FOOT AND ANKLE

ORTHOPEDICS August 2011;34(8):356.

Comparison of MRI and Arthroscopy in Modified MOCART Scoring System After Autologous Chondrocyte Implantation for Osteochondral Lesion of the Talus

by Kyung Tai Lee, MD; Yun Sun Choi, MD; Young Koo Lee, MD; Seung Do Cha, MD; Hyung Mo Koo, MD

DOI: 10.3928/01477447-20110627-10

Abstract

Magnetic resonance imaging (MRI) and arthroscopy have frequently been used to evaluate articular cartilage. Many studies have compared the accuracy of MRI to that of arthroscopy. However, there have been no previous comparison studies between MRI and arthroscopy in the evaluation of repaired cartilage after autologous chondrocyte implantation using the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) scoring system. The purpose of this study was to compare the results between MRI and arthroscopy after autologous chondrocyte implantation of an osteochondral lesion of the talus using a modified MOCART scoring system.

Our study investigated 27 consecutive cases in 26 patients who underwent follow-up MRI and second-look arthroscopy 1 year following autologous chondrocyte implantation based on their osteochondral lesion of the talus diagnosis. According to the comparison results of those 5 categories, the agreement between MRI and arthroscopy evaluation results was statistically significant with good reliability in the categories of the degree of defect repair and defect filling, the quality of repaired tissue surface, and synovitis. However, the integration with the border zone and the adhesion category showed poor to moderate reliability. There has been no well-established correlation method between arthroscopy and MRI after autologous chondrocyte implantation of an osteochondral lesion of the talus.

Dr Lee (Kyung Tai) is from the Foot and Ankle Clinic, KT Lee’s Orthopedic Hospital, Dr Choi is from the Department of Radiology, Eulji Hospital, Eulji University School of Medicine, Seoul, Drs Lee (Young Koo) and Koo are from the Department of Orthopedic Surgery, Soonchunhyang University, Bucheon Hospital, Gyeonggi-Do, and Dr Cha is from the Department of Orthopedic Surgery, Kwandong University Hwajung dong, Dukyang-Gu, Koyang-Si, Gyeonggi-Do, Republic of Korea.

Drs Lee (Kyung Tai), Choi, Lee (Young Koo), Cha, and Koo have no relevant financial relationships to disclose.

Correspondence should be addressed to: Young Koo Lee, MD, Department of Orthopedic Surgery, Soonchunhyang University 4 Jung-Dong, Wonmi-Gu, Bucheon-Si, Gyeonggi-Do, 420-767, Republic of Korea (brain0808@hanmail.net).

Posted Online: August 08, 2011

Magnetic resonance imaging (MRI) and arthroscopy frequently have been used to evaluate articular cartilage. ^1,2 Many studies have compared the accuracy of MRI to that of arthroscopy. With regard to the knee joint, O’Connor et al ³ reported the accuracy of MRI compared to arthroscopy for osteochondritis dissecans was 85%. For the ankle joint, Mintz et al ² reported the accuracy of MRI of osteochondral lesions of the talus was 83% and Lee et al ¹ reported an accuracy of 81%. However, none of the prior studies were based on the evaluation results of repaired cartilage after autologous chondrocyte implantation of an osteochondral lesion of the talus.

In addition, there have been no previous comparison studies between MRI and arthroscopy in the evaluation of repaired cartilage after autologous chondrocyte implantation using the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) scoring system. The MOCART scoring system is an evaluation method for repaired cartilage with low interobserver variability. ⁴ It is a useful method for long-term follow-up as it is based on a scoring system. ⁵ However, previous MOCART-based studies have dealt only with the knee joint; none of the MOCART studies have examined the ankle joint. The purpose of this study was to compare the results between MRI and arthroscopy after autologous chondrocyte implantation of an osteochondral lesion of the talus using a modified MOCART scoring system.

Materials and Methods

This study was performed from September 2005 to March 2008 and included 27 cases in 26 consecutive patients who received a follow-up MRI and second-look arthroscopy 1 year after autologous chondrocyte implantation caused by an osteochondral lesion of the talus. Average patient age was 33.9 years (range, 16–56 years), and the study population comprised 19 men and 7 women. A total of 13 right and 14 left ankles were examined. The study was approved by our Institutional Research Board, and all study participants provided informed consent prior to study enrollment.

