Patellar Tendon Repair Augmentation With a Knotless Suture Anchor Internal Brace: A Biomechanical Cadaveric Study

Acute Patellar Tendon Ruptures: An Update on Management

Patellar tendon ruptures can be debilitating injuries. When incomplete, partial tears can be managed nonsurgically with immobilization and progressive rehabilitation. Although complete ruptures remain a relatively uncommon injury, they portend a high level of morbidity. Ruptures typically result from an acute mechanical overload to the extensor mechanism, such as with forced quadriceps contraction and knee flexion. However, chronically degenerated tendons are also predisposed to failure from low-energy injuries. Diagnosis can often be made clinically with recognition of a palpable defect to the tendon, localized patellar tendon tenderness, and inability to actively extend the knee. Diagnosis and surgical planning can be established with radiograph, ultrasonography, or magnetic resonance imaging. Surgical repair is the mainstay of treatment, and there have been many recent advances in repair technique, optimal reconstruction strategies, and supplemental fixation. Time to surgery for complete tears remains the most important prognosticator for success. Direct primary repair can be completed with transosseous tunnels, suture anchor repair, or end-to-end repair. Tendon reconstruction can be achieved with or without mechanical or biologic augments. Rehabilitation programs vary in specifics, but return to sport can be expected by 6 months postoperatively.

Biomechanical Comparison of Four- versus Six-Strand Transosseous Suture Repair for Patellar Tendon Rupture

BACKGROUND

 Surgical repair is indicated for patellar tendon ruptures that result in loss of knee extensor mechanism function. However, biomechanical studies report conflicting results when comparing transosseous suture versus suture anchor repair techniques. This discrepancy may be due to inconsistencies in experimental design as these studies use various numbers of suture strands. Therefore, the main objective of this study is to compare the ultimate load of four- versus six-strand transosseous suture repair. Secondary objectives are to compare gap formation after cyclical loading and mode of failure.

METHODS

 Six pairs of fresh-frozen cadaveric specimen were randomly allocated to either four- or six-strand transosseous suture repair. Specimen underwent preconditioning cyclical loading and then load to failure.

RESULTS

 The six-strand repair had a significantly higher maximum load to failure compared with the four-strand repair (mean difference = 319.3 N [57.9%], p = 0.03). There was no significant difference in gap length after cyclical loading or at max load. There were no significant differences in mode of failure.

CONCLUSION

 Utilizing a six-stand transosseous patella tendon repair construct with one additional suture increases overall construct strength by over 50% compared with a four-strand construct.

Suture Anchor Fixation Has Less Gap Formation and No Difference in Complications or Revisions for Patellar Tendon Repair: A Systematic Review

PURPOSE

To evaluate the literature on suture anchor (SA) usage for patellar tendon repair, summarize the overall biomechanical and clinical outcomes, and assess whether the cumulative research supports the adoption of this technique compared with transosseous (TO) repair.

METHODS

A systematic literature review using the Preferred Reporting Items for Systematic and Meta-Analyses guidelines was performed. Multiple electronic databases were searched to identify studies focusing on surgical outcomes of patellar tendon repair with suture anchor usage. Cadaver and animal biomechanical studies, technical studies, and clinical studies were included.

RESULTS

A total of 29 studies met the inclusion criteria: 6 cadaver, 3 animal, 9 technical, and 11 clinical reports. Four of the 6 cadaver studies and 1 of the 2 animal studies found significantly less gap formation from SA than from TO repair. Average gap formation in human studies ranged from 0.9 to 4.1 mm in the SA group compared with 2.9 to 10.3 mm in TO groups. Load to failure was significantly stronger in 1 of 5 cadaver studies and 2 of 3 animal studies, with human studies SA load to failure ranging from 258 to 868 N and TO load to failure ranging from 287 to 763 N. There were 11 clinical studies that included 133 knees repaired using SA. Nine studies showed no difference between complication rate or risk for reoperation, where one study reported a significantly lower re-rupture rate after SA repair compared with TO repair.

CONCLUSIONS

SA repair is a viable option for patellar tendon repair and could have several advantages over TO repair. Multiple studies indicate that SA repair has less gap formation during biomechanical testing compared with TO repair in human cadaver and animal models. No differences in complications or revisions were found in the majority of clinical studies.

CLINICAL RELEVANCE

Both animal and human models suggest SA fixation has potential biomechanical benefits when compared with TO tunnels for patellar tendon repair, whereas clinical studies show no difference in complications and revisions postoperatively.

Outcomes of multiligament knee injury treated with versus without internal brace suture augmentation

PURPOSE

To compare the postoperative outcomes between Internal Brace (IB) and non-IB patients who underwent surgical management of multiple-ligament knee injuries (MLKI).

