Early active motion and weightbearing after cross-stitch achilles tendon repair

Biomechanical Comparison of Nonlocked Minimally Invasive and Locked Open Achilles Tendon Simulated Rupture Repairs

BACKGROUND

Open repair of Achilles tendon ruptures is associated with a risk of infection and other wound complications. Although percutaneous repairs reduce these complications, they may increase the risk of nerve injury. This study was designed to determine whether a percutaneous nonlocking repair can approach the gapping resistance offered by a standard open repair under conditions approximating typical postoperative physiotherapy.

METHODS

Ten pairs of cadavers Achilles tendons were transected in situ 5 cm above the insertion. One tendon from each pair was repaired using an open 4-strand Krackow locking loop, and the contralateral tendon was repaired with the Achillon system using the same suture material. Displacement transducers were attached to the medial, lateral, anterior, and posterior aspects of the tendon, spanning the repair. Each tendon underwent 1000 tensile loading cycles to 86.5 N, simulating passive ankle range-of-motion physiotherapy. Gapping was documented on the 1st, 50th, 100th, 500th, and 1000th cycles. The ultimate tensile strength of each repaired tendon was then measured by distracting until gross failure occurred.

RESULTS

Gapping of the percutaneous repairs exceeded that of conventional open repairs on the first, 500th, and 1000th load cycles. All 10 conventionally repaired tendons withstood 1000 load cycles without gross failure, but 4 of 10 percutaneous minimally invasive repairs failed, one on the 9th load cycle and the others between the 100th and 500th cycles. On average, tendons repaired with the open technique withstood 66% greater tensile load in failure testing than those repaired with the percutaneous technique.

CONCLUSION

Open Krackow Achilles tendon repairs may better withstand more aggressive postoperative physiotherapy than nonlocked percutaneous repairs.

CLINICAL RELEVANCE

The study suggests that surgeons should consider locking suture approaches to avoid loss of repair integrity with early motion.

Calcaneotibial screws for immobilisation of the tarsocrural joint of dogs in extension: effect of the angle of screw placement on the force to failure in a canine cadaveric model

AIMS

To compare the force to failure under axial loading of a calcaneotibial screw placed approximately perpendicular to the tibia with that of a screw placed perpendicular to the calcaneus, when used to immobilise the tarsus in an ex vivo canine model.

METHODS

Twelve pairs of cadaveric hindlimbs from large breed dogs, without orthopaedic or soft tissue disease, were prepared by transecting the limb at the level of the stifle and stripping the limbs of all musculature from the stifle to mid-metatarsus, including removal of the common calcaneal tendon from all limbs. The limbs in each pair were randomly assigned to receive a calcaneotibial screw placed perpendicular to the long axis of either the calcaneus (C group) or the tibia (T group) with the tarsus in full extension. The distal limb was potted in resin and the proximal tibia was pinned to allow biomechanical testing in compressive loading. Testing was performed to apply an axial load using a material testing machine in a proximodistal direction through the tibia, advancing at a rate of 10 mm/second. The force to failure was recorded in kN and compared between groups.

RESULTS

The median force to failure of the C group was 0.86 (min 0.50; max 1.64) kN which was higher than the T group which had a median force to failure of 0.74 (min 0.26, max1.05) kN (p = 0.004). All modes of failure were by screw pull-out.

CONCLUSIONS

A calcaneotibial screw placed at an angle approximately perpendicular to the long axis of the calcaneus, has a higher force to failure under axial loading than a calcaneotibial screw that is placed at an angle approximately perpendicular to the tibia, in a canine cadaveric model.

CLINICAL RELEVANCE

A temporary calcaneotibial screw is a common method of immobilising the tarsus in extension to protect primary repair of a common calcaneal tendon injury. Placing a calcaneotibial screw perpendicular to the calcaneus may be a more reliable option for immobilisation of the tarsus to protect a common calcaneal tendon repair compared to screws placed perpendicular to the tibia. However extrapolation of these results into a clinical setting requires caution.

Resistance Exercises in Early Functional Rehabilitation for Achilles Tendon Ruptures Are Poorly Described: A Scoping Review

OBJECTIVES

To (1) describe which resistance exercises are used in the first 8 weeks of treatment for acute Achilles tendon rupture and (2) assess the completeness of reporting of the exercise descriptions.

DESIGN

Scoping review.

LITERATURE SEARCH

We searched the MEDLINE, Embase, CINAHL, Cochrane Library, and Physiotherapy Evidence Database (PEDro) databases.

STUDY SELECTION CRITERIA

Randomized controlled trials, cohort studies, and case series (10 or more participants) that reported using resistance exercise in the immobilization period in the first 8 weeks of treatment for acute Achilles tendon rupture were included.

DATA SYNTHESIS

Completeness of exercise description was assessed with the Consensus on Exercise Reporting Template (CERT) and the Toigo and Boutellier exercise descriptor framework.

RESULTS

Thirty-eight studies were included. Fifty-one resistance exercises were extracted and categorized as isometric exercises (n = 20), heel raises (n = 6), strengthening with external resistance (n = 13), or unspecified (n = 12). A median of 8 (interquartile range, 6-10) of a possible 19 CERT items was reported. The amount of items described of the 13 Toigo and and Boutellier exercise descriptors ranged from 0 to 11.

CONCLUSION

A variety of resistance exercises targeted at the ankle plantar flexors were used as part of early functional rehabilitation after Achilles tendon rupture. However, most studies provided inadequate description of resistance exercise interventions. J Orthop Sports Phys Ther 2020;50(12):681-691. Epub 23 Oct 2020. doi:10.2519/jospt.2020.9463.

Defining Components of Early Functional Rehabilitation for Acute Achilles Tendon Rupture: A Systematic Review

Background:

Early functional rehabilitation is frequently discussed in treating Achilles tendon rupture. A consistent definition of what constitutes early functional rehabilitation has not been established across the literature, despite studies supporting its efficacy. A standardized definition would be helpful to pool data across studies, allow for between-study comparisons, and ultimately work toward developing clinical guidelines.

Purpose:

To define early functional rehabilitation (including when it is initiated and what it entails) when used to treat Achilles tendon rupture and to identify outcome measures for evaluating the effect of treatment.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

Ovid MEDLINE, EMBASE, PEDro, CINAHL, and Cochrane databases were searched for relevant studies. Eligibility criteria for selecting studies consisted of randomized controlled trials, cohort studies, and case series (≥10 participants) including weightbearing or exercise-based interventions within 8 weeks after Achilles tendon rupture.

Results:

A total of 174 studies published between 1979 and 2018 were included. Studies were rated a median (interquartile range [IQR]) of 17 (15-20) on the Downs & Black checklist and included 9098 participants. Early functional rehabilitation incorporated weightbearing (95%), range of motion (73%), and isometric/strengthening exercises (50%). Weightbearing was initiated within the first week, whereas exercise (eg, ankle range of motion, strengthening, whole-body conditioning) was initiated in the second week. Initiation of exercises varied based on whether treatment was nonsurgical (mean, 3.0 weeks; IQR, 2.0-4.0 weeks) or simple (mean, 2.0 weeks; IQR, 0.0-2.3 weeks) or augmented surgical repair (mean, 0.5 weeks; IQR, 0.0-2.8 weeks) (P = .017). Functional outcomes including ankle range of motion (n = 84) and strength (n = 76) were reported in 130 studies. Other outcome domains included patient-reported outcomes (n = 89), survey-based functional outcomes (n = 50), and tendon properties (n = 53).

Conclusion:

Early functional rehabilitation includes weightbearing and a variety of exercise-based interventions initiated within the first 2 weeks after acute Achilles tendon rupture/repair. Because early functional rehabilitation has lacked a standardized definition, interventions and outcome measures are highly variable, and pooling data across studies should be done with attention paid to what was included in the intervention and how treatment was assessed.

Medial Gastrocnemius Myotendinous Junction Displacement and Plantar-Flexion Strength in Patients Treated With Immediate Rehabilitation After Achilles Tendon Repair

CONTEXT

Pathologic plantar flexion frequently occurs after operative repair of the Achilles tendon (AT) because of immobilization and non-weight bearing in the first weeks of traditional rehabilitation. Novel rehabilitation strategies that apply mobilization and weight bearing have been proposed, but their effects on medial gastrocnemius myotendinous junction displacement (MJD) and isometric plantar-flexion strength (PFS) are unknown.