All patients were diagnosed based on MRI and physical examinations, and the diagnosis was confirmed during surgery using arthroscopy. Approximately 1 year following their initial surgery, patients underwent MRI and second-look arthroscopy. A modified MOCART scoring system was used to classify MRI and arthroscopy evaluation of the osteochondral lesion of the talus. Five categories of the MOCART scoring system that could be applied to both MRI and arthroscopy were used with some modification to compare the results of the 1-year follow-up MRI and second-look arthroscopy (Table 1).

Modified MOCART Scoring System for the Evaluation of Autologous Chondrocyte Implantation

Surgical Technique

During the first surgical stage, a cartilage biopsy was performed after a local anesthesia block was administered to the foot and ankle. Autologous chondrocyte implantation, the second-stage surgery, was performed under spinal anesthesia, with patients placed in a frog-leg position. An incision was made along the midline of the medial malleolous, which exposed approximately 10 cm of the posterior tibial tendon and anterior ankle joint. Oblique medial malleolar osteotomy was performed under fluoroscopy.

The osteochondral lesion of the talus then was exposed by retracting the distal malleolar fragment. The lesion was removed, and a 2.5-mm drill was used to prevent delamination of the gel matrix. The area was injected with Chondron (Sewoncellontech Corp, Seoul, Korea), which hardened within 5 minutes given its properties to convert the fibrin-mixed chondrocyte liquid mixture into the gel matrix within the lesion. Through a pre-drilled hole, the osteotomy site was fixed using a 4.5-mm diameter cannulated screw and a K-wire without a rotational deformation. The ankle was immobilized at 90° using a plaster splint, and nonweight-bearing measures were initiated.

The third-stage surgery was performed under spinal anesthesia. Patients were placed in a kneeling position to retract the ankle using an 8-lb weight to check the joint condition through the anteromedial and anterolateral portals. Patients then were placed in a supine position with their legs on the table, and the previous incision scar was incised to remove the screw.

Imaging Technique

Magnetic resonance imaging was performed 1 year postoperatively using a 1.5-Tesla unit (Twinspeed; General Electric Health Care, Milwaukee, Wisconsin) and an extremity coil. Sagittal inversion recovery images were obtained with a 16-cm field of view, repetition time of 5000 milliseconds, echo time of 16 ms, inversion time of 150 milliseconds, echo train length 8, and slice thickness of 3.5 mm with no interslice gap. Sagittal, axial, and coronal intermediate-weighted fast-spin echo images were obtained with a repetition time of 4000 milliseconds, effective echo time of 25 to 26 milliseconds, echo train length 8, slice thickness of 3 mm with no inter-slice gap, and field view of 11 to 15 cm. A matrix of 512×256 was obtained with a number of excitations of 1 to 2. Coronal fat-suppressed 3-dimensional spoiled gradient-recalled images were added with a 12-cm field of view, repetition time of 40 milliseconds, echo time of 6 milliseconds, flip angle of 40°, slice thickness of 1.5 mm with no interslice gap, and matrix of 256×192. An experienced musculoskeletal radiologist assessed all MRIs and was unaware of the second-look arthroscopic findings.

Statistical Analysis

Statistical analysis was performed using the modified MOCART scoring system under the hypothesis that there is no difference between MRI and arthroscopy and under the alternative hypothesis that there is a difference between MRI and arthroscopy, to determine any difference between MRI and arthroscopy. To assess agreement and reliability, the intraclass correlation coefficients (ICC) were obtained from random effects 1-way analysis of variance. Intraclass correlation coefficient values close to zero indicated no interrater reliability, and ICC values close to 1 indicated perfect reliability. All analyses were performed using SPSS version 12.0 (SPSS Institute, Chicago, Illinois), and all significance tests were 2-tailed. For all tests, a P value of <.05 was considered statistically significant.

Results

Among the 5 categories of the MO-CART scoring system that are applicable to both second-look arthroscopy and MRI, the degree of defect repair and filling of the defect category (Table 2) showed congruent results in 16 of 27 cases. Of the 14 cases in which arthroscopy showed complete manifestations, MRI showed complete manifestations in 12 cases (Figure 1) and >50% of the adjacent cartilage filling manifestations in 2 cases. However, in 5 cases in which arthroscopy showed <50% of the adjacent cartilage filling, MRI showed >50%, indicating complete disagreement. Therefore, the degree of defect repair and filling of the defect category showed a relatively high correlation, resulting in an ICC value of 0.7222 ( P<.0001).

