***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND Controversy exists regarding the optimal technique for arthroscopic rotator cuff repair . The purpose of this multicenter , r and omized , double-blind controlled study was to compare the functional outcomes and healing rates after use of single-row and double-row suture techniques for repair of the rotator cuff . METHODS Ninety patients undergoing arthroscopic rotator cuff repair  were r and omized to receive either a single-row or a double-row repair . The primary objective was to compare the Western Ontario rotator cuff index ( WORC ) score at twenty-four months . Secondary objectives included comparison of the constant and american shoulder and elbow surgeons ( ASES ) scores and strength between groups . Anatomical outcomes were assessed with magnetic resonance imaging ( MRI ) or ultrasonography to determine the postoperative healing rates . RESULTS Baseline demographic data including age ( p = 0.29 ) , sex ( p = 0.68 ) , affected side ( p = 0.39 ) , and rotator cuff tear size ( p = 0.28 ) did not differ between groups . The WORC score did not differ significantly between groups at any time point ( p = 0.48 at baseline , p = 0.089 at three months , p = 0.52 at six months , p = 0.83 at twelve months , and p = 0.60 at twenty-four months ) . The WORC score at each postoperative time point was significantly better than the baseline value . The Constant score , ASES score , and strength did not differ significantly between groups at any time point . Logistic regression analysis demonstrated that a smaller initial tear size and double-row fixation were associated with higher healing rates . CONCLUSIONS No significant differences in functional or quality -of-life outcomes were identified between single-row and double-row fixation techniques . A smaller initial tear size and a double-row fixation technique were associated with higher healing rates as assessed with ultrasonography or MRI . LEVEL OF EVIDENCE Therapeutic level I. See Instructions for Authors for a complete description of levels of evidence Background Recurrent defects after open and arthroscopic rotator cuff repair are common . Double-row repair techniques may improve initial fixation and quality of rotator cuff repair .  Purpose To evaluate the load to failure , cyclic displacement , and anatomical footprint of 4 arthroscopic rotator cuff repair techniques .  Hypothesis Double-row suture anchor repair would have superior structural properties and would create a larger footprint compared to single-row repair . Study Design Controlled laboratory study . Methods Twenty fresh-frozen cadaveric shoulders were r and omly assigned to 4 arthroscopic repair techniques . The repair was performed as either a single-row technique or 1 of 3 double-row techniques : diamond , mattress double anchor , or modified mattress double anchor . Angle of loading , anchor type , bone mineral density , anchor distribution , angle of anchor insertion , arthroscopic technique , and suture type and size were all controlled . Footprint length and width were quantified before and after repair . Displacement with cyclic loading and load to failure were determined . Results There were no differences in load to failure and displacement with cyclic loading between the single-row repair and each double-row repair . All repair groups demonstrated load to failure greater than 250 N. A significantly greater supraspinatus footprint width was seen with double-row techniques compared to single-row repair . Conclusions The single-row repair technique was similar to the double-row techniques in load to failure , cyclic displacement , and gap formation . The double-row anchor repairs consistently restored a larger footprint than did the single-row method . Clinical Relevance The arthroscopic techniques studied have strong structural properties that approached the reported performance of open repair techniques . Double-row techniques provide a larger footprint width ; although not addressed by this study , such a factor may improve the biological quality of repair Purpose The purpose of this study was to compare arthroscopic rotator cuff repair with single-row and double-row techniques because research has demonstrated the superiority of double-row repair from a biological and mechanical point of view but there is no evidence of clinical superiority . Methods A total of 160 patients with a full-thickness rotator cuff tear underwent arthroscopic repair with suture anchors .  