Arthroscopy: The Journal of Arthroscopic and Related Surgery - Articles in Press

Hamstring Strength Recovery After Hamstring Tendon Harvest for Anterior Cruciate Ligament Reconstruction: A Comparison Between Graft Types - Corrected Proof

Clare L. Ardern, Kate E. Webster, Nicholas F. Taylor, Julian A. Feller — 2010-02-01

Purpose: The purpose of this study was to investigate hamstring strength after harvest of 1 or 2 hamstring tendons for anterior cruciate ligament reconstruction.Methods: We recruited 50 individuals who had returned to regular sporting activity to participate in a comparative study at a mean of 32.5 months after anterior cruciate ligament reconstructive surgery (30 in semitendinosus-gracilis group and 20 in semitendinosus group). Isokinetic hamstring strength (at 60°/s and 180°/s with the peak torque and torque produced at 60°, 90°, and 105° of knee flexion recorded) and isometric hamstring strength (at 30°, 90°, and 105° of knee flexion) were measured, and the standing knee flexion angle was used to evaluate functional hamstring strength recovery.Results: No significant differences between the groups were found in any of the isometric or isokinetic strength measures or in the standing knee flexion angle. No relation was found between the standing knee flexion angle and the isometric hamstring strength results obtained at 105° of knee flexion (r2 = 0.034).Conclusions: These findings show that the choice of hamstring tendon graft—that is, semitendinosus alone or semitendinosus and gracilis—is unlikely to significantly influence postoperative hamstring strength outcomes in athletes returning to sports postoperatively. Both graft choices showed strength deficits of between 3% and 27% compared with the nonoperated limb, indicating that hamstring strength deficits persist despite successful completion of rehabilitation. The results also show that the standing knee flexion angle should not be used as a surrogate clinical measure of hamstring strength.Level of Evidence: Level III, retrospective comparative study.

Arthroscopic Ganglionectomy Through an Intrafocal Cystic Portal for Wrist Ganglia - Corrected Proof

2010-02-01

Purpose: A retrospective study was conducted on arthroscopic ganglionectomy in wrists using a novel intrafocal cystic portal. The safety and efficacy of this technique were assessed by treatment of 15 wrists in 15 patients.Methods: Arthroscopic ganglionectomy was performed by the same surgeon with the patient under general anesthesia or regional block. Preoperative complaints, intraoperative findings, and postoperative results of all the patients were reported. The mean follow-up was 15.3 months. Functional assessment by use of modified Mayo wrist scores, patient satisfaction, and recurrence were included in the follow-up evaluation.Results: Two thirds of the patients acquired good to excellent results, whereas the results for the remaining third were fair. Complications included 1 recurrence and 1 case of transient paresthesia sensation. The most common arthroscopic findings were capsular and ligament lesions, rather than ganglionic stalks.Conclusions: Arthroscopic ganglionectomy through an intrafocal cystic portal is a safe and efficacious option for the treatment of painful wrist ganglia.Level of Evidence: Level IV, therapeutic case series.

False FHL: A Normal Variant Posing Risks in Posterior Hindfoot Endoscopy - Corrected Proof

Phinit Phisitkul, Annunziato Amendola — 2010-01-25

Abstract: Posterior hindfoot endoscopy has been more commonly used in the treatment of various pathologies by surgeons with different arthroscopic experience. The flexor hallucis longus is usually the initial and most important landmark serving as a medial boundary for the arthroscope and instruments to avoid inadvertent injury to the tibial nerve and vessels. We report 2 cases in which the presence of the peroneocalcaneus internus muscle, “false FHL,” imitated the flexor hallucis longus, risking imminent neurovascular injury during the initial endoscopic exposure. Awareness of this rare anatomic variation, preoperative magnetic resonance imaging studies, and intraoperative differentiation techniques were found helpful to avoid devastating complications.