Degree of Defect Repair and Filling Category

Coronal (A) and sagittal (B) intermediate-weighted fast-spin echo MRIs of a 16-year-old girl 1 year after autologous chondrocyte implantation of the medial talar dome show complete filling of the defect of the osteochondral lesion (white arrows) and complete integration. The repaired tissue surface is relatively smooth and synovitis (black arrows) is seen. Arthroscopic photograph shows complete defect filling with a smooth surface over the talus. In this case, MRI demonstrates a good correlation with arthroscopy (C).

In the integration into the border zone category (Table 3), arthroscopy showed complete manifestations in 18 cases; MRI results were in agreement in 17 cases, with 1 case displaying a demarcating border. Nevertheless, of the 5 cases in which arthroscopy showed visible integration defects, MRI displayed incongruent results in 3 cases (Figure 2). Therefore, in this category, there was a tendency to disagree, with an ICC value of 0.48 ( P=.0034).

Integration Into the Border Zone

Sagittal (A) and coronal (B) intermediate-weighted fast-spin echo and coronal fat-suppressed 3D-spoiled gradient-recalled MRIs (C) of a 39-year-old woman show complete filling of the defect (arrows) of the osteochondral lesion of talus and complete integration. The repaired tissue shows damaged surface with fibrillation. Arthroscopic photograph shows complete filling of the defect with fibrillation of the surface but incomplete integration (arrow), which reveals disagreement with the MRI findings (D).

For the surface of the repaired tissue category (Table 4), the results were in agreement in 24 of 27 cases (Figure 3), with an ICC value of 0.8523 ( P<.0001). In the adhesion category (Table 5), MRI failed to detect any adhesions, whereas arthroscopy showed adhesion in 2 cases. Therefore, there was complete disagreement in the adhesion category, with an ICC of 0.00 ( P=.50). Finally, with regard to the synovitis category (Table 6), MRI and arthroscopy agreed in 24 of 27 cases, showing a fairly high degree of agreement and an ICC value of 0.7797 ( P<.0001).

Surface of the Repaired Tissue

Sagittal (A) and coronal (B) intermediate-weighted fast-spin echo MRIs of a 28-year-old man show complete filling of the defect of the osteochondral lesion of the medial talar dome. The repaired tissue shows damaged surface (arrows) with ulcer and fibrillation. Arthroscopic photograph shows complete defect filling and the surface of repaired tissue is damaged. In this case, MRI demonstrates a good correlation with arthroscopy (C).

Adhesion

Synovitis

Among the 5 categories, arthroscopy and MRI showed a high degree of agreement, producing ICC values with good reliability in the categories of degree of defect repair and filling, surface of the repair tissue, and synovitis. However, moderate to poor reliability was noted with respect to the categories of integration into the border zone and adhesion, suggesting that there might be some limitations to using these categories. In addition, the adhesion category showed complete disagreement, with an ICC value of 0.00 (Table 7).

Statistical Analysis Results

Discussion

Articular cartilage represents the most easily injured portion of a joint for which there is still no completely established treatment. There are various treatment methods for articular cartilage injury, the first being a primary repair technique in patients with acute symptoms ⁶ and attempted lavage and debridement in patients with chronic symptoms. ^7,8 Marrow-inducing repair techniques are widely used, although they have low biomechanical properties as cartilage is formed by fibrous cartilage. ⁹Restorative techniques recently have attracted attention as the cartilage is formed by hyaline cartilage restored to the mechanical properties of an uninjured normal cartilage. Our study technique also was used in patients with articular cartilage injury who underwent autologous chondrocyte implantation using restorative techniques.

Regarding patients who underwent various types of surgery, we compared the MRI and arthroscopy results. ^3,9 Although Mintz et al ² reported that the accuracy of MRI for osteochondral lesions of the talus was 83%, this report was not used in the postautologous chondrocyte implantation outcome. To address the increased need for such an outcome, Marlovits et al ¹⁰ reported the MOCART scoring system in 2004. The MOCART scoring system gradually developed for high-resolution MRI with the intent of defining pertinent variables for an objective description of repaired tissue, given the current technological limitations. Since Marlovits’ study, multiple articles have been published reporting the use of the MOCART scoring system, suggesting it is a useful method for long-term follow-up using point scales. ⁵

Recent articles also have highlighted the accuracy of MOCART for evaluating repaired knee cartilage after surgery for osteochondritis dissecans producing assessments with low interobserver variability. ⁴However, previous articles primarily addressed knee evaluations, prompting the need for evaluation studies on osteochondral lesions of the talus. In our study, the MOCART scoring system was modified (Table 1) by excluding the status of the subchondral lamina injured by drilling from the original MO-CART scoring system. In the arthroscopic fields, not only the structure of repaired tissue but also their signal characteristics, as shown in Table 1, could not be evaluated.

