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Yavuz Kocabey

Publications and source records attributed to Yavuz Kocabey.

At least 19 recordsLinked to original sources
PubMed2006

Pullout strength of meniscal repair after cyclic loading: comparison of vertical, horizontal, and oblique suture techniques.

This in vitro biomechanical study with cyclic loading compared the pullout strength of vertical, horizontal, and oblique sutures used for meniscal lesion repair. Following repair of vertical longitudinal lesions created in bovine medial menisci, three groups of seven specimens (vertical, horizontal, and oblique sutures) underwent cyclic loading in a randomized test order (5 mm/min, cycling between 5 and 50 N at 1 Hz for 100 cycles) prior to load to failure testing (5 mm/min). Displacement did not differ between groups during cyclic or load to failure testing. Construct stiffness during cyclic testing was superior for the oblique suture (6.9 +/- 1.5 N/mm, P = 0.007) and the vertical suture (6.4 +/- 7 N/mm, P = 0.03) groups compared to the horizontal suture group (4.4 +/- 0.52 N/mm). The oblique suture (171.9 +/- 25.9 N, P < 0.0001) and the vertical suture (145.9 +/- 32.3 N, P = 0.001) groups displayed superior load at failure compared to the horizontal suture group (88.8 +/- 8.2 N). Construct stiffness during load to failure testing did not differ between groups. Suture rupture was the failure mode for all specimens of the oblique suture group. Suture rupture was the failure mode for 57% (4/7) of the vertical suture group with the remaining specimens (3/7, 43%) failing from intact suture pullout through meniscal tissue. All horizontal suture group specimens failed by intact suture pulling through meniscal tissue. With comparable stiffness during cyclic testing, comparable load at failure as vertical sutures, and less evidence of intact suture pullout through the meniscus, an oblique suture technique may combine the beneficial characteristics of vertical (superior biomechanical strength) and horizontal (ease of application, longer sutures with a tendency to cover a larger meniscal tissue area) suture-repair techniques.

Animals↗
PubMed2006

A biomechanical comparison of the FasT-Fix meniscal repair suture system and the RapidLoc device in cadaver meniscus.

PURPOSE: This biomechanical study compared the fixation characteristics of horizontally or vertically implanted FasT-Fix devices (Smith & Nephew, Endoscopy Division, Andover, MA) consisting of two 5-mm PLLA suture T-bar anchors with a pretied self-sliding knot (No. 0 nonabsorbable, USP, braided polyester suture material) and the RapidLoc device (Mitek Surgical Products, Westwood, MA) consisting of a PLLA T-bar anchor or "backstop," a connecting suture (No. 2 nonbiodegradable Ethibond; Ethicon, Somerville, NJ), and a PLLA grommet, for repairing posterior third lesions in human menisci. TYPE OF STUDY: Controlled laboratory biomechanical study. METHODS: After repair of a vertical longitudinal meniscus lesion with either vertically or horizontally implanted FasT-Fix devices or RapidLoc devices, 3 groups of 6 specimens underwent cyclic loading (5 mm/minute, cycling between 5 and 50 N at 1 Hz for 500 cycles) before load to failure testing on a servo hydraulic device. One-way analysis of variance and Tukey HSD post hoc tests were used to evaluate group differences (P < .05). RESULTS: The vertical FasT-Fix device group (3.2 +/- 0.49 mm) had less displacement after cyclic testing than either the horizontal FasT-Fix (4.4 +/- 0.73 mm, P = .003) or the RapidLoc (4.6 +/- 0.22 mm, P = .002) device groups. The vertical FasT-Fix device group had greater stiffness during cyclic testing (14.4 +/- 2.1 N/mm) than the horizontal FasT-Fix (10.4 +/- 1.6 N/mm, P = .0001) or the RapidLoc (9.7 +/- 0.44 N/mm, P = .0001) device groups. During load to failure testing, the vertical FasT-Fix group (125.3 +/- 39 N) had 28% greater strength than the horizontal FasT-Fix device group (89.7 +/- 14 N, P = .02) and 30% greater strength than the RapidLoc device group (87.1 +/- 13 N, P = .028), whereas displacement and stiffness did not show statistically significant group differences. CONCLUSIONS: The vertical FasT-Fix group had superior biomechanical characteristics for meniscal fixation during cyclic and load to failure testing compared with horizontal FasT-Fix or RapidLoc devices. CLINICAL RELEVANCE: Although the RapidLoc devices provided fixation characteristics comparable to horizontally implanted FasT-Fix devices, vertically implanted FasT-Fix devices may provide superior all-inside fixation.