OBJECTIVE

To compare the effects of 12 weeks of immediate versus traditional rehabilitation on MJD and PFS in patients with percutaneous AT repair and to compare AT rupture scores (ATRSs) during follow-up.

DESIGN

Controlled laboratory study.

SETTING

Human performance laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 26 amateur soccer players (age = 42.3 ± 9.7 years, body mass index = 29.5 ± 3.9 kg/m²) with percutaneous AT repair.

INTERVENTION(S)

Athletes were randomly divided into 2 groups: an immediate group, given physical therapy from day 1 to day 84, and a traditional group, given physical therapy from day 29 to day 84. We used repeated-measures analysis of variance to compare the data.

MAIN OUTCOME MEASURE(S)

We measured MJD and PFS at days 28 (fourth week), 56 (eighth week), and 84 (12th week) after AT repair.

RESULTS

After 12 weeks of rehabilitation, we observed a large clinically meaningful effect and statistical difference between groups. At day 28, the immediate group showed higher values for PFS (P = .002), MJD (P = .02), and ATRS (P = .002) than the traditional group. At day 56, the immediate group presented higher values for MJD (P = .02) and ATRS (P = .009). At day 84, the immediate group registered more MJD (P = .001).

CONCLUSIONS

Compared with traditional rehabilitation, 12 weeks of immediate rehabilitation after percutaneous AT repair resulted in better MJD, PFS, and ATRS after 4 weeks; better MJD and ATRS after 8 weeks; and better MJD after 12 weeks.

Reinforcement of the Flexor Tendon Repair Using Human Amniotic MembraneA Biomechanical Evaluation Using the Modified Kessler Method of Tendon Repair

BACKGROUND

Human amniotic membrane is used to prevent peritendinous adhesions after tendon injuries. This study compares the mechanical properties of modified Kessler repairs and modified Kessler repairs strengthened using multiple layers of human amniotic membrane.

METHODS

Twenty flexor digitorum profundus tendons of sheep forelimbs were sutured by the two-strand modified Kessler technique (group A) and by the two-strand modified Kessler repair reinforced with multiple layers of human amniotic membrane (group B). To assess the mechanical performance of the repairs, tendons were subjected to a linear noncyclic load-to-failure test using a material testing machine. Outcome measures included ultimate forces and the mode of failure.

RESULTS

The mean ± SD value of the failure strength was 34.6 ± 1.64 N for group A and 50.6 ± 5.60 N for group B. The reinforced repair provided a significantly higher ultimate load compared with the nonreinforced group (P < .001). All of the specimens failed due to suture breakage at the repair site.

CONCLUSIONS

The results of this study show that the modified Kessler repair can be reinforced effectively with human amniotic membrane.

The Internal Brace for Midsubstance Achilles Ruptures

The efficient and effective function of the Achilles tendon is essential for normal gait and sporting performance. The optimal technique for the operative repair of the Achilles midsubstance rupture remains controversial. Suboptimal outcomes are common even after successful Achilles repair. Factors contributing to poor outcomes include a tenuous soft tissue envelope (leading to wound complications, peritendinous adhesions, and poor tendon healing,) as well as failure to maintain appropriate musculotendinous length, even after successful repair.We present a new technique using the InternalBrace (IB) and a modification of the Percutaneous Achilles Repair System (PARS; Arthrex Inc, Naples, FL), the Achilles Mid-Substance Speed Bridge Repair. This IB approach is knotless, respects the soft tissue envelope, and allows the appropriate musculotendinous length to be set intraoperatively. The IB principle enables direct fixation to bone allowing early mobilization while minimizing the risk of knot slippage, accelerating recovery, and allowing for restoration of normal function.

LEVEL OF EVIDENCE

Level V, expert opinion.

Active Achilles tendon kinesitherapy accelerates Achilles tendon repair by promoting neurite regeneration

Active Achilles tendon kinesitherapy facilitates the functional recovery of a ruptured Achilles tendon. However, protein expression during the healing process remains a controversial issue. New Zealand rabbits, aged 14 weeks, underwent tenotomy followed immediately by Achilles tendon microsurgery to repair the Achilles tendon rupture. The tendon was then immobilized or subjected to postoperative early motion treatment (kinesitherapy). Mass spectrography results showed that after 14 days of motion treatment, 18 protein spots were differentially expressed, among which, 12 were up-regulated, consisting of gelsolin isoform b and neurite growth-related protein collapsing response mediator protein 2. Western blot analysis showed that gelsolin isoform b was up-regulated at days 7–21 of motion treatment. These findings suggest that active Achilles tendon kinesitherapy promotes the neurite regeneration of a ruptured Achilles tendon and gelsolin isoform b can be used as a biomarker for Achilles tendon healing after kinesitherapy.

Prevention of peritendinous adhesions using an electrospun DegraPol polymer tube: a histological, ultrasonographic, and biomechanical study in rabbits

Purpose. One of the great challenges in surgical tendon rupture repair is to minimize peritendinous adhesions. In order to reduce adhesion formation, a physical barrier was applied to a sutured rabbit Achilles tendon, with two different immobilization protocols used postoperatively. Methods. Thirty New Zealand white rabbits received a laceration on the Achilles tendon, sutured with a 4-strand Becker suture, and half of the rabbits got a DegraPol tube at the repair site. While fifteen rabbits had their treated hind leg in a 180° stretched position during 6 weeks (adhesion provoking immobilization), the other fifteen rabbits were recasted with a 150° position after 3 weeks (adhesion inhibiting immobilization). Adhesion extent was analysed macroscopically, via ultrasound and histology. Inflammation was determined histologically. Biomechanical properties were analysed. Results. Application of a DegraPol tube reduced adhesion formation by approximately 20%—independently of the immobilization protocol. Biomechanical properties of extracted specimen were not affected by the tube application. There was no serious inflammatory reaction towards the implant material. Conclusions. Implantation of a DegraPol tube tightly set around a sutured tendon acts as a beneficial physical barrier and prevents adhesion formation significantly—without affecting the tendon healing process.

Stem cell-bearing suture improves Achilles tendon healing in a rat model

BACKGROUND

Tendon healing is a slow and complicated process that results in inferior structural and functional properties when compared to healthy tendon tissue. It may be possible to improve outcomes of tendon healing with enhancement of biological aspects of the repair including tissue structure, organization, and composition. The purpose of this study was to determine whether use of a stem cell-bearing suture improves Achilles tendon healing in a rat model.

METHODS

The Achilles tendon was transected in 108 bilateral hind limbs from 54 rats. Each limb was randomized to repair with suture only (SO), suture plus injection (SI) of mesenchymal stem cells (MSCs) at the repair site, or suture loaded with MSCs (suture with stem cells, SCS). One half of the animals were randomly sacrificed at 14 and 28 days after surgery and the Achilles tendon was harvested. From each repair group at each time point, 12 limbs were randomized to biomechanical testing and 6 to histologic analysis. Tendons were loaded using a 223-N load cell at 0.17 mm/s. A blinded pathologist scored the histology sections.

RESULTS

Ultimate failure strength (N/mm(2)) was significantly higher in the SI and SCS groups versus the SO group. In the SI group, ultimate failure strength decreased significantly at 28 days versus 14 days. Histology score in the SCS group was significantly lower (better) than in both other groups (P ≤ .001). Histology findings at day 28 were significantly higher versus day 14 for all groups (P = .01).

CONCLUSIONS

Both the SI and the SCS groups had significantly higher ultimate failure strength versus the SO group, and strength was maintained at 28 days in the SCS group but not in the SI group. Histology in the SCS group was significantly better than in both other groups.

CLINICAL RELEVANCE

These findings in a rat model suggest that the use of stem cells enhances healing after Achilles repair and that embedding of stem cells directly into suture offers sustained early benefit to tendon healing.

Fixation of the Achilles tendon insertion using suture button technology

BACKGROUND

In the operative treatment of Achilles insertional tendinopathy, no guidelines exist concerning which form of fixation of the Achilles tendon insertion is superior.

HYPOTHESIS

Transcalcaneal drill pin passage does not place any major plantar structures at risk, and the addition of a Krackow stitch and suture button to the fixation technique provides a significant increase in ultimate load to failure in Achilles tendon insertional repairs.

STUDY DESIGN

Controlled laboratory study.