In our study, the categories for the degree of the defect repair and filling, surface of the repair tissue, and synovitis all showed fairly high ICC results. However, the categories of integration and adhesion showed low ICC. Although Mintz et al ² reported that the accuracy of MRI for osteochondral lesions of the talus was 83%, the report was not based on the results after autologous chondrocyte implantation. Therefore, an evaluation using the MO-CART scoring system was performed to verify accuracy.

According to the results of our study, the integration and adhesion category showed a low ICC, which was an unexpected result. A possible reason for this finding may be because the ankle cartilage is one-third thinner than knee joint cartilage ¹¹ and the articular surfaces of the ankle are naturally closely packed and congruous, unlike the knee where the joint surfaces are not congruent and there is no clear separation of the articular surfaces of the tibiotalar joint. As a result, ankle cartilage is hardly ever evaluated using MRI, in contrast to knee cartilage. It may be necessary to consider new isotropic MRI techniques at a high field (3T) MRI with a dedicated multichannel coil that potentially improves evaluation of repair tissue in the anatomically challenging ankle joint. ¹²

Furthermore, the adhesion category in our study showed complete disagreement, possibly due to one of the postautologous chondrocyte implantation complications where routine MRI may be limited in distinguishing adhesion from a closely packed joint with thin cartilage. In addition, compared to the results reported by Mintz et al, ² the MOCART scoring system is much more subdivided than in their study. Consequently, there will be some limitations in correlating arthroscopy and MRI after autologous chondrocyte implantation using those subtypes, which would be better used as an alternative method for following long-term clinical outcomes.

This study has limitations in that we studied relatively few cases and did not include all subtypes of the MOCART scoring system. Our results suggest further studies with more cases are needed. In addition, if modifications of the procedure or advancements in techniques allow for the study of the rest of the MOCART scoring system subtypes not included in this study because of the surgical procedure performed, more accurate data may be obtained in the future.

Conclusion

According to this comparison study between arthroscopy and MRI using the modified MOCART scoring system after autologous chondrocyte implantation in osteochondral lesion of the talus cases, the categories of degree of defect repair and filling, surface of the repair tissue, and synovitis all showed high ICC results, whereas the categories of integration into the border zone and adhesion showed low ICC values. There has been no well-established correlation method between arthroscopy and MRI after autologous chondrocyte implantation for osteochondral lesions of the talus. Although MRI allows for noninvasive evaluation of the repair tissue, limitations remain in using the MOCART scoring system to evaluate repaired cartilage after autologous chondrocyte implantation for osteochondral lesions of the talus.

For further information: http://www.orthosupersite.com/view.aspx?rid=86269

Medscape Medical News from the:

• American Orthopaedic Society for Sports Medicine (AOSSM) 2011 Annual Meeting

This coverage is not sanctioned by, nor a part of, the American Orthopaedic Society for Sports Medicine.

From Medscape Medical News

NSAID Shots Better Than Cortisone for Shoulder Pain

Nancy A. Melville

July 15, 2011 (San Diego, California) — A single injection of the nonsteroidal anti-inflammatory drug (NSAID) ketorolac shows superiority over corticosteroid injections in the treatment of shoulder impingement syndrome, according to a double-blind, randomized study presented here at the American Orthopaedic Society for Sports Medicine (AOSSM) 2011 Annual Meeting.

Corticosteroid injections are a common treatment for subacromial impingement syndrome; however, they are associated with some adverse effects, including tendon rupture, subcutaneous atrophy, and changes to articular cartilage. Previous research has shown, meanwhile, that NSAID injections also have efficacy in treating such patients.

In an effort to compare the 2 treatment approaches, researchers enrolled 48 patients diagnosed with isolated external shoulder impingement syndrome.