Femoral Nerve Block Use in Anterior Cruciate Ligament Reconstruction Surgery: A Systematic Review - Corrected Proof

Nathan A. Mall, Rick W. Wright — 2010-01-25

Purpose: The goal of this study was to determine whether femoral nerve blocks (FNBs) provide patients undergoing anterior cruciate ligament reconstruction greater pain relief or other benefits compared with more standard pain medication regimens.Methods: We searched PubMed, EMBASE, and the Cochrane Database using the following search terms: “ACL or anterior cruciate ligament” and “femoral nerve block or peripheral nerve block” or “regional anesthesia.” Thirteen studies were found that fit the inclusion criteria of being randomized controlled trials with a Level of Evidence of I or II, comparing FNB or 3-in-1 blocks with control groups undergoing various multimodal pain regimens.Results: Only 5 of the 13 studies found a significant difference in pain relief with FNB compared with the control groups; however, the difference in several of the studies may not be clinically relevant. Of the 13 studies, 6 examined parameters other than pain, and only 1 study found a greater incidence of nausea and sedation in its control group. Patient satisfaction was examined in 2 studies, with both finding no difference between groups. Nine studies used a single graft type, and the two studies using multiple graft types accounted for this in their analyses.Conclusions: On the basis of the available Level I and II data from randomized controlled trials, there appears to be no evidence that FNBs add additional benefit over multimodal analgesia. FNBs have not been shown to significantly affect patient pain, readiness for discharge, or outcome scores. There is a small but identifiable risk associated with performing FNBs, with potentially catastrophic effects.Level of Evidence: Level II, systematic review of Level I and II randomized controlled trials with minimal heterogeneity.

The Incidence of Early Metallic Suture Anchor Pullout After Arthroscopic Rotator Cuff Repair - Corrected Proof

Eric C. Benson, Joy C. MacDermid, Darren S. Drosdowech, George S. Athwal — 2010-01-25

Purpose: The purpose of this study was to identify the incidence of metallic suture anchor pullout after arthroscopic rotator cuff repair and determine the impact of tear size on the risk of pullout.Methods: A retrospective review of 269 patients (550 metallic suture anchors) who underwent arthroscopic rotator cuff repair between January 2006 and January 2009 was conducted. Inclusion criteria included patients aged 18 years or older, a minimum of 6 weeks' radiographic follow-up, and the use of 1 or more metallic suture anchors for partial or complete rotator cuff repair. The mean age of the cohort at the time of surgery was 55 years (range, 29 to 86 years), and there were 189 men and 80 women.Results: Early anchor pullout occurred in 6 patients (9 anchors). The overall incidence of early metallic suture anchor pullout in this cohort was 2.4% (95% confidence interval, 0.5% to 4.3%). The incidence in rotator cuff tears less than or equal to 3 cm was 0.5%, and the incidence in tears greater than 3 cm was 11%. Patients undergoing arthroscopic rotator cuff repair of a tear greater than 3 cm in size were at a significantly higher risk of having early metallic suture anchor pullout than patients undergoing repair of a smaller tear (relative risk, 22; P = .001). Among the 61 patients undergoing arthroscopic subscapularis repair, no suture anchor failures were observed at the lesser tuberosity. Of the 9 anchors that failed, 8 (89%) pulled out of the posterior aspect of the greater tuberosity.Conclusions: There is a minimal risk of suture anchor pullout in small- to medium-sized tears; however, this risk increases with larger tear sizes. We recommend routine radiographic follow-up after use of metallic anchors to ensure identification of early failure by anchor pullout.Level of Evidence: Level III, prognostic case series.

Evaluation of a New Femoral Fixation Device in a Simulated Anterior Cruciate Ligament Reconstruction - Corrected Proof

Andrew Speirs, David Simon, Peter Lapner — 2010-01-25

Purpose: The purpose of this in vitro biomechanical study was to determine the cyclic elongation and failure properties of a new anterior cruciate ligament (ACL) reconstruction device and compare the results with several devices that are currently available.Methods: We performed 10 ACL reconstructions in 4 groups using fresh porcine femurs and doubled lateral extensor of the toes tendons. Manufacturer guidelines were followed for fixation by use of either of 2 cortical suspension devices (XO Button [ConMed Linvatec, Largo, FL] and EndoButton CL [Smith & Nephew, Andover, MA]), a bio-interference screw (BioScrew; ConMed Linvatec), or a corticocancellous fixation device (Pinn-ACL; ConMed Linvatec). Reconstructions were subjected to cyclic loading to 150 N for 2,000 cycles, followed by static failure tests.Results: The two cortical suspension devices performed similarly to one another: the XO Button device had a significantly lower elongation amplitude than the EndoButton (P < .05). There were no significant differences in longer-term creep performance or static strength or stiffness. Compared with an interference screw, the XO Button had significantly less creep and higher failure load (P < .05). The corticocancellous device had the lowest creep and cyclic elongation amplitude and the highest strength and stiffness of the devices tested.Conclusions: In this in vitro evaluation, reconstructions with the XO Button and EndoButton exhibited very similar biomechanical performance, and our hypothesis was not supported: the XO Button did not limit creep more than the EndoButton.Clinical Relevance: The results of this preclinical in vitro testing suggest that the new device is expected to provide clinical results similar to those of the EndoButton, a well-established device for ACL reconstruction.

