A Comparative Biomechanical Analysis of 2 Double-Row, Distal Triceps Tendon Repairs

Background: Triceps tendon ruptures are rare orthopaedic injuries that almost always require surgical repair. This study tests the biomechanical properties of an original anchorless double-row triceps repair against a previously reported knotless double-row repair. Hypothesis: The anchorless double-row triceps repair technique will yield similar biomechanical properties when compared with the knotless double-row repair technique. Study Design: Controlled laboratory study. Methods: Eighteen cadaver arms were randomized into 2 groups. One group received the anchorless repair and the other received the knotless anchor repair. A materials testing system (MTS) machine was used to cycle the repaired arms from 0° to 90° with a 2.5-pound weight for 1500 cycles at 0.25 Hz. Real-time displacement of the tendon was measured during cycling using a probe. Load to failure was performed after completion of cyclic loading. Results: The mean displacement with the anchorless technique was 0.77 mm (SD, 0.25 mm) at 0° (full elbow extension) and 0.76 mm (SD, 0.38 mm) at 90° (elbow flexion). The mean displacement with the anchored technique was 0.83 mm (SD, 0.57 mm) at 0° and 1.01 mm (SD, 0.62 mm) at 90°. There was no statistically significant difference for tendon displacement at 0º ( P = .75) or 90º ( P = .31). The mean load to failure with the anchorless technique was 618.9 N (SD, 185.6 N), while it was 560.5 N (SD, 154.1 N) with the anchored technique, again with no statistically significant difference ( P = .28). Conclusion: Our anchorless double-row triceps repair technique yields comparable biomechanical properties to previously described double-row triceps tendon repair techniques, with the added benefit of avoiding the cost of suture anchors. Clinical Relevance: This anchorless double-row triceps tendon repair can be considered as an acceptable alternative to a knotless anchor repair for triceps tendon ruptures.

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The V-Shaped Distal Triceps Tendon Repair: A Comparative Biomechanical Analysis

The American Journal of Sports Medicine ◽

10.1177/0363546518771359 ◽

2018 ◽

Vol 46 (8) ◽

pp. 1952-1958 ◽

Cited By ~ 3

Author(s):

Bastian Scheiderer ◽

Florian B. Imhoff ◽

Daichi Morikawa ◽

Lucca Lacheta ◽

Elifho Obopilwe ◽

...

Keyword(s):

