Arthroscopic shoulder instability surgery. Complications

Safety and efficacy of hyperosmolar irrigation solution in shoulder arthroscopy

BACKGROUND

A hyperosmolar irrigation solution has been reported to be safe and have potential benefits for use during shoulder arthroscopy in an animal model study. In this study, the clinical effects of a hyperosmolar solution were compared with a standard isotonic solution when used for shoulder arthroscopy.

METHODS

A prospective, double-blind, randomized controlled trial was performed to compare isotonic (273 mOsm/L) and hyperosmolar (593 mOsm/L) irrigation solutions used for arthroscopic rotator cuff repair. Primary outcomes focused on the amount of periarticular fluid retention based on net weight gain, change in shoulder girth, and pain. All patients were tracked through standard postsurgical follow-up to ensure no additional complications arose. Patients were contacted at 1 year to assess American Shoulder and Elbow Surgeon score, visual analog scale pain score, and the Single Assessment Numeric Evaluation shoulder scores RESULTS: Fifty patients (n = 25/group) were enrolled and completed the study. No statistically significant differences were noted between cohorts in demographics or surgical variables. The hyperosmolar group experienced significantly less mean weight gain (1.6 ± 0.82 kg vs. 2.25 ± 0.77 kg; P = .005), significantly less change in shoulder girth (P < .05), and a significantly lower immediate postoperative visual analog scale pain score (P = .036). At 1 year postoperatively, the differences between groups for American Shoulder and Elbow Surgeons, visual analog scale pain, and Single Assessment Numeric Evaluation were not significant (P > .2).

CONCLUSION

A hyperosmolar irrigation solution provides a safe and effective way to decrease periarticular fluid retention associated with arthroscopic rotator cuff surgery without any adverse long-term effects. Use of a hyperosmolar irrigation solution for shoulder arthroscopy has potential clinical benefits to surgeons and patients.

Clinical Safety of the 5 O'clock Portal in Shoulder Arthroscopy: A Prospective Study

Background

The present study aimed to determine the rate of clinically significant neurovascular complications associated with the routine use of the 5 o'clock portal during arthroscopic Bankart repair.

Methods

Forty-eight consecutive patients underwent arthroscopic Bankart repair with the use of the 5 o'clock portal. These patients were followed at 2 weeks and 6 weeks postoperatively for subjective signs of neurovascular injury (i.e. numbness and tingling) as well as objective signs (i.e. intraoperative bleeding, radial pulse, capillary refill, sensation, motor strength, haematoma and oedema).

Results

Two out of 48 patients (4.2%) experienced transient neurological symptoms in an ulnar nerve distribution, which resolved by 6 weeks. There was no occurrence of clinically significant injury to the axillary nerve, axillary artery, musculocutaneous nerve, lateral cord of the brachial plexus or cephalic vein.

Conclusions

No clinically detectable neurovascular injuries were associated with the use of the 5 o'clock shoulder portal during Bankart repair.

Osteochondral Allografts in Shoulder Surgical Procedures

The use of fresh osteochondral allografts has become popular in many joint-preserving orthopaedic procedures and shows early promising results within the shoulder. Distal tibial allograft contains a stout cartilaginous layer that appears to have highly congruent curvature and concavity to the glenoid, which makes for an optimal allograft option for instability. In the setting of large Hill-Sachs lesions, the use of a humeral-head osteochondral allograft is essential to restore geometry, stability, and mechanics of the native glenohumeral joint. One must be cautious with the treatment of glenoid chondral lesions with osteoarticular grafting procedures because of the depth of the glenoid compared with the depth of subchondral bone on the graft necessary to achieve a press fit, and advanced imaging is recommended when planning an operative intervention. Optimizing joint-preservation treatment with osteochondral allografts will rely on the long-term results of these procedures, and careful patient selection, preoperative discussion, and realistic expectations are necessary.