The Outcome of Type II SLAP Repair: A Systematic Review - Corrected Proof

Kalyan Gorantla, Corey Gill, Rick W. Wright — 2010-01-25

Purpose: The purpose of this study was to systematically review the literature regarding the outcome of arthroscopic repair of type II SLAP lesions in order to assess the effectiveness of current methods of treatment.Methods: We performed a systematic review of the results of repair of type II SLAP lesions. Inclusion criteria included outcome studies of repair of type II SLAP lesions with minimum 2-year follow-up and Level IV evidence or higher published in the English language in peer-reviewed journals.Results: There is no Level I or II evidence for SLAP repair outcome. Regarding the general outcome after type II SLAP repair, the percentage of good and excellent results ranged from 40% to 94%. Return to previous level of play ranged from 20% to 94%. Overhead athletes are the most challenging to return to the previous level of performance for this diagnosis, and their return rate reflects this. Five studies reported these results, and the rate of return ranged from 22% to 64% for baseball players.Conclusions: Arthroscopic repair of type II SLAP tears results in overall excellent results for individuals not involved in throwing or overhead sports. The results of type II SLAP repair in throwing or overhead athletes are much less predictable. Future studies should be prospective in nature and at least use a longitudinal prospective cohort design to determine predictors of outcome.Level of Evidence: Level IV, systematic review of Level III and IV studies.

Effect of Suture Size and Type on Bone Cutout in Transosseous Tendon Repairs - Corrected Proof

2010-01-25

Purpose: We compared bone cutout of polyester and polyblend suture in 2 suture sizes with static and cyclic loading in a Sawbone model (Pacific Research Laboratories, Vashon, WA).Methods: Polyester and polyblend sutures in both No. 2 and No. 5 sizes were placed through transosseous tunnels in closed-cell polyurethane foam and tied over the bar of an electromechanical load frame at a fixed height. Seven sutures in each group were pulled at a rate of 1 mm/s until bone cutout occurred. Another set of 28 sutures were cyclically loaded at increasing loads until failure.Results: With static and cyclic loads, No. 5 polyester suture (Ethibond; Ethicon, Somerville, NJ) and No. 5 polyblend suture (FiberWire; Arthrex, Naples, FL) had a higher cutout load than the No. 2 sutures (P < .001). No. 2 polyblend suture had a higher static failure load than No. 2 polyester suture (P = .02). With cyclic loading, No. 2 polyblend suture had a higher load to cutout than No. 2 polyester suture (P = .01), and No. 5 polyblend suture had a higher load to cutout than No. 5 polyester suture (P = .003).Conclusions: No. 2 sutures showed bone cutout at lower forces under static and cyclic loading as compared with No. 5 sutures in this Sawbone model, and no decrease in performance with regard to bone cutout was noted with polyblend as compared with polyester.Clinical Relevance: No. 5 polyester or polyblend suture may be preferable to No. 2 suture to avoid bone cutout in tendon-to-bone repair, and No. 5 polyblend may be preferable to No. 5 polyester to avoid bone cutout.