Failure Load ◽

Tendon Repair ◽

Biomechanical Analysis ◽

Gap Formation ◽

Suture Bridge ◽

Repair Technique ◽

Significant Difference ◽

Load To Failure ◽

Triceps Tendon ◽

Insertion Area

Background: Restoring footprint anatomy, minimizing gap formation, and maximizing the strength of distal triceps tendon repairs are essential factors for a successful healing process and return to sport. Hypothesis: The novel V-shaped distal triceps tendon repair technique with unicortical button fixation closely restores footprint anatomy, provides minimal gap formation and high ultimate failure load, and minimizes iatrogenic fracture risk in acute/subacute distal triceps tendon tears. Study Design: Controlled laboratory study. Methods: Twenty-four cadaveric elbows (mean ± SD age, 66 ± 5 years) were randomly assigned to 1 of 3 repair groups: the transosseous cruciate repair technique (gold standard), the knotless suture-bridge repair technique, and the V-shaped distal triceps tendon repair technique. Anatomic measurements of the central triceps tendon footprint were obtained in all specimens with a 3-dimensional digitizer before and after the repair. Cyclic loading was performed for a total of 1500 cycles at a rate of 0.25 Hz, pulling in the direction of the triceps. Displacements were measured on the medial and lateral tendon sites with 2 differential variable reluctance transducers. Load to failure and construct failure mode were recorded. Results: The mean triceps bony insertion area was 399.05 ± 81.23 mm2. The transosseous cruciate repair technique restored 36.6% ± 16.8% of the native tendon insertion area, which was significantly different when compared with the knotless suture-bridge repair technique (85.2% ± 14.8%, P = .001) and the V-shaped distal triceps tendon repair technique (88.9% ± 14.8%, P = .002). Mean displacement showed no significant difference between the V-shaped distal triceps tendon repair technique (medial side, 0.75 ± 0.56 mm; lateral side, 0.99 ± 0.59 mm) and the knotless suture-bridge repair technique (1.61 ± 0.97 mm and 1.29 ± 0.8 mm) but significance between the V-shaped distal triceps tendon repair technique and the transosseous cruciate repair technique (4.91 ± 1.12 mm and 5.78 ± 0.9 mm, P < .001). Mean peak failure load of the V-shaped distal triceps tendon repair technique (732.1 ± 156.0 N) was significantly higher than that of the knotless suture-bridge repair technique (505.4 ± 173.9 N, P = .011) and the transosseous cruciate repair technique (281.1 ± 74.8 N, P < .001). Mechanism of failure differed among the 3 repairs, with the only olecranon fracture occurring in the knotless suture-bridge repair technique at the level of the lateral row suture anchors. Conclusion: At time zero, the V-shaped distal triceps tendon repair technique and the knotless suture-bridge repair technique both provided anatomic footprint coverage. Ultimate load to failure was highest for the V-shaped distal triceps tendon repair technique, while gap formation was different only in comparison with the transosseous cruciate repair technique. Clinical Relevance: The V-shaped distal triceps tendon repair technique provides an alternative procedure to other established repairs for acute/subacute distal triceps tendon ruptures. The reduced repair site motion of the V-shaped distal triceps tendon repair technique and the knotless suture-bridge repair technique at the time of surgery may allow a more aggressive rehabilitation program in the early postoperative period.

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A unique case of bilateral triceps avulsion fracture in a patient with pseudohypoparathyroidism

Shoulder & Elbow ◽

10.1177/1758573219876553 ◽

2019 ◽

pp. 175857321987655

Author(s):

Ali-Asgar Najefi ◽

Peter Domos

Keyword(s):

Avulsion Fracture ◽

Unique Case ◽

Double Row ◽

Avulsion Fractures ◽

Unique Method ◽

Tendon Ruptures ◽

Triceps Tendon ◽

Double Row Repair ◽

Suture Anchor Fixation ◽

Anchor Fixation

Triceps tendon ruptures and avulsions are rare injuries and are often associated with systemic diseases. This paper illustrates the unique case of a 20-year-old female patient with pseudohypoparathyroidism, who sustained bilateral triceps avulsion fractures after a fall. She underwent suture anchor fixation, augmented with tension band suture as double row repair with excellent post-operative results. We describe the pathophysiology of this injury and the unique method of fixation, which can be an alternative effective method to repair these injuries.

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Distal Triceps Tendon Injury

Video Journal of Sports Medicine ◽

10.1177/26350254211044504 ◽

2022 ◽

Vol 2 (1) ◽

pp. 263502542110445

Author(s):

John R. Matthews ◽

Ryan W. Paul ◽

Kevin B. Freedman

Keyword(s):

Tendon Repair ◽

Eccentric Contraction ◽

Tendon Injury ◽

Acute Onset ◽

Gap Formation ◽

Double Row ◽

Highly Active ◽

Left Posterior ◽

Tendon Ruptures ◽

Triceps Tendon

Background: Triceps tendon ruptures typically result from a forceful elbow eccentric contraction. The goal of a distal triceps tendon repair is to reattach the torn tendon back to the olecranon. Surgery is indicated for patients with complete rupture of the triceps tendon or symptomatic partial tears with failed conservative management. The complication rate occurs in 22% of patients postoperatively; however, only 0% to 4% of patients suffer a re-rupture of the tendon. Indications: We present a case of a highly active 38-year-old right-hand dominant man with acute onset of left posterior elbow pain following 1-handed pushup resulting in a complete distal triceps avulsion with 1.5 cm retraction. Technique: The distal triceps avulsion was repaired in a double row fashion using 2 double-loaded all-suture anchors in the medial row and anchor in the lateral row through a posterior approach. Results: Full anatomic footprint coverage was able to be achieved intraoperatively, and gentle range of motion from 0 to 90 degrees of flexion did not result in gap formation. Discussion/Conclusion: Successful outcomes with full anatomic footprint coverage of the distal triceps tendon can be achieved through a double row repair configuration.

