Repair of patellar tendon rupture using suture anchors

Acute isolated rupture of the patellar tendon traditionally has been repaired via transpatellar suture tunnels. This retrospective study evaluated the demographics and epidemiology of this injury as well as the effectiveness and complication rates of our suture anchor technique. Between 1993 and 2005, a total of 82 cases of patellar tendon disruption in 71 patients were repaired. Fourteen cases involved basic primary repair with suture anchors of an acute isolated rupture of the patellar tendon and had an average follow-up of 29 months (range: 3-112 months). There were 3 (21%) failures of repair. The remaining 11 patients had excellent range of motion and strength and returned to their preoperative level of function. These results are comparable with other reports in the literature. The suture anchor technique thus represents a viable option for repair of patellar tendon ruptures and should be investigated further with a randomized, controlled trial.     

Distal attachment of flexor tendon allograft: A biomechanical study of different reconstruction techniques in human cadaver hands

We compared the mechanical force of tendon‐to‐bone repair techniques for flexor tendon reconstruction. Thirty‐six flexor digitorum profundus (FDP) tendons were divided into three groups based upon the repair technique: (1) suture/button repair using FDP tendon (Pullout button group), (2) suture bony anchor using FDP tendon (Suture anchor group), and (3) suture/button repair using FDP tendon with its bony attachment preserved (Bony attachment group). The repair failure force and stiffness were measured. The mean load to failure and stiffness in the bony attachment group were significantly higher than that in the pullout button and suture anchor groups. No significant difference was found in failure force and stiffness between the pullout button and suture anchor groups. An intrasynovial flexor tendon graft with its bony attachment has significantly improved tensile properties at the distal repair site when compared with a typical tendon‐to‐bone attachment with a button or suture anchor. The improvement in the tensile properties at the repair site may facilitate postoperative rehabilitation and reduce the risk of graft rupture. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:1720–1724, 2013     

Repair of Quadriceps and Patellar Tendon Tears

Tears of the quadriceps or patellar tendon usually occur after a sudden eabccentric contraction and are diagnosed by a palpable gap at the injury site combined with an inability to perform a straight leg raise. Bilateral knee radiographs may demonstrate patella alta with patellar tendon tears and patella baja with quadriceps tendon tears compared with the uninjured knee. Ultrasound and magnetic resonance imaging can be helpful when there is uncertainty in the diagnosis. Surgical treatment is indicated for complete tears and some high-grade, partial tears. Nonabsorbable high-strength sutures or suture tape are placed in running locking fashion along the injured tendon and secured to the patella with bone tunnels (i.e., transosseous) or suture anchors. The transosseous technique requires exposure of the length of the patella to drill 3 bone tunnels to shuttle the sutures and tie over either pole of the patella. The suture anchor technique allows for a smaller incision and less soft-tissue dissection and may use a knotted or knotless technique. Biomechanical testing with load to failure is not statistically different between the transosseous and anchor techniques, although anchors have been shown to have less gap formation at the repair site. Repair augmentation with a graft may be beneficial in mid-substance injuries, chronic tears, and in cases of compromised tissue quality. Rehabilitation usually can be initiated immediately with protected weight-bearing in an orthosis, safe-zone knee passive range of motion, and avoidance of active extension. After a period of 6 weeks, rehabilitation can progress with full range of motion and a concentric strengthening program.     

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

BackgroundMultiple 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.MethodsA 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%).ResultsA 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.ConclusionsTransosseous 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 evidenceSystematic review and meta-analysis of biomechanical studies, Level V.     

Editorial Commentary: Causes of Failure After Arthroscopic Rotator Cuff Repair

Causes of failure after arthroscopic rotator cuff repair include patient factors, tear factors, and surgical factors. Failure may occur at the suture–tendon interface, the bone–tendon interface, or the bone–anchor interface. Low bone mineral density (BMD) in the greater tuberosity has been reported as a prognostic factor for recurrent tears following rotator cuff repair, and although most studies suggest the tendon-to-suture interface as the “weakest link,” patients with low BMD may have lower suture anchor pull-out strength. A potential alternative cause of failure is the suture cutting through the greater tuberosity bone in patients with low BMD. Knotless suture bridge constructs or single-row constructs may be more susceptible to a suture cutting through the bone. The knotted suture bridge technique, wherein the medial mattress sutures are tied, may to some extent “shield” against complete cut-through. When bone quality appears poor, a common response is to change the type of anchor, size of anchor, or the location of the anchor. Other factors, such as bone preparation, suture type, suture tensioning, and anchor type (e.g., internal vs external locking), may all potentially affect suture cutting through weak bone.     