Hyperosmolar irrigation compared with a standard solution in a canine shoulder arthroscopy model

BACKGROUND

A hyperosmolar irrigation solution may decrease fluid extravasation during arthroscopic procedures. Demonstrating the safety of a hyperosmolar irrigation solution with respect to chondrocyte viability and cartilage water content was deemed necessary before designing a clinical efficacy study.

METHODS

We designed a translational animal model study in which hyperosmolar arthroscopy irrigation fluid (1.8%, 600 mOsm/L) was compared with normal saline (0.9%, 300 mOsm/L). Purpose-bred research dogs (n = 5) underwent bilateral shoulder arthroscopy. Irrigation fluid was delivered to each shoulder joint (n = 10) at 40 mm Hg for 120 minutes using standard ingress and egress portals. The percentage change in shoulder girth was documented at the completion of 120 minutes. Articular cartilage sections from the glenoid and humeral head were harvested from both shoulders. Chondrocyte viability and tissue water content were evaluated. Differences between groups and compared with time 0 controls were determined, with significance set at P <.05.

RESULTS

The mean percentage change in shoulder girth was higher in the isotonic control group (13.3%) than in the hyperosmolar group (10.4%). Chondrocyte viability and tissue water content for glenoid and humeral head cartilage were well maintained in both treatment groups, and differences were not statistically significant.

CONCLUSIONS

The data from this study suggest that doubling the osmolarity of the standard irrigation solution used for arthroscopy was not associated with any detrimental effects on chondrocyte viability or tissue water content after 2 hours of arthroscopic irrigation. On the basis of potential benefits in conjunction with the safety demonstrated in these data, clinical evaluation of a hyperosmolar solution for irrigation during shoulder arthroscopy appears warranted.

Complications of arthroscopic shoulder surgery

Shoulder arthroscopic procedures have become common in today's orthopedic practice. The safety of shoulder arthroscopy though well established, is not without complications both minor and significant. The true incidence of complications is difficult to identify in the current literature. However, as with all procedures, complications associated with shoulder arthroscopy do occur. General complications (ie, infection), those specific to shoulder arthroscopy (ie, positioning) and those associated with specific procedures (ie, failure) all have been recognized. The purpose of this article is to review the current literature regarding complications in shoulder arthroscopy, provide insight into the risk factors and types of complications and to provide guidelines on the prevention and management of complications if and when they occur.

30-day morbidity and mortality after elective shoulder arthroscopy: a review of 9410 cases

BACKGROUND

Few studies have reported incidence of or risk factors for morbidity and mortality after elective shoulder arthroscopy.

METHODS

We used Current Procedural Terminology (CPT) billing codes to query the National Surgical Quality Improvement Program database and identified 9410 cases of elective shoulder arthroscopy. Univariate and multivariate analyses were used to identify risk factors for complication.

RESULTS

Among 9410 patients, 109 complications occurred in 93 (0.99%). Major morbidity was 0.54% (51 patients), which included 4 patients (0.04%) with a mortality, and minor morbidity was 0.44% (42 patients). The most common complication was a return to the operating room (29 cases, 0.31%). Superficial surgical site infections occurred in 15 cases (0.16%), deep infections in 1 (0.01%), deep venous thrombosis or thrombophlebitis in 8 (0.09%), peripheral nerve injury in 1 (0.01%), and pulmonary embolism in 6 (0.06%). The multivariate analysis showed smoking history (odds ratio [OR], 1.91; 95% confidence interval [CI], 1.12-3.27), history of chronic obstructive pulmonary disease (OR, 3.25; 94% CI, 1.38-7.66), operative time of longer than 1.5 hours (OR, 2.1; 95% CI, 1.32-3.36), and American Society of Anesthesia class of 3 or 4 compared with 1 or 2 (OR, 1.82; 95% CI, 1.03-3.21) as risk factors for complication.

CONCLUSIONS

Morbidity and mortality are rare events after elective shoulder arthroscopy, and the procedure should generally be considered safe. Surgeons should offer smoking cessation to active users of tobacco and should be efficient with operative time whenever possible.

LEVEL OF EVIDENCE

Level II, prospective cohort design, treatment study.