Anterior Cruciate Ligament Reconstruction Using Patellar Tendon Allograft: An Age-Dependent Outcome Evaluation - Corrected Proof

F. Alan Barber, Jorge Aziz-Jacobo, Fernando Barrera Oro — 2010-01-25

Purpose: To compare the outcomes of a consecutive series of nonrevision bone–patellar tendon–bone (BPTB) allograft anterior cruciate ligament (ACL) reconstructions in patients aged 40 years or older and patients aged younger than 40 years.Methods: Prospectively collected data from consecutive BPTB allograft ACL reconstructions fixed with biodegradable interference screws and performed by a single surgeon were analyzed by use of established outcome measures. Preoperative and postoperative outcome assessments included Cincinnati, Lysholm, and Tegner scores and International Knee Documentation Committee (IKDC) activity scores. Lachman test, pivot-shift test, and KT arthrometer (MEDmetric, San Diego, CA) measurements were obtained at a minimum of 24 months after surgery.Results: In total, 32 patients met the inclusion criteria (21 men and 11 women). The mean follow-up was 35 months (range, 24 to 58 months). Of the patients, 21 were aged younger than 40 years (66%) and 11 were aged 40 years or older (34%). The mean age was 35 years (range, 18 to 55 years). In patients aged younger than 40 years, the mean postoperative Cincinnati score was 82.4 (39.1 preoperatively); Tegner score, 6.2 (3.9 preoperatively); Lysholm score, 89.5 (46.8 preoperatively); and IKDC activity score, 2.7 out of 4 (1.7 preoperatively). Five patients had a positive postoperative Lachman test, but none had a positive pivot-shift test. KT examinations showed a manual maximum difference of less than 3 mm in all but 1 patient (mean, 0.7 mm). In patients aged 40 years or older, the mean postoperative Cincinnati score was 83.8 (44.4 preoperatively); Tegner score, 6.6 (3.9 preoperatively); Lysholm score, 88.8 (50.1 preoperatively); and IKDC activity score, 2.7 out of 4 (2.1 preoperatively). One patient had a positive postoperative Lachman test, but none had a positive pivot-shift test. KT examinations showed a manual maximum difference of less than 3 mm in all but 1 patient (mean, 1.3 mm).Conclusions: The outcomes of BPTB allograft ACL reconstructions were not different both subjectively and objectively for patients aged 40 years or older and patients aged younger than 40 years. BPTB allograft ACL reconstruction provides consistent results for patients of all age groups.Level of Evidence: Level III, retrospective comparative study.

Does the Literature Confirm Superior Clinical Results in Radiographically Healed Rotator Cuffs After Rotator Cuff Repair? - Corrected Proof

2010-01-18

Purpose: Because recurrent or persistent defects in the rotator cuff after repair are common, we sought to clarify the correlation between structural integrity of the rotator cuff and clinical outcomes through a systematic review of relevant studies.Methods: Medline, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and the Cochrane Central Register of Controlled Trials were searched for all literature published from January 1966 to December 2008 that used the key words shoulder, rotator cuff, rotator cuff tear, rotator cuff repair, arthroscopic, integrity, healed, magnetic resonance imaging (MRI), computed tomography arthrography (CTA), and ultrasound. The inclusion criteria were studies (Levels I to IV) that reported outcomes after arthroscopic rotator cuff repair in healed and nonhealed repairs based on ultrasound, CTA, and/or MRI. Exclusionary criteria were studies that included open repair or subscapularis repair and studies that did not define outcomes based on healed versus nonhealed but rather used another variable (i.e., repair technique). Data were abstracted from the studies including patient demographics, tear characteristics, surgical procedure, rehabilitation, strength, range of motion, clinical scoring systems, and imaging studies.Results: Thirteen studies were included in the final analysis: 5 used ultrasound, 4 used MRI, 2 used CTA, and 2 used combined CTA/MRI for diagnosis of a recurrent tear. Statistical improvement in patients who had an intact cuff at follow-up was seen in Constant scores in 6 of 9 studies; in University of California, Los Angeles scores in 1 of 2 studies; in American Shoulder and Elbow Surgeons scores in 0 of 3 studies; and in Simple Shoulder Test scores in 0 of 2 studies. Increased range of motion in forward elevation was seen in 2 of 5 studies and increased strength in forward elevation in 5 of 8 studies.Conclusions: The results suggest that some important differences in clinical outcomes likely exist between patients with healed and nonhealed rotator cuff repairs. Further study is needed to conclusively define this difference and identify other important prognostic factors related to clinical outcomes.Level of Evidence: Level IV, systematic review.