Editorial Commentary: Biology and Biomechanics Must Be Carefully Balanced for a Durable Rotator Cuff Repair

Arthroscopic rotator cuff repair strategies have evolved over 3 decades, but suture anchor design, anchor configuration, and stitches have been largely driven by repair biomechanics. In recent years there has been a shift toward repair strategies that enhance the biology of tendon repair. Double-row and transosseous equivalent suture anchor repair constructs demonstrate excellent time zero mechanical properties, but the resulting increased repair tension and tendon compression may compromise tendon healing. Modern single-row repairs employing medialized triple-loaded suture anchors, simple stitches, and lateral marrow venting avoid some of the problems associated with double-row repairs and demonstrate excellent short-term healing and clinical results. The most robust repair fails if the tendon does not heal. Biology and biomechanics must be carefully balanced.     

Biomechanical Comparison of Tape Versus Suture in Simulated Achilles Tendon Midsubstance Rupture

As sutures have progressed in strength, increasing evidence supports the suture tendon interface as the site where most tendon repairs fail. We hypothesized that suture tape would have a higher load to failure versus polyblend suture due to its larger surface area. Eleven matched pairs of cadaveric Achilles tendons were sutured with 2 mm wide braided ultrahigh molecular weight polyethylene tape (Tape) or 2 mm wide braided ultrahigh molecular weight polyethylene suture (Suture) using a Krackow repair method. All Achilles repair constructs were cyclically loaded, after which they were loaded to failure. Change in suture footprint height, clinical and ultimate load to failure, and location of failure was recorded. Clinical loads to failure for Tape and Suture were 290.4 ± 74.8 and 231.7 ± 70.4 Newtons, respectively (p= .01). Ultimate loads to failure for Tape and Suture were 352.9 ± 108.1 and 289.8 ± 53.7 Newtons, respectively (p = .11). Cyclic testing resulted in significant changes in footprint height for both Tape and Suture, but the 2 sutures did not differ in terms of the magnitude of change in footprint height (p = .52). The suture tendon interface was the most common site of failure for both Tape and Suture. Our results suggest that Tape may provide added repair strength in vivo for Achilles midsubstance rupture.     

Single-row Versus Double-row Repair of the Distal Achilles Tendon: A Biomechanical Comparison

Surgery for recalcitrant insertional Achilles tendinopathy often consists of partial or total release of the insertion site, debridement of the diseased portion of the tendon, calcaneal ostectomy, and reattachment of the Achilles to the calcaneus. Although single-row and double-row techniques exist for repair of the detached Achilles tendon, biomechanical data are lacking to support one technique over the other. Based on data extrapolated from the study of rotator cuff repairs, we hypothesized that a double-row construct would provide superior fixation strength over a single-row repair. Eighteen human cadaveric Achilles tendons (9 matched pairs) with attached calcanei were repaired with single-row or double-row techniques. Specimens were mounted in a servohydraulic materials testing machine, subjected to a preconditioning cycle, and loaded to failure. Failure was defined as suture breakage or pullout, midsubstance tendon rupture, or anchor pullout. Among the failures were 12 suture failures, 5 proximal-row anchor failures, and 1 distal-row anchor failure. No midsubstance tendon ruptures or testing apparatus failures were observed. There were no statistically significant differences in the peak load to failure between the single-row and double-row repairs (p = .46). Similarly, no significant differences were observed with regards to mean energy expenditure to failure (p = .069). The present study demonstrated no biomechanical advantages of the double-row repair over a single-row repair. Despite the lack of a clear biomechanical advantage, there may exist clinical advantages of a double-row repair, such as reduction in knot prominence and restoration of the Achilles footprint.     