Techniques for suture anchor removal in shoulder surgery

Although suture anchor complications after arthroscopic shoulder surgery are uncommon, they can be devastating, such as articular cartilage or bone loss secondary to a dislodged or prominent suture anchor. Proper insertion of the anchor is the most important factor in the prevention of this complication, but if a complication occurs, prompt recognition and treatment are important to prevent damage to the shoulder. The goals were to (1) discuss strategies for preventing or dealing with dislodged or prominent suture anchors and (2) introduce techniques for removal of these implants.

Complications in shoulder arthroscopy

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

The role of arthroscopy in the revision of failed Latarjet procedures

Glenohumeral instability is an intrinsic pathological condition of the shoulder, owing to its ample range of mobility that predisposes this joint to a somewhat limited degree of stability. Several techniques have been employed for the treatment of instability. Among these, one is the Latarjet procedure, recommended for cases of substantial bone deficit on the humeral head or on the anterior region of the glenoid. Such technique gives generally good, long-term results, considering the low incidence of recurrence. However, potential complications such as glenohumeral arthrosis, absorption of the bone block, breakage, malpositioning or mobilization of the screws, infections, neurological or vascular complications can be serious. Moreover, as a result of further severe trauma, the shoulder can become again globally unstable. In such cases, the question arises of which technique to employ in surgical revision, since the Latarjet procedure determines substantial subversion of glenohumeral anatomy. The aim of the study was the analysis of arthroscopical treatment after failure of a Latarjet procedure and to describe the related definitive results. During the period between January 2000 and June 2007, we treated 17 patients (18 shoulders) using arthroscopy, following failure of an open Latarjet surgical procedure. One patient was operated bilaterally. Clinical revision according to the Constant Score, ROWE, ASES, UCLA and the VAS scale for pain evaluation was carried out during follow-up examination after an average period of 5 years and 9 months (min. 2 years-max. 9 years) from latest surgery. The system of evaluation according to the Constant Score indicated an average score of 78.4/100 at follow-up examination; UCLA indicated 27.2/35; ASES 99.6/120; ROWE 75.2/100. With regard to pain, the VAS Scale indicated an average score of 2.9/10. As criteria for relapse, we considered classic cases of dislocation and subluxations, or sprains with subluxation, and subjectively experienced apprehension and pain to a degree that seriously inhibited the patient's daily life. The incidence of relapse following the final surgical operation (taking into consideration both frank dislocations and subluxations) was 16.7%. At clinical revision, one patient showed dislocation due to relatively modest trauma approximately 1 year following the second surgery (5.6%). Episodes of subluxation or sprains continued in 2 shoulders (11.1% relapse). In 11 cases (61%), return to sports activities was achieved. Arthroscopy technique using anchors and sutures can, in selected cases, lead to satisfactory results, allowing, by means of minimal surgical invasion, identification and treatment also of intra-articular lesions, where associated.

Arthroscopic removal of proud metallic suture anchors after Bankart repair

INTRODUCTION

This study presents an arthroscopic removal technique for proud metallic suture anchor after Bankart repair and analyzes the cause of anchor failures.

PATIENTS

Six male patients with an average age 23 years who had proud anchor on the glenoid surface were included. The diagnosis of six patients at the time of the primary surgery was traumatic anterior shoulder instability. Four patients had arthroscopic repair and two had open Bankart repair previously. Four patients complained of pain accompanying a metallic clicking sound during shoulder motion which increased with abduction and external rotation. One patient had pain with apprehension of dislocation and another patient suffered from only pain. Most symptoms had been revealed during the rehabilitation period (average 8.3 months) and confused with postoperative pain. The protruded anchors were detected through plain radiographs in four patients and during arthroscopic examination in two patients.

METHOD

To extract the proud anchor arthroscopically, a screw driver of a larger diameter than that of the proud suture anchor was used to retrieve the anchor. A larger screw driver was striked with a hammer along the previous suture anchor hole to make a room between the suture anchor and the adjacent glenoid bone so that the hole of the suture anchor became larger. After the hole was widened, the suture anchor had enough room to move freely and it could be removed with a grasper or a mosquito easily. The location of the proud anchor was 2, 3 and 5 o'clock in three patients and 4 o'clock in three patients. In two patients, the suture anchor was malpositioned about 5 mm medial from the anterior glenoid rim. All patients had chondral damage on the humeral head.

