm. In the dry osteology group, the distance from the lateral edge of the clavicle to the medial edge of the conoid tuberosity in male and female specimens was 47.2 +/- 4.6 mm and 42.8 +/- 5.6 mm, respectively (P = .006). The distance to the center of the trapezoid tuberosity was 25.4 +/- 3.7 mm in males and 22.9 +/- 3.7 mm in females (P = .04). The ratio of the distance to the medial edge of the conoid tuberosity divided by clavicle length was 0.31 in males and females. This ratio for the trapezoid was 0.17 in both sexes. The mean coracoid length was 45.2 +/- 4.1 mm. The mean width and height of the coracoid process were 24.9 +/- 2.5 mm and 11.9 +/- 1.8 mm, respectively. No interracial differences in measurements were observed. In the fresh anatomic samples, the ratio of the distance to the conoid center to clavicle length was 0.24. This ratio for the trapezoid was 0.17.

CONCLUSIONS

While absolute differences in the origin of the CC ligaments exist between men and women, the ratio of these origins to total clavicle length is constant.

CLINICAL RELEVANCE

Clavicle length can be obtained intraoperatively. These findings allow the surgeon to predict the origin of the conoid and trapezoid ligaments accurately and to correctly create bone tunnels to reconstruct the anatomy of the CC complex.

Ultrasonography for intraoperative control of the amount of bone resection in arthroscopic acromioclavicular joint resection

Remaining superior osteophytes or osseous spurs after arthroscopic lateral clavicle resection can cause persistent pain and could lead to revision surgery. A new method of intraoperative ultrasonographic imaging of the result of the operation during arthroscopic lateral clavicle resection is presented. In 10 patients with acromioclavicular arthritis, standardized arthroscopic lateral clavicle resection was performed. Intraoperatively, the space between the clavicle and the acromion was measured before and after arthroscopic acromioclavicular resection using a Sonosite 180 plus (SonoSite, Bothell, WA) with a 10-MHz broadband linear array in a sterile bag. The width of the joint space between the clavicle and the acromion was between 0.38 and 0.56 cm before operation and 0.92 cm and 1.28 cm after operation (nine cases). In one case, the anticipated minimum resection of 0.5 cm was not achieved at the sonographic measurement and further resection was required. Real-time ultrasonography allows exact measurement of the amount of resected bone during arthroscopic lateral clavicle resection. This could avoid revision surgery resulting from persisting disability caused by insufficient or extensive bone resection.