METHODS

The Achilles tendon insertions in 6 fresh-frozen cadaveric ankles were detached, and transcalcaneal drill pins were passed. Plantar dissection took place to evaluate the drill pin relationship to the plantar fascia, lateral plantar nerve and artery, flexor digitorum longus tendon, and master knot of Henry. The Achilles tendons were then repaired with a double-row suture anchor construct alone or with a suture button and Krackow stitch added to the double-row suture anchor construct. The repairs were then tested to maximum load to failure at 20 mm/min. The mode of failure was recorded, and the mean maximum load to failure was assessed using the Student t test for distributions with equal variance.

RESULTS

Transcalcaneal drill pin passage did not place any selected anatomic structures at risk. The mean maximum load to failure for the suture bridge group was 239.2 N; it was 391.4 N for the group with the suture button (P = .014). The lateral plantar artery was the structure placed at greatest risk from drill pin placement, with a mean distance of 22.7 mm (range, 16.5-29.2 mm) between the pin and artery.

CONCLUSION

In this laboratory study, transcalcaneal drill pin passage appeared to be anatomically safe, and the use of suture button technology with a Krackow stitch for Achilles tendon insertional repair significantly increased repair strength.

CLINICAL RELEVANCE

Achilles tendon insertional repair with suture button fixation and a Krackow stitch may facilitate the earlier institution of postoperative rehabilitation and improve clinical outcomes.

Kazakh therapy on differential protein expression of Achilles tendon healing in a 7-day postoperative rabbit model

OBJECTIVE

To compare the effect of cast immobilization with that of early Kiymil arkili emdew (Kazakh exercise therapy) on the post-operative healing of Achilles tendon rupture in rabbits, and to observe the influence of early Kiymil arkili emdew on the differentially expressed proteins in the healing tendon.

METHODS

Forty-five New Zealand white rabbits were randomly divided into three groups (Arm A: control group; Arm B: postoperative immobilization group; and Arm C: postoperative early Kiymil arkili emdew group). After tenotomy, the rabbits of the two experimental groups received microsurgery to repair the ruptured tendons, and then received either cast immobilization or early Kiymil arkili emdew treatment. Achilles tendon tissue samples were collected 7 days after the surgery, and two-dimensional gel electrophoresis and MALDI-TOF-MS technique were used to analyze differentially expressed proteins in the tendon tissue of the three Arms.

RESULTS

A total of 462.67 +/- 11.59, 532.33 +/- 27.79, and 515.33 +/- 6.56 protein spots were detected by the two-dimensional polyacrylamide gels in the Achilles tendon samples of the rabbits in Arms A, B, and C, respectively. Nineteen differentially expressed protein spots were randomly selected from Arm C. Among them, 7 were unique, and 15 had five times higher abundance than those in Arm B. These included annexin A2, gelsolin isoforms and alpha-1 Type III collagen. It was confirmed by western blot that gelsolin isoform b, annexin A2, etc. had specific and incremental expression in Arm C.

CONCLUSIONS

The self-protective instincts of humans were overlooked in the classical postoperative treatment for Achilles tendon rupture with cast immobilization. Kiymil arkili emdew induced the specific and incremental expression of proteins in the repaired Achilles tendon in the early healing stage in a rabbit model, compared with those treated with postoperative cast immobilization. These differentially expressed proteins may contribute to the healing of the Achilles tendon via a mechanobiological mechanism caused by the application of Kiymil arkili emdew.

Acute and chronic Achilles tendon ruptures in athletes

The Achilles tendon is the most injured tendon of athletes in the lower extremities and is the most common tendon to rupture spontaneously. Operative repair provides earlier return to sporting activities and lesser rate of rerupture. The general goal is to attempt anastomosis of the acute ruptured ends; however, delayed ruptures may require more extensive procedures. New surgical approaches, including percutaneous and mini-open techniques, are being introduced to potentially diminish perioperative complications. Advent of early protective range of motion and rehabilitation has shown a potential for earlier return to sporting activities for Achilles ruptures.

Augmented repair of acute tendo Achilles ruptures with gastrosoleus turn down flap

BACKGROUND

We present the results of primary repair of acute tendo Achilles (TA) rupture augmented with gastrosoleus turn down flap technique.

PATIENTS AND METHODS

78 consecutive patients with a complete acute rupture of the Achilles tendon operated between 1993 and 2004 were included in study. We performed a modification of the Lindholm technique in which the primary Kessler suture repair of the tendon was augmented by a turn-down ~3 cm × 10 cm gastrosoleus aponeurosis flap. In all cases, a short-leg circular walking cast was applied at 90° of the ankle dorsiflexion for 3 weeks and all the patients were encouraged to full weightbearing ambulation immediately. After removal of the cast, isometric and isokinetic ankle exercises were performed for 3 weeks. Modified Rupp Score was used to evaluate the subjective satisfaction.

RESULTS

All of patients returned to daily activity and 54 (69%) of them returned to previous sport activity. The tendon repair failed in two patients and they were reoperated with an allograft. Three patients developed infection and one of them required débridement. One developed deep venous thrombosis and two permanent sural nerve injuries were encountered. One of the patients had a severe skin necrosis, which was treated with rotation flap. The mean Rupp score was 29 (3-33).

CONCLUSION

Primary repair of acute tendo Achilles rupture augment with gastrosoleus turn down flip technique in combination of immediate weightbearing ambulation provides a good outcome, but is associated with similar complication rates to the previous literature.

Factors influencing the tensile strength of repaired Achilles tendon: a biomechanical experiment study

BACKGROUND

Operative treatment has been advocated as the method of choice to repair Achilles tendon rupture as surgery results in reduced re-rupture rate and faster rehabilitation. Many surgical techniques have been introduced allowing for postoperative early motion of the ankle joint. However, it is currently very difficult for surgeons to determine the optimal treatment conditions for ruptured Achilles tendon with an increasing number of end-to-end suture methods, suture materials, and epitenon suture techniques.

METHODS

In the present biomechanical experiment study based on an orthogonal design, thirty-two New Zealand white rabbits received Achilles tendon tenotomy and subsequent operative treatment to repair the tendon employing four end-to-end suture methods, four suture materials, and four epitenon suture techniques. The tensile strength of the repaired Achilles tendon was investigated at four rehabilitation periods, and in comparison with the results of another sixteen rabbits with normal Achilles tendons.

FINDINGS

The end-to-end suture method contributed most to the final Achilles tendon tensile strength in addition to rehabilitation period, with the highest values occurring with the use of the parachute-like ("Pa" bone) suture method. The other two factors, namely, suture material and epitenon suture technique, had relatively little influence on the results.

INTERPRETATION

The parachute-like ("Pa" bone) surgical technique is superior to the other three end-to-end suture methods, with enhanced tensile strength of the repaired tendon. This method allows for postoperative early kinesitherapy of the ankle and knee joints. Therefore, this technique is highly recommended in clinical situations for treatment of ruptured Achilles tendon.

Novel approach to repair of acute achilles tendon rupture: early recovery without postoperative fixation or orthosis

BACKGROUND

Immobilization or orthosis is required after conventional Achilles tendon surgery. Hypothesis This new Achilles tendon repair approach enables early rehabilitation without any postoperative immobilization or orthosis.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Twenty consecutive patients (14 men and 6 women; mean age, 43.4 years; range, 16-70 years) who had acute subcutaneous Achilles tendon rupture were treated by the new method, with an average follow-up of 2.9 years (range, 2-4.8 years). Among them, 15 injuries were sports-related and 5 were work-related. The authors applied a side-locking loop technique of their own design for the core suture, using braided polyblend suture thread, with peripheral cross-stitches added. The patients started active and passive ankle mobilization from the next day, partial weightbearing walking from 1 week, full-load walking from 4 weeks, and double-legged heel raises from 6 weeks after surgery.

RESULTS

The range of motion recovery equal to the intact side averaged 3.2 weeks. Double-legged heel raises and 20 continuous single-legged heel raise exercises were possible at an average of 6.3 weeks and 9.9 weeks, respectively. T2-weighted magnetic resonance signal intensity recovered to equal that of the intact portion of the same tendon at 12 weeks. The patients resumed sports activities or heavy labor at an average of 14.4 weeks. The Achilles tendon rupture score averaged 98.3 at 24 weeks. There were no complications.

CONCLUSION

This new Achilles tendon repair approach enables early mobilization exercise without costly specialized orthosis or immobilization and allows an early return to normal life and sports activities, reducing the physical and economic burden on patients.