Ligamentization of Tendon Grafts Treated With an Endogenous Preparation Rich in Growth Factors: Gross Morphology and Histology - Corrected Proof

2010-01-18

Purpose: To investigate whether the application of a particular platelet-rich plasma preparation rich in growth factors (PRGF) during anterior cruciate ligament (ACL) surgery gives a potential advantage for better tendon graft ligamentization.Methods: This study included 37 volunteers who underwent either conventional (control group, n = 15) or PRGF-assisted (n = 22) ACL reconstruction with an autogenous hamstring and required second-look arthroscopy to remove hardware or loose bodies, treat meniscal tears or plica syndrome, or resect cyclops lesions at 6 to 24 months after ACL surgery. The gross morphologies of the grafts were evaluated on second-look arthroscopy by use of the full arthroscopic score (0 to 4 points) to evaluate graft thickness and apparent tension (0 to 2 points) plus synovial coverage (0 to 2 points). At the same time, biopsy specimens were harvested uniformly from the grafted tendons. In these specimens the histologic transformation of the tendon graft to ACL-like tissue was evaluated by use of the Ligament Tissue Maturity Index, and a score to assess the progression of new connective tissue enveloping the graft was created by use of 3 criteria previously used to characterize changes during ligament healing: cellularity, vascularity, and collagen properties.Results: The overall arthroscopic evaluation of PRGF-treated grafts showed an excellent rating in 57.1% of the knees (score of 4) and a fair rating in 42.9% (score of 2 or 3). In contrast, evaluation of untreated grafts showed an excellent rating in 33.3% of the knees, a fair rating in 46.7%, and a poor rating in 20% (score of 0 or 1). Overall, arthroscopic evaluations were not statistically different between PRGF and control groups (P = .051). PRGF treatment influenced the histologic characteristics of the tendon graft, resulting in tissue that was more mature than in controls (P = .024). Histologically evident newly formed connective tissue enveloping the graft was present in 77.3% of PRGF-treated grafts and 40% of controls. The appearance of the connective tissue envelope changed with increasing time from surgery. On the basis of the histologic findings, we suggest that the remodeling of PRGF-treated grafts involves the formation of synovial-like tissue enveloping the graft. This tissue is eventually integrated in the remodeled tendon graft, conferring a similar appearance to the normal ACL.Conclusions: The use of PRGF influenced the histologic characteristics of tendon grafts, resulting in more remodeling compared with untreated grafts. We have shown temporal histologic changes during the 6- to 24-month postoperative period of graft maturation, with newly formed connective tissue enveloping most grafts treated with PRGF.Level of Evidence: Level III, case-control study.

Medial-Row Failure After Arthroscopic Double-Row Rotator Cuff Repair - Corrected Proof

2010-01-04

Abstract: We report 4 cases of medial-row failure after double-row arthroscopic rotator cuff repair (ARCR) without arthroscopic subacromial decompression (ASAD), in which there was pullout of mattress sutures of the medial row and knots were caught between the cuff and the greater tuberosity. Between October 2006 and January 2008, 49 patients underwent double-row ARCR. During this period, ASAD was not performed with ARCR. Revision arthroscopy was performed in 8 patients because of ongoing symptoms after the index operation. In 4 of 8 patients the medial rotator cuff failed; the tendon appeared to be avulsed at the medial row, and there were exposed knots on the bony surface of the rotator cuff footprint. It appeared that the knots were caught between the cuff and the greater tuberosity. Three retear cuffs were revised with the arthroscopic transtendon technique, and one was revised with a single-row technique after completing the tear. ASAD was performed in all patients. Three of the four patients showed improvement of symptoms and returned to their preinjury occupation. Impingement of pullout knots may be a source of pain after double-row rotator cuff repair.

The Effect of a Nonanatomic Repair of the Meniscal Horn Attachment on Meniscal Tension: A Biomechanical Study - Corrected Proof