Absorbable Implants↗
PubMed2006

Self-reported patient outcomes at a minimum of 5 years after allograft anterior cruciate ligament reconstruction with or without medial meniscus transplantation: an age-, sex-, and activity level-matched comparison in patients aged approximately 50 years.

PURPOSE: Patient outcomes at a minimum of 5 years after medial meniscus transplantation and primary anterior cruciate ligament (ACL) reconstruction via allograft tissues were compared with those of age-, sex-, and activity level-matched patients who underwent meniscal repair or partial meniscectomy and primary ACL reconstruction via allograft tissues. METHODS: Eight patients (mean age, 51 +/- 5 years; three women and five men) at 5.5 +/- 0.5 years after medial meniscus transplantation and ACL reconstruction (group 1) and eight matched patients (mean age, 50 +/- 5 years; three women and five men) at 5.1 +/- 0.5 years after meniscal repair or partial meniscectomy and ACL reconstruction (group 2) completed the meniscus allograft clinical registry questionnaire, which combined the modified Lysholm knee scoring scale, the 1999 International Knee Documentation Committee subjective knee evaluation, and the knee pain level score on a 10-cm visual analog scale. RESULTS: Both groups displayed similar improvements in the modified Lysholm knee scoring scale components of pain, knee stability, squatting, stair climbing, and limping, as well as overall score (P < .05). Only group 2 displayed significant reductions in swelling. The groups displayed similar improvements in the 1999 International Knee Documentation Committee subjective knee evaluation components of sitting, rising from a chair, running, jumping, and stopping quickly, as well as overall score (P < .05). They also displayed significant improvements in the visual analog scale knee pain level score; however, group 1, which displayed greater preoperative pain levels, had considerably larger reductions. Most group 1 patients (7/8 [87.5%]) and all group 2 patients (8/8 [100%]) considered their surgery to be a success and would undergo the same procedure again if necessary. CONCLUSIONS: Although group 1 had greater preoperative knee pain levels, their pain levels at 5 years postoperatively were comparable to those in group 2. With the exception of swelling, comparable improvements were observed between groups for all other variables. LEVEL OF EVIDENCE: Level III, retrospective, case-control study.

Activities of Daily Living↗
PubMed2005

Comparison of volumetric bone mineral density in the tibial region of interest for ACL reconstruction.

Adequate tibial bone mineral density (BMD) is essential to soft tissue graft fixation during anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to compare volumetric bone plug density measurements at the tibial region of interest for ACL reconstruction using a standardized immersion technique and Archimedes' principle. Cancellous bone cores were harvested from the proximal, middle, and distal metaphyseal regions of the lateral tibia and from the standard tibial tunnel location used for ACL reconstruction of 18 cadaveric specimens. Proximal tibial cores displayed 32.6% greater BMD than middle tibial cores and 31.8% greater BMD than distal tibial cores, but did not differ from the BMD of the tibial tunnel cores. Correlational analysis confirmed that the cancellous BMD in the tibial tunnel related to the cancellous BMD of the proximal and distal lateral tibial metaphysis. In conjunction with its adjacent cortical bone, the cancellous BMD of the region used for standard tibial tunnel placement provides an effective foundation for ACL graft fixation. In tibia with poor BMD, bicortical fixation that incorporates cortical bone from the distal tibial tunnel region is recommended.

Aged↗
PubMed2005

Salvage rotator cuff repair using a biotenodesis screw.