An in vitro study comparing the use of suture anchors and drill hole fixation for flexor digitorum longus transfer to the navicular

BACKGROUND: The surgical management of posterior tibial tendon dysfunction often includes transfer of the flexor digitorum longus (FDL) tendon through a tunnel in the navicular. Fixation often is obtained by sewing the tendon back onto itself. The purpose of this study was to compare this standard method of fixation with suture anchor fixation, a technique that may be associated with less surgical morbidity, because it requires the harvesting of less tendon length. METHODS: FDL tendon transfer to the navicular was done in 13 fresh-frozen cadaver specimens. In six feet comprising the standard group, the FDL tendon was transected distal to the master knot of Henry, placed through a drill hole into the navicular, and sutured back onto itself. In seven feet the FDL tendon was transected proximal to the master knot of Henry, placed into a drill hole into the navicular, and fixed with a suture anchor. Load was applied to the proximal FDL muscle and tendon using a materials testing system (MTS) machine and peak load to failure was measured. RESULTS: The mean load to failure was 142.48 N +/- 38.06 N for the standard group and 142.12 N +/- 59.26 N for the suture anchor group (p = 0.305 for the Student-t test and p = 0.945 for the Mann-Whitney test). CONCLUSION: Transfer of the FDL tendon to the navicular using suture anchor fixation requires less tendon length yet provides similar fixation strength as compared to sewing the tendon back onto itself. However, suture anchors are considerably more expensive than sutures. CLINICAL IMPLICATIONS: Suture anchors allow comparable fixation of FDL tendon transfer into a navicular without the need to disrupt the master knot of Henry. This technique may be associated with less morbidity including a shorter incision, decreased risk of medial plantar nerve injury, and decreased loss of lesser toe plantarflexion strength secondary to maintenance of the normal interconnections between the flexor hallucis longus (FHL) and FDL tendons.     

Editorial Commentary: Suture Type or Technique Has Little Influence on Outcome After Acute Lower-Extremity Tendon Rupture

Operative repair of Achilles tendon rupture significantly decreases the rerupture rate, regardless of type of surgical suture technique. Likewise, regarding repair of either the quadriceps or patellar tendon, surgical repair technique does not significantly influence the generally excellent outcomes achieved, whereas too-early mobilization should be avoided. In terms of the use of suture versus suture tape, load to failure is similar. Many factors impact tendon rupture repair success, including postoperative care, the quality of the tendon, underlying medical issues, and patient compliance, but suture type or technique has little influence on outcome after acute lower-extremity tendon rupture.     

Suture anchor repair of quadriceps tendon rupture after total knee arthroplasty

Disruption of the extensor mechanism after total knee arthroplasty (TKA) is a devastating complication, usually requiring surgical repair. Although suture anchor fixation is well described for repair of the ruptured native knee quadriceps tendon, no study has discussed the use of suture anchors in quadriceps repair after TKA. We present an illustrative case of successful suture anchor fixation of the quadriceps mechanism after TKA. The procedure has been performed in a total of 3 patients. A surgical technique and brief review of the literature follows. Suture anchor fixation of the quadriceps tendon is a viable option in the setting of rupture after TKA.     

Biomechanical Comparison of Knotless Suture Anchor Versus Percutaneous End-to-End Technique for Mid-Substance Achilles Tendon Rupture Repair

Percutaneous Achilles tendon repairs can be performed with 2 distal fixation techniques: knotless suture anchor repair (KL) or percutaneous end-to-end repair (ETE). There is a paucity of literature comparing the biomechanical strength of these 2 distal fixation techniques. The aim of this study was to compare the strength of KL and ETE repairs using flat-braided suture for mid-substance Achilles tendon rupture during simulated progressive rehabilitation. Nine matched pairs of fresh-frozen below-knee cadaveric extremities were randomly assigned into these 2 repair groups. Each specimen was tested in 2 parts sequentially; Part I simulating passive ankle range of motion (cyclic: 20N-100N), and Part II simulating ambulation in a walking boot (cyclic: 20N-190N). The number of cycles, gap displacement, and the mode of failure were recorded for each repair. Achilles tendon repairs using the percutaneous methods of ETE and KL techniques showed no significant difference in the number of cycles to clinical failure, mean gap displacement, or overall failure rate. During Part I, the survival rate in terms of clinical failure for KL and ETE groups was 8 of 9 repairs and 7 of 9 repairs, respectively. During Part II, all repairs experienced clinical failure in both groups. Five repairs in the KL group experienced suture anchor pull out from the calcaneus, and 3 repairs failed at suture-tendon interface. Four repairs in the ETE group failed due to knot slippage and 5 repairs failed at suture-tendon interface. Both techniques are viable options in treating acute mid-substance Achilles tendon ruptures.     