Christian Stärke, Sebastian Kopf, Karl-Heinz Gröbel, Roland Becker — 2010-01-04

Purpose: The purpose of this biomechanical study was to investigate the potential effect of a nonanatomic repair of the meniscal horn attachment on the resultant circumferential tension in a large animal model and to show that the circumferential tension of the meniscus affects the local stress of the cartilage.Methods: All investigations were done in the medial compartment of porcine knees. First, the anterior horn attachment of the meniscus was mechanically separated from the surrounding tibial bone and fitted with a force transducer (n = 8). The femorotibial joint was loaded in compression at different flexion angles, and the resultant tension at the horn attachment was recorded. The measurements were done with the horn attachment at its anatomic position and repeated with the horn attachment being displaced medially or laterally by 3 mm. In the second part the local deformation of the cartilage under a femorotibial compressive load was measured at different levels of meniscal hoop tension (n = 5).Results: A nonanatomic position of the horn attachment had a significant effect on the resultant tension (P < .01). Placing the horn attachment 3 mm medially decreased the tension at the horn attachment by 49% to 73%, depending on flexion angle and femorotibial load. The opposite placement resulted in a relative increase in the tension by 28% to 68%. Lower levels of meniscal hoop tension caused increased deformation of the cartilage (P < .05), indicating increased local stress.Conclusions: A nonanatomic position of the horn attachment strongly affects conversion of femorotibial loads into circumferential tension. There is a narrow window for a functionally sufficient repair of meniscal root tears. Clinical Relevance: Although clinical inferences are limited because the specimens used were from a different species, there seems to be only a narrow window for a mechanically sufficient repair of root tears.

Electrospun Synthetic Polymer Scaffold for Cartilage Repair Without Cultured Cells in an Animal Model - Corrected Proof

2009-12-31

Purpose: The purpose of our study was to explore the possibility that an electrospun bioabsorbable scaffold could be used in the treatment of a full-thickness articular defect without the addition of exogenous cells in a rabbit model.Methods: Two types of poly(D,L-lactide-co-glycolide) (PLG) scaffolds, a solid cylindrical type and a cannulated tubular type, were made with the electrospinning method. Osteochondral defects, 5 mm in diameter and 5 mm in depth, made on the femoral condyles of rabbits were filled with these scaffolds, and the repair process was investigated histologically.Results: In the groups in which the defect was filled with the scaffold, fibrous tissue at the articular surface of the scaffold was observed at postoperative week 2. Thereafter cartilage at the articular surface and bone at the subchondral zone were regenerated, and the repaired cartilage was maintained through postoperative week 24. By contrast, the untreated defect was filled with hematoma at postoperative week 2; thereafter regenerated cartilage and bone were observed. However, the surface of the articular cartilage was not regular, and regenerated cartilage was not well organized. The histologic scores of the groups in which the defect was filled with cannulated tubular electrospun PLG scaffolds were significantly higher than those of the untreated defect group at postoperative weeks 12 and 24 (P < .01).Conclusions: The electrospun PLG scaffold could repair a 5-mm osteochondral defect created in the rabbit model without exogenous cultured cells. Clinical Relevance: The electrospun PLG scaffold could repair full-thickness osteochondral defects. The cannulated type of PLG scaffold has the possibility to lead not only to good regeneration of cartilage but also to easy transplantation by use of a guidewire through the cannulas in the scaffold.

A Biomechanical Comparison of 3 Reconstruction Techniques for Posterolateral Instability of the Knee in a Cadaveric Model - Corrected Proof

2009-12-31

Purpose: The objective of this study was to compare the varus and external rotatory laxity of reconstructed knees by use of 3 different reconstruction techniques that address posterolateral instability of the knee: popliteus tendon (PT) and lateral collateral ligament (LCL) reconstruction, PT and popliteofibular ligament (PFL) reconstruction, and PFL and LCL reconstruction.Methods: We divided 36 fresh-frozen cadaveric knees into 3 groups of 12, and each group was assigned to a reconstruction technique: PT-LCL reconstruction with the posterior tibialis tendon, PT-PFL reconstruction with the patellar tendon and bone (Warren technique), and PFL-LCL reconstruction with the semitendinosus tendon (Larson technique). Each specimen was fixed with an Ilizarov external fixator and mounted on a custom-designed apparatus that was made to measure posterolateral instability of the knee, that is, external rotatory and varus laxity in the intact state, after cutting, and in the postoperative state at every 30° from 0° to 90°.Results: There were no significant differences between the 3 techniques with external rotation and varus laxity in all specimens.Conclusions: PT-LCL reconstruction was comparable to the other 2 established techniques: PT-PFL reconstruction (Warren technique) and PFL-LCL reconstruction (Larson technique). However, the original strength of the native knee could not be achieved with any of the techniques. Clinical Relevance: All techniques restored the posterolateral stability of the knee to near normal, with none of them being superior.