Rotator cuff tear fixation can be difficult when humeral head bone stock is poor as a result of osteopenia or osteoporosis. This technical note describes biotenodesis screw use to achieve effective fixation after 2 previous attempts at implanting suture anchors failed.

Bone Screws↗
PubMed2005

Influence of thread design on bioabsorbable interference screw insertion torque during retrograde fixation of a soft-tissue graft in synthetic bone.

PURPOSE: Bioabsorbable interference screw design may influence biomechanical characteristics. This study compared the insertion torque and load at failure characteristics of 2 types of screws during retrograde fixation of a soft-tissue graft. TYPE OF STUDY: Biomechanical study. METHODS: Eight matched pairs of doubled 100-mm long tibialis anterior allografts were prepared and fixed in appropriately sized tunnels created in 10 lb/ft 3 (0.16 g/cm3) dense synthetic bone blocks using screws of similar length and root and thread diameter designed with either a large buttress thread with a smaller taper or small buttress thread with a larger taper. Insertion torque was measured at one-third, two-thirds, and full screw insertion. After the graft fixation constructs were mounted in a servohydraulic-testing device with the loading axis aligned directly with the tunnel and preloaded to 25 N, they were cycled 3 times from 0 to 50 N, and then subjected to a 20 mm/minute traction force to failure. RESULTS: All constructs failed by graft slippage past the screw. Mean maximum load at failure (360.5 +/- 68 N v 341.6 +/- 58 N, P = .2) and stiffness (63.6 +/- 16 N/mm 2 v 66.4 +/- 14 N/mm 2 , P = .89) was similar between constructs fixed with a large buttress thread small-taper screw and small buttress thread large-taper screw, respectively. The small buttress thread screw with a large taper displayed greater mean insertion torque at one-third insertion (4.1 +/- 0.57 in-lb v 3.2 +/- 0.49 in-lb, P = .03), whereas the large buttress thread screw with a small taper displayed greater mean insertion torque at full insertion (11.1 +/- 0.74 in-lb v 9.4 +/- 1.3 in-lb, P = .012). Mean differences were not observed at two-thirds screw insertion (P = .12). CONCLUSIONS: Large buttress thread small-taper screws displayed biomechanical fixation characteristics comparable to small buttress thread large-taper screws. CLINICAL RELEVANCE: Given reports of superior screw-graft-bone tunnel contact area, these biomechanical results suggest that use of a large buttress screw with a small taper may be preferable for retrograde soft-tissue graft fixation.

Absorbable Implants↗
PubMed2005

Anatomy, function, and rehabilitation of the popliteus musculotendinous complex.

We present a clinical commentary of existing evidence regarding popliteus musculotendinous complex anatomy, biomechanics, muscle activation, and kinesthesia as they relate to functional knee joint rehabilitation. The popliteus appears to act as a dynamic guidance system for monitoring and controlling subtle transverse- and frontal-plane knee joint movements, controlling anterior-posterior lateral meniscus movement, unlocking and internally rotating the knee joint (tibia) during flexion initiation, assisting with 3-dimensional dynamic lower extremity postural stability during single-leg stance, preventing forward femoral dislocation on the tibia during flexed-knee stance, and providing for postural equilibrium adjustments during standing. These functions may be most important during mid-range knee flexion when capsuloligamentous struCtures are unable to function optimally. Because the popliteus musculotendinous complex has attachments that approximate the borders of both collateral ligaments, it has the potential for providing instantaneous 3-dimensional kinesthetic feedback of both medial and lateral tibiofemoral joint compartment function. Enhanced popliteus function as a kinesthetic knee joint monitor acting in synergy with dynamic hip muscular control of femoral internal rotation and adduction, and ankle subtalar muscular control of tibial abduction-external rotation or adduction-internal rotation, may help to prevent athletic knee joint injuries and facilitate recovery during rehabilitation by assisting the primary sagittal plane dynamic knee joint stabilization provided by the quadriceps femoris, hamstrings, and gastrocnemius.