The patients were randomly assigned to receive either a single injection of 6 cc of 1% lidocaine with epinephrine and 40 mg triamcinolone or 6 cc of 1% lidocaine with epinephrine and 60 mg ketorolac.

Improvement was assessed according to the University of California– Los Angeles Shoulder Assessment Score, and the results at a 4-week follow-up visit showed that patients in both treatment groups had increased range of motion and decreased pain.

The mean improvement in the assessment score for the NSAID group, however, was 7.15 compared with just 2.13 in the steroid group (P = .03).

The NSAID group showed an increase in forward flexion strength (NSAID, 0.26; steroid, −0.07; P = .04) and improved patient satisfaction over the steroid group.

"These results demonstrate that both groups had good immediate response. However, only the NSAID group had a sustained response," said lead author Kyong Su Min, MD, from the Madigan Healthcare System in Tacoma, Washington.

"Two clinically important and pertinent advantages of NSAID injections are that there is no reported tissue atrophy or cartilage damage with NSAID injections, and the injections are not limited by frequency," he added.

The relief provided by the subacromial injection of both ketorolac and triamcinolone is believed to result from the drugs' local anti-inflammatory effect, he noted.

Ketorolac injections are often used in settings such as college athletics because of their robust pain-relieving properties, said Christian Lattermann, MD, an assistant professor of orthopaedic surgery and sports medicine from the University of Kentucky in Lexington.

"They are extremely powerful and have been used a lot in college sports as a pain medication because of their extremely strong anti-inflammatory effect," explained Dr. Lattermann, who is director of the university's Center for Cartilage Repair and Restoration Medical Center.

Although sparing patients some of the adverse effects of corticosteroid injections, however, the treatment is not without some adverse effects of its own, he cautioned.

"Ketorolac injections are not completely without side effects. They can cause bleeding, and you also have to make sure the kidneys are okay before using them, for instance. In addition, patients cannot take oral NSAIDs while they're receiving injections, so those are some down sides," he noted.

"If someone has a gastric ulcer, you shouldn't use it, and it's not entirely clear whether, in those high of doses, it is more or less detrimental to the rotary cuff than cortisone," Dr. Lattermann stated.

The study is valuable, however, in demonstrating ketorolac's potential efficacy in comparison to corticosteroid injections.

"I think it's a valid study and a very interesting idea and suggests ketorolac may be a useful alternative, particularly if corticosteroid treatment failed," Dr. Lattermann.

The study's authors and Dr. Lattermann have disclosed no relevant financial relationships.

American Orthopaedic Society for Sports Medicine (AOSSM) 2011 Annual Meeting: Abstract 34. Presented July 10, 2011.

For further information: http://www.medscape.com/viewarticle/746441?src=top10

HAND/UPPER EXTREMITY

ORTHOPEDICS July 2011;34(7):275.

Biomechanical Evaluation of Open Suture Anchor Fixation Versus Interference Screw for Biceps Tenodesis

by Derek F. Papp, MD; Nathan W. Skelley, BS; Edward G. Sutter, MS; Jong Hun Ji, MD; Carl H. Wierks, MD; Stephen M. Belkoff, PhD; Edward G. McFarland, MD

DOI: 10.3928/01477447-20110526-04

Abstract

Biceps tenodesis provides reliable pain relief for patients with biceps tendon abnormality. Previous cadaver studies have shown that, for biceps tenodesis, an interference screw provides biomechanical strength to failure superior to that of suture anchors. This finding has led some providers to conclude that screw fixation for biceps tenodesis is superior to suture anchor fixation. The purpose of the current study was to test the hypothesis that the strength of a 2-suture-anchor technique with closing of the transverse ligament is equal to that of interference screw fixation for biceps tenodesis.

In 6 paired, fresh-frozen cadaveric shoulder specimens, we excised the soft tissue except for the biceps tendon and the transverse ligament. We used 2 different methods for biceps tenodesis: (1) suture anchor repair with closing of the transverse ligament over the repair, and (2) interference screw fixation of the biceps tendon in the bicipital groove. Each specimen was preloaded with 5 N and then stretched to failure at 5 mm/sec on a materials testing machine. The load-to-failure forces of each method of fixation were recorded and compared. Mean loads to failure for the suture anchor and interference screw repairs were 263.2 N (95% confidence interval [CI], 221.7–304.6) and 159.4 N (95% CI, 118.4–200.5), respectively. Biceps tenodesis using suture anchors and closure of the transverse ligament provided superior load to failure than did interference screw fixation. This study shows that mini-open techniques using 2 anchors is a biomechanically comparable method to interference fixation for biceps tendon tenodesis.