Open repair of acute Achilles tendon ruptures

Although the Achilles tendon is the strongest in the body, it also is the most often ruptured. Achilles tendon rupture most often occurs during sports activities in middle-aged men. Operative repair of a ruptured Achilles tendon can be accomplished with a variety of techniques, ranging from open repair, to minimally invasive technique, to endoscopic-assisted repair. This article focuses on open repair of acute Achilles tendon rupture. Surgical techniques, rehabilitation protocol, and the authors' preferred method are described.

Percutaneous suturing of the ruptured Achilles tendon with endoscopic control

INTRODUCTION

A prospective study of modified percutaneous Achilles tendon repair performed between 1999 and 2005 under local infiltration anesthesia is presented; the study evaluated the results of percutaneous repair technique by visualization of the synovia under endoscopic control, followed by early functional postoperative treatment for surgical intervention of acute Achilles tendon ruptures.

PATIENTS

Sixty-two patients (58 males, 4 females, mean age 32) were treated by percutaneous suturing with modified Bunnel technique under endoscopic control within 10 days after acute total rupture. Physiotherapy was initiated immediately after the operation and patients were encouraged to weight-bearing ambulation with a walking brace-moon boot as tolerated. Full weight-bearing was allowed minimum after 3 weeks postoperatively without brace.

RESULTS

The procedure was tolerated in all patients. There were no significant ROM limitation was observed. Two patients experienced transient hypoesthesia in the region of sural nerve that spontaneously resolved in 6 months. Fifty-nine patients (95%) including professional athletes returned to their previous sportive activities, while 18 of them (29%) had some minor complaints. The interval from injury to return to regular work and rehabilitation training was 11.7 weeks (10-13 weeks). At the latest follow-up (mean: 46 months; range: 12-78 months), all the patients had satisfactory results with a mean American Orthopedic Foot and Ankle Society's ankle-hindfoot score of 94.6. No re-ruptures, deep venous thrombosis or wound problems occurred.

CONCLUSION

The proposed method offers a reasonable treatment option for acute total Achilles tendon rupture with a low number of complications. The rerupture rate and return to preinjury activities are comparable to open and percutaneous without endoscopic control procedures.

Force in the achilles tendon during walking with ankle foot orthosis

BACKGROUND

Ankle foot orthoses are used for postoperative treatment of Achilles tendon ruptures and decrease calf muscle electromyography activity during walking.

HYPOTHESIS

Achilles tendon load decreases with increased restriction of dorsiflexion and is associated with decreased triceps surae activity.

STUDY DESIGN

Controlled laboratory study.

METHODS

In 8 subjects, the maximum force and rate of force development in the Achilles tendon were measured with an optic fiber technique, and the activity of the gastrocnemius, soleus, and tibialis anterior muscles was recorded using electromyography. Trial conditions were walking barefoot and wearing an ankle-foot orthoses set in 3 different positions: (1) locked at 20 degrees of plantar flexion and with free plantar flexion but restricted dorsiflexion to (2) 10 degrees plantar flexion and (3) 10 degrees dorsiflexion, respectively. The design of the ankle foot orthoses did not provide heel support when fixed in a plantarflexed position.

RESULTS

Maximum Achilles tendon force was highest at the ankle-foot orthoses setting of 20 degrees plantar flexion (3.1 times body weight) and decreased to 2.1 times body weight during barefoot walking (P < .01). The rate of Achilles tendon force showed an increasing trend with less-restricted dorsiflexion. Soleus activity was 52% of mean barefoot walking activity at 3 20 degrees plantar flexion (P < .001) and then increased as dorsiflexion was less restricted.

CONCLUSION

Weightbearing in ankle-foot orthoses when dorsiflexion is restricted beyond neutral may result in increased forces in the Achilles tendon compared with barefoot walking, despite reduced electromyography activity in the triceps surae and decreased rate of force development.

CLINICAL RELEVANCE

If patients bear full weight in an ankle-foot orthoses locked at 20 degrees plantar flexion without heel support, the maximum force in the tendon may exceed that encountered during barefoot walking.

Augmented compared with nonaugmented surgical repair of a fresh total Achilles tendon rupture. A prospective randomized study

BACKGROUND

Augmented and nonaugmented techniques have been used for the operative repair of a fresh complete Achilles tendon rupture. Augmented techniques have been favored for their stronger pullout strengths but have been avoided because of the risk of wound complications. If proven to be equally good, the nonaugmented technique would be the method of choice. In the present study, we hypothesized that augmentation with a down-turned gastrocnemius fascia flap would not provide better results than would end-to-end suture repair with use of the Krackow locking loop surgical technique.

METHODS

Sixty patients with an acute Achilles tendon rupture were randomized preoperatively to receive end-to-end suture repair with use of the Krackow locking loop technique either without augmentation (simple repair group) or with a down-turned gastrocnemius fascia flap as described by Silfverskiöld (augmented repair group). A brace allowed free active plantar flexion of the ankle postoperatively, whereas dorsiflexion was restricted to neutral for the first three weeks. Weight-bearing was limited for six weeks. The follow-up period was one year, and the patients were evaluated in terms of clinical measurements, an outcome score, isokinetic calf muscle performance tests, and tendon elongation measurements.

RESULTS

The mean operative time was twenty-five minutes longer and the incision was 7 cm longer in the augmented repair group as compared with the simple repair group (p < 0.001 for both). In the simple repair group, the overall ankle score was excellent for nineteen patients (63%) and good for eight patients (27%) and three patients (10%) had an early failure (all because of rerupture). In the augmented repair group, the ankle score was excellent for fourteen patients (56%) and good for six patients (24%) and five patients (20%) had a failure because of rerupture (three) or deep infection (two). The difference between the groups with regard to the overall result was not significant (p = 0.68). In the simple repair group the isokinetic calf muscle strength score was excellent for eleven patients (37%), good for fourteen patients (47%), and fair for two patients (7%), with three patients (10%) having a failure, whereas in the augmented repair group the score was excellent for nine patients (36%), good for seven patients (28%), fair for three patients (12%), and poor for one patient (4%), with five patients (20%) having an early failure. Achilles tendon elongation occurred in both groups, and elongation correlated significantly with isokinetic peak torque deficits (rho = 0.64, p = 0.001) and isometric strength deficits (rho = 0.48, p = 0.026) in the simple repair group. No significant differences were seen between the two groups at the three-month and twelve-month checkups with regard to pain, stiffness, subjective calf muscle weakness, footwear restrictions, range of ankle motion, overall outcome, isokinetic calf muscle strength, mean peak work-displacement relationships, or tendon elongation.

CONCLUSIONS

Augmented repair of a fresh total Achilles tendon rupture does not have any advantage over simple end-to-end repair.

A new technique for small and secure knots using slippery polyethylene sutures

BACKGROUND

Suture knots used in tendon surgery must be strong but small enough so that they do not hinder gliding. For this purpose, we devised a unique "antislip" knot.

METHODS

Three suture materials were used: Ethibond, Fiberwire, and Nespron. They were tied with either the antislip knot using a pair of United States Pharmacopeia (USP) 2 sutures or with a conventional reef knot using USP2 single sutures. The volume and tensile strength of the knots were measured (n = 25 for each combination of suture and method).

FINDINGS

The maximum tensile strength was observed with Fiberwire antislip knots with five throws (mean 587 N) and six throws (mean 590 N), and Nespron antislip knots with five throws (mean 554 N) and six throws (mean 552 N); no significant differences were found among the four knots. Tensile strength per volume showed maximum values with Fiberwire antislip knots with four throws (mean 17.4 N/microl) and five throws (mean 16.8 N/microl), and Nespron antislip knots with four throws (mean 17.6 N/microl) and five throws (mean 16.8N/microl), which were not significantly different and were over 1.25-fold greater than the value for a reef knot. Ethibond had less tensile strength than Fiberwire and Nespron.

INTERPRETATION

The antislip knot is smaller for the same or greater strength than a conventional reef knot. The 4- or 5-throw antislip knot was most effective for slippery polyethylene sutures such as Fiberwire and Nespron. The antislip knot should improve biological healing of repaired tendons through accelerated rehabilitation.

Cyclic loading of 3 Achilles tendon repairs simulating early postoperative forces

BACKGROUND

The abstract goes here and covers two columns. Accelerated rehabilitation has been advocated after Achilles tendon repair, but it produces significant forces at the repair site. The abstract goes here and covers two columns.

HYPOTHESIS

Stresses applied to the repaired Achilles tendon simulating postoperative forces may exceed the strength of some repairs.

STUDY DESIGN

Controlled laboratory study.