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Biomechanical Head-to-Head Comparison of 2 Sutures and the Giftbox Versus Bunnell Techniques for Midsubstance Achilles Tendon Ruptures

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967117707477 ◽

2017 ◽

Vol 5 (5) ◽

pp. 232596711770747 ◽

Cited By ~ 8

Author(s):

Rufus O. Van Dyke ◽

Sejul A. Chaudhary ◽

Gregory Gould ◽

Roman Trimba ◽

Richard T. Laughlin

Keyword(s):

Cyclic Loading ◽

Achilles Tendon ◽

Biomechanical Testing ◽

Gap Formation ◽

Postoperative Rehabilitation ◽

Repair Technique ◽

Significant Difference ◽

Load To Failure ◽

Tendon Ruptures ◽

To Receive

Background: Acute midsubstance Achilles tendon ruptures are a common orthopaedic problem for which the optimal repair technique and suture type remain controversial. Head-to-head comparisons of current fixation constructs are needed to establish which stitch/suture combination is most biomechanically favorable. Hypothesis: Of the tested fixation constructs, Giftbox repairs with Fiberwire will exhibit superior stiffness and strength during biomechanical testing. Study Design: Controlled laboratory study. Methods: Two biomechanical trials were performed, isolating stitch technique and suture type, respectively. In trial 1, 12 transected fresh-frozen cadaveric Achilles tendon pairs were randomized to receive either the Giftbox-modified Krackow or the Bunnell stitch with No. 2 Fiberwire suture. Each repair underwent cyclic loading, oscillating between 10 and 100 N at 2 Hz for 1000 cycles, with repair gapping measured at 500 and 1000 cycles. Load-to-failure testing was then performed, and clinical and catastrophic failure values were recorded. In trial 2, 10 additional paired cadaveric Achilles tendons were randomized to receive a Giftbox repair with either No. 2 Fiberwire or No. 2 Ultrabraid. Testing and data collections protocols in trial 2 replicated those used in trial 1. Results: In trial 1, the Bunnell group had 2 failures during cyclic loading while the Giftbox had no failures. The mean tendon gapping after cyclic loading was significantly lower in the Giftbox repairs (0.13 vs 2.29 mm, P = .02). Giftbox repairs were significantly stiffer than Bunnell (47.5 vs 38.7 N/mm, P = .019) and showed more tendon elongation (5.9 ± 0.8 vs 4.5 ± 1.0 mm, P = .012) after 1000 cycles. Mean clinical load to failure was significantly higher for Giftbox repairs (373 vs 285 N, P = .02), while no significant difference in catastrophic load to failure was observed (mean, 379 vs 336 N; P = .61). In trial 2, there were no failures during cyclic loading. The Giftbox + Fiberwire repairs recorded higher clinical load-to-failure values compared with Giftbox + Ultrabraid (mean, 361 vs 239 N; P = .005). No other biomechanical differences were observed in trial 2. Conclusion: Simulated early rehabilitation biomechanical testing showed that Giftbox-modified Krackow Achilles repair technique with Fiberwire suture was stronger and more resistant to gap formation at the repair site than combinations that incorporated the Bunnell stitch or Ultrabraid suture. Clinical Relevance: A more in-depth understanding of the biomechanical properties of the Giftbox repair will help inform surgical decision making because stronger repairs are less likely to fail during accelerated postoperative rehabilitation.