Drs Papp, Ji, Wierks, Belkoff, and McFarland and Messrs Skelley and Sutter are from the Division of Shoulder Surgery and the International Center for Orthopedic Advancement, the Department of Orthopedic Surgery, The Johns Hopkins University/Johns Hopkins Bayview Medical Center, Baltimore, Maryland.

Drs Papp, Ji, Wierks, and Belkoff and Messrs Skelley and Sutter have no relevant financial relationships to disclose. Dr McFarland is a consultant for DePuy Mitek, Inc. The suture anchors and interference screws used in this study were donated by DePuy Mitek, Inc.

This article was awarded a 2011 Excellence in Medical Student Research Award, given by the Johns Hopkins School of Medicine.

Correspondence should be addressed to: Edward G. McFarland, MD, c/o Elaine P. Henze, BJ, ELS, Editorial Services, Department of Orthopedic Surgery, Johns Hopkins Bayview Medical Center, 4940 Eastern Ave, #A665, Baltimore, MD 21224-2780 (ehenze1@jhmi.edu).

Posted Online: July 07, 2011

The long head of the biceps tendon continues to generate interest in clinicians who treat shoulder pain. Controversy remains regarding the function of the long head of the biceps tendon, its role as a pain generator in the shoulder, and the most effective treatment for biceps abnormalities.

First, in terms of function, theories include the following: static stabilizer of the humeral head, ¹ static barrier to superior subluxation of the humeral head, ¹ dynamic stabilizer of the humeral head in an anterior-posterior direction in the abducted arm, ¹ and stabilizer of the humeral head in the throwing athlete when the arm is in abduction and external rotation. ² Second, several biceps tendon abnormalities, including tenosynovitis, ³ painful tendinopathy, ³ partial tears of the biceps tendon, ^3,4subluxations, ^3,4 dislocation of the biceps tendon, ³ and superior labrum lesions, ⁵ have been suggested as generators of pain in the shoulder. Third, treatment for symptomatic lesions of the long head of the biceps involves biceps tenotomy or tenodesis. Biceps tenotomy (via open or arthroscopic techniques) can relieve pain and restore function. ⁶

The literature describes numerous techniques for biceps tenodesis, including fixation of the tendon to the rotator cuff interval, ⁷ to the coracoids, ⁸ to the conjoint tendon, ⁹ to the intertubercular groove, ^4,10 to the proximal humerus beneath the bicipital groove, ^11–13 and to the greater tuberosity of the lateral humeral shaft. ⁸ The 3 major methods of fixation described for biceps tenodesis are a “keyhole” technique, ¹⁴ fixation with suture anchors, ³ or fixation with interference screws. ¹⁵

Previous studies have indicated that biceps tenodesis with interference screw fixation provides greater mechanical strength than that of suture anchor fixation. ^10,16 Yet at our institution, we routinely use and have good clinical results with 2 suture anchors for fixation of the biceps tendon into the bicipital groove with repair of the transverse ligament over the top of the tendon. The purpose of our study was to test the hypothesis that the strength of a 2-suture-anchor technique with closure of the transverse ligament is equal to that of interference screw fixation alone for tenodesis of the biceps tendon.

Materials and Methods

Biomechanical testing was performed using 6 paired, fresh-frozen cadaveric upper extremities obtained from the Maryland State Anatomy Board. The average age at death of the 4 female and 2 male donors was 70 years (range, 49–84 years). The limbs were thawed in the refrigerator for 24 hours before dissection. All shoulder joints were inspected for other major abnormalities, and all biceps tendons were carefully examined for partial tearing or other abnormalities. The rotator cuff was removed, and the tendon was released from the superior glenoid tubercle and the superior labrum. The transverse ligament was released at its midpoint to create a medial and lateral flap of the ligament. The intratubercular groove was examined for osteophytes and the intratubercular portion of the tendon was examined for any abnormality.