Biomechanical Phenomena↗
PubMed2005

[The results of open surgical treatment in patients with chronic refractory lateral epicondylitis].

OBJECTIVES: We evaluated the clinical and subjective functional results of open surgical treatment in patients with chronic refractory lateral epicondylitis. METHODS: Eleven patients (7 females, 4 males; mean age 42 years, range 29 to 56 years) underwent open surgical treatment for chronic refractory lateral epicondylitis. All the patients had received conservative treatment for at least a year without favorable response. Surgical procedure included release of the lateral extensor origin, excision of the degenerative tissue, decortication or drilling of the anterior lateral condyle, and repair of the extensor tendons. The results were evaluated according to the criteria proposed by Verhaar et al. The mean follow-up was 29 months (range 18 to 45 months). RESULTS: The results were excellent or good in 10 patients (90.9%) and acceptable in one patient (9.1%). The mean time to return to work was two months. Nine patients were free of pain in the forearm in the postoperative third month. No wound-related complications were encountered. On subjective evaluations, 10 patients reported full satisfaction, and one patient reported partial satisfaction with the result of the treatment. CONCLUSION: Open surgical procedure including release of the origins of the common extensor tendons and excision of the degenerative tissue yields favorable results in the treatment of patients with chronic refractory lateral epicondylitis.

Adult↗
PubMed2005

[The effect of the tibial tunnel fixation level on the results of cyclic loading in anterior cruciate ligament reconstruction].

OBJECTIVES: This study was designed to compare the biomechanical characteristics of non-anatomic (far from joint) and anatomic (close to joint) levels of tibial tunnel fixation with soft tissue graft using a soft tissue interference screw in anterior cruciate ligament (ACL) reconstruction. METHODS: Twelve bovine tibiae and digital extensor tendons were divided into two homogeneously equal groups after removing soft tissues. Tibial tunnels were prepared with a 7-mm drill with the use of an ACL guide adjusted to 45 degrees . Each tunnel was then dilated to 9 mm in 0.5 mm increments. Digital extensor tendons were fixed at non-anatomic (group I) or anatomic (group II) tibial tunnel levels with a soft tissue metal interference screw, 9 x 30 mm in size. All the specimens were cycled 500 times from 50 to 250 N with 1 Hz frequency in a servo-hydraulic testing machine followed by ultimate load at-failure testing at a rate of 20 mm/min. Statistical analyses were made using the Mann-Whitney U-test. RESULTS: The mean screw insertion torque values were 8.2+/-2.4 Nm and 7.8+/-2.3 Nm in groups I and II, respectively (p=0.88). The mean values of graft displacement (1.9+/-0.75 mm versus 2.2+/-1.2 mm, p=0.63) and stiffness (132.72+/-10.93 N/mm versus 125.14+/-15.93 N/mm, p=0.63) did not differ significantly. CONCLUSION: The biomechanical properties of ACL reconstruction with soft tissue graft fixation using a soft tissue interference screw are not influenced by the level of tibial tunnel fixation.

Absorbable Implants↗
PubMed2005

[The effect of anterior or posterior tibial tunnel placement of a soft tissue graft with a soft tissue interference screw on fixation biomechanics].

OBJECTIVES: We investigated the biomechanical characteristics of anterior or posterior tibial tunnel placement of the soft tissue graft with a soft tissue interference screw in anterior cruciate ligament (ACL) reconstruction. METHODS: Twelve bovine tibiae and digital extensor tendons were divided into two homogeneously equal groups after they were stripped of all soft tissues. Tibial tunnels were prepared and digital extensor tendons were fixed at nonanatomic (apart from the joint) anterior (n=6, group I) or posterior (n=6, group II) tibial tunnel positions with a soft tissue metal interference screw, 9x30 mm in size. All the specimens were cycled 500 times from 50 to 250 N at 1 Hz frequency in a servo hydraulic test device, after which ultimate load-at-failure testing was performed at a rate of 20 mm/min. RESULTS: The mean screw insertion torque values were 8.2+/-2.4 Nm and 8.4+/-2.8 Nm in groups I and II, respectively (p=0.88). No significant differences were found between the two groups with respect to graft displacement (1.9+/-0.8 mm vs 2.3+/-0.4 mm; p=0.38) and stiffness (132.7+/-10.9 N/mm vs 126.4+/-8.5 N/mm, p=0.98) at the end of cyclic loading. CONCLUSION: Our results show that the site of nonanatomic soft tissue graft fixation in the tibial tunnel (anterior or posterior) with a soft tissue interference screw do not affect the biomechanical parameters in ACL reconstruction.