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Braided tape is equivalent to modified Mason-Allen multi-strand #2 suture in subscapularis muscle repair: results of a biomechanical study

Shoulder & Elbow ◽

10.1177/1758573216679945 ◽

2016 ◽

Vol 9 (2) ◽

pp. 85-91

Author(s):

Benjamin Léger-St-Jean ◽

Jérémie Ménard ◽

Stéphanie Hinse ◽

Frédéric Balg ◽

Dominique M Rouleau

Keyword(s):

Cyclic Loading ◽

Ultimate Load ◽

Tendon Repair ◽

Biomechanical Study ◽

Fixation Method ◽

Subscapularis Tendon ◽

Mineral Density ◽

Significant Difference ◽

Load To Failure ◽

The Mean

Background To help determine the optimal fixation method for subscapularis tendon repair in arthroplasty, the present study compares single-passage transosseous tape (BT) and modified Mason-Allen #2 suture (MA). Methods Eighteen human cadaveric shoulders were randomized to two repair constructs after arthroplasty preparation. Both techniques included two transosseous passages through the bicipital groove and then through the tendon at the level of the anatomical neck. Construct was tested using a traction machine, measuring cyclic loading and ultimate load to failure. Results The mean age of our specimens was 71 years. No significant difference was observed between the repair techniques in both mean ultimate load and cyclic loading. The mean (SD) ultimate load (UL) for BT was 293 (84) N and 342 (117) N for MA, which was not statistically significant ( p = 0.374). The majority of repairs failed in the tendon. Bone cut-out was observed with the MA but not for the BT repair. No correlation was found between bone density and UL for BT ( r = −0.09) but there was strong correlation for MA ( r = 0.63). Conclusions The MA repair appears to be more dependant on bone mineral density for ultimate load, indicating that braided-tape might be better suited for osteoporotic patients to avoid bone cut-out.

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Augmentation of Distal Biceps Repair With an Acellular Dermal Graft Restores Native Biomechanical Properties in a Tendon-Deficient Model

The American Journal of Sports Medicine ◽

10.1177/0363546517701426 ◽

2017 ◽

Vol 45 (9) ◽

pp. 2028-2033 ◽

Cited By ~ 5

Author(s):

Christine Conroy ◽

Paul Sethi ◽

Craig Macken ◽

David Wei ◽

Marc Kowalsky ◽

...

Keyword(s):

Biceps Tendon ◽

Peak Load ◽

Tendon Repair ◽

Biomechanical Properties ◽

Gap Formation ◽

Dermal Graft ◽

Distal Biceps ◽

Load To Failure ◽

The Mean ◽

Acellular Dermal

Background: The majority of distal biceps tendon injuries can be repaired in a single procedure. In contrast, complete chronic tears with severe tendon substance deficiency and retraction often require tendon graft augmentation. In cases with extensive partial tears of the distal biceps, a human dermal allograft may be used as an alternative to restore tendon thickness and biomechanical integrity. Hypothesis: Dermal graft augmentation will improve load to failure compared with nonaugmented repair in a tendon-deficient model. Study Design: Controlled laboratory study. Methods: Thirty-six matched specimens were organized into 1 of 4 groups: native tendon, native tendon with dermal graft augmentation, tendon with an attritional defect, and tendon with an attritional defect repaired with a graft. To mimic a chronic attritional biceps lesion, a defect was created by a complete tear, leaving 30% of the tendon’s width intact. The repair technique in all groups consisted of cortical button and interference screw fixation. All specimens underwent cyclical loading for 3000 cycles and were then tested to failure; gap formation and peak load at failure were documented. Results: The mean (±SD) load to failure (320.9 ± 49.1 N vs 348.8 ± 77.6 N, respectively; P = .38) and gap formation (displacement) (1.8 ± 1.4 mm vs 1.6 ± 1.1 mm, respectively; P = .38) did not differ between the native tendon groups with and without graft augmentation. In the tendon-deficient model, the mean load to failure was significantly improved with graft augmentation compared with no graft augmentation (282.1 ± 83.8 N vs 199.7 ± 45.5 N, respectively; P = .04), while the mean gap formation was significantly reduced (1.2 ± 1.0 mm vs 2.7 ± 1.4 mm, respectively; P = .04). The mean load to failure of the deficient tendon with graft augmentation (282.1 N) compared with the native tendon (348.8 N) was not significantly different ( P = .12). This indicates that the native tendon did not perform differently from the grafted deficient tendon. Conclusion: In a tendon-deficient, complete distal biceps rupture model, acellular dermal allograft augmentation restored the native tendon’s biomechanical properties at time zero. The grafted tissue-deficient model demonstrated no significant differences in the load to failure and gap formation compared with the native tendon. As expected, dermal augmentation of attritional tendon repair increased the load to failure and stiffness as well as decreased displacement compared with the ungrafted tissue-deficient model. Tendons with their native width showed no statistical difference or negative biomechanical consequences of dermal augmentation. Clinical Relevance: Dermal augmentation of the distal biceps is a biomechanically feasible option for patients with an attritionally thinned-out tendon.