METHODS

Patients who underwent surgical management of MLKI at two institutions between 2010 and 2020 were identified and offered participation in the study via the collection of postoperative functional outcomes for MLKI; Lysholm Knee score, Multiligament Quality of Life (ML-QOL), Patient-Reported Outcomes Measurement Information System (PROMIS) computer adaptive testing (CAT), Pain Interference (PI), Physical Function (PF), and Mobility instruments (MI). The postoperative outcomes and reoperation rates were compared between the IB group and non-IB group.

RESULTS

One hundred and twenty-six patients were analyzed; 89 were included in the IB group (31.5% female; age 35.6 ± 1.4 years), and 37 were included in the non-IB group (25.7% female; age 38.8 ± 2.4 years). Mean follow-up time of the entire cohort was 37.9 ± 4.7 months [IB: 21.8 + 1.63; non-IB: 76.4 ± 6.2, p < 0.001). The IB group achieved similar PROMIS CAT [PROMIS Pain (51.8 + 1.1 vs. 52.1 + 1.6, p = 0.8736), Physical Function (46.6 + 1.2 vs. 46.4 + 1.8, p = 0.9168), Mobility (46.0 + 1.0 vs. 43.7 + 1.6, p = 0.2185)], ML-QOL [ML-QOL Physical Impairment (36.6 + 2.5 vs. 43.5 ± 4.2, p = 0.1485), Emotional Impairment (42.5 + 2.9 vs. 48.6 ± 4.6, p = 0.2695), Activity Limitation (34.5 + 2.8 vs. 36.2 ± 4.3, p = 0.7384), Societal Involvement (39.1 + 3.0 vs. 41.7 + 4.2, p = 0.6434)] and Lysholm knee score (64.9 + 2.5 vs. 60.4 + 4.0, p = 0.3397) postoperatively compared the non-IB group, but the differences were not significant.

CONCLUSION

In this cohort of patients with MLKI treated with versus without IB, outcomes and reoperation rates trended toward favoring IB, but the study was not sufficiently powered to reach statistical significance. Internal bracing could be useful in the management of MLKI. In the future, matched patient cohorts with more patients are warranted to further evaluate the clinical impact of the internal brace in MLKI.

Clinical and biomechanical outcomes following patellar tendon repair with suture tape augmentation

PURPOSE

Patellar tendon ruptures (PTR) occur predominantly in middle-aged patients following indirect trauma. The aim of this study was to quantify the short-term results using a suture tape augmentation technique for the repair of PTR.

METHODS

All consecutive patients with acute (< 6 weeks) PTR who underwent suture tape augmentation between 03/2014 and 11/2019 at a single institution with a minimum follow-up of 12 months were retrospectively evaluated. Outcome measures included Visual Analog Scale (VAS) for pain, Tegner Activity Scale (TAS) and return to sport rates, Lysholm score, International Knee Documentation Committee subjective knee form (IKDC) as well as Knee Injury and Osteoarthritis Outcome Score (KOOS). Additionally, a standardized clinical examination and an isometric strength evaluation of knee extension and flexion were performed. It was hypothesized that high return to sport rates and good functional outcome would be observed and that the majority of patients would not present with a severe (> 20%) knee extension strength deficit when compared to the contralateral side.

RESULTS

A total of 7 patients (mean age 37.0 ± SD 13.5 years; 6 male/1 female) were available for final assessment at a median follow-up of 17.0 (25-75% IQR 16.0-77.0) months. Three injuries occurred during ball sports, two injuries occurred during winter sports, and one injury each occurred during a motorcycling and skateboarding accident. The average time between trauma and surgery was 4.7 ± 2.6 days. At follow-up, patients reported little pain (VAS: 0 [0-0.4]). Return to sport was possible for all patients 8.9 ± 4.0 months postoperatively at a high level (TAS: 7.0 [6.0-7.0]). Five patients (71.4%) returned to the preinjury level of play, and 2 (28.6%) did not return to the preinjury level of play. Patient-reported outcome measures were moderate to good (Lysholm score: 80.4 ± 14.5; IKDC: 84.2 ± 10.6; KOOS subscales: pain 95.6 ± 6.0, symptoms 81.1 [64.9-89.1], activities of daily living 98.5 [94.1-100], sport and recreation function 82.9 ± 14.1 and knee-related quality of life 75.9 ± 16.3). All patients were very satisfied (57.1%) or satisfied (42.9%) with the postoperative result. No postoperative complications were reported. Strength measurements revealed a severe knee extension deficit in 3 patients (42.9%), but no significant deficit of isometric knee extension or flexion strength in comparison with the contralateral side was observed overall (p > 0.05).

CONCLUSION

Suture tape augmentation in acute PTR repair leads to good functional outcome without major complications. Although a severe knee extension strength deficit may occur in some patients postoperatively, an excellent return to sports rate and high patient satisfaction can be expected nonetheless.