METHODS

Fifteen Achilles tendons were incised 4 cm proximal to the calcaneal insertion, then were repaired using either a percutaneous, 4-strand Krackow, or an epitendinous augmented 4-strand Krackow technique. Tendons were cyclically loaded to 1000 cycles each at 100, 190, and 369 N. The number of cycles to initial gapping, 5-mm gapping, and total failure were compared using Mann-Whitney U tests with adjustments for multiple comparisons.

RESULTS

Gap resistance was significantly greater for augmented Krackow repairs (2208 cycles to initial gapping) versus nonaugmented repairs (502 cycles, P = .024) and for nonaugmented Krackow repairs versus percutaneous repairs (5 cycles, P = .024). All percutaneous repairs failed during the 100-N cycling (102 +/- 135 cycles). All nonaugmented Krackow repairs failed during the 190-N cycles (total cycles to failure: 1268 +/- 345). All augmented Krackow repairs were intact (no gapping) after the 190-N cycles. Four failed during 369-N cycling (total cycles to failure, 2017 +/- 11), and 1 remained intact for 3000 cycles.

CONCLUSION

Epitendinous cross-stitch weave augmentation of Achilles tendon repairs significantly increased repair strength and gap resistance.

CLINICAL RELEVANCE

Epitendinous cross-stitch weave augmentation of Achilles tendon repairs may better allow for early stretching and ambulation after Achilles tendon repair.

Optimizing Achilles tendon repair: effect of epitendinous suture augmentation on the strength of achilles tendon repairs

BACKGROUND

Epitendinous suture augmentation has been shown to increase gap resistance and overall strength in flexor tendon repairs of the hand. The purpose of this study was to evaluate the effect of various suture augmentation techniques in Achilles tendon repair.

MATERIALS AND METHODS

Eighteen fresh-frozen cadaveric Achilles tendons were transected and repaired with a 4-strand Krackow core stitch. Suture augmentation was performed with 3 figure-of-eight stitches in 6 specimens and a running cross-stitch weave in 6 specimens. The other 6 specimens were not augmented. Each tendon was loaded to failure on an MTS. Force to failure (defined as peak force or force at 5 mm gapping), gapping resistance, stiffness, and elongation were compared.

RESULTS

Force to failure (p < 0.001), stiffness (p < 0.01) and gapping resistance (p < 0.05) were increased by suture augmentation. Additionally failure force and gapping resistance for the cross-stitch augmentation was higher than the figure-of-eight augmentation (p < 0.05).

CONCLUSION

Cross-stitch augmentation of Achilles tendon repair yields a stronger and stiffer repair with greater resistance to gapping.

CLINICAL RELEVANCE

Achilles tendon repairs augmented with a cross stitch weave will be able to withstand substantially higher forces than non-augmented repairs.

Enveloping bioabsorbable polyglycolide membrane and immobilization in Achilles tendon repair: A comparative experimental study on rabbits

Using qualitative and histoquantitative methods, we investigated the effect of immobilization versus nonimmobilization on the biodegradation process, implant-tissue interaction, and scar formation after enveloping a rejoined rabbit Achilles tendon with a self-reinforced polyglycolide (SR-PGA) membrane. The soleus and gastrocnemius tendons of the right hind legs of 40 rabbits were transected. After suturing the ends, the seam was enveloped with the bioabsorbable membrane. Twenty ankles were immobilized with cast, 20 remained nonimmobilized. All nonoperated left ankles served as intact controls. During the follow-up of 3, 6, 12, and 24 weeks, scar formation, tissue response, and membrane biodegradation were studied histologically and histomorphometrically. The amount of scar tissue, highest at 3 weeks, gradually approached intact controls. SR-PGA degradation in both cast and noncast specimens was near complete by 24 weeks. Signs of an inflammatory process were most prominent at 3 weeks and diminished gradually by 24 weeks. No significant difference between cast and noncast specimens was noted at any time point regarding the amount of scar tissue, degradation process of PGA, or intensity of inflammatory reaction. In the present experimental setting, cast immobilization influenced neither scar formation nor speed of degradation during reunion of transected Achilles tendon ends as compared with nonimmobilization. No differences in the reunion process of the tendon ends were seen between the immobilized and nonimmobilized groups. Moreover, inflammatory cells were similar in both groups and reflected a transient tissue reaction to the membrane. Within the follow-up, the seam area (cross-sectional) approached that of intact controls.

A preliminary study on the effects of acellular tissue graft augmentation in acute Achilles tendon ruptures

Acute Achilles tendon rupture injuries present surgical challenges because of the mechanical forces placed on this tendon. The purpose of this study was to evaluate the effectiveness of an acellular human dermal tissue matrix, GraftJacket Matrix (Wright Medical Technology, Inc., Arlington, TN), as an augmentation material in acute Achilles tendon repair. Eleven consecutive patients with acute tendon ruptures were evaluated and followed up (20-31 months). Primary repair was followed by augmentation with the graft sutured circumferentially around the tendon. Patients were placed in an early functional rehabilitation program with postoperative evaluation at 3, 6, and 12 months. Outcome scores were calculated based on the American Orthopaedic Foot and Ankle Society ankle-hindfoot scoring system. At 20-month postoperative follow-up, there have been no cases of rerupture or recurrent pain. The average return-to-activity time was 11.8 +/- 0.75 weeks. These retrospective clinical results suggest that with an acellular human dermal tissue matrix to augment acute Achilles tendon, primary repair offers a desirable return-to-activity time without any rerupture or complications. ACFAS Level of Clinical Evidence: 2c.

A modified operation for Achilles tendon ruptures

BACKGROUND

Treatment of Achilles tendon rupture has long been at the center of debate.

HYPOTHESIS

A new technique in surgical Achilles tendon repair allows for more stability and earlier rehabilitation.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

One hundred Achilles tendon rupture patients (70 men, 30 women; age range, 16-54 years; mean age, 32 years) were treated by a newly modified method of repair. Twenty-one of these patients were high-level athletes, and 79 were recreational-level athletes. The average length of follow-up was 2.4 years (range, 1-6.3 years), and none of the ruptures included avulsion fractures. After adjusting the tendon to an adequate length using a Tsuge suture, each fibrous bundle was gathered in a longitudinal direction and fixed with a Bunnell-type suture. The same postoperative physical therapy protocol was applied to all patients: at 1 week, early full weightbearing with a walking cast was initiated, and at 2 weeks, patients began range of motion (ROM) exercises and were instructed to wear a hinged ankle-foot orthosis that permitted full plantar flexion but limited full dorsiflexion. From 6 weeks, patients started practicing double-legged heel raises.

RESULTS

At an average of 10 weeks, ankle ROM was comparable to that of the nonoperated leg, and double-legged heel raises were achieved at an average of 7.6 weeks. On average, patients were able to do 20 continuous single-legged heel-raising motions (equivalent to manual muscle testing grade 5) at 15.4 weeks, and jogging started at 12.3 weeks. High-level athletes returned to their original sports level at an average of 5 months. Two reruptures (2%) were experienced, but no other complications occurred.

CONCLUSION

This surgical technique allows for strong repair stability and subsequent early weightbearing and ROM exercises.

Biomechanical testing of epitenon suture strength in Achilles tendon repairs

BACKGROUND

Recent evidence that early, active mobilization protocols after Achilles tendon repairs increase recovery speed and strength make operative repair strength critical to positive outcomes after Achilles tendon ruptures. While previous research has focused on core (tendon proper) repair techniques, no previous literature has reported testing of core repairs augmented with epitenon sutures, which have been shown to increase the strength of repairs of flexor tendons of the hand.

METHODS

Five matched pairs of fresh frozen human Achilles tendons were tested with and without the addition of an epitenon suture to the core repair suture. All specimens were repaired using a No. 2 Ethibond Krakow locking loop core suture. The epitenon suture was added to one tendon randomly chosen from each pair, using a 4-0 nylon suture. All specimens were mounted on an MTS testing machine (MTS Systems Corp., Eden Prairie, MN) and loaded to failure, which was defined as a 1-cm gap formation.

RESULTS

The addition of epitenon sutures significantly increased the force necessary to produce a 2-mm gap as compared to core sutures alone by 74%, and it increased the average load to failure by 119%. Also, initial tendon stiffness was 173% greater in tendons reinforced with epitenon sutures.

CONCLUSIONS

This study demonstrates that greater resistance to gap formation, approximation of tissue ends, and tensile strength were achieved by the addition of an epitenon suture. Clinical relevance may improve healing by decreased gap formation at the repair site and a lower risk of adhesion formation.