RESULTS

Following the procedure none had shoulder instability in 3 years of follow-up. Preoperative visual analog scale score for pain was an average of 3.5. The visual analog scale score for pain was decreased to 1.2 after surgery. All patients had a slight limitation of external rotation preoperatively, and they showed a normal range of motion postoperatively. Constant score improved from 65 to 89, and similarly, American Shoulder and Elbow Society score increased from 67 to 88 after the operation.

CONCLUSION

Despite small numbers of patients, a successful removal of proud metal suture anchors was achieved using a large empty suture anchor screw driver, which is a simple and reproducible method to remove a proud metallic suture anchor arthroscopically.

Complications associated with anterior shoulder instability repair

Anterior shoulder instability is a common orthopaedic problem, and the surgical treatment, both open and arthroscopic, has been shown to effectively restore stability and prevent recurrence. However, despite success with these surgical techniques, there are several clinically relevant complications associated with both open and arthroscopic techniques for anterior shoulder stabilization. These complications can be subdivided into preoperative, intraoperative, and postoperative and include entities such as nerve injury, chondrolysis, incomplete treatment of associated lesions, and subscapularis dysfunction. When they occur, complications may significantly impact patient outcomes and function. Therefore, surgeon awareness and identification of the factors associated with these complications may help prevent occurrence. Although failure of instability repair can be classified as a complication of surgery, it requires an entirely separate discussion and is therefore not addressed in this article. Because most of the previously published studies on anterior shoulder instability have emphasized surgical technique and clinical outcomes, the purpose of this article is to define the complications associated with anterior instability repair and provide recommendations on techniques that may be used to help avoid them.

Complex shoulder disorders: evaluation and treatment

Evaluation of patients with shoulder disorders often presents challenges. Among the most troublesome are revision surgery in patients with massive rotator cuff tear, atraumatic shoulder instability, revision arthroscopic stabilization surgery, adhesive capsulitis, and bicipital and subscapularis injuries. Determining functional status is critical before considering surgical options in the patient with massive rotator cuff tear. When nonsurgical treatment of atraumatic shoulder stability is not effective, inferior capsular shift is the treatment of choice. Arthroscopic revision of failed arthroscopic shoulder stabilization procedures may be undertaken when bone and tissue quality are good. Arthroscopic release is indicated when idiopathic adhesive capsulitis does not respond to nonsurgical treatment; however, results of both nonsurgical and surgical treatment of posttraumatic and postoperative adhesive capsulitis are often disappointing. Patients not motivated to perform the necessary postoperative therapy following subscapularis repair are best treated with arthroscopic débridement and biceps tenotomy.

Indwelling interscalene catheter use in an outpatient setting for shoulder surgery: technique, efficacy, and complications

Indwelling interscalene catheters are utilized for inpatient postoperative pain control after shoulder surgery. Improved medical equipment and advanced techniques may allow safe and efficacious outpatient use. One hundred and forty-four consecutive indwelling interscalene catheter placements were reviewed to determine adverse events, complications, and efficacy. Real-time ultrasound-guided catheter placement technique is described. Post-anesthesia care unit (PACU) narcotic consumption and last recorded pain score were reviewed to gauge efficacy. The catheter placement technique was 98% successful. There were 14 (9.7%) minor adverse events including inadequate analgesia (8), accidental catheter removal (4) of disconnection (1), and shortness of breath (1). The single complication (0.7%) was a small apical pneumothorax. The average PACU narcotic consumption in intravenous morphine equivalents was 1.7 mg. The average last recorded PACU pain score on a scale of 1 to 10 was 0.6. Catheter placement under real-time ultrasound guidance is accurate. Outpatient use of indwelling interscalene catheters is safe and efficacious.