LEVEL OF EVIDENCE

Retrospective cohort study; III.

Biomechanical evaluation of three adjunctive methods of orthopedic tension band-wire fixation to augment simulated patella tendon repairs in dogs

OBJECTIVE

To evaluate the effects of three adjunctive methods of tension band wire fixation (TBWF) on the biomechanical properties, gap formation, and failure mode in simulated canine patella tendon rupture (RPT).

STUDY DESIGN

Randomized, ex vivo.

SAMPLE POPULATION

Paired hindlimbs from 32 dog cadavers.

METHODS

Patellar tendons (PTs) and associated bone-muscle-tendon units were harvested. Each PT was transected then sutured using a core locking loop and simple continuous epitendinous pattern. Each hindlimb was randomly assigned to one of three groups (n = 18 hindlimbs/group) using 18 gauge 316 L wire, anchored to the tibial crest distally, to perform transpatellar, suprapatellar, or combined tension band-wire (TBW) augmentation. Ten hindlimbs were utilized as control specimens. Yield, peak, and failure loads, stiffness, loads to 1 and 3 mm gap formation, and failure mode were evaluated.

RESULTS

Combined transpatellar and suprapatellar TBW augmentation was superior to transpatellar or suprapatellar groups alone. Yield (p = .0008), peak (p = .004), and failure loads (p = .005) were greater for the combined group than for the transpatellar (p = .048) and suprapatellar groups (p = .01) respectively. There was no difference regarding the occurrence of 1 or 3 mm gap formation (1 mm, p = .05; 3 mm, p = .06); however, loads required to cause gap formation were greater in the combined group (p = .036). Mode of failure differed between techniques used for PT augmentation (p < .001).

CONCLUSION

Combined transpatellar and suprapatellar adjunctive TBW augmentation for simulated PT repairs was biomechanically superior to either transpatellar or suprapatellar TBWF alone.

CLINICAL SIGNIFICANCE

Combined suprapatellar and transpatellar TBWF may offer a viable surgical option for increased repair-site strength and greater loads to gap formation. Further studies investigating alternative techniques and materials for RPT repair augmentation are warranted.

Effect of Poly-L-Lactic Acid Mesh Augmentation on Cyclic Gap Formation in Transosseous Patellar Tendon Repair: A Biomechanical Study

No previous study has investigated poly-L-lactic acid (PLLA) surgical mesh augmentation in the repair of inferior pole patellar tendon rupture. We compared the biomechanical properties of transosseous patellar tendon repair with PLLA surgical mesh augmentation to transosseous repair without augmentation. Ten matched pairs of cadaveric knees were used. Specimens in each pair were randomized to undergo the transosseous technique alone or the transosseous technique augmented with a PLLA surgical mesh. An inferior pole patellar tendon rupture was simulated and the repair procedure was performed. Specimens were cyclically loaded for 500 cycles. Gap formation was measured using two sensors placed medial and lateral to the repair site. After cyclic loading, load to failure was determined by pulling the tendon at a constant rate until a sudden decrease in load occurred. The primary outcome measure was cyclic gap formation at the medial and lateral sensors. Compared with controls, specimens that underwent PLLA mesh-augmented repair had significantly lower medial gap formation at all testing intervals up to 500 cycles (p < 0.05) and significantly lower lateral gap formation at all testing intervals from 10 to 500 cycles (p < 0.05). Transosseous patellar tendon repair augmented with a PLLA woven mesh device provided significantly greater resistance to gap formation compared with transosseous repair alone. These results suggest that PLLA mesh augmentation of the transosseous technique is biomechanically effective for patellar tendon repair.

Treating Combined Anterior Cruciate Ligament and Medial Collateral Ligament Injuries Operatively in the Acute Setting Is Potentially Advantageous

Combined injury of the anterior cruciate ligament (ACL) and medial collateral ligament (MCL) remains among the most common knee injury patterns in orthopaedics. Optimal treatment of grade III MCL injuries is still debated, especially when combined with ACL injury. Most patients with these severe injuries are treated conservatively for at least 6 weeks to allow for MCL healing, followed by delayed ACL reconstruction. Although acute treatment of the MCL was common in the 1970s, postoperative stiffness was frequently reported. Moreover, studies of such treatment failed to show clinical benefits of surgical over conservative treatment, and the MCL exhibited intrinsic healing capacity, leading to the consensus that all MCL injuries are treated conservatively. The current delayed treatment algorithm for ACL-MCL injuries has several disadvantages. First, MCL healing may be incomplete, resulting in residual valgus laxity that places the ACL graft at greater risk of failure. Second, delayed treatment lengthens the overall rehabilitation period, thereby prolonging the presence of atrophy and delaying return to preinjury activity levels. Third, the initial healing period leaves the knee unstable for longer and risks further intra-articular damage. Acute simultaneous surgical treatment of both ligaments has the potential to avoid these shortcomings. This article will review the evolution of treatment of ACL-MCL injuries and explain how it shifted toward the current treatment algorithm. We will (1) discuss why the consensus shifted, (2) discuss the shortcomings of the current treatment plan, (3) discuss the potential advantages of acute simultaneous treatment, and (4) present an overview of the available literature.