SURGICAL REPAIR FOLLOWED BY FUNCTIONAL REHABILITATION FOR ACUTE AND CHRONIC ACHILLES TENDON INJURIES: EXCELLENT FUNCTIONAL RESULTS, PATIENT SATISFACTION AND NO RERUPTURES

BACKGROUND

We evaluated 46 patients who underwent surgical repair of the Achilles tendon at our institution during a 4.5-year period, followed by early weight bearing, aiming to assess their return to activities, rerupture rate and satisfaction.

METHODS

A cohort of 46 patients who underwent Achilles tendon repair at our institution during a 4.5-year period, with a modified triple mini-Becker suture technique, for both acute as well as chronic Achilles tendon ruptures were studied. These patients were reviewed at a minimum of 2.5 years follow up (average 4.5 years ranging from 2.5 to 6.5 years), by chart review and questionnaire, to determine the functional outcome as well as patient satisfaction following an active postoperative protocol involving full weight-bearing ambulation in a controlled ankle motion walker and active stretching, followed by a graduated strengthening programme.

RESULTS

We found a very high level of satisfaction, with few minor complications and no reruptures in either the early or the delayed repair groups.

CONCLUSION

We believe that surgical repair using this technique associated with an early return to protected full weight-bearing ambulation and an active early rehabilitation programme provides not only excellent functional results, patient satisfaction and a zero rerupture rate, but also much less morbidity in the first 3 months and a quicker overall recovery compared with non-operative treatment.

Cyclic loading of Achilles tendon repairs: a comparison of polyester and polyblend suture

BACKGROUND

Early functional rehabilitation is widely used after open suture repair of the Achilles tendon. To our knowledge, no previous studies have assessed gap formation from cyclic loading and subsequent failure loads of simulated Achilles tendon repairs. A synthetic (polyblend) suture has been introduced for tendon repairs with reportedly greater strength than polyester suture. This stronger, stiffer suture material may provide stronger repairs with less elongation of the tendon repair.

METHODS

Simulated Achilles tendon ruptures in bovine Achilles tendon were repaired with a four-strand Krackow suture technique using No. 2 polyester suture. Specimens were loaded for 3,000 cycles at maximal loads of 50, 75, 100, or 125 N, and gap formation at the repair site was continuously measured. After cyclic loading, each specimen was loaded to failure. Identical repairs were performed with number 2 polyblend suture and cyclically loaded to 75 N for 3,000 cycles. All specimens were loaded to failure.

RESULTS

Cyclically loading polyester suture repairs to 50, 75, 100, or 125 N for 3,000 cycles resulted in mean gapping at the repair site of 3.0 +/- 0.8, 4.9 +/- 1.0, 7.2 +/- 0.9, and 7.9 +/- 0.8 mm, respectively. Cyclically loading the polyblend suture repairs for 3,000 cycles at 75 N, resulted in 3.3 +/- 0.3 mm of gap formation at the repair site, significantly less than polyester suture repairs (p < 0.001). The mean load to failure for polyester suture repair was 222 +/- 19 N and for polyblend suture repair was 582 +/- 49 N, a statistically significant difference (p < 0.001). Gap formation at 100, 1,000, and 2,000 cycles, as a percentage of total gap formation at 3,000 cycles, was 64.3%, 87.5%, and 95.4% for polyester suture and 45.8%, 78.5%, and 90.1% for polyblend repairs. All specimens in all groups failed at the knots during load-to-failure testing.

CONCLUSIONS

Cyclic loading of simulated Achilles tendon repairs using a Krackow, four-core polyester suture technique showed progressive gap formation with increasing load. All repairs failed at the knot, and suture pull-out from tendon was not observed. Polyblend suture repair, when compared to identical repairs with braided polyester suture, resulted in a 260% higher load to failure and 33% less gap formation at the repair site after 3,000 cycles.

CLINICAL RELEVANCE

The use of polyblend suture in a four-stranded Krackow configuration provides stronger repairs with less gap formation, which may provide increased security during early functional rehabilitation.

Weakness in end-range plantar flexion after Achilles tendon repair

BACKGROUND

Separation of tendon ends after Achilles tendon repair may affect the tendon repair process and lead to postoperative end-range plantarflexion weakness.

HYPOTHESIS

Patients will have disproportionate end-range plantarflexion weakness after Achilles tendon repair.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Four-strand core suture repairs of Achilles tendon were performed on 1 female and 19 male patients. Postoperatively, patients were nonweightbearing with the ankle immobilized for 4 weeks. Plantarflexion torque, dorsiflexion range of motion, passive joint stiffness, toe walking, and standing single-legged heel rise (on an incline, decline, and level surface) were assessed after surgery (mean, 1.8 years postoperative; range, 6 months-9 years). Maximum isometric plantarflexion torque was measured at 20 degrees and 10 degrees of dorsiflexion, neutral, and 10 degrees and 20 degrees of plantar flexion. Percentage strength deficit (relative to noninvolved leg) was computed at each angle. Passive dorsiflexion range of motion was measured goniometrically. Passive joint stiffness was computed from increase in passive torque between 10 degrees and 20 degrees of dorsiflexion, before isometric contractions.

RESULTS

Significant plantarflexion weakness was evident on the involved side at 20 degrees and 10 degrees of plantar flexion (34% and 20% deficits, respectively; P <.001), with no torque deficits evident at other angles (6% at neutral, 3% at 10 degrees of dorsiflexion, 0% at 20 degrees of dorsiflexion). Dorsiflexion range of motion was not different between involved and noninvolved sides (P = .7). Passive joint stiffness was 34% lower on the involved side (P <.01). All patients could perform an incline heel rise; 14 patients could not perform a decline heel rise (P <.01).

CONCLUSION

Disproportionate weakness in end-range plantar flexion, decreased passive stiffness in dorsiflexion, and inability to perform a decline heel rise are evident after Achilles tendon repair. Possible causes include anatomical lengthening, increased tendon compliance, and insufficient rehabilitation after Achilles tendon repair.

CLINICAL RELEVANCE

Impairments will have functional implications for activities (eg, descending stairs and landing from a jump). Weakness in end-range plantar flexion may be an unrecognized problem after Achilles tendon repair.

Achilles tendon rupture: effect of early mobilization in rehabilitation after surgical repair

BACKGROUND

Surgical and nonsurgical treatments of Achilles tendon ruptures are available. Nonsurgical treatment using immobilization does not have the varying degrees of infection as seen with surgical procedures, but it frequently is linked to muscle atrophy, weakness, and higher rates of rerupture than surgical treatment. This study reports the results of 64 patients with Achilles tendon ruptures treated surgically and with early mobilization.

METHODS

Surgery of the ruptured tendon involved dividing the proximal stump into two separate strands and the distal stump into a single strand. The repair was advanced to a V-Y formation, and nonabsorbable sutures were used for repair. After wound closure, an early mobilization rehabilitation program was initiated, which consisted of wearing a moveable ankle brace for 4 to 6 weeks in 0 to 15 degrees of dorsiflexion and 10 weeks of regular exercises.

RESULTS

All 64 patients resumed normal activities in an average of 3.3 months regardless of whether the rupture was acute or chronic. Tendons healed with no reruptures. There were 13 complications, all wound infections, which healed when treated with antibiotics. The infection rate dropped markedly when wounds were inspected and dressings changed 1 week postoperatively, instead of at 2 weeks.

CONCLUSION

Surgery combined with early mobilization reduces range of motion loss, increases blood supply, and reduces the degree of muscle atrophy that typically occurs after Achilles tendon rupture, thereby decreasing the time to resumption of normal activities. Applying tension to the tendon also improved strength of the calf muscles and improved ankle movement. The main concern with early mobilization is rerupture, but this was lessened by patients carefully following the weightbearing and early mobilization protocols. The results of this study strengthen the argument to employ early mobilization rehabilitation after surgical repair.

Suture holding capacity of the Achilles tendon during the healing period: an in vivo experimental study in rabbits

BACKGROUND

Early motion and weightbearing is known to promote the healing of Achilles tendon repair. It is important to be informed about the repair strength for a secure rehabilitation. There are reports about the initial repair strength of Achilles tendons; however, they are mainly in vitro studies that represent the time zero strength of the repair. Softening of the tendon observed during the biological process of the tendon healing, which may effect the suture holding capacity and in turn the repair strength of the tendon has not been evaluated before.

METHODS

In the current study, the suture holding capacity of rabbit Achilles tendon was observed at various times during the healing period.