A tenodesis of the biceps tendons was performed with the tendon secured into the bicipital groove using 1 of 2 techniques, alternating between the right and left shoulders of matched pairs. In the first technique, we used a commercially available 7×23-mm absorbable interference screw (DePuy Mitek, Inc, Raynham, Massachusetts) designed for biceps tenodesis. To fix the biceps tendon into the bicipital groove, a hole was drilled in the inferior third of the bicipital groove for the tendon to be placed. On the proximal end of the tendon, the tendon was doubled over and sutured to itself with a number-5 Ticron (Tyco, Waltham, Massachusetts) Krackow stitch. ¹⁷ This reinforced end was pulled into the tunnel using a Beath needle and a 2-0 Ticron stitch, and the interference screw was placed using the technique described by Boileau et al. ¹⁵

For the suture anchor technique of biceps tenodesis, we placed 2 absorbable suture anchors into the bicipital groove, with the inferior anchor placed in the area of the bicipital groove matching that of the interference screw noted above. The superior anchor was placed approximately 1.0 cm superior to the inferior anchor. These absorbable anchors had nonabsorbable number-2 sutures with swaged needles on each end (Panalok; DePuy Mitek, Inc.). The anchor sutures were passed through the tendon and tied, bringing the tendon into the base of the bicipital groove (Figure ). Each arm of the suture was then passed first through the tendon and then through the transverse ligament medially (Figure ) and laterally (Figure ) so that the ligament could be closed over the top of the tendon. We then reinforced that repair of the transverse ligament with 2 absorbable sutures passed through the ligament and the biceps tendon using a technique with each suture placed in a figure-8 configuration. In both techniques, the distal end of the tendon was released from the muscle and a loop was created using a number-5 braided, nonabsorbable Ticron suture with a Krackowtype stitch. ¹⁷ The entire specimen was then mounted in a ring clamp with the humerus in a vertical orientation. The distal loop was placed into a hook attached to the actuator of the materials testing machine (MTS Systems Corp, Eden Prairie, Minnesota) (Figure ). All specimens were preloaded to 5 N and then distracted at 5 mm/sec until failure of the repair occurred. The mode of failure and the load at failure were recorded. The possible modes of failure were: the device pulled out of the bone, the tendon pulled the suture out of the device (anchor), the tendon ripped out of the device (screw), or the tendon failed before the fixation device pulled out.

Figure 1:. After placing the anchors and tying the tendon down, 1 limb of the suture anchor is passed laterally through the transverse humeral ligament and tied.

Figure 2:. The second limb of the suture anchor is then passed medially through the transverse humeral ligament.

Figure 3:. The medial and lateral limbs are then tied, completing the repair of the transverse humeral ligament. The repair is reinforced with a simple absorbable suture. Figures © JHU 2011. Department of Art as Applied to Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.

Figure 4:. Specimens were tested to failure using the materials testing machine.

We analyzed the effect of repair technique on failure load using a standard linear regression with random effects to account for the paired specimens. Statistical analysis of the load to failure was performed using Stata10 (StataCorp LP, College Station, Texas). Statistical significance was set atP<.05.

Results

In all of our specimens, the tendon failed at the suture or interference screw interface with the tendon. There were no failures of the suture anchor eyelets or by pullout of the suture anchor or interference screw from the bone. Mean (95% confidence interval [CI]) failure load for the suture anchor was 263.2 N (range, 221.7–304.6 N) and was significantly greater than that for the interference screw repair 159.4 N (range, 118.4–200.5 N).

Discussion

This study shows that a technique using 2 suture anchors reinforced with 2 absorbable sutures provides a higher load to failure than that of interference screws alone. This finding is contrary to our original hypothesis and is important for the practitioner who performs biceps tenodesis because previous studies have suggested that interference screw fixation is superior to suture anchor fixation alone. ^10,16However, it is important to recognize that we performed both techniques as open, not arthroscopic, procedures. The suture anchor technique described and tested here was designed for use with a mini-open or for other open approaches to the proximal humerus.

Some of the differences between our findings and those previously reported in the literature ^10,16,18 may be the result of differences in surgical technique, such as the location of the anchors, type of anchor, and method of suture fixation to the biceps tendon. Richards and Burkhart ¹⁰ performed a similar biomechanical study using 2 metallic suture anchors and compared the results to that of an interference screw. They placed the suture anchors approximately 5 mm apart in the superior bicipital groove. In their study, the suture anchors were placed into the tendon using a simple mattress stitch.