Augmentation in the repair of traumatic patellar tendon ruptures. A novel mechanical and biological construct: Technical note

Patellar tendon ruptures are infrequent and potentially disabling injuries. These injuries are usually repaired with transosseous suture tunnels. However, this technique can produce a significant gap formation and prolonged postoperative immobilization. Although several techniques have been described to improve the integrity of the repair, the surgical technique of choice is a matter of debate especially when there is tissue loss due to high-energy trauma. This study aims to evaluate the clinical outcomes of patients with acute patellar tendon ruptures due to high-energy trauma treated with a novel construct configuration that includes a suture anchor and a figure-of-eight augmentation with hamstring autograft with medial and lateral reinforcement. To determine the clinical outcomes the International Knee Documentation Committee (IKDC) score was obtained pre-surgery and at 12 months of follow-up. A total of six patients were recruited, with a median age of 27.5 years, five of these were male. Three lesions were in the proximal pole of the tendon, two were mid-substance and one was in the junction with tibial tuberosity. The IKDC clinical score significantly increased from pre-surgery to the 12-month follow-up with a median difference of 32.8 (95% CI, 19.5-42.6, p = 0.0313). Likewise, the patients presented a post-surgery quadriceps strength level with a median of 5/5. All patients had full active knee extension with a median of 0-120°. There was no statistical difference in the range of motion comparing the surgical knee to the contralateral knee (p = 0.6883). No patient presented any type of reintervention or complication during the follow-up period. The configuration of the construct presented in the technique had not been reported before in the literature and combines the advantages of the use of suture anchors and biological augmentation with lateral and medial reinforcement. This technique may be useful in patients with traumatic injuries with and without loss of tissue. Although it is a small series with concomitant injuries, satisfactory clinical results were presented during follow-up.

Traumatic Midsubstance Patellar Tendon Ruptures: A Unique Surgical Repair Technique in the Setting of Poor Tissue Quality

In the setting of traumatic midsubstance patellar tendon ruptures in which the tissue is unable to be repaired end to end, surgical options are limited. We offer a technique using suture anchors for the native tendon reconstruction, allograft augmentation, and a bioinductive implant.

Hybrid Knot and Knotless Suture Anchor Repair for Patellar Tendon Rupture

Background:

Patellar tendon ruptures are the third-most common injury involving the knee extensor mechanism. They typically occur in men under 40 years old as a result of eccentric quadriceps contraction while the knee is flexed and the foot is planted.1 The optimal treatment is surgical repair within 2 weeks of injury to prevent scar formation, degeneration, and loss of tendon excursion.

Indications:

Operative management is generally indicated for patellar tendon ruptures. In this case, a physically active, healthy 24-year-old man presented with acute pain, extensor lag, and patella alta related to a basketball injury. He was diagnosed with acute patellar tendon rupture/extensor mechanism disruption and indicated for surgery.

Technique description:

We describe a technique for primary patellar tendon repair which uses both knot-based and knotless suture anchor fixation. Using a pulley effect, sutures in the inferior patellar anchors are used to reduce and repair the patellar tendon back to its bony origin. Patellar anchor-based tapes and a suprapatellar traction suture are affixed with knotless anchors to the proximal tibia to reinforce the repair. Anchor-based suture limbs are used to repair the medial and lateral retinacula.

Results:

The senior authors’ experience with this technique has been excellent restoration of extensor mechanism function, with rehabilitation permitting early range of motion and no major complications or failures. This patient returned to unassisted activities of daily living between 8 and 12 weeks and had returned to gym workouts and recreational sports at 12 months.

Discussion/conclusion:

Biomechanical studies have demonstrated that compared with transosseous repair, suture anchor repair decreases gap formation and improves ultimate load to failure. Advantages of suture anchor repair include smaller incision, less tissue dissection, shorter operative time, and improved repair biomechanics. Our technique follows a principle of tendon repair using a high number of suture and tape limbs to span the repair. In addition, this technique incorporates a “double row” of suture anchors and spans the primary repair with a suture and tape “internal brace.” The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Suture Tape Augmentation Increases the Time-Zero Stiffness and Strength of Anterior Cruciate Ligament Grafts: A Cadaveric Study

Purpose

Methods

Results

Conclusion

Clinical Relevance

Repair of Bilateral Quadriceps Tendon Rupture Using a Modified Knotless Suture Anchor and Internal Brace Technique: Surgical Technique and Case Report

BACKGROUND

Quadriceps tendon rupture (QTR) is a rare clinical condition often caused by indirect injury in healthy people. In addition, spontaneous and bilateral ruptures can occur in patients with predisposing factors, such as endocrine or rheumatic disease. Currently, several QTR repair techniques have been proposed; however, no consensus exists about the best repair technique.