The Geometric Classification of Rotator Cuff Tears: A System Linking Tear Pattern to Treatment and Prognosis - Corrected Proof

James Davidson, Stephen S. Burkhart — 2009-12-28

Abstract: A valuable classification system allows for communication among surgeons and/or other investigators and offers information on treatment and prognosis. It provides a means for comparison of epidemiologic data and treatment outcomes. There is no current standard classification for rotator cuff tears. Authors and practicing orthopaedists use a variety of descriptions when communicating about cuff tears. Older classifications do not use 3-dimensional information derived from the present use of arthroscopy and magnetic resonance imaging. The new geometric classification offers guidance on treatment and prognosis. Type 1, crescent-shaped tears are repaired end to bone and have a good to excellent prognosis. Type 2, longitudinal (L- or U-shaped) tears are repaired side to side with margin convergence and have a good to excellent prognosis. Type 3, massive contracted tears have coronal and sagittal dimensions greater than 2 × 2 cm on preoperative magnetic resonance imaging; are repaired with interval slides or partial repair; and have a fair to good prognosis. Type 4, rotator cuff arthropathy tears have end-stage degenerative changes of the glenohumeral joint and have articulation of the humeral head with the undersurface of the acromion; are irreparable; and require arthroplasty if surgery is considered. This classification describes complete tears of the superior and posterior rotator cuff, supraspinatus, infraspinatus, and teres minor. Additional notation can be made regarding the presence of related pathology including tears of the subscapularis, biceps, or labrum; instability or arthritic change of the glenohumeral or acromioclavicular joints; or fatty degeneration of the cuff.

Biomechanical Advantages of Triple-Loaded Suture Anchors Compared With Double-Row Rotator Cuff Repairs - Corrected Proof

2009-12-28

Purpose: To evaluate the strength and suture-tendon interface security of various suture anchors triply and doubly loaded with ultrahigh–molecular weight polyethylene–containing sutures and to evaluate the relative effectiveness of placing these anchors in a single-row or double-row arrangement by cyclic loading and then destructive testing.Methods: The infraspinatus muscle was reattached to the original humeral footprint by use of 1 of 5 different repair patterns in 40 bovine shoulders. Two single-row repairs and three double-row repairs were tested. High-strength sutures were used for all repairs. Five groups were studied: group 1, 2 triple-loaded screw suture anchors in a single row with simple stitches; group 2, 2 triple-loaded screw anchors in a single row with simple stitches over a fourth suture passed perpendicularly (“rip-stop” stitch); group 3, 2 medial and 2 lateral screw anchors with a single vertical mattress stitch passed from the medial anchors and 2 simple stitches passed from the lateral anchors; group 4, 2 medial double-loaded screw anchors tied in 2 mattress stitches and 2 push-in lateral anchors capturing the medial sutures in a “crisscross” spanning stitch; and group 5, 2 medial double-loaded screw anchors tied in 2 mattress stitches and 2 push-in lateral anchors creating a “suture-bridge” stitch. The specimens were cycled between 10 and 180 N at 1.0 Hz for 3,500 cycles or until failure. Endpoints were cyclic loading displacement (5 and 10 mm), total displacement, and ultimate failure load.Results: A single row of triply loaded anchors was more resistant to stretching to a 5- and 10-mm gap than the double-row repairs with or without the addition of a rip-stop suture (P < .05). The addition of a rip-stop stitch made the repair more resistant to gap formation than a double row repair (P < .05). The crisscross double row created by 2 medial double-loaded suture anchors and 2 lateral push-in anchors stretched more than any other group (P < .05).Conclusions: Double-row repairs with either crossing sutures or 4 separate anchor points were more likely to fail (5- or 10-mm gap) than a single-row repair loaded with 3 simple sutures.Clinical Relevance: The triple-loaded anchors with ultrahigh–molecular weight polyethylene–containing sutures placed in a single row were more resistant to stretching than the double-row groups.