They were r and omised into two groups of 80 patients according to the repair technique : single-row ( group 1 ) and double-row ( group 2 ) . Results were evaluated by use of the University of California , Los Angeles ( UCLA ) , American Shoulder and Elbow Surgeons ( ASES ) and Constant question naires , the Shoulder Strength Index ( SSI ) and range of motion . Follow-up time was two years . Magnetic resonance imaging ( MRI ) studies were performed on each shoulder preoperatively and two years after repair . Results One hundred per cent of the patients were followed up . All measurements showed significant improvement compared with the preoperative status . The UCLA score showed significant improvement in group 2 . In over 30-mm tears UCLA and ASES showed significant differences . SSI showed significant improvement in group 2 . Range of motion showed significant improvements in flexion and abduction in group 2 . In under 30-mm tears group 2 showed also significant improvement in internal and external rotation . In MRI studies there were no significant differences . Conclusions At two years follow-up the double-row repair technique showed a significant difference in clinical outcome compared with single-row repair and this was even more significative in over 30-mm tears . No MRI differences were observed More than 75,000  rotator cuff repairs  are performed annually , yet cost-effectiveness data are unavailable . This study examines the cost utility of rotator cuff repair by relating surgical costs to increase in quality -adjusted life-years ( QALYs ) .  Eighty-seven patients were followed up prospect ively for 1 year , during which  cost and quality of life data were collected .  Patient-based utility measures of quality of life ( European Quality -of-Life measure [ EuroQoL ] and Health Utility Index [ HUI ] )  were administered . Changes in these measures generated net QALYs . Finally , life expectancies were applied to generate a cost-effectiveness ratio , and subsequent 1-way sensitivity analyses varied costs , QALYs , and discount rates to determine which factors drive cost-effectiveness . Total costs averaged $ 10,605.20 . Significant improvements were noted in health-related quality of life postoperatively . The estimated mean lifetime gain in QALYs from surgery was 0.81 by use of the HUI and 3.43 by use of the EuroQoL. This yielded cost-effectiveness ratios of $ 13,092.84/QALY by use of the HUI and $ 3,091.90/QALY by use of the EuroQoL. The cost-effectiveness of rotator cuff repair compares favorably with other common interventions in health care and reaches commonly accepted benchmarks for cost-effectiveness PURPOSE Our goal in this analysis was to compare clinical outcomes and radiographic healing rates of double-row ( DR ) transosseous-equivalent versus single-row ( SR ) Mason-Allen configuration ( MAC ) arthroscopic repair techniques . METHODS A prospect i ve , nonr and omized assessment of 132 arthroscopic rotator cuff repair patients included 78 SR repair patients and 54 with DR repair . Tears measured between 1.5 and 4.5 cm . Patients were evaluated with a visual analog scale ; University of California , Los Angeles score ; American Shoulder and Elbow Surgeons score ; active range of motion ; and dynamometric strength . Scores and measurements were obtained preoperatively and at 3 , 6 , 12 , and 24 months postoperatively . The SR repairs were performed with the arthroscopic MAC . For DR repairs , two 5.5-mm fully threaded Bio-Corkscrew anchors ( Arthrex , Naples , FL ) , single loaded with FiberWire ( Arthrex ) , were used for the medial row . The lateral row was secured with PushLock bioabsorbable anchors ( Arthrex ) . Forty-four patients in the SR group and 37 patients in the DR group returned for magnetic resonance imaging ( MRI ) evaluation of repair integrity between 12 and 28 months postoperatively . RESULTS DR repairs result ed in higher outcome scores , though not significantly . Patient satisfaction rates were 95 % in the SR group and 92 % in the DR group . MRI showed a statistically significantly improved healing rate with SR repair compared with DR repair in our entire patient population ( P ≤ .017 ) . A more homogeneous subset of patients with tears between 2.5 and 3.5 cm showed a significantly improved healing rate for the DR repair ( P ≤ .03 ) . CONCLUSIONS Our short-term results suggest that SR MAC repair provides comparable clinical results to DR repair . Although our MRI data suggest improved healing rates in our SR repairs in the entire patient population , when similar-sized tears were compared , the DR repair group showed improved radiographic healing . LEVEL OF EVIDENCE Level III , retrospective comparative study PURPOSE The purpose of this study was to compare the clinical outcomes and the retear rates of arthroscopic single-row ( SR ) and double-row ( DR ) suture anchor repair in 2- to 4-cm rotator cuff tears . METHODS From 2005 to 2007 , 71 patients with a 2- to 4-cm rotator cuff tear ( proven by arthroscopy ) were prospect ively r and omized to  SR  and DR repair groups . Of these patients , 62 ( 31 in each group ) were available for evaluation at final follow-up . Demographic data , clinical scores , mean surgical times , and patient satisfaction were compared . Retear rates and clinical scores were also analyzed for 47 patients who underwent follow-up magnetic resonance imaging .  