CASE PRESENTATIONS

A 55-year-old man with renal failure secondary to glomerulonephritis suffered from spontaneous bilateral quadriceps tendon ruptures. Based on a knotless suture anchor and internal brace, a novel double-row suture-bridge configuration surgical approach was used to treat the patient. At 11-month follow-up, the patient maintained excellent function, with a Lysholm score of 91 for both knees.

CONCLUSIONS

This technique may be an effective method for repairing ruptured quadriceps tendons.

Smaller Gap Formation With Suture Anchor Fixation Than Traditional Transpatellar Sutures in Patella and Quadriceps Tendon Rupture: A Systematic Review

PURPOSE

The purpose of this study is to compare the biomechanical properties between traditional transosseous tunnel and suture anchor technique repair for extensor mechanism ruptures and assess for differences in the mechanism of failure of both techniques.

METHODS

A multi-database search (PubMed, EMBASE, and Medline) was performed according to PRISMA guidelines on November 14, 2021. All articles comparing biomechanical properties of transpatellar and suture anchor technique for extensor mechanism ruptures were included. Abstracts, reviews, case reports, studies without biomechanical analysis, conference proceedings, and non-English language studies were excluded. Outcomes pursued included gap formation, load to failure, and mechanism of failure. Relevant data from studies meeting inclusion criteria were extracted and analyzed. Study methodology was assessed using the Methodological Index for Non-Randomized Studies score.

RESULTS

A total of 212 knees were biomechanically assessed, including 98 patella and 114 quadricep tendon ruptures. Five patellar tendon studies were included, and all of them reported significantly smaller gap formation in suture anchor group. Gap formation for suture anchors ranged from .9 mm to 4.1 mm, while that of transpatellar group ranged from 2.9 mm to 10.3 mm. One study reported a significantly higher load to failure in the suture anchor group, while the remaining four studies reported no significant difference. Load to failure for suture anchor ranged from 259 N to 779 N, while that of the transpatellar group ranged from 287 N to 763 N. The most common mechanism of failure was anchor pullout in suture anchor and knot failure in the transpatellar group. Five quadriceps tendon studies were included, and three studies reported statistically significant smaller gap formation in the suture anchor group. Gap formation for suture anchor ranged from 1.5 mm to 5.0 mm, while that of transpatellar group ranged from 3.1 mm to 33.3 mm. Two studies reported a significantly higher load to failure in the suture anchor group, while one study reported a higher load to failure in the transpatellar repair group. Load to failure for suture anchor ranged from 286 N to 740 N, while that of transpatellar group ranged from 251 N to 691 N. The most common mechanism of failure was suture failure in the suture anchor and knot failure in the transpatellar group.

CONCLUSION

Suture anchor fixation displays a better biomechanical profile than traditional transpatellar techniques in terms of smaller gap formations in the repair of both patella and quadriceps tendon injuries. Anchor pullout in suture anchor fixation was present mainly with the use of titanium anchors.

CLINICAL RELEVANCE

These findings above may result in better retention of tendon approximation in patella and quadriceps tendon fixation postoperatively, which may result in earlier recovery. Further randomized controlled clinical trials to compare these techniques are required.

Transosseous tunnels versus suture anchors for the repair of acute quadriceps and patellar tendon ruptures: A systematic review and meta-analysis of biomechanical studies

BACKGROUND

Multiple techniques have been developed for the repair of acute quadriceps and patellar tendon ruptures with the goal of optimizing clinical outcomes while minimizing complications and costs. The purpose of this study was to evaluate the biomechanical properties of transosseous tunnels and suture anchors for the repair of quadriceps and patellar tendon ruptures.

METHODS

A systematic review of the PubMed and Embase databases was performed based on the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines using specific search terms and eligibility criteria. Meta-analysis was performed by fixed-effects models for studies of low heterogeneity (I² <25%) and random-effects models for studies of moderate to high heterogeneity (I² ≥25%).

RESULTS

A total of 392 studies were identified from the initial literature search with 7 studies meeting the eligibility criteria for quadriceps tendon repair and 8 studies meeting the eligibility criteria for patellar tendon repair. Based on the random-effects model for total gap formation and load to failure for quadriceps tendon repair, the mean difference was 8.88 mm (95% CI, -8.31 mm to 26.06 mm; p = 0.31) in favor of a larger gap with transosseous tunnels and -117.25N (95%CI, -242.73N to 8.23N; p = 0.07) in favor of a larger load to failure with suture anchors. A similar analysis for patellar tendon repair demonstrated a mean difference of 2.86 mm (95% CI, 1.08 mm to 4.64 mm; p = 0.002) in favor of a larger gap with transosseous tunnels and -56.34N (95% CI, -226.75 to 114.07N; p = 0.52) in favor of a larger load to failure with suture anchor repair.