Factors Affecting Recovery After Arthroscopic Labral Debridement of the Hip - Corrected Proof

Ho H. Lee, Alison K. Klika, Boris Bershadsky, Viktor E. Krebs, Wael K. Barsoum — 2009-12-28

Purpose: The purpose of this study was to develop and validate a model predicting whether patients would have shorter-than-typical or longer-than-typical recoveries after hip arthroscopy for labral tears.Methods: We retrospectively reviewed 268 cases of hip arthroscopy implemented between 2000 and 2007 by 2 orthopaedic surgeons at our institution. The development cohort consisted of patients with magnetic resonance angiography–identified labral tears and a history and physical examination consistent with either labral pathology or loose bodies. Univariate analysis targeted preoperative patient characteristics correlated with the risk of longer-than-typical recoveries. Multivariate logistic regression was applied to generate an algorithm predicting risk of longer-than-typical recovery based on baseline characteristics. The algorithm was tested in the validation sample of 52 patients who were treated in 2007 and was found to be valid.Results: Five predictors for longer-than-typical recovery were identified: Workers' Compensation status, female gender, use of pain medications, presence of a limp, and presence of a lateral labral tear. The multivariate algorithm was developed and successfully validated.Conclusions: This study identifies many new predictors of recovery, and it also corroborates those that have already been identified. The 5 predictors for longer-than-typical recovery identified by our validated multivariate algorithm were Workers' Compensation status, female gender, use of pain medications, presence of a limp, and presence of a lateral labral tear.Level of Evidence: Level IV, therapeutic case series.

The Actual Tendon-Bone Interface Strength in a Rabbit Model - Corrected Proof

2009-12-28

Purpose: The purpose of this study was to evaluate the strength of the interface throughout the entire integration process by use of tendon graft reinforced with a suture material compared with nonreinforced tendon graft.Methods: Using 60 skeletally mature female Japanese white rabbits, we performed biomechanical testing and histologic evaluation to compare tendon grafts reinforced with a suture material (suture group) and nonreinforced grafts (control group). The tendon graft was drawn through a bone tunnel measuring 2.5 mm in diameter and was tightly fixed. For biomechanical testing, the tendon graft was tested in tensile loading along the axis of the bone tunnel at a crosshead speed of 100 mm/min.Results: On biomechanical testing, at 4, 6, 8, and 12 weeks, tendon grafts had pulled out of the bone tunnel in the suture group. In the control group all tendon grafts had pulled out at 4 and 6 weeks, and rupture at the midsubstance was seen at 8 and 12 weeks. The failure load–to–tunnel length ratio was significantly larger in the suture group compared with the control group at 8 and 12 weeks. On histologic evaluation, both groups had similar findings with direct attachments to bone by 12 weeks.Conclusions: In this study of the healing characteristics of augmented and nonaugmented tendon grafts placed in a bone tunnel, we found that the suture-augmented tendons had superior failure load–to–tunnel length ratios at 8, 12, and 16 weeks compared with nonaugmented tendons. The failure mode in the augmented grafts was tendon pullout at all time points except 16 weeks, whereas the nonaugmented grafts failed by midsubstance rupture after 8 weeks. Histologically, both groups had similar findings with direct attachments to bone by 12 weeks.Clinical Relevance: The tendon graft has the potential to be pulled out of the bone tunnel after complete integration.

Avoiding Mismatch in Allograft Anterior Cruciate Ligament Reconstruction: Correlation Between Patient Height and Patellar Tendon Length - Corrected Proof

2009-12-28

Purpose: The purpose of this study was to evaluate whether a correlation exists between patient height and soft-tissue patellar tendon length.Methods: Magnetic resonance imaging (1.5 T) was performed for knee pathology on 403 patients. The patellar tendon length was measured in the midsagittal plane by a board-certified musculoskeletal radiologist. Patient height was recorded to the nearest inch. Patients were grouped into 6 subgroups with 4-inch range intervals based on height. The entire study group was analyzed. Subgroup analysis and gender analysis were performed to determine statistical significance.Results: The mean patellar tendon length was 45 ± 7 mm (range, 30 to 66 mm). Wide ranges were noted among each height subgroup irrespective of gender. Significant differences were noted between most height subgroups independent of gender.Conclusions: This study showed that a correlation exists between patient height, gender, and patellar tendon length. Although variation occurs among patients of the same height, significant differences in mean patellar tendon lengths do exist between patients in different height subgroups.Clinical Relevance: Parameters are provided using patient gender and height to reduce the potential for graft-construct mismatch when ordering bone–patellar tendon–bone allografts for anterior cruciate ligament reconstruction.