RESULTS Comparisons of demographic data , tear size on preoperative magnetic resonance imaging , global fatty degeneration index , and concomitant procedures showed no differences between the SR and DR groups . Preoperative clinical scores were significantly improved postoperatively in both groups . No intergroup differences in pain visual analog scale , American Shoulder and Elbow Surgeons , Constant , or University of California , Los Angeles scores were found at final follow-up . Only mean surgical time was significantly different between the 2 groups . In the SR group , there were 4 full-thickness retears and 11 partial-thickness retears , whereas in the DR group , there were 6 full-thickness retears and 1 partial-thickness retear . However , despite numerical differences , these differences were not statistically different . Statistically , there were no significant differences both in full-thickness retear ( P = .999 ) and retear including partial-thickness tear between the 2 groups ( P = .124 ) . CONCLUSIONS This study indicates that the clinical results and retear rates of DR repair with 1 additional medial suture anchor were not significantly different from those of SR repairs with 2 lateral suture anchors in patients with medium to large rotator cuff tear . LEVEL OF EVIDENCE Level I , r and omized controlled trial PURPOSE To prospect ively compare therapeutic effect of femoral tunnel preparation through the tibial tunnel and the anteromedial ( AM ) portal in  single-bundle anterior cruciate ligament ( ACL ) reconstruction .  METHODS Between June 2008 and October 2010 , 76 patients underwent single-bundle ACL reconstruction by autogenous grafting of semitendinosus and gracilis tendon .  All cases were r and omly divided into two groups according to the method of femoral tunnel preparation : transtibial ( TT ) group ( n=38 ) and anteromedial ( AM ) group ( n=38 ) . Lysholm knee score and the KT-1000 anterior laxity at 30 ° of pre- and post-operation were assessed for two groups . RESULTS Sixty-five patients ( TT group , 34 ; AM group , 31 ) were followed up for more than 12 months , with a follow-up rate of 86 % . The Lysholm knee score and the KT-1000 anterior laxity 12 months after operation were significantly better than before reconstruction . The Lysholm knee score and the KT-1000 anterior laxity were not significantly different between the TT and AM groups after operation . CONCLUSION Femoral tunnel preparation through tibial tunnel or the anteromedial portal in single-bundle anterior cruciate ligament reconstruction shows same therapeutic effects PURPOSE The purpose of this study was to compare the clinical and imaging outcomes of single-row and double-row suture anchor fixation in  arthroscopic rotator cuff repair  with emphasis on analysis of the effect of various tear size on repair integrity . METHODS Fifty-three patents were r and omized to either single-row or double-row rotator cuff repair at the time of surgical intervention . The clinical results were evaluated by applying the UCLA score and the ASES index and assessing muscle strength in abduction and external rotation with a minimum 2-year follow-up . The postoperative rotator cuff integrity was evaluated by magnetic resonance arthrography at 6-month and minimum 2-year follow-up . RESULTS We enrolled 27 patients in the single-row group and 26 patients in the double-row group . Statistically , the UCLA score ; the ASES index ; and muscle strength were significantly increased in both groups after surgery , but there was no significant difference between the 2 groups . At minimum 2-year follow-up , intact rotator cuffs were found in 17 patients in the single-row group and 20 in the double-row group , based on magnetic resonance arthrography results . Overall , there was no significant difference in postoperative structural integrity between the 2 groups at 6-month and 2-year follow-up . In patients with tear size larger than 3 cm , the muscle strength of the shoulder was significantly better in the double-row group . For the final imaging results , regardless of the tear size , there was no difference between the single-row and double-row groups . CONCLUSIONS Ar 
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CONCLUSIONS According to this systematic review of overlapping meta-analyses comparing SR and DR RCR , the current highest level of evidence suggests that DR RCR provides superior structural healing to SR RCR .