Immediate postoperative fluid retention and weight gain after shoulder arthroscopy

PURPOSE

The primary purpose of this study was to determine the amount of weight gain immediately after shoulder arthroscopy. In addition, patient and surgical factors correlated with weight gain were analyzed. We hypothesized that there would be a significant increase in weight immediately after shoulder arthroscopy and that the amount of weight gain would correlate with a number of surgical factors.

TYPE OF STUDY

Observational case series.

METHODS

Fifty-three patients were enrolled in the study. There were 34 male and 19 female patients, with a mean age of 47.1 +/- 13.8 years. All patients were weighed before and after surgery using the same weight scale by the same observer. Weight gain was calculated and adjusted to account for the weight of the dressing and sling. Weight gain then was correlated to various clinical and surgical variables. Pearson correlation coefficients, Student t tests, and stepwise regression were used to determine significant correlations between clinical and surgical variables and weight gain.

RESULTS

The mean amount of net weight gain was 8.7 +/- 3.9 lb (range, 0.8-18.8 lb), representing 4.6% +/- 2.1% of preoperative weight. The mean amount of weight gain attributable to arthroscopy fluid only was 4.2 +/- 3.8 lb (range, 0-14.5 lb), representing a gain of 2.2% +/- 2.0% of preoperative weight. The mean amount of intravenous fluid infused was 1,885 +/- 547 mL, and the mean amount of normal saline arthroscopy fluid used was 30 +/- 24 L. Surgical time, the amount of arthroscopy fluid, the size of the rotator cuff tear, the number of tendons involved, the presence of a subscapularis tear, the number of procedures performed, the concomitant performance of a subacromial decompression, the number of BioCorkscrew (Arthrex, Inc., Naples, FL) anchors used, and the total number of anchors used all correlated with increasing weight gain (all P < .05). A procedure of stepwise regression selection did not identify any quantitative parameters attributable to weight gain other than the earlier-described parameters. There were no significant intraoperative or postoperative complications attributable to the amount of weight gain.

CONCLUSIONS

Weight gain immediately after shoulder arthroscopy is a common finding. Although no complications were seen in this group of patients, both patients and surgeons should be aware of this concern after shoulder arthroscopy and the potential complications related to it.

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

PURPOSE

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

TYPE OF STUDY

Anatomic cadaveric study.

METHODS

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

RESULTS

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

CONCLUSIONS

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

CLINICAL RELEVANCE

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

Interactive and interventional sports medicine imaging

The concepts and clinical potential of interactive magnetic resonance imaging (MRI) in which an examiner manipulates the joint of interest during MRI, and of interventional sports medicine imaging in which radiological guidance is used for targeted therapy of injuries and masses are described. As illustrated by a series of clinical cases, we believe that with further development, interactive MRI will play an important role in the comprehensive evaluation of patients with shoulder pain or dysfunction as well as other joint derangements. Interventional sports medicine takes advantage of the increasingly sophisticated diagnostic value of MRI and the radiologist's ability to use imaging to guide percutaneous therapy. We review our recent experience treating a wide variety of disorders such as cysts, hematomas, and inflammatory disorders, focusing on techniques utilizing ultrasound and MR guidance.

Anterior cruciate ligament thermal shrinkage

Heat has been used as a therapeutic form of treatment in the field of medicine since ancient times. Electrothermal energy delivered by radiofrequency has the advantages of being able to be used by even the casual arthroscopist and being relatively inexpensive. One of the expanded uses is treating ligament laxity, including the anterior cruciate.