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What is the relationship with rotator cuff tear size of the double row suture bridge transosseous equivalent repair technique?

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967117s00059 ◽

2017 ◽

Vol 5 (2_suppl2) ◽

pp. 2325967117S0005

Author(s):

Hakan Tırın ◽

Murat Gülçek

Keyword(s):

Rotator Cuff ◽

Rotator Cuff Tear ◽

Rotator Cuff Tears ◽

Double Row ◽

Cuff Tear ◽

Repair Technique ◽

Significant Difference ◽

Group 2 ◽

Double Row Repair ◽

Group 1

Background: Rotator cuff tears have an adverse effect on daily activities in personal disability and functional restriction. A few clinical studies have demonstrated the structural superiority of the double row technique. The aim of our study 3 cm below and the top of the rotator cuff tears and a double row repair technique with the results of the retrospectively our patients treated by comparing the results of double row repair techniques to understand the relationship between the tear size. Methods: In this retrospective study, and the data of patients who underwent arthroscopic rotator cuff repair in the years 2011-2014 were scanned as a single center. Inclusion criteria:1)3 cm above and below the rotator cuff tear preoperative identified by MRI imaging and confirmed by arthroscopy,2)which is operated by a double row repair techniques 3)do not benefit from conservative treatment 4)before patients are no operation history. Exclusion criteria: 1)partial tears, 2)irrepereabl tears, 3)arthritis in the shoulder x-ray, 4)are the follow-up of the patients over 2 years ago. In our study, patients under 3 cm (small and medium) and 3 cm above (large and massive) as we group. Tears under 3 cm was named as group 1, 3 cm above the tears were classified as group 2. 33 patients in group 1, 31 patients group 2 were classified. The patients preoperatively, postoperatively at 6 months, 12 months and finally at 24 months VAS scores, joint ROMs, Constant and UCLA scores were evaluated. At the end of 2 years, patients MRI taken as a result of rupture rates and functional outcomes were compared. Results: Between the groups; age, sex, side, AC joint pathology and the dominant limb with respect was found that no statistically significant difference (p>0.05). According to MRI results rupture rate of 33.3% in group 1, group 2 was found to be 19.4%. The comparison between groups; Constant score at all measurement values were found to be statistically significant difference (p<0.05). 3 cm below the rotator cuff tear time of four measurements was found to be higher than the constant score. The comparison between groups; VAS and UCLA scores in all measured time was found that no statistically significant difference (p>0.05). Conclusions: Double row repair technique is a safe surgical technique that can be applied regardless of the size of the tear. 3 cm above the rotator cuff tear in functional outcomes are worse, rupture rate is higher.

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Operative Management of Acute Triceps Tendon Ruptures: Review of 184 Cases

The American Journal of Sports Medicine ◽

10.1177/0363546518757426 ◽

2018 ◽

Vol 46 (6) ◽

pp. 1451-1458 ◽

Cited By ~ 10

Author(s):

Raffy Mirzayan ◽

Daniel C. Acevedo ◽

Jeffrey F. Sodl ◽

Edward H. Yian ◽

Ronald A. Navarro ◽

...