Editorial Commentary: Repair of Posterior-Medial Meniscal Root Tears: One More Potential Tool in Your Box

No topic in meniscal surgery has generated as much interest over the past decade as meniscal root tears. These rather simple tears, if left untreated, act biomechanically equivalently to a complete meniscectomy. As a result, many investigators have championed the treatment of this injury through the innovation of various surgical techniques designed to restore the biomechanical function of the meniscus to prevent the long-term clinical effects of a complete meniscectomy. Most procedures to repair the posterior meniscal root to its tibial attachment can be broadly grouped into using either a suture anchor or a transtibial bone tunnel for tibial fixation. There are obvious pros and cons to both methods, and most surgeons become comfortable with one “go-to” technique depending on their level of experience with meniscal root repair and their comfort level with various arthroscopic techniques. Most surgeons prefer the transtibial technique in which the sutured meniscus is anchored to its anatomic tibial attachment via a tunnel through which the sutures pass before being secured with either a suture anchor or screw post to the anterior tibial cortex. This technique has considerable biomechanical and clinical evidence to support its use. Unfortunately, there are drawbacks to the transtibial method that must be considered, such as the technical difficulties of accurately and safely drilling the tibial tunnel, the risk of suture failure or attenuation through the tunnel, and the challenge associated with placement of the tunnel in the setting of a concurrent anterior cruciate ligament reconstruction. Therefore, further advances in meniscal root repair are always welcomed by the arthroscopic community. However, as with any surgical innovation, 3 factors must be considered before a new repair procedure can be widely recommended: (1) it must be technically “doable” by most surgeons treating the clinical problem; (2) it must have biomechanical evidence to support its use; and (3) it must result in clinical outcomes that are at least as good as, and preferably better than, current techniques.     

Spontaneous bilateral patellar tendon rupture: a case report and review of the literature

Bilateral rupture of the patellar tendon is a very rare injury. It occurs in association with chronic systemic diseases or corticosteroid medications. We report a case of a 13-year-old child with Ehlers-Danlos syndrome presenting a bilateral patellar tendon disruption of proximal insertion that occurred with a trivial trauma. Surgical management consisting in tendon repair with a suture anchor technique protected temporarily with a cerclage wiring gives a good outcome.     

Knotless suture anchor: arthroscopic bankart repair without tying knots

Arthroscopic Bankart repair done using suture anchors most closely mimics open repair techniques. The challenge with the arthroscopic technique is tying consistent, good quality arthroscopic knots. A unique knotless suture anchor and method of use for arthroscopic Bankart repair is described. The Knotless Suture Anchor has a short loop of suture secured to the tail end of the anchor. A channel is located at the tip of the anchor that functions to capture the loop of suture after it has been passed through the ligament. The ligament is tensioned as the anchor is inserted into bone to the appropriate depth. Mechanical testing showed increased suture strength in the Knotless Suture Anchor compared with standard suture anchors. This is attributable to the doubled suture configuration that is created with the Knotless Suture Anchor loop. To the author's knowledge, the current study describes the first knotless suture anchor. A secure, low-profile repair can be created without arthroscopic knot tying.     

Simultaneous bilateral quadriceps tendon rupture in a patient with chronic renal failure

Bilateral quadriceps tendon rupture is an unusual injury, but may be encountered in patients with various chronic diseases after minor trauma. This article presents a case of bilateral quadriceps tendon rupture of a 38-year-old woman with chronic renal failure. Surgical repair was performed using a bone tunnel technique with a nonabsorbable suture and a suture anchor. Postoperative magnetic resonance imaging confirmed complete healing of the repair site, and clinically active extension with 120 degrees of range of motion was achieved.     

Editorial Commentary: From Lateral Release and Medial Plication to Complex Medial Patellofemoral Ligament Reconstruction Techniques: Medial Quadriceps Tendon Femoral Ligament Reconstruction Is the Most Anatomic Repair

Patella instability and dislocation are common in younger patients, and 1 in 5 patients are at risk of recurrent dislocations. Conservative treatment should be considered for first dislocations unless other concomitant injuries are present. Historically, lateral patella release and medial plication techniques were used for repair but have been superseded by medial patellofemoral ligament reconstruction. Overconstraint is a potential problem and often related to nonanatomic femoral tunnel position and graft tension, which could result in increased patellar contact pressures and graft failure. The medial quadriceps tendon–femoral ligament reconstruction technique (MQTFL) avoids patellar tunnels without the risk of patella fracture. When comparing medial patellofemoral ligament, MQTFL, and the combination of both techniques in a cadaver model, MQTFL resulted in less constraint with no differences for patellar contact pressures. Medial quadriceps tendon femoral ligament reconstruction is the most anatomic repair.     

Quadrizeps- und Patellasehnenrupturen

Ruptures of the quadriceps or patellar tendon are uncommon but extremely relevant injuries. Early diagnosis and surgical treatment with a stable suture construction are mandatory for a good postoperative clinical outcome. The standard methods of repair for quadriceps and patellar tendon injuries include the placement of suture loops through transpatellar tunnels. Reinforcement with either a wire cerclage or a PDS cord is used in patellar tendon repair. The PDS cord can also be applied as augmentation in quadriceps tendon repair. In secondary patellar tendon repair an autologous semitendinosus graft can be used. For chronic quadriceps tendon defects a V-shaped tendon flap with a distal footing is recommended. The different methods of repair should lead to early functional postoperative treatment. The clinical outcome after surgical treatment of patellar and quadriceps tendon ruptures is mainly good.     

Evaluation of a New Knotless Suture Anchor Repair in Acute Achilles Tendon Ruptures: A Biomechanical Comparison of Three Techniques

Acute ruptures of the Achilles tendon are a common injury, and debate has continued in published studies on how best to treat these injuries. Specifically, controversy exists regarding the surgical approaches for Achilles tendon repair when one considers percutaneous versus open repair. The present study investigated the biomechanical strength of 3 different techniques for Achilles tendon repair in a cadaveric model. A total of 36 specimens were divided into 3 groups, each of which received a different construct. The first group received a traditional Krackow suture repair, the second group was repaired using a jig-assisted percutaneous suture, and the third group received a repair using a jig-assisted percutaneous repair modified with suture anchors placed into the calcaneus. The specimens were tested with cyclical loading and to ultimate failure. Cyclical loading showed a trend toward a stronger repair with the use of suture anchors after 10 cycles (p = .295), 500 cycles (p = .120), and 1000 cycles (p = .040). The ultimate load to failure was greatest in the group repaired with the modified knotless technique using the suture anchors (p = .098). The results of the present study show a clear trend toward a stronger construct in Achilles repair using a knotless suture anchor technique, which might translate to a faster return to activity and be more resistant to an early and aggressive rehabilitation protocol. Further clinical studies are warranted to evaluate this technique in a patient population.     

A Knotless Suture Anchor: Technique for use in arthroscopic Bankart repair

Arthroscopic Bankart repair performed using suture anchors most closely mimics open repair techniques. One of the challenges with the arthroscopic technique is tying consistent, good-quality arthroscopic knots. The unique Knotless Suture Anchor (Mitek Products, Westwood, MA) and method of use for arthroscopic Bankart repair is described. The Knotless Suture Anchor has a short loop of suture secured to the tail end of the anchor. A channel is located at the tip of the anchor that functions to capture the loop of suture after it has been passed through the ligament. The ligament is tensioned as the anchor is inserted into bone to the appropriate depth. The doubled suture configuration that is created with the loop increases the suture strength in the Knotless Suture Anchor compared with standard suture anchors with the same size suture. To my knowledge, this article describes the first knotless suture anchor. A secure, low-profile repair can be created without arthroscopic knot tying.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 17, No 2 (February), 2001: pp 213–218