Animals↗
PubMed2004

Patient outcomes following T-Fix meniscal repair and a modifiable, progressive rehabilitation program, a retrospective study.

INTRODUCTION: This retrospective study presents clinical patient outcomes following meniscal repair using T-Fix devices and a modifiable, progressive rehabilitation program. MATERIALS AND METHODS: Fifty-two patients (35 males and 17 females) with a mean age of 26.7 years (range 13-50 years) representing all of the patients who underwent arthroscopic meniscal repair (43 medial meniscus, 12 lateral meniscus) over a 3-year period by the same surgeon (D.C.) (55 menisci) participated in this study. Thirty-two of the patients (62%) had an associated ACL tear. All patients with an ACL tear underwent reconstruction (tibialis anterior allograft) at the time of meniscal repair. All meniscal tears were located in either the red-red zone (29) or the red-white zone (26). All patients who underwent meniscal repair participated in a modifiable (based on meniscal tear size, type, and location) progressive rehabilitation program. Operative notes and photographs were reviewed to identify the meniscal tear location, tear type, tear length, and the number of T-Fix devices used. Orthopedic clinic and physical therapy reports were also reviewed for postoperative range of motion, knee joint effusion, knee joint pain, McMurray test findings, and single-leg broad-jump test performance (90% bilateral equivalence goal). The average postoperative clinical follow-up period was 10.3 months (range 4-24 months). RESULTS: Most (22/23, 96%) patients who underwent meniscal repair alone displayed excellent results. All patients (32/32, 100%) who underwent combined ACL reconstruction-meniscal repair displayed excellent results. During an acute event such as a sudden directional change while running or contact with another player, 5 of these patients re-injured their meniscus at the repair site in conjunction with tearing the reconstructed ACL at 12+/-3 months following the index surgical procedure. Each of these 1-2 cm meniscal tears had been previously repaired with two T-Fix devices. CONCLUSION: The T-Fix device used in combination with a modifiable progressive rehabilitation program produced excellent clinical patient outcomes among this patient group.

Adolescent↗
PubMed2004

Insertion torque pullout strength relationship of soft tissue tendon graft tibia tunnel fixation with a bioabsorbable interference screw.