Keyword(s):

Medical Care ◽

Primary Repair ◽

Reoperation Rate ◽

Weight Lifting ◽

Suture Repair ◽

Level Of Evidence ◽

Significant Difference ◽

Tendon Ruptures ◽

The Mean ◽

Triceps Tendon

Background: Distal triceps tendon ruptures are rare. The authors present a series of 184 surgically treated, acute, traumatic triceps tendon avulsions and compare the complications between those treated with anchors (A) versus transosseous (TO) suture repair. Hypothesis: No difference exists in the retear rate between TO and A repairs. Study Designed: Cohort study; Level of evidence, 3. Methods: All patients who underwent an open primary repair of a traumatic triceps tendon avulsion within 90 days of injury, between 2007 and 2015, were retrospectively reviewed. Surgeries were performed within a multisurgeon (75 surgeons), multicenter (14 centers), community-based integrated health care system. Patient demographic information, type of repair, complications, and time from surgery to release from medical care were recorded. Results: 184 triceps tears in 181 patients met the inclusion criteria. The mean age was 49 years (range, 15-83 years). There were 169 males. The most common mechanisms of injury were fall (56.5%) and weight lifting (19%). Mean time from injury to surgery was 19 days (range, 1-90 days); in 74.5% of cases, surgery was performed in 3 weeks or less. There were 105 TO and 73 A repairs. No significant difference was found between the two groups in the mean age ( P = .18), sex ( P = .51), completeness of tears ( P = .74), tourniquet time ( P = .455), and prevalence of smokers ( P = .64). Significant differences were noted between TO and A repairs in terms of reruptures (6.7% vs 0%, respectively; P = .0244), overall reoperation rate (9.5% vs 1.4%; P = .026), and release from medical care (4.3 vs 3.4 months; P = .0014), but no difference was seen in infection rate (3.8% vs 0%; P = .092). No difference was noted in release from medical care in patients who underwent surgery 3 weeks or less after injury compared with those undergoing surgery more than 3 weeks after injury (3.90 vs 4.09 months, respectively; P = .911). Conclusion: Primary repair of triceps ruptures with TO fixation has a significantly higher rerupture rate, higher reoperation rate, and longer release from medical care than does repair with A fixation. Implementation of suture anchors in triceps repairs offers a lower complication rate and earlier release from medical care.

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Interference Screw Versus Suture Anchors for Femoral Fixation in Medial Patellofemoral Ligament Reconstruction: A Biomechanical Study

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967121989282 ◽

2021 ◽

Vol 9 (3) ◽

pp. 232596712198928

Author(s):

Heath P. Gould ◽

Nicholas R. Delaney ◽

Brent G. Parks ◽

Roshan T. Melvani ◽

Richard Y. Hinton

Keyword(s):