Ozalay et al ¹⁶ used a single metallic suture anchor placed in the bone of the proximal humerus outside of the bicipital groove. The tendon was secured to the biceps tendon using a Kessler stitch, and 1 arm of the suture was passed through the suture eyelet before impacting the anchor into the bone. ¹⁰

Mazzoca et al ¹⁸ compared 4 types of biceps tenodesis techniques, and no statistical difference was noted in the load to failure for all of the techniques. In their study, they used 2 metallic and barbed suture anchors placed in the bicipital groove with the sutures secured in the tendon using a Mason-Allen technique.

Because our study was a biomechanical investigation, clinical study is needed to verify if suture anchor techniques such as this will provide satisfactory results in vivo. Some authors have suggested that the bicipital groove has too many pain fibers and have recommended tenodesis outside of the bicipital groove. ^13,19 Mazzoca et al ²⁰ studied 41 patients treated with subpectoral biceps tenodesis with interference screw fixation and found good to excellent clinical results in all. Millett et al ¹³ retrospectively studied patients treated with suture anchor fixation or interference screw fixation at the inferior aspect of the bicipital groove. They showed no statistically significant difference in the prevalence of pain at the fixation site between the interference screw (3%) and the suture anchor fixation (7%).

There are several limitations of our study. First, we tested only load to failure and did not conduct cyclical testing to replicate the type of stress the repair might experience clinically. Second, the age and bone density of the cadavers might have influenced the load to failure, but the load to failure in our study was similar to that reported in other studies. ^10,16,20 A review of the literature shows that the load to failure for interference screw fixation ranged from 233.5 N ¹⁰ to 252.4 N ²⁰ (mean, 241.7 N), and that load to failure using suture anchors for biceps tenodesis ranged from 129.0 N ¹⁶ to 164.8 N ²⁰ (mean, 143.1 N).

Conclusion

We found that a biceps tenodesis technique using 2 suture anchors and 2 absorbable sutures with a repair of the transverse ligament has a load to failure greater than that of a technique using an interference screw. Additional biomechanical study, such as cyclical testing, is needed to further compare this technique to others described in the literature. Lastly, a clinical study of this technique using suture anchors is needed to determine if it results in adequate pain relief and successful biceps tenodesis without failures.

For further information: http://www.orthosupersite.com/view.aspx?rid=85235

BUSINESS OF ORTHOPEDICS

Posted on the ORTHOSuperSite August 3, 2011

Study finds top-ranked hospitals typically run by physicians

Findings published in Social Science and Medicine report that the top-performing hospitals are typically led by physicians rather than non-physician managers.

The conclusions run counter to modern trends in the western world that place generally trained managers — rather than those with medical degrees — at the helm of hospitals.

“Over the last few decades, there has been a growing tendency for hospital boards to appoint managers as CEOs,” report author Amanda H. Goodall, PhD, explained in a release. “These findings raise some warning signs over that trend … according to the latest data, outstanding hospitals tend to be those run by somebody with a medical degree. I was surprised by the strength of the pattern.”

Ranking hospitals

Goodall’s study involved collecting data on the top 100 U.S. hospitals in 2009 as identified by the US News and World Report’s “Best Hospitals” ranking across several categories. The ranking originally listed 50 hospitals in each category, so the other 50 in each category were put together through analysis of US News and World Report’s grading system as applied to the remaining hospitals.

Data on each hospital’s CEO were obtained through hospital websites and, in some cases, personal contact with relevant institutions. CEOs were categorized as either physician-leaders or leaders who arenon-physician managers. The study used obtainment of a medical degree as a measuring point for which CEOs qualified as physician-leaders. Goodall reported three nurses were among the CEOs in the cohort — these individuals were categorized as non-physicians.

Cause-and-effect

The results of the study reportedly show that hospital quality scores are approximately 25% higher in physician-run hospitals than in those run by non-physician managers.

Goodall stressed that although the results point toward better hospitals being run by physicians, more research is needed before cause-and-effect can truly be understood.

“This paper does not establish that physicians make more effective leaders when compared with professional managers; but it starts the empirical process,” Goodall wrote. “It finds … that hospitals positioned higher in the US News and World Report’s ‘Best Hospitals’ ranking are led disproportionately by physicians.”

“This is an intriguing pattern but these snapshot results for a single point in time do not prove that doctors make the best heads of hospitals, although they are consistent with that claim,” she added. “More research following a range of hospitals through time is urgently needed.”

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