Radiofrequency electrothermal shrinkage of the anterior cruciate ligament

The efficacy of electrothermal collagen shrinkage in the treatment of patients with anterior cruciate ligament laxity was evaluated. Eighteen patients who had continuity of the anterior cruciate ligament but had symptomatic laxity were treated with arthroscopic electrothermal shrinkage of the anterior cruciate ligament using a monopolar radiofrequency probe. The mean length of follow-up in patients whose stability was maintained was 20.5 months. Seven of the patients had undergone previous reconstruction, four with patellar tendon graft and three with quadrupled hamstring tendon graft. Laxity was chronic in nine patients and acute in nine. The KT-1000 arthrometer results at 1 month postoperatively revealed decreased anterior excursion, with an average side-to-side difference of 1.9 mm. However, 11 patients had a failed result at an average 4.0 months. Of the seven patients with successful results, six had native ligaments and had been treated for acute laxity and one had a patellar tendon graft and had been treated for chronic laxity. Even with the short-term follow-up in our study, it is evident that thermal shrinkage using radiofrequency technology has limited application for patients with anterior cruciate ligament laxity. Although it may be useful in treating patients with an acutely injured native anterior cruciate ligament, further study is needed to see if the ligament stretches out over time or is at increased risk of reinjury.

Complications associated with arthroscopic shoulder surgery

We review the literature on complication of arthroscopic shoulder surgery and their management. Computer data based searches were used to identify articles regarding complications of shoulder arthroscopy, as well as hand searches of Arthroscopy and Journal of Shoulder and Elbow Surgery over the last decade. Arthroscopic shoulder surgery has become a popular therapeutic and diagnostic procedure during the past two decades. As with all interventions complications can occur which require recognition and management by the orthopedic surgeon. While the literature is helpful with identifying types of complications, establishing the rate of these complications remains elusive. These complications can be divided into general complications, complications generic to all shoulder procedures, and complications specific to the type of procedure performed. General complications such as infection and anesthesia problems continue to show low incidences. Shoulder arthroscopy presents increased risk of complications over knee arthroscopy in regard to vascular and neurologic injury, fluid extravasation, stiffness, iatrogenic tendon injury, and equipment failure. New techniques of increased complexity for subacromial surgery, rotator cuff repair, and arthroscopic instability present new problems related to implant failure, nerve injury, iatrogenic fracture, and capsular necrosis. While the rate of complications especially with newer procedures remain elusive, most studies suggest that the rate is low, 5.8-9.5% in all recent review studies published. Underreporting complications makes assessment of incidence rates of complication difficult. Proper patient selection, attention to operative detail, and careful post-operative monitoring can minimize the morbidity associated with these complications.

Thermal capsular shrinkage: Basic science and clinical applications

Recently, the use of thermal energy to shrink the redundant glenohumeral joint capsule in patients with instability has generated a great deal of interest. Proponents assert that the procedure avoids the need for an open stabilization and it may be used as an adjunct to an open or arthroscopic capsulolabral repair. The use of nonablative thermal energy to shrink soft-tissue collagen appears to induce ultra-structural and mechanical changes at or above 60 degrees C. The microscopic changes reflect the unwinding of the collagen triple helix and loss of the fiber orientation. The fibrils contract into a shortened state and reactive fibroblasts have been shown to grow into this treated area and synthesize the collagen matrix. The biomechanical properties of the tissue do not appear to be detrimentally altered if shrinkage is limited to less than 15% and if ablation or excess focal treatment is avoided. The endpoint of optimal shrinkage is not known and clinical estimations of tissue changes and volumetric reduction are used as guides to treatment. The first clinical follow-up study was only recently published in the peer-reviewed literature and prior preliminary reports were optimistic regarding the use of thermal energy for the treatment of glenohumeral instability. Thermal capsular shrinkage has been used as an adjunct to a capsulolabral repair, as well as an isolated treatment for the disorders of internal impingement and multidirectional instability. Additional evaluation is necessary to determine the optimal quantity of energy needed for tissue shrinkage without inadvertent tissue destruction. The long-term clinical effect, mechanical properties, and durability of the newly produced collagen need to be analyzed further. The basic science and clinical applications of this newly applied technology are reviewed in this article.

Hemoptysis due to migration of a fractured Kirschner wire

We report a rare complication related to the insertion of Kirschner wires for stabilization of an acromioclavicular separation. Five years after placement of the Kirschner wires, the patient presented with hemoptysis. On review of chest radiographs, a fractured wire was found to have migrated from the acromioclavicular joint, through the hemithorax and into the trachea.