Medial Patellofemoral Ligament ◽

Interference Screw ◽

Biomechanical Study ◽

Graft Fixation ◽

Mpfl Reconstruction ◽

Suture Anchors ◽

Femoral Fixation ◽

Significant Difference ◽

Load To Failure ◽

The Mean

Background: Femoral-sided graft fixation in medial patellofemoral ligament (MPFL) reconstruction is commonly performed using an interference screw (IS). However, the IS method is associated with several clinical disadvantages that may be ameliorated by the use of suture anchors (SAs) for femoral fixation. Purpose: To compare the load to failure and stiffness of SAs versus an IS for the femoral fixation of a semitendinosus autograft in MPFL reconstruction. Study Design: Controlled laboratory study. Methods: Based on a priori power analysis, a total of 6 matched pairs of cadaveric knees were included. Specimens in each pair were randomly assigned to receive either SA or IS fixation. After an appropriate reconstruction procedure, the looped end of the MPFL graft was pulled laterally at a rate of 6 mm/s until construct failure. The best-fit slope of the load-displacement curve was then used to calculate the stiffness (N/mm) in a post hoc fashion. A paired t test was used to compare the mean load to failure and the mean stiffness between groups. Results: No significant difference in load to failure was observed between the IS and the SA fixation groups (294.0 ± 61.1 vs 250.0 ± 55.9; P = .352), although the mean stiffness was significantly higher in IS specimens (34.5 ± 9.6 vs 14.7 ± 1.2; P = .004). All IS reconstructions failed by graft pullout from the femoral tunnel, whereas 5 of the 6 SA reconstructions failed by anchor pullout. Conclusion: In this biomechanical study using a cadaveric model of MPFL reconstruction, SA femoral fixation was not significantly different from IS fixation in terms of load to failure. The mean load-to-failure values for both reconstruction techniques were greater than the literature-reported values for the native MPFL. Clinical Relevance: These results suggest that SAs are a biomechanically viable alternative for femoral-sided graft fixation in MPFL reconstruction.

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Anatomic and Biomechanical Properties of Flat Medial Patellofemoral Ligament Reconstruction Using an Adductor Magnus Tendon Graft: A Human Cadaveric Study

The American Journal of Sports Medicine ◽

10.1177/03635465211009540 ◽

2021 ◽

pp. 036354652110095

Author(s):

Danko Dan Milinkovic ◽

Christian Fink ◽

Christoph Kittl ◽

Petri Silanpää ◽

Elmar Herbst ◽

...

Keyword(s):

Medial Patellofemoral Ligament ◽

Biomechanical Properties ◽

Mpfl Reconstruction ◽

Maximum Elongation ◽

Skeletally Immature ◽

Femoral Insertion ◽

Adductor Tubercle ◽

Adductor Magnus ◽

Load To Failure ◽

The Mean

Background: In contrast to the majority of existing techniques for reconstruction of the medial patellofemoral ligament (MPFL), the technique described in this article uses the adductor magnus muscle tendon to gain a flat, broad graft, leaving its distal femoral insertion intact, and does not require drilling within or near the femoral physis. It also allows for soft tissue patellar fixation and could facilitate anatomic MPFL reconstruction in skeletally immature patients. Purpose: To evaluate the anatomic and structural properties of the native MPFL and the adductor tendon (AT), followed by biomechanical evaluation of the proposed reconstruction. Study Design: Descriptive laboratory study. Methods: The morphological and topographical features of the AT and MPFL were evaluated in 12 fresh-frozen cadaveric knees. The distance between the distal insertion of the AT on the adductor tubercle and the adductor hiatus, as well as the desired length of the graft, was measured to evaluate this graft’s application potential. Load-to-failure tests were performed to determine the biomechanical properties of the proposed reconstruction construct. The construct was placed in a uniaxial testing machine and cyclically loaded 500 times between 5 and 50 N, followed by load to failure, to measure the maximum elongation, stiffness, and maximum load. Results: The mean ± SD length of the AT was 12.6 ± 1.5 cm, and the mean distance between the insertion on the adductor tubercle and adductor hiatus was 10.8 ± 1.3 cm, exceeding the mean desired length of the graft (7.5 ± 0.5 cm) by 3.3 ± 0.7 cm. The distal insertion of the AT was slightly proximal and posterior to the insertion of the MPFL. The maximum elongation after cyclical loading was 1.9 ± 0.4 mm. Ultimately, the mean stiffness and load to failure were 26.2 ± 7.6 N/mm and 169.7 ± 19.2 N, respectively. The AT graft failed at patellar fixation in 2 of the initially tested specimens and at the femoral insertion in the remaining 10. Conclusion: The described reconstruction using the AT has potential for MPFL reconstruction. The AT graft presents a graft of significant volume, beneficial anatomic topography, and adequate tensile properties in comparison with the native MPFL following the data from previously published studies. Clinical Relevance: Given its advantageous anatomic relationship as an application that avoids femoral drilling and osseous patellar fixation, the AT may be considered a graft for MPFL reconstruction in skeletally immature patients.

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