PURPOSE: The purpose of this study was to evaluate the relationship between insertion torque and the biomechanical characteristics of soft tissue tendon graft tibia fixation with a bioabsorbable interference screw. TYPE OF STUDY: Biomechanical study. METHODS: Doubled tibialis anterior allografts (n = 20, length = 100 mm, diameter = 9 mm) prepared for anterior cruciate ligament (ACL) reconstructions were divided into 3 groups. Maximum insertion torque was measured as grafts were fixed by the same surgeon with a 10-mm diameter, 35-mm long screw in a 7-mm diameter tunnel (dilated to 9 mm) created in either 0.16 or 0.32 g/cm3 dense synthetic bone or cadaveric tibiae (0.84 +/- 0.15 g/cm2). Tensile testing to construct failure was then performed. RESULTS: All constructs failed by tunnel pullout. Higher density synthetic bone had greater load at failure than lower density synthetic bone (486.6 +/- 83.8 v 271.6 +/- 52.6 N, P <.0001) and a slightly greater proportion of variance could be explained in synthetic bone (R2 = 0.74, P <.0001) than in cadaveric tibiae (R2 = 0.64, P =.017). Higher density synthetic bone displayed greater stiffness than lower density synthetic bone (68.1 +/- 21.6 v 37.7 +/- 11.2 N/mm, P =.012) and a higher proportion of variance could be explained in cadaveric tibiae (R2 = 0.72, P =.008) than in synthetic bone (R2 = 0.48, P =.012). Greater insertion torque levels were seen in higher density synthetic bone (2.97 +/- 0.35 v 1.24 +/- 0.06 Nm, P <.0001) than in lower density synthetic bone, and a higher proportion of variance could be explained in synthetic bone (R2 = 0.94, P <.0001) than in cadaveric tibiae (R2 = 0.74, P =.006). CONCLUSIONS: Strong relationships were evident between insertion torque, bone mineral density (BMD) and load to failure across constructs. Differences between the synthetic bone groups and cadaveric tibiae, however, suggest the influence of mixed cortical and cancellous bone, nonuniform structural patterning, and differing BMD levels and distributions in the cadaveric tibiae. CLINICAL RELEVANCE: Soft tissue graft tibial tunnel fixation is directly related to insertion torque and BMD. Synthetic models with mixed bone characteristics are needed to more accurately depict human tibiae during fixation testing.

Absorbable Implants↗
PubMed2004

Posterolateral corner reconstruction using a hamstring allograft and a bioabsorbable tenodesis screw: description of a new surgical technique.

Capsuloligamentous posterolateral corner knee joint deficiencies cause increased anterior cruciate ligament forces during internal knee rotation and increased posterior cruciate ligament forces during external knee rotation. Undiagnosed posterolateral corner knee joint injury in combination with anterior cruciate ligament or posterior cruciate ligament injury can lead to failure of anterior cruciate ligament or posterior cruciate ligament reconstruction. The purpose of this technical note is to present a new posterolateral corner reconstruction technique for treating patients with chronic capsuloligamentous posterolateral corner deficiency. The technique uses a bioabsorbable tenodesis screw and a hamstring allograft to reconstruct the popliteofibular and lateral collateral ligaments.

Absorbable Implants↗
PubMed2004

The value of clinical examination versus magnetic resonance imaging in the diagnosis of meniscal tears and anterior cruciate ligament rupture.

PURPOSE: The purpose of this study was to compare the accuracy of clinical examination versus magnetic resonance imaging (MRI) in diagnosing meniscal and anterior cruciate ligament (ACL) pathology. TYPE OF STUDY: Prospective, longitudinal study. METHODS: Between August 2001 and December 2001, we prospectively evaluated 50 consecutive patients (37 male, 13 female) with 65 pathologies of medial meniscal tears, lateral meniscal tears, and/or ACL rupture. The average preoperative period for the patients was 5 weeks (range, 5 days to 5 months) and their mean age was 22 years (range, 12 to 42 years). After initial clinical examination, the same sports medicine fellowship-trained orthopaedic surgeon (10-year practice profile of 100% sports medicine) evaluated the MRI of the patients and performed their arthroscopic procedure. Accuracy, sensitivity, specificity, and positive and negative predictive values were calculated comparing clinical examination, MRI, and arthroscopic evaluation. RESULTS: There was no statistical difference between MRI or clinical examination in diagnosing medial or lateral meniscal tears or ACL tears ( P >.05). The accuracy of the clinical examination and MRI evaluation was equal for diagnosing meniscal tears and ACL ruptures. CONCLUSIONS: A well-trained qualified surgeon can safely rely on clinical examination for diagnosing meniscal and ACL injuries. Clinical examination is at least as accurate as MRI in the skilled orthopaedic surgeon's hand. MRI should be reserved for more complicated and confusing cases. The routine ordering of an MRI scan of the knee before examination by a well-trained orthopaedic surgeon is not recommended. LEVEL OF EVIDENCE: Level II, diagnostic.

Adolescent↗
PubMed2004

Tendon graft fixation in ACL reconstruction: in vitro evaluation of bioabsorbable tenodesis screw.