CONCLUSIONS

Transosseous tunnels are biomechanically similar to suture anchors for quadriceps tendon repair. Patellar tendon repair may benefit from reduced gap formation after cycling with suture anchor repair, but the load to failure for both techniques is biomechanically similar. Additional studies are necessary to evaluate these and alternative repair techniques.

LEVEL OF EVIDENCE

Systematic review and meta-analysis of biomechanical studies, Level V.

Patellar Tendon Repair With Suture Tape Augmentation for Proximal Patellar Tendon Rupture

Patellar tendon ruptures are severe but uncommon injuries that require surgical treatment. Primary repair for acute patellar tendon ruptures using augmentation techniques has shown good results in terms of biomechanical and clinical outcomes. This Technical Note details patellar tendon repair with suture tape augmentation for proximal patellar tendon rupture. Because this surgical technique does not require harvesting of the hamstring tendon and hardware removal, it is minimally invasive. In addition, it is simple and quick to perform.

Traumatic Rupture of the Patellar Tendon From the Tibial Tuberosity in an Adult: A Case Report

Patellar tendon ruptures from the tibial tuberosity are very uncommon. Various surgical techniques are described for patellar tendon ruptures from the tibial tuberosity. A 58-year-old male without any predisposing factors had pain and swelling in the right knee due to a road traffic accident. Tense swelling and ecchymosis were present around the right knee with a palpable defect over the patellar tendon and an inability to extend the right knee. An MRI report revealed avulsion of the distal patellar tendon from the tibial tubercle insertion and medial meniscus tear. Primary repair was done with a double-loaded suture anchor and augmentation was done by using a Gracilis tendon. After the months, the knee range of motion (ROM) of the patient reached up to 90 degrees, and there was no extension lag on straight leg raise. Hamstring augmentation with a primary repair is the safest and a good surgical option in elderly patients with patellar tendon ruptures from the tibial tuberosity.

A Strategy for Repair, Augmentation, and Reconstruction of Knee Extensor Mechanism Disruption: A Retrospective Review

Background

The loss of extensor mechanism continuity that occurs with patellar and quadriceps tendon rupture has devastating consequences on patient function.

Purpose

To describe a treatment strategy for extensor mechanism disruption and evaluate the outcomes of 3 techniques: primary repair, repair with semitendinosus tendon autograft augmentation, and reconstruction with Achilles tendon allograft.

Study Design

Case series; Level of evidence, 4.

Methods

The authors reviewed surgeries for extensor mechanism disruption performed by a single surgeon between 1999 and 2019. Patient characteristics, imaging studies, surgical techniques, and outcomes were recorded. Primary ruptures with robust tissue quality were repaired primarily, and first-time ruptures with significant tendinosis or moderate tissue loss were repaired using quadrupled semitendinosus tendon autograft augmentation. Patients with failed previous extensor mechanism repair or reconstruction and poor tissue quality underwent reconstruction with Achilles tendon allograft. The primary outcome was extensor mechanism integrity at a minimum 1-year follow-up, with extensor mechanism lag defined as >5° loss of terminal, active knee extension. Secondary outcomes included postoperative knee range of motion, International Knee Documentation Committee (IKDC) and Tegner activity scores, and the radiographic Caton-Deschamps Index.

Results

Included were 22 patellar tendon and 21 quadriceps tendon surgeries (patients: 82.5% male; mean age, 48.1 years; body mass index, 31). Seventeen (39.5%) cases underwent primary tendon repair, 13 (30.2%) had repair using semitendinosus tendon autograft augmentation, and 13 (30.2%) underwent reconstruction using an Achilles tendon allograft. Seventeen (39.5%) cases had at least 1 prior failed extensor mechanism surgery performed at an outside facility. At the last follow-up, 4 (9.3%) cases had an extensor mechanism lag, no cases required additional extensor mechanism surgery, and all cases were able to achieve >90° of knee flexion. Postoperative IKDC scores were significantly improved with all methods of extensor mechanism surgery, and postoperative Tegner activity scores were significantly improved in patients who underwent primary repair and Achilles tendon allograft reconstruction (P < .05 for all).

Conclusion

Primary repair alone, repair using quadrupled semitendinosus tendon autograft augmentation, and reconstruction using Achilles tendon allograft were all effective methods to restore extensor mechanism and knee function with the proper indications. Persistent knee extensor lag was more common in chronic extensor mechanism injuries after failed surgery, although patients still reported significantly improved postoperative functional outcomes.