RESULTS

The suture holding capacity of the tendon at the end of the first and third weeks after surgery was found to be similar within 30% of the control tendon. However, at the end of the fourth week it was doubled reaching 65% of the control tendon.

CONCLUSIONS

Intrinsic tendon insufficiency which causes a decrease in the suture holding capacity of the tendon may lead to pull-out of the suture material during the postoperative third week. This period is precarious for early motion and weightbearing since the suture holding capacity of the tendon doubled relative to the previous three weeks.

Ex Vivo Strength Comparison of Bioabsorbable Tendon Plates and Bioabsorbable Suture in a 3-Loop Pulley Pattern for Repair of Transected Flexor Tendons from Horse Cadavers

OBJECTIVE

To test the failure strength and energy of 2 bioabsorbable implants applied to transected deep digital flexor tendons (DDFT) from adult horses.

STUDY DESIGN

Ex vivo biomechanical experiment.

SAMPLE POPULATION

Twelve pairs of deep digital flexor tendons harvested from the forelimbs of fresh equine cadavers.

METHODS

Poly-L-lactic acid tendon plates were custom manufactured for application to the cylindrical surface of an adult equine deep digital flexor tendon. Twelve pairs of DDFTs were transected 2 cm distal to the insertion of the distal check ligament of the deep digital flexor tendon. One tendon of each pair was randomly selected for repair with a biodegradable plate or a 3-loop pulley method. Size 2 polydioxanone suture was used in both repairs. Repairs were tested in tension to failure, with peak force (PF) and total energy (TE) at repair failure recorded in Newtons (N) and Joules (J), respectively. A paired t-test was used for statistical evaluation with a significant level set at P< or = .05.

RESULTS

Mean+/-SD PF for failure of plated tendons (1507.08+/-184.34 N) was significantly greater than for sutured tendons (460.86+/-60.93 N). TE was also significantly greater for failure of plated tendons versus sutured tendons.

CONCLUSIONS

Plate fixation of transected cadaver DDFTs appear to have superior immediate failure strength than 3-loop pulley repairs.

CLINICAL RELEVANCE

Whereas in vivo testing is required, a bioabsorbable tendon plate may provide initial increased strength to support tendon healing and decrease external coaptation requirements.

Optimum locations of the locking loop and knot in tendon sutures based on the locking Kessler method

BACKGROUND

We investigated the factors that influence tensile strength and resistance to gap formation at the repair site of tendon suture (stiffness) by comparing (1) the location of the locking loops and (2) the location of the knot.

METHODS

Transected bovine tendons of the medial gastrocnemius (9-11 x 14-16 mm diameter) were sutured with a modified locking Kessler method with a USP (United States Pharmacopeial convention) 2 polyester multifilament suture (0.500-0.599 mm) and loaded to failure using an Instron 5565 tensiometer. The locking loops were located on either the upper surface facing the operator or on side portions of the tendon. The knot was positioned either close to or far from the tendon stump.

RESULTS

The locations of the locking loops did not influence the tensile strength; however, the stiffness of the side loop suture (5.70 +/- 0.09 N/mm) was significantly higher than that of the upper surface loop suture (5.17 +/- 0.10 N/mm). Regarding the knot location, the tensile strength with the knot far from the tendon stump (195.1 +/- 4.8 N) was significantly higher than that with the knot close to the tendon stump (169.0 +/- 3.6 N), although the stiffness was unchanged by differences in knot location.

CONCLUSIONS

These data suggested that a greater tensile strength with less of a gap is obtained by (1) forming locking loops in the side portion of the tendon, and (2) forming knots far from the tendon stump.

Acute rupture of the Achilles tendon

Achilles tendon ruptures are common, and their incidence is increasing. The evidence for best management is controversial, and, in selected patients, conservative management and early mobilization achieves excellent results. Surgery is associated with an increased risk of superficial skin breakdown; however, modern techniques of percutaneous repair that are performed under local anesthesia and followed by early functional rehabilitation are becoming increasingly common, and should be considered when managing such patients.

Tensile properties and biological response of poly(L-lactic acid) felt graft: an experimental trial for rotator-cuff reconstruction

Poly(L-lactic acid) felt (PLLA felt) was prepared for reconstruction of the rotator cuff in animal models. Small changes were found in the tensile strength of both the cultured PLLA felt and the PLLA felt implanted on the paravertebral muscle of rabbits up to 16 postoperative weeks. The stiffness of the felt implanted on the muscle from 6 to 16 weeks showed a statistically significant increase. When the infraspinatus tendons of beagle dog were reconstructed with the PLLA felt, the ultimate strength of PLLA felt increased threefold, and the stiffness increased fivefold by 16 postoperative weeks compared to that of the initial PLLA felt. They were statistically significant (p < 0.01). All the implanted specimens ruptured at the junction between the bone and the PLLA felt. Histological examination demonstrated infiltration of fibrous tissue into the interstices of the PLLA felt fibers. Connection between the infraspinatus tendon and the PLLA felt was tight with the formed scar tissue, but the connective tissue between the bone and PLLA felt fibers was sparse even at 16 and 32 postoperative weeks. A few deteriorated PLLA felt fibers were observed at 32 postoperative weeks. It was concluded that the degradation rate of PLLA felt was low and the tensile recovery of the PLLA felt graft in beagle dogs was excellent. Thus, PLLA felt might be a useful bioabsorbable material for rotator-cuff reconstruction.

Functional efficacy of tendon repair processes

Despite various attempts to repair and replace injured tendon, an understanding of the repair processes and a systematic approach to achieving functional efficacy remain elusive. In this review the epidemiology of tendon injury and repair is first examined. Using a traditional paradigm for repair assessment, the biology and biomechanics of normal tendon, natural healing, and repair are then explored. New treatment strategies such as functional tissue engineering are discussed, including a functional approach to treatment that involves the development of in vivo functional design parameters to judge the acceptability of a repair outcome. The paper concludes with future directions.

Traumatic Achilles Tendon Rupture in a Female College Basketball Player

Objective:

To present the case of a Division I female college basketball player with a complete Achilles tendon rupture.

Background:

A 19-year-old, female college basketball player ruptured her right Achilles tendon during preseason conditioning. She had no previous history of heel cord symptoms.

Treatment:

The athlete underwent open surgical repair of Achilles tendon. The athlete successfully progressed through a functional rehabilitation program focused on early mobilization and weight bearing. The rehabilitation program was continually modified to address deficiencies and to keep the athlete actively engaged. She was cleared for full, unrestricted activity 15 weeks and 3 days after surgery and returned to game participation in 16 weeks.

Conclusions:

This case provides evidence that early mobilization and weight bearing can be used while still protecting the repaired tendon.

Diagnosis and Management of the Painful Ankle/Foot. Part 2: Examination, Interpretation, and Management

Diagnosis, interpretation, and subsequent management of ankle/foot pathology can be challenging to clinicians. A sensitive and specific physical examination is the strategy of choice for diagnosing selected ankle/foot injuries and additional diagnostic procedures, at considerable cost, may not provide additional information for clinical diagnosis and management. Because of a distal location in the sclerotome and the reduced convergence of afferent signals from this region to the dorsal horn of the spinal cord, pain reference patterns are low and the localization of symptoms is trustworthy. Effective management of the painful ankle/foot is closely linked to a tissue-specific clinical examination. The examination of the ankle/foot should include passive and resistive tests that provide information regarding movement limitations and pain provocation. Special tests can augment the findings from the examination, suggesting compromises in the structural and functional integrity of the ankle/foot complex. The weight bearing function of the ankle/foot compounds the clinician's diagnostic picture, as limits and pain provocation are frequently produced only when the patient attempts to function in weight bearing. As a consequence, clinicians should consider this feature by implementing numerous weightbearing components in the diagnosis and management of ankle/foot afflictions. Limits in passive motion can be classified as either capsular or non-capsular patterns. Conversely, patients can present with ankle/foot pain that demonstrates no limitation of motion. Bursitis, tendopathy, compression neuropathy, and instability can produce ankle/foot pain that is challenging to diagnose, especially when they are the consequence of functional weight bearing. Numerous non-surgical measures can be implemented in treating the painful ankle/foot, reserving surgical interventions for those patients who are resistant to conservative care.