BACKGROUND: Conventional ACL reconstruction requires sufficient tibial bone quality for secure graft fixation. We evaluated the mechanical characteristics of a supplemental tenodesis screw in cadaveric specimens. MATERIAL AND METHODS: One group of 7 specimens from 7-paired tibiae was randomly assigned to undergo tibialis anterior tendon graft-bone tunnel fixation with a bioabsorbable interference screw, using conventional ACL reconstruction techniques. The other group of 7 specimens underwent the same procedure supplemented with a bioabsorbable tenodesis screw. All specimens were subjected to pullout testing on a servo hydraulic device. RESULTS: Specimens in the supplemental fixation group had double the load to failure (tenodesis = 467 (SD 184) N, control group = 223 (SD 66) N, p = 0.02) and were also one-third stiffer (tenodesis = 31 (SD 13) N/mm, control group = 21 (SD 6) N/mm, p = 0.03) than the specimens in the conventional fixation group. INTERPRETATION: Supplemental bioabsorbable tenodesis screw fixation may be advantageous for primary reconstruction in patients with low tibial bone mineral density or during revision procedures. By providing secure soft tissue graft-tibia fixation during the early phase after ACL reconstruction, supplemental tenodesis fixation may enable patients to participate safely in more intense, early rehabilitation.

Absorbable Implants↗
PubMed2004

A biomechanical comparison of initial soft tissue tibial fixation devices: the Intrafix versus a tapered 35-mm bioabsorbable interference screw.

BACKGROUND: Biomechanical testing of the Intrafix device has not been performed using human tibiae. HYPOTHESIS: The Intrafix device would provide comparable or superior tibial fixation of a quadrupled hamstring tendon graft to a 35-mm-long bioabsorbable interference screw. STUDY DESIGN: In vitro, biomechanical study. METHODS: Eight paired human tibiae and 16 quadrupled hamstring tendon grafts were divided into 2 groups. Each quadrupled hamstring tendon graft was fixed in a tunnel sized to 0.5 mm graft diameter with either an Intrafix device or a screw. RESULTS: Displacement at failure was greater in the Intrafix group (17.3 +/- 4.6 mm versus 10.9 +/- 4.4 mm, P =.002). Load at failure (796 +/- 193 N versus 647 +/- 269 N), stiffness (49.2 +/- 21.9 N/mm versus 64.5 +/- 22 N/mm), and bone mineral density (0.74 +/- 0.15 gm/cm(3) versus 0.74 +/- 0.14 gm/cm(3)) did not display significant differences for the Intrafix device and the screw, respectively (P >.05). CONCLUSIONS: Displacement at failure was greater for the Intrafix device. CLINICAL RELEVANCE: Increased displacement at failure for the Intrafix group suggests slippage from sheath channel deployment. Concentric fixation may not occur when less than optimal tibial bone mineral density increases the difficulty of attaining precise sheath deployment and quadrupled hamstring tendon graft strand alignment.

Bone Screws↗
PubMed2004

Sex differences in perceived importance of hamstring stretching among high school athletes.

Adolescent athletes completed a hamstring stretching technique and opinion survey and were measured for hamstring extensibility during preparticipation examination. Hamstring muscle group stretching practices, extensibility, and perception of importance to injury prevention, athletic performance, warming-up, cooling down, and coaches were contrasted by sex. As expected, girls displayed greater hamstring muscle group flexibility than boys. Boys and girls reported similar hamstring stretch repetitions and stretch duration. Boys scored hamstring stretching as being more important to improved athletic performance and to their coaches than did girls. Differences were not evident between groups for prevention of injury, warm-up, or cool-down. The lower perception of hamstring stretching importance for improving athletic performance and a lesser perception of hamstring stretching importance to their coaches suggests that adolescent female athletes and their coaches may not fully understand the value of static hamstring stretching. Modified hamstring stretching technique may selectively increase hamstring extensibility among girls without contributing to increasing capsuloligamentous knee joint laxity.

Adolescent↗