Suture Tape Augmentation Has No Effect on Anterior Tibial Translation, Gap Formation, or Load to Failure of Anterior Cruciate Ligament Repair: A Biomechanical Pilot Study

Purpose

The purpose of our pilot study was to assess the effect of augmenting anterior cruciate ligament (ACL) repair with suture tape on biomechanical parameters including anterior tibial translation, gap formation, and load to failure.

Methods

Ten fresh-frozen nonpaired cadaveric knees were dissected, and baseline anterior-posterior stability of both ACL-intact and -deficient knees was obtained. The specimens were randomized to undergo ACL repair either with or without suture tape reinforcement, and anterior tibial translation, as well as gap formation, was measured after cyclic loading. Finally, all specimens were subjected to a single pullout force to determine maximum load to failure. We performed t test analysis to compare means between groups, and significance was defined as P < .05.

Results

On t test analysis, no statistically significant difference was found regarding anterior tibial translation between the ACL-intact group and either repair group or between the repair group without suture tape augmentation and the repair group with suture tape augmentation. No significant difference in gap formation was detected between the repair groups with and without suture tape augmentation at 100 cycles (1.25 mm vs 1.02 mm, P = .6), 250 cycles (2.87 mm vs 2.12 mm, P = .3), and 500 cycles (4.5 mm vs 4.55 mm, P = .5). The average load to failure of the repairs without suture tape augmentation was not significantly different from that of the repairs with suture tape augmentation (725.9 N vs 725.7 N, P = .99).

Conclusions

In this pilot study, we did not identify a difference between ACL repairs with and without suture tape augmentation regarding anterior tibial translation, gap formation, or maximum load to failure.

Clinical Relevance

Treatment of ACL tears with primary ACL repair is a highly debated topic, and studies such as this study to further our understanding of the biomechanical properties of augmented ACL repairs are important for surgeons when deciding the best treatments for their patients.

High-Strength Suture Tape Augmentation Improves Cyclic Gap Formation in Transosseous Patellar Tendon Repair: A Biomechanical Study

Purpose

To compare gap displacement at various intervals of cyclic testing and biomechanical load to failure of a Krackow patellar tendon repair augmented with high-strength suture tape versus the standard Krackow transosseous technique for inferior pole patellar tendon rupture.

Methods

Twelve matched pairs of cadaveric knees were used (8 males and 4 females; mean age 79.6 years, range 57 to 96). An inferior pole patellar tendon rupture was simulated after random assignment of specimens in each pair to the standard or augmented Krackow technique. Each specimen was then repetitively cycled from 90° to 5° for 1,000 cycles. A differential variable reluctance transducer was used to measure gap displacement. After cyclic loading, load to failure was determined by pulling the tendon at a rate of 15 mm/s until a sudden decrease in load occurred.

Results

Compared with the control repair, specimens with augmented repair demonstrated significantly less displacement at all testing intervals up to 1,000 cycles (P < .05). Two patellar tendons failed before the end of cyclic loading, and 4 specimens had inadequate tendon length for loading. Among the 18 remaining specimens, no significant difference in load to failure was observed between the experimental group (n = 11) and the control group (n = 7) (1,006.5 ± 332.1 versus 932.8 ± 229.1 N, respectively; P = .567).

Conclusions

Significantly greater gap displacement was observed in the standard Krackow repair group compared with the augmented Krackow group at all cyclic loading intervals. This suggests that the Krackow transosseous procedure augmented with high-strength suture tape is biomechanically viable for inferior pole patellar tendon repair.

Clinical Relevance

This biomechanical study supports the use of high-strength suture tape augmentation of Krackow transosseous repair for inferior pole patellar tendon rupture.

Internal Bracing Augmentation for Scapholunate Interosseous Ligament Repair: A Cadaveric Biomechanical Study

PURPOSE

Internal bracing (IB) is an augmentation method using high-strength nonabsorbable tape. This study compared scapholunate interosseous ligament (SLIL) repair alone, SLIL repair with IB augmentation (RIBA), and native intact SLIL (NIS) in a biomechanical cadaveric model.

METHODS

We used 21 specimens of fresh-frozen wrists in this study (7 matched pairs, SLIL repair-only and SLIL RIBA groups; and 7 independent fresh-frozen wrists, NIS group). In the SLIL RIBA group, augmentation using IB was performed after the repair. The specimens were preloaded and cyclically loaded in tension. Maximum extension and hysteresis were measured in all specimens. The specimens were subsequently tested for load to failure. Failure load (yield point load, mean ultimate load, and load at clinical failure) and linear stiffness were calculated.

RESULTS

In cyclic tensile testing, RIBA showed lower maximum extension and lower hysteresis than repair alone. In load to failure testing, the yield point load was statistically higher in the RIBA (59.3 N) group than in the repair-only (30.4 N) group but showed no significant difference compared with the NIS (90.7 N) groups. Moreover, the RIBA (98.5 N) group showed higher and lower mean ultimate loads than the repair-only (37.7 N) and NIS (211.8 N) groups, respectively. Load at clinical failure was higher with RIBA than with repair alone (3-mm extension: 70.0 vs 26.4 N; 4-mm extension: 84.1 vs 33.4 N). Repair alone and RIBA had comparable linear stiffness (38.2 vs 44.1 N/mm).

CONCLUSIONS

Although SLIL RIBA did not recreate biomechanical properties equivalent to those of NIS, it demonstrated a significantly higher strength than repair alone.

CLINICAL RELEVANCE

Repair with IB augmentation could serve as a novel surgical technique that enhances SLIL direct repair through biomechanical support.

[Patellar tendon ruptures : Internal bracing and augmentation technique]

OBJECTIVE

To report a surgical technique for the treatment of patellar tendon ruptures augmented with an internal brace suture tape.

INDICATIONS

Acute patellar tendon ruptures, fractures of the distal patellar pole, chronic insufficiency of the patellar tendon or revision surgery for failed repairs.

CONTRAINDICATIONS

Severe damage to the surrounding soft tissue. Local infection. Life-threatening conditions.

SURGICAL TECHNIQUE

Direct longitudinal anterior approach to the patellar tendon. Two parallel transosseous bone tunnels are drilled in the patella and tibial tuberosity with a 2.4 mm drill bit. Two separate FiberTapes® (Arthrex, Naples, FL; USA) are shuttled through the proximal and distal bone tunnels around the tendon in "X" and "O" type configuration. Patellar height is reestablished under fluoroscopic control and both FiberTapes are tied down. Both tendon ends are debrided and readapted with absorbable sutures.

POSTOPERATIVE MANAGEMENT

Passive motion exercise to 90° of flexion from day 1. Partial load to 20 kg of body weight with knee in locked full extension brace during first 2 weeks. Isometric exercises from week 3. Passive flexion to 110° from week 4 (adapted to pain). Free active range of motion and weight bearing from week 7.

RESULTS

In more than 10 years of clinical application, positive results were continuously found in acute as well as chronic patellar tendon ruptures. These results are consistent with those in the current literature.

Surgical Technique: Repair of Patella Tendon Rupture in a Previously Harvested Tendon for an Anterior Cruciate Ligament Reconstruction

Background:

A rare cause of patellar tendon (PT) ruptures is complications after bone-PT-bone (BPTB) graft harvest for anterior cruciate ligament (ACL) reconstruction. The atypical tear pattern in these patients can be technically challenging to address.

Description of Technique:

A Krackow suture fixation of the medial, tibial based PT was fixed with a knotless suture anchor to the patella. A Krackow suture fixation of the lateral, patella based PT was fixed with a knotless suture anchor to the tibia. Fiber Tape was used for an Internal Brace.

Patient and Methods:

We retrospectively reviewed a single patient with a proximal-medial and distal-lateral PT rupture following BPTB graft harvest for an ACL reconstruction. The described repair technique was used to repair the PT rupture. Follow-up was 6-months. Range of motion (ROM), functional outcome scores, and patient-reported outcomes were assessed and recorded.

Results:

Six-months postoperatively, the patient has regained full knee extension and flexion to 130 degrees. The patient has good quadriceps strength, and manual muscle testing shows no deficits in the operative leg. The patient is able to perform all of her activities of daily living and is discharged from physical therapy.

Conclusion:

We describe a novel technique that effectively repairs the atypical PT rupture pattern seen after ACL reconstruction using BPTB autograft. This technique allows for aggressive post-operative rehabilitation in ROM and strengthening.

Level of Evidence:

Level V.

Treatment of a Neglected Patellar Tendon Rupture with a Modified Surgical Technique: Ipsilateral Semitendinosus Autograft Reconstruction with Suture Tape Augmentation

Patellar tendon ruptures are rare, but debilitating injuries are typically seen in young active males in the third and fourth decades of life. They can occur as a single acute injury or from repetitive microtrauma weakening the tendon. Patients typically present complaining of knee pain, swelling, and an inability to perform a straight leg raise. Most conventionally, these injuries are classified as acute (less than two weeks) or chronic (greater than two weeks) based upon the timing of presentation. In patients with patellar tendon ruptures and inability to perform a straight leg raise, patellar tendon repair is most often recommended. A subset of patients with chronic patellar tendon ruptures, however, presents several months after their initial injuries. These neglected patella tendon ruptures present a particularly challenging clinical scenario in which primary repair is often difficult or not possible. This case report describes a modification to an existing surgical technique for reconstructing the patellar tendon using an ipsilateral semitendinosus tendon autograft with suture tape augmentation.