Strength analysis and comparison of the Teno Fix Tendon Repair System with the two-strand modified Kessler repair in the Achilles tendon

BACKGROUND

Various options exist for repair of Achilles tendon ruptures, yet a method that consistently provides sufficient gap resistance to allow early mobilization remains elusive. This study compares the mechanical performance of a modified Kessler repair with that of the Teno Fix Tendon Repair System (Ortheon Medical, LLC) in matched pairs of cadaver Achilles tendons.

METHODS

The two-strand modified Kessler repair was selected as the control construct on the basis of literature review and physician interviews which identified it among the many options as a popular method for repair of acutely ruptured Achilles tendons. Test specimens were harvested from matched pairs of cadaver ankles. The tendons were transected 3.5 cm proximal to the calcaneal insertion and repaired with either the two-strand modified Kessler suture construct or the Teno Fix Tendon Repair System. Assignment to the modified Kessler or Teno Fix group was done randomly for the first member of each pair. All test and control repairs were performed by the same author to reduce variability. Evaluation of the repairs consisted of tensile strength testing and measurement of the gap formation and peak stresses.

RESULTS

Gap and peak stress for the two-strand modified Kessler repair were 0.30 +/- 0.15 N/mm2 and 1.03 +/- 0.51 N/mm2, respectively. For the Teno Fix repairs the mean gap and peak stress values were 0.80 +/- 0.46 N/mm2 and 1.19 +/- 0.12 N/mm2, respectively. The mean gap formation stress was significantly higher in the Teno Fix repairs than in the control repairs (p < .0005). There was no significant difference in peak strength between the repairs (p < .10).

CONCLUSIONS

The Teno Fix repair was superior to the modified Kessler repair. In the Teno Fix repairs, the gap formation stress was 67% of the peak tensile stress. In comparison, in the modified Kessler repairs, the gap formation stress was 29% of the peak stress. This can be correlated to the elastic property of the modified Kessler suture and the initial tightening of the suture around the tendon fibers. The Teno Fix system is nonelastic and is fully tensioned during installation. This lends to a more gap resistant repair.

Early weightbearing and ankle mobilization after open repair of acute midsubstance tears of the achilles tendon

PURPOSE

To study the effects of early weightbearing and ankle mobilization after acute repair of ruptured Achilles tendon.

STUDY DESIGN

Comparative longitudinal study.

METHODS

Patients in group 1 were postoperatively immobilized with their ankle in gravity equinus, they were encouraged to bear weight on the operated limb as soon as possible to full weightbearing, and they received a single cast change at 2 weeks, with the ankle accommodated in an anterior splint in a plantigrade position, allowing the ankle to be plantar flexed fully but not dorsiflexed above neutral. Patients in group 2 were immobilized with their ankle in full equinus with a cast change at 2 weeks, when the ankle was immobilized in mid equinus, and at 4 weeks, when the ankle was immobilized in a plantigrade position, and they were advised to bear weight.

RESULTS

Patients in group 1 attended fewer outpatient visits, completely discarded their crutches at an average of 2.5 weeks, and more were satisfied with the results of surgery. At ultrasonography, the average thickness of the repaired tendon was 12.1 mm, with no difference in the thickness of the ruptured tendon regardless of postoperative management. There was no significant difference in isometric strength between the two groups.

CONCLUSIONS

Early weightbearing with the ankle plantigrade is not detrimental to the outcome of repair after acute rupture of the Achilles tendon and shortens the time needed for rehabilitation. However, strength deficit and muscle atrophy are not prevented.

Quantitative review of operative and nonoperative management of achilles tendon ruptures

BACKGROUND

There is no consensus on the best method for management of acute Achilles tendon ruptures. Individual preferences, drawn from experience and study, determine whether treatment is operative or nonoperative.

PURPOSE

Our goal was to review the literature to try to determine what management method was the most popular and effective. We wanted to ascertain the best results in terms of complication rates and patient outcomes.

STUDY DESIGN

Retrospective review of retrospectively and prospectively collected data.

METHODS

We analyzed 125 articles in peer-reviewed journals for year of publication, patient numbers, sex, management method, follow-up complications, and patient satisfaction. Each article was graded using a validated methods score. Methods, patient satisfaction, and complication rates were correlated with the year each article was published.

RESULTS

Skin-healing complications were lowest in conservatively managed patients (3 of 578, 0.5%) and highest in open repair and immobilized patients (543 of 3718, 14.6%). General complication rates were lowest in open repair and early-mobilization groups (16 of 238, 6.7%) and highest in percutaneous and early-mobilization groups (19 of 122, 15.6%). Rerupture rates were highest in immobilized conservative management groups (62 of 578, 10.7%) and lowest in groups with external fixation (0%).

CONCLUSIONS

In general, the number of publications reporting Achilles tendon ruptures is increasing, the quality of articles is increasing, and the trend for the number of reported complications is decreasing. The published articles had a low methods score (mean, 50.9; range, 25 to 77) and showed a trend toward earlier mobilization. Open repair and early mobilization give the best functional recovery and an acceptable complication rate.

Achilles tendon disorders in athletes

Achilles tendon disorders are among the more common maladies seen by sports medicine physicians. Understanding the anatomy and biomechanics of the Achilles tendon and contiguous structures is essential to the diagnosis and treatment of Achilles tendon overuse injuries. Posterior heel pain is multifactorial and includes paratenonitis, tendinosis, tendinosis with partial rupture, insertional tendinitis, retrocalcaneal bursitis, and subcutaneous tendo-Achilles bursitis. Each of these entities is distinct, but they often occur in combination. Although most cases of this disorder are successfully treated nonoperatively, a small subgroup of recalcitrant cases may benefit from surgical intervention. Complete ruptures in active, athletic persons should be treated operatively in most cases and result in predictably good outcomes. There may be some cases that escape early recognition and require a reconstructive procedure to salvage a potentially severe functional deficit.

The relative stress on the Achilles tendon during ambulation in an ankle immobiliser: implications for rehabilitation after Achilles tendon repair

BACKGROUND

After Achilles tendon repair, immediate weightbearing and immobilisation closer to neutral plantarflexion are thought to limit atrophy and stiffness, but may place deleterious stress on the repair.

OBJECTIVES

To estimate the relative stress on the Achilles tendon during weightbearing with immobilisation in varying degrees of plantarflexion.

METHODS

Electromyographic (EMG) activity from the plantarflexors was recorded during walking in 10 subjects (six men, four women) without ankle pathology. Four walking conditions were examined: (a) normal walking; (b) immobilised (cam-walker) in neutral plantarflexion; (c) immobilised with a 0.5 inch heel lift; (d) immobilised with a 1 inch heel lift. EMG activity relative to plantarflexor torque was determined for each subject during isometric contractions at 25%, 50%, 75%, and 100% of maximal voluntary contraction (MVC). EMG activity during walking was calculated as a percentage of MVC based on the EMG-torque relation during graded isometric contractions.

RESULTS

During normal walking, the plantarflexor torque was estimated to be 30 (12)% (mean (SD)) of MVC, compared with 21 (15)% MVC for immobilisation in neutral (p<0.05), 17 (15)% MVC with the addition of a 0.5 inch heel lift (p<0.01), and 12 (12)% MVC with the addition of a 1 inch heel lift (p<0.01). The 1 inch heel lift resulted in less than 10 degrees plantarflexion in all subjects.

CONCLUSIONS

When the ankle is immobilised, stress on the Achilles tendon is determined by the degree of plantarflexion and the contractile activity of the plantarflexors. In the immobilised ankle, the addition of a 1 inch heel lift was sufficient to minimise plantarflexor activity during walking.

Fibrous connection to bone after immediate repair of the canine infraspinatus: the most effective bony surface for tendon attachment

The purpose of this histologic study was to identify the most effective bony surface for fibrous connection to bone after immediate repair of the canine infraspinatus. Light microscopic views were used to evaluate collagen fiber development. The left infraspinatus tendon of 15 dogs was transected and repaired to 3 different bone surfaces: a tendon end adjacent to the tendon insertion (group 1, n = 5), a calcified fibrocartilage layer (group 2, n = 5), and a cancellous surface (group 3, n = 5). Tendon repair to distal tendon ends restored the 4-layered enthesis in the healing period, whereas tendon repair to the calcified fibrocartilage layer considerably delayed fiber development into bone. Fiber connection to cancellous surface developed according to the remodeling of trabecular bone. Secure fiber connection into the thickened trabecular bone developed by 16 postoperative weeks. On the basis of these results, in clinical settings, ruptured tendon ends should be attached to the remaining distal tendon end or to a cancellous surface; they should not be attached to a calcified